Bimorph actuator with monolithically integrated CMOS OFET control

We present an electrostrictive polymer bimorph controllable with low voltage through an integrated CMOS OFET control system. We have actuated the device by applying voltages up to 400 V to the control system, and can actuate the control with 60 V switching. The electrostrictor material was used both as the substrate for the transistors and as the dielectric layer for the control circuitry. This allows for a reduction in the number of layers in the structure, minimizing the clamping effect that would compromise the strain capabilities of the device. We have characterized the macroscopic displacement of the structure through a radius of curvature measurement, ranging from 11.4 mm to 7.5 mm depending on the supply voltage provided. The architecture proposed can be scaled to larger system with higher supply voltages.     

粹化自然——关于休憩亭的二三事

项目所在的城市昆山位于苏州与上海之间,有着千年的历史文化沉淀,境内的周庄、镜溪等古镇是典型的江南水乡.近些年,昆山经济的迅猛发展、新旧文化的交织更替与人们日益增高的生活需求,都激烈地冲击着原有的城市格局和地理风貌.昆山市区沿河处大多已开发为提供市民活动的滨河公园,间或穿插着小尺度的商业空间.在此背景下,位于滨河公园内的本项目除了要提供未来可供出租的商业空间外,也需满足作为公园基本配套设施的公厕和休憩等功能需求.     

The triterpenoids of Ganoderma tsugae prevent stress‐induced myocardial injury in mice

Ganoderma mushrooms (Lingzhi in Chinese) have well‐documented health benefits. Ganoderma tsugae (G. tsugae), one of the ganoderma species, has been commercially cultivated as a dietary supplement. Because G. tsugae has high antioxidant activity and because oxidative stress is often associated with cardiac injury, we hypothesized that G. tsugae protects against cardiac injury by alleviating oxidative stress. We tested the hypothesis using a work‐overload‐induced myocardial injury model created by challenging mice with isoproterenol (ISO). Remarkably, oral G. tsugae protected the mice from ISO‐induced myocardial injury. Moreover, the triterpenoid fraction of G. tsugae, composed of a mixture of nine structurally related ganoderic acids (GAs), provided cardioprotection by inhibiting the ISO‐induced expression of Fas/Fas ligand, oxidative stress, and apoptosis. The antioxidant activity of GAs was tested in cultured cardio‐myoblast H9c2 cells against the insult of H₂O₂. GAs dissipated the cellular reactive oxygen species imposed by H₂O₂ and prevented cell death. Our findings uncovered the cardioprotective activity of G. tsugae and identified GAs as the bioactive components against cardiac insults.     

Design of a double microprocessor‐based on‐line process control system

Abstract

A numerical technique for integrating the full Navier‐Stokes and diffusion equations through an initial value problem has been used to investigate the time development of a line buoyant source issuing in a density‐stratified environment. The basic physical features and some structures of the interactions of the motion at the intermediate mixing region are obtained. Results show that the stratification tends to inhibit the flow development of the buoyant source and to encourage the formation of a recirculatory vortex on the lower region near the source and the upper region.     

Applying likelihood on Hopfield neural network for radar tracking

Abstract

The multiple‐target tracking (MTT) algorithm plays an important role in radar systems. Data association is the most important technique to solve the tracking problems associating dense measurements with existing tracks. A new approach applying Likelihood to measurements and existing tracks in a radar system based on Neural Network computation is investigated in this paper. The proposed algorithm will solve both the data association and the target tracking problems simultaneously. With this approach, the matching between radar measurements and existing target tracks can achieve global relevance. Computer simulation results indicate the ability of this algorithm to keep track of targets under various conditions.     

Characteristics of flow field near sea bottom in a combined wave and current motion

Abstract

A reasonable time‐invariant eddy viscosity model is proposed to describe turbulent flow over a rough sea bottom in a combined wave‐current system. The linearized governing equations are solved for the wave and current kinematics both inside and outside the wave boundary layer. The results of velocity profile, friction factor and apparent roughness in a wave‐current motion are presented. The friction factors are shown to be consistent with previous theoretical results for the limiting cases of pure wave and pure current motions. Present results are compared favorably with the available data.     

Experimental and numerical investigations for the free vibration of cantilever trapezoidal plates

Abstract

Based on the advantages of non‐contact and full field measurement, the optical technique called amplitude‐fluctuation electronic speckle pattern interferometry (AFESPI) with an out‐of‐plane setup is employed to investigate the free vibration of cantilever trapezoidal plates with various taper ratios and sweep‐back angles. Twenty different plate configurations are analyzed, including triangular and trapezoidal plates, and the first seven vibration modes of each plate are measured. The AF‐ESPI method is very convenient for measuring vibrating objects because no contact is required in contrast to classical modal analysis using accelerometers. Based on the fact that clear fringe patterns will appear only in resonance, both resonant frequencies and corresponding mode shapes can be obtained experimentally using the present technique. Numerical calculations by finite element method are also performed and the results are compared with the experimental measurements. Excellent agreements are obtained for both results of resonant frequencies and mode shapes. The influences of taper ratios and sweep‐back angles on the vibration behavior of cantilever trapezoidal plates are also demonstrated in terms of the dimensionless frequency parameter.     

Study of relationships among synthesis, microstructure and mechanical properties of lithium aluminosilicate glass-ceramics containing ZnO and MgF2 by synchrotron XRD and XANES

The effect of MgF₂ and ZnO as additives on the microstructure evolution of a lithium aluminosilicate glass-ceramic is studied by X-ray powder diffraction and X-ray absorption near edge structure. The changes of main, secondary phase development and morphology under different additive concentrations are responsible for the variation in flexural strength. The decreased flexural strength (>50 %) of MgF₂-bearing samples can be attributed to the non-uniform microstructure, while the increased flexural strength of the ZnO-doped samples might be due to the decreased residual stress resulting from a reduction of viscosity. In addition, the structural role of Zn ions is changed under different phase evolutions. For highly crystalline samples with commercial-like composition, Zn ions tend to have spinel-like local environments; while in a simplified composition, Zn ions favor hexagonal ZnO-like surroundings. The appearance of significant multiple scattering peaks in the near edge structure indicates Zn ions usually presented in an ordered local environment in high doping level samples (>1 % ZnO or MgF₂).     

Regression trees approach for flow-time prediction in wafer manufacturing processes using constraint-based genetic algorithm

Understanding the factors associated with the flow-time of wafer production is crucial for workflow design and analysis in wafer fabrication factories. Owing to wafer fabrication complexity, the traditional human approach to assigning the due-date is imprecise and prone to failure, especially when the shop status is dynamically changing. Therefore, assigning a due-date to each customer order becomes a challenge to production planning. The paper proposes a constraint-based genetic algorithm approach to determine the flow-time. The flow-time prediction model was constructed and compared with other approaches. Better computational effectiveness and prediction results from the constraint-based genetic algorithm are demonstrated using experimental data from a wafer-manufacturing factory.