基于LPC2138的超市收银机系统设计

给出一种基于Philips公司的ARM7 LPC2138微控制器的超市收银管理系统的设计方法。该系统不仅实现商品价目表（PLU）,销售日志保存、记录和打印,中英文字符和数字输入等基本功能,还实现了对超市环境参数监测报警、语音播报及语音识别等功能。     

The effect of nonhuman’s versus human’s external regulation on children’s speech use, manifested self-regulation, and satisfaction during learning tasks

Because of several analytical and methodological critiques on the findings and contexts of children’s private speech (PS), self-regulation learning (SRL), and thinking aloud (TA), the present study was conducted to shed new light on the effect of the nonhuman’s/computer’s versus human’s/teacher’s intervention (C-Condition versus T-Condition) on young children’s speech use, SRL, and satisfaction during learning tasks. Four developmental measurements with novel criteria were used to measure: (1) speech analysis, (3) SRL as a function of task level selection, (3) SRL as a function of task precision, and (4) a friendly-chat questionnaire to measure children’s satisfaction. Two types of intervention (enacted versus verbal encouragement) were applied through computer-based learning environment and investigated by forty preschool children divided by their teachers between the two conditions equivalently. It was hypothesized that children who acted alone (C-Condition) were more PS productive, manifested higher SRL, task performance, and satisfaction. The results confirmed the hypothesis with no significant differential effect of the gender on performance, showed that the injudicious use of encouragement hindered the children’s regulation behavior, and proved that PS and TA elicitation were fully different. However, the results were not confirmed Vygotsky’s view and simultaneously not fully inline with Piaget’s view of self-regulation development.     

抗高功率微波的 PS／2光传输接口设计

微波技术已经广泛地应用于通信和其他领域中,在军事上高功率微波武器已经投入使用。如何在恶劣的电磁干扰环境中提升电子设备的防护能力已经成为一项重要的课题。本文从抗高功率微波的需求出发,从信号光电转换设计着手,设计一种基于光纤传输的PS/2接口,并介绍相关电路。实验结果表明：该技术方案可以很好地满足光纤传输和防护需求,具有良好的工程应用前景。     

O3有效钝化多孔硅的研究

开发了用O3氧化钝化多孔Si（PS）的实用工艺方法。O3的基本作用是对Si-Hx和Si悬挂键（DB）的充分氧化，经过随后158d贮存的老化实验，得到了表面Si—H，键完全被Si-O3膜和Si-烷基膜所替代并覆盖的PS，其光致发光（PL）强度达到稳定的增强，这归因于PS纳米晶粒的表面势垒高度的提高以及量子效率的提高。     

转轴编码器构成的智能仪器混合矩阵面板的实现

介绍转轴编码器的原理，从而提出面板中按键和转轴编码器的混合矩阵连接方案。它具有电路简单、I/O资源占用少、软件实现容易的特点。通过定时中断扫描、基于向量的数据处理、基于FIFO的数据存取、基于时间记录的转轴编码器识别、软件去抖以及PS/2协议的软件实现等技术手段，实现该例的PS/2接口面板，其具有低成本、性能可靠稳定、响应及时、字符可加速输出等优点，并在高端智能仪器中得到很好的应用。     

基于单片机的电脑弹簧机按键板的设计与实现

电脑弹簧机是用来生产弹簧的专用设备,按键板则是实现对弹簧机控制的一个人机交互的操作界面。本文介绍了电脑弹簧机按键板的设计及实现方法。该按键板采用薄膜面板开关的形式,用PS/2协议作为按键板和主机的通信手段,以单片机AT89S51作为处理芯片,设计灵活,使用方便可靠,具有锁键的功能,很好地满足了工业现场需求。它具有的通用性使得其能广泛应用于以PC机为主机的控制系统中。     

移动计算机远程操作台设计与实现

介绍一种用单片机实现的移动计算机远程操作控制台设计方法。该操作台可以直接使用计算机标准PC键盘和显示器，实现计算机远距离无线操作，适用于实验室内移动目标的研究工作。     

金隆公司300kt/a扩改工程吹炼工艺方案的论证

本文介绍了铜锍吹炼主要工艺方案 ,重点分析并对比了PS转炉、闪速吹炼炉工艺技术的先进性、可靠性、环境保护、操作实践以及运行情况 ,得出了基本结论 ,为金隆扩建改造工程吹炼工艺方案的选择提供了依据。     

Morphological and chemical studies of pathological human and mice brain at the subcellular level: correlation between light, electron, and nanosims microscopies

Neurodegenerative diseases induce morphological and chemical alterations in well-characterized regions of the brain. Understanding their pathological processes requires the use of methods that assess both morphological and chemical alterations in the tissues. In the past, microprobe approaches such as scanning electron microscopy combined with an X-ray spectrometer, Proton induced X-ray emission, secondary ion mass spectrometry (SIMS), and laser microprobe mass analysis have been used for the study of pathological human brain with limited success. At the present, new SIMS instruments have been developed, such as the NanoSIMS-50 ion microprobe, that allow the simultaneous identification of five elements with high sensitivity, at subcellular spatial resolution (about 50-100 nm with the Cs(+) source and about 150-200 nm with O(-) source). Working in scanning mode, 2D distribution of five elements (elemental maps) can be obtained, thus providing their exact colocalization. The analysis can be performed on semithin or ultrathin embedded sections. The possibility of using transmission electron microscopy and SIMS on the same ultrathin sections allows the correlation between structural and analytical observations at subcellular and ultrastructural level to be established. Our observations on pathological brain areas allow us to establish that the NanoSIMS-50 ion microprobe is a highly useful instrument for the imaging of the morphological and chemical alterations that take place in these brain areas. In the human brain our results put forward the subcellular distribution of iron-ferritin-hemosiderin in the hippocampus of Alzheimer disease patients. In the thalamus of transgenic mice, our results have shown the presence of Ca-Fe mineralized amyloid deposits.     

Distributed NGD active circuit for RF-microwave communication

This paper is aimed to the investigation on innovative distributed negative group delay (DNGD) circuits for RF communication. Thanks to the analogy between the lumped and distributed circuits, NGD circuit topologies were identified. By using the S-parameter theory, analysis and synthesis methods of these topologies are proposed. The DNGD circuits developed are mainly comprised of a transistor combined with a series resistance ended by a stub. Then, synthesis relations enabling to determine the NGD circuit parameters from the desired NGD and gain values are established. As application, an active phase shifter (PS) operating independently with the frequency based on the cascade of PGD and NGD devices was synthesized. First, an NGD PS with transmission phase of (135 ± 5)° around 2.56 GHz over the bandwidth of about 1.02 GHz was obtained. Then, a two-stage DNGD PS exhibiting 90° with ±10° flatness from 4.1 GHz to 6.8 GHz was designed. The DNGD circuit presented can be used in various telecommunication areas notably for correcting RF/numerical signal delays in the RF-microwave analogue-digital devices.