2002 66-70
A typical imperative language contains an applicative sub-language which approximate the mathematical abstractions of “timeless” function applied to “spaceless” values, where the acture operation sequences and use of storage space during expression evaluation are organized behind the scenes.
In this setting, values are data structures of low volume, typically a few computer words or less, which means that an illusion of spacelessness can be realized by having intermediate results during expression evaluation stored at the discretion of language implementation, and effecting parameter transmission and assignment operations through value copying.
词汇:
imperative 命令的, 强制的
approximate 近似的,大约的
timeless 永恒的,时间无限的
spaceless 空间无限的
sequence 次序,序列
scene 场景,情景
illusion 幻想,幻觉
evaluation 估价,赋值
discretion 判断力
at the discretion of sth/sb 当/任…自行处理
implementation 执行,(coding)编码
assignment 分配,委派,指定
译文
典型的指令型语言自身具有相应的下层操作语言,下层语言在后台进行任务的组织和表达式求值过程中的空间分配,使得从上层看,程序似乎是在无限的存储空间上进行无限时间的运算。
在这种情形下,数值一般组织成由几个或者更少的计算器字(computer word)组成的底层数据结构。通过在表达式求值过程中缓冲中间结果的办法,以及其它诸如在参数复制中采用值传递以及操作分割等办法,来实现在上层看来空间无限的幻觉。
2002 71-75
Most computer systems are vulnerable to two different groups of attacks: Insider attacks and outsider attacks. A system that is known to be secure to an outsider attack by preventing access from outside can still be vulnerable to the insider attacks accomplished by abusive usage of authorized users. Detecting such abusive usage as well as attacks by outside not only provides information on damage assessment, but also helps to prevent future attacks. These attacks are usually detected by tools referred to as Intrusion Detection Systems.
词汇:
vulnerable 脆弱的,易受攻击的
insider 内行,内部人员
outsider 外行,外部人员
abusive 滥用的,无节制的
authorized 经认定的,经授权的
detect 预防,察觉,检测出
assessment 评估,估算
prevent 预防
intrusion 入侵,闯入
译文:
大多数计算器系统在两种类型攻击下是脆弱的: 一种来自于内部人员,另一种来自于外部。尽管有些系统对于外部的攻击具有良好的防御能力,但是内部合法用户的非法操作同样会对系统造成破坏性攻击。
对系统所受的内外攻击进行检测,不仅仅可以估算攻击造成的伤害,更可以预防未来的攻击。这些攻击通常可以被一些工具检测到,例如”入侵检测系统”。
2001 29
MIMD system can be classified into throughput-oriented systems, high-availability systems and response-oriented systems. The goal of throughput-oriented multiprocessing is to obtain high throughput at minimal computing cost. The techniques employed by multiprocessor operating systems to achieve this goal take advantage of an inherent processing versus input/output balance in the workload to produce balanced and uniform loading of system resources.
词汇:
throughput 生产量,吞吐量
orient 定向
response 响应,应答
employ 雇用,安置
take advantage of 利用
inherent 生来就有的,固有的
versus 对比,比较(缩写为VS, exp China VS Costa Rica)
balance 平衡,平稳,均衡
uniform 统一的,制服
resource 资源
译文:
MIDM系统可以分类为面向生产量系统,面向高性能系统和面向响应系统。面向生产量多处理器系统的目的是耗费最小的处理成本来获取最高的生产量。多处理器系统利用这样的技术来达到上述目的: 用固定的过程替代I/O平衡机制,来使系统资源稳定和有组织。
2001 30
Soon, more of the information we receive via the Internet could come packaged in digital wrappers.
Wrappers are made up of software code that’s targeted to do specific things with the data enclosed within them, such as helping to define queries for search engines. They also keep outsiders from gaining access to that code.
词汇:
via 经由,通过,通路
digital 数字式的,数字的
wrapper 包装
digital wrapper 数字包裹
outsider 外界的
译文:
很快,我们经由Internet收到的更多信息将以数字包裹的形式传递。
数字包裹是由软件代码组成的,目的在于利用封装在里面的数据来完成一些指定的任务,比如为搜索引擎定义查询内容等。同时,它们也拒绝外界对内部数据的非法访问。
2000 14
Network managers have long awaited practical voice-over-IP(VOIP) solutions. VOIP promises ease network management and decreases costs by converging at a company’s telephony and data infrastructures into one network. And a VOIP solution implemented at a company’s headquarters with far-reaching branch offices can save tremendous amounts of money in long distance phone bill, provided that solution delivers POTS-like voice quality over the Internet.
词汇:
practical 实际的,实践的,实用的
converging 聚集,聚会
infrastructure 底层设施,基础设施
implement 贯彻,施行
branch 分支,分枝
译文:
网络管理人员一直期待着实用的声讯IP电话(VOIP)解决方案。通过把一家公司的电话和数据基础设施集成到一个网络服务中去,VOIP能够使网络管理更加方便,并且降底投资。一家使用了VOIP技术且拥有外地分支机构的公司,能够节省大量的长途电话费,并且能够在Internet上以接近于普通电话服务(POTS)的音质进行通话。