高速公路汽车自动测速模块FPGA的设计

文章提出了一种基于现场可编程门阵列(FPGA)的速度检测器的硬件实现,并将其应用于车道测速系统中.在实验中表明,测速器的运行频率可达到200兆以上,这样的运行频率可以使系统的反应更加灵敏、快捷,而且测出的速度也更加准确.在传输中,还可以利用基于现场可缩程门阵列(FPGA)的优势,在FPGA里面生成所需要的接口,而无需再增加其他器件,使得成本大大的降低.如对测速器进行一定的修改,其通用性会更加完善,可以应用于更多的领域中.     

基于FPGA的LED点阵显示的设计

本文主要讨论了利用EDA技术设计滚动字幕的问题.首先分析了设计中所用到的相关产品的性能,绘出了总体设计框图及各部分的功能;其次是局部电路详细设计;最后对基于现场可编程门阵列(FPGA)的硬件电路、VHDL语言程序设计及调试方法进行了讨论.     

最小二乘SVM的CR认知引擎设计

认知无线电(CR)的核心是认知引擎设计.为适合变化的无线环境状况,提出了一种基于最小二乘支持向量机的认知无线电认知引擎设计方法,该引擎根据经验知识,动态重配置无线环境参数.在802.11a仿真平台上模拟认知无线电通信系统模型,通过样本值训练支持向量机的分类、回归模型,并利用该模型学习信道特征,建立相应的认知引擎.在对感知信息进行学习前提下,实现满足用户需求的无线通信参数配置功能.仿真结果表明,该认知引擎能有效地实现认知无线电学习重构功能.     

转炉炼钢炉料配比模型的构建与分析

以转炉炼钢中炉料配比模型为研究背景,采用RBF神经网络进行终点预测模型的构建,并结合目标价格函数实现炉料配比模型的构建.同时,利用修正的最速下降法进行了最优配比参数的求解.此外,为提高了模型计算结果的准确性,利用最小二乘法对金属收得率进行修正.经验证,模型计算所得的配比数据较生产实际数据有了较大的改善,实现了初始设定目标——降本增效,具有很好的推广应用价值.     

热卷箱卷取控制关键模型的研究

提出了一种结合带料跟踪和卷取松紧度因子的卷径计算模型,其特点是便于卷径计算精度的修正;提出的带钢尾部长度计算理论完整地描绘了带尾的物理状态,用于尾部定位控制确保了尾部定位的精度;提出的1B托卷辊下降高度模型准确地描绘了其运动轨迹,用于实践取得了良好的控制效果.在工程应用中详细讨论了数学模剐应用的难点和实现办法.     

认知理论下的作文教学序列安排

作为体现思想情感的高级思维活动,作文受制于人的认知发展的制约.心理发展具有阶段性和连续性,阶段性体现出不同年龄阶段的认知水平不同,连续性又让认知水平前后互为基础的继承发展.心理发展的阶段性制约着作文在某一年龄阶段的水平发展;心理发展的连续性又在年龄增长中不断打破阶段性制约,促动心理认知的变化出现,体现在人表达交流的情感思想中.基于这样的心理学认知,基础教育中作文教学要根据心理认知的发展阶段合理安排作文教学序列,这是实现作文教学有效性的前提条件.     

一种基于DDS和PLL的Chirp超宽带信号源设计与实现

Chirp超宽带具有峰值平均功率比(peak to average power ratio,PAPR)接近为1、测距定位能力强等优势,能够有效解决传统的超宽带技术存在的PAPR过大、传输距离短等问题,设计并产生Chirp超宽带信号是实现该通信系统的关键技术之一.提出了一种高性能Chirp超宽带信号源方案,通过采用现场可编程门阵列(field-programmable gate array,FPGA)控制直接数字频率合成(direct digital synthesis,DDS)芯片AD9956产生低频Chirp信号,并结合锁相环(phase locked loop,PLL)技术实现带宽扩展,从而获得Chirp超宽带信号.实验表明, 所设计的Chirp超宽带信号源具有结构简单、可编程、可扩展、性能好及实用性强等优点.     

基于DSP的变频调速SPWM控制实现

阐述了一种以可编程DSP控制器为核心的应用于变频系统中正弦脉宽调制(SPWM)方法的实现.根据控制要求,结合TMS320LF2407A的特点,对实现思路、采样算法、DSP硬件电路设计及软件编程进行了系统的说明,较完整地阐述了变频调速SPWM控制的DSP实现.     

基于交替迭代混沌系统的图像加密算法

基于logistic映射和时空混沌系统,设计了一个密钥长度为256bit的图像分组密码算法,将256bit的明文图像分组加密为等长的密文图像.该算法引入的辅助密钥和设计的迭代次数敏感地依赖于明文分组和密钥,交替迭代混沌系统及Arnold映射实现了像素值的扰乱和位置置乱.计算机仿真和密码分析表明,该算法具有对明文和密钥敏感、密钥空间大和可扩展性强等特点,具有良好的加密效果和较强的抗攻击性能,适用于安全通信领域.      

中厚板生产中的道次修正模型

针对传统板对板的自学习模型不能修正轧件个体差异的缺陷,提出了道次对道次的道次修正模型。该模型利用上道次的实测轧制数据,如实测轧制力、轧制速度、测温仪温度等,通过道次出口厚度再计算模块、钢板温度修正模块和轧制力短期修正模块精确计算出当前钢板的实际状态,然后通过剩余道次再计算模块对后续未轧道次的辊缝进行修正。实际应用表明,该道次修正模型投入使用后,轧制力预报精度和成品厚度精度有了很大提高。     

Emotion regulation and memory: The cognitive costs of keeping one's cool.

An emerging literature has begun to document the affective consequences of emotion regulation. Little is known, however, about whether emotion regulation also has cognitive consequences. A process model of emotion suggests that expressive suppression should reduce memory for emotional events but that reappraisal should not. Three studies tested this hypothesis. Study 1 experimentally manipulated expressive suppression during film viewing, showing that suppression led to poorer memory for the details of the film. Study 2 manipulated expressive suppression and reappraisal during slide viewing. Only suppression led to poorer slide memory. Study 3 examined individual differences in typical expressive suppression and reappraisal and found that suppression was associated with poorer self-reported and objective memory but that reappraisal was not. Together, these studies suggest that the cognitive costs of keeping one's cool may vary according to how this is done. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Divergent cognitive costs for online forms of reappraisal and distraction.

The present study was set out to evaluate the cognitive costs of two major emotion regulation strategies under conditions of increased challenge. Previous studies have established that cognitive reappraisal (construing an emotional event in nonemotional terms) has no cognitive costs. However, in all of these studies, reappraisal was initiated at the emotional situation onset, before emotional response tendencies sufficiently evolved. In the present study, the challenge of regulation strategies was increased by initiating strategies online at a late time point in an emotional situation. Applying this procedure revealed for the first time a cognitive cost for reappraisal and also provided double dissociation between reappraisal and another major cognitive emotion regulation strategy--distraction (diverting attention from an emotional situation via producing neutral thoughts). Specifically, late reappraisal, relative to distraction, resulted in an expenditure of self control resources. Late distraction but not reappraisal impaired memory encoding of the emotional situation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

浅议可信计算

可信计算是在计算和通信系统中广泛使用基于硬件安全模块支持下的可信计算平台,以提高整体的安全性.首先讨论可信计算的发展过程和相关基本概念以及可信计算在我国的发展现状,指出了我国可信计算发展中存在的一些问题,最后提出了通过制定我国标准、提高企业及用户意识的建议来说明我国的可信计算的发展方向.     

Neuropsychological symptom presentation after electrical injury

OBJECTIVE: This study explored the relationship of neuropsychological complaints to accident- and injury-related characteristics, affective state, and work status in a group of electrical injury (EI) patients. METHODS: Sixty-three EI patients and 22 electricians with no history of electrical shock completed the Neuropsychological Symptom Checklist and the Beck Depression Inventory as part of an extensive neuropsychological evaluation. RESULTS: The EI group endorsed significantly more physical, cognitive, and emotional symptoms than did the controls. Symptom complaints were not related to injury parameters or litigation status. Only the time interval between injury and assessment accounted for differences in symptom presentation, with patients in the postacute stages of recovery showing the most cognitive and emotional complaints. CONCLUSION: The neuropsychological syndrome of electrical injury survival includes physical, cognitive, and emotional complaints. Considering that most electrically injured patients are treated within the acute medical setting, greater attention needs to be directed early in the course of treatment toward addressing neuropsychologic and psychiatric issues.     

Empathy and the self: Cognitive and emotional influences on the evaluation of negative affect in others.

Used E. T. Higgins's (see record 1987-34444-001) self-discrepancy model to examine the relation of the self to empathy. In Study 1, Ss read about a target displaying either dejection or agitation because of a self-discrepancy. Ss who possessed the self-discrepancy associated with the target's distress showed greater empathic concern, made more situational attributions, and rated the target's reaction as more appropriate. In Study 2, Ss matched the target on affective and cognitive components of the self. Similarity between observer and target on emotional vulnerability was associated with both affective and cognitive empathic effects. Although similarity on attribute accessibility was associated with cognitive empathic effects, it was associated with affective effects only when the attribute produced a self-discrepancy for an observer. Then only feelings of personal distress showed differences. Results establish a link between the self and empathy and show that a number of effects grouped under empathy respond differently to different similarities between observers and targets. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of subjectivity and intersubjectivity in the reconstruction of dissociated schemas; converging perspectives from psychoanalysis, cognitive science and affective neuroscience.

Therapeutic change involves integration of emotion schemas that have been dissociated. Two types of avoidant dissociation are distinguished: primary dissociation dominated by fragmentary emotional memories; and secondary dissociation involving initial encoding of more organized memories whose meaning is avoided. Reconstruction of dissociated emotion schemas occurs through the referential process which includes three basic components: arousal of the subsymbolic affective core of a dissociated schema in the treatment relationship; connections of subsymbolic processes to symbolic representations in narratives and interactions in the session; and reflection leading to reorganization of the schema. The role of enactive perception and embodied communication as underlying intersubjectivity in the referential process is reviewed. Variations in states of awareness associated with each phase of the process, in both analyst and patient, and their effects on therapeutic change are examined. Current work in cognitive science and affective neuroscience supporting this process model is reviewed. This formulation is largely compatible with Freud's early theory of recollection and “associative working-over” with new emphasis on subjective state and the relational context. Studies of the referential process provide a potential interface between investigations of psychotherapy process and basic cognitive science and neuroscience research. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Look before you regulate: Differential perceptual strategies underlying expressive suppression and cognitive reappraisal.

Successful emotion regulation is important for maintaining psychological well-being. Although it is known that emotion regulation strategies, such as cognitive reappraisal and expressive suppression, may have divergent consequences for emotional responses, the cognitive processes underlying these differences remain unclear. Here we used eye-tracking to investigate the role of attentional deployment in emotion regulation success. We hypothesized that differences in the deployment of attention to emotional areas of complex visual scenes may be a contributing factor to the differential effects of these two strategies on emotional experience. Eye-movements, pupil size, and self-reported negative emotional experience were measured while healthy young adult participants viewed negative IAPS images and regulated their emotional responses using either cognitive reappraisal or expressive suppression. Consistent with prior work, reappraisers reported feeling significantly less negative than suppressers when regulating emotion as compared to a baseline condition. Across both groups, participants looked away from emotional areas during emotion regulation, an effect that was more pronounced for suppressers. Critically, irrespective of emotion regulation strategy, participants who looked toward emotional areas of a complex visual scene were more likely to experience emotion regulation success. Taken together, these results demonstrate that attentional deployment varies across emotion regulation strategies and that successful emotion regulation depends on the extent to which people look toward emotional content in complex visual scenes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Age differences in poignancy: Cognitive reappraisal as a moderator.

Poignancy is defined as a mixed emotional experience that arises when one faces meaningful endings. According to socioemotional selectivity theory (Carstensen, 2006), when people are aware of the finitude of time, they tend to experience more poignancy. In Study 1, we found that Chinese younger, but not older, participants experienced more poignancy under time limitations. In Study 2, we found that an emotion regulation strategy—namely, cognitive reappraisal—moderated the relationship between limited time and poignancy, such that the increases in poignancy under time limitations were found only among older Chinese participants with lower levels of cognitive reappraisal but not among those with higher levels of cognitive reappraisal. These findings contribute to the existing literature on poignancy by showing that not every older adult exhibits poignancy in the face of an ending: The poignancy phenomenon may occur among only older adults who are less likely to use an emotion regulation strategy, such as cognitive reappraisal, to reinterpret the anticipated ending. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive reappraisal of negative affect: Converging evidence from EMG and self-report.

Prior psychophysiological studies of cognitive reappraisal have generally focused on the down-regulation of negative affect, and have demonstrated either changes in self-reports of affective experience, or changes in facial electromyography, but not both. Unfortunately, when taken separately, these measures are vulnerable to different sources of bias, and alternative explanations might account for changes in these indicators of negative affect. What is needed is a study that (a) obtains measures of self-reported affect together with facial electromyography, and (b) examines the use of reappraisal to regulate externally and internally generated affective responses. In the present study, participants up- or down-regulated negative affect in the context of both negative and neutral pictures. Up-regulation led to greater self reports of negative affect, as well as greater corrugator and startle responses to both negative and neutral stimuli. Down-regulation led to lesser reports of negative affect, and lesser corrugator responses to negative and neutral stimuli. These results extend prior research by (a) showing simultaneous effects on multiple measures of affect, and (b) demonstrating that cognitive reappraisal may be used both to regulate responses to negative stimuli and to manufacture a negative response to neutral stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)