A multichannel neural probe for selective chemical delivery at thecellular level

A bulk-micromachined multichannel silicon probe capable of selectively delivering chemicals at the cellular level as well as electrically recording from and stimulating neurons in vivo has been developed. The process buries multiple flow channels in the probe substrate, resulting in a hollow-core device, Microchannel formation requires only one mask in addition to those normally used for probe fabrication and is compatible with on-chip signal-processing circuitry. Flow in these microchannels has been studied theoretically and experimentally. For an effective channel diameter of 10 μm, a channel length of 4 mm, and water as the injected fluid, the flow velocity at 11 torr is about 1.3 mm/s, delivering 100 pl in 1 s. Intermixing of chemicals, with the tissue fluid due to natural diffusion through the outlet orifice becomes significant for dwell times in excess of about 30 min, and a shutter is proposed for chronic use. The probe has been used for acute monitoring of the neural responses to various chemical stimuli in guinea pig superior and inferior colliculus     

红外热成象技术在股骨头坏死疾病针刺疗法中的应用

红外热成象技术可以有效地用于股骨头坏死疾病的诊断和针刺治疗效果的评价，效果优于其它常规方法。     

铜蒸汽激光器双闸流管触发系统的研究

研制成用于钢蒸汽激光器的双间流管触发系统。用两个闸流管并联进行交替触发，总输入电功率达7．8kW。低功率运行时，激光器的效率为0．6％与单间流管激光器的效率一致。     

A fast motion estimation algorithm based on the block sum pyramid

In this correspondence, a fast approach to motion estimation is presented. The algorithm uses the block sum pyramid to eliminate unnecessary search positions. It first constructs the sum pyramid structure of a block. Successive elimination is then performed hierarchically from the top level to the bottom level of the pyramid. Many search positions can be skipped from being considered as the best motion vector and, thus, the search complexity can be reduced. The algorithm can achieve the same estimation accuracy as the full search block matching algorithm with much less computation time.     

Bager第五图的完善

１９８９年发表的Ｂａｇｅｒ第五图，包含关于三角形元素的３５个二次规范画数之间的５１个不等式通过细致的分析，本文给出了其中遗漏的１２个基本不等式     

Transient behavior of subthreshold characteristics of fullydepleted SOI MOSFETs

It has been found that the subthreshold currents of fully depleted silicon-on-insulator (SOI) MOSFETs show a transient behavior under certain front-gate and back-gate voltage conditions. The cause of this anomaly is explained, and applications for the phenomenon are pointed out. Particularly, a simple way to measure the silicon film thickness is suggested     

Adaptive control of arterial blood pressure with a learningcontroller based on multilayer neural networks

The authors discuss a two-model multilayer neural network controller for adaptive control of mean arterial blood pressure (MABP) using sodium nitroprusside. A model with an autoregressive moving average (ARMA), representing the dynamics of the system, and a modified backpropagation training algorithm are used to design the control system to meet specified objectives of design (settling time and undershoot/overshoot) and clinical constraints. The controller is associated with a weighting-determinant unit (WDU) to determine and update the output weighting factor of the parallel two-model neural network for adequate control action and a control-signal modification unit (CMU) to comply with clinical constraints and to suppress the effect of adverse noise and to improve the WDU performance. Extensive computer simulations indicate satisfactory performance and robustness of the proposed controller in the presence of much noise, over the full range of plant parameters, uncertainties, and large variations of parameters     

All-optical photonic switches using integrated inverted asymmetricFabry-Perot modulators and heterojunction phototransistors

InGaAs/GaAs(100) multiple-quantum-well-based inverted cavity asymmetric Fabry-Perot modulators are vertically integrated with GaAs/AlGaAs heterojunction phototransistors to yield all-optical photonic switches. The photonic switches using `normally on' modulator pixels exhibit an output on-off ratio of 12:1 with internal optical gain of 4 dB. The photonic switches using `normally off' modulator pixels yield similar contrast and gain, but exhibit intrinsic bistable behavior. The inverted cavity modulators employed permit utilizing the transparency of the GaAs substrate at the operating wavelength and offer advantages for fabricating large arrays for optical signal processing     

Gate and drain currents in off-state buried-type p-channel LDDMOSFETs

The buried-type p-channel LDD MOSFETs biased at high positive gate voltage exhibit novel characteristics: (1) the ratio of the drain to gate currents is about 1×10^-3 to 5×10^-3; and (2) the gate and drain currents both are functions of only the gate voltage minus the n-well bias. Such characteristics are addressed based on the formation of the surface n ⁺ inversion layer due to the punchthrough of the buried channel to the underlying shallow p-n junction. The measured gate current is due to the Fowler-Nordheim tunneling of electrons from this inversion layer surface and the holes generated within the high-field oxide constitute the drain current. The n⁺ inversion layer surface potential is found to be equal to the n-well bias plus 0.55 V. As a result, both the oxide field and the gate and drain currents are independent of drain voltage