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1.
2.
The function of a protein is closely correlated to its subcellular location. Is it possible to utilize a bioinformatics method to predict the protein subcellular location? To explore this problem, proteins are classified into 12 groups (Protein Eng. 12 (1999) 107-118) according to their subcellular location: (1) chloroplast, (2) cytoplasm, (3) cytoskeleton, (4) endoplasmic reticulum, (5) extracellular, (6) Golgi apparatus, (7) lysosome, (8) mitochondria, (9) nucleus, (10) peroxisome, (11) plasma membrane and (12) vacuole. In this paper, the neural network method was proposed to predict the subcellular location of a protein according to its amino acid composition. Results obtained through self-consistency, cross-validation and independent dataset tests are quite high. Accordingly, the present method can serve as a complement tool for the existing prediction methods in this area.  相似文献   

3.
神经网络用于三元分子混合物密度与粘度的预测   总被引:5,自引:3,他引:2  
以二元系实验为基础,利用反向转播算法训练神经网络,构造混合物组成,温度等与物性关系的模型,用于对4个三元混合物体系(1)邻二甲苯-间二甲苯-对二甲苯;(2)四氯化碳-环己烷-2-丙醇;(3)甲醇-丙酮-水;(4)水-甲醇-乙二醇的密度和5个三元混合物体系(1)信甲苯-间二甲苯-对二甲苯;(2)四氯化碳-环己烷-2-丙醇;(3)氯仿-2-丙醇-2-丁醇;(4)甲醇-丙酮-水;(5)乙醇-甲醇-水的粘  相似文献   

4.
An interactive computer program for graphical analysis has been developed by the U.S. Geological Survey. The program embodies five goals, (1) economical use of computer resources, (2) simplicity for user applications, (3) interactive on-line use, (4) minimal core requirements, and (5) portability. It is designed to aid (1) the rapid analysis of point-located data, (2) structural mapping, and (3) estimation of area resources.  相似文献   

5.
The significance of systems configurations has been increased in many applied domains (e.g., software, hardware, manufacturing systems, communication systems, supply chain systems, solving strategies, modular planning, material engineering and combinatorial chemistry). Generally, the following kinds of systems under configuration (reconfiguration) can be examined: (a) initial data/infomation (or row materials); (b) processing systems (machines, computers, algorithms); (c) resultant decisions (e.g., products, plans); (d) applied support systems (e.g., network systems, services); (e) requirements; and (f) standards. In the paper several system configuration problems are investigated: (i) searching for (selection of) a set (structure) of system components, (ii) searching for a set of compatible system components, (iii) allocation of system components, (iv) reconfiguration of a system as redesign of the system structure, (v) multi-stage design and redesign of system configuration, (vi) design or redesign of the system configuration for multi-product systems, and (vii) design of system hierarchy. Combinatorial optimization models (including multicriteria statements) are under examination: multiple choice problem, allocation problem, graph coloring problems, morphological clique problem (with compatibility of system components), multipartite clique and their modifications, spanning trees problems.  相似文献   

6.
Five reconstructed alpha-motoneurons (MNs) are simulated under physiological and morphological realistic parameters. We compare the resulting excitatory postsynaptic potential (EPSP) of models, containing voltage-dependent channels on the dendrites, with the EPSP of a passive MN and an active soma and axon model. In our simulations, we apply three different distribution functions of the voltage-dependent channels on the dendrites: a step function (ST) with uniform spatial dispersion; an exponential decay (ED) function, with proximal to the soma high-density location; and an exponential rise (ER) with distally located conductance density. In all cases, the synaptic inputs are located as a gaussian function on the dendrites. Our simulations lead to eight key observations. (1) The presence of the voltage-dependent channels conductance (g(Active)) in the dendrites is vital for obtaining EPSP peak boosting. (2) The mean EPSP peaks of the ST, ER, and ED distributions are similar when the ranges of G (total conductance) are equal. (3) EPSP peak increases monotonically when the magnitude of g(Na_step) (maximal g(Na) at a particular run) is increased. (4) EPSP kinetics parameters were differentially affected; time integral was decreased monotonically with increased g(Na_step), but the rate of rise (the decay time was not analyzed) does not show clear relations. (5) The total G can be elevated by increasing the number of active dendrites; however, only a small active area of the dendritic tree is sufficient to get the maximal boosting. (6) The sometimes large variations in the parameters values for identical G depend on the g(Na_step) and active dendritic area. (7) High g(Na_step) in a few dendrites is more efficient in amplifying the EPSP peak than low g(Na_step) in many dendrites. (8) The EPSP peak is approximately linear with respect to the MNs' R(N) (input resistance).  相似文献   

7.
NUSH is a block cipher as a candidate for NESSIE. NUSH is analyzed by linear crypt-analysis . The complexity δ = (ε , η) of the attack consists of data complexity ε and time complexity η. Three linear approximations are used to analyze NUSH with 64-bit block. When |K| = 128 bits, the complexities of three attacks are (258, 2124), (260, 278) and (262, 255) respectively. When |K| = 192 bits, the complexities of three attacks are (258, 2157) (260, 2%) and (262, 258) respectively. When |K| = 256 bits, the complexities of three attacks are (258, 2125), (260, 278) and (262, 253) respectively. Three linear approximations are used to analyze NUSH with 128-bit block. When |K|= 128 bits, the complexities of three attacks are (2122, 295), (2124, 257) and (2126, 252) respectively. When |K| = 192 bits, the complexities of three attacks are (2122, 2142), (2124, 275) and (2126, 258) respectively. When |K|= 256 bits, the complexities of three attacks are (2122, 2168), (2124, 281) and (2126, 264) respectively. Two l  相似文献   

8.
This bibliography lists journal publications, conference papers, research technical reports, and articles from trade journals on automated visual inspection for industry which were published during the years from 1981 to 1987. More than 600 references are included. References are organized into 13 categories according to subject matter. The categories are (1) books, (2) conferences and workshops, (3) general discussions and surveys, (4) inspection of printed circuit patterns, (5) inspection of solder joints, (6) inspection of microcircuit photomasks, (7) inspection of integrated circuits and hybrids, (8) inspection of other electrical and electronics components, (9) surface inspection, (10) X-ray inspection, (11) other inspection applications, (12) system components, and (13) inspection algorithms. References listed in each category are arranged in chronological order. The purpose is primarily to provide a complete bibliography for those interested in automated visual inspection. Some general observations have been made for the above areas of activity summarizing the advances that have taken place and the problems that remain to be solved.  相似文献   

9.
The development of injectable integrin α(v)β(3)/α(IIb)β(3) dual antagonists attracts much attention of research for treating of acute ischemic diseases in recent years. In this work, based on a dataset composed of 102 tricyclic piperazine/piperidine furnished dual α(v)β(3) and α(IIb)β(3) antagonists, a variety of in silico modeling approaches including the comparative molecular field analysis (CoMFA), comparative similarity indices analysis (CoMSIA), and molecular docking were applied to reveal the requisite 3D structural features impacting the biological activities. Our statistical results show that the ligand-based 3D-QSAR models for both the α(v)β(3) and α(IIb)β(3) studies exhibited satisfactory internal and external predictability, i.e., for the CoMFA models, results of Q(2)=0.48, R(ncv)(2)=0.87, R(pred)(2)=0.71 for α(v)β(3) and Q(2)=0.50, R(ncv)(2)=0.85, R(pred)(2)=0.72 for α(IIb)β(3) analysis were obtained, and for the CoMSIA ones, the outcomes of Q(2)=0.55, R(ncv)(2)=0.90, R(pred)(2)=0.72 for α(v)β(3) and Q(2)=0.52, R(ncv)(2)=0.88, R(pred)(2)=0.74 for α(IIb)β(3) were achieved respectively. In addition, through a comparison between 3D-QSAR contour maps and docking results, it is revealed that that the most crucial interactions occurring between the tricyclic piperazine/piperidine derivatives and α(v)β(3)/α(IIb)β(3) receptor ligand binding pocket are H-bonding, and the key amino acids impacting the interactions are Arg214, Asn215, Ser123, and Lys253 for α(v)β(3), but Arg214, Asn215, Ser123 and Tyr190 for α(IIb)β(3) receptors, respectively. Halogen-containing groups at position 15 and 16, benzene sulfonamide substituent at position 23, and the replacement of piperazine with 4-aminopiperidine of ring B may increase the α(v)β(3)/α(IIb)β(3) antagonistic activity. The potencies for antagonists to inhibit isolated α(v)β(3) and α(IIb)β(3) are linear correlated, indicating that similar interaction mechanisms may exist for the series of molecules. To our best knowledge this is the first report on 3D-QSAR modeling of these dual α(v)β(3)/α(IIb)β(3) antagonists. The results obtained should provide information for better understanding of the mechanism of antagonism and thus be helpful in design of novel potent dual α(v)β(3)/α(IIb)β(3) antagonists.  相似文献   

10.
Regardless of how organizations measure Internet growth and usage, it is certain that the forces of change that affect the Internet will continue to evolve. in evaluating the economics of competing technologies and determining how organizations can get a return on their technology investments, this article reviews ten technology and consumption trends on the Internet. They are (1) multiple bandwidth delivery, (2) linguistic and cultural diversity, (3) privacy, (4) laws, (5) restricting access, (6) taxation of Internet commerce, (7) information age law enforcement requirements, (8) surviving on a crowded Web, (9) new sources of competition, and (10) information warfare and economic terrorism.  相似文献   

11.
飞行器控制面临的机遇与挑战   总被引:4,自引:0,他引:4  
当前,飞行器控制的发展面临前所未有的机遇与挑战.基于对飞行器的发展趋势、新需求和新技术特征的分析,本文从飞行器新技术特征、信息化环境、无人系统自主性、高可靠可重构容错系统、飞控系统评估与确认五个方面研究和分析了飞行器控制面临的机遇与挑战.为了达到利用机遇和赢得挑战的目标,作者建议加强如下五个方面的研究: 加强面向飞行器新技术特征的飞行器控制概念、理论与方法研究; 加强面向信息化环境的控制、计算与通讯一体化,以及控制、决策与管理一体化的研究; 加强面向不确定性的无人系统高级别自主性的研究; 加强面向高可靠、高安全性的可重构容错飞控系统的研究; 加强面向高效、高可信度的飞控系统评估与确认方法的研究.  相似文献   

12.
介绍了理性筛选流感病毒神经氨酸酶抑制剂的全过程,共分4个阶段:1)化合物数据库类药性处理;2)建立神经氨酸酶抑制剂三维药效团并对目标数据库进行构象搜索;3)分子对接及对接后分析;4)神经氨酸酶抑制模型的建立及待测化合物的活性检测。活性检测后发现4个活性化合物,其中Ic。为10。M的化合物1个.Ic,。为10^-6M的化合物2个,IC50为10^-7M的化合物1个。应用理性筛选方法,从化合物数据库中挑选出部分化合物进行神经氨酸酶抑制活性的筛选,减少了药物筛选的盲目性,提高了药物发现的机率。  相似文献   

13.
《IT Professional》2007,9(2):48-53
Software engineering has developed over the last few decades into a discipline of many diverse areas of interest. Examples include testing, programming, design, architecture, maintenance, metrics and evolution. Specialty conferences and publications proliferate, stay for a short time, and then disappear, while software engineering remains as nontraditional engineering - part craft, part art, and part logic. This article describes 13 challenges faced by software engineering research and practitioner community, and hints on what to do about them. The challenges include: (1) software quality, (2) return on investment, (3) process improvement, (4) metrics and measurement, (5) standards confusion, (6) standards interoperability, (7) legacy software, (8) testing stoppage criteria, (9) interoperability and composability, (10) operational profiles, (11) designing in, (12) product certification, (13) services.  相似文献   

14.
This work deals with the numerical evaluation of the structural response of simply supported (transversally loaded at mid-span) and cantilever (subjected to tip point loads) beams built from a commercial pultruded I-section GFRP profile. In particular, the paper addresses the beam (i) geometrically linear behaviour in service conditions, (ii) local and lateral-torsional buckling behaviour, and (iii) lateral-torsional post-buckling behaviour, including the effect of the load point of application location. The numerical results are obtained by means of (i) novel Generalised Beam Theory (GBT) beam finite element formulations, able to capture the influence of the load point of application, and (ii) shell finite element analyses carried out in the code Abaqus. These numerical results are compared with (i) the experimental values reported and discussed in the companion paper (Part 1) and (ii) values provided by analytical formulae available in the literature.  相似文献   

15.
Book Reviews     
Book review in this Article Margaret Dale & Paul Iles (1992) Assessing Management Skills: A Guide to Competencies and Evaluation Techniques Dean Tjosvold (1991) Team Organization: An Enduring Competitive Advantage Brian Thomas (1992) Total Quality Training: The Quality Culture and Quality Training Michael J. Comer, Patrick M. Ardis, & David Price (1992) Bad Lies in Business, McGraw Hill Rosemary Dinnage (1992) The Ruffian on the Stair Peter Frost and Ralph Stablein (Eds) (1992) Doing Exemplary Research Janet Sayers (1992) Mothering Psychoanalysis, Penguin Books Vivian Walsh, Robin Roy, Margaret Bruce & Stephen Potter (1992) Winning by Design: Technology, Product Design & International Competitiveness David Megginson & Mike Pedler (1992) Self-Development: A Facilitators Guide Linda L. Putnam and Michael E. Roloff (1992) Communication and Negotiation Peter M. Senge (1990) The Fifth Discipline: The Art and Practice of The Learning Organization Keith Bradley (1992) Phone Wars, The Story of Mercury Communications Gordon J. Pearson (1992) The Competitive Organization Sonja A. Sackmann (1991) Cultural Knowledge in Organisations: Exploring the Collective Mind  相似文献   

16.
Semi-tensor product approach to networked evolutionary games   总被引:1,自引:0,他引:1  
In this paper a comprehensive introduction for modeling and control of networked evolutionary games (NEGs) via semi-tensor product (STP) approach is presented. First, we review the mathematical model of an NEG, which consists of three ingredients: network graph, fundamental network game, and strategy updating rule. Three kinds of network graphs are considered, which are i) undirected graph for symmetric games; ii) directed graph for asymmetric games, and iii) d-directed graph for symmetric games with partial neighborhood information. Three kinds of fundamental evolutionary games (FEGs) are discussed, which are i) two strategies and symmetric (S-2); ii) two strategies and asymmetric (A-2); and iii) three strategies and symmetric (S-3). Three strategy updating rules (SUR) are introduced, which are i) Unconditional Imitation (UI); ii) Fermi Rule(FR); iii) Myopic Best Response Adjustment Rule (MBRA). First, we review the fundamental evolutionary equation (FEE) and use it to construct network profile dynamics (NPD)of NEGs.
To show how the dynamics of an NEG can be modeled as a discrete time dynamics within an algebraic state space, the fundamental evolutionary equation (FEE) of each player is discussed. Using FEEs, the network strategy profile dynamics (NSPD) is built by providing efficient algorithms. Finally, we consider three more complicated NEGs: i) NEG with different length historical information, ii) NEG with multi-species, and iii) NEG with time-varying payoffs. In all the cases, formulas are provided to construct the corresponding NSPDs. Using these NSPDs, certain properties are explored. Examples are presented to demonstrate the model constructing method, analysis and control design technique, and to reveal certain dynamic behaviors of NEGs.  相似文献   

17.
A survey of journal articles on neural network business applications published between 1988 and 1995 indicates that an increasing amount of neural network research is being conducted for a diverse range of business activities. The classification of literature by (1) year of publication, (2) application area, (3) problem domain, (4) decision process phase, (5) level of management, (6) level of task interdependence, (7) means of development, (8) corporate/academic interaction in development, (9) technology integration, (10) comparative study, (11) major contribution, and (12) journal provides some insights into the trends in neural networks research. The implications for neural networks developers/researchers and suggestions on future research areas are discussed.  相似文献   

18.
顾冬梅 《自动化学报》1993,19(4):472-476
本文给出了当线性系统的传递函数为区间有理函数时的系统闭环鲁棒稳定性及多项式族δ~1(s)=sum from i=0 to m(Q_i(s)P_i(s))的鲁棒稳定的充要条件。Q_i(s)满足某些假定条件后,得出了δ(s)鲁棒稳定性的有限检验的充要条件。  相似文献   

19.
论文讨论泛逻辑的一级泛运算模型的基本代数性质。证明了T(x,y,h,k)(h∈(0,0.75),k∈(0,1))是幂零的阿基米德型三角范数,T(x,y,h,k)(h∈(0.75,1),k∈(0,1))是严格的阿基米德型三角范数;泛与运算模型与泛蕴涵运算模型形成一个伴随对。当h∈(0,0.75),k∈(0,1)时,有界格(眼0,1演,∨,∧,觹,→,0,1)做成一个MV-代数;当h∈(0.75,1),k∈(0,1)时,有界格(眼0,1演,∨,∧,觹,→,0,1)做成一个乘积代数。进一步,给出了一级泛与运算模型与泛或运算模型的加性生成元与乘性生成元。  相似文献   

20.
用密度泛函理论在B3LYP/LANL2DZ基组水平上对(η~x-C_6H_6)Cr(CO)_n(x=1-6;n=1-5)复合物体系的可能构型进行了自由优化及相互作用能的计算,研究了不同羰基数对复合物稳定性、苯和羰基铬相互作用的影响,并对苯和羰基铬相互作用进行了NBO分析。得到以下结论:(1)当n≤3时,苯与Cr(CO)_n以η~6配位;当n≥4时,苯与Cr(CO)_n以η~2配位;(2)最稳定复合物中随羰基数的增加Cr-C_(benzene)平均键长增长,最大二面角H-C-C-H偏离碳环的角度随复合物对称性降低而逐渐增大;(3)当n为奇数时,复合物相互作用主要表现为苯C-C键的π轨道和Cr-CO键的σ反键轨道;当n为偶数时,复合物相互作用主要表现为苯C-C键的π轨道或π~*轨道与Cr的孤对电子轨道;(4)复合物羰基数越多,最稳定复合物的相互作用能数值越大,稳定性越小。  相似文献   

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