贾新光：英国十年运输规划中的公交战略
——摘自搜狐网(http://auto.sohu.com)
2000年7月，英国运输部发表了《英国2000－2010年交通运输发展战略：10年运输规划》（以下简称《规划》）。这个文件全面研究和规划了英国各种交通方式的发展，对我们有很高的参考价值，这里重点分析一下《规划》关于公共交通的内容。
运输发展水平决定生活质量
这份文件指出：“英国的运输战略是，通过改善铁路、公路等各种运输方式，以及国有和私营的运输服务，来克服拥挤与污染。它同时也是一个创建未来繁荣和美好生活环境的投资战略。”
该规划指出：“我们的生活质量好坏取决于运输是否便捷，大多数人们每天必定要出行，即使仅仅是在局部地区。因此我们需要高效率的运输系统来支持经济的繁荣与发展。但是反过来出行方式却给我们的城镇和农村带来了不利影响，由于运输需求的不断增长，我们甚至不适当地改变了全球气候。
规划描述到2010年时运输系统的状况是：
“地方与国家级的现代化、高质量公共运输，人们有更多的旅行选择，且更多的使用公共交通；”
“更多的轻轨系统和富有吸引力的公共汽车服务，通达性良好，跟其它运输方式功能互补，融位一体；”
“高质量的停车场和和便乘配置，以使人不必驾车到拥挤的闹市区去；”
“社区规划、交通连接和土地利用规...
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| Cam Shaft |
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The camshaft is driven by the
crankshaft by one of three methods:
- Gear drive
- Sprockets and timing chain
- Sprockets and timing belt
Camshaft parts. Courtesy of
Ford Motor Corporation.
- Check the camshaft for:
- a plugged oil feed,
- the correct cam lift or
- any broken or severely
worn areas.
- Check each lobe and journal
for:
- scoring,
- scuffing,
- fractured surface,
- pitting,
- and signs of abnormal
wear.
Steel camshaft and roller
followers in good condition.
Badly burned and worn
camshaft bearing bores.
Normal lobe wear is a pattern
slightly off center with a wider wear pattern at the
nose than at the heel. The off-center wear is a
result of the slight taper of the lobe used in
conjunction with the convex shape of the lifter to
rotate the lifter.
Normal wear patterns are
slightly off center on the lobe. Reprinted with the
permission of Ford Motor Company.
- If the wear pattern extends
to the edges of the lobe, the lifter will not
rotate.
- If there is any scoring or
galling, the camshaft will have to be replaced
or reconditioned.
Premature lobe and lifter wear
is generally caused by metal-to-metal contact
between the cam lobe and lifter bottom due to
inadequate lubrication. The nose will be worn from
the cam lobes, and the lifter bottoms will be worn
to a concave shape or may be worn completely away.
This type of failure usually
begins within the first few minutes of operation. It
is the result of insufficient lubrication.
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