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211.
    
Pigeons chose between two options on a concurrent‐chains task with a single response requirement in the initial link. The suboptimal option ended with food 20% of the time whereas the optimal option ended with food 80% of the time. During a Sig‐Both condition, terminal‐link stimuli on both options signaled whether or not food would occur. During a Sig‐Sub condition, terminal‐link stimuli on the suboptimal option provided differential signals, but stimuli on the optimal option did not differentially signal the food and no food outcomes. Initial‐link choices revealed a clear preference for the optimal option in the Sig‐Both condition, but preference shifted toward suboptimality in the Sig‐Sub condition. These findings show that pigeon suboptimal choice is not singularly driven by signal value, as has been suggested, but also by reinforcer frequency.  相似文献   
212.
    
Outstanding advantages of OFDM helps high data rate communication systems such as Digital Video Broadcasting (DVB) and mobile worldwide interoperability for microwave access (mobile Wi-MAX). But, OFDM system grieves from grave issue of high PAPR. In OFDM system data output is superposition of multiple sub-carriers and leads to big data. In this case some instantaneous power output might increase greatly and become far higher than the mean power of system. In order to make Neutrosophic data for less PAPR criteria, Gaussian filter based Costas coding is proposed. This paper also proposes feeding the Orthogonal Frequency Division Multiplexed signal (OFDM) into a phase accumulator to obtain frequency modulation, with the aim of reducing the peak to average power ratio (PAPR). For associated radar with modulated waveform mentioned here can be used to enhance the performance. It is widely used to analyze the variation of the output waveform further, the implementation results using MATLAB show that the ratio of average power to peak power is reducing considerably in comparing with the conventional method. Consequently; the signal can assume to fade in a frequency selective channel without an equalizer.  相似文献   
213.
    
There exists a terminological problem in applied behavior analysis: the term frequency has been used as a synonym for both rate (the number of responses per time) and count (the number of responses). To guide decisions about the use and meaning of frequency, we surveyed the usage of frequency in contemporary behavior‐analytic journals and textbooks and found that the predominant usage of frequency was as count, not rate. Thus, we encourage behavior analysts to use frequency as a synonym for count.  相似文献   
214.
汉语同形歧义词歧义消解的两半球差异   总被引:1,自引:0,他引:1  
实验探讨汉语同形歧义词(homographs)歧义消解的过程及大脑两半球的差异。被试为华中科技大学96名大学生,实验采用词汇判断任务。句子语境呈现在被试的视野中央,探测词在SOA(stimulus onset asynchronism)为100毫秒或400毫秒时呈现在左视野或右视野。结果发现,(1)当SOA为100毫秒时,在左视野(右半球)上,与语境一致的同形歧义词的主要意义得到激活,与语境不一致的次要意义也有一定程度的激活。在右视野(左半球)上,只有与语境一致的同形歧义词的主要意义得到激活。(2)当SOA为400毫秒时,在左、右视野(两半球)上,与语境一致的同形歧义词的主要意义和次要意义都得到激活。结果表明,大脑左半球对汉语歧义词的歧义消解具有一定的优势,语境敏感模型可以较好地解释本实验的结果。  相似文献   
215.
陈宝国  尤文平  王立新 《心理科学》2006,29(6):1515-1517,1495
近年来的大量研究表明,词汇习得的年龄是影响词汇加工的一个重要因素。本文首先阐述了词汇习得年龄效应产生的可能机制,包括语音完整性假设、累计频率假设、任意映射假设和语义假设,然后介绍近年来研究的最新动向,并提出了需要进一步研究的问题。  相似文献   
216.
The rubber hand illusion represents an illusory experience during the mislocalization of own hand when correlated visuotactile stimuli are presented to the actual and fake hands. The visuotactile integration process appears to cause this illusion; the corresponding brain activity was revealed in many studies. In this study, we investigated the effect of the rubber hand illusion on the crossmodal integration process by measuring EEG. The participants who experienced less intensive illusion showed greater congruency effect on reaction time (RT), greater power increase at the parietal zero electrode (Pz) and smaller interelectrode synchrony of the gamma band activity. On the other hand, the participants who experienced more intense illusion showed greater interelectrode synchrony. The results suggested that the gamma band activity in the parietal area reflects the visuotactile integration process and that its synchrony causes the illusory intensity.  相似文献   
217.
Population counts and longitude and latitude coordinates were estimated for the 50 largest cities in the United States by computational linguistic techniques and by human participants. The mathematical technique Latent Semantic Analysis applied to newspaper texts produced similarity ratings between the 50 cities that allowed for a multidimensional scaling (MDS) of these cities. MDS coordinates correlated with the actual longitude and latitude of these cities, showing that cities that are located together share similar semantic contexts. This finding was replicated using a first-order co-occurrence algorithm. The computational estimates of geographical location as well as population were akin to human estimates. These findings show that language encodes geographical information that language users in turn may use in their understanding of language and the world.  相似文献   
218.
We explore the features of a corpus of naturally occurring word substitution speech errors. Words are replaced by more imageable competitors in semantic substitution errors but not in phonological substitution errors. Frequency effects in these errors are complex and the details prove difficult for any model of speech production. We argue that word frequency mainly affects phonological errors. Both semantic and phonological substitutions are constrained by phonological and syntactic similarity between the target and intrusion. We distinguish between associative and shared-feature semantic substitutions. Associative errors originate from outside the lexicon, while shared-feature errors arise within the lexicon and occur when particular properties of the targets make them less accessible than the intrusion. Semantic errors arise early while accessing lemmas from a semantic-conceptual input, while phonological errors arise late when accessing phonological forms from lemmas. Semantic errors are primarily sensitive to the properties of the semantic field involved, whereas phonological errors are sensitive to phonological properties of the targets and intrusions.  相似文献   
219.
The impact of CACREP accreditation on counselor competency has received little empirical investigation. Differences in the frequency and type of ethical misconduct between graduates of CACREP‐accredited and non‐CACREP‐accredited counselor education programs were investigated. Results of a multiway frequency analysis indicated that fully licensed graduates of CACREP‐accredited programs were sanctioned for ethical misconduct significantly less frequently than were graduates of non‐CACREP‐accredited programs. Additionally, the accreditation factor was among the highest‐ranking parameter estimates of expected cell frequencies.  相似文献   
220.
In this study of how the frequency of interaction affects decisions on reward allocation, 320 Chinese adults were randomly assigned to 8 conditions and instructed to read a scenario describing 2 co-workers completing a task and obtaining a bonus. The 8 conditions differed in the type of relationships, the frequency of past interaction between co-workers, and the possibility of future interaction. Each participant was instructed to act as the allocator and to hypothetically allocate a monetary reward to the co-worker. The results indicated that both past interaction and future interaction between the co-workers significantly influenced the allocation decision. These results also suggested that the frequency of 2 individuals' past interaction can be predictive of the closeness of their relationship.  相似文献   
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