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911.
微生物与人类进化   总被引:1,自引:0,他引:1  
根据现代分子生物学知识和微生物知识,认为基因重组方式可能是人类进化的一种主要方式;并认为微生物能通过基因重组有效介导自身基因和各种生物基因流向人类;从原核生物到真核生物中广泛存在的转座作用可能是微生物介导的基因重组的一种重要方式;高等生物是由低等生物进化而来的,而微生物是进化上最早最低级的生命体。据此,认为微生物可能在人类进化和物种进化中起到了极其重要的作用,甚至可能是一种源泉的作用。其可能方式是  相似文献   
912.
This research investigates how choice-process satisfaction is influenced by limitation of choice option and by the types of features used to represent the options. Studies of choice satisfaction have focused on how satisfied the decision maker feels about the choice that has been made and have overlooked the importance of the process through which the decision maker makes a choice, i.e., choice-process satisfaction. We show that the comparability of choice options through alignable features increases choice-process satisfaction, whereas option limitation (i.e., making one option unavailable from a set of equally attractive options) decreases choice-process satisfaction. Further, this decrease in satisfaction, relative to all options being available, occurs for people who are given a set of options in which the difference features are alignable (i.e., differences of a corresponding dimension) but not for people who are given a set of options in which the difference features are nonalignable (i.e., differences of unique dimensions). We propose that alignable differences are easier to compare and have more weight in people's attribute processing, and thus give rise to a perception of a greater amount of information about the option set that is relevant for choice. Making an option unavailable in this case would have a bigger impact than in a situation in which all options have nonalignable differences. Nonalignable differences are difficult to process and are less likely to make people aware that there is very much information about the options for decision making. This explanation and the interaction effect between option limitation and feature alignability are tested in four experiments.  相似文献   
913.
A Situated Artificial Communicator for Assembly Tasks Summary. In this article we describe a Situated Artificial Communicator for assembly tasks. The main components of the system we are developing are a speech understanding module and a two-arm-robot module. The robot system can be instructed using spontaneous speech. The speech understanding module is based on Combinatory Categorial Grammar, which makes incremental and interactive speech understanding possible. The robot module is provided with multiple sensors and it masters complex assembly operations like peg-in-hole or screwing a nut into a bolt. The architecture and the underlying cognitive principles enable interactive processing that depends on the actual situation and allows the system to take advantage of redundant items of information. Due to these principles our Situated Artificial Communicator is highly robust. Zusammenfassung. In diesem Beitrag stellen wir einen Situierten Künstlichen Kommunikator vor, im vorliegenden Fall ein Robotersystem für Konstruktionsaufgaben. Das Robotersystem kann durch spontansprachliche Anweisungen gesteuert werden. Die Hauptkomponenten des Systems sind eine Sprachverstehenskomponente und eine Zwei-Arm-Roboterkomponente. Die Sprachverstehenskomponente basiert auf der Combinatory Categorial Grammar und ermöglicht eine inkrementelle und interaktive Sprachverarbeitung. Die Roboterkomponente verfügt über eine Vielzahl von Sensoren und beherrscht Montageoperationen wie Stecken und Schrauben. Durch die gewählte Architektur und die zugrundegelegten kognitiven Verarbeitungsprinzipien können Teilkomponenten des Systems der aktuellen Situation entsprechend interagieren und Informationsredundanz nutzen. Das System erhält dadurch eine hohe Robustheit.  相似文献   
914.
儿童理解程度副词的特征   总被引:1,自引:1,他引:0  
本实验用模糊数学方法研究4—9岁儿童对程度副词的理解特征。结果说明9岁儿童的理解达到了成熟水平;幼儿偏向于夸大理解程度副词的词义;7、8岁是发展的转折期。  相似文献   
915.
张灿贤 《管子学刊》2006,(4):109-112
状元殿试对策有着深厚的文化底蕴。它既是对当时性文化现象的全面把握,又是对历时性文化内涵的深刻理解和灵活化用。状元殿试对策作为传统文化的重要载体之一,有着重要的文化研究价值,对当今考试文体也有着诸多启示和借鉴。  相似文献   
916.
论内隐认知   总被引:12,自引:0,他引:12  
人的认知活动是意识过程和无意识过程的统一,该文论证了内隐认知过程的存在性、普遍性、有效性,相对独立性,并就内隐与外显认知过程的关系及其在认识中的作用做了分析和评价。  相似文献   
917.
自改革开放以来,在宗教信仰自由和宽松的社会环境下,农村信教人数增长很快,信教活动有正规合法的,也有非正规不合法的。正如任何事情都有两面性一样,信教现象也不例外。对此现象,我们必须加以重视,对青少年加强科学和无神论世界观的教育与引导,培养出具有共产主义远大理想的社会主义建设人才,促进社会主义精神文明的健康发展。  相似文献   
918.
Qian  Jiehui  Li  Zhuolun  Zhang  Ke  Lei  Quan 《Psychonomic bulletin & review》2020,27(2):341-349
Psychonomic Bulletin & Review - Working memory is considered as a cognitive memory buffer for temporarily holding, processing, and manipulating information. Although working memory for verbal...  相似文献   
919.
Journal of Philosophical Logic - Jeffrey conditionalization is a rule for updating degrees of belief in light of uncertain evidence. It is usually assumed that the partitions involved in Jeffrey...  相似文献   
920.

The maintenance of information in visual working memory has been shown to bias the concurrent processing in favor of matching visual input. The present study aimed to examine whether this bias can act at an early stage of processing to enhance target feature perception in single-item displays. Participants were sequentially presented with two distinct colored stimuli as memory samples and a retro-cue indicating which of the two samples should be maintained for subsequent memory test. During the retention interval, they had to discriminate the gap orientation of a Landolt target presented through a single visual stimulus that could match one or neither of the two samples. Across two experiments, we consistently found that discrimination performance was more accurate when the Landolt target was situated within a stimulus that matched the sample being retained in visual working memory, as compared with when the target was not. This effect cannot be attributed to the mechanism of passive priming, because we failed to observe priming effects when the stimulus containing the target matched the sample that was retro-cued to be irrelevant to the working memory task, as compared to when the stimulus matched neither sample. Given the fact that target stimuli were presented in single-item displays wherein external noise was precluded, the present findings demonstrate that the working memory bias of visual attention operating in the absence of stimulus competition facilitates early perceptual processing at the attended location via signal enhancement.

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