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This work investigates the stability of admittance type haptic devices in the context of a wider range of impedances than previously considered. More specifically, we consider the stable range of mass and damping. The coupled human driving impedance, actuator position control bandwidth, and loop delay are identified as major factors affecting the range of stable impedances. Finally, theoretical results are experimentally verified using a custom one degree of freedom admittance type haptic device.

To understand how the realism of a kinesthetic haptic rendering is affected by the accurate selection of the rendering model parameters, we conducted a preliminary user study where subjects compared three real-world objects to their equivalent haptic rendering. The subjects rated the rendering realism as the model parameters were varied about their nominal values. The results suggest that the required accuracy of various haptic rendering parameters is not equally important when considering the perceived realism.

In this paper, a hybrid underwater profiler with thrusters (HUPT) used for fixed-point ocean observation is presented. A gravity center adjustment module(GCAD) is proposed. It can move two rotating moving mass simultaneously by using one motor which contributes to reducing cost and power consumption. We also propose an attitude adjustment approach to change the yaw angle and the pitch angle rapidly and efficiently based on the lateral thruster and the moving mass respectively. To reach a fixed-point, one kind of motion strategy is put forward which is able to reduce the impact of currents and make the HUPT stay in a fixed activity space.

In this paper, a modeling and control framework of the two-wheel steering unmanned bicycle is presented. We first build the dynamic model of the unmanned bicycle using Lagrange method. And then balance controllers for stationary and moving cases are designed. Simulation results show that the stationary bicycle can keep balance only by the swinging balancer, and the linear quadratic regulator (LQR) controller for moving case works well. Our experimental results about LQR controller are also given.

The building, being one of the largest energy consumers, accounts for over 40% of the global energy consumption. The traditional Heating, Ventilation and Air Conditioning (HVAC) and lighting systems cause considerable energy wastes in the building since they cannot adapt to the time-varying occupancy levels, which is expensive to measure with dedicated sensing systems. We propose an indirect method to estimate occupancy levels based on statistical modeling of environmental and energy data that can be measured by existing building sensor systems. The model can parameterize the empirical distribution of the environment parameters with small training data sets. Furthermore, statistical features are selected by the physical model to reduce the time cumulative effect of environment parameters. The proposed method is evaluated on a real testbed with CO 2 concentration and the total plugs power in the room. Results show that the proposed method can reduce the root mean squared error of the occupancy estimation by 33% compared to that using the empirical distribution.

A low-voltage bandgap reference implemented in circuit is optimized by adjusting the ratio of the resistors, and reducing the working voltage of operational amplifier. It achieves the performance of a temperature coefficient of 25 ppm/oC in the range of 0∼100"C which works under the voltage of 0.8V. The simulated power supply rejection ratio is 46.3dB @1Hz and the line regulation is 1.5mV/V in the range from 0.8V to 1.8V.

IC testing is an essential part of semiconductor manufacturing, the silicon chips are deserved to be tested and characterized carefully to get the variation information, however, the traditional testing methods suffer from time consuming, time costing and large area overhead. Compressive Sensing (CS) illustrates that a signal can be perfectly reconstructed from fewer samples than the Nyquist-Shannon sampling theorem requires. CS takes advantage of the signal's sparseness in some domains, allowing the entire signal to be determined from relatively few measurements. The Linear Dynamical System (LDS) framework is regarded as an important class of parametric models for time-series data. This paper designed an algorithm for the bulk production chip testing based on CS theory. The data to be tested is the numerical variations of chips one by one from the same lot, the purpose of our project is to recover all the data from limited few samples as accurate as possible, and the main idea is to estimate the LDS parameter from compressive measurements.

Researches indicate that the resistance of phase-change material will become larger over the time. Use time-aware based soft-decision error correction code, which needs LLR to decode, can correct the errors in multilevel PCM effectively. Accurate LLR needs to read the resistance accurately, which will lead to a longer transmission latency. In this paper, we proposed a non-uniform correction strategy, which can reduce the read levels maintaining bit-error-rate performance. We use LDPC in correction of 4-level per cell PCM, and get the result via computer simulation.

3D integration with through-silicon-vias(TSVs) is a promising way in circuit design. Due to the large dimensions and the tight space of TSVs, signal transmission and integrity face severe challenge from the capacitive crosstalk of TSVs. This paper proposes a 3*3 TSVs modified Fibonacci based Binary Numeral System (FNS) applied to 3*N mesh to reduce the worst crosstalk delay. Partial encoding which means 9-bit Fibonacci code represent 6-bit binary code is applied to the coding and decoding circuit to make the area overhead lower. The experiment shows that the proposed coding scheme can decrease 31% crosstalk delay time compared with the uncoded situation.