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71.
Paolo Baldan 《Journal of Symbolic Computation》2011,46(3):222-245
It is a known fact that the subobjects of an object in an adhesive category form a distributive lattice. Building on this observation, in the paper we show how the representation theorem for finite distributive lattices applies to subobject lattices. In particular, we introduce a notion of irreducible object in an adhesive category, and we prove that any finite object of an adhesive category can be obtained as the colimit of its irreducible subobjects. Furthermore we show that every arrow between finite objects in an adhesive category can be interpreted as a lattice homomorphism between subobject lattices and, conversely, we characterize those homomorphisms between subobject lattices which can be seen as arrows. 相似文献
72.
为了提高词义消歧性能,提出了一种基于卷积神经网络的消歧方法.以歧义词为中心,向左右两侧连续扩展4个邻接词汇单元,选取其中的词形、词性和语义类作为消歧特征.以消歧特征为基础,使用卷积神经网络来确定歧义词的语义类别.利用SemEval-2007:Task#5的训练语料和哈尔滨工业大学语义标注语料来优化卷积神经网络.使用SemEval-2007:Task#5的测试语料来测试词义消歧分类器的性能,所提方法的消歧平均准确率有提高.实验结果表明,该方法在词义消歧中是可行的. 相似文献
73.
The Delphi method is a systematic, interactive, written method, which relies on a panel of experts. This paper seeks to discuss whether the Delphi method is an appropriate method for obtaining information about governance. In this study we used the Delphi method to assemble information from 10 professionals with vast experience in nature conservation, protected areas and governance. The purpose of this study was to get a better understanding of the scientific governance debate. Three rounds of questionnaires were sent to the selected experts. The results of this Delphi Questionnaire reveal that there is a broad common understanding of protected area governance. They also reveal insights into how individual categories of protected areas will develop in the future. However, the study also shows that specialists are not fully agreed on this point. 相似文献
74.
This study explores the use of citation categories assigned by patent examiners to study overlap of patent portfolios among top wind power firms. Cooperative Patent Classification (CPC) is used to obtain a sample of wind industry patents. CPC is shown to be better than the International Patent Classification for identifying patents relevant to the wind power industry. Results show high inter-firm citation among the top wind industry players that can suggest concentration of innovation. The results can be useful for patent analysts, technology managers and policy makers. 相似文献
75.
76.
《Food Control》2014
In this work the prevalence and serovar diversity of Salmonella in various food products including non-thermally processed food and ready-to-eat (RTE) food in Estonia in 2008–2012 are summarized. The findings demonstrate that the overall prevalence of Salmonella in these food categories was low. A total of 260 (0.54%) of 47,927 food samples were found to be positive for Salmonella, the overall prevalence in non-thermally processed food was 0.81% (256/31,576) and in RTE products only 0.02% (4/16,351). Salmonella was most often isolated from raw eggs and products thereof (2.17%, 5/230), followed by raw meat products (0.95%, 207/21,723), RTE mayonnaises (0.90%, 2/221) and raw meat (0.89%, 38/4252). In the raw meat category, Salmonella was most frequently isolated from turkey meat (6.96%, 11 positive samples out of 158), broiler chicken meat (4.00%, 7/175) and from layer hen meat (2.22%, 11/496). Salmonella was isolated in lesser extent from meat preparations (1.91%, 82/4292), minced meat and mechanically separated meat products (0.97%, 100/10,344) and from raw sausages (0.35%, 25/7087).Altogether 24 different serovars were identified among the 260 Salmonella positive samples. Salmonella Typhimurium was the most frequent serovar (26.90% of the positive samples) and it was isolated most commonly in raw food products. The next most frequent serovars were Salmonella Derby (17.50%), Salmonella Enteritidis (8.37%) and Salmonella Newport (7.57%). The only serovars isolated from the Salmonella positive RTE food samples were Salmonella Infantis (two isolates) and S. Enteritidis (two isolates). 相似文献
77.
近年来在我国现代园林景观建筑中,薄壳建筑结构发挥了重要的作用,分别阐述了薄壳结构的主要类别,分析了几种典型薄壳力学设计计算的基本理念,最后对薄壳结构在园林建筑中的发展前景进行了展望。 相似文献
78.
Comments on the original article Personality traits and the classification of mental Disorders: Toward a more complete integration in DSM–5 and an empirical model of psychopathology by Robert F. Krueger and Nicholas R. Eaton (see record 2010-13810-003). Krueger and Eaton (pp. 97–118, this issue) have provided a trenchant argument for greater use of dimensional approaches in the classification of personality disorders (PDs) in future iterations of the psychiatric nomenclature, and their explication of the importance of personality constructs in models of psychopathology more generally is commendably lucid. We agree that the division of PDs in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM–IV) into 10 categorical diagnoses with arbitrary thresholds does not match existing data and requires significant retooling, and we view the inclusion of dimensional traits as an important component of the provisional Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) proposal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
Comments on the original article Personality traits and the classification of mental Disorders: Toward a more complete integration in DSM–5 and an empirical model of psychopathology by Robert F. Krueger and Nicholas R. Eaton (see record 2010-13810-003). In their article, Krueger and Eaton (pp. 97–118, this issue) advocate for a “more complete and extensive integration of personality traits in future DSMs [Diagnostic and Statistical Manuals of Mental Disorders], via the explicit inclusion of an empirically based, dimensional personality trait model” (p. 97) and review the “diverse ways in which the inclusion of an empirically based personality trait model could constitute a critical innovation in the transition from DSM–IV to DSM-5” (p. 113). Krueger and Eaton’s proposal that (DSM-5) adopt a dimensional personality trait approach exemplifies the difficulties of devising a classification scheme that satisfies the needs of the both the clinical and research communities. In this instance, the challenge is adapting a complex dimensional trait scheme developed and utilized almost exclusively by the research community, for clinical use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
无形产品类别对网上购物认知风险的影响 总被引:1,自引:0,他引:1
为了探究网上购物中无形产品对消费者认知风险的影响,进一步完善网上购物的风险认知理论,本研究采用实验室实验与问卷调查相结合的手段,对60名大学生施测。结果表明:首先对于不同类别的无形商品,消费者的总体认知风险差异显著;其次在网上购买无形商品不仅给消费者带来了财务风险、时间风险、身体风险、绩效风险和心理风险,还有社会风险;最后对于大多数类别的无形商品,身体风险并不是消费者在网上购物时所担心的。结论:消费者在网上购买不同类别的无形产品时所认知到的风险结构是有差异的,在网上购买专业性服务时,消费者认知到的风险是最大的。 相似文献