高功率无铝半导体激光器

ＩｎＧａＡｓＰ／ＧａＡｓ激光器抑制暗线缺陷的形成,器件的突然失效及缓慢退化有所减少。研究表明,高功率无铝半导体激光器比有铝ＡｌＧａＡ／ＧａＡｓ激光器具有更高的可靠性。文章分析比较了高功率有铝和无铝半导体激光器的优缺点,介绍了波长为８０８ｎｍ的高功能无铝半导体激光器的发展及国内外目前的研究状况。     

GRINSCH-SQW激光器波导特性的数值分析

分析了具有缓变折射率分别限制单量子讲的波导特性。用有限差分方法解出了波导对于基模的等效折射率。在此基础上，通过计算波导中垂直子激光器结平面方向上的光强过场分布，进而求得有源层的光限制因子及各种波导结构参数对的影响。     

北电区CDMA话务统计与实时监控系统

本文介绍了中国联通青岛分公司为提高CDMA网络质量、提高网络维护效率,开发并投入使用的一套话务统计与实时报警软件(CAS)。     

高功率GaAlAs/GaAsSQW激光器

利用分子束外延生长装置生长出了GaAlAs/GaAs梯度折射率分别限制单量子阱结构材料。利用该材料制作的激光二极管 ,室温连续工作 ,功率为 1W ,斜率效率达到 1 0 4W /A     

分别限制量子阱激光器的载流子限制特性及漏电流

本文在数值求解分别限制量子阶激光器的光增益及阈值电流密度的基础上，计算和分析了漂移和扩散两种机制引起的漏电流对半导体激光器阅值电流密度的影响讨论了激光器的结构参数与漏电流的关系。计算结果和实验值进行了比较。     

基于Proteus的单片机系统设计与仿真

介绍了Proteus软件的特点和功能,并以单片机电子时钟系统为例,详细介绍了应用Proteus的ISIS软件进行单片机系统设计与仿真的实现方法。该方法既能准确验证所设计的系统是否满足技术要求,又能提高系统设计的效率和质量,降低开发成本,具有推广价值。     

GSM公共信道中SCH自适应均衡解调算法研究

针对移动信道多径效应造成的严重的码间干扰(ISI)问题,研究了基于最大似然序列估计(MLSE)的GSM公共信道中SCH自适应均衡解调算法,并对这种自适应均衡解调算法在Jakes移动信道模型环境下的性能进行了分析和计算机仿真,仿真结果表明该自适应均衡解调算法能够很好地克服码间干扰(ISI)问题,性能良好。     

Dopamine receptor blockade and extinction differentially affect behavioral variability.

Dopamine (DA) neurons respond to unexpected food delivery and are inhibited during the omission of expected reward. DA receptor blockade mimics some, but not all, aspects of nonreward (extinction) conditions. It was therefore of interest to ask whether DA receptor blockade produces extinction-like increases in behavioral variability in addition to its well-known operant response-suppressing effects. In the current experiment, rats were trained drug-free on an operant task in which they pressed on a keyboard. Two of the keys led to food on a continuous reinforcement schedule. Both response rates and behavioral variability were measured. Test day administration of D? and D? antagonists SCH23390 and raclopride, like extinction, suppressed responding but, unlike extinction, did not lead to an increase in variability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of cortical and striatal dopamine D1 receptor blockade on cued versus noncued behavioral responses.

Various lines of evidence suggest that disruptions in brain dopamine (DA) transmission produce behavioral impairments that can be overcome by salient response-eliciting environmental stimuli. We examined here whether D1 receptor blockade within striatal or frontal cortical DA target regions would differentially affect head entry responses elicited by an auditory cue compared with those occurring during noncued intertrial intervals. Rats received 2 drug-free 28-trial daily sessions in which an auditory cue was immediately followed by food delivery. On the following day, separate groups of rats received bilateral infusions of D1 antagonist SCH23390 to the dorsomedial striatum (DMS), nucleus accumbens (NAcc) core, or the medial prefrontal cortex (mPFC). SCH23390 infused into the DMS and NAcc core suppressed noncued head entries but had no effect on head entries in response to the auditory cue. SCH23390 infused to the mPFC did not reduce either cued or noncued approach responses. Systemic administration of the drug, in contrast, reduced the frequency of both cued and noncued approaches. The results are consistent with the notion that has emerged from the Parkinson's literature that reduced DA transmission produces behavioral suppression that can be overcome by salient environmental response elicitors, and extends this notion by showing that D1 receptor transmission within the striatum strongly suppresses noncued responses while leaving the identical behavior intact when cued by an environmental stimulus. (PsycINFO Database Record (c) 2011 APA, all rights reserved)