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1.
《防务技术》2022,18(9):1688-1696
The Al and La elements are added to the Sn9Zn alloy to obtain the fusible alloy for the mitigation devices of solid propellant rocket motors. Differential scanning calorimetry (DSC), metallographic analysis, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), tensile testing and fracture analysis were used to study the effect of Al and La elements on the microstructure, melting characteristics, and mechanical properties of the Sn9Zn alloy. Whether the fusible diaphragm can effectively relieve pressure was investigated by the hydrostatic pressure at high-temperature test. Experimental results show that the melting point of the Sn9Zn-0.8Al0·2La and Sn9Zn–3Al0·2La fusible alloys can meet the predetermined working temperature of ventilation. The mechanical properties of those are more than 35% higher than that of the Sn9Zn alloy at −50 °C–70 °C, and the mechanical strength is reduced by 80% at 175 °C. It is proven by the hydrostatic pressure at high-temperature test that the fusible diaphragm can relieve pressure effectively and can be used for the design of the mitigation devices of solid propellant rocket motors.  相似文献   

2.
none 《Arms and Armour》2013,10(2):114-118
Abstract

The historic displays at the Tower Armouries underwent two significant rearrangements during the nineteenth century. Undertaken by two noted antiquarian scholars, Dr Samuel Meyrick in 1826 and James Robertson Planché in 1868, the underlying circumstances that led up to these developments have not been fully considered; neither has the role played by the Storekeeper’s Department at the Tower in this process. Yet at precisely the same time as these changes were being made the Storekeeper’s Department was becoming more expert in its own collections, acquiring new objects, conducting research, and playing an active part in the scholarly and museological developments of Victorian Britain.  相似文献   

3.
Diversionary theories of war suggest that leaders may engage in bellicose foreign policies to divert the public’s attention from domestic problems and capitalize on a ‘rally around the flag’ type of effect. The evidence regarding diversionary theory is quite mixed. More recently, scholars have focused on situations that create opportunities for diversionary behavior, such as international rivalry and territorial disputes. This paper adds to the growing literature on diversionary conflict by considering the Ethiopia–Eritrea case and applying an opportunity-based approach. We assess whether the Ethiopia–Eritrea War (1998–2000) is consistent with diversionary explanations for the war, as many have previously claimed.  相似文献   

4.
《Arms and Armour》2013,10(1):67-89
Abstract

The main throwing machines invented and used by the Greeks and adopted, more widely, by Roman armies are examined. The kinematics and dynamics of both light and heavy Greek–Roman artillery are used in order to accurately assess its performance. Thus, a better understanding is obtained of the tactics and strategies of the legions of the Roman Empire as well as the reasons for some brilliant campaigns. Reconstructions of a repeating catapult, considered to be the ancestor of the modern machine gun, are also presented. The development of the mechanical design of such machines is discussed and pictorial reconstructions proposed.  相似文献   

5.
This study offers an investigation of the relationship between defense and social spending in the People's Republic of China. In particular, three consecutive questions are answered here. Does a warfare–welfare tradeoff exist in China's budgetary allocation? Is it positive or negative? What is the causal direction involved? By applying a vector autoregression analysis for the period of 1952–2006, this study finds a unidirectional crowd-out effect going from defense to social spending.  相似文献   

6.
The decline in military spending that began in the mid‐1980s continued through 1995, and this decline was widespread both geographically and by level of development. Cuts in military spending appear to have potentially important implications for non‐military spending and fiscal adjustment. In contrast to findings for previous periods, military spending has declined more than proportionately in those countries that have reduced total spending. Countries with Fund programs have reduced military spending more sharply than other developing countries, largely reflecting outcomes in the transition economies. Further, military spending appears to have been less resilient in program countries than other developing countries.  相似文献   

7.
This article examines Egyptian–Soviet relations in the run up to the 1967 Arab–Israeli war. It argues that Egypt and the Soviet Union stumbled into brinkmanship with little coordination and no agreement on common objectives or goals. The article demonstrates how frustration and mutual disappointment were recurring features of the interactions between the two allies during the critical weeks prior to the war. In doing so, the article exposes new aspects of how Cairo and Moscow managed their alliance and assesses what that means to our understanding of the origins of this transformative war. These conclusions challenge revisionist accounts that attribute the start of the war to Egyptian–Soviet collusion and some traditional narratives that present the Soviet Union as an enterprising risk-taker invested in regional brinkmanship. The article draws heavily on Egyptian and Arabic language sources to examine Egyptian–Soviet interactions during this key period of Middle Eastern history.  相似文献   

8.
A cost–benefit analysis of terrorist attacks is developed and placed within a systematic theoretical structure. For the target or object of the attack, we consider the lost value of human lives, lost economic value, and lost influence value, counted as benefits for the terrorist. The corresponding losses for the terrorist are counted as costs. The terrorist attacks if benefits outweigh costs. Bounded rationality is enabled where the three kinds of benefits and costs can be weighted differently. We account for two ex ante probabilities of successful planning and attack, and enable the terrorist to assign different weights to its multiple stakeholders. We introduce multiple time periods, time discounting, attitudes towards risk, and subcategories for the benefits and costs. The cost–benefit analysis is illustrated with the 11 September 2001 attack, and 53 incidents in the Global Terrorism Database yielding both positive and negative expected utilities. The paper is intended as a tool for scientists and policy-makers, as a way of thinking about costs and benefits of terrorist attacks.  相似文献   

9.
This article examines the domestic causes of the Iran–Iraq War. It delves into secret discussions among Iranian political and military elites during the conflict, their analyses of their own performance on the battlefield, and their revealing public disputes and blame game decades later. It contends that an underexplored and yet critical driving force behind Iran’s prosecution of the war was factional politics. Along with state-level geo-strategic, regime-level security and individual-level ideological concerns, factional factors must also be examined to understand Tehran's war-time decisions. Iran’s factional rivalries began between the Islamists and the nationalists; and between the Islamic Revolutionary Guard Corps (IRGC) and the army at war’s outbreak, and eventually penetrated into the heart of the Islamist camp between the militant clerics and the IRGC.  相似文献   

10.
Israel's exceptional status as a nonsignatory to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) has been an increasingly salient issue, particularly during the intense debate over universality in the 1995 NPT Review and Extension Conference, and again following the Indian and Pakistani tests in 1998. This analysis argues that despite these events, Israel's diplomatic position has not weakened significantly in the past decade. The factors that have led to this outcome include changes in the political and strategic environment, including the Iraqi and Iranian NPT violations, and Israeli engagement in different fora such as the Conference on Disarmament (CD) and the United Nations, and in bilateral strategic dialogues with key powers. This report examines whether Israel's exceptional status is likely to be maintained in the face of recent developments in Iran and the precedent set by the U.S.-India nuclear cooperation agreement.  相似文献   

11.
This article examines Kazakhstani nuclear decision making from December 1991 to May 1992. The study is based on unique archival data and reveals how Kazakhstan's policy makers solved a nuclear dilemma that the nation faced in its first years of independence. The article reconstructs the internal policy-making process behind the decision made by President Nursultan Nazarbayev and his circle of advisors to accept non-nuclear status. The author argues that Almaty elaborated a deliberately ambivalent strategy toward the republic's nuclear status with the aim of maximizing the state's strategic interests. The article reviews external pressures affecting Nazarbayev's course of action and discusses policy options articulated during this period.  相似文献   

12.
13.
ABSTRACT

China’s efforts to build a ‘new type of great power relations’ and a ‘new type of military-to-military relations’ do not constitute a major turning point in relations with the United States. Political relations set limits on military cooperation, and the two sides have been unable to construct a sustainable strategic basis for relations. This has contributed to an ‘on-again, off-again’ pattern in military ties. Trends show a pattern of frequent disruptions in military-to-military relations from 2000 to 2010, followed by an increase in interactions beginning in 2012. Nevertheless, obstacles on both sides are likely to limit mutual trust and constrain future development of military-to-military relations.  相似文献   

14.
After a brief survey of the Indian economy, we survey the supply and demand of military expenditures in India over the last four decades. The causes of military expenditures appear to include regional rivalries and protracted conflicts, but it has proven difficult to delineate these with empirical models. The effects of military spending in India on economic growth appear to be benign, despite much speculation to the contrary. However, the opportunity costs of defence spending are shown to be considerable. We conclude with speculation about the role of debt and debt servicing in retarding future economic growth in India. We also speculate about the potential for the creation of a war economy in India.  相似文献   

15.
This study revisits the long run and dynamic causal linkages between defense spending and economic growth in 15 selected European countries for the period 1988–2010 by utilizing recent developments in non-stationary panel data analysis. To this end, the series properties of per capita defense spending, per capita real capita stocks, and per capita real GDP are investigated by the panel unit root tests with and without breaks that support evidence on unit root. The panel cointegration tests with and without breaks are also subsequently employed to investigate whether there exists a long-run equilibrium relationship between these three variables. Finally, our causality analysis from panel vector error-correction model suggests that there is a feedback relation between real capital stock and real GDP in both short and long run, a one-way Granger causality running from real GDP to defense spending in both short and long run, and defense spending only Granger causes real capital stock in the long run.  相似文献   

16.
During World War I the military campaign in Mesopotamia placed enormous demands on local man- and animal power to provide the logistical resources vital to its conduct. This required the British civil and military authorities to construct a wartime state apparatus that filled the administrative vacuum left by the retreating Ottomans and made possible its downward penetration and mobilisation of local resources for the war effort. This article examines the interaction of politics and logistics in Mesopotamia and views the enhanced wartime levels of resource extraction in light of the British attempts to codify their presence in the country after 1918 and the nationalist backlash that resulted.  相似文献   

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19.
This article examines the background to the Royal Navy's acquisition of Polaris. The conventional wisdom is that the Navy had little interest in Polaris, which was foisted on it upon the cancellation of Skybolt. Extensive use of files in the Public Record Office is made to mount the contrary argument, that the Admiralty had been interested in the submarine-launched ballistic missile since at least 1955, that there was widespread support for it among the Naval Staff, that a substantial amount of preparatory work was undertaken with the assistance of the US Navy, and that the naval staff were prepared to accept the deterrent role. Naval tactics – to play a waiting game and feign indifference – have contributed to the establishment of the orthodox interpretation, as has the view that the Navy was handicapped by the lack of a body of doctrine within which the deterrent role could be accommodated. The article shows that the orthodox account cannot be sustained by the evidence, which points to a naval triumph in terms of Whitehall politics and inter-service competition.  相似文献   

20.
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