双向可变表的统一设计

从关系数据库理论的角度出发,讨论了双向可变表的设计原则,并通过一个实例给出了PowerBuilder开发环境下的一种设计实现方案.     

双向电泳实验方法的改良

在进行SDS-聚丙烯酰胺凝胶电泳时,用一种自制的电极凝胶条代替大量电极缓冲溶液。这种特制的阴极与阳极凝胶条所含的电解质成分与pH值彼此不同,有效地缩短了电泳时间,避免了样品在电泳过程中的大量扩散,提高了分辨力,保证了实验结果的稳定性;同时不再需要配制大量缓冲液,简化了实验操作,从而使实验方法变得简便、快速,更适合实验教学。将常规方法与改良方法同时应用于实验教学,并加以比较。统计结果表明,后者优于前者,两者时间差异显著。     

Gain and Noise Properties of Bidirectional EDFAs

建立了考虑ＡＳＥ谱和背景损耗影响的双向掺铒光纤放大器（ＢｉＥＤＦＡ）稳态放大速率方程模型,分析了增益与掺铒光纤长度、输入信号光功率、泵浦光功率及泵浦方式等结构参数之间的关系,研究了单向和双向等功率泵浦下正反向噪声系数随正反向信号光输入功率的变化行为,所得结果可作为ＢｉＥＤＦＡ优化设计的理论依据     

基于WWW的互动式电路实验教学平台

本文阐述了制作Web页面,创立Web服务器,包括应用ASP.NET(Active Sever Page)技术实现应用服务器和应用Access创立数据库,构建一个基于Internet的互动式电路实验教学平台。客户机的资源接受结构采用www的Web页面的形式实现,其架构是通过信息传递机制对话,由客户端发出请求,通过ASP程序将消息传送给服务器,服务器与数据库建立连接进行相应的处理,经传递机制将结果传回客户端,再以Web页面的形式显示出来。整个网站设计体现出在线学习,在线答疑,在线实验仿真分析与设计等特点。     

一种双向聚类协同过滤推荐算法研究

针对传统协同过滤推荐算法在大数据环境下存在数据稀疏性及计算复杂性等问题,提出一种双向聚类协同过滤推荐算法。该算法首先从用户维度和项目维度两个方向分别进行属性聚类,然后在目标用户和目标项目所在类簇中分别使用改进后的相似度计算方法进行协同过滤推荐,最后通过平衡因子综合预测评分并形成最终推荐列表。在 MovieLens 公开数据集上进行实验,结果表明,该算法（DCF）相比传统协同过滤推荐算法（TCF）、基于用户聚类的协同过滤推荐算法（UCF）以及基于项目聚类的协同过滤推荐算法（ICF）,在平均绝对误差上分别降低了 16%、8.1%、7.5%,有效提高了推荐精度。     

Selective reinstatement of stimulus-outcome associations

In two experiments, the possibility of outcome-selective reinstatement of conditioned responding was examined. Evidence for outcome-selective reinstatement of previously extinguished appetitively conditioned magazine responses by rats was observed in both Pavlovian (Experiment 1) and discriminated instrumental conditioning (Experiment 2) procedures. In both experiments, stimulus-elicited magazine responses occurred more in the presence of a stimulus whose reinforcer was reinstated than they did in the presence of another stimulus whose reinforcer was not reinstated. This effect was observed after both brief and extensive amounts of extinction. Outcome-selective reinstatement of instrumental leverpressing, however, was not observed, although nonselective reinstatement of magazine responding and leverpressing was obtained in Experiment 2. Overall, the data from these studies challenge existing theories of reinstatement, and they provide additional evidence of the importance of outcome-specific processes in the control of learned performance.     

Contextual associations in trace conditioning

Rats were given tone-footshock pairings with a 0-, 10-, or 30-sec trace interval between tone offset and shock onset. Half the rats within each trace interval were tested for their conditioned fear of the tone through a lick suppression procedure; the remaining rats were evaluated for their fear of the background or contextual cues through their avoidance of the compartment in which conditioning had occurred. Less conditioning was observed to the tone with increasing trace intervals. However, conditioned fear of the context increased with increases in the trace duration. The ability of the more predictive stimulus, the tone, to overshadow the contextual cues was determined by the tone’s temporal contiguity with the footshock. The need to incorporate temporal parameters within current theories of conditioning is discussed.     

双向移位寄存器的创新应用

用向移位奇寄存器可构成自动量程选择电路,并介绍其工作原理。     

在Linux下利用路由列表实现双向代理

一般情况下，代理服务器都是使本地局域网通过代理服务器访问外部网络，而本文介绍了在Linux操作系统下利用路由列表实现双向代理，即在两个互相独立的子网中实现通过设置的代理服务器互相访问。     

双向自动分支界限特征选择算法

Feature selection ks a process where a miniraal feature subset ks selected from an original feature set according to a certain measure. In this paper, feature relevancy ks defined by an inconsistency rate. A bidirectional automated branch and bound algorithm is presented. It is a new complete search algorithm for feature selection, which performs feature deletion and feature addition in parallel.Its bound ks determined by inconsistency rate of the original feature set, hence termed as ‘automated‘. Experimental study shows that it ks fit for feature selection.     

二维合并双向可调拉普拉斯逆线性判别分析算法

两维的水平可调拉普拉斯逆线性判别分析算法是在两维的水平拉普拉斯逆线性判别分析算法的基础上在类间的拉普拉斯散度矩阵上增加了一个参数来调节得到的,同理得到两维的垂直可调拉普拉斯逆线性判别分析算法.两维合并双向可调拉普拉斯逆线性判别分析算法(2DCBMLIF)是合并水平和垂直两个方向的两维可调拉普拉斯逆线性判别分析算法得到的.在FERET和CMU PIE两个人脸库中,2DCBMLIF同四个算法进行了对比试验,测试结果显示该算法是有效和可行的,2DCBMLIF提高了人脸识别率.     

Preservation of response-outcome associations through extinction

In four experiments, rats learned initial response-outcome (R-O) associations in an instrumental training task. They then were given training of those same responses either with another outcome (Experiments 1 and 2) or with nonreward (Experiments 3 and 4). The presence of the original R-O associations was detected by measuring the depressive effect on responding of devaluing that O by pairing with LiCl. The results indicated that the original R-O associations remained intact through both potentially interfering treatments.     

大学生社团建设现状与对策浅探

大学生社团是校园文化建设的重要组成部分,它的存在和健康发展对高校校园文化建设具有十分重要的作用。随着社会的进步和发展,以及多元文化的冲击,如何建设校园文化,建设怎样的校园文化一直是我们需要思考的问题。本文针对目前高校社团建设中存在的问题进行剖析,进而提出如何加强社团内涵建设,构建校园文化高地的一些思考和构想。     

Sensory-specific associations in flavor-preference reversal learning

In two experiments, we examined the effect of reversal learning on the status of initially learned associations. In Experiment 1, thirsty rats were first taught to associate one flavor with sucrose and another flavor with Polycose. These relations were then reversed in a subsequent phase. One of the nutrients was then devalued by being paired with lithium chloride. The results of a two-bottle flavor-choice test revealed that the most recently learned associations governed performance. In Experiment 2, we aimed to discern whether the initially learned associations in Experiment 1 were weakened or masked by reversal learning. In order to address this question, either a 1-day (Group Immediate) or a 21-day (Group Delayed) retention interval was interpolated between the reversal and devaluation phases. Subsequent flavor-choice tests revealed that Group Immediate avoided the flavor most recently associated with the devalued nutrient but that Group Delayed avoided the flavor that was initially associated with the devalued nutrient. These findings suggest that the second-learned associations do not erase, but transiently mask, the first-learned associations, which subsequently recover over a retention interval. These results suggest a parallel in the mechanisms of extinction and reversal learning.     

融合多层注意力机制与双向LSTM的语义关系抽取

关系抽取是构建如知识图谱等上层自然语言处理应用的基础。针对目前大多数关系抽取模型中忽略部分文本局部特征的问题,设计一种结合实体位置特征与多层注意力机制的双向LSTM网络结构。首先根据位置特征扩充字向量特征,并将文本信息向量化,然后将文本向量化信息输入双向LSTM模型,通过多层注意力机制,提高LSTM模型输入与输出之间的相关性,最后通过分类器输出关系获取结果。使用人工标注的百科类语料进行语义关系获取实验,结果表明,改进方法优于传统基于模式匹配的关系获取方法。     

时间副词“才”的双向语义特征

主观评价性时间副词“才”在语义上具有多重双向性特征:它既可以表示界变,又可以表示量化.“才”表界变时,既能表前向界变又能表后向界变;表量化时,既可以表长时量化又可以表短时量化.“才”与多重双向性语义特征相对应是句法模式上的两两对立,其语法意义可抽象为线性或度量上的相对偏离.     

试论英语口语教学中的双向性原则

本文旨在对英语课堂教学双向性原则的内涵进行探讨,以避免一堂英语口语课过分注重＂教＂或者过分注重＂学＂的片面现象发生,协调好＂教＂与＂学＂的关系,从而上好一堂课。