In this article, an adaptive distributed underfrequency load shedding strategy is proposed to ensure the frequency stability of power systems considering the communication latency and frequency recovery. To implement the distributed control, a set of separated zones are adaptively constructed by considering the angular coherence among different buses as the partition radius. While modeling one zone as an energy tissue and simultaneously considering a dispatchable load as an energy cell, a cyber-physical framework is proposed with the multiagent system based on a two-layer energy-cell–tissue structure. In the energy tissue layer, the nearest neighbor consensus algorithm and consensus weighting protocol are combined to address the adaptive coordination of load-shedding tasks for energy tissues under the incomplete information. In the energy cell layer, a distributed model is proposed to determine the optimal location and amount of load shedding based on the proposed sensitivity metric. Simulation results on the IEEE 39-bus system show that the proposed method can achieve better performances in ensuring the load shedding with the communication latency and recovering the frequency level with the load-shedding cost, compared with the existing approaches.

A split based all-digital background calibration for an 18-bit pipelined-successive approximation register (SAR) analog-to-digital converter (ADC) is proposed in this paper. The "split ADC" architecture is exploited to eliminate the signal interference and accelerate the convergence speed of the calibration. The output difference of two channels continuously drives the background calibration algorithm to estimate and correct the error caused by nonlinearities. To guarantee the validity of calibration with different inputs, shuffling scheme is adopted in capacitor array. Different dither signals are injected into two channels to achieve faster convergence, especially under the DC input. In the meanwhile, enough redundancy is introduced to capacitor array to avoid the decrease of input range caused by dither signal. A 4-bit coarse ADC is exploited to alleviate conversion time and provide dither injection. A behavior level model with various nonideal factors is established in MATLAB to prove the availability of calibration for an 18-bit pipelined-SAR ADC. The simulation shows that the ENOB achieves 16.5-bit, the SNDR is increased from 52.4 dB to 100.9 dB and the SFDR is improved from 72.3 dB to 119.6 dB.

We develop a numerical solution algorithm of the nonlinear potential flow equations with the nonlinear free surface boundary condition. A finite difference method with a predictor-corrector method is applied to solve the nonlinear potential flow equations in a two-dimensional (2D) tank. The irregular tank is mapped onto a fixed square domain with rectangular cells through a proper mapping function. A staggered mesh system is adopted in a 2D tank to capture the wave elevation of the transient fluid. The finite difference method with a predictor-corrector scheme is applied to discretize the nonlinear dynamic boundary condition and nonlinear kinematic boundary condition. We present the numerical results of wave elevations from small to large amplitude waves with free oscillation motion, and the numerical solutions of wave elevation with horizontal excited motion. The beating period and the nonlinear phenomenon are very clear. The numerical solutions agree well with the analytical solutions and previously published results.

The paper describes a Yoga training system that is built based on motion replication technique (MoRep), including hardware, virtual scenario and feedback design. The motion replication technique proposed here can determine the similarity between Yoga master and student's postures and then provide feedback on the incorrect body posture of the student through multimodal channels. The key innovations of this project are also discussed.

Replication of human body motion is a very important means to maintain a subject's emotion, knowledge and experience. The replication process requires accurate motion capturing system with sensor technologies to measure postures of human bodies and posture transmission, as well as feedback systems to adjust postures to fit into targeted ones. The sensing and feedback technologies are fundamental building blocks of motion capturing systems, work training system and rehabilitation systems. In particular, the construction of sensing and feedback systems for dynamic postures is much more complicated than that for static postures in terms of the time evolution and non-ridge body. We believe that dynamic postures can be represented by a set of blueprint or code like trajectories of particle of human body movement. Furthermore, we derive that the sensing and feedback systems should be able to establish to directly measure those critical particles without relying on external infrastructures. In the paper, some of those kinds of sensing and feedback devices are presented and some evidences such as feature contours are obtained through analysis of captured data by those devices in order to prove our estimation. We confess that our work is preliminary for this new field, but we hope that the work presented here can lead more efforts to bring out systematic approaches of feature detection and extraction of human postures whose characteristics are different from those of video and audio.

Automatic motion generation for digital character under the real-time user control is a challenging problem for computer graphic research and virtual environment applications such as on-line games. The present study introduces a methodology to generate a glove puppet animation which is controlled by a new input device, called the Smart Glove, capturing the hand motion. An animation system is proposed to generate the puppet animation based on the procedural animation and motion capture data from Smart Glove. As the control of the puppet character in the animation takes into account the design of Smart Glove and the operation of the puppet in reality, the physical hand motion can either activate the designed procedural animation through motion recognition or tune the parameters of the procedural animation to build the new puppet motion, which allows the direct user control on the animation. The potential application and improvement of the current animation system are also discussed.

Evidence from prior research has demonstrated that exocentric views of the environment can facilitate the acquisition of survey knowledge in a virtual environment. The present study examined the effect of different exocentric views on judging the relative direction of objects. During the participants' vertical movement in a virtual room, participants learned the spatial layout in one of three conditions: two-perspective, attentive-elevation, and normal-elevation conditions, where the number of the exocentric perspectives from which the spatial layout was observed was different. After spatial learning, they made the judgment of the relative direction of objects. The analysis of spatial judgment showed that as the number of exocentric perspectives increased, the accuracy improved in the mental representation of spatial vertical information and spatial information in novel directions. Results indicated that the increased number of exocentric perspectives during the vertical movement facilitated the flexible acquisition of survey knowledge. Applications of this study included the design of effective navigation aids in virtual multilevel buildings.

In this paper, we present a novel sensing technique, optical linear encoder (OLE), in which the motion of an optical encoder on a reflective strip is converted to limb joints' goniometric data. A body sensing module is designed to integrate the OLE and an accelerometer. A sensor network of three sensing modules is established via Controller Areas Network (CAN) bus to capture full motion of human arm with a 7-DOF kinematic model. In addition, a statistical study was conducted to confirm the repeatability and reliability of our sensor network. Results demonstrate that the sensor system has strong potential to be used as a low-cost tool for motion capture, and objective arm function evaluation for both short-term and long-term monitoring.

A robotic puppet is developed for studying motion generation and control of highly articulated biomimic mechatronic systems with anatomical motion data of human in real time. The system is controlled by a pair of data gloves tracking human fingers' actions. With the primitives designed in a multilayered motion synthesis structure, the puppet can realize some complex human-like actions. Continuous full body movements are produced on the robotic puppet by combining and sequencing the actions on different body parts using temporal and spatial information provided by the data gloves. Human is involved in the interactive design of the coordination and timing of the body movements of the robotic puppet in a natural and intuitive manner. The methods of motion generation exhibited on the robotic puppet may be applied to the interactive media, entertainment and biomedical engineering.

The present study investigates the displays on the operation desk in two locomotive cabs. Planning the layout of displays provides the fundamental understanding for the design of operation desk. Before planning the layout, designers should know the relevant importance of each display. A method based on fuzzy logic to rank the displays on the operation desk in locomotive cabs was developed. After evaluating the factors which affect display unit rank, the proposed method takes six different fuzzy operators to comprehensively synthesize the results in order to compensate the integration provided by a mixed fuzzy operator. The result has been demonstrated to be rational in the practical design.

A bandwidth allocation scheme for a linear token passing multiplex data bus is proposed based on balancing message transmission time with traffic load to each node. It is proved to provide a network worst case achievable utilization of 50%. Under this allocation scheme, closed-form expressions for the initialized value of token holding timers and token rotation timers in each node are obtained.