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  • 98年全国大学生数学建模竞赛B题“水灾巡视问题”

    98年全国大学生数学建模竞赛B题“水灾巡视问题”,是一个推销员问题,本题有53个点,所有可能性大约为exp(53),目前没有好方法求出精确解,既然求不出精确解,我们使用模拟退火法求出一个较优解,将所有结点编号为1到53,1到53的排列就是系统的结构,结构的变化规则是:从1到53的排列中随机选取一个子排列,将其反转或将其移至另一处,能量E自然是路径总长度。具体算法描述如下:步1: 设定初始温度T,给定一个初始的巡视路线。步2 :步3 --8循环K次步3:步 4--7循环M次步4:随机选择路线的一段步5:随机确定将选定的路线反转或移动,即两种调整方式:反转、移动。步6:计算代价D,即调整前后的总路程的长度之差步7:按照如下规则确定是否做调整:如果D0,则按照EXP(-D/T)的概率进行调整步8:T*0.9-->T,降温

    标签: 大学生 数学建模 巡视 竞赛

    上传时间: 2015-03-14

    上传用户:himbly

  • java ejb开发 程序4、语句alter table people add(phone_number varchar2(10)) 的作用是 A 修改表结构 B 为people表添加约束

    java ejb开发 程序4、语句alter table people add(phone_number varchar2(10)) 的作用是 A 修改表结构 B 为people表添加约束,约束名称是phone_number C 向people表中添加一列,名称是phone_number,数据类型是varchar2,长度是10 D 上述答案均不正确 5、( )BLOB和CLOB的区别在于 A CLOB只能存放字符类型的数据,而BLOB没有任何限制 B BLOB只能存放字符类型的数据,而CLOB没有任何限制 C CLOB只能存放小于4000字节的数据,而BLOB可以存放大于4000字节的数据 D BLOB只能存放小于4000字节的数据,而CLOB可以存放大于4000字节的数据 6、存储过程从本质上来讲就是 A 匿名的PL/SQL程序块,它可以被赋予参数 B 命名的PL/SQL程序块,它可以被赋予参数 C 命名的PL/SQL程序块,不能被赋予参数 D 匿名的PL/SQL程序块,不能被赋予参数 7、( )下列关于日期数据类型,哪一个语句是正确的写法 A insert into test values( 9999-12-03 ) B insert into test values( 1999-03-02 ) C insert into test values(to_char(1999-06-03, yyyy/dd/mm )) D insert into test

    标签: people phone_number varchar2 alter

    上传时间: 2013-12-26

    上传用户:wendy15

  • 本系统采用A. 系统需求分析报告(设计方法/数据流图/数据字典) B. 数据库的信息要求报告(E—R图及关系数据模型) C. 数据库的操作和应用要求报告(模块结构图<概念结构设计及逻辑结构设计&

    本系统采用A. 系统需求分析报告(设计方法/数据流图/数据字典) B. 数据库的信息要求报告(E—R图及关系数据模型) C. 数据库的操作和应用要求报告(模块结构图<概念结构设计及逻辑结构设计>) D. 调试中出现的问题及解决方法(物理设计,调试及运行,维护) E. 访问数据库的方式(ODBC,

    标签: A. B. C. 报告

    上传时间: 2013-12-27

    上传用户:日光微澜

  • 学生信息查询系统C语言实现 包含的功能有: 1、 系统功能选择菜单:提供了5个功能 A、 按“班级+平均成绩”显示原始数据 B、 输入学号

    学生信息查询系统C语言实现 包含的功能有: 1、 系统功能选择菜单:提供了5个功能 A、 按“班级+平均成绩”显示原始数据 B、 输入学号,显示学生档案,并可选择用顺序查找或者折半查找去实现 C、 输入不完全的学生姓名即可模糊查找学生档案。 D、 输入班级及课程即可统计平均分,优秀率及及格率。 2、 数据显示函数 3、 学号查找函数 4、 模糊查找函数 5、 成绩统计函数

    标签: 信息查询系统 C语言 数据

    上传时间: 2014-08-20

    上传用户:fanboynet

  • See Appendix B for a description of the programs included on this companion disk. RESOURCE.WRI iden

    See Appendix B for a description of the programs included on this companion disk. RESOURCE.WRI identifies other books and resources for Internet programming. WEBHELP.HLP contains an introduction to the World Wide Web. TCPMAN.HLP provides detailed instructions to help you use the Trumpet Winsock included on this disk. Use the Program Manager s File menu Run option to execute the SETUP.EXE program found on this disk. SETUP.EXE will install the programs on your hard drive and create an Internet Programming group window. Internet编程技术 [配套程序] [涉及平台] VC [作者] void [文件大小] 1032K

    标签: description companion Appendix RESOURCE

    上传时间: 2013-12-04

    上传用户:asasasas

  • 加密算法 Test Driver for Crypto++, a C++ Class Library of Cryptographic Primitives: - To generate an

    加密算法 Test Driver for Crypto++, a C++ Class Library of Cryptographic Primitives: - To generate an RSA key cryptest g - To encrypt and decrypt a string using RSA cryptest r - To calculate MD5, SHS, and RIPEMD-160 message digests: cryptest m file - To encrypt and decrypt a string using DES-EDE in CBC mode: cryptest t - To encrypt or decrypt a file cryptest e|d input output - To share a file into shadows: cryptest s <pieces> <pieces-needed> file (make sure file has no extension, if you re running this under DOS) - To reconstruct a file from shadows: cryptest j output file1 file2 [....] - To gzip a file: cryptest z <compression-level> input output - To gunzip a file: cryptest u input output - To run validation tests: cryptest v - To run benchmarks: cryptest b [time for each benchmark in seconds]

    标签: Cryptographic Primitives generate Library

    上传时间: 2015-07-16

    上传用户:wqxstar

  • This project attempts to implement a Database using B+Tree. The project has developed a DATABASE SYS

    This project attempts to implement a Database using B+Tree. The project has developed a DATABASE SYSTEM with lesser memory consumption. Its API includes simple SQL Statements and the output is displayed on the screen. Certain applications for which several features of existing databases like concurrency control, transaction management, security features are not enabled. B+Trees can be used as an index for factor access to the data. Help facility is provided to know the syntax of SQL Statements.

    标签: project implement developed Database

    上传时间: 2013-12-25

    上传用户:semi1981

  • 考察例1 4 - 8中的1 4个点。A中的最近点对为(b,h)

    考察例1 4 - 8中的1 4个点。A中的最近点对为(b,h),其距离约为0 . 3 1 6。B中最近点对为 (f, j),其距离为0 . 3,因此= 0 . 3。当考察 是否存在第三类点时,除d, g, i, l, m 以外 的点均被淘汰,因为它们距分割线x= 1的 距离≥ 。RA ={d, i, m},RB= {g, l},由 于d 和m 的比较区中没有点,只需考察i 即可。i 的比较区中仅含点l。计算i 和l 的距离,发现它小于,因此(i, l) 是最近

    标签:

    上传时间: 2013-12-03

    上传用户:66666

  • Verilog HDL: Magnitude For a vector (a,b), the magnitude representation is the following: A c

    Verilog HDL: Magnitude For a vector (a,b), the magnitude representation is the following: A common approach to implementing these arithmetic functions is to use the Coordinate Rotation Digital Computer (CORDIC) algorithm. The CORDIC algorithm calculates the trigonometric functions of sine, cosine, magnitude, and phase using an iterative process. It is made up of a series of micro-rotations of the vector by a set of predetermined constants, which are powers of two. Using binary arithmetic, this algorithm essentially replaces multipliers with shift and add operations. In a Stratix™ device, it is possible to calculate some of these arithmetic functions directly, without having to implement the CORDIC algorithm.

    标签: representation Magnitude the magnitude

    上传时间: 2013-12-24

    上传用户:金宜

  • About: hamsterdb is a database engine written in ANSI C. It supports a B+Tree index structure, uses

    About: hamsterdb is a database engine written in ANSI C. It supports a B+Tree index structure, uses memory mapped I/O (if available), supports cursors, and can create in-memory databases. Release focus: Major feature enhancements Changes: This release comes with many changes and new features. It can manage multiple databases in one file. A new flag (HAM_LOCK_EXCLUSIVE) places an exclusive lock on the file. hamsterdb was ported to Windows CE, and the Solution file for Visual Studio 2005 now supports builds for x64. Several minor bugs were fixed, performance was improved, and small API changes occurred. Pre-built libraries for Windows (32-bit and 64-bit) are available for download. Author: cruppstahl

    标签: C. hamsterdb structure database

    上传时间: 2013-12-11

    上传用户:LouieWu