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231.
带空气室脉冲水射流系统通用分析法   总被引:1,自引:0,他引:1  
针对所提出的用空气室引发水力共振以增强脉冲水射流的设想,应用水力瞬变特征线解法,建立系统的数学模型,差分网格只取脉冲源、空气室和喷嘴3个边界点,采用变时步法解算。这种方法具有灵活性大、受限制小、便于使用的突出优点。  相似文献   
232.
避雷针保护范围的图形仿真与图解法分析   总被引:1,自引:0,他引:1  
针对避雷针设计过程中计算公式过于复杂的问题,提出了利用平面几何作图求解避雷针联合保护范围的方法,给出了单支、双支和四支避雷针保护范围的作图解题步骤,并利用计算机图形仿真,给出了避雷针保护范围的空间结构图形。  相似文献   
233.
信息错误检测项目的关系分析   总被引:1,自引:0,他引:1  
从提高信息质量这一目标入手,定义了理论信息错误类别空间、可检测信息错误类别空间、检测项目集等基础概念,分析了检测项目集之间的对等、相交、包含和互斥等4种关系及其特点,形成了信息错误检测项目集的2种生成与优化方式,以及若干优化原则,并给出各原则的优先顺序。  相似文献   
234.
在分析我军通用雷达装备质量等级划分的历史情况的基础上,依据装备的实际,从全寿命的观点出发,重点提出了进行质量等级划分和质量等级评定应考虑的要素,指出重新划分质量等级的依据,并首次提出了评定质量等级的数学模型。  相似文献   
235.
办学定位是高等学校确定发展方向、配置资源、形成特色的基本依据,关系到办学的兴衰成败和人才的培养质量,办学定位包含办学目标定位、办学类型定位、办学水平定位、学科性质定位、人才培养定位、办学规模定位、办学特色定位、服务面向定位等内容,高等学校要从社会需求和自身实际出发,切实把握办学定位的原则,科学合理地确定办学定位。  相似文献   
236.
A truly universal ban on anti-personnel mines cannot be realized without engagement of armed non-state actors and armed groups operating outside state control, including rebels and national liberation movements. Events after 9/11 have complicated engagement with organizations that can be classified as ‘terrorists’. Yet, the use of anti-personnel landmines itself can be viewed as an act of terrorism and African leaders have, on various occasions, classified the use of landmines and the presence of unexploded ordnance as engendering insecurity and a serious impediment to development. The success of a total ban ultimately depends upon ensuring that armed non-state actors act in accordance with international humanitarian law. The Geneva Call Deed of Commitment for Adherence to a Total Ban on Anti-Personnel Mines and for Cooperation in Mine Action (DoC) might be described as an alternative instrument to the Anti-Personnel Mine Ban Convention and can serve an important and impartial channel of communication with non-state actors. Already 18 armed groups in Africa have signed the Geneva Call DoC.  相似文献   
237.
I am afraid there is clear evidence that acts of gross misconduct have taken place. This is a shameful thing for the United Nations to have to say, and I am absolutely outraged by it.

—Kofi Annan, United Nations Secretary-General

Despite promulgating a comprehensive set of guidelines to deter UN personnel from committing acts of sexual misconduct, allegations of sexual exploitation and abuse have become widespread within United Nations peacekeeping missions. The policy of zero-tolerance for peacekeeper misconduct has not been matched by strong disciplinary measures, and crimes are often ignored and rarely punished: absentee fathers, rapists and murderers simply disappear back in their home countries. In countries where women and children rarely have the same economic resources, political rights and authority or control over their environment—or their bodies—they easily become prey for those in perceived positions of power and authority. By failing to hold those responsible to account, the UN may in fact be fuelling even greater discrimination and violence against women and children. In order to ensure those who are mandated to protect to do not become perpetrators of abuse, the UN must take a stronger stand against those who commit acts of sexual misconduct, and must ensure that victims see that their abuser is brought to justice and that reparation is offered. A recent report submitted by the Secretary-General's Special Envoy on Sexual Exploitation and Sexual Abuse makes a comprehensive set of recommendations to prevent, detect, and respond to these allegations. The aim of this essay is to highlight some of the main points of the Special Envoy's report, and to examine the practical challenges the UN and troop/police contributing countries will face when attempting to implement these recommendations.  相似文献   
238.
Abstract

A crisis is emerging in the Nile Basin, where some 300 million people in Egypt, Sudan, Ethiopia, Uganda, the Democratic Republic of Congo, Rwanda, Kenya, Tanzania and Burundi rely on the Nile directly or indirectly. Egypt and Sudan wish to preserve a regime based on treaties drawn up during the colonial era that allocated the vast majority of the Nile's water to them. Countries upstream are determined to challenge this. In 1999 the countries using the river formed the Nile Basin Initiative to try to resolve these differences. More than a decade of negotiations failed to break the impasse. In May Ethiopia, Kenya, Rwanda, Tanzania and Uganda decided to wait no longer and signed a new treaty, without the consent of Egypt and Sudan. The signatories have given the other Nile Basin countries one year to join the pact. For Egypt, which relies on the Nile for 95 per cent of its water, this is a question of life or death. Egypt has, in the past, indicated it will go to war if its share of the Nile is reduced. Talks continue, but the impasse is driving the region towards a crisis to which there is no easy resolution.  相似文献   
239.
Defence offsets have often been described as government‐to‐business compensation arrangements or contracts involving “reciprocity beyond that associated with normal market exchange”. This paper argues that it is irrelevant and misleading to use this notion as a criterion for defining offsets.

The paper also explores the apparent inconsistency between the maximising efficiency in defence procurement and the application of offsets requirements. It is shown that defence offsets are a subset of all the price‐quality‐quantity trade‐offs which in general characterise negotiations surrounding complex transactions.

It is argued that although reciprocal or offsetting arrangements are a normal aspect of commercial transacting, the operation of certain offsets schemes namely mandatory offsets obligations, may inhibit the buyer's flexibility in negotiating deals and result in inefficient procurement. This leads us to ask why these offsets schemes have persisted for so long.  相似文献   
240.
This study develops the concepts of fourth generation operations and the associated principles. First, the concept of fourth generation operations is introduced and defined. Fourth generation operations are the evolution and extension of third and fourth generation warfare based on a change of tactics, technology, and combatants. These operations are currently ongoing in Afghanistan and Iraq, and with the global war on terrorism. Based on the framework of US joint doctrine, the supporting principles of fourth generation operations are developed. This requires the introduction of the principle of Population Perception.  相似文献   
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