rap Triangles in graphs without bipartite suspensions. (arXiv:2004.11930v2 [math.CO] UPDATED) By arxiv.org Published On :: Given graphs $T$ and $H$, the generalized Tur'an number ex$(n,T,H)$ is the maximum number of copies of $T$ in an $n$-vertex graph with no copies of $H$. Alon and Shikhelman, using a result of ErdH os, determined the asymptotics of ex$(n,K_3,H)$ when the chromatic number of $H$ is greater than 3 and proved several results when $H$ is bipartite. We consider this problem when $H$ has chromatic number 3. Even this special case for the following relatively simple 3-chromatic graphs appears to be challenging. The suspension $widehat H$ of a graph $H$ is the graph obtained from $H$ by adding a new vertex adjacent to all vertices of $H$. We give new upper and lower bounds on ex$(n,K_3,widehat{H})$ when $H$ is a path, even cycle, or complete bipartite graph. One of the main tools we use is the triangle removal lemma, but it is unclear if much stronger statements can be proved without using the removal lemma. Full Article
rap On the Asymptotic $u_0$-Expected Flooding Time of Stationary Edge-Markovian Graphs. (arXiv:2004.03660v4 [math.PR] UPDATED) By arxiv.org Published On :: Consider that $u_0$ nodes are aware of some piece of data $d_0$. This note derives the expected time required for the data $d_0$ to be disseminated through-out a network of $n$ nodes, when communication between nodes evolves according to a graphical Markov model $overline{ mathcal{G}}_{n,hat{p}}$ with probability parameter $hat{p}$. In this model, an edge between two nodes exists at discrete time $k in mathbb{N}^+$ with probability $hat{p}$ if this edge existed at $k-1$, and with probability $(1-hat{p})$ if this edge did not exist at $k-1$. Each edge is interpreted as a bidirectional communication link over which data between neighbors is shared. The initial communication graph is assumed to be an Erdos-Renyi random graph with parameters $(n,hat{p})$, hence we consider a emph{stationary} Markov model $overline{mathcal{G}}_{n,hat{p}}$. The asymptotic "$u_0$-expected flooding time" of $overline{mathcal{G}}_{n,hat{p}}$ is defined as the expected number of iterations required to transmit the data $d_0$ from $u_0$ nodes to $n$ nodes, in the limit as $n$ approaches infinity. Although most previous results on the asymptotic flooding time in graphical Markov models are either emph{almost sure} or emph{with high probability}, the bounds obtained here are emph{in expectation}. However, our bounds are tighter and can be more complete than previous results. Full Article
rap Monochromatic Equilateral Triangles in the Unit Distance Graph. (arXiv:1909.09856v2 [math.CO] UPDATED) By arxiv.org Published On :: Let $chi_{Delta}(mathbb{R}^{n})$ denote the minimum number of colors needed to color $mathbb{R}^{n}$ so that there will not be a monochromatic equilateral triangle with side length $1$. Using the slice rank method, we reprove a result of Frankl and Rodl, and show that $chi_{Delta}left(mathbb{R}^{n} ight)$ grows exponentially with $n$. This technique substantially improves upon the best known quantitative lower bounds for $chi_{Delta}left(mathbb{R}^{n} ight)$, and we obtain [ chi_{Delta}left(mathbb{R}^{n} ight)>(1.01446+o(1))^{n}. ] Full Article
rap $k$-Critical Graphs in $P_5$-Free Graphs. (arXiv:2005.03441v1 [math.CO]) By arxiv.org Published On :: Given two graphs $H_1$ and $H_2$, a graph $G$ is $(H_1,H_2)$-free if it contains no induced subgraph isomorphic to $H_1$ or $H_2$. Let $P_t$ be the path on $t$ vertices. A graph $G$ is $k$-vertex-critical if $G$ has chromatic number $k$ but every proper induced subgraph of $G$ has chromatic number less than $k$. The study of $k$-vertex-critical graphs for graph classes is an important topic in algorithmic graph theory because if the number of such graphs that are in a given hereditary graph class is finite, then there is a polynomial-time algorithm to decide if a graph in the class is $(k-1)$-colorable. In this paper, we initiate a systematic study of the finiteness of $k$-vertex-critical graphs in subclasses of $P_5$-free graphs. Our main result is a complete classification of the finiteness of $k$-vertex-critical graphs in the class of $(P_5,H)$-free graphs for all graphs $H$ on 4 vertices. To obtain the complete dichotomy, we prove the finiteness for four new graphs $H$ using various techniques -- such as Ramsey-type arguments and the dual of Dilworth's Theorem -- that may be of independent interest. Full Article
rap The formation of trapped surfaces in the gravitational collapse of spherically symmetric scalar fields with a positive cosmological constant. (arXiv:2005.03434v1 [gr-qc]) By arxiv.org Published On :: Given spherically symmetric characteristic initial data for the Einstein-scalar field system with a positive cosmological constant, we provide a criterion, in terms of the dimensionless size and dimensionless renormalized mass content of an annular region of the data, for the formation of a future trapped surface. This corresponds to an extension of Christodoulou's classical criterion by the inclusion of the cosmological term. Full Article
rap Aspiration can promote cooperation in well-mixed populations as in regular graphs. (arXiv:2005.03421v1 [q-bio.PE]) By arxiv.org Published On :: Classical studies on aspiration-based dynamics suggest that a dissatisfied individual changes strategy without taking into account the success of others. This promotes defection spreading. The imitation-based dynamics allow individuals to imitate successful strategies without taking into account their own-satisfactions. In this article, we propose to study a dynamic based on aspiration which takes into account imitation of successful strategies for dissatisfied individuals. This helps cooperative members to resist. Individuals compare their success to their desired satisfaction level before making a decision to update their strategies. This mechanism helps individuals with a minimum of self-satisfaction to maintain their strategies. If an individual is dissatisfied, it will learn from others by choosing successful strategies. We derive an exact expression of the fixation probability in well-mixed populations as in structured populations in networks. As a result, we show that selection may favor cooperation more than defection in well-mixed populations as in populations ranged over a regular graph. We show that the best scenario is a graph with small connectivity. Full Article
rap A note on Penner's cocycle on the fatgraph complex. (arXiv:2005.03414v1 [math.GT]) By arxiv.org Published On :: We study a 1-cocycle on the fatgraph complex of a punctured surface introduced by Penner. We present an explicit cobounding cochain for this cocycle, whose formula involves a summation over trivalent vertices of a trivalent fatgraph spine. In a similar fashion, we express the symplectic form of the underlying surface of a given fatgraph spine. Full Article
rap Minimum pair degree condition for tight Hamiltonian cycles in $4$-uniform hypergraphs. (arXiv:2005.03391v1 [math.CO]) By arxiv.org Published On :: We show that every 4-uniform hypergraph with $n$ vertices and minimum pair degree at least $(5/9+o(1))n^2/2$ contains a tight Hamiltonian cycle. This degree condition is asymptotically optimal. Full Article
rap Dynamical Phase Transitions for Fluxes of Mass on Finite Graphs. (arXiv:2005.03262v1 [cond-mat.stat-mech]) By arxiv.org Published On :: We study the time-averaged flux in a model of particles that randomly hop on a finite directed graph. In the limit as the number of particles and the time window go to infinity but the graph remains finite, the large-deviation rate functional of the average flux is given by a variational formulation involving paths of the density and flux. We give sufficient conditions under which the large deviations of a given time averaged flux is determined by paths that are constant in time. We then consider a class of models on a discrete ring for which it is possible to show that a better strategy is obtained producing a time-dependent path. This phenomenon, called a dynamical phase transition, is known to occur for some particle systems in the hydrodynamic scaling limit, which is thus extended to the setting of a finite graph. Full Article
rap On the Gorenstein property of the Ehrhart ring of the stable set polytope of an h-perfect graph. (arXiv:2005.03259v1 [math.CO]) By arxiv.org Published On :: In this paper, we give a criterion of the Gorenstein property of the Ehrhart ring of the stable set polytope of an h-perfect graph: the Ehrhart ring of the stable set polytope of an h-perfect graph $G$ is Gorenstein if and only if (1) sizes of maximal cliques are constant (say $n$) and (2) (a) $n=1$, (b) $n=2$ and there is no odd cycle without chord and length at least 7 or (c) $ngeq 3$ and there is no odd cycle without chord and length at least 5. Full Article
rap New constructions of strongly regular Cayley graphs on abelian groups. (arXiv:2005.03183v1 [math.CO]) By arxiv.org Published On :: In this paper, we give new constructions of strongly regular Cayley graphs on abelian groups as generalizations of a series of known constructions: the construction of covering extended building sets in finite fields by Xia (1992), the product construction of Menon-Hadamard difference sets by Turyn (1984), and the construction of Paley type partial difference sets by Polhill (2010). Then, we obtain new large families of strongly regular Cayley graphs of Latin square type or negative Latin square type. Full Article
rap Sharp p-bounds for maximal operators on finite graphs. (arXiv:2005.03146v1 [math.CA]) By arxiv.org Published On :: Let $G=(V,E)$ be a finite graph and $M_G$ be the centered Hardy-Littlewood maximal operator defined there. We found the optimal value $C_{G,p}$ such that the inequality $$Var_{p}(M_{G}f)le C_{G,p}Var_{p}(f)$$ holds for every every $f:V o mathbb{R},$ where $Var_p$ stands for the $p$-variation, when: (i)$G=K_n$ (complete graph) and $pin [frac{ln(4)}{ln(6)},infty)$ or $G=K_4$ and $pin (0,infty)$;(ii) $G=S_n$(star graph) and $1ge pge frac{1}{2}$; $pin (0,frac{1}{2})$ and $nge C(p)<infty$ or $G=S_3$ and $pin (1,infty).$ We also found the optimal value $L_{G,2}$ such that the inequality $$|M_{G}f|_2le L_{G,2}|f|_2$$ holds for every $f:V o mathbb{R}$, when: (i)$G=K_n$ and $nge 3$;(ii)$G=S_n$ and $nge 3.$ Full Article
rap On planar graphs of uniform polynomial growth. (arXiv:2005.03139v1 [math.PR]) By arxiv.org Published On :: Consider an infinite planar graph with uniform polynomial growth of degree d > 2. Many examples of such graphs exhibit similar geometric and spectral properties, and it has been conjectured that this is necessary. We present a family of counterexamples. In particular, we show that for every rational d > 2, there is a planar graph with uniform polynomial growth of degree d on which the random walk is transient, disproving a conjecture of Benjamini (2011). By a well-known theorem of Benjamini and Schramm, such a graph cannot be a unimodular random graph. We also give examples of unimodular random planar graphs of uniform polynomial growth with unexpected properties. For instance, graphs of (almost sure) uniform polynomial growth of every rational degree d > 2 for which the speed exponent of the walk is larger than 1/d, and in which the complements of all balls are connected. This resolves negatively two questions of Benjamini and Papasoglou (2011). Full Article
rap 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
rap Optimal Adjacent Vertex-Distinguishing Edge-Colorings of Circulant Graphs. (arXiv:2004.12822v2 [cs.DM] UPDATED) By arxiv.org Published On :: A k-proper edge-coloring of a graph G is called adjacent vertex-distinguishing if any two adjacent vertices are distinguished by the set of colors appearing in the edges incident to each vertex. The smallest value k for which G admits such coloring is denoted by $chi$'a (G). We prove that $chi$'a (G) = 2R + 1 for most circulant graphs Cn([[1, R]]). Full Article
rap Personal Health Knowledge Graphs for Patients. (arXiv:2004.00071v2 [cs.AI] UPDATED) By arxiv.org Published On :: Existing patient data analytics platforms fail to incorporate information that has context, is personal, and topical to patients. For a recommendation system to give a suitable response to a query or to derive meaningful insights from patient data, it should consider personal information about the patient's health history, including but not limited to their preferences, locations, and life choices that are currently applicable to them. In this review paper, we critique existing literature in this space and also discuss the various research challenges that come with designing, building, and operationalizing a personal health knowledge graph (PHKG) for patients. Full Article
rap Subgraph densities in a surface. (arXiv:2003.13777v2 [math.CO] UPDATED) By arxiv.org Published On :: Given a fixed graph $H$ that embeds in a surface $Sigma$, what is the maximum number of copies of $H$ in an $n$-vertex graph $G$ that embeds in $Sigma$? We show that the answer is $Theta(n^{f(H)})$, where $f(H)$ is a graph invariant called the `flap-number' of $H$, which is independent of $Sigma$. This simultaneously answers two open problems posed by Eppstein (1993). When $H$ is a complete graph we give more precise answers. Full Article
rap Eccentricity terrain of $delta$-hyperbolic graphs. (arXiv:2002.08495v2 [cs.DM] UPDATED) By arxiv.org Published On :: A graph $G=(V,E)$ is $delta$-hyperbolic if for any four vertices $u,v,w,x$, the two larger of the three distance sums $d(u,v)+d(w,x)$, $d(u,w)+d(v,x)$, and $d(u,x)+d(v,w)$ differ by at most $2delta geq 0$. Recent work shows that many real-world graphs have small hyperbolicity $delta$. This paper describes the eccentricity terrain of a $delta$-hyperbolic graph. The eccentricity function $e_G(v)=max{d(v,u) : u in V}$ partitions the vertex set of $G$ into eccentricity layers $C_{k}(G) = {v in V : e(v)=rad(G)+k}$, $k in mathbb{N}$, where $rad(G)=min{e_G(v): vin V}$ is the radius of $G$. The paper studies the eccentricity layers of vertices along shortest paths, identifying such terrain features as hills, plains, valleys, terraces, and plateaus. It introduces the notion of $eta$-pseudoconvexity, which implies Gromov's $epsilon$-quasiconvexity, and illustrates the abundance of pseudoconvex sets in $delta$-hyperbolic graphs. In particular, it shows that all sets $C_{leq k}(G)={vin V : e_G(v) leq rad(G) + k}$, $kin mathbb{N}$, are $(2delta-1)$-pseudoconvex. Additionally, several bounds on the eccentricity of a vertex are obtained which yield a few approaches to efficiently approximating all eccentricities. An $O(delta |E|)$ time eccentricity approximation $hat{e}(v)$, for all $vin V$, is presented that uses distances to two mutually distant vertices and satisfies $e_G(v)-2delta leq hat{e}(v) leq {e_G}(v)$. It also shows existence of two eccentricity approximating spanning trees $T$, one constructible in $O(delta |E|)$ time and the other in $O(|E|)$ time, which satisfy ${e}_G(v) leq e_T(v) leq {e}_G(v)+4delta+1$ and ${e}_G(v) leq e_T(v) leq {e}_G(v)+6delta$, respectively. Thus, the eccentricity terrain of a tree gives a good approximation (up-to an additive error $O(delta))$ of the eccentricity terrain of a $delta$-hyperbolic graph. Full Article
rap Measuring Social Bias in Knowledge Graph Embeddings. (arXiv:1912.02761v2 [cs.CL] UPDATED) By arxiv.org Published On :: It has recently been shown that word embeddings encode social biases, with a harmful impact on downstream tasks. However, to this point there has been no similar work done in the field of graph embeddings. We present the first study on social bias in knowledge graph embeddings, and propose a new metric suitable for measuring such bias. We conduct experiments on Wikidata and Freebase, and show that, as with word embeddings, harmful social biases related to professions are encoded in the embeddings with respect to gender, religion, ethnicity and nationality. For example, graph embeddings encode the information that men are more likely to be bankers, and women more likely to be homekeepers. As graph embeddings become increasingly utilized, we suggest that it is important the existence of such biases are understood and steps taken to mitigate their impact. Full Article
rap GeoLogic -- Graphical interactive theorem prover for Euclidean geometry. (arXiv:2005.03586v1 [cs.LO]) By arxiv.org Published On :: Domain of mathematical logic in computers is dominated by automated theorem provers (ATP) and interactive theorem provers (ITP). Both of these are hard to access by AI from the human-imitation approach: ATPs often use human-unfriendly logical foundations while ITPs are meant for formalizing existing proofs rather than problem solving. We aim to create a simple human-friendly logical system for mathematical problem solving. We picked the case study of Euclidean geometry as it can be easily visualized, has simple logic, and yet potentially offers many high-school problems of various difficulty levels. To make the environment user friendly, we abandoned strict logic required by ITPs, allowing to infer topological facts from pictures. We present our system for Euclidean geometry, together with a graphical application GeoLogic, similar to GeoGebra, which allows users to interactively study and prove properties about the geometrical setup. Full Article
rap Faceted Search of Heterogeneous Geographic Information for Dynamic Map Projection. (arXiv:2005.03531v1 [cs.HC]) By arxiv.org Published On :: This paper proposes a faceted information exploration model that supports coarse-grained and fine-grained focusing of geographic maps by offering a graphical representation of data attributes within interactive widgets. The proposed approach enables (i) a multi-category projection of long-lasting geographic maps, based on the proposal of efficient facets for data exploration in sparse and noisy datasets, and (ii) an interactive representation of the search context based on widgets that support data visualization, faceted exploration, category-based information hiding and transparency of results at the same time. The integration of our model with a semantic representation of geographical knowledge supports the exploration of information retrieved from heterogeneous data sources, such as Public Open Data and OpenStreetMap. We evaluated our model with users in the OnToMap collaborative Web GIS. The experimental results show that, when working on geographic maps populated with multiple data categories, it outperforms simple category-based map projection and traditional faceted search tools, such as checkboxes, in both user performance and experience. Full Article
rap Linear Time LexDFS on Chordal Graphs. (arXiv:2005.03523v1 [cs.DM]) By arxiv.org Published On :: Lexicographic Depth First Search (LexDFS) is a special variant of a Depth First Search (DFS), which was introduced by Corneil and Krueger in 2008. While this search has been used in various applications, in contrast to other graph searches, no general linear time implementation is known to date. In 2014, K"ohler and Mouatadid achieved linear running time to compute some special LexDFS orders for cocomparability graphs. In this paper, we present a linear time implementation of LexDFS for chordal graphs. Our algorithm is able to find any LexDFS order for this graph class. To the best of our knowledge this is the first unrestricted linear time implementation of LexDFS on a non-trivial graph class. In the algorithm we use a search tree computed by Lexicographic Breadth First Search (LexBFS). Full Article
rap Anonymized GCN: A Novel Robust Graph Embedding Method via Hiding Node Position in Noise. (arXiv:2005.03482v1 [cs.LG]) By arxiv.org Published On :: Graph convolution network (GCN) have achieved state-of-the-art performance in the task of node prediction in the graph structure. However, with the gradual various of graph attack methods, there are lack of research on the robustness of GCN. At this paper, we will design a robust GCN method for node prediction tasks. Considering the graph structure contains two types of information: node information and connection information, and attackers usually modify the connection information to complete the interference with the prediction results of the node, we first proposed a method to hide the connection information in the generator, named Anonymized GCN (AN-GCN). By hiding the connection information in the graph structure in the generator through adversarial training, the accurate node prediction can be completed only by the node number rather than its specific position in the graph. Specifically, we first demonstrated the key to determine the embedding of a specific node: the row corresponding to the node of the eigenmatrix of the Laplace matrix, by target it as the output of the generator, we designed a method to hide the node number in the noise. Take the corresponding noise as input, we will obtain the connection structure of the node instead of directly obtaining. Then the encoder and decoder are spliced both in discriminator, so that after adversarial training, the generator and discriminator can cooperate to complete the encoding and decoding of the graph, then complete the node prediction. Finally, All node positions can generated by noise at the same time, that is to say, the generator will hides all the connection information of the graph structure. The evaluation shows that we only need to obtain the initial features and node numbers of the nodes to complete the node prediction, and the accuracy did not decrease, but increased by 0.0293. Full Article
rap Bundle Recommendation with Graph Convolutional Networks. (arXiv:2005.03475v1 [cs.IR]) By arxiv.org Published On :: Bundle recommendation aims to recommend a bundle of items for a user to consume as a whole. Existing solutions integrate user-item interaction modeling into bundle recommendation by sharing model parameters or learning in a multi-task manner, which cannot explicitly model the affiliation between items and bundles, and fail to explore the decision-making when a user chooses bundles. In this work, we propose a graph neural network model named BGCN (short for extit{ extBF{B}undle extBF{G}raph extBF{C}onvolutional extBF{N}etwork}) for bundle recommendation. BGCN unifies user-item interaction, user-bundle interaction and bundle-item affiliation into a heterogeneous graph. With item nodes as the bridge, graph convolutional propagation between user and bundle nodes makes the learned representations capture the item level semantics. Through training based on hard-negative sampler, the user's fine-grained preferences for similar bundles are further distinguished. Empirical results on two real-world datasets demonstrate the strong performance gains of BGCN, which outperforms the state-of-the-art baselines by 10.77\% to 23.18\%. Full Article
rap Estimating Blood Pressure from Photoplethysmogram Signal and Demographic Features using Machine Learning Techniques. (arXiv:2005.03357v1 [eess.SP]) By arxiv.org Published On :: Hypertension is a potentially unsafe health ailment, which can be indicated directly from the Blood pressure (BP). Hypertension always leads to other health complications. Continuous monitoring of BP is very important; however, cuff-based BP measurements are discrete and uncomfortable to the user. To address this need, a cuff-less, continuous and a non-invasive BP measurement system is proposed using Photoplethysmogram (PPG) signal and demographic features using machine learning (ML) algorithms. PPG signals were acquired from 219 subjects, which undergo pre-processing and feature extraction steps. Time, frequency and time-frequency domain features were extracted from the PPG and their derivative signals. Feature selection techniques were used to reduce the computational complexity and to decrease the chance of over-fitting the ML algorithms. The features were then used to train and evaluate ML algorithms. The best regression models were selected for Systolic BP (SBP) and Diastolic BP (DBP) estimation individually. Gaussian Process Regression (GPR) along with ReliefF feature selection algorithm outperforms other algorithms in estimating SBP and DBP with a root-mean-square error (RMSE) of 6.74 and 3.59 respectively. This ML model can be implemented in hardware systems to continuously monitor BP and avoid any critical health conditions due to sudden changes. Full Article
rap Interval type-2 fuzzy logic system based similarity evaluation for image steganography. (arXiv:2005.03310v1 [cs.MM]) By arxiv.org Published On :: Similarity measure, also called information measure, is a concept used to distinguish different objects. It has been studied from different contexts by employing mathematical, psychological, and fuzzy approaches. Image steganography is the art of hiding secret data into an image in such a way that it cannot be detected by an intruder. In image steganography, hiding secret data in the plain or non-edge regions of the image is significant due to the high similarity and redundancy of the pixels in their neighborhood. However, the similarity measure of the neighboring pixels, i.e., their proximity in color space, is perceptual rather than mathematical. This paper proposes an interval type 2 fuzzy logic system (IT2 FLS) to determine the similarity between the neighboring pixels by involving an instinctive human perception through a rule-based approach. The pixels of the image having high similarity values, calculated using the proposed IT2 FLS similarity measure, are selected for embedding via the least significant bit (LSB) method. We term the proposed procedure of steganography as IT2 FLS LSB method. Moreover, we have developed two more methods, namely, type 1 fuzzy logic system based least significant bits (T1FLS LSB) and Euclidean distance based similarity measures for least significant bit (SM LSB) steganographic methods. Experimental simulations were conducted for a collection of images and quality index metrics, such as PSNR, UQI, and SSIM are used. All the three steganographic methods are applied on datasets and the quality metrics are calculated. The obtained stego images and results are shown and thoroughly compared to determine the efficacy of the IT2 FLS LSB method. Finally, we have done a comparative analysis of the proposed approach with the existing well-known steganographic methods to show the effectiveness of our proposed steganographic method. Full Article
rap Exploratory Analysis of Covid-19 Tweets using Topic Modeling, UMAP, and DiGraphs. (arXiv:2005.03082v1 [cs.SI]) By arxiv.org Published On :: This paper illustrates five different techniques to assess the distinctiveness of topics, key terms and features, speed of information dissemination, and network behaviors for Covid19 tweets. First, we use pattern matching and second, topic modeling through Latent Dirichlet Allocation (LDA) to generate twenty different topics that discuss case spread, healthcare workers, and personal protective equipment (PPE). One topic specific to U.S. cases would start to uptick immediately after live White House Coronavirus Task Force briefings, implying that many Twitter users are paying attention to government announcements. We contribute machine learning methods not previously reported in the Covid19 Twitter literature. This includes our third method, Uniform Manifold Approximation and Projection (UMAP), that identifies unique clustering-behavior of distinct topics to improve our understanding of important themes in the corpus and help assess the quality of generated topics. Fourth, we calculated retweeting times to understand how fast information about Covid19 propagates on Twitter. Our analysis indicates that the median retweeting time of Covid19 for a sample corpus in March 2020 was 2.87 hours, approximately 50 minutes faster than repostings from Chinese social media about H7N9 in March 2013. Lastly, we sought to understand retweet cascades, by visualizing the connections of users over time from fast to slow retweeting. As the time to retweet increases, the density of connections also increase where in our sample, we found distinct users dominating the attention of Covid19 retweeters. One of the simplest highlights of this analysis is that early-stage descriptive methods like regular expressions can successfully identify high-level themes which were consistently verified as important through every subsequent analysis. Full Article
rap Evaluating text coherence based on the graph of the consistency of phrases to identify symptoms of schizophrenia. (arXiv:2005.03008v1 [cs.CL]) By arxiv.org Published On :: Different state-of-the-art methods of the detection of schizophrenia symptoms based on the estimation of text coherence have been analyzed. The analysis of a text at the level of phrases has been suggested. The method based on the graph of the consistency of phrases has been proposed to evaluate the semantic coherence and the cohesion of a text. The semantic coherence, cohesion, and other linguistic features (lexical diversity, lexical density) have been taken into account to form feature vectors for the training of a model-classifier. The training of the classifier has been performed on the set of English-language interviews. According to the retrieved results, the impact of each feature on the output of the model has been analyzed. The results obtained can indicate that the proposed method based on the graph of the consistency of phrases may be used in the different tasks of the detection of mental illness. Full Article
rap 24 Must-Know Graphic Design Terms By feedproxy.google.com Published On :: Thu, 19 Sep 2019 13:31:41 +0000 Graphic design is everywhere — it’s used in traditional marketing efforts like billboards and fliers, and more importantly, it’s used in nearly every single digital marketing initiative from web design to social media marketing. If you’re a business that’s working with a digital marketing agency for any number of marketing campaigns (especially web design), it’s […] The post 24 Must-Know Graphic Design Terms appeared first on WebFX Blog. Full Article Web Design
rap Psychology of Color [Infographic] By feedproxy.google.com Published On :: Mon, 09 Mar 2020 13:44:45 +0000 Perhaps no choice is as vital to marketing as color. Whether you are selecting the color for a product or for your email marketing campaign, color has a tremendous impact on all of us. Subconsciously, we associate different colors with different things. This infographic examines the psychology of color and looks at some common associations […] The post Psychology of Color [Infographic] appeared first on WebFX Blog. Full Article Web Design
rap Use Of Ngx-Bootstrap Typehead In Angular 8 By dzone.com Published On :: Thu, 07 May 2020 14:10:19 GMT Introduction Ngx-Bootstrap has released a package of open-source tools which are native Angular directives for Bootstrap 3 and 4. It contains all core components powered by Angular. In this article, we will learn about the Typehead component which is a cool feature of Ngx-bootstrap. What Is Typeahead? Typeahead — Also known as autocomplete or autosuggest is a language prediction tool that many search interfaces use to provide suggestions for users as they type in a textbox. This is a method for searching and filtering through text. It is also sometimes known as autocomplete, incremental search, search-as-you-type, and inline search. Full Article tutorial web dev angular angular 8 typeahead
rap Graphene prepared by using edge functionalization of graphite By www.freepatentsonline.com Published On :: Tue, 28 Apr 2015 08:00:00 EDT Disclosed is a method for producing graphene functionalized at its edge positions of graphite. Organic material having one or more functional groups is reacted with graphite in reaction medium comprising methanesulfonic acid and phosphorus pentoxide, or in reaction medium comprising trifluoromethanesulfonic acid, to produce graphene having organic material fuctionalized at edges. And then, high purity and large scaled graphene and film can be obtained by dispersing, centrifugal separating the functionalized graphene in a solvent and reducing, in particular heat treating the graphene. According to the present invention graphene can be produced inexpensively in a large amount with a minimum loss of graphite. (FIG. 1) Full Article
rap Therapeutic compounds By www.freepatentsonline.com Published On :: Tue, 05 May 2015 08:00:00 EDT The invention relates to protein binding interacting/binding compounds and methods of identifying and using them. The invention further relates to pharmaceutical compositions and methods for treating 5-HT2C and/or RSK disorders, including diseases and disorders mediated by GPCRs and/or RSKs. Full Article
rap Wearable electromyography-based human-computer interface By www.freepatentsonline.com Published On :: Tue, 19 May 2015 08:00:00 EDT A “Wearable Electromyography-Based Controller” includes a plurality of Electromyography (EMG) sensors and provides a wired or wireless human-computer interface (HCI) for interacting with computing systems and attached devices via electrical signals generated by specific movement of the user's muscles. Following initial automated self-calibration and positional localization processes, measurement and interpretation of muscle generated electrical signals is accomplished by sampling signals from the EMG sensors of the Wearable Electromyography-Based Controller. In operation, the Wearable Electromyography-Based Controller is donned by the user and placed into a coarsely approximate position on the surface of the user's skin. Automated cues or instructions are then provided to the user for fine-tuning placement of the Wearable Electromyography-Based Controller. Examples of Wearable Electromyography-Based Controllers include articles of manufacture, such as an armband, wristwatch, or article of clothing having a plurality of integrated EMG-based sensor nodes and associated electronics. Full Article
rap Therapeutic dental composition and related methods By www.freepatentsonline.com Published On :: Tue, 03 Mar 2015 08:00:00 EST Dental compositions are provided comprising a compound of Formula (I) or a pharmaceutically acceptable salt thereof: wherein n is an integer from about 2 to about 5. Full Article
rap 5-(pyridin-2-yl-amino)-pyrazine-2-carbonitrile compounds and their therapeutic use By www.freepatentsonline.com Published On :: Tue, 26 May 2015 08:00:00 EDT The present invention pertains generally to the field of therapeutic compounds. More specifically the present invention pertains to certain pyridyl-amino-pyrazine carbonitrile compounds that, inter alia, inhibit Checkpoint Kinase 1 (CHK1) kinase function. The present invention also pertains to pharmaceutical compositions comprising such compounds, and the use of such compounds and compositions, both in vitro and in vivo, to inhibit CHK1 kinase function, and in the treatment of diseases and conditions that are mediated by CHK1, that are ameliorated by the inhibition of CHK1 kinase function, etc., including proliferative conditions such as cancer, etc., optionally in combination with another agent, for example, (a) a DNA topoisomerase I or II inhibitor; (b) a DNA damaging agent; (c) an antimetabolite or thymidylate synthase (TS) inhibitor; (d) a microtubule targeted agent; and (e) ionizing radiation. Full Article
rap Controlled synthesis of monolithically-integrated graphene structure By www.freepatentsonline.com Published On :: Tue, 12 May 2015 08:00:00 EDT In a method for fabricating a graphene structure, there is formed on a fabrication substrate a pattern of a plurality of distinct graphene catalyst materials. In one graphene synthesis step, different numbers of graphene layers are formed on the catalyst materials in the formed pattern. In a method for fabricating a graphene transistor, on a fabrication substrate at least one graphene catalyst material is provided at a substrate region specified for synthesizing a graphene transistor channel and at least one graphene catalyst material is provided at a substrate region specified for synthesizing a graphene transistor source, and at a substrate region specified for synthesizing a graphene transistor drain. Then in one graphene synthesis step, at least one layer of graphene is formed at the substrate region for the graphene transistor channel, and at the regions for the transistor source and drain there are formed a plurality of layers of graphene. Full Article
rap Non-volatile memory structure containing nanodots and continuous metal layer charge traps and method of making thereof By www.freepatentsonline.com Published On :: Tue, 12 May 2015 08:00:00 EDT A memory device includes a semiconductor channel, a tunnel dielectric layer located over the semiconductor channel, a first charge trap including a plurality of electrically conductive nanodots located over the tunnel dielectric layer, dielectric separation layer located over the nanodots, a second charge trap including a continuous metal layer located over the separation layer, a blocking dielectric located over the second charge trap, and a control gate located over the blocking dielectric. Full Article
rap Functional fabric based test wrapper for circuit testing of IP blocks By www.freepatentsonline.com Published On :: Tue, 26 May 2015 08:00:00 EDT A Test Wrapper and associated Test Access Mechanism (TAM) architecture for facilitating testing of IP blocks integrated on a System on a Chip (SoC). The TAM architecture includes a Test Controller and one or more Test Wrappers that are integrated on the SoC proximate to IP blocks. Test data and commands corresponding to input from an external tester are packaged by the Test Controller and sent to one or more Test Wrappers via an interconnect fabric. The Test Wrappers interface with one or more IP test ports to provide test data, control, and/or stimulus signals to the IP blocks to facilitate circuit-level testing of the IP blocks. Test results for the circuit-level tests are returned to the Test Controller via the fabric. Test Wrappers may be configured to pass through interconnect signals, enabling functional testing of IP blocks to be facilitated via test packages and test results transmitted between the Test Controller and the IP blocks via the fabric. Test wrappers may also be configured to test multiple IP blocks comprising a test partition. Full Article
rap Ceramic ingot of spent filter having trapped radioactive cesium and method of preparing the same By www.freepatentsonline.com Published On :: Tue, 03 Mar 2015 08:00:00 EST A method of preparing a simple ceramic ingot of a spent filter having radioactive cesium trapped therein, and a ceramic ingot of a spent filter having improved properties such as leach resistance, thermal stability, and cesium content are provided. The method includes grinding and mixing a spent filter having cesium trapped therein, adding a solidifying agent, and sintering the spent filter. The method of preparing a ceramic ingot of a spent filter can be useful in preparing the ceramic ingot of the spent filter from only the spent filter by means of simple grinding and sintering, and in preparing the ceramic ingot of the spent filter by adding a small amount of a solidifying agent. The ceramic ingot of the spent filter has a high density and improved thermal stability, and shows improved leach resistance since a leach rate of a radioactive material is remarkably low. Therefore, the spent filter having radioactive cesium trapped therein can be effectively used to prepare a stable ceramic ingot. Full Article
rap Method and apparatus for a geographically determined Jewish religious clock and electrical device combination with holiday and preference modes By www.freepatentsonline.com Published On :: Tue, 05 May 2015 08:00:00 EDT An independently functioning or centrally controlled wall light switch is configured to operate in normal mode and a Jewish holiday mode wherein the state of the light is fixed, regardless of the user's physical manipulation of the light switch. The control system automatically activates holiday mode by combining a geographically determined Jewish religious clock executed by software and hardware that utilizes the current time, date and geographical location of the apparatus in accordance with the Jewish definition of time and laws for calculating numerous religiously significant shifting daily points in time. The control system further incorporates several energy saving and preference modes by utilizing a particular day's calculated religious points in time in conjunction with holiday behavior patterns common to most Jewish families to provide the user with a greatly simplified means of programming an automatically adjusting on/off light timer and dimming overlay functionality during holiday mode. Full Article
rap System and method for below-operating system trapping and securing loading of code into memory By www.freepatentsonline.com Published On :: Tue, 19 May 2015 08:00:00 EDT A system for protecting an electronic device against malware includes a memory, an operating system configured to execute on the electronic device, and a below-operating-system security agent. The below-operating-system security agent is configured to trap an attempted access of a resource of the electronic device, access one or more security rules to determine whether the attempted access is indicative of malware, and operate at a level below all of the operating systems of the electronic device accessing the memory. The attempted access includes attempting to write instructions to the memory and attempting to execute the instructions. Full Article
rap Fluorographene and preparation method thereof By www.freepatentsonline.com Published On :: Tue, 17 Mar 2015 08:00:00 EDT A fluorographene and preparation method thereof are provided. For the said fluorographene, the fraction of F is 0.5 Full Article
rap Foams of graphene, method of making and materials made thereof By www.freepatentsonline.com Published On :: Tue, 21 Apr 2015 08:00:00 EDT Method for making a liquid foam from graphene. The method includes preparing an aqueous dispersion of graphene oxide and adding a water miscible compound to the aqueous dispersion to produce a mixture including a modified form of graphene oxide. A second immiscible fluid (a gas or a liquid) with or without a surfactant are added to the mixture and agitated to form a fluid/water composite wherein the modified form of graphene oxide aggregates at the interfaces between the fluid and water to form either a closed or open cell foam. The modified form of graphene oxide is the foaming agent. Full Article
rap Applying coding standards in graphical programming environments By www.freepatentsonline.com Published On :: Tue, 26 May 2015 08:00:00 EDT Graphical programming or modeling environments in which a coding standard can be applied to graphical programs or models are disclosed. The present invention provides mechanisms for applying the coding standard to graphical programs/models in the graphical programming/modeling environments. The mechanisms may detect violations of the coding standard in the graphical model and report such violations to the users. The mechanisms may automatically correct the graphical model to remove the violations from the graphical model. The mechanisms may also automatically avoid the violations in the simulation and/or code generation of the graphical model. Full Article
rap Method and system for forming patterns with charged particle beam lithography By www.freepatentsonline.com Published On :: Tue, 19 May 2015 08:00:00 EDT In a method for fracturing or mask data preparation or mask process correction for charged particle beam lithography, a plurality of shots are determined that will form a pattern on a surface, where shots are determined so as to reduce sensitivity of the resulting pattern to changes in beam blur (βf). In some embodiments, the sensitivity to changes in βf is reduced by varying the charged particle surface dosage for a portion of the pattern. Methods for forming patterns on a surface, and for manufacturing an integrated circuit are also disclosed, in which pattern sensitivity to changes in βf is reduced. Full Article
rap Method and system for critical dimension uniformity using charged particle beam lithography By www.freepatentsonline.com Published On :: Tue, 19 May 2015 08:00:00 EDT A method for mask data preparation or mask process correction is disclosed in which a set of charged particle beam shots is determined which is capable of forming a pattern on a surface, wherein critical dimension uniformity (CDU) of the pattern is optimized. In some embodiments the CDU is optimized by varying at least two factors. In other embodiments, model-based techniques are used. In yet other embodiments, the surface is a reticle to be used in an optical lithographic process to form a pattern on a wafer, and CDU on the wafer is optimized. Full Article
rap Method and system for forming high accuracy patterns using charged particle beam lithography By www.freepatentsonline.com Published On :: Tue, 26 May 2015 08:00:00 EDT A method and system for optical proximity correction (OPC) is disclosed in which a set of shaped beam shots is determined which, when used in a shaped beam charged particle beam writer, will form a pattern on a reticle, where some of the shots overlap, where the pattern on the reticle is an OPC-corrected version of an input pattern, and where the sensitivity of the pattern on the reticle to manufacturing variation is reduced. A method for fracturing or mask data preparation is also disclosed. Full Article
rap Methods and apparatus to create process control graphics based on process control information By www.freepatentsonline.com Published On :: Tue, 26 May 2015 08:00:00 EDT Methods and apparatus to automatically link process control graphics to process control algorithm information are described. An example method involves displaying a first process control image including process control algorithm information and displaying adjacent to the first process control image a second process control image to include process control graphics. The method automatically links at least some of the process control algorithm information to a graphic in the second process control image in response to user inputs associated with the first and second process control images. Full Article
rap Graphical display for sorting and filtering a list in a space-constrained view By www.freepatentsonline.com Published On :: Tue, 26 May 2015 08:00:00 EDT Techniques for sorting and filtering a list in a space-constrained viewing area are described. A filter widget and a list of items are displayed in a view of an electronic display screen. In response to user input selecting the filter widget, and without changing to a different view, a filter category overlay is displayed in the view to provide various selectable filter categories. In response to selection of a filter category, a visual depiction of the selected filter category is displayed in the view. The list of items is filtered according to the selected filter category and displayed in the view without changing to any other view. Subsequently added visual depictions are linearly stacked in the view. Further, a filter modification overlay, which provides selectable filtering attributes, is displayed upon selection of a visual depiction. Full Article