高压气吹除时机对潜艇应急吹除性能的影响分析

高压气吹除主压载水舱是潜艇水下动力抗沉的重要操纵手段之一。由于在高压气吹除主压载水舱的过程中,高压气不同吹除时机对潜艇的运动形式和姿态没有充分的理论研究和计算,导致在实际的高压气吹除主压载水舱过程中高压气吹除时机具有很大的随意性,严重影响潜艇应急吹除的性能。建立高压气吹除模型,运用计算机对艏部和舯部破损工况进行仿真计算并对结果进行分析,得出高压气吹除时机对潜艇能否够成功挽回起着关键性的作用。     

潜艇高压气吹除主压载水舱应急挽回的运动规律和控制策略

针对潜艇高压气吹除压载水舱应急挽回姿态控制难题,以吹除高压气和压载水舱中压力气体为研究对象,推导并构建了高压气吹除和压载水舱解除气压数理模型。结合潜艇应急挽回数学模型,对潜艇发生破损进水事故的应急挽回过程进行数值仿真,分析了某潜艇事故采取3种不同挽回方案条件下潜艇运动姿态变化规律。研究结果表明：所构建的数理模型能较好描述潜艇应急挽回姿态变化规律,为潜艇应急挽回运动规律预报、潜艇运动状态实时评估和姿态控制方案制定提供理论依据和技术支持。     

潜艇应急上浮机动不稳定性建模与仿真

为了避免潜艇在应急上浮过程中,由于较快的上浮速度以及较大的负攻角,水动力呈现强非线性,在横向流作用下潜艇可能产生过大的横倾角甚至失稳倾覆.基于艇体水流入射角和方向角定义下的潜艇非线性水动力描述形式及其试验结果,采用一种新形式的大攻角非稳态潜艇操纵运动仿真数学模型,对高压气吹除主压载水舱后潜艇应急上浮过程的运动状态进行预报.采用拉瓦尔喷管理论对高压气吹除主压载水舱的热力学过程进行建模,并将该过程计算得到潜艇所受的复杂激变力作为潜艇操纵运动仿真数学模型的控制输入,计算结果表明:相较于高压气吹除指数模型,采用的拉瓦尔喷管模型能更为真实地反映实艇高压气吹除过程,对潜艇应急上浮机动的运动状态预报更为准确.应急上浮过程中快速造成较大的尾倾角有利于抑制横倾角的增大,且横倾角主要受水舱吹除顺序的影响,受初始深度的影响较小.根据潜艇事故工况下的初始状态制定有效的高压气应急吹除挽回策略,是抑制应急上浮横倾角的主要手段.     

潜艇动力抗沉运动特性分析

采用潜艇垂直面操纵性运动方程、破损舱进水方程和压载水舱排水方程联立构成的潜艇动力抗沉运动方程,研究了2艘不同吨位潜艇的损管特性和动力抗沉运动,其中动力抗沉运动计算包括单独高压气吹除和高压气吹除加操上浮舵2种情况,并讨论了单独高压气吹除、高压气吹除与操舵联合作用的抗沉效能,从而明确了操舵在动力抗沉中的作用。通过对两艇的仿真计算结果的讨论与分析,并用动力不沉性指数Ka定量地评估了转舵在潜艇动力抗沉中的作用。计算结果表明,潜艇中、首部隔舱破损时,转舵在动力抗沉中效能显著,尾部隔舱破损时效能不明显,甚至作用相反。     

破损潜艇应急起浮操纵控制研究

在建立高压气应急吹除模型的基础上,通过计算机模拟仿真对高压气吹除过程中计算型潜艇应急上浮的主要参数进行计算和分析,给出了艏部破损和舯部破损时操纵安全界限图中的进水限制线,提高了潜艇应急上浮操纵的安全性.     

现代潜艇水下快速吹除技术

本文对当前火药燃气吹除潜艇压载水舱技术在应用方面所表现出的快速吹除的实际效果和存在的问题作了简要的评述,说明了联氨快速吹除技术在现阶段的应用中占有特别重要的地位。同时指出,把更高效能的火药燃气与高压空气联合使用的安全快速吹除措施将是今后开发研究的方向。     

2004年第7期竞答题目

1.一艘客船于晚上9点半启航,9点开始检票上船,但早有人来排队等候上船。假设从第一个乘客到时起,每分钟来的乘客人数一样多。如果开放舷侧的3个入口舱门,则9点9分就不再有人排队;如果开5个入口舱门,则9点5分就没有人排队。问:第一个乘客到达的时间是8点几分?2.压载水舱是船舶上非常重要的一类舱室。船舶正是利用调节压载水舱内装的压载水来改变船的重心高度、吃水深度,改善船的稳性(通俗讲即抗翻船的能力)和耐波性(即船在波浪中平稳航行的能力)。而对于潜艇来说,压载水舱的作用更是举足轻重,控制着潜艇的上浮和下潜。     

潜艇在波浪中潜水与浮起

潜艇在大风浪中航行实施潜水时,由于风浪的影响,会给潜水操纵带来复杂性。大风浪对潜水操纵带来影响主要表现在如下两个方面。一是使主压载水舱注水不均匀而延误潜水时间,并易发生纵横倾。     

基于 AR 模型和SPRT 检验法的过程状态监测

本文利用自适应卡尔曼滤波器原理建立机械系统过程监测模型—AR模型,并根据AR模型系数的变化可以表征系统过程状态这一特点,通过序贯概率比(SPRT)这一假设检验法,对机械系统的运行状况进行判别。实验表明,该方法行之有效,最后,本文给出了实验结果。     

潜艇封舱灭火安全性分析

采用火灾区域模拟的方法建立了潜艇舱室火灾发展模型,并运用Runge-Kutta法对潜艇舱室火灾进行了模拟计算,经分析得出潜艇舱室中的燃烧过程具有缺氧、高温、快速的特点,进而证明了封舱灭火是一项适合于扑灭潜艇火灾的有效措施;然后,从潜艇火灾燃烧极不充分的特点出发,对火灾缺氧过程中产生烟气的主要成分CO的体积百分比进行了简...     

An Unlikely Alliance: Portuguese and South African Airpower in Angola, 1968–1974

The war that Portugal was obliged to fight in Africa began in 1961 and immediately stretched the resources of its armed forces. Nowhere was this thinness more apparent than in policing the vast territory of Angola. The east and southeast of Angola were particularly vulnerable, as the area was a vast, sparsely populated region characterised by enormous featureless plains or chanas covered in tall grass and broken by an extensive river system and mountainous forests. The only military solution to policing these immense spaces was aviation and specifically the helicopter that could carry troops into battle, protect them with a gunship and bring them home when the operation was concluded. The immediate problem for the Portuguese Air Force (Força Aérea Portuguesa or FAP) in Angola and elsewhere was a scarcity of helicopters. The solution was an alliance with South Africa, which had a strong inventory of Alouette IIIs, to help in policing the east. This move was likewise in the interest of South Africa, as its threat came from Zambia through south-eastern Angola. This article examines the strategic and tactical development of this unusual, cross-cultural alliance and the symbiotic relationship that resulted in destruction of the enemies of both in Angola.     

Helping hands: civil–military cooperation and Italy's military operation abroad

In the Post-Bipolar Era the growing complexity of the military operations requires a new approach for the resolution of international crises. Since the end of the Cold War, peace support operations (PSO) have become the mainstay and principal occupation of most Western armies. At the same time, Italy has been one of the most important actors in such an area. The article focuses on the cooperation between military and civil components (a process called CIMIC) as a key variable in the Italian PSOs. We will analyse in detail the main lessons learned from past military interventions as well as the general context in which new tendencies are taking place. The maintaining of a minimum security frame becomes essential to fulfil activities ‘collateral’ to the mission: reconstructing services and infrastructure, food distribution, water and medication, law and order, de-mining, training of local forces, and supporting local institutions. These are the main tasks to obtain thrust and support from the population.     

Terrorism,insurgency, kidnapping,and security in Africa's energy sector

Energy continues to serve as the bedrock of modern economies and the main driver of modern society. For Africa, the production and supply of energy resources such as crude oil, natural gas, uranium, coal, biomass, biofuels and other renewables are an important source of employment, rents, taxes, royalties and profits. This sector brings in several tens of billions of dollars of revenue annually. The production and delivery of such resources, however, depend on critical infrastructures such as pipelines, refineries, processing plants, terminals, rigs, electrical energy pylons, substations, pump stations, vessels, and tankers. These infrastructures have been attacked by terrorists, insurgents, vandals and saboteurs, all of whom see them as targets against which to register their grievances and extract concessions from the state. This paper is a chronological account of some of the documented incidents of terrorism, insurgency, kidnapping, destruction, sabotage, and human casualties suffered in the oil and gas sectors in Africa between 1999 and 2012. It is based on data extracted from the databases of the RAND Database of World Terrorism Incidents and the University of Maryland's Global Terrorism Database (GTD).     

国内外结构钢焊条研究的现状与发展

本文主要介绍了国外焊条的现状和发展趋势,包括焊条的高韧性、高效率、低尘低毒和耐吸潮性能,为国内的焊条研究提供了参考依据。     

A Sign of Victory?: ‘Scottish Swords’ and Other Weapons in the Possession of the ‘Auld Innemie’

Many late medieval documents, notably inventories of arms and armour, of Englishmen contain references to ‘Scottish swords’ and other weapons. What did the compilers of these documents mean when they described a weapon as ‘Scottish’? How did such weapons come to be in the possession of these men? This article will attempt to explain this phenomenon drawing on primary documentary sources and surviving material culture from Glasgow Museums’ collections and others, as well as artworks from the period.     

Tacit support for terrorism: The rapprochement between the USSR and Palestinian guerrilla organizations following the 1967 war

This article demonstrates the inconsistent and wavering Soviet attitude towards national liberation movements in general and the Palestinian organizations in particular. Until the late 1960s, the Soviets viewed these organizations with suspicion, hesitating to engage in political dialogue with them. However, in the 1970s, political and military events in the region, as well as modifications in the Kremlin's Cold War strategies, led to a general shift towards the Middle East in Soviet foreign policy. Soviet leaders showed increased willingness to provide certain Palestinian organizations with arms with which to conduct terrorist activities against Israeli, pro-Israeli, Jewish and Western targets. The article explores the complex relations between Palestinian organizations and the USSR in the field of international terror. The study also exposes and analyzes the nature and content of Soviet–Palestinian arms dialogues and transactions. It provides clear evidence that Soviet policymakers and other luminaries were fully informed of, and sometimes directly involved in, these transactions and dialogues at the highest levels.     

A1 Qaeda and the radical Islamic challenge to western strategy

The September 11 global crisis prompted by the attacks on the World Trade Center and the Pentagon raises major questions concerning the nature and trajectory of terrorism in the post-Cold War global order. Hitherto, terrorism has been largely debated by analysts at the level of nation states. Terrorist and insurgent movements have also been largely anchored in nationalist and ethnic power bases even when they have sought to mobilise a transnational ideological appeal on religious or class grounds. There have been a few exceptions to this pattern such as the alliance between the German Baader-Meinhof group and the Japanese Red Army Faction, but even such international alliances as this did not, until at least the 1980s, presage anything like a global terrorist network necessitating a global strategic response. This study examines terrorism and global strategic responses.     

Helping hands: external support for the KNU insurgency in Burma

This article analyses to what extent the Burmese KNU insurgency made use of external support from states, refugees, and diasporas. Based on extensive fieldwork it is concluded that support from neighbouring states and refugees has for years kept the Karen rebellion alive. Western countries perceived forms of resistance to the illegitimate Burmese regime as just and have therefore played a crucial role in the continuation of conflict in Karen State. It is important that policymakers and donors as well as executing organizations continue to reflect critically on the way they exercise their work.     

Cyberpower in Strategic Affairs: Neither Unthinkable nor Blessed

Abstract

This article explores the effect of connectivity on strategic affairs. It argues that the effect on war's character is potentially, although not yet shown in practice, considerably large. Its effect upon the distribution of power among states in the international system is small, contrary to the claims of ‘cyberwar’ alarmists. All told, however, its effect upon strategic affairs is complex. On the one hand, it represents a significant advance in the ‘complexification’ of state strategies, understood in the sense of the production of intended effects. On the other hand, strategists today – still predominantly concerned with the conflicts and confrontations of states and organised military power – are generally missing the power which non-traditional strategic actors, better adapted to the network flows of the information age, are beginning to deploy. These new forms of organization and coercion will challenge the status quo.