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151.
以网上购物系统为例,介绍了Linux系统环境下使用PHP,MySQL开发B2C模式电子商务系统的方法。  相似文献   
152.
Objective: To outline the reasoning behind use of bivalent rLP2086 in a Rhode Island college meningococcal B disease outbreak, highlighting the timeline from outbreak declaration to vaccination clinic, emphasizing that these two time points are <3 days apart. Participants: Staff, faculty, and students at College X eligible for vaccination. Methods: An outbreak response was initiated, advantages/disadvantages of available MenB vaccines were discussed, and a vaccination clinic was coordinated. Results: Bivalent rLP2086 was chosen as the vaccination intervention. We achieved a 94% coverage rate for the first dose. To date, this intervention has prevented further cases of Neisseria meningitidis serogroup B disease at College X. Conclusions: The close, efficient collaboration of public health stakeholders and College X led 94% of the eligible population to be safely vaccinated with at least one dose of bivalent rLP2086. This outbreak marked the first time bivalent rLP2086 was effectively used as an intervention response.  相似文献   
153.
介绍了高校机房排课系统的设计思想和实现方法,重点阐述了系统体系结构的选择、排课算法的实现,并对系统设计中的难点问题给出了具体的解决方案。  相似文献   
154.
基于校园网的高校统计信息系统   总被引:1,自引:0,他引:1  
统计是了解情况、发现问题、制定决策的重要依据。但是 ,由于统计手段、管理等多方面的原因从而导致统计工作的不准确性与低效率。本文探讨了应用信息技术解决统计低效问题的基本思路  相似文献   
155.
The paper is concerned with sequential search on a finite set: an unknown element of the finite set is to be found testing its subsets, and getting the information that the unknown element is or is not an element of the tested subset. The optimum of the strategy lengths is found under the condition that the intersection of any two different test-sets is bounded. This condition is generalized taking the intersection of any m different test-sets instead of two, and the general problem is also solved.  相似文献   
156.
Generalizing methods of constructions of Hadamard group divisible designs due to Bush (1979), some new families of semi-regular or regular group divisible designs are produced. Furthermore, new nonisomorphic solutions for some known group divisible designs are given, together with useful group divisible designs not listed in Clatworthy (1973).  相似文献   
157.
Complete sets of orthogonal F-squares of order n = sp, where g is a prime or prime power and p is a positive integer have been constructed by Hedayat, Raghavarao, and Seiden (1975). Federer (1977) has constructed complete sets of orthogonal F-squares of order n = 4t, where t is a positive integer. We give a general procedure for constructing orthogonal F-squares of order n from an orthogonal array (n, k, s, 2) and an OL(s, t) set, where n is not necessarily a prime or prime power. In particular, we show how to construct sets of orthogonal F-squares of order n = 2sp, where s is a prime or prime power and p is a positive integer. These sets are shown to be near complete and approach complete sets as s and/or p become large. We have also shown how to construct orthogonal arrays by these methods. In addition, the best upper bound on the number t of orthogonal F(n, λ1), F(n, λ2), …, F(n, λ1) squares is given.  相似文献   
158.
Let us denote by (n,k,d)-code, a binary linear code with code length nk information symbols and the minimum distance d. It is well known that the problem of obtaining a binary linear code whose code length n is minimum among (n,k,d)-codes for given integers k and d, is equivalent to solve a linear programming whose solutions correspond to a minimum redundancy error-correcting code. In this paper it will be shown that for some given integers d, there exists no solution of the linear programming except a solution which is obtained using a flat in a finite projective geometry.  相似文献   
159.
Let D(υ, k, λ) be a symmetric design containing a symmetric design D1(υ1, k1, λ1) (k1 < k) and let x = υ1(k ? k1)/(υ ? υ1). We show that k ≥(k1 ? x)2 + λ If equality holds, D1 is called a tight subdesign of D. In the special case, λ1 = λ, the inequality reduces to that of R.C. Bose and S.S. Shrikhande and tight subdesigns then correspond to their notion of Baer subdesigns. The possibilities for (7upsi;, k, λ) designs having Baer subdesigns are investigated.  相似文献   
160.
The norm 6A6 = {tr(A′A)}12 of the alias matrix A of a design can be used as a measure for selecting a design. In this paper, an explicit expression for 6A6 will be given for a balanced fractional 2m factorial design of resolution 2l + 1 which obtained from a simple array with parameters (m; λ0, λ1,…, λm). This array is identical with a balanced array of strength m, m constraints and index set {λ0, λ1,…, λm}. In the class of the designs of resolution V (l = 2) obtained from S-arrays, ones which minimize 6A6 will be presented for any fixed N assemblies satisfying (i) m = 4, 11 ? N ? 16, (ii) m = 5, 16 ? N ? 32, and (iii) m = 6, 22 ? N ? 40.  相似文献   
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