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Construction errors are inevitable in real cable-strut tensile structures. Nevertheless, the relevant work, especially the monitoring scheme design work, to control the construction errors is lacking. At present, the monitoring schemes always lay out the monitored members in the places with great internal force or great deformation, do not consider the method to control the construction errors and do not explain the method to lay out the monitored members in fundamental theory. To address this situation, the element length error, which is an important construction error affecting the bearing performance, is considered as the factor variable and the fundamental equation of pre-stress deviation and element length error is derived firstly. Next the methods to express the pre-stress deviation, which are only derived from the active cable length errors or from both the active cable and passive cable length errors, are discussed. After that, based on the condition that the errors can be solved and compensated, the least number of monitored members is determined. Moreover, those members sensitive to cable length deviation of active cables are selected as monitored members. In order to evaluate the effect level caused by passive cable length deviation, two evaluation parameters Δ and ρ are further discussed. Finally, one cable-strut tensile structure example is employed to verify the proposed method and the results of the example studies indicate that the least necessary number of monitored members can be achieved for the accurate solution and compensation of active cable length deviations. Different members have different sensitivities to the change of the length in active cables and those members with great sensitivities can be chosen in prior as monitored members. The evaluation parameters Δ and ρ can be used to analyze the source of errors and to evaluate the error effect level caused by the passive cable length deviation.

This Paper chooses variable displacement motor as the driving unit for underwater winch. Based on that, a complete hydraulic control circuit is proposed. The oil circuit can realize the active cable picking and laying automatically. Meanwhile, the motor can be adjusted with infinitely variable speed function. In order to save energy, an automatic unloading circuit is designed. At the same time, considering the complex underwater working environment and bad working conditions, hydraulic clutch is introduced to increase the function of cable passive releasing. The hydraulic circuit has fast response and high fault tolerance, which not only ensures the underwater winch to complete various operations quickly and effectively,but also ensures the safety of all parts of the winch.

Consumer‐grade distance sensors, such as the Microsoft Kinect devices (v1 and v2), have been investigated for use as marker‐free motion monitoring systems for radiotherapy. The radiotherapy delivery environment is challenging for such sensors because of the proximity to electromagnetic interference (EMI) from the pulse forming network which fires the magnetron and electron gun of a linear accelerator (linac) during radiation delivery, as well as the requirement to operate them from the control area. This work investigated whether using Kinect v2 sensors as motion monitors was feasible during radiation delivery. Three sensors were used each with a 12 m USB 3.0 active cable which replaced the supplied 3 m USB 3.0 cable. Distance output data from the Kinect v2 sensors was recorded under four conditions of linac operation: (i) powered up only, (ii) pulse forming network operating with no radiation, (iii) pulse repetition frequency varied between 6 Hz and 400 Hz, (iv) dose rate varied between 50 and 1450 monitor units (MU) per minute. A solid water block was used as an object and imaged when static, moved in a set of steps from 0.6 m to 2.0 m from the sensor and moving dynamically in two sinusoidal‐like trajectories. Few additional image artifacts were observed and there was no impact on the tracking of the motion patterns (root mean squared accuracy of 1.4 and 1.1 mm, respectively). The sensors’ distance accuracy varied by 2.0 to 3.8 mm (1.2 to 1.4 mm post distance calibration) across the range measured; the precision was 1 mm. There was minimal effect from the EMI on the distance calibration data: 0 mm or 1 mm reported distance change (2 mm maximum change at one position). Kinect v2 sensors operated with 12 m USB 3.0 active cables appear robust to the radiotherapy treatment environment. PACS number(s): 87.53 JW, 87.55 N‐, 87.63 L‐

Cable–strut tensile structure is composed of tensile cables and compressive struts; its prestressed forming state is obviously influenced by cable length and tension force, so the key control objects of construction are active forces of tensioned cables, lengths of passively tensioned cables, and outer node coordinates. Error effect analysis is required to obtain rational control indexes. The method of multiple random-error effect analysis including errors of the above three control objects is proposed and described in the text: (1) outer node coordinate errors along the linked cables are regarded as additional length errors of outer linked cables; (2) random cable length errors and tension errors based on probability distribution are introduced into error analysis cases by modifying initial strains of cables; and (3) for avoiding the interaction between passive cable length errors and active cable tension errors, elastic modulus of active cables is modified to small values. According to the statistics of measured cable lengths, cable length errors may not be complied with normal distribution. Therefore, the M-shaped probability distribution is proposed, and derivations of probability density function, cumulative distribution function, and its inverse function are carried out, by which calculated random cable length error distribution is comparatively consistent with measured errors. Taking Yueqing Stadium, a wheel-spoke cable truss with crescent shape, as an example, multiple error analysis including passive cable length errors of M-shaped probability distribution, outer node coordinate errors, and active tension errors of normal distribution is carried out. Some useful conclusions and construction control indexes are obtained.

Currently, there is large-scale interest in developing marine-based energy sources and extensive subsea power cable networks. Despite growing concern that local perturbations in the magnetic field produced by current passing through these cables may negatively affect electromagnetically sensitive marine species, e.g., disrupted migration; few studies have examined free-living animals. We used acoustic biotelemetry tracking data to examine movement behaviors and migration success of a magneto-sensitive fish, late-fall run Chinook (LFC) salmon (Oncorhynchus tshawytscha), in relation to the energization of a magnetic field-producing subsea power cable, as well as other potentially influential environmental parameters. We analyzed detection records of tagged LFC salmon smolts during their out-migration through the San Francisco Bay before and after the installation of an 85-km high-voltage direct-current transmission cable. Cable energization did not significantly impact the proportion of fish that successfully migrated through the bay or the probability of successful migration. However, after cable energization, higher proportions of fish crossed the cable location and fish were more likely to be detected south of their normal migration route. Transit times through some regions were reduced during cable activity, but other environmental factors were more influential. Resource selection models indicated that proximity to the active cable varied by location: migration paths moved closer to the cable at some locations, but further away at others. Overall, cable activity appeared to have mixed, but limited effects on movements and migration success of smolts. Additional studies are recommended to further investigate impacts of subsea cables on fish migrations, including potential long-term consequences.

Active surface adjustment of cable net structures is becoming significant when large-size cable net structures are widely applied in various fields, especially in satellite antennas. A general-duty adjustment method based on active cables is proposed to achieve active surface adjustment or surface profile reconfiguration of cable net structures. Piezoelectric actuators and voice coil actuators are selected for constructing active cable structures and their simplified mechanical models are proposed. A bilevel optimization model of active surface adjustment is proposed based on the nonlinear static model established by the direct stiffness method. A pattern search algorithm combined with the trust region method is developed to solve this optimization problem. Numerical examples of a parabolic cable net reflector are analyzed and different distribution types of active cables are compared.

High-precision cable net reflectors are widely required for future communications and observations. Concerning the improvement of their surface accuracy, the active cable structure constructed by incorporating a piezoelectric (PZT) actuator into flexible cables has been proposed to achieve active shape control or active correction of the reflector surface. Two design stages of the cable net reflector with active cables, the form-finding analysis and active shape adjustment, are investigated. The form-finding analysis is derived from nodal force equilibrium equations by the minimum norm method-solving linear equations. An active shape adjustment method with the aid of active cables is then proposed to find the actuation voltages of PZT actuators for the prescribed shape. The adjustment method is divided into three parts: a finite-element model of the active cable net reflector, an active adjustment optimal model, and its solving method using the multidimensional advance-retreat algorithm. Finally, ...

Active shape adjustment of cable net structures is becoming significant when large-size cable net structures are widely applied in various fields, especially in satellite antennas. The main objective of this paper is three-fold. First, the finite element model of cable net structure with active cables is established. The active cable is constructed by incorporating a PZT actuator into flexible cables. Second, based on the finite element model, the shape adjustment method is proposed to find the optimal actuation voltages for the desired shape. The adjustment models include an analytical solution without constraints and two optimization models with constraints which are evaluated by the quadratic criterion and minmax scheme respectively. Finally, the numerical examples of the flexible cable net structure widely applied to the parabolic reflectors of space antennas have been analyzed. It is found that the quadratic criterion performs better than the minmax scheme for solving shape adjustment problem of cable net structures, and the surface accuracy of the cable net structure with active cables can be well improved by PZT actuators.

Active and passive copper cables for data rates exceeding 10 Gb/s are typically limited to less than 20 m. Optical fiber on the other hand offers superior performance for run length greater than 100 m, but is costly. Although 100 m copper link is demonstrated for 10GBASE-T, it utilizes complex symbols at a lower symbol rate across multiple signaling lanes and dissipates substantial power for DSP. In this paper, we propose a 12 Gbps/lane active cable link that extends copper cables >100 meters using low power and area clocked repeaters powered through the cable that could potentially be embedded in the cable. The quality of the clock in such repeaters is the key component in maintaining a clean signal propagation through long distances. This paper introduces an FIR phase filtering technique in combination with an MDLL to deliver a low jitter forward clock. The total jitter at the end of the cable is 4.4 ps RMS. The link has repeating distances of 8 and 16 meters for data and clock, respectively. Each repeater occupies 1 mm2 of area in a 65-nm CMOS technology and dissipates 48 mW.

Thunderbolt 3 (TBT3) active cable is used for high speed data transmission (2 × 20 Gbps) and high current power delivery (3 amps and 5 amps). Its thermal challenge is to passively dissipate high power from its active components (CDR and SVR) inside the plug and joule heating of high current conductors with very limited outer surface area. A system model including a half TBT3 cable, a mating pair of connectors and a motherboard model are built to investigate ways to meet junction temperature requirement of active components and surface temperature requirements for consumer safety and comfort. The system model of TBT cable includes conduction, convection and radiation and it is validated by comparing simulation results to thermocouple measurements and IR camera readings of cable samples powered up using a system validation board. Once the model is validated, this system model is used to study the impacts of component power levels, cable sizes, plug lengths and motherboard temperatures on the temperature criteria and shows motherboard and cable can be effective heat sinks for active components when designed properly. This makes the model an effective and critical tool to facilitate cable design, and to identify active components power limits. Also, since TBT3 utilizes Type C connector form factor, this model and methodology can be transferred to study other cables with Type C connector as well.

Purpose: To develop an active delivery system that enhances visualization of nitinol cardiac occluder devices during deployment under real-time magnetic resonance imaging (MRI). Materials and Methods: We constructed an active delivery cable incorporating a loopless antenna and a custom titanium microscrew to secure the occluder devices. The delivery cable was tuned and matched to 50Ω at 64 MHz with the occluder device attached. We used real-time balanced steady state free precession in a wide-bore 1.5T scanner. Device-related images were reconstructed separately and combined with surface-coil images. The delivery cable was tested in vitro in a phantom and in vivo in swine using a variety of nitinol cardiac occluder devices. Results: In vitro, the active delivery cable provided little signal when the occluder device was detached and maximal signal with the device attached. In vivo, signal from the active delivery cable enabled clear visualization of occluder device during positioning and deployment. Device release resulted in decreased signal from the active cable. Postmortem examination confirmed proper device placement. Conclusion: The active delivery cable enhanced the MRI depiction of nitinol cardiac occluder devices during positioning and deployment, both in conventional and novel applications. We expect enhanced visibility to contribute to the effectiveness and safety of new and emerging MRI-guided treatments. J. Magn. Reson. Imaging 2012;36:972–978. © 2012 Wiley Periodicals, Inc.

Tensegrity structures are spatial, discrete, and lightweight structures that are composed of struts in compression and pre-stressed cables. Stability is provided by the self-stress state between elements independently of external actions. Tensegrity structures are attractive due to their potential for deployability, ease of tuning and high precision control. Since tensegrity structures have highly coupled behavior, placement of actuators is a primary concern when designing active control systems. This study investigates the active control performance of cable members of a tensegrity bridge. The actuation efficiencies of cable members are evaluated through a multi-criteria approach. The configuration of the control system is thus identified through outranking candidate active members. A multi-objective damage tolerance strategy is then proposed and optimally directed control solutions are identified using stochastic search. Case studies for several damage scenarios are examined to validate results. The most efficient active cable configuration is compared with that needed for deployment. This study is divided into two phases. After the description of a 16 m-span tensegrity bridge, optimally directed locations of active cables are determined in the first phase. Secondly, a procedure to ensure damage tolerance of the structure is proposed. The multi-objective self-repair procedure provides damage tolerance minimizing both maximum deflections in the structure and stresses in the structural members. Results indicate that the control strategy for deployment is a near-optimal solution for damage tolerance. The proposed methodology is applicable to a range of complex active structures. (C) 2011 Elsevier Ltd. All rights reserved.

Broadband digital transmission over cable wires, such as in very-high-speed digital subscriber line 2 systems, applies the discrete multitone technique in combination with a bit-loading procedure. The crosstalk interference among the different cables inside a binder is the major performance degradation in the systems. Different crosstalk cancellation schemes considering computation complexity as well as the quality-of-service (QoS) aspect have been investigated to improve the system performance. Nowadays, driven by the newest high-layer applications the QoS requirements are more critical and a dynamic situation happening quite often in reality has to be considered. In this situation, new active cable lines might significantly influence the existing running lines in terms of achieved data rates. Therefore a successive crosstalk cancellation scheme is presented in this study to deal with the dynamic situation. The performance degradation because of the new active lines is predicted. Based on the prediction a line-independent partial cancellation with successive procedure is performed until the QoS requirements are fulfilled again.

SUMMARY Power cables that have sheaths, usually lead, and are manufactured with bitumen impregnated hessian which degrades over time, act as long grounding electrodes or inject fault current directly into the surrounding soil. As a consequence of this, the MV lines made of this type of cable spontaneously form a very large and complex grounding system around the high-voltage/medium-voltage (HV/MV) distribution substations. The area encompassed by this type of grounding system is much larger than the area occupied by the HV/MV substation itself. Due to this, the grounding system exhibits excellent performance, including a very low value of impedance to ground. The problem with this type of grounding system appears only at the design stage of the HV/MV substation, when safety conditions inside and in the vicinity of this substation should be confirmed by calculation. This paper provides improvements in accuracy to the only existing practical method developed for the analysis of this type of grounding system. The proposed improvement enables a more accurate estimation of active cable line length, grounding impedance of the cable line, the urban area covered by this type of grounding system, as well as grounding impedance of the entire grounding system. Copyright # 2010 John Wiley & Sons, Ltd.

The increasing demand for high data rate (>10Gbps) in LANs at distances spanning ~1 to ~1000m, and the intrinsic limitations of electrical interconnects in that range, have generated a large interest in optical active cables. These cables simplify the building of the interconnect fabric by offering a standard electrical interface, while providing the huge bandwidth and long reach of optics. Today, two technology approaches are competing in the active cable business: one is based on direct modulation of VCSELs operating at ~850nm and uses multimode fibers, while the second uses the third window of fibers (~1550nm) and is based on the monolithic integration of the main optical functions (modulation, splitting, detection) in a CMOS chip, along with the electronics. In this Author’s view, the second approach has several advantages, including: much longer reach, better signal integrity in the optical domain, and a potential for reducing the cost and increasing reliability by leveraging mature CMOS processes and by sharing a single light source across several channels. LuxG, Luxtera’s process integrating electronics and photonics on the same Si chip, is the world’s first incarnation of the second approach into an actual manufacturable and production-worthy CMOS technology (Freescale hip7_SOI). Luxtera has recently commercialized an optical active cable based on LuxG that transmits bidirectional data at 10Gbps on four parallel channels for an aggregate bandwidth of 80Gbps [OFC2010]. A key component of Luxtera’s cable is the high-speed receiver. This is based on an integrated waveguide Ge photodetector and a high impedance amplifier sharing the same Si substrate. The minuscule capacitance of the photodetector (due to the adopted waveguide configuration) and small parasitics allowed the design of an optimized amplifier resulting in a record sensitivity of ~-24dBm at 10Gbps, about 6dB better than typical discrete solutions at similar wavelengths and speed [ISSCC2010]. While the Ge waveguide photodetector is today used in a 10Gbps product, its speed makes it ready to be used in next generation optical transceivers operating at 25Gbps. In this paper, the performance and reliability of LuxG Ge waveguide photodetector will be reported and discussed.

Colloque avec actes et comité de lecture. Internationale.; International audience; Cet article présente un modèle dynamique simplifié du télescope de TALC. Malgré sa simplicité, il est représentatif d?une partie de la dynamique du système, qui ont permis l'élaboration de stratégies de contrôle préliminaires pour amortir les résonances du système. En utilisant des câbles actifs, il a été montré que les résonances peuvent être amorties de façon significative, et que l'autorité du contrôle augmente avec le nombre de câbles actifs. En outre, il a été montré que, même avec une faible valeur du gain de commande, la valeur efficace d'une grandeur représentative du chemin optique peut être réduite par un facteur trois.

Generation of mechanical force is essential for the function of tissue cells, for example during migration, wound healing or rigidity sensing. The traction field of adherent cells can be measured on soft elastic substrates using traction force microscopy (TFM). However, mathematical reconstruction of traction fields effectively requires inversion of the long-ranged elastic equations and therefore is an ill-posed inverse problem. Moreover measurement of the traction pattern alone does not tell us how force is distributed inside the cell. To improve the robustness, resolution and scope of conventional TFM, we have developed a new procedure called model-based TFM (MBTFM). We estimate the distribution of intracellular tension from elastic substrate data by minimizing the difference between the experimentally measured displacement field and the predictions of a detailed theoretical model based on active cable networks. Previously this type of model has been successfully used to predict cell shapes on micropatterned substrates. For MBTFM, we consider not only active network contraction, but also contributions of various types of contractile bundles modeled as contractile one-dimensional line element embedded into the network. Subsequent computer simulations of network contraction and parameter optimization allow us to estimate the most likely distribution of tension over various contractile structures and adhesion sites.

This paper investigates numerically the active tendon control of a cable-stayed bridge in a construction phase. A linear Finite Element model of small scale mock-up of the bridge is first presented. Active damping is added to the structure by using pairs of collocated force actuator-displacement sensors located on each active cable and decentralized first order positive position feedback (PPF) or direct velocity feedback (DVF). A comparison between these two compensators showed that each one has good performance for some modes and performs inadequately with the other modes. A decentralized parallel PPF-DVF is proposed to get the better of the two compensators. The proposed strategy is then compared to the one using decentralized integral force feedback (IFF) and showed better performance. The Finite Element model of the bridge is coupled with a nonlinear cable taking into account sag effect, general support movements, and quadratic and cubic nonlinear couplings between in-plane and out-of-plane motions. Finally, the proposed strategy is used to control both deck and cable vibrations induced by parametric excitation. Both cable and deck vibrations are attractively damped.

Traditionally, structures and control devices are designed separately. Here an integrated approach is proposed and applied to find the least cost solution of a passive and active cable stayed footbridge. The optimization process reduces simultaneously cost, stress, acceleration and displacement. By using an entropy-based procedure a Pareto solution is obtained by unconstrained scalar function minimization and an efficient polynomial convergence algorithm is employed. The designed controller is compared with an active linear quadratic regulator (LQR). Numerical simulations show that both passive and active optimum designs are efficient, with different geometry, mass distribution and cost (22% higher in the passive design).

This paper presents a wearable biopatch prototype for body surface potential measurement. It combines three key technologies, including mixed-signal system on chip (SoC) technology, inkjet printing technology, and anisotropic conductive adhesive (ACA) bonding technology. An integral part of the biopatch is a low-power low-noise SoC. The SoC contains a tunable analog front end, a successive approximation register analog-to-digital converter, and a reconfigurable digital controller. The electrodes, interconnections, and interposer are implemented by inkjet-printing the silver ink precisely on a flexible substrate. The reliability of printed traces is evaluated by static bending tests. ACA is used to attach the SoC to the printed structures and form the flexible hybrid system. The biopatch prototype is light and thin with a physical size of 16 cm x 16 cm. Measurement results show that low-noise concurrent electrocardiogram signals from eight chest points have been successfully recorded using the implemented biopatch. QC 20130805. Updated from accepted to published.

To obtain fast time response plasma properties, electron density and electron temperature, with a Langmuir probe, the applied probe voltage has to be swept at high frequency. Due to the RC characteristics of coaxial cables, an induced noise of a square‐wave form will appear when a sawtooth voltage is applied to the probe. Such a noise is very annoying and difficult to remove, particularly when the probe signal is weak. This paper discusses a noise reduction method using a dual‐cable circuit. One of the cables is active and the other is a dummy. Both of them are of equal length and are laid parallel to each other. The active cable carries the applied probe voltage and the probe current signal. The dummy one is not connected to the probe. After being carefully tuned, the induced noises from both cables are nearly identical and therefore can be effectively eliminated with the use of a differential amplifier. A clean I–V characteristic curve can thus be obtained. This greatly improves the accuracy and the tim...

Different configurations of very fast preamplifiers based on BJTs and capable to operate as active cable line terminators are considered in this paper. The design of such preamplifiers allows one to put the front-end out of radiation “hot” areas and solves the problem of radiation resistant electronics. Noise performance, dynamic range and dependences of gain and input impedance on frequency are computed using the PSPICE 5.0 program.

This paper deals with the computer analysis of a particular class of deployable structures, which we have developed over recent years. These structures consist only of rods, hinged together to form a deployable backbone, of some passive cables, which are slack when the backbone is fully or partially folded but become taut when it is fully deployed, and one or more active cables, which activate deployment and set up suitable states of prestress, once the structure is in its fully deployed configuration. We discuss one aspect of the computer analysis of these structures, namely the task of setting up the equilibrium and flexibility matrices required for the deployment, prestressing and structural response computations of three macro-elements: the active cable, i.e. a slender, constant-tension element consisting of two or more straight segments; the pantograph unit, consisting of two coplanar, straight beams joined by a shear connector; and the backbone module for the octahedral mast, which consists of a flat, square cross of rods and an additional rod going through a pivot-and-slider joint at the centre of the cross. Compact matrices for these elements are derived using a recently developed matrix reduction technique. Three applications of these macro-elements are given, illustrating their use in simple deployable structures.

This paper presents the engineering considerations undertaken in the design of an optical active cable for use in the data center/HPC. We report the characteristics and testing results on our 150 Gbit/s optical active cable.

This paper presents an Intelligent Electrodes and Active Cable based wearable medical system. Within each Intelligent Electrode, an Application Specific Integrated Circuit (ASIC) is integrated which includes a gain-bandwidth selectable analog front-end circuit, an 8-bit SAR ADC and a digital controller. The key of the ASIC is the analog front-end circuit with tunable gain and bandwidth which can be configured for Electrocardiogram (ECG), Electroencephalogram (EEG) or Electromyogram (EMG) measurement. Common mode interference is effectively rejected due to the circuit's high Common Mode Rejection Ratio (CMRR), which is higher than 135 dB up to 100 Hz and better than 110dB up to 1 kHz. Since a dedicated data transmission protocol is implemented on chip, the Intelligent Electrodes can establish a self-organized network and perform synchronous measurements for multiple bio-signals.

We use high-order approximation schemes for the space derivatives in the nonlinear cable equation and investigate the behavior of numerical solution errors by using exact solutions, where available, and grid convergence. The space derivatives are numerically approximated by means of differentiation matrices. Nonlinearity in the equation arises from the Hodgkin-Huxley dynamics of the gating variables for ion channels. We have investigated in particular the effects of synaptic current distribution and compared the accuracy of the spectral solutions with that of finite differencing. A flexible form for the injected current is used that can be adjusted smoothly from a very broad to a narrow peak, which furthermore leads, for the passive cable, to a simple, exact solution. We have used three distinct approaches to assess the numerical solutions: comparison with exact solutions in an unbranched passive cable, the convergence of solutions with progressive refinement of the grid in an active cable, and the simulation of spike initiation in a biophysically realistic single-neuron model. The spectral method provides good numerical solutions for passive cables comparable in accuracy to those from the second-order finite difference method and far greater accuracy in the case of a simulated system driven by inputs that are smoothly distributed in space. It provides faster convergence in active cables and in a realistic neuron model due to better approximation of propagating spikes.

Gossamer space structures are relatively large, flimsy, and lightweight. As a result, they are more easily affected or distortion by space thermal environments compared to other space structures. This study examines the structural integrity of a Five-Meter Ka-Band Inflatable/Self-Rigidizable Reflect Antenna under space thermal environments. To maintain the required accuracy of the reflector under orbital temperature changes, the Gossamer space structures will utilize an active control system, consisting of boundary control actuators and an electrostatic figure control system with a real time closed loop feedback. An experimental system is established to verify the control mechanism with photogrammetric measurement technique and Bragg fiber grating (FBG) sensor technique. The shape control experiments are finished by measuring and analyzing small amplitude distortion of Five-Meter Ka-Band Inflatable/Self-Rigidizable Reflect Antenna based on the active components made of shape memory alloy (SMA) and shape memory polymer composite (SMPC) material. Then, simulations are finished by NASTRAN finite element software with active effect which is considered to be deformation applied on the analytical model. The amplitude of distortion is obtained by the simulations. Both the experimental and numerical solution show that the amplitude of accuracy are developed which proves the feasibility of shape control using shape memory materials and this investigation explores the feasibility of utilizing an active cable based control system of shape memory materials to reduce global distortion due to thermal loading. It is found that through proper assemble of cable lengths and attachment points, significant thermal distortion reduction is achieved. Specifically, radial distortion due to on-orbit thermal loading .

In this paper, novel microchip architecture for a "smart electronic electrode" has been proposed. Furthermore, a new concept for wearable electrocardiography (ECG) monitoring system especially designed for ubiquitous healthcare is described. The patient can wear single Active-Cable connected smart electronic electrodes with wireless transmission of ECG signals to a dedicated Personal Health Assistant (PHA). The system will act as a continuous ECG data and event recorder, which can be used to follow up patients who have survived cardiac arrest or ventricular tachycardia but also for diagnostic purposes for patients with chronic diseases. A microchip prototype for the smart electronic electrode is implemented using UMC 0.18 um process. The post-layout simulation results show that the smart electronic electrode with ultra low power consumption is quite feasible for a hand-held PHA which uses a battery as energy source.

In this paper, a novel wearable electrocardiograph (ECG) monitoring system is presented. Unlike most of the existing holter monitors that are composed of conventional electrodes and multiple cables, the ECG monitoring system proposed here consists of intelligent electrodes and one single Active-Cable. A prototype of a wearable ECG monitoring system is developed and implemented on Xilinx FPGAs. The experimental results show that a reliable performance with high-quality ECG data can be achieved using this novel ECG monitoring system.

Optical links offer many advantages over copper based solutions for 10 Gb/s interconnects, including lighter weight, longer reach and lower power consumption. Copper solutions are either very bulky and of limited reach (10GBASE-CX4) or have high power dissipation (>10W for a 10GBASE-T link). Previous optical solutions for high-volume, short interconnects have been limited by cost and connector cleanliness considerations. In this paper, we describe a duplex active optical cable which overcomes these limitations. Active optical cables not only retain the advantages of optical links with the external characteristics of an electrical cable, but provide additional advantages in performance and yield by eliminating the extra link margins inherent in open optical link standards. A new electrical connector is described which provides excellent return loss performance, high density and a rugged, consumer friendly design. Performance results for 15m graded index plastic optical fiber and 100m multimode glass fiber based cables are reported. Low jitter contribution and power dissipation of ~1W per link are achieved. Finally the design and performance of adapters allowing the use of this cable in present SFP+ and XFP transceiver systems is presented.

Nomenclature u L = unstressed length of a cable L = stressed length of a cable l = horizontal projection of the cable ends vector from I to J h = vertical projection of the cable ends vector from I to J i s = unit vector along ith drag cable i P = the component of external force, executed on ith node, along si i

Power outages can seriously disrupt the digital services over community antenna television (CATV) networks. This paper proposes two novel schemes for the ranging process of the Data Over Cable Service Interface Specification (DOCSIS) protocol, within the dynamic persistent ranging framework, which offer an absolute reduction of up to 34% in a cable network's recovery time with an average of 28%. Based on the number of previously, active cable modems (CM) the CMTS allocates the best backoff start/end and updates them once (single backoff shift, SBS) or continuously (continuous backoff shift, CBS) as soon as a percentage of a non-ranged CMs is reached.

This talk will present a new category of optical interconnection solutions based on an intelligent active cable concept. The inset of the Smart cables is to be fully plug-compatible with existing electrical copper-based cable sockets. By powering upt the Smart cables through the electrical socket the new cable can have active fiber optic elements or active cable equalization to extend the reach of conventional passive copper cables. Specific characterization data will be provided on Alvesta four-channel transceiver solution.

This paper presents a new cable-suspended robot. It is a 7-cable spatial design with a closed-form forward pose kinematics solution. Applications include automated machining, construction, and sculpting. This paper presents two new ideas. First, an independent, passive, six-string-pot-based Cartesian metrology system was built and tested since length measurements through the active drive system may be inaccurate for large-scale systems. Second, we introduce a new active cable tensioning approach wherein we control the displacement of a physical spring in-line with one of the active drive cables in attempt to ensure only positive cable tensions in all active cables. This is compared with an existing particular/homogeneous tensioning solution approach. Simulation examples are presented in this paper; we are currently building the proposed system for future evaluation work.Copyright © 2004 by ASME

In recent theoretical approaches addressing the problem of neural coding, tools from statistical estimation and information theory have been applied to quantify the ability of neurons to transmit information through their spike outputs. These techniques, though fairly general, ignore the specific nature of neuronal processing in terms of its known biophysical properties. However, a systematic study of processing at various stages in a biophysically faithful model of a single neuron can identify the role of each stage in information transfer. Toward this end, we carry out a theoretical analysis of the information loss of a synaptic signal propagating along a linear, one-dimensional, weakly active cable due to neuronal noise sources along the way, using both a signal reconstruction and a signal detection paradigm. Here we begin such an analysis by quantitatively characterizing three sources of membrane noise: (1) thermal noise due to the passive membrane resistance, (2) noise due to stochastic openings and closings of voltage-gated membrane channels (Na+ and K+), and (3) noise due to random, background synaptic activity. Using analytical expressions for the power spectral densities of these noise sources, we compare their magnitudes in the case of a patch of membrane from a cortical pyramidal cell and explore their dependence on different biophysical parameters.

In a parallel development to traditional rigid rehabilitation robotic systems, cable-driven systems are becoming popular. The robowalk expander product uses passive elastic bands in the training of the lower limbs. However, a well-controlled assistance or resistance is desirable for effective walking relearning and muscle training. To achieve well-controlled force during locomotion training with the robowalk expander, we replaced the elastic bands with actuator-driven cables and implemented force control algorithms for regulation of cable tensions. The aim of this work was to develop an active cable-driven robotic system, and to evaluate force control strategies for walking rehabilitation using frequency-domain analysis. The system parameters were determined through experiment-assisted simulation. Then force-feedback lead controllers were developed for static force tracking, and velocity-feedforward lead compensators were implemented to reduce velocity-related disturbances during walking. The technical evaluation of the active cable-driven robotic system showed that force-feedback lead controllers produced satisfactory force tracking in the static tests with a mean error of 5.5%, but in the dynamic tests, a mean error of 13.2% was observed. Further implementation of the velocity-feedforward lead compensators reduced the force tracking error to 9% in dynamic tests. With the combined control algorithms, the active cable-driven robotic system produced constant force within the four cables during walking on the treadmill, with a mean force-tracking error of 10.3%. This study demonstrates that the force control algorithms are technically feasible. The active cable-driven, force-controlled robotic system has the potential to produce user-defined assistance or resistance in rehabilitation and fitness training.

Tensegrity structures are spatial self-stressed pin jointed structures where compression components (struts) are surrounded by tension elements. This paper describes a near full-scale deployable tensegrity footbridge that deploys from both sides and connects at mid-span. Two topologies that differ in terms of symmetry of elements and paths of continuous cables are compared. Although both topologies behave similarly with respect to serviceability criteria, there is a significant difference in behavior during deployment. A two-stage control methodology for the connection of both halves of the footbridge is presented. The control methodology determines active cable length changes based on computational control and measurement of the response of the structure during deployment. Both halves are successfully connected at the end of deployment. (C) 2016 Elsevier Ltd. All rights reserved.