城市生态系统常用的评估方法有专家评估法、层次分析法和（）。A、成分分析法B、因果分析

交换式局域网增加网络带宽，改善网络性能的根本原因是 【12】 之间的多对节点的并发连接。

Windows 98采用了虚拟存储技术以扩展可用的内存。在下列文件中，由Windows98创建和管理的、用于扩展内存的交换文件是______。

A．Buffesys

B．Win386.swp

C．Hiberfisys

D．Confisys

In these times when market forces appear increasingly complicated and more volatile, it is all the more important to understand the professional jargon and terminology in the market place in order to be able to better make our investment and business decisions. Understanding key economic indicators will assist in the decision making process, providing a snapshot of the current situation and an insight into the future.
(46) Each economic indicator tells us something about the economy or inflation. Gross Domestic Product (GDP) is probably the most important report as it is the whole framework where other economic indicators fall under.
There are also indicators that are broader tell us about the economy itself rather than the components, e. g. employment figures, leading indicators, money supply figures (M3). Inflation figures, Produce Price Index (PPI) and the Consumer Price Index (CPI) will, in short, inform us of the changes in wholesale prices, cost of consumer (retail) goods and services respectively.
An indicator that is useful must be accurate, timely and reliable. It depends entirely on the integrity of the national statistical system responsible. It is vital to know the accurate components of an indicator. We have to be mindful of the limitation of these statistical figures too.
Some indicators can be historic or extremely volatile, and therefore their values are reduced. It is better to compare the most recent data with earlier months, or take a moving average for the past 3, 6 or 12 months to smooth the data. It will tell us if there has been a significant change in trend and whether a new direction is under way.
Timeliness of an indicator is also significant. (47) Although the reported figures are important, it is crucial to recognize that markets react more to the variance to the consensus forecast than to the absolute change in the indicator. (48) Markets do not like surprises and can be frustrated with volatility upon subsequent revisions to the numbers published, even though significance of the absolute number diminishes with each passing month.
The Index of Leading Economic Indicators (L. E. I) in the US acts as an early warning system, telling us when the economy is about to change direction. (49) This composite index of 11 leading indicators has a good record of providing accurate forecasts. The total index performs better as a prediction tool than any of its parts. This monthly figure is available on the last business day of the month and has low volatility.
(50) As a general rule, turning points in the economy are signaled by three consecutive months of L. E. I changes in the same direction. This leading indicator is like a lighthouse, giving the rest of the world economies a glimpse of the direction of the’ world’s largest economy.

某机电工程公司以EPC方式中标了一化工厂建设工程项目。由于其地处偏僻，规模大，需要较大的临时用电量，并编制了临时用电施工组织设计；考虑工程设备不仅是大件，设备也多，而且需要较多的大型吊装设备，以及施工中高空作业和交叉作业多、工期紧等特点，为确保施工过程中安全生产，公司及项目部结合项目施工现场的实际，针对该工程风险种类多，可能发生多种事故类型，以及存在的重大危险源和危险性较大的重点岗位，编制了生产安全事故应急预案。在应急预案评审中，公司及项目部组织了有关安全、技术、施工管理等专业人员对本项目编制的应急预案进行审定，对涉及本公司、本项目以外的单位或需要地方有关部门配合的，也征得了有关单位和部门同意。最后进行了应急预案培训和演练。为保证工程的顺利实施，项目部每周召开一次协调会，并通报工程施工情况，有效地组织和协调，工作量很大。项目经理部内部沟通协调及时到位，项目进展顺利，从未发生过扯皮、干扰、混乱现象，施工进度、质量、安全、卫生均受到建设单位好评。

在大型吊装作业中，如何协调好吊装设备的使用？

计划是一种事先的安排，用于指导企业实现自已的目标。因此，有助于企业实现目标的前提条件就是（）。

A.制定正确的计划

B.制定灵活的计划

C.制定长期和短期计划

D.不断否定计划