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浅谈县级公司面临的竞争与对策
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作者 栗国强 《种子科技》 1993年第6期20-20,共1页
随着社会主义市场经济的逐步建立,种子经营渠道的疏通,种子市场由种子公司独家经营的格局已被打破,随之而来的是国营、集体、个体一齐上,多渠道经营,县级种子公司正面临着一场新的挑战。目前,县级种子公司的竞争对手主要来自三个方面:... 随着社会主义市场经济的逐步建立,种子经营渠道的疏通,种子市场由种子公司独家经营的格局已被打破,随之而来的是国营、集体、个体一齐上,多渠道经营,县级种子公司正面临着一场新的挑战。目前,县级种子公司的竞争对手主要来自三个方面:①与集团公司、名牌公司的竞争。 展开更多
关键词 种子公司 竞争 对策 具级
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Predicting intrinsic disorder in proteins: an overview 被引量:11
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作者 Bo He Kejun Wang +3 位作者 Yunlong Liu Bin Xue Vladimir N Uversky A Keith Dunker 《Cell Research》 SCIE CAS CSCD 2009年第8期929-949,共21页
The discovery of intrinsically disordered proteins (IDP) (i.e., biologically active proteins that do not possess stable secondary and/or tertiary structures) came as an unexpected surprise, as the existence of suc... The discovery of intrinsically disordered proteins (IDP) (i.e., biologically active proteins that do not possess stable secondary and/or tertiary structures) came as an unexpected surprise, as the existence of such proteins is in contradiction to the traditional "sequence →structure →function" paradigm. Accurate prediction of a protein's predisposition to be intrinsically disordered is a necessary prerequisite for the further understanding of principles and mechanisms of protein folding and function, and is a key for the elaboration of a new structural and functional hierarchy of proteins. Therefore, prediction of IDPs has attracted the attention of many researchers, and a number of prediction tools have been developed. Predictions of disorder, in turn, are playing major roles in directing laboratory experiments that are leading to the discovery of ever more disordered proteins, and thereby leading to a positive feedback loop in the investigation of these proteins. In this review of algorithms for intrinsic disorder prediction, the basic concepts of various prediction methods for IDPs are summarized, the strengths and shortcomings of many of the methods are analyzed, and the difficulties and directions of future development of IDP prediction techniques are discussed. 展开更多
关键词 PROTEIN intrinsic disorder prediction method
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Research present situation and analysis on classification of rock drillability
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作者 张志红 马芹永 《Journal of Coal Science & Engineering(China)》 2001年第1期39-45,共7页
Rock drillability reflects the drill bit fragments rock hardly or easily. At present, rock drillability classification indexes have rock single axle compressive strength, point load intensity, fracture stress during c... Rock drillability reflects the drill bit fragments rock hardly or easily. At present, rock drillability classification indexes have rock single axle compressive strength, point load intensity, fracture stress during chiseling, drill speed, chiseling specific work, acoustic parameter, cutting magnitude and so on. Every index reflects rock drillability but isnt overall. It is feasible that using many indexes of fuzzy mathematics method etc. to evaluate rock drillability. 展开更多
关键词 DRILLABILITY ROCK CLASSIFICATION research present situation INDEX
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Secondary Lens Optimization for LED Lamps
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《Journal of Mechanics Engineering and Automation》 2014年第1期46-51,共6页
The purpose of this paper is to present a methodology for optimizing the geometry of the LED (light emitting diode) secondary lens. The research objective is to uniform the illumination distribution on a target plan... The purpose of this paper is to present a methodology for optimizing the geometry of the LED (light emitting diode) secondary lens. The research objective is to uniform the illumination distribution on a target plane for nonimaging application. In order to achieve this, a software that simulates ray tracing is used, in conjunction with a heuristic process for enhancing the optimized parameters that form the geometry of the LED secondary lens. Spherical lenses was opted for optimization due to its lower manufacture complexity. 展开更多
关键词 LED lamps genetic algorithm LENS optimization.
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Information schema constructs for instantiation and composition of system manifestation features
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作者 Shahab POURTALEBI Imre HORVATH 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第9期1396-1415,共20页
Complementing our previous publications, this paper presents the information schema constructs (ISCs) that underpin the programming of specific system manifestation feature (SMF) orientated information management ... Complementing our previous publications, this paper presents the information schema constructs (ISCs) that underpin the programming of specific system manifestation feature (SMF) orientated information management and composing system models. First, we briefly present (1) the general process of pre-embodiment design with SMFs, (2) the procedures of creating genotypes and phenotypes of SMFs, (3) the specific procedure of instantiation of phenotypes of SMFs, and (4) the procedure of system model management and processing. Then, the chunks of information needed for instantiation of phenotypes of SMFs are discussed, and the ISCs designed for instantiation presented. Afterwards, the information management aspects of system modeling are addressed. Methodologically, system modeling involves (1) placement of phenotypes of SMF in the modeling space, (2) combining them towards the desired architecture and operation, (3) assigning values to the parameters and checking the satisfac- tion of constraints, and (4) storing the system model in the SMFs-based warehouse database. The final objective of the reported research is to develop an SMFs-based toolbox to support modeling of cyber-physical systems (CPSs). 展开更多
关键词 System manifestation features (SMFs) Information schema constructs Database schemata SMF genotypes SMFphenotypes SMF instances Soft'ware tool box System-level design Cyber-physieal systems
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