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21.
This study unites investigations into the linguistic relativity of color categories with research on children's category acquisition. Naming, comprehension, and memory for colors were tracked in 2 populations over a 3-year period. Children from a seminomadic equatorial African culture, whose language contains 5 color terms, were compared with a group of English children. Despite differences in visual environment, language, and education, they showed similar patterns of term acquisition. Both groups acquired color vocabulary slowly and with great individual variation. Those knowing no color terms made recognition errors based on perceptual distance, and the influence of naming on memory increased with age. An initial perceptually driven color continuum appears to be progressively organized into sets appropriate to each culture and language. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Retrieving the answer to a general knowledge question has been shown to involve two metacognitive processes--a feeling-of-knowing that initiates the search of long-term memory and a willingness to continue searching until an answer can be confidently stated. To extend this model, college students were asked to retrieve as many members of 2 natural categories as they could in 1 min. Examination of the points at which they switched categories revealed that they searched longer in categories of higher potency, and they switched earlier when the other category was of higher potency. They also searched the first category longer when they were allowed to switch only once during a trial rather than as often as they wished. It was concluded that feeling-of-knowing maintained search of a category and also contributed to the willingness to continue searching, and the constraint on switching impacted the willingness to continue. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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IP in the edge and ATM in the core are commonplace in today's internetworks. The IETF has proposed a new Quality of Service (QoS) mechanism namely Differentiated Services (DiffServ) for IP networks. On the other hand, QoS is an inherent feature in ATM. It is imperative that IP and ATM QoS interoperate efficiently to provide an end-to-end service guarantee. DiffServ provides a class of service named Assured Forwarding (AF) that does not exactly correlate to any of the service categories offered by ATM. AF is targeted towards a range of applications, such as real-time (rt) that do not require a constant bit rate service provided by Expedited Forwarding, and other non-real-time (nrt) applications that expect a service better than best effort. In this paper we propose the mapping of AF to the Variable Bit Rate (VBR) service category in ATM. VBR is suitable because it is available in the form of rt-VBR and nrt-VBR and could be translated appropriately based on the applications. The mapping is implemented and verified using the LBNL Network Simulator. The results of the experiments show that VBR is a better match for AF than any other service category in ATM.  相似文献   
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We study the class of theories for which solving unification problems is equivalent to solving systems of linear equations over a semiring. It encompasses important examples like the theories of Abelian monoids, idempotent Abelian monoids, and Abelian groups. This class has been introduced by the authors independently of each other as commutative theories (Baader) and monoidal theories (Nutt).We show that commutative theories and monoidal theories indeed define the same class (modulo a translation of the signature), and we prove that it is undecidable whether a given theory belongs to it. In the remainder of the paper we investigate combinations of commutative/monoidal theories with other theories. We show that finitary commutative/monoidal theories always satisfy the requirements for applying general methods developed for the combination of unification algorithms for disjoint equational theories.Then we study the adjunction of monoids of homomorphisms to commutative/monoidal theories. This is a special case of a non-disjoint combination, which has an algebraic counterpart in the corresponding semiring. By studying equations over this semiring, we identify a large subclass of commutative/monoidal theories that are of unification type zero. We also show with methods from linear algebra that unitary and finitary commutative/monoidal theories do not change their unification type when they are augmented by a finite monoid of homomor-phisms, and how algorithms for the extended theory can be obtained from algorithms for the basic theory.  相似文献   
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To further understand the needs of the growing population of elderly drivers and create solutions for safe mobility it is important to understand the driving scenarios and aspects in day to day traffic that may be of challenge for this group. More so, individual differences in how drivers perceive their own driving ability may have an effect on how individuals limit their mobility and/or increase their exposure to risk situations, with a potential negative effect on safety.  相似文献   
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A treatise on order in engineering design research   总被引:4,自引:1,他引:4  
Engineering design research shows a rather fragmented, if not a chaotic, picture. But does it have a hidden order? Can we explore it, or should we impose a reasoning model? This paper looks for the answer in the purpose of engineering design. It is destined to sustain human existence and well being by virtual creation of artifacts and services for the society. To this end, the engineering design discipline should provide a proper body of knowledge. The design knowledge obtained by empirical exploration and/or rational comprehension should be transformed for practical/pragmatic deployment. It was assumed that this purposely streaming of design knowledge gives a unique rationale for engineering design research. Based on this, a framework of reasoning was constructed, including source, channel, and sink categories of knowledge and research of engineering design, respectively. Within each category, research domains, trajectories, and approaches were identified. The semantic relationships of domains, trajectories, and approaches form a hierarchical structure. The proposed framework enables a grounded argumentation about the order of engineering design research, as well as about the articulation of the engineering design knowledge.  相似文献   
29.
Some categorical methods used in developing computer programs are considered. Relevant theorems are proved. Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 3–11, July–August, 2000.  相似文献   
30.
Part 1. The core of the concept analysis method is a dictionary of 43,000 words to each of which is assigned up to 5 of 168 concepts. Computer programs read each word of a text and produce a concept frequency profile of the text.Part 2. Comparisons of concept profiles ofTub andGulliver and Swift's own contemporary texts, as well as a composite text of 18th century writers, reveal thatGulliver is conceptually different fromTub and its coevals. The fourth book ofGulliver (Houyhnhnms) is significantly different from the first three books. The last two books ofGulliver (Laputa and Houyhnhnms) are more likeTub than are the first two books (Lilliput and Brobdingnag).Part 3. The concepts and words supporting these distinctions suggest two strands in Swift's thinking: the first, pessimism about the human condition; the second, interest in the quotidian world. Finally, such issues as disambiguation of homonyms, scoring of phrases, and the role of syntax are considered.Julius Laffal is Associate Clinical Professor of Psychiatry (in Psychology) at Yale University. He was Director of Research and Psychological Services at Connecticut Valley Hospital from 1969 to 1985. He has been Adjunct Professor of Psychology at Wesleyan University, and Professor in Residence, Psychology, at University of Connecticut. He is the author ofNormal and Pathological Language (1965) andA Concept Dictionary of English with Computer Programs for Content Analysis (1990).  相似文献   
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