ba Federal Watchdog Backs Reinstating Ousted Vaccine Expert By feeds.drudge.com Published On :: Fri, 08 May 2020 20:23:47 -0400 A federal watchdog is recommending that ousted vaccine expert Rick Bright be reinstated while it investigates whether the Trump administration retaliated against his whistleblower complaints when it removed him from a key post overseeing the coronavirus response, Bright's lawyers said Friday. Full Article news
ba GOP Plans to Spend at least $20 million to Combat Voting Rights Lawsuits By feeds.drudge.com Published On :: Sat, 09 May 2020 12:32:21 -0400 The Republican National Committee and President Donald Trump's reelection campaign have doubled their litigation budget to $20 million, Politico reported Thursday. RNC chief of staff Richard Walters told Politico that the GOP is prepared to sue Democrats "into oblivion" by spending "whatever is necessary" to prevail in legal fights against its rivals leading up to the November election. Full Article news
ba Say Yes, Figure It Out Later. Starting from the Start with Tyler Babin By feedproxy.google.com Published On :: Wed, 03 Jul 2019 13:15:14 +0000 “It’s impossible to move forward while staying the same”. That’s what motivated Tyler Babin, a 25 year old up & coming filmmaker, who hustled his way into his dream job only to leave it to pursue the riskier thing, an even bigger bet – on himself. I’ve had literally hundreds of requests over the years to have someone on the show who isn’t Richard Branson or Brene Brown or {fill in the blank star}…ie. host someone who hasn’t “made it big” and is, instead, on the come-up themselves…someone from within our very own community who has been listening for years, connecting dots, gleaning knowledge and is now taking major action on that. Well THIS is Tyler’s story. If you’ve followed my pal Gary Vaynerchuk, it’s likely you’ve actually seen some of Tyler’s work. For the last 3-4 years, he’s been a whirlwind tour traveling the world with Gary, shooting photo + video, creative directing projects at Vayner… and it all started right here on this show nearly 8 years ago. This episode goes full circle, friends. Also – instead of the usual studio conversation, Tyler and I recorded the show while grabbing a burger & margarita just around the corner […] The post Say Yes, Figure It Out Later. Starting from the Start with Tyler Babin appeared first on Chase Jarvis Photography. Full Article chasejarvisLIVE Podcast adobe content creator creative residency Filmmaking Gary Vaynerchuk photography
ba Intuition, Creative Freedom & Doing What You Love with Chris Ballew By feedproxy.google.com Published On :: Wed, 14 Aug 2019 13:15:04 +0000 Today’s episode is going to rock your world … pun fully intended because today’s guest is an actual rock star. You may remember a band called Presidents of the United States of America. They took the world by storm in 1995 with their self titled album, Presidents of the United States of America playing songs like Lump and Peaches. Yes, that’s right. My guest today is frontman Chris Ballew. Chris and I have been friends for years, including collaborating on a music video together and at least one live performance (gotta listen to find out ;). Of course we get into his musical journey, a meteoric rise to success, and then realizing something was missing. We take some deep dives into Chris’ creative process, including his method for capturing his small bits and later using those to write new works, including his new project Casper Babypants. In this episode: Consider what kind of artist you are and how you relate to other artists. For years Chris played in bands, but what he learned about himself is his work is actually solo. Don’t censor yourself while you’re creating. Get it out, no matter how crazy or ridiculous or unusual and then […] The post Intuition, Creative Freedom & Doing What You Love with Chris Ballew appeared first on Chase Jarvis Photography. Full Article chasejarvisLIVE Podcast art Caspar Babypants chris ballew creative process Inspiration music
ba Harmony > Balance with Jason Calacanis By feedproxy.google.com Published On :: Wed, 06 Nov 2019 14:27:08 +0000 Today we’re going back to San Francisco with myself and Jason Calacanis on stage during my tour stop for my book Creative Calling. Jason is an investor and long time host of the This Week in Startups podcast. And, of course, Jason wastes no time in our conversation. He goes right to the heart of the matter by getting into failure, venture capitol, knowing when to quit, and when to push through. Enjoy! FOLLOW JASON: facebook | twitter | website Listen to the Podcast Subscribe This podcast is brought to you by CreativeLive. CreativeLive is the world’s largest hub for online creative education in photo/video, art/design, music/audio, craft/maker, money/life and the ability to make a living in any of those disciplines. They are high quality, highly curated classes taught by the world’s top experts — Pulitzer, Oscar, Grammy Award winners, New York Times best selling authors and the best entrepreneurs of our times. The post Harmony > Balance with Jason Calacanis appeared first on Chase Jarvis Photography. Full Article Business chasejarvisLIVE Podcast Book Tour Creative Calling creativity interview Jason Calacanis
ba 10 Breaths Back to Love with Kamal Ravikant By feedproxy.google.com Published On :: Wed, 26 Feb 2020 14:15:09 +0000 Kamal Ravikant was in a dark place. After four years of pouring his heart, soul, and money into his tech startup, it blew up. He lost everything – including himself. In a moment of desperation, a vow deep within came to the surface: to love himself. Though it was a bit of a foreign concept, he set out to undo the misery in his head through the lens of love. The practice Kamal formed became the self-published book: Love Yourself Like Your Life Depends on It. It sold over a half a million copies and is now newly expanded. In our conversation Kamal shares his ruthlessly practical way he unwound the negative thoughts and more importantly, made it last. In our conversation we explore: Mindset as a practice, including the 7 minute meditation Kamal uses to break old mental patterns Kamal shares his advice in getting unstuck, including giving yourself time to simply live Our brain is a monkey gone bananas. Pain, joy, loneliness, love are a universal part of the human condition such that no matter our individual circumstance we are all trying to tame it. and much more… Enjoy! FOLLOW KAMAL: instagram | twitter | website Listen to the Podcast […] The post 10 Breaths Back to Love with Kamal Ravikant appeared first on Chase Jarvis Photography. Full Article chasejarvisLIVE Podcast breath meditation mindset writer
ba Markdown Comes Alive! Part 1, Basic Editor By feedproxy.google.com Published On :: Wed, 26 Feb 2020 08:00:00 -0500 In my last post, I covered what LiveView is at a high level. In this series, we’re going to dive deeper and implement a LiveView powered Markdown editor called Frampton. This series assumes you have some familiarity with Phoenix and Elixir, including having them set up locally. Check out Elizabeth’s three-part series on getting started with Phoenix for a refresher. This series has a companion repository published on GitHub. Get started by cloning it down and switching to the starter branch. You can see the completed application on master. Our goal today is to make a Markdown editor, which allows a user to enter Markdown text on a page and see it rendered as HTML next to it in real-time. We’ll make use of LiveView for the interaction and the Earmark package for rendering Markdown. The starter branch provides some styles and installs LiveView. Rendering Markdown Let’s set aside the LiveView portion and start with our data structures and the functions that operate on them. To begin, a Post will have a body, which holds the rendered HTML string, and title. A string of markdown can be turned into HTML by calling Post.render(post, markdown). I think that just about covers it! First, let’s define our struct in lib/frampton/post.ex: defmodule Frampton.Post do defstruct body: "", title: "" def render(%__MODULE{} = post, markdown) do # Fill me in! end end Now the failing test (in test/frampton/post_test.exs): describe "render/2" do test "returns our post with the body set" do markdown = "# Hello world!" assert Post.render(%Post{}, markdown) == {:ok, %Post{body: "<h1>Hello World</h1> "}} end end Our render method will just be a wrapper around Earmark.as_html!/2 that puts the result into the body of the post. Add {:earmark, "~> 1.4.3"} to your deps in mix.exs, run mix deps.get and fill out render function: def render(%__MODULE{} = post, markdown) do html = Earmark.as_html!(markdown) {:ok, Map.put(post, :body, html)} end Our test should now pass, and we can render posts! [Note: we’re using the as_html! method, which prints error messages instead of passing them back to the user. A smarter version of this would handle any errors and show them to the user. I leave that as an exercise for the reader…] Time to play around with this in an IEx prompt (run iex -S mix in your terminal): iex(1)> alias Frampton.Post Frampton.Post iex(2)> post = %Post{} %Frampton.Post{body: "", title: ""} iex(3)> {:ok, updated_post} = Post.render(post, "# Hello world!") {:ok, %Frampton.Post{body: "<h1>Hello world!</h1> ", title: ""}} iex(4)> updated_post %Frampton.Post{body: "<h1>Hello world!</h1> ", title: ""} Great! That’s exactly what we’d expect. You can find the final code for this in the render_post branch. LiveView Editor Now for the fun part: Editing this live! First, we’ll need a route for the editor to live at: /editor sounds good to me. LiveViews can be rendered from a controller, or directly in the router. We don’t have any initial state, so let's go straight from a router. First, let's put up a minimal test. In test/frampton_web/live/editor_live_test.exs: defmodule FramptonWeb.EditorLiveTest do use FramptonWeb.ConnCase import Phoenix.LiveViewTest test "the editor renders" do conn = get(build_conn(), "/editor") assert html_response(conn, 200) =~ "data-test="editor"" end end This test doesn’t do much yet, but notice that it isn’t live view specific. Our first render is just the same as any other controller test we’d write. The page’s content is there right from the beginning, without the need to parse JavaScript or make API calls back to the server. Nice. To make that test pass, add a route to lib/frampton_web/router.ex. First, we import the LiveView code, then we render our Editor: import Phoenix.LiveView.Router # … Code skipped ... # Inside of `scope "/"`: live "/editor", EditorLive Now place a minimal EditorLive module, in lib/frampton_web/live/editor_live.ex: defmodule FramptonWeb.EditorLive do use Phoenix.LiveView def render(assigns) do ~L""" <div data-test=”editor”> <h1>Hello world!</h1> </div> """ end def mount(_params, _session, socket) do {:ok, socket} end end And we have a passing test suite! The ~L sigil designates that LiveView should track changes to the content inside. We could keep all of our markup in this render/1 method, but let’s break it out into its own template for demonstration purposes. Move the contents of render into lib/frampton_web/templates/editor/show.html.leex, and replace EditorLive.render/1 with this one liner: def render(assigns), do: FramptonWeb.EditorView.render("show.html", assigns). And finally, make an EditorView module in lib/frampton_web/views/editor_view.ex: defmodule FramptonWeb.EditorView do use FramptonWeb, :view import Phoenix.LiveView end Our test should now be passing, and we’ve got a nicely separated out template, view and “live” server. We can keep markup in the template, helper functions in the view, and reactive code on the server. Now let’s move forward to actually render some posts! Handling User Input We’ve got four tasks to accomplish before we are done: Take markdown input from the textarea Send that input to the LiveServer Turn that raw markdown into HTML Return the rendered HTML to the page. Event binding To start with, we need to annotate our textarea with an event binding. This tells the liveview.js framework to forward DOM events to the server, using our liveview channel. Open up lib/frampton_web/templates/editor/show.html.leex and annotate our textarea: <textarea phx-keyup="render_post"></textarea> This names the event (render_post) and sends it on each keyup. Let’s crack open our web inspector and look at the web socket traffic. Using Chrome, open the developer tools, navigate to the network tab and click WS. In development you’ll see two socket connections: one is Phoenix LiveReload, which polls your filesystem and reloads pages appropriately. The second one is our LiveView connection. If you let it sit for a while, you’ll see that it's emitting a “heartbeat” call. If your server is running, you’ll see that it responds with an “ok” message. This lets LiveView clients know when they've lost connection to the server and respond appropriately. Now, type some text and watch as it sends down each keystroke. However, you’ll also notice that the server responds with a “phx_error” message and wipes out our entered text. That's because our server doesn’t know how to handle the event yet and is throwing an error. Let's fix that next. Event handling We’ll catch the event in our EditorLive module. The LiveView behavior defines a handle_event/3 callback that we need to implement. Open up lib/frampton_web/live/editor_live.ex and key in a basic implementation that lets us catch events: def handle_event("render_post", params, socket) do IO.inspect(params) {:noreply, socket} end The first argument is the name we gave to our event in the template, the second is the data from that event, and finally the socket we’re currently talking through. Give it a try, typing in a few characters. Look at your running server and you should see a stream of events that look something like this: There’s our keystrokes! Next, let’s pull out that value and use it to render HTML. Rendering Markdown Lets adjust our handle_event to pattern match out the value of the textarea: def handle_event("render_post", %{"value" => raw}, socket) do Now that we’ve got the raw markdown string, turning it into HTML is easy thanks to the work we did earlier in our Post module. Fill out the body of the function like this: {:ok, post} = Post.render(%Post{}, raw) IO.inspect(post) If you type into the textarea you should see output that looks something like this: Perfect! Lastly, it’s time to send that rendered html back to the page. Returning HTML to the page In a LiveView template, we can identify bits of dynamic data that will change over time. When they change, LiveView will compare what has changed and send over a diff. In our case, the dynamic content is the post body. Open up show.html.leex again and modify it like so: <div class="rendered-output"> <%= @post.body %> </div> Refresh the page and see: Whoops! The @post variable will only be available after we put it into the socket’s assigns. Let’s initialize it with a blank post. Open editor_live.ex and modify our mount/3 function: def mount(_params, _session, socket) do post = %Post{} {:ok, assign(socket, post: post)} end In the future, we could retrieve this from some kind of storage, but for now, let's just create a new one each time the page refreshes. Finally, we need to update the Post struct with user input. Update our event handler like this: def handle_event("render_post", %{"value" => raw}, %{assigns: %{post: post}} = socket) do {:ok, post} = Post.render(post, raw) {:noreply, assign(socket, post: post) end Let's load up http://localhost:4000/editor and see it in action. Nope, that's not quite right! Phoenix won’t render this as HTML because it’s unsafe user input. We can get around this (very good and useful) security feature by wrapping our content in a raw/1 call. We don’t have a database and user processes are isolated from each other by Elixir. The worst thing a malicious user could do would be crash their own session, which doesn’t bother me one bit. Check the edit_posts branch for the final version. Conclusion That’s a good place to stop for today. We’ve accomplished a lot! We’ve got a dynamically rendering editor that takes user input, processes it and updates the page. And we haven’t written any JavaScript, which means we don’t have to maintain or update any JavaScript. Our server code is built on the rock-solid foundation of the BEAM virtual machine, giving us a great deal of confidence in its reliability and resilience. In the next post, we’ll tackle making a shared editor, allowing multiple users to edit the same post. This project will highlight Elixir’s concurrency capabilities and demonstrate how LiveView builds on them to enable some incredible user experiences. Full Article Code Back-end Engineering
ba A Parent’s Guide to Working From Home, During a Global Pandemic, Without Going Insane By feedproxy.google.com Published On :: Thu, 30 Apr 2020 15:06:00 -0400 Though I usually enjoy working from Viget’s lovely Boulder office, during quarantine I am now working from home while simultaneously parenting my 3-year-old daughter Audrey. My husband works in healthcare and though he is not on the front lines battling COVID-19, he is still an essential worker and as such leaves our home to work every day. Some working/parenting days are great! I somehow get my tasks accomplished, my kid is happy, and we spend some quality time together. And some days are awful. I have to ignore my daughter having a meltdown and try to focus on meetings, and I wish I wasn’t in this situation at all. Most days are somewhere in the middle; I’m just doing my best to get by. I’ve seen enough working parent memes and cries for help on social media to know that I’m not alone. There are many parents out there who now get to experience the stress and anxiety of living through a global pandemic while simultaneously navigating ways to stay productive while working from home and being an effective parent. Fun isn’t it? I’m not an expert on the matter, but I have found a few small things that are making me feel a bit more sane. I hope sharing them will make someone else’s life easier too. Truths to Accept First, let’s acknowledge some truths about this new situation we find ourselves in: Truth 1: We’ve lost something. Parents have lost more than daycare and schools during this epidemic. We’ve lost any time that we had for ourselves, and that was really valuable. We no longer have small moments in the day to catch up on our personal lives. I no longer have a commute to separate my work duties from my mom duties, or catch up with my friends, or just be quiet. Truth 2: We’re human. The reason you can’t be a great employee and a great parent and a great friend and a great partner or spouse all day every day isn’t because you’re doing a bad job, it’s because being constantly wonderful in all aspects of your life is impossible. Pick one or two of those things a day to focus on. Truth 3: We’re all doing our best. This is the most important part of this article. Be kind to yourselves. This isn’t easy, and putting so much pressure on yourself that you break isn’t going to make it any easier. Work from Home Goals Now that we’ve accepted some truths about our current situation, let’s set some goals. Goal 1: Do Good Work At Viget, and wherever you work, with kids or without we all want to make sure that the quality of our work stays up throughout the pandemic and that we can continue to be reliable team members and employees to the best of our abilities. Goal 2: Stay Sane We need to figure out ways to do this without sacrificing ourselves entirely. For me, this means fitting my work into normal work hours as much as possible so that I can still have some downtime in the evenings. Goal 3: Make This Sustainable None of us knows how long this will last but we may as well begin mentally preparing for a long haul. Work from Home Rules Now, there are some great Work from Home Rules that apply to everyone with or without kids. My coworker Paul Koch shared these with the Viget team a Jeremy Bearimy ago and I agree this is also the foundation for working from home with kids. When you’re in a remote meeting, minimize other windows to stay focusedSet a schedule and avoid chores*Take breaks away from the screenPlan your workday on the calendar+Be mindful of Slack and social media as a distractionUse timers+Keep your work area separate from where you relaxPretend that you’re still WFWExperiment and figure out what works for you In the improv spirit I say “Yes, AND….” to these tips. And so, here are my adjusted rules for WFH while kiddos around: These have both been really solid tools for me, so let’s dig in. Daily flexible schedule for kids Day Planning: Calendars and Timers A few small tweaks and adjustments make this even more doable for me and my 3-year-old. First- I don’t avoid chores entirely. If I’m going up and down the stairs all day anyway I might as well throw in a load of laundry while I’m at it. The more I can get done during the day means a greater chance of some down time in the evening. Each morning I plan my day and Audrey’s day: My Work Day:Audrey's DayIdentify times of day you are more likely to be focus and protect them. For me, I know I have a block of time from 5-7a before Audrey wakes up and again during “nap time” from 1-3p.I built a construction paper “schedule” that we update and reorganize daily. We make the schedule together each day. She feels ownership over it and she gets to be the one who tells me what we do next.Look at your calendar first thing and make adjustments either in your plans or move meetings if you have to.I’m strategic about screen time- I try to schedule it when I have meetings. It also helps to schedule a physical activity before screen time as she is less likely to get bored.Make goals for your day: Tackle time sensitive tasks first. Take care of things that either your co-workers or clients are waiting on from you first, this will help your day be a lot less stressful. Non-time sensitive tasks come next- these can be done at any time of day.We always include “nap time” even though she rarely naps anymore. This is mostly a time for us both to be alone. When we make the schedule together it also helps me understand her favorite parts of the day and reminds me to include them. Once our days are planned, I also use timers to help keep the structure of the day. (I bought a great alarm clock for kids on Amazon that turns colors to signal bedtime and quiet time. It’s been hugely worth it for me.) Timers for Me:Timers for Audrey:More than ever, I rely on a time tracking timer. At Viget we use Harvest to track time, and it has a handy built in timer, but there are many apps or online tools that could help you keep track of your time as well.Audrey knows what time she can come out of her room in the morning. If she wakes up before the light is green she plays quietly in her room.I need a timer because the days and hours are bleeding together- without tracking as I go it would be really hard for me to remember when I worked on certain projects or know for certain if I gave Viget enough time for the day.She knows how long “nap time” is in the afternoon.Starting and stopping the timer helps me turn on and off “work mode”, which is a helpful sanity bonus.Perhaps best of all I am not the bad guy! “Sorry honey, the light isn’t green yet and there really isn’t anything mommy can do about it” is my new favorite way to ensure we both get some quiet time. Work from Home Rules: Updated for Parents Finally, I have a few more Work from Home Rules for parents to add to the list: Minimize other windows in remote meetingsSet a schedule and fit in some chores if time allowsTake breaks away from the screenSchedule both your and your kids’ daysBe mindful of Slack and social media as a distractionUse timers to track your own time and help your kids understand the dayKeep your work area separate from where you relaxPretend that you’re still WFWExperiment and figure out what works for youBe prepared with a few activitiesEach morning, have just ONE thing ready to go. This can be a worksheet you printed out, a coloring station setup, a new bag of kinetic sand you just got delivered from Amazon, a kids dance video on YouTube or an iPad game. Recently I started enlisting my mom to read stories on Facetime. The activity doesn’t have to be new each day but (especially for young kids) it has to be handy for you to start up quickly if your schedule changesClearly communicate your availability with your team and project PMsLife happens. Some days are going to be hard. Whatever you do, don’t burn yourself out or leave your team hanging. If you need to move a meeting or take a day off, communicate that as early and as clearly as you can.Take PTO if you canNone of us are superheroes. If you’re feeling overwhelmed- take a look at the next few days and figure out which one makes the most sense for you to take a break.Take breaks to be alone without doing a taskWork and family responsibilities have blended together, there’s almost no room for being alone. If you can find some precious alone time don’t use it to fold laundry or clean the bathroom. Just zone out. I think we all really need this. Last but not least, enjoy your time at home if you can. This is an unusual circumstance and even though it’s really hard, there are parts that are really great too. If you have some great WFH tips we’d love to hear about them in the comments! Full Article Process News & Culture
ba So You've Written a Bad Design Take By feedproxy.google.com Published On :: Tue, 05 May 2020 08:00:00 -0400 So you’ve just written a blog post or tweet about why wireframes are becoming obsolete, the dangers of “too accessible” design, or how a certain style of icon creates “cognitive fatigue.” Your post went viral, but now you’re getting ratioed by rude people on the Internet. That sucks! You were just trying to start a conversation and you probably didn’t deserve all that negativity (except for you, “too accessible” guy). Most likely, you made one of these common mistakes: 1. You made generalizations about “design” You, a good user-centered designer, know that you are not your user. Nor are you every designer. First of all, let's acknowledge that there is no universal definition of design. Even if we narrow it down to software design, it’s still hard to make generalizations. Agency, in-house, product, startup, enterprise, non-profit, website, app, connected hardware, etc. – there are a lot of different work contexts and cultures for people with “designer” in their titles. "The Design Industry" is not a thing, but even if it were, you don't speak for it. Don’t assume that the kind of design work you do is the universal default. 2. You didn’t share enough context There are many great design books and few great design blog posts. (There are, to my knowledge, no great design tweets, but I am open to your suggestions.) Writing about design is not well suited to short formats, because context plays such an important role and there’s always a lot of it to cover. Writing about your work should include as much context as you would include if you were presenting your portfolio for a job interview. What kind of organization did you work for? Who was your client and/or your stakeholders? What was the goal of the project? Your timeline? What was the makeup of your team? What were the notable business rules and constraints? How are you defining effectiveness and success? Without these kinds of details, it’s not possible for other designers to know if what you’ve written is credible or applicable to them. 3. You were too certain A blog post doesn’t need to be a dissertation. It’s okay to share hunches and anecdotes, but give the necessary caveats. And if you're making claims about science, bruh, you gotta cite your sources. Be humble in your takes. Your account of what worked for you and why is more valuable to your peers than making sweeping claims and reheating the same old arguments. Be prepared to be told you’re wrong, and have the humility to realize that your perspective is just your perspective. Real conversations, like good design, are built on feedback and diverse viewpoints. — Together, we can improve the discourse in our information ecosystems. Don't generalize. Give context. Be humble. Full Article Design & Content User Experience
ba Should you use Userbase for your next static site? By feedproxy.google.com Published On :: Wed, 06 May 2020 08:00:00 -0400 During the winter 2020 Pointless Weekend, we built TrailBuddy (working app coming soon). Our team consisted of four developers, two project managers, two front-end developers, a digital-analyst, a UXer, and a designer. In about 48 hours, we took an idea from Jeremy Field’s head to a (mostly) working app. We broke up the project in two parts:. First, a back-end that crunches trail, weather, and soil data. That data is exposed via a GraphQL API for a web app to consume. While developers built the API, I built a static front end using Next.js. Famously, static front-ends don’t have a database, or a concept of “users.” A bit of functionality I wanted to add was saving favorite trails. I didn’t want to be hacky about it, I needed some way to add users and a database. I knew it’d be hard for the developers to set this up as part of the API, they had their hands full with all the #soil-soil-soil-soil-soil (a slack channel dedicated solely to figuring out our soil data problem—those were plentiful.) I had been looking for an excuse to use Userbase, and this seemed like as good a time as any. A textbook Userbase use case “When would I use it?” The Usebase site lists these reasons: If you want to build a web app without writing any backend code. If you never want to see your users' data. If you're tired of dealing with databases. If you want to radically simplify your GDPR compliance. And if you want to keep things really simple. This was a perfect fit for my problem. I didn’t want to write any more backend code for this. I didn’t want to see our user’s data, I don’t care to know anyone’s favorite trails.* A nice bonus to not having users in our backend was not having to worry about keeping their data safe. We don’t have their data at all, it’s end-to-end encrypted by Userbase. We can offer a reasonable amount of privacy for free (well for the price of using Userbase: $49 a year.) I am not tired of dealing with databases, but I’d rather not. I don’t think anyone doesn’t want to simplify their GDPR compliance. Finally, given our tight timeline I wanted nothing more than to keep things really simple. A sign up form that I didn't have to write a back-end for Using Userbase Userbase can be tried for free, so I set aside thirty minutes or so to do a quick proof of concept to make sure this would work out for us. I made an account and followed their Quickstart. Userbase is a fundamentally easy tool to use, but their quickstart is everything I’d want out of a quickstart: Written in the most vanilla way possible (just HTML and vanilla JS). This means I can adapt it to my needs, in this case React using Next.js Easy to follow, it does the most barebones tour of the functionality you can expect to get out of the SDK (software development kit.) In other words it is quick and it is a start It has a live demo and code samples you can download and run yourself It didn’t take long after that to integrate Userbase into our app with more help from their great docs. I debated whether to add code samples of what we did here, and I didn’t because any reader would be better off using the great quickstart and docs Userbase provides—they are that clear, and that good. Depending on your use case you’ll need to adapt the examples to your needs, for us the trickiest things were creating a top level authentication context to manage users in the app, and a custom hook to encapsulate all the logic for setting, updating, and deleting favourite trails in the app. Userbase’s SDK worked seamlessly for us. A log in form that I didn't have to write a back-end for Is Userbase for you? Maybe. I am definitely a fan, so much so that this blog post probably reads like an advert. Userbase saved me a ton of time in this project. It reminded me of “The All Powerful Front End Developer” talk by Chris Coyer. I don’t fully subscribe to all the ideas in that talk, but it is nice to have “serverless” tools like Userbase, and all the new JAMstacky things. There are limits to the Userbase serverless experience in terms of scale, and control. Obviously relying on a third party for something always carries some (probably small) risk—it’s worth noting Usebase includes a note on their pricing page that says “You can host it yourself always under your control, or we can run it for you for a full serverless experience”—Still, I wouldn’t hesitate this to use in future projects. One of the great things about Viget and Pointless Weekend is the opportunity to try new things. For me that was Next.js and Userbase for Trailbuddy. It doesn’t always work out (in fact this is my first pointless weekend where a risk hasn’t blown up in my face) but it is always fun. Getting to try out Userbase and beginning to think about how we may use it in the future made the weekend worthwhile for me, and it made my job on this project much more enjoyable. *I will write a future post about privacy conscious analytics in TrailBuddy when I’ve figured that out. I am looking into Fathom Analytics for that. Full Article Code Front-end Engineering
ba Global Gitignore Files Are Cool and So Are You By feedproxy.google.com Published On :: Wed, 06 May 2020 08:00:00 -0400 Setting it up First, here's the config setup you need to even allow for such a radical concept. Define the global gitignore file as a global Git configuration: git config --global core.excludesfile ~/.gitignore If you're on OSX, this command will add the following config lines in your ~/.gitconfig file. [core] excludesfile = /Users/triplegirldad/.gitignore Load that ~/.gitignore file up with whatever you want. It probably doesn't exist as a file yet so you might have to create it first. Harnessing its incredible power There are only two lines in my global gitignore file and they are both fairly useful pretty much all the time. $ cat ~/.gitignore TODO.md playground This 2 line file means that no matter where I am, what project I'm working on, where in the project I'm doing so, I have an easy space to stash notes, thoughts, in progress ideas, spikes, etc. TODO.md More often than not, I'm fiddling around with a TODO.md file. Something about writing markdown in your familiar text editor speaks to my soul. It's quick, it's easy, you have all the text editing tricks available to you, and it never does anything you wouldn't expect (looking at you auto-markdown-formatting editors). I use one or two # for headings, I use nested lists, and I ask for nothing more. Nothing more than more TODO.md files that is! In practice I tend to just have one TODO.md file per project, right at the top, ready to pull up in a few keystrokes. Which I do often. I pull this doc up if: I'm in a meeting and I just said "oh yeah that's a small thing, I'll knock it out this afternoon". I'm halfway through some feature development and realize I want to make a sweeping refactor elsewhere. Toss some thoughts in the doc, and then get back to the task at hand. It's the end of the day and I have to switch my brain into "feed small children" mode, thus obliterating everything work-related from my short term memory. When I open things up the next day and know exactly what the next thing to dive into was. I'm preparing for a big enough refactor and I can't hold it all in my brain at once. What I'd give to have an interactive 3D playground for brain thoughts, but in the meantime a 2D text file isn't a terrible way to plan out dev work. playground Sometimes you need more than some human words in a markdown file to move an idea along. This is where my playground directory comes in. I can load this directory up with code that's related to a given project and keep it out of the git history. Because who doesn't like a place to play around. I find that this directory is more useful for long running maintenance projects over fast moving greenfield ones. On the maintenance projects, I tend to find myself assembling a pile of scripts and experiments for various situations: The client requests a one-time obscure data export. Whip up some CSV generation code and save that code in the playground directory. The client requests a different obscure data export. Pull up the last time you did something vaguely similar and save yourself the startup time. A batch of data needs to be imported just once. Might as well stash that in the chance that "just once" is actually "just a few times". Kicking the tires on an integration with a third party service. Some of these playground files end up being useful more times than I can count (eg: the ever-changing user_export.rb script). Some items get promoted into application code, which is always fun. But most files here serve their purpose and then wither away. And that's fine. It's a playground, anything goes. Wrapping up Having a personal space for project-specific notes and code has been helpful to me over the years as a developer on multiple projects. If you have your own organizational trick, or just want to brag about how you memorize everything without any markdown files, let me know in the comments below! Full Article Code
ba 240 Basic Icons Vector Freebie By feedproxy.google.com Published On :: Sat, 30 Dec 2017 19:53:50 +0000 Flat design is everywhere. Nowadays aesthetics is a lot more simple. No more glossy buttons or gradients background, or what a about the shiny table effect every client asked for?.It is all gone now. In favor of a more “undesigned” look a back to basics trend. Following that idea the guys at your favorite resources … 240 Basic Icons Vector Freebie Read More » Full Article Freebies
ba How To Build A Vue Survey App Using Firebase Authentication And Database By feedproxy.google.com Published On :: Fri, 08 May 2020 11:00:00 +0000 In this tutorial, you’ll be building a Survey App, where we’ll learn to validate our users form data, implement Authentication in Vue, and be able to receive survey data using Vue and Firebase (a BaaS platform). As we build this app, we’ll be learning how to handle form validation for different kinds of data, including reaching out to the backend to check if an email is already taken, even before the user submits the form during sign up. Full Article
ba Output feedback stochastic MPC with packet losses. (arXiv:2004.02591v2 [math.OC] UPDATED) By arxiv.org Published On :: The paper considers constrained linear systems with stochastic additive disturbances and noisy measurements transmitted over a lossy communication channel. We propose a model predictive control (MPC) law that minimizes a discounted cost subject to a discounted expectation constraint. Sensor data is assumed to be lost with known probability, and data losses are accounted for by expressing the predicted control policy as an affine function of future observations, which results in a convex optimal control problem. An online constraint-tightening technique ensures recursive feasibility of the online optimization and satisfaction of the expectation constraint without bounds on the distributions of the noise and disturbance inputs. The cost evaluated along trajectories of the closed loop system is shown to be bounded by the optimal predicted cost. A numerical example is given to illustrate these results. Full Article
ba Set theoretic Yang-Baxter & reflection equations and quantum group symmetries. (arXiv:2003.08317v3 [math-ph] UPDATED) By arxiv.org Published On :: Connections between set theoretic Yang-Baxter and reflection equations and quantum integrable systems are investigated. We show that set theoretic $R$-matrices are expressed as twists of known solutions. We then focus on reflection and twisted algebras and we derive the associated defining algebra relations for $R$-matrices being Baxterized solutions of the $A$-type Hecke algebra ${cal H}_N(q=1)$. We show in the case of the reflection algebra that there exists a "boundary" finite sub-algebra for some special choice of "boundary" elements of the $B$-type Hecke algebra ${cal B}_N(q=1, Q)$. We also show the key proposition that the associated double row transfer matrix is essentially expressed in terms of the elements of the $B$-type Hecke algebra. This is one of the fundamental results of this investigation together with the proof of the duality between the boundary finite subalgebra and the $B$-type Hecke algebra. These are universal statements that largely generalize previous relevant findings, and also allow the investigation of the symmetries of the double row transfer matrix. Full Article
ba Solitary wave solutions and global well-posedness for a coupled system of gKdV equations. (arXiv:2002.09531v2 [math.AP] UPDATED) By arxiv.org Published On :: In this work we consider the initial-value problem associated with a coupled system of generalized Korteweg-de Vries equations. We present a relationship between the best constant for a Gagliardo-Nirenberg type inequality and a criterion for the existence of global solutions in the energy space. We prove that such a constant is directly related to the existence problem of solitary-wave solutions with minimal mass, the so called ground state solutions. To guarantee the existence of ground states we use a variational method. Full Article
ba Three-point Functions in $mathcal{N}=4$ SYM at Finite $N_c$ and Background Independence. (arXiv:2002.07216v2 [hep-th] UPDATED) By arxiv.org Published On :: We compute non-extremal three-point functions of scalar operators in $mathcal{N}=4$ super Yang-Mills at tree-level in $g_{YM}$ and at finite $N_c$, using the operator basis of the restricted Schur characters. We make use of the diagrammatic methods called quiver calculus to simplify the three-point functions. The results involve an invariant product of the generalized Racah-Wigner tensors ($6j$ symbols). Assuming that the invariant product is written by the Littlewood-Richardson coefficients, we show that the non-extremal three-point functions satisfy the large $N_c$ background independence; correspondence between the string excitations on $AdS_5 imes S^5$ and those in the LLM geometry. Full Article
ba Unbounded Kobayashi hyperbolic domains in $mathbb C^n$. (arXiv:1911.05632v2 [math.CV] UPDATED) By arxiv.org Published On :: We first give a sufficient condition, issued from pluripotential theory, for an unbounded domain in the complex Euclidean space $mathbb C^n$ to be Kobayashi hyperbolic. Then, we construct an example of a rigid pseudoconvex domain in $mathbb C^3$ that is Kobayashi hyperbolic and has a nonempty core. In particular, this domain is not biholomorphic to a bounded domain in $mathbb C^3$ and the mentioned above sufficient condition for Kobayashi hyperbolicity is not necessary. Full Article
ba Equivariant Batalin-Vilkovisky formalism. (arXiv:1907.07995v3 [hep-th] UPDATED) By arxiv.org Published On :: We study an equivariant extension of the Batalin-Vilkovisky formalism for quantizing gauge theories. Namely, we introduce a general framework to encompass failures of the quantum master equation, and we apply it to the natural equivariant extension of AKSZ solutions of the classical master equation (CME). As examples of the construction, we recover the equivariant extension of supersymmetric Yang-Mills in 2d and of Donaldson-Witten theory. Full Article
ba Grothendieck's inequalities for JB$^*$-triples: Proof of the Barton-Friedman conjecture. (arXiv:1903.08931v3 [math.OA] UPDATED) By arxiv.org Published On :: We prove that, given a constant $K> 2$ and a bounded linear operator $T$ from a JB$^*$-triple $E$ into a complex Hilbert space $H$, there exists a norm-one functional $psiin E^*$ satisfying $$|T(x)| leq K , |T| , |x|_{psi},$$ for all $xin E$. Applying this result we show that, given $G > 8 (1+2sqrt{3})$ and a bounded bilinear form $V$ on the Cartesian product of two JB$^*$-triples $E$ and $B$, there exist norm-one functionals $varphiin E^{*}$ and $psiin B^{*}$ satisfying $$|V(x,y)| leq G |V| , |x|_{varphi} , |y|_{psi}$$ for all $(x,y)in E imes B$. These results prove a conjecture pursued during almost twenty years. Full Article
ba A Forward-Backward Splitting Method for Monotone Inclusions Without Cocoercivity. (arXiv:1808.04162v4 [math.OC] UPDATED) By arxiv.org Published On :: In this work, we propose a simple modification of the forward-backward splitting method for finding a zero in the sum of two monotone operators. Our method converges under the same assumptions as Tseng's forward-backward-forward method, namely, it does not require cocoercivity of the single-valued operator. Moreover, each iteration only requires one forward evaluation rather than two as is the case for Tseng's method. Variants of the method incorporating a linesearch, relaxation and inertia, or a structured three operator inclusion are also discussed. Full Article
ba Extremal values of the Sackin balance index for rooted binary trees. (arXiv:1801.10418v5 [q-bio.PE] UPDATED) By arxiv.org Published On :: Tree balance plays an important role in different research areas like theoretical computer science and mathematical phylogenetics. For example, it has long been known that under the Yule model, a pure birth process, imbalanced trees are more likely than balanced ones. Therefore, different methods to measure the balance of trees were introduced. The Sackin index is one of the most frequently used measures for this purpose. In many contexts, statements about the minimal and maximal values of this index have been discussed, but formal proofs have never been provided. Moreover, while the number of trees with maximal Sackin index as well as the number of trees with minimal Sackin index when the number of leaves is a power of 2 are relatively easy to understand, the number of trees with minimal Sackin index for all other numbers of leaves was completely unknown. In this manuscript, we fully characterize trees with minimal and maximal Sackin index and also provide formulas to explicitly calculate the number of such trees. Full Article
ba Expansion of Iterated Stratonovich Stochastic Integrals of Arbitrary Multiplicity Based on Generalized Iterated Fourier Series Converging Pointwise. (arXiv:1801.00784v9 [math.PR] UPDATED) By arxiv.org Published On :: The article is devoted to the expansion of iterated Stratonovich stochastic integrals of arbitrary multiplicity $k$ $(kinmathbb{N})$ based on the generalized iterated Fourier series. The case of Fourier-Legendre series as well as the case of trigonotemric Fourier series are considered in details. The obtained expansion provides a possibility to represent the iterated Stratonovich stochastic integral in the form of iterated series of products of standard Gaussian random variables. Convergence in the mean of degree $2n$ $(nin mathbb{N})$ of the expansion is proved. Some modifications of the mentioned expansion were derived for the case $k=2$. One of them is based of multiple trigonomentric Fourier series converging almost everywhere in the square $[t, T]^2$. The results of the article can be applied to the numerical solution of Ito stochastic differential equations. Full Article
ba Simulation of Integro-Differential Equation and Application in Estimation of Ruin Probability with Mixed Fractional Brownian Motion. (arXiv:1709.03418v6 [math.PR] UPDATED) By arxiv.org Published On :: In this paper, we are concerned with the numerical solution of one type integro-differential equation by a probability method based on the fundamental martingale of mixed Gaussian processes. As an application, we will try to simulate the estimation of ruin probability with an unknown parameter driven not by the classical L'evy process but by the mixed fractional Brownian motion. Full Article
ba Special subvarieties of non-arithmetic ball quotients and Hodge Theory. (arXiv:2005.03524v1 [math.AG]) By arxiv.org Published On :: Let $Gamma subset operatorname{PU}(1,n)$ be a lattice, and $S_Gamma$ the associated ball quotient. We prove that, if $S_Gamma$ contains infinitely many maximal totally geodesic subvarieties, then $Gamma$ is arithmetic. We also prove an Ax-Schanuel Conjecture for $S_Gamma$, similar to the one recently proven by Mok, Pila and Tsimerman. One of the main ingredients in the proofs is to realise $S_Gamma$ inside a period domain for polarised integral variations of Hodge structures and interpret totally geodesic subvarieties as unlikely intersections. Full Article
ba Semiglobal non-oscillatory big bang singular spacetimes for the Einstein-scalar field system. (arXiv:2005.03395v1 [math-ph]) By arxiv.org Published On :: We construct semiglobal singular spacetimes for the Einstein equations coupled to a massless scalar field. Consistent with the heuristic analysis of Belinskii, Khalatnikov, Lifshitz or BKL for this system, there are no oscillations due to the scalar field. (This is much simpler than the oscillatory BKL heuristics for the Einstein vacuum equations.) Prior results are due to Andersson and Rendall in the real analytic case, and Rodnianski and Speck in the smooth near-spatially-flat-FLRW case. Similar to Andersson and Rendall we give asymptotic data at the singularity, which we refer to as final data, but our construction is not limited to real analytic solutions. This paper is a test application of tools (a graded Lie algebra formulation of the Einstein equations and a filtration) intended for the more subtle vacuum case. We use homological algebra tools to construct a formal series solution, then symmetric hyperbolic energy estimates to construct a true solution well-approximated by truncations of the formal one. We conjecture that the image of the map from final data to initial data is an open set of anisotropic initial data. Full Article
ba Converging outer approximations to global attractors using semidefinite programming. (arXiv:2005.03346v1 [math.OC]) By arxiv.org Published On :: This paper develops a method for obtaining guaranteed outer approximations for global attractors of continuous and discrete time nonlinear dynamical systems. The method is based on a hierarchy of semidefinite programming problems of increasing size with guaranteed convergence to the global attractor. The approach taken follows an established line of reasoning, where we first characterize the global attractor via an infinite dimensional linear programming problem (LP) in the space of Borel measures. The dual to this LP is in the space of continuous functions and its feasible solutions provide guaranteed outer approximations to the global attractor. For systems with polynomial dynamics, a hierarchy of finite-dimensional sum-of-squares tightenings of the dual LP provides a sequence of outer approximations to the global attractor with guaranteed convergence in the sense of volume discrepancy tending to zero. The method is very simple to use and based purely on convex optimization. Numerical examples with the code available online demonstrate the method. Full Article
ba Exponential decay for negative feedback loop with distributed delay. (arXiv:2005.03136v1 [math.DS]) By arxiv.org Published On :: We derive sufficient conditions for exponential decay of solutions of the delay negative feedback equation with distributed delay. The conditions are written in terms of exponential moments of the distribution. Our method only uses elementary tools of calculus and is robust towards possible extensions to more complex settings, in particular, systems of delay differential equations. We illustrate the applicability of the method to particular distributions - Dirac delta, Gamma distribution, uniform and truncated normal distributions. Full Article
ba GraphBLAST: A High-Performance Linear Algebra-based Graph Framework on the GPU. (arXiv:1908.01407v3 [cs.DC] CROSS LISTED) By arxiv.org Published On :: High-performance implementations of graph algorithms are challenging to implement on new parallel hardware such as GPUs, because of three challenges: (1) difficulty of coming up with graph building blocks, (2) load imbalance on parallel hardware, and (3) graph problems having low arithmetic intensity. To address these challenges, GraphBLAS is an innovative, on-going effort by the graph analytics community to propose building blocks based in sparse linear algebra, which will allow graph algorithms to be expressed in a performant, succinct, composable and portable manner. In this paper, we examine the performance challenges of a linear algebra-based approach to building graph frameworks and describe new design principles for overcoming these bottlenecks. Among the new design principles is exploiting input sparsity, which allows users to write graph algorithms without specifying push and pull direction. Exploiting output sparsity allows users to tell the backend which values of the output in a single vectorized computation they do not want computed. Load-balancing is an important feature for balancing work amongst parallel workers. We describe the important load-balancing features for handling graphs with different characteristics. The design principles described in this paper have been implemented in "GraphBLAST", the first open-source linear algebra-based graph framework on GPU targeting high-performance computing. The results show that on a single GPU, GraphBLAST has on average at least an order of magnitude speedup over previous GraphBLAS implementations SuiteSparse and GBTL, comparable performance to the fastest GPU hardwired primitives and shared-memory graph frameworks Ligra and Gunrock, and better performance than any other GPU graph framework, while offering a simpler and more concise programming model. Full Article
ba Temporal Event Segmentation using Attention-based Perceptual Prediction Model for Continual Learning. (arXiv:2005.02463v2 [cs.CV] UPDATED) By arxiv.org Published On :: Temporal event segmentation of a long video into coherent events requires a high level understanding of activities' temporal features. The event segmentation problem has been tackled by researchers in an offline training scheme, either by providing full, or weak, supervision through manually annotated labels or by self-supervised epoch based training. In this work, we present a continual learning perceptual prediction framework (influenced by cognitive psychology) capable of temporal event segmentation through understanding of the underlying representation of objects within individual frames. Our framework also outputs attention maps which effectively localize and track events-causing objects in each frame. The model is tested on a wildlife monitoring dataset in a continual training manner resulting in $80\%$ recall rate at $20\%$ false positive rate for frame level segmentation. Activity level testing has yielded $80\%$ activity recall rate for one false activity detection every 50 minutes. Full Article
ba The Sensitivity of Language Models and Humans to Winograd Schema Perturbations. (arXiv:2005.01348v2 [cs.CL] UPDATED) By arxiv.org Published On :: Large-scale pretrained language models are the major driving force behind recent improvements in performance on the Winograd Schema Challenge, a widely employed test of common sense reasoning ability. We show, however, with a new diagnostic dataset, that these models are sensitive to linguistic perturbations of the Winograd examples that minimally affect human understanding. Our results highlight interesting differences between humans and language models: language models are more sensitive to number or gender alternations and synonym replacements than humans, and humans are more stable and consistent in their predictions, maintain a much higher absolute performance, and perform better on non-associative instances than associative ones. Overall, humans are correct more often than out-of-the-box models, and the models are sometimes right for the wrong reasons. Finally, we show that fine-tuning on a large, task-specific dataset can offer a solution to these issues. Full Article
ba Quantum arithmetic operations based on quantum Fourier transform on signed integers. (arXiv:2005.00443v2 [cs.IT] UPDATED) By arxiv.org Published On :: The quantum Fourier transform brings efficiency in many respects, especially usage of resource, for most operations on quantum computers. In this study, the existing QFT-based and non-QFT-based quantum arithmetic operations are examined. The capabilities of QFT-based addition and multiplication are improved with some modifications. The proposed operations are compared with the nearest quantum arithmetic operations. Furthermore, novel QFT-based subtraction and division operations are presented. The proposed arithmetic operations can perform non-modular operations on all signed numbers without any limitation by using less resources. In addition, novel quantum circuits of two's complement, absolute value and comparison operations are also presented by using the proposed QFT based addition and subtraction operations. Full Article
ba On-board Deep-learning-based Unmanned Aerial Vehicle Fault Cause Detection and Identification. (arXiv:2005.00336v2 [eess.SP] UPDATED) By arxiv.org Published On :: With the increase in use of Unmanned Aerial Vehicles (UAVs)/drones, it is important to detect and identify causes of failure in real time for proper recovery from a potential crash-like scenario or post incident forensics analysis. The cause of crash could be either a fault in the sensor/actuator system, a physical damage/attack, or a cyber attack on the drone's software. In this paper, we propose novel architectures based on deep Convolutional and Long Short-Term Memory Neural Networks (CNNs and LSTMs) to detect (via Autoencoder) and classify drone mis-operations based on sensor data. The proposed architectures are able to learn high-level features automatically from the raw sensor data and learn the spatial and temporal dynamics in the sensor data. We validate the proposed deep-learning architectures via simulations and experiments on a real drone. Empirical results show that our solution is able to detect with over 90% accuracy and classify various types of drone mis-operations (with about 99% accuracy (simulation data) and upto 88% accuracy (experimental data)). Full Article
ba Transfer Learning for EEG-Based Brain-Computer Interfaces: A Review of Progress Made Since 2016. (arXiv:2004.06286v3 [cs.HC] UPDATED) By arxiv.org Published On :: A brain-computer interface (BCI) enables a user to communicate with a computer directly using brain signals. Electroencephalograms (EEGs) used in BCIs are weak, easily contaminated by interference and noise, non-stationary for the same subject, and varying across different subjects and sessions. Therefore, it is difficult to build a generic pattern recognition model in an EEG-based BCI system that is optimal for different subjects, during different sessions, for different devices and tasks. Usually, a calibration session is needed to collect some training data for a new subject, which is time consuming and user unfriendly. Transfer learning (TL), which utilizes data or knowledge from similar or relevant subjects/sessions/devices/tasks to facilitate learning for a new subject/session/device/task, is frequently used to reduce the amount of calibration effort. This paper reviews journal publications on TL approaches in EEG-based BCIs in the last few years, i.e., since 2016. Six paradigms and applications -- motor imagery, event-related potentials, steady-state visual evoked potentials, affective BCIs, regression problems, and adversarial attacks -- are considered. For each paradigm/application, we group the TL approaches into cross-subject/session, cross-device, and cross-task settings and review them separately. Observations and conclusions are made at the end of the paper, which may point to future research directions. Full Article
ba Novel Deep Learning Framework for Wideband Spectrum Characterization at Sub-Nyquist Rate. (arXiv:1912.05255v2 [eess.SP] UPDATED) By arxiv.org Published On :: Introduction of spectrum-sharing in 5G and subsequent generation networks demand base-station(s) with the capability to characterize the wideband spectrum spanned over licensed, shared and unlicensed non-contiguous frequency bands. Spectrum characterization involves the identification of vacant bands along with center frequency and parameters (energy, modulation, etc.) of occupied bands. Such characterization at Nyquist sampling is area and power-hungry due to the need for high-speed digitization. Though sub-Nyquist sampling (SNS) offers an excellent alternative when the spectrum is sparse, it suffers from poor performance at low signal to noise ratio (SNR) and demands careful design and integration of digital reconstruction, tunable channelizer and characterization algorithms. In this paper, we propose a novel deep-learning framework via a single unified pipeline to accomplish two tasks: 1)~Reconstruct the signal directly from sub-Nyquist samples, and 2)~Wideband spectrum characterization. The proposed approach eliminates the need for complex signal conditioning between reconstruction and characterization and does not need complex tunable channelizers. We extensively compare the performance of our framework for a wide range of modulation schemes, SNR and channel conditions. We show that the proposed framework outperforms existing SNS based approaches and characterization performance approaches to Nyquist sampling-based framework with an increase in SNR. Easy to design and integrate along with a single unified deep learning framework make the proposed architecture a good candidate for reconfigurable platforms. Full Article
ba Two-Stream FCNs to Balance Content and Style for Style Transfer. (arXiv:1911.08079v2 [cs.CV] UPDATED) By arxiv.org Published On :: Style transfer is to render given image contents in given styles, and it has an important role in both computer vision fundamental research and industrial applications. Following the success of deep learning based approaches, this problem has been re-launched recently, but still remains a difficult task because of trade-off between preserving contents and faithful rendering of styles. Indeed, how well-balanced content and style are is crucial in evaluating the quality of stylized images. In this paper, we propose an end-to-end two-stream Fully Convolutional Networks (FCNs) aiming at balancing the contributions of the content and the style in rendered images. Our proposed network consists of the encoder and decoder parts. The encoder part utilizes a FCN for content and a FCN for style where the two FCNs have feature injections and are independently trained to preserve the semantic content and to learn the faithful style representation in each. The semantic content feature and the style representation feature are then concatenated adaptively and fed into the decoder to generate style-transferred (stylized) images. In order to train our proposed network, we employ a loss network, the pre-trained VGG-16, to compute content loss and style loss, both of which are efficiently used for the feature injection as well as the feature concatenation. Our intensive experiments show that our proposed model generates more balanced stylized images in content and style than state-of-the-art methods. Moreover, our proposed network achieves efficiency in speed. Full Article
ba Global Locality in Biomedical Relation and Event Extraction. (arXiv:1909.04822v2 [cs.CL] UPDATED) By arxiv.org Published On :: Due to the exponential growth of biomedical literature, event and relation extraction are important tasks in biomedical text mining. Most work only focus on relation extraction, and detect a single entity pair mention on a short span of text, which is not ideal due to long sentences that appear in biomedical contexts. We propose an approach to both relation and event extraction, for simultaneously predicting relationships between all mention pairs in a text. We also perform an empirical study to discuss different network setups for this purpose. The best performing model includes a set of multi-head attentions and convolutions, an adaptation of the transformer architecture, which offers self-attention the ability to strengthen dependencies among related elements, and models the interaction between features extracted by multiple attention heads. Experiment results demonstrate that our approach outperforms the state of the art on a set of benchmark biomedical corpora including BioNLP 2009, 2011, 2013 and BioCreative 2017 shared tasks. Full Article
ba The Mapillary Traffic Sign Dataset for Detection and Classification on a Global Scale. (arXiv:1909.04422v2 [cs.CV] UPDATED) By arxiv.org Published On :: Traffic signs are essential map features globally in the era of autonomous driving and smart cities. To develop accurate and robust algorithms for traffic sign detection and classification, a large-scale and diverse benchmark dataset is required. In this paper, we introduce a traffic sign benchmark dataset of 100K street-level images around the world that encapsulates diverse scenes, wide coverage of geographical locations, and varying weather and lighting conditions and covers more than 300 manually annotated traffic sign classes. The dataset includes 52K images that are fully annotated and 48K images that are partially annotated. This is the largest and the most diverse traffic sign dataset consisting of images from all over world with fine-grained annotations of traffic sign classes. We have run extensive experiments to establish strong baselines for both the detection and the classification tasks. In addition, we have verified that the diversity of this dataset enables effective transfer learning for existing large-scale benchmark datasets on traffic sign detection and classification. The dataset is freely available for academic research: https://www.mapillary.com/dataset/trafficsign. Full Article
ba A Fast and Accurate Algorithm for Spherical Harmonic Analysis on HEALPix Grids with Applications to the Cosmic Microwave Background Radiation. (arXiv:1904.10514v4 [math.NA] UPDATED) By arxiv.org Published On :: The Hierarchical Equal Area isoLatitude Pixelation (HEALPix) scheme is used extensively in astrophysics for data collection and analysis on the sphere. The scheme was originally designed for studying the Cosmic Microwave Background (CMB) radiation, which represents the first light to travel during the early stages of the universe's development and gives the strongest evidence for the Big Bang theory to date. Refined analysis of the CMB angular power spectrum can lead to revolutionary developments in understanding the nature of dark matter and dark energy. In this paper, we present a new method for performing spherical harmonic analysis for HEALPix data, which is a central component to computing and analyzing the angular power spectrum of the massive CMB data sets. The method uses a novel combination of a non-uniform fast Fourier transform, the double Fourier sphere method, and Slevinsky's fast spherical harmonic transform (Slevinsky, 2019). For a HEALPix grid with $N$ pixels (points), the computational complexity of the method is $mathcal{O}(Nlog^2 N)$, with an initial set-up cost of $mathcal{O}(N^{3/2}log N)$. This compares favorably with $mathcal{O}(N^{3/2})$ runtime complexity of the current methods available in the HEALPix software when multiple maps need to be analyzed at the same time. Using numerical experiments, we demonstrate that the new method also appears to provide better accuracy over the entire angular power spectrum of synthetic data when compared to the current methods, with a convergence rate at least two times higher. Full Article
ba Constrained Restless Bandits for Dynamic Scheduling in Cyber-Physical Systems. (arXiv:1904.08962v3 [cs.SY] UPDATED) By arxiv.org Published On :: Restless multi-armed bandits are a class of discrete-time stochastic control problems which involve sequential decision making with a finite set of actions (set of arms). This paper studies a class of constrained restless multi-armed bandits (CRMAB). The constraints are in the form of time varying set of actions (set of available arms). This variation can be either stochastic or semi-deterministic. Given a set of arms, a fixed number of them can be chosen to be played in each decision interval. The play of each arm yields a state dependent reward. The current states of arms are partially observable through binary feedback signals from arms that are played. The current availability of arms is fully observable. The objective is to maximize long term cumulative reward. The uncertainty about future availability of arms along with partial state information makes this objective challenging. Applications for CRMAB abound in the domain of cyber-physical systems. This optimization problem is analyzed using Whittle's index policy. To this end, a constrained restless single-armed bandit is studied. It is shown to admit a threshold-type optimal policy, and is also indexable. An algorithm to compute Whittle's index is presented. Further, upper bounds on the value function are derived in order to estimate the degree of sub-optimality of various solutions. The simulation study compares the performance of Whittle's index, modified Whittle's index and myopic policies. Full Article
ba Defending Hardware-based Malware Detectors against Adversarial Attacks. (arXiv:2005.03644v1 [cs.CR]) By arxiv.org Published On :: In the era of Internet of Things (IoT), Malware has been proliferating exponentially over the past decade. Traditional anti-virus software are ineffective against modern complex Malware. In order to address this challenge, researchers have proposed Hardware-assisted Malware Detection (HMD) using Hardware Performance Counters (HPCs). The HPCs are used to train a set of Machine learning (ML) classifiers, which in turn, are used to distinguish benign programs from Malware. Recently, adversarial attacks have been designed by introducing perturbations in the HPC traces using an adversarial sample predictor to misclassify a program for specific HPCs. These attacks are designed with the basic assumption that the attacker is aware of the HPCs being used to detect Malware. Since modern processors consist of hundreds of HPCs, restricting to only a few of them for Malware detection aids the attacker. In this paper, we propose a Moving target defense (MTD) for this adversarial attack by designing multiple ML classifiers trained on different sets of HPCs. The MTD randomly selects a classifier; thus, confusing the attacker about the HPCs or the number of classifiers applied. We have developed an analytical model which proves that the probability of an attacker to guess the perfect HPC-classifier combination for MTD is extremely low (in the range of $10^{-1864}$ for a system with 20 HPCs). Our experimental results prove that the proposed defense is able to improve the classification accuracy of HPC traces that have been modified through an adversarial sample generator by up to 31.5%, for a near perfect (99.4%) restoration of the original accuracy. Full Article
ba Seismic Shot Gather Noise Localization Using a Multi-Scale Feature-Fusion-Based Neural Network. (arXiv:2005.03626v1 [cs.CV]) By arxiv.org Published On :: Deep learning-based models, such as convolutional neural networks, have advanced various segments of computer vision. However, this technology is rarely applied to seismic shot gather noise localization problem. This letter presents an investigation on the effectiveness of a multi-scale feature-fusion-based network for seismic shot-gather noise localization. Herein, we describe the following: (1) the construction of a real-world dataset of seismic noise localization based on 6,500 seismograms; (2) a multi-scale feature-fusion-based detector that uses the MobileNet combined with the Feature Pyramid Net as the backbone; and (3) the Single Shot multi-box detector for box classification/regression. Additionally, we propose the use of the Focal Loss function that improves the detector's prediction accuracy. The proposed detector achieves an AP@0.5 of 78.67\% in our empirical evaluation. Full Article
ba COVID-19 Contact-tracing Apps: A Survey on the Global Deployment and Challenges. (arXiv:2005.03599v1 [cs.CR]) By arxiv.org Published On :: In response to the coronavirus disease (COVID-19) outbreak, there is an ever-increasing number of national governments that are rolling out contact-tracing Apps to aid the containment of the virus. The first hugely contentious issue facing the Apps is the deployment framework, i.e. centralised or decentralised. Based on this, the debate branches out to the corresponding technologies that underpin these architectures, i.e. GPS, QR codes, and Bluetooth. This work conducts a pioneering review of the above scenarios and contributes a geolocation mapping of the current deployment. The vulnerabilities and the directions of research are identified, with a special focus on the Bluetooth-based decentralised scheme. Full Article
ba VM placement over WDM-TDM AWGR PON Based Data Centre Architecture. (arXiv:2005.03590v1 [cs.NI]) By arxiv.org Published On :: Passive optical networks (PON) can play a vital role in data centres and access fog solutions by providing scalable, cost and energy efficient architectures. This paper proposes a Mixed Integer Linear Programming (MILP) model to optimize the placement of virtual machines (VMs) over an energy efficient WDM-TDM AWGR PON based data centre architecture. In this optimization, the use of VMs and their requirements affect the optimum number of servers utilized in the data centre when minimizing the power consumption and enabling more efficient utilization of servers is considered. Two power consumption minimization objectives were examined for up to 20 VMs with different computing and networking requirements. The results indicate that considering the minimization of the processing and networking power consumption in the allocation of VMs in the WDM-TDM AWGR PON can reduce the networking power consumption by up to 70% compared to the minimization of the processing power consumption. Full Article
ba A Reduced Basis Method For Fractional Diffusion Operators II. (arXiv:2005.03574v1 [math.NA]) By arxiv.org Published On :: We present a novel numerical scheme to approximate the solution map $smapsto u(s) := mathcal{L}^{-s}f$ to partial differential equations involving fractional elliptic operators. Reinterpreting $mathcal{L}^{-s}$ as interpolation operator allows us to derive an integral representation of $u(s)$ which includes solutions to parametrized reaction-diffusion problems. We propose a reduced basis strategy on top of a finite element method to approximate its integrand. Unlike prior works, we deduce the choice of snapshots for the reduced basis procedure analytically. Avoiding further discretization, the integral is interpreted in a spectral setting to evaluate the surrogate directly. Its computation boils down to a matrix approximation $L$ of the operator whose inverse is projected to a low-dimensional space, where explicit diagonalization is feasible. The universal character of the underlying $s$-independent reduced space allows the approximation of $(u(s))_{sin(0,1)}$ in its entirety. We prove exponential convergence rates and confirm the analysis with a variety of numerical examples. Further improvements are proposed in the second part of this investigation to avoid inversion of $L$. Instead, we directly project the matrix to the reduced space, where its negative fractional power is evaluated. A numerical comparison with the predecessor highlights its competitive performance. Full Article
ba QuickSync: A Quickly Synchronizing PoS-Based Blockchain Protocol. (arXiv:2005.03564v1 [cs.CR]) By arxiv.org Published On :: To implement a blockchain, we need a blockchain protocol for all the nodes to follow. To design a blockchain protocol, we need a block publisher selection mechanism and a chain selection rule. In Proof-of-Stake (PoS) based blockchain protocols, block publisher selection mechanism selects the node to publish the next block based on the relative stake held by the node. However, PoS protocols may face vulnerability to fully adaptive corruptions. In literature, researchers address this issue at the cost of performance. In this paper, we propose a novel PoS-based blockchain protocol, QuickSync, to achieve security against fully adaptive corruptions without compromising on performance. We propose a metric called block power, a value defined for each block, derived from the output of the verifiable random function based on the digital signature of the block publisher. With this metric, we compute chain power, the sum of block powers of all the blocks comprising the chain, for all the valid chains. These metrics are a function of the block publisher's stake to enable the PoS aspect of the protocol. The chain selection rule selects the chain with the highest chain power as the one to extend. This chain selection rule hence determines the selected block publisher of the previous block. When we use metrics to define the chain selection rule, it may lead to vulnerabilities against Sybil attacks. QuickSync uses a Sybil attack resistant function implemented using histogram matching. We prove that QuickSync satisfies common prefix, chain growth, and chain quality properties and hence it is secure. We also show that it is resilient to different types of adversarial attack strategies. Our analysis demonstrates that QuickSync performs better than Bitcoin by an order of magnitude on both transactions per second and time to finality, and better than Ouroboros v1 by a factor of three on time to finality. Full Article
ba Online Algorithms to Schedule a Proportionate Flexible Flow Shop of Batching Machines. (arXiv:2005.03552v1 [cs.DS]) By arxiv.org Published On :: This paper is the first to consider online algorithms to schedule a proportionate flexible flow shop of batching machines (PFFB). The scheduling model is motivated by manufacturing processes of individualized medicaments, which are used in modern medicine to treat some serious illnesses. We provide two different online algorithms, proving also lower bounds for the offline problem to compute their competitive ratios. The first algorithm is an easy-to-implement, general local scheduling heuristic. It is 2-competitive for PFFBs with an arbitrary number of stages and for several natural scheduling objectives. We also show that for total/average flow time, no deterministic algorithm with better competitive ratio exists. For the special case with two stages and the makespan or total completion time objective, we describe an improved algorithm that achieves the best possible competitive ratio $varphi=frac{1+sqrt{5}}{2}$, the golden ratio. All our results also hold for proportionate (non-flexible) flow shops of batching machines (PFB) for which this is also the first paper to study online algorithms. Full Article
ba CounQER: A System for Discovering and Linking Count Information in Knowledge Bases. (arXiv:2005.03529v1 [cs.IR]) By arxiv.org Published On :: Predicate constraints of general-purpose knowledge bases (KBs) like Wikidata, DBpedia and Freebase are often limited to subproperty, domain and range constraints. In this demo we showcase CounQER, a system that illustrates the alignment of counting predicates, like staffSize, and enumerating predicates, like workInstitution^{-1} . In the demonstration session, attendees can inspect these alignments, and will learn about the importance of these alignments for KB question answering and curation. CounQER is available at https://counqer.mpi-inf.mpg.de/spo. Full Article
ba Subquadratic-Time Algorithms for Normal Bases. (arXiv:2005.03497v1 [cs.SC]) By arxiv.org Published On :: For any finite Galois field extension $mathsf{K}/mathsf{F}$, with Galois group $G = mathrm{Gal}(mathsf{K}/mathsf{F})$, there exists an element $alpha in mathsf{K}$ whose orbit $Gcdotalpha$ forms an $mathsf{F}$-basis of $mathsf{K}$. Such an $alpha$ is called a normal element and $Gcdotalpha$ is a normal basis. We introduce a probabilistic algorithm for testing whether a given $alpha in mathsf{K}$ is normal, when $G$ is either a finite abelian or a metacyclic group. The algorithm is based on the fact that deciding whether $alpha$ is normal can be reduced to deciding whether $sum_{g in G} g(alpha)g in mathsf{K}[G]$ is invertible; it requires a slightly subquadratic number of operations. Once we know that $alpha$ is normal, we show how to perform conversions between the working basis of $mathsf{K}/mathsf{F}$ and the normal basis with the same asymptotic cost. Full Article
ba Ensuring Fairness under Prior Probability Shifts. (arXiv:2005.03474v1 [cs.LG]) By arxiv.org Published On :: In this paper, we study the problem of fair classification in the presence of prior probability shifts, where the training set distribution differs from the test set. This phenomenon can be observed in the yearly records of several real-world datasets, such as recidivism records and medical expenditure surveys. If unaccounted for, such shifts can cause the predictions of a classifier to become unfair towards specific population subgroups. While the fairness notion called Proportional Equality (PE) accounts for such shifts, a procedure to ensure PE-fairness was unknown. In this work, we propose a method, called CAPE, which provides a comprehensive solution to the aforementioned problem. CAPE makes novel use of prevalence estimation techniques, sampling and an ensemble of classifiers to ensure fair predictions under prior probability shifts. We introduce a metric, called prevalence difference (PD), which CAPE attempts to minimize in order to ensure PE-fairness. We theoretically establish that this metric exhibits several desirable properties. We evaluate the efficacy of CAPE via a thorough empirical evaluation on synthetic datasets. We also compare the performance of CAPE with several popular fair classifiers on real-world datasets like COMPAS (criminal risk assessment) and MEPS (medical expenditure panel survey). The results indicate that CAPE ensures PE-fair predictions, while performing well on other performance metrics. Full Article