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11.
The purpose of this article is to show why consciousness and thought are not manifested in digital computers. Analyzing the rationale for claiming that the formal manipulation of physical symbols in Turing machines would emulate human thought, the article attempts to show why this proved false. This is because the reinterpretation of designation and meaning to accommodate physical symbol manipulation eliminated their crucial functions in human discourse. Words have denotations and intensional meanings because the brain transforms the physical stimuli received from the microworld into a qualitative, macroscopic representation for consciousness. Lacking this capacity as programmed machines, computers have no representations for their symbols to designate and mean. Unlike human beings in which consciousness and thought, with their inherent content, have emerged because of their organic natures, serial processing computers or parallel distributed processing systems, as programmed electrical machines, lack these causal capacities. 相似文献
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复合材料预紧力齿连接是一种新型连接方式,具有较高的连接效率。本文对预紧力齿连接平板单齿试件进行拉伸与压缩试验,研究对比两种荷载状态下的承载力和剪应力分布规律,采用数字散斑和有限元接触建模两种方法分析齿剪切面的剪应力分布。通过研究发现,相同参数的单齿试件在拉伸与压缩荷载下的承载力相差不大,但两种荷载下齿剪切面的剪应力分布规律却不同。该结论可以用于预紧力齿连接接头的设计计算中。 相似文献
13.
Concrete filled double skin tubular (CFDST in abbreviation) stub columns consist of double concentric thin steel tubes and filled concrete between them. Their mechanical behaviors under axial compression were investigated experimentally. Two testing parameters considered were inner-to-outer diameters ratio and diameter-to-thickness ratio. Observed failure modes were controlled by the local buckling of both the tubes associated with shearing failure of the filled concrete. Main discussion is given on confinement effect by the outer tube to the filled concrete strength. Equations to estimate their ultimate strengths under compression were proposed based upon the yielding strengths of the tubes and the filled concrete cylinder strength. 相似文献
14.
Elfalleh W Tlili N Nasri N Yahia Y Hannachi H Chaira N Ying M Ferchichi A 《Journal of food science》2011,76(5):C707-C713
This article aims to determine the phenolic, tocopherol contents, and antioxidant capacities from fruits (juices, peels, and seed oils) of 6 Tunisian pomegranate ecotypes. Total anthocyanins were determined by a differential pH method. Hydrolyzable tannins were determined with potassium iodate. The tocopherol (α-tocopherol, γ-tocopherol, and δ-tocopherol) contents were, respectively, 165.77, 107.38, and 27.29 mg/100 g from dry seed. Four phenolic compounds were identified and quantified in pomegranate peel and pulp using the high-performance liquid chromatography/ultraviolet method: 2 hydroxybenzoic acids (gallic and ellagic acids) and 2 hydroxycinnamic acids (caffeic and p-coumaric acids). Juice, peel, and seed oil antioxidants were confirmed by ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) methods. The highest values were recorded in peels with 25.63 mmol trolox equivalent/100 g and 22.08 mmol TE/100 g for FRAP and ORAC assay, respectively. Results showed that the antioxidant potency of pomegranate extracts was correlated with their phenolic compound content. In particular, the highest correlation was reported in peels. High correlations were also found between peel hydroxybenzoic acids and FRAP ORAC antioxidant capacities. Identified tocopherols seem to contribute in major part to the antioxidant activity of seed oil. The results implied that bioactive compounds from the peel might be potential resources for the development of antioxidant function dietary food. 相似文献
15.
The succinyl psyllium derivatives were successfully prepared by reacting psyllium with succinic anhydride, 4-dimethylaminopyridine and tributylamine in N,N-dimethylformamide. Three succinyl psyllium derivatives with different degrees of substitution were prepared and denoted as S-Psy-L, S-Psy-M and S-Psy-H. FT-IR spectrum and 1H NMR of the succinylated psyllium showed that its monoester derivative, with succinyl groups, was formed successfully. The succinyl derivatives were also evaluated for their surface structure, gelling properties, water uptake capacities, swelling volumes, and bile acid-binding abilities in vitro. The results showed that succinylation significantly reduced the gelling properties and swelling ability of psyllium, as well as increased water uptake abilities and bile-acid binding capacities. The results of this study suggested that succinylation could be a potential approach for obtaining novel derivatives of psyllium with improved physicochemical and biological properties for application in functional foods or other consumer products. 相似文献
16.
S.C. MaQ.Q. Cao H.C. XuanC.L. Zhang L.J. ShenD.H. Wang Y.W. Du 《Journal of Alloys and Compounds》2011,509(4):1111-1114
The Ni42.7Mn40.8Co5.2Sn11.3 ribbons were prepared by melt spinning. After heat treatment, the martensitic transformation temperature and Curie temperature of austenite of the annealed ribbons increased remarkably. Inverse and direct magnetocaloric properties were investigated in the melt-spun and annealed ribbons. The effective refrigerant capacities for these ribbons were discussed in this paper. 相似文献
17.
Positive Psychotherapy (PPT) is a therapeutic metatheory and approach that was developed in 1968 by Dr. Nossrat Peseschkian. His contribution to psychotherapy is not to be confused with what is being called PPT and is an outgrowth of Positive Psychology begun by Dr. Martin Seligman in the U.S. Peseschkian's approach to therapy is inherently and systematically integrative, along the lines of being cross-cultural, multidisciplinary, therapeutically, and psychologically intertheoretic. This article presents some basic premises of PPT: the use of stories; having a positive starting point; basic and actual capacities; five-stage therapeutic model; as well as mentioning other aspects of PPT and a case study. PPT is well suited to therapists advocating integrative psychotherapy as demonstrated by empirical research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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《中国科协科普人才发展规划纲要(2010—2020年)》提出,到2020年,要培养和造就一支规模适度、结构优化、素质优良的科普人才队伍,科普人才总量至少比2010年翻一番。科普人才的培养,需要在高等教育环节加强科学传播素质教育。在这方面,以美国麻省理工学院和哥伦比亚大学等为代表的国际知名高校已经开展了多年工作。本文重点介绍了美国麻省理工学院开展科学传播素质教育的情况,并在此基础上,结合中国高等教育的现状,分析了我国在高校中开展科学传播素质教育可从中汲取的经验。 相似文献
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