A method for computer-aided closed and/or open-loop control of a technical system is provided. A first value of an output quantity is predicted on a data-based model at a current point in time. A second value of the output quantity is determined from an analytical model. The state of the technical system at the current point is assigned a confidence score in the correctness of prediction of the data-based model. A third value of the output quantity is determined from the first and second value as a function of the confidence score for controlling the technical system. A suitable value for the output quantity can be derived from the analytical model even for regions of the technical system in which the quality of prediction of the data-based model is low because of a small set of training data. The technical systems can be turbines, such as gas turbines.

Disclosed herein are methods, compositions and tools for repairing articular surfaces repair materials and for repairing an articular surface. The articular surface repairs are customizable or highly selectable by patient and geared toward providing optimal fit and function. The surgical tools are designed to be customizable or highly selectable by patient to increase the speed, accuracy and simplicity of performing total or partial arthroplasty.

Vacuum deposited thin films of material are described to create an interface that non-preferentially interacts with different domains of an underlying block copolymer film. The non-preferential interface prevents formation of a wetting layer and influences the orientation of domains in the block copolymer. The purpose of the deposited polymer is to produce nanostructured features in a block copolymer film that can serve as lithographic patterns.

Provided are methods of depositing polymer solutions on substrates to form various optical elements. A polymer solution may include about 0.1%-30% by weight of a specific polymer having rigid rod-like molecules. The molecules may include various cores, spacers, and sides groups to ensure their solubility, viscosity, and cross-linking ability. The deposition techniques may include slot die, spray, molding, roll coating, and so forth. Pre-deposition techniques may be used to improve wettability and adhesion of substrates. Post-deposition techniques may include ultraviolet cross-linking, specific drying techniques, evaporation of solvent, treating with salt solutions, and shaping. The disclosed polymers and deposition processes may yield optical elements with high refractive index values, such as greater than 1.6. These optical elements may be used as +A plates, −C plates, or biaxial polymers and used as retarders in LCD active panels or as light collimators and light guides.

An intracorporeal autonomous active medical device having a capsule body and a base. The capsule body includes a body portion and a lid portion, and the capsule body contains therein electronic circuitry containing the active elements of the autonomous medical device, and a power supply. The capsule body also includes a fastening system on an exterior surface of the capsule body that is configured to correspond with a fastening mechanism on the base configured to be anchored to a tissue wall. The fastening mechanism provides selective engagement between the capsule body and the base.

An implantable medical device (IMD) can include a cardiac pacemaker or an implantable cardioverter-defibrillator (ICD). Various portions of the IMD, such as a device body, a lead body, or a lead tip, can be provided to reduce or dissipate a current and heat induced by various external environmental factors. According to various embodiments, features can be incorporated into the lead body, the lead tip, or the IMD body to reduce the creation of an induced current, or dissipate the induced Current and heat created due to an induced current in the lead. For example, an IMD can include at least one outer conductive member and a first electrode. The first electrode can be in electrical communication with the at least one outer conductive member. The first electrode can dissipate a current induced in the at least one outer conductive member via a first portion of the anatomical structure.

Embodiments of the present invention include an apparatus and method for treatment of pain by a device that provides transcutaneous electrical nerve stimulation. The device includes an applicator equipped with an electric pulse provider that sends an electric pulse to a set of electrodes disposed in an applicator head. The device is placed onto the skin of a patient's body at the point where the patient experiences pain and such that the electrodes of the device contact the skin of the patient while an insulating land area between the electrodes compresses the nerve during transmittal of the electric pulse through the electrodes and into the patient's body.

It is critical in an inductively link medical implant, such as a visual prosthesis or other neural stimulator, to adjust the external coil to a location to maximize communication between the external coil and internal coil. Converting the signal strength between the coils to a signal easily discernible by a clinician, preferably an audible tone, facilitates the adjustment of the external coil to a preferred location.

Implantable devices and related systems utilize power management features in conjunction with a recharge circuit that includes a coil and capacitance. The reactance such as the capacitance and/or inductance may be variable such that in the event of an overcharge condition, the reactance may be varied to change the resonant frequency of the circuit of the coil from the recharge frequency to another frequency to reduce the power being received. Other power management features may additionally or alternatively be employed. For instance, the device may send an uplink telemetry signal to an external device to request that recharge power be decreased. The device may switch additional resistance into the circuit of the coil to reduce the Q of the circuit. As another example, the device may clamp the circuit of the coil to ground.

A medical device, comprising first and second components coupled via a first wireless link; and a third component coupled to the first device via a second wireless link. The device implements a communication scheme in which transmissions via the second wireless link occur during a time period that is interleaved between periods including transmissions via the first link.

An improved implantable pulse generator (IPG) containing improved telemetry circuitry is disclosed. The IPG includes charging and telemetry coils within the IPG case, which increases their mutual inductance and potential to interfere with each other; particularly problematic is interference to the telemetry coil caused by the charging coil. To combat this, improved telemetry circuitry includes decoupling circuitry for decoupling the charging coil during periods of telemetry between the IPG and an external controller. Such decoupling circuitry can comprise use of pre-existing LSK circuitry during telemetry, or new discrete circuitry dedicated to decoupling. The decoupling circuitry is designed to prevent or at least reduce induced current flowing through the charging coil during data telemetry. The decoupling circuitry can be controlled by the microcontroller in the IPG, or can automatically decouple the charging coil at appropriate times to mitigate an induced current without instruction from the microcontroller.

An electrode system includes an implantable flexible electrode, especially an epidural electrode, having at least one distal electrical contact (12). The electrode includes a subcutaneously implantable port (26), a probe that can be introduced into the port (26) forms part of the electrode system with at least one probe contact (53), and at least one electrical contact element (56) connected to the distal contact (12) is arranged in the port (26) in order to generate an electrical connection with the probe contact (53).

A hermetic terminal for an active implantable medical device (AIMD), includes an RF distance telemetry pin antenna, a capacitor conductively coupled between the antenna and a ground for the AIMD, and an inductor electrically disposed in parallel with the capacitor and conductively coupled between the antenna and a ground for the AIMD. The capacitor and the inductor form a band pass filter for attenuating electromagnetic signals through the antenna except at a selected frequency band. Values of capacitance and inductance are selected such that the band pass filter is resonant at the selected frequency band. In an alternative form, the band pass filter is coupled in series with the telemetry pin antenna for attenuating MRI signals of a selected frequency band.

A lead for providing electrical stimulation of patient tissue includes a distal lead element, at least two proximal lead elements, and a junction coupling the distal lead element to each of the at least two proximal lead elements. The distal lead element includes a plurality of electrodes and a plurality of conductive wires coupled to the plurality of electrodes and extending along a longitudinal axis of the distal lead element. Each of the at least two proximal lead elements includes a plurality of terminals and a plurality of conductive wires coupled to the plurality of terminals and extending along a longitudinal axis of the proximal lead element. The junction includes a circuit arrangement electrically coupling each of the conductive wires of the distal lead element to at least one of the conductive wires of at least one of the at least two proximal lead elements.

An ultrasound medical treatment system includes an end effector insertable into a patient. The end effector includes a tissue-retaining device. The tissue-retaining device includes a first tissue-retaining member having an ultrasound medical-treatment transducer and includes a second tissue-retaining member. The first and second tissue-retaining members are operatively connected together to retain patient tissue between the first and second tissue-retaining members and to release patient tissue so retained. In one example, the second tissue-retaining member has an ultrasound reflector. In the same or a different example, the ultrasound medical-treatment transducer is an ultrasound imaging and medical-treatment transducer.

Embodiments of the present concept are directed to medical devices having features that prevent contaminants from infiltrating the housing of the device while providing a mechanism to provide clear auditory sounds to aid a rescuer in providing care to a patient. In one example, a medical device includes a housing having a transmission area associated with an enclosed voice coil. An exterior diaphragm formed integrally with the housing surrounds the transmission area and provides a watertight seal of the transmission area. In addition, the diaphragm is structured to generate a sound that can be heard by the rescuer from the voice coil.

A combustion device (1) for a gas turbine includes portions (12) having an inner and an outer wall (13, 14) with an interposed noise absorption plate (15) having a plurality of holes (16). The combustion device (1) further has first passages (17) connecting zones between the inner wall (13) and the plate (15) to the inside of the combustion device (1) and second passages (21) for cooling the inner wall (13). The portions (12) also have an inner layer (22) between the inner wall (13) and the plate (15) defining inner chambers (23), each connected to at least a first passage (17), and an outer layer (24) between the outer wall (14) and the plate (15) defining outer chambers (25) connected to the inner chambers (23) via the holes (16) of the plate (15).

The disclosure provides an apparatus and method utilizing fuel reactor comprised of a fuel section, an oxygen carrier section, and a porous divider separating the fuel section and the oxygen carrier section. The porous divider allows fluid communication between the fuel section and the oxygen carrier section while preventing the migration of solids of a particular size. Maintaining particle segregation between the oxygen carrier section and the fuel section during solid fuel gasification and combustion processes allows gases generated in either section to participate in necessary reactions while greatly mitigating issues associated with mixture of the oxygen carrier with char or ash products. The apparatus and method may be utilized with an oxygen uncoupling oxygen carrier such as CuO, Mn3O4, or Co3O4, or utilized with a CO/H2 reducing oxygen carrier such as Fe2O3.

A photoresist composition. The composition has the following: (a) one or more resin binders that include one or more acid sensitive groups and that are substantially free of phenolic groups protected by acetal or ketal groups; (b) one or more photo acid generators, that, upon exposure to a source of high energy, decompose and generate a photoacid strong enough to remove the one or more acid sensitive groups; (c) one or more ionic non-photosensitive additives including an iminium salt; and (d) one or more solvents. There is also a process for patterning relief structures on a substrate employing the photoresist composition.

A resin composition for forming an optical waveguide brings together excellent bending resistance, a low refractive index, and low tackiness suitable for a roll-to-roll (R-to-R) process as a material for forming an optical waveguide, in particular, a material for forming a clad layer. The resin composition for forming an optical waveguide to be used in formation of an optical waveguide includes a polyvinyl acetal compound having a structural unit represented by the following general formula (1) as a main component: in the formula (1), R represents an alkyl group having 1 to 3 carbon atoms, and k, m, and n represent ratios of respective repeating units in a main chain and each represent an integer of 1 or more.

For reading the frets of a stringed electronic musical instrument, a plurality of resistance wire strings are secured to a nut end and a bridge of the instrument, with the strings superposing in parallel relationship over a plurality of conducting frets mounted on a fingerboard on the instrument. The voltages produced by depressing the strings to the conducting frets, after being inverted and linearized, are quantized to levels representative of the particular frets to obviate the effects of contact resistance, and decision voltage levels are selected so as to account for such contact resistance. To enable the signals to be fed as conventional information through a MIDI channel to a synthesizer for generating frequencies corresponding to the signals, an analog to digital converter is used. The different components, as well as the digitized linearized signals, are selectively controlled and fed, respectively, to a microprocessor.

An electronic musical instrument having a number of keys, having tone generators capable of simultaneous tone production, the tone generators being smaller in number than the number of keys. The instrument forms an operation for synthesizing a desired waveform, the operation for synthesizing a desired waveform being performed in a repeating cyclic order with an operation cycle and in which the waveform is transferred to the tone generators and read out therefrom at a rate in accordance with the note of a key being depressed to obtain a desired musical waveform. The device includes a number-of-depressed keys detecting device which counts the number of keys which are actuating the tone generator upon depression. A cycle altering device is provided for changing the operation cycle, as a whole, on the basis of the number of depressed keys, counted by the number-of-depressed keys detecting device. The construction allows for a waveform of a smooth temporal variation to be produced.

A tuning apparatus for a keyboard musical instrument, having a load applicator for applying a load of a predetermined value to a string set up in place, a calculating device for calculating a deviation between a displacement value of the string produced when the load is applied to the string and a preset value of displacement predetermined to give a required frequency of vibration, and a rotating device for turning a tuning pin until the deviation calculated by the calculating device is reduced to zero.

A method for electronically processing and storing musical information involves separating the musical information into a plurality of segments, each representing some portion of a measure, and assigning a sequential time dimension value to each segment. The musical information is also separated into plurality of channels, with each channel representing a sound source and having a sound dimension value assigned to it. The musical information for a given channel and segment is stored in a memory array by associating the musical information corresponding to a given channel and segment with the memory array node specified by the time dimension value and sound dimension value assigned to the given channel and segment.

Root and type of a chord are discriminated at discriminators in accordance with the operation status on a fingerboard. The chord is designated according to a simplified fingering rule predetermined on the fingerboard so as to designate the chord. An automatic accompaniment or a manual play is performed according to the discriminated chord obtained at chord discriminating device.

In an electronic musical instrument of the waveshape memory type including at least one waveshape memory for storing and reproducing sample values of a musical sound wave to be generated, the waveshape memory stores the sample values of the complete waveshape of a musical tone with a shaped envelope.

The musical scale indicator according to a first preferred embodiment of the present invention is composed of two cooperating parts. A base is provided having thereon printed information pertaining to a particular musical instrument and which, in addition, has printed thereon fingering patterns for playing tones on that instrument arranged in a predetermined sequence indicative of any number of desired musical scales. A slidable, clear overlay is slidably connected with the base. The overlay has printed thereon the letter designations for the musical tones arranged in a predetermined sequence so as to cooperate with the fingering patterns indicated on the base in order to selectively indicate to the user the finger positions on the subject musical instrument that will produce the tones of a selected musical scale and simultaneously the finger positions on that instrument that will produce those tones.

External sound signal coupled through a MIC IN terminal is fed through an operating switch panel section to an A/D converter for conversion to a digital signal. The digital signal is stored in a record memory through a waveform R/W controller under the control of a CPU. The digital signal stored in the record memory is read out from the CPU according to control data stored in a work memory to be fed to an external sound system for sounding.

The inventive system comprising a memory for storing the ADSR data, a clock controller for selecting the clock pulses, a counter for counting the output of the clock controller, a data switching means for buffering the output data of the memory, a holding means for holding the output of the data switching means, a comparator for comparing the output of the memory with the output of the holding means, and main controller. The main controller inputs a control signal to control the data access time in the memory and the outputs of the switching means and holding means. According to the present invention, the release data are outputted immediately after the putting off of the keyboard signal to produce more accurate ADSR data.

In an electronic musical instrument of the waveshape memory type including at least one waveshape memory for storing and reproducing sample values of a musical sound wave to be generated, the waveshape memory stores the sample values of the complete waveshape of a musical tone with a shaped envelope.

Support devices for a woodwind musical instrument, and methods for making such support devices. A support device includes a strap for hanging from the neck of the user. Attached to the strap is a brace shaped to receive the instrument. This way the instrument is suspended from the neck of the user. Preferably the brace is such that the strap is attached so that no portion of the strap contacts the instrument, when it is so supported.

A pedal assembly for a bass drum or high hat cymbals. A flat base plate has a resilient pedal board clamped to it with the pedal board inclined to receive a foot. A beater stick is connected with the toe end of the pedal board by a linkage that drives the beater stick against a bass drum when the pedal is depressed. The resiliency of the pedal board returns it to its normal position when foot pressure is withdrawn. The material of which the pedal board is constructed has a modulus of elasticity between about one million and about six million. A striker pad limits the depression of the pedal board to limit the force that the beater stick can apply to the drum.

A portable electronic musical device has a keyboard disposed in a housing connected to a strap and a support plate connected thereto for suspension of housing by strap on shoulders of a person while housing is simultaneously supported on waist of person to allow person to easily move from one geographical position to another while playing instrument. Housing is pivotally connected to support plate by at least one member defining an axis around which housing is rotatable to playing of instrument and to facilitate viewing of hands of person and keys of keyboard while user is playing instrument. To further facilitate playing of instrument and visibility of hands and keys housing is curved with keyboard generally aligned therewith.

A tuning device includes a pitch extraction device with which the pitch of an input signal is extracted and a deviation detection device with which the deviation of the pitch that has been extracted by the pitch extraction device from a standard pitch is detected. The deviation that has been detected by the deviation detection device is displayed by an indicator of a mechanical meter. The tuning device also includes an ultrasonic motor that drives the indicator. A controller drives the ultrasonic motor in conformance with the deviation that has been detected by the deviation detection device. The controller, by driving the indicator using the ultrasonic motor, arranges the indicator in the standard position in those cases where the deviation that has been detected by the deviation detection device is zero, and moves the indicator up to a position in the positive direction that corresponds to the deviation in those cases where the deviation is a positive value and moves the indicator up to a position in the negative direction that corresponds to the deviation in those cases where the deviation is a negative value.

A technique dynamically configures and verifies routing information of broadcast networks using link state protocols in a computer network. According to the novel technique, a router within the broadcast network receives a link state protocol routing information advertisement from an advertising router, e.g., a designated router or other adjacent neighbor. The router learns of a next-hop router (“next-hop”) to reach a particular destination from the advertisement, and determines whether the next-hop is located within the same broadcast network (e.g., subnet) as the designated router. If so, the router further determines whether the next-hop is directly addressable (i.e., reachable), such as, e.g., by checking for link adjacencies to the next-hop or by sending request/reply messages (e.g., echo messages or “ping” messages) to the next-hop. In the event the next-hop for the destination is not directly addressable by the router (e.g., no adjacency or reply), the router installs a route to the destination via the designated router. Otherwise, the router installs a route to the destination via the next-hop.

In the present invention, one or both of an active wheel or a passive wheel is composed of an eccentric transmission wheel and is combined with a synchronous transmission belt for forming an eccentric wheel transmission wheel series, so that when the feet input forces at different angles from the treadle shafts of the treadles to an active wheel shaft combined on the active wheel through cranks, the active wheel forms different transmission speed ratios relative to the passive wheel according to the treadle angle, and random inward packing is performed to the transmission belt (100) of the engage end of the eccentric passive wheel (413) during the transmission for stabling the operation.

A method for electronically controlling a bicycle gearshift comprising at least one derailleur is disclosed, comprising the sequential steps of: a) imparting a movement on the derailleur of the gearshift until the derailleur is in an intended position;b) waiting for a predetermined time period,c) performing a check whether the derailleur is in the intended position, within a possible predetermined tolerance,d) in case said check has a negative outcome, imparting a movement on the derailleur of the gearshift until the derailleur is in the intended position. A derailleur and an electronically servo-assisted bicycle gearshift comprising control electronics comprising modules adapted to carry out the method outlined above are also disclosed.

The present invention is structured by using one or both of an active wheel and a passive wheel being composed of an eccentric transmission wheel and being combined with a synchronous transmission belt for forming an eccentric wheel transmission wheel series, so that in the reciprocal treadle performed by the human's feet, when the feet input forces at different angles from the treadle shafts of the treadles to an active wheel shaft combined on the active wheel through cranks, the active wheel forms different transmission speed ratios relative to the passive wheel according to the treadle angle.

A method for engineering and utilizing large DNA vectors to target, via homologous recombination, and modify, in any desirable fashion, endogenous genes and chromosomal loci in eukaryotic cells. These large DNA targeting vectors for eukaryotic cells, termed LTVECs, are derived from fragments of cloned genomic DNA larger than those typically used by other approaches intended to perform homologous targeting in eukaryotic cells. Also provided is a rapid and convenient method of detecting eukaryotic cells in which the LTVEC has correctly targeted and modified the desired endogenous gene(s) or chromosomal locus (loci) as well as the use of these cells to generate organisms bearing the genetic modification.

The present invention relates to the field of organic chemistry and in particular to organic free radicals used as polarizing agents in the technique of Dynamic Nuclear Polarization (DNP), which involves transferring the polarization of electron spins to the nuclei of a compound whose Nuclear Magnetic Resonance (NMR) is being observed. It concerns Dinitroxide-type Biradical polarizing agents characterized by a rigid linkage between the aminoxyl groups of said nitroxide units. This particular structure enables, at low temperatures and high fields, optimal transfer of polarization and optimal enhancement of NMR/MAS signals of the polarized nuclei of the compound studied.

A process for preparing the compound of the following formula (E): wherein Bn represents a benzyl group, and tBu represents a tert-butyl group, the process including: (a) subjecting the following compound (B) to trifluoroacetylation, wherein tBu represents a tert-butyl group to produce the following compound (C): wherein tBu represents a tert-butyl group, and TFA represents a trifluoroacetyl group; (b) reacting the compound (C) with benzyloxyamine in the presence of a hydroxyl group activating agent to produce the following compound (D): wherein Bn represents a benzyl group, tBu represents a tert-butyl group, and TFA represents a trifluoroacetyl group; and (c) subjecting the compound (D) to detrifluoroacetylation.

An abrasive tool including a CMP pad conditioner having a substrate including a first major surface, a second major surface opposite the first major surface, and a side surface extending between the first major surface and the second major, wherein a first layer of abrasive grains is attached to the first major surface and a second layer of abrasive grains is attached to the second major surface. The conditioner further includes a first sealing member extending in a peripheral direction along a portion of the side surface of the substrate.

The invention relates to a machine part comprising a first physical component, wherein: the first physical component is configured for moving relative to a second physical component; the first physical component has a first surface with a contact area for physical contact with the second physical component; the first physical component is shaped spatially complementarity to the second physical component at the contact area, and a polyelectrolyte layer is present on the first surface at a location of the contact area. The invention further relates to a machine comprising the present machine part and the second physical component. In addition, the invention relates to the use of a polyelectrolyte layer to reduce the friction between the first physical component and the second physical component, and a rolling-elements bearing.

Lubrication additives of the current invention require formation of emulsions in base lubricants, created with an aqueous salt solution plus a single-phase compound such that partitioning within the resulting emulsion provides thermodynamically targeted compounds for boundary layer organization thus establishing anti-friction and/or anti-wear. The single-phase compound is termed “boundary layer organizer”, abbreviated BLO. These emulsion-contained compounds energetically favor association with tribologic surfaces in accord with the Second Law of Thermodynamics, and will organize boundary layers on those surfaces in ways specific to the chemistry of the salt and BLO additives. In this way friction modifications may be provided by BLOs targeted to boundary layers via emulsions within lubricating fluids, wherein those lubricating fluids may be water-based or oil-based.

Device for managing the electrodes for electrical discharge machining EDM machine tools comprises at least one magazine (1) that has a series of individual housings (33) designed to accept and hold exchangeable elements (5) consisting of electrodes (6, 22) mounted on an electrode holder (11a, 11b), and a changer device (2) equipped with a gripper (2) intended to move the exchangeable elements (5) from the individual housings (33) towards the machine and vice versa. A first adapter piece (21) is associated with each of the exchangeable elements (5). This adapter piece (21) surrounds the electrode holder (11a, 11b) and is gripped around its periphery by the gripper (9) of the changer (2) so as to guarantee that the exchangeable element (5) is held precisely. The device further comprises a second adapter piece (32) associated with each of the individual housings (33) of the magazine (1) that are likely to be used.

The invention provides a vertical turret lathe capable of preventing an inner diameter turning tool attached to a turret tool rest from interfering with a workpiece during machining of the outer diameter of the workpiece. The vertical turret lathe comprises a work table that holds a workpiece W1 and rotates, and a working head 40 having a turret tool rest 50 and capable of moving in X-axis and Z-axis directions. A tool holder 70 for holding an inner diameter turning tool T2 via hydraulic pressure is attached to a part of the tool supporting portions 60 of the turret tool rest. The automatic tool changer apparatus 100 includes a turret-type tool magazine 120 and pistons 160 and 162, which mechanically press the pins 74 and 76 of the tool holder 70 and clamp or unclamp the tool T2.

A network component comprising at least one processor coupled to a memory and configured to exchange security information using a plurality of attributes in a management entity (ME) in an optical network unit (ONU) via an ONU management control interface (OMCI) channel, wherein the attributes provide security features for the ONU and an optical line terminal (OLT). Also included is an apparatus comprising an ONU configured to couple to an OLT and comprising an OMCI ME, wherein the OMCI ME comprises a plurality of attributes that support a plurality of security features for transmissions between the ONU and the OLT, and wherein the attributes are communicated via an OMCI channel between the ONU and the OLT and provide the security features for the ONU and the OLT.

The disclosure provides a method and a system for detecting a fiber fault in a Passive Optical Network (PON). The system comprises an optical path detection device, a Wavelength Division Multiplexing (WDM) coupler, a wavelength selection coupler, a branch fiber selector and a wavelength selection router. The detection system is attached to an original PON system, without influencing the operation of the original system while performing the detection. With the disclosure, the problem of being unable to determine whether there is a fault in a branch fiber due to the loss of an optical path detection reflection signal is solved, the branch fiber with a fault can be quickly located and fixed, thus the operational and maintenance costs of an operator are reduced.

A system and method are disclosed for transporting deterministic traffic in a gigabit passive optical network. A system that incorporates teachings of the present disclosure may include, for example, an Optical Line Termination (OLT) for exchanging data traffic in a Gigabit Passive Optical Network (GPON) having a controller programmed to generate a timeslot schedule for transport of a desired bandwidth of constant bit rate (CBR) data traffic by selecting one or more timeslots from periodic frame clusters operating according to a GPON Transmission Convergence (GTC) protocol. Additional embodiments are disclosed.

An optical transceiver has a communications mode and an optical time domain reflectometer (OTDR) mode. The transceiver comprises a transmitter channel and a receiver channel operable, in the communications mode, to respectively transmit and receive communications signals through respective external optical fibers. The transceiver also comprises a guide arrangement for guiding, in the OTDR mode, a reflected OTDR signal along a path from the transmitter channel into the receiver channel. A method of obtaining test data for an optical fiber in an optical data communications subsystem is also disclosed.