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971.
James Hartley 《中国科技期刊研究》2004,15(2):127-129
参考文献表的编排有多种体例形式,并且不同体例中参考文献各著录项的表达也不尽相同。由于期刊大都倾向于采用自己所特定的参考文献著录格式,因而目前已有的参考文献软件并不能给予作者很多帮助,即作者如果将其稿件由某期刊改投到另一种期刊,通常需要改动其中的参考文献表格式和正文中的相关部分。在众多的参考文献表格式中,有两种最为主要。其一是在人文科学中较为常用的哈佛体系(即著者一出版年体系),该体系规定正文中给出引文的作者和出版年,文献书目中的引文按著者姓名的字母顺序和出版年的先后排列。另外一种主要的参考文献表是数字体系(顺序编码制),即正文中给出引文的序号,参考文献表中的各篇文献按其在正文中出现的先后顺序排列。科技论文和医学论文多采用该种体例。本文列举了上述两种体例的格式,并对比了二者的优缺点,认为著者.出版年体系可以使学术论文的读者很方便地了解作者所引用的工作是由谁完成的,而数字体系(顺序编码制)因为简洁,从而可以使读者更为通畅地阅读论文。 相似文献
972.
A. A. Momin M. P. Bankar G. M. Bhoite 《Indian journal of clinical biochemistry : IJCB》2016,31(3):286-293
Elevated plasma triglyceride and non-esterified fatty acid concentrations may cause insulin resistance and type 2 diabetes mellitus. Lipoprotein lipase (LPL) is a rate-determining enzyme in lipid metabolism. A variant in the LPL gene has been identified which alters the penultimate amino acid Serine at 447 to a stop codon (S447X), and results in a truncated LPL molecule lacking the C-terminal dipeptide Ser–Gly. The present study was designed to evaluate the frequency of S447X variant in the LPL gene and its effect on the lipid and lipoprotein levels in type 2 diabetic subjects. The genotype frequency distributions of type 2 diabetes patients and controls were in Hardy–Weinberg equilibrium. Comparison of the genotype and allelic frequencies of S447X in subjects with type 2 diabetics compared to controls demonstrated no significant difference. In subjects with type 2 diabetics having hypertriglyceridemia (TG ≥ 150 mg/dl) compared to diabetics with TG level <150 mg/dl, significant difference in genotype frequency was found among these groups, while allelic frequency of X was significantly differed. Logistic regression analysis showed the negative association of LPL S447X variant with TG and VLDL cholesterol, while no association with total cholesterol, HDL cholesterol and LDL cholesterol was found. The lipid levels except for HDL cholesterol were found to be significantly lower in carriers for S447X than wild type in diabetes group. The decreased level of TG and TG rich lipoprotein in subjects with SNP S447X in LPL, predicts anti-atherogenic activity of carriers for S447X variant in general population as well as type 2 diabetic patients. 相似文献
973.
G. A. Alabi 《Information processing & management》1985,21(6):525-533
This paper presents the results of a comparative cost study of the manual circulation system and experimental automated system in a university library in Nigeria. Two sets of data were collected: one on the existing manual circulation system and the other on the experimental automated system on an Apple II microcomputer. Eight different circulation activities were identified for evaluation for which the direct labor cost of circulating a book on each system was calculated. The experimental automated system was found to be less labor intensive than the manual system, although overall unit cost of book circulation on the automated system was higher than on the manual system ($0.59 and $0.49, respectively). Factors attributed to the higher unit cost on the automated system were the cost of equipment and the low circulation figure. However, the automated system was found to be more effective in providing up-to-date and accurate data required for the monitoring of the library stock. 相似文献
974.
James L. Dolby 《Information processing & management》1977,13(1):69-77
One of the fundamental problems in information science is to distinguish various objects (such as books or journal articles) on the basis of associated values (such as authors and titles). Where the values fail to distinguish two distinct objects we say that the objects are ambigious under the given value assignment. To obtain a measure of ambiguity, it is only necessary to count the number of ways that the objects can be arranged for each set of ambiguous objects, multiply these counts and take logarithms. It is shown that such an approach leads to a measure in the formal sense and that the measure depends only on the definition of equality of values so that it can be simply extended to sets of values and ordered sets of values. It is also shown that it is possible to construct a function of ambiguity that one can call “information” and that the information loss that occurs when distinct values are grouped into equivalence classes (as in the use of search and sort keys) is also a measure. Finally, it is shown that ambiguity and information as here defined are directly related to Shannon's definition of “information” thus tieing this approach to that portion of information theory associated with the derivation of optimal distributions frequently used in information science models. 相似文献
975.
976.
Steven J. Sackett James M. Kelley Peter P. Gillis 《Journal of The Franklin Institute》1977,304(1):47-63
Using our constitutive theory for polycrystalline plasticity, we have calculated characteristic yield conditions for several sample materials in which the dependence of the dislocation velocity on stress is given by an empirical power function. The shape of the yield surfaces for these materials varies resembling that of von Mises when the stress exponent is small and that of Tresca when the exponent is large. Additional examples illustrate the ability of the proposed theory to model such phenomena as the development of anisotropy during plastic deformation, material hardening and softening, the occurrence of upper and lower yield points, and a Bauschinger effect. 相似文献
977.
Synchronous data transmission systems that transmit information over dispersive channels often employ adaptive equalization techniques in the processing of the received signals. Most equalizers presently used in communication systems are of the tapped delay line (TDL) type. In this paper, we propose a class of adaptive equalizers of which the TDL equalizer is a member. Another interesting member of this class is the Laguerre adaptive equalizer which is to be introduced in this paper. The configuration of the Laguerre equalizer is developed. It is found, as shown by the examples, that the Laguerre equalizer is more accurate, and is less sensitive to timing error than the conventional TDL equalizer. 相似文献
978.
This paper deals with the experimental aspects of ultrasonic delay lines in liquid media and is a sequel to a previous paper treating the general theory of such devices.Delay devices employing ultrasonic propagation through liquids have proved satisfactory for delay times of the order of 3 milliseconds or less. Such devices can be made broadband and give excellent reproduction of pulse shape. The design considerations for such devices are discussed and illustrated by actual examples. 相似文献
979.
This paper presents the ongoing case study of a large pharmaceutical organisation currently undertaking a number of changes to their work practices. These collaborative changes are being facilitated by groupware systems. In many instances this has led to the rejection of or resistance to the more complex tools. The paper outlines research, based on a perspective informed by structuration theory, that provides the organisation with an approach to supporting staff in this new ‘collaborative environment’. An example, drawn from the case study, shows how such support might be developed and presents a set of recommendations for supporting a particular group, based on this research schema. 相似文献
980.
In this paper, an algorithm is developed to apply Hann, Hamming, Blackman and related windows directly in the transform domain for the discrete cosine transform and discrete sine transform. These algorithms are useful in applications where windowing is required in order to minimize edge effects caused by implicit symmetries in the transform domain that are not replicated in the real-world data. Examples of such applications include data communication, adaptive system identification and filtering, real-time analysis of financial market data, etc. Software implementations in C language are also given. 相似文献