On the Realization of Simulated Inductors with Reduced Parasitic Impedance Effects

In this paper, a method for reducing the parasitic impedance effects of the current feedback operational amplifiers (CFOAs) in an inductor simulator at low frequencies is proposed. Also, two novel grounded inductors employing a current follower (CF) and a second generation current conveyor (CCII) are given to illustrate the parasitic reduction technique clearly. The low frequency restrictions of the proposed inductors due to terminal parasitic resistances can be improved by using the presented parasitic impedance reduction technique. SPICE simulations show that the presented inductor employing CFOAs in a voltage-mode (VM) band-pass and high-pass filter application has lower parasitic effects at low frequencies. In addition to simulation results, experimental test results are given to verify the theory.     

Dynamic simulation of product process

During 90’s Nokia utilized Concurrent Engineering (CE) process in mobile phone business successfully. Strong growing of the company, more complex technologies, maturing markets and changes in competition has increased the need to develop the product process of the company to keep its position as an agile, innovative and productive product developer. Dynamic simulation approach has been one of the activities among other product process re-engineering efforts in the company.This paper describes the approach and “Product Process Decision Simulation” (PPDS) solution as the first implemented application of the approach. A dynamic model of product development has been created and applied to manage product process complex dynamic behavior on system level in order to reduce product development cycle times, slippages and costs as well as improve perceived product quality. The key contribution of the simulation solution is to provoke facilitated discussion in order to gain shared understanding of interdependencies and dynamic causes and effects in product process.The implementation and frequent simulation workshops have started in June 2006 and about 500 R&D people have already participated.     

大型宇航环境仿真器中的气压自适应控制

在国防科技和工业过程中,经常会遇到各种物理量（如温度、压力、速度、湿度以及比重等等）的复杂控制问题。自适应控制是解决此类问题的有效途径之一。本文以大型宇航环境仿真器中的气压控制为例,主要讨论了参数自适应控制的应用及PID自适应控制系统的设计方案及过程。该设计方法对于其他物理量的自适应控制可具有普遍参考价值。     

Light transmission efficiency of daylight guidance systems: An assessment approach based on simulations and measurements in a sun/sky simulator

New and more advanced guidance systems are nowadays available, allowing bringing natural light into buildings and offering potentials for energy savings associated to well-being for occupants. From a design point of view, the key factor is the knowledge of their photometric performances in terms of global light transmission efficiency, so as to predict the daylight availability in an interior space due to an array of guidance systems (or, the other way around, to predict the number of pipes needed to produce a minimum natural light illuminance according to standard requirement) through known analytical methods such as the lumen method. In spite of this, determining the global light transmission efficiency of advanced guidance systems is a quite complicate matter because of the redirecting optical properties these elements rely on even in the case of simple typologies (for instance, passive domes with micro-prismatic profiles and micro-prismatic or holographic films used as pipe’s coating).This paper presents an approach to characterize photometric performances of tubular daylight guidance systems in terms of light transmission efficiency: the global system efficiency is the result of the product of the efficiencies of the three individual components (collector, pipe and diffuser) and each efficiency is determined as the ratio of the flux emitted through the output window to the flux hitting the input window, accounting for both the beam and the diffuse efficiency. The approach, based on both measurements on physical models and simulations, was applied to different typologies of pipes and passive collectors and the obtained data were used to eventually calculate the global efficiency for the analyzed system.     

基于干扰观测器的飞行仿真转台完全跟踪控制

针对飞行仿真转台不断提升的性能要求及其多速率采样的工作特点,提出了一种新的鲁棒完全跟踪控制策略。针对完全跟踪前馈控制依赖于系统精确数学模型的问题,通过引入干扰观测器来消除模型摄动和外部扰动,使得被控对象的特性在给定的频段内始终趋近于标称模型,充分保证了PTC的作用。仿真结果表明即使结合简单的PID闭环控制器,系统的跟踪性能也获得了很大的提升。给出PTC和DOB的具体设计方法,并对方法的有效性进行了对比仿真验证。结果表明,与已有方法相比,所提控制方法对模型摄动和力矩扰动的抑制能力更强,跟踪性能更好。     

Statistical Method Application to Knowledge Base Building for Reactor Accident Diagnostic System

In the development of a knowledge based expert system, one of key issues is how to build the knowledge base (KB) in an efficient way with keeping the objectivity of KB. In order to solve this issue, an approach has been proposed to build a prototype KB systematically by a statistical method, factor analysis.

For the verification of this approach, factor analysis was applied to build a prototype KB for the JAERI expert system DISKET. To this end, alarm and process information was generated by a PWR simulator and the factor analysis was applied to this information to define taxonomy of accident hypotheses and to extract rules for each hypothesis. The prototype KB thus built was tested through inferring against several types of transients including double- failures. In each diagnosis, the transient type was well identified. Furthermore, newly introduced standards for rule extraction showed good effects on the enhancement of the performance of prototype KB.     

新型高效电动静压飞行模拟器运动系统

现代飞行训练模拟器必须是具备高动态响应的长行程的六自由度运动系统。以Stewart六自由度运动平台所形成的飞行训练模拟器的电液伺服系统是用电液伺服阀控制的即为阀控系统,功率损失很大,效率很低,系统中产生的热量需要很大的冷却装置,这又需要浪费附加功率。介绍了一种新型高效电动静压飞行模拟器运动系统,该飞行模拟器的电液伺服系统中不用电液伺服阀,而是采用交流伺服电动机直接驱动定量泵的泵控系统。交流伺服电动机按外部指令信号可实现变向、变速、变转矩的伺服驱动;同时,在系统上采用蓄能器可以实现能量回收和保压。在2008年交付使用的波音787飞行训练模拟器采用了该高效电动静压运动系统。     

基于TMS320F2812和C8051F040的目标测量系统电模拟器研制

本文应用TMS320F2812DSP和C8051F040微处理器,对某型卫星地面电联试系统中的目标测量系统电模拟器进行开发,以实现目标测量系统电模拟器的电接口和通信协议与目标测量系统原型样机的完全一致,同时通过应用软件开发来实现各目标测量系统电模拟器的测量功能。基于TMS320F2812DSP和C8051F040单片机所开发的目标测量系统电模拟器具有处理功能强大、接口功能丰富、软件开发效率高、通用性强等优点。最后将所研制的目标测量系统电模拟器接入某型卫星地面电联试系统中,完成了该卫星地面电联试系统的飞行任务演示闭环试验,从而为某型卫星目标测量系统的方案论证提供了有效的实验和验证平台。     

The acute effects of 3,4-methylenedioxymethamphetamine and methamphetamine on driving: A simulator study

Objectives

Illicit drugs such as MDMA and methamphetamine are commonly abused drugs that have also been observed to be prevalent in drivers injured in road accidents. Their exact effect on driving and driving behavior has yet to be thoroughly investigated.

Methods

Sixty-one abstinent recreational users of illicit drugs comprised the participant sample, with 33 females and 28 males, mean age 25.45 years. The three testing sessions involved oral consumption of 100 mg MDMA, 0.42 mg/kg methamphetamine, or a matching placebo. The drug administration was counter-balanced, double-blind, and medically supervised. At each session driving performance was assessed 3 h and 24 h post drug administration on a computerized driving simulator.

Results

At peak concentration overall impairment scores for driving (F_2,118 = 9.042, p < 0.001) and signaling (F_2,118 = 4.060, p = 0.020) were significantly different for the daytime simulations. Performance in the MDMA condition was worse than both the methamphetamine (p = 0.023) and placebo (p < 0.001) conditions and the methamphetamine condition was also observed to be worse in comparison to the placebo (p = 0.055). For signaling adherence, poorer signaling adherence occurred in both the methamphetamine (p = 0.006) and MDMA (p = 0.017) conditions in comparison to placebo in the daytime simulations.

Conclusions

The findings of this study have for the first time illustrated how both MDMA and methamphetamine effect driving performance, and provide support for legislation regarding testing for the presence of illicit drugs in impaired or injured drivers as deterrents for driving under the influence of illicit drugs.