单选题欲动态地给一个对象添加职责,宜采用______模式。 A.适配器(Adapter) B.桥接(Bridge)C.组合(Composite) D.装饰器(Decorator)
单选题使用_______DPI的分辨率扫描一幅2×4英寸的照片,可以得到一幅300×600象素的图像。
单选题概要设计是软件系统结构的总体设计,以下不属于概要设计的是______。 A.把软件划分为模块 B.确定模块之间的调用关系 C.确定各个模块的功能 D.设计每个模块的伪代码
单选题有算术表达式((a+ b)-c/(d+ e)+f)*(g+ h),其前缀和后缀表达式分别为 (7) 。
单选题以下关于软件质量度量指标的叙述中,说法正确的是______。 A.正确性就是用每千行代码的故障(fault)数来度量 B.软件完整性是指软件功能与需求符合的程度 C.软件维护的工作量比开发阶段的工作量小 D.可用性与用户的操作效率和主观评价有关
单选题某软件项目的活动图如下图所示,其中顶点表示项目里程碑,连接顶点的边表示包含的活 动
单选题在UML类图中,类与类之间存在依赖(Dependency)、关联(Association)、聚合(Aggregation)、组合(Composition)和继承(Inheritance)五种关系,其中,(45)关系表明类之间的相互联系最弱,(46)关系表明类之间的相互联系最强,聚合(Aggregation)的标准UML图形表示是(47)。
单选题某磁盘的转速为7200转分,传输速度为4Mbps,控制器开销为1ms。要保证读或写一个512字节的扇区的平均时间为11.3ms。那么,该磁盘的平均寻道时间最大应不超过{{U}} (25) {{/U}}ms。
单选题设关系R和关系S如下表所示,则关系T是关系R和关系S______的结果。 R A B C S B C D T A a b c b c d a b b f b c e a c a d a d b c d a d d
单选题当一次函数调用发生时,对其执行过程正确描述的是{{U}} (28) {{/U}}。
单选题数据结构中,与所使用的计算机无关的是数据的______结构;链表是一种采用______存储结构存储的线性表,链表适用于______查找,但在链表中进行______操作的效率比在顺序存储结构中进行______操作的效率高;二分法查找______存储结构。
单选题
单选题The Turing machine is an abstract (71) of computer execution and storage introduced in 1936 by Alan Turing to give a mathematically precise definition of (72) . or 'mechanical procedure'. As such it is still widely used in theoretical computer science, especially in (73) theory and the theory of computation. The thesis that states that Turing machines indeed capture the informal notion of effective or mechanical method in logic and mathematics is known as Turing's thesis. Every Turing machine computes a certain (74) partial function over the strings over its alphabet. In that sense it behaves like a computer with a fixed program. However, as Alan luring already described, we can encode the action table of every Turing machine in a string. Thus we might try to construct a Turing machine that expects on its tape a string describing an action table followed by a string describing the input tape, and then computes the tape that the encoded Turing machine would have computed. As Turing showed, such a luring machine is indeed possible and since it is able to simulate any other Turing machine it is called a (75) Turing machine. A universal Turing machine is Turing complete. It can calculate any recursive function, decide any recursive language, and accept any recursively enumerable language. According to the Church-Turing thesis, the problems solvable by a universal Turing machine are exactly those problems solvable by an algorithm or an effective method of computation, for any reasonable definition of those terms.
单选题汉字编码是对每一个汉字按一定的规律用若干个字母、数字、符号表示出来。我国在汉字编码标准化方面取得的突出成就就是信息交换用汉字编码字符集国家标准的制定。收入繁体字的汉字字符集是______。
单选题乔姆斯基(Chomsky)将文法分为4种类型,程序设计语言的大多数语法现象可用其中的( )描述。
单选题以下关于程序设计语言的描述中,正确的是______。
A.在C语言中,对指针变量进行算术运算是没有意义的
B.在C语言中,指针变量必须由动态产生的数据对象来赋值
C.在C语言中,变量和常量都具有类型属性
D.在C语言中,变量和常量都可以被赋值
单选题有可能无限期拥有的知识产权是( )
单选题
单选题以下关于总线的叙述中,不正确的是()。