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601.
通过数值处理和计算机模拟,得出一种排布方式的消磁线圈对坦克磁场的影响效应分布,即当消磁线圈为均匀密排情形时,线圈内部为匀强磁场,方向沿通电线圈的轴向,且与环形电流呈右手螺旋关系;线圈外部为磁偶极子场,该场会随着与线圈中心距离的增大而迅速减小。数值模拟的结果可为封闭型军事装备表层安装消磁线圈提供参考;通过分析消磁线圈附加磁场的特点为装备磁防护理论提供一些支持。 相似文献
602.
研究了柱锥级联型爆磁压缩发生器。给出了主要实验结果。发生器的负载是3.5μH,最大电流是55.8KA,上升前沿是14.3μs,电压为30.5KV。平均电流放大倍数是6.4。 相似文献
603.
海流感应电磁场的分析与计算 总被引：6，自引：2，他引：6
根据电磁感应原理对海流感应电磁场进行理论计算,计算结果与有关文献给出的测量结果相一致,这说明文中给出的理论方法是正确的,可用于对海流感应电磁场进行理论估算,为电场和磁场探测设备的设计提供参考数据. 相似文献
604.
含内置式耐压液舱舱段耐压船体结构应力分析 总被引：1，自引：0，他引：1
为研究静压下内置式耐压液舱结构的力学规律,采用有限元方法对内置式耐压液舱及船体结构进行强度计算,分析了不同工况下耐压壳的变形和应力特征,比较了不同区域耐压壳的应力情况。结果表明:液舱内外相连通时的工况更危险,耐压壳应力水平也更高。同时,内置式耐压液舱的存在使液舱底部耐压壳的应力水平高于耐压壳其他区域。该研究结果可为内置式耐压液舱结构设计提供指导。 相似文献
605.
We study an (R, s, S) inventory control policy with stochastic demand, lost sales, zero lead‐time and a target service level to be satisfied. The system is modeled as a discrete time Markov chain for which we present a novel approach to derive exact closed‐form solutions for the limiting distribution of the on‐hand inventory level at the end of a review period, given the reorder level (s) and order‐up‐to level (S). We then establish a relationship between the limiting distributions for adjacent values of the reorder point that is used in an efficient recursive algorithm to determine the optimal parameter values of the (R, s, S) replenishment policy. The algorithm is easy to implement and entails less effort than solving the steady‐state equations for the corresponding Markov model. Point‐of‐use hospital inventory systems share the essential characteristics of the inventory system we model, and a case study using real data from such a system shows that with our approach, optimal policies with significant savings in inventory management effort are easily obtained for a large family of items. 相似文献
606.
Covell Meyskens 《The Nonproliferation Review》2019,26(5-6):499-517
ABSTRACTThis article examines Chinese views of North Korea’s nuclear-weapon program during the Donald J. Trump administration. It shows that China has portrayed itself as a responsible country that promotes regional stability, unlike the United States, which has engaged in military brinkmanship with North Korea. Some Chinese foreign-policy experts have asserted that Beijing should back Pyongyang in the event of war because of their shared history of humiliation by great powers, while others have favored working with other regional partners. Another theme in Chinese discourse about North Korea is that Pyongyang is an impetuous, ungrateful regime that impedes Beijing’s ability to attain its core interests of regional stability, economic development, and heightened global influence. This negative assessment of North Korea drove Beijing’s endorsement of stricter UN sanctions in 2017. While Beijing has punished Pyongyang for its wayward policies, China responded favorably to North Korea’s decision in April 2018 to stop nuclear tests and partake in international dialogue. Beijing seeks to help Pyongyang gradually disarm and develop its economy within a Chinese-led East Asian order. The article concludes by explaining how Beijing’s recent, more positive view of Pyongyang is likely to affect its support for American efforts to dismantle North Korea’s nuclear-weapon program. 相似文献
607.
William Moon 《The Nonproliferation Review》2019,26(5-6):613-634
ABSTRACTAs the United States and North Korea pursue negotiations on a “denuclearization” agreement, the two countries should consider initiating cooperative measures as a way to build confidence and encourage finalization of a complete agreement. Based on lessons from the initial engagements carried out under the Cooperative Threat Reduction (CTR) program in states of the former Soviet Union (FSU), initial cooperation should focus on safety and security, training, and infrastructure elimination. By offering to implement these initiatives now while negotiations are underway, the United States could gain additional insights into North Korean intentions. These early initiatives could be proposed without compromising the US maximum-pressure campaign on North Korea by using the current authorities of the CTR program and carefully designing specific exemptions that may be required for any agreed measures. If North Korea is truly interested in pursuing disarmament efforts, the initial cooperative projects would enable them to begin reaping potential benefits while negotiations continue with sanctions still in place. These initial proposals could also be expanded to include additional international partners such as Russia, China, South Korea, and Japan. Such programs and initiatives would support and supplement longer-term strategies to address North Korean weapons-of-mass-destruction challenges. 相似文献
608.
Mathieu Boulègue 《Defense & Security Analysis》2019,35(1):103-105
The VOSTOK-2018 strategic field training exercise (FTX) that took place in mid-September 2018 rehearsed forces’ integration and combat preparedness across multiple strategic directions. Regarding combat readiness, the research question outlined in this paper relates to whether the General Staff experimented with mission-command - a key component of Russia’s modern military thinking. The answer is clearly no: operational creative manoeuvring hardly featured during the VOSTOK-2018 drills for clearly identified reasons. At the systemic level, little room was left for initiatives since the drills focused on implementing and testing command and control (C2) systems. At the structural level, VOSTOK-2018 was not oriented towards mission-command but ‘mission-control’ and streamlining centralised decision-making processes down to the tactical level. At the symbolic level, free play was not exercised due to the participation of China in the drills, and the necessity to impress Chinese military observers. 相似文献
609.
In the aftermath of 9/11, the USA embarked on a massive global hunt for terrorists and launched its “Operation Enduring Freedom” in Afghanistan. Its failure to control insurgency in Afghanistan spilled over into Pakistan, with disastrous consequences. The resurgence of the Taliban with more formidable tactics and maneuvering skills has become more troublesome for both Afghanistan and Pakistan and for the USA and its allied forces. The fierce comeback of the insurgents has challenged the political and territorial integrity of Pakistan, one that it cannot tolerate. This article analyzes the current situation and its implications for Pakistan's security. Moreover, it looks into the internal and external security complexities that Pakistan faces and the possible implications of the US exit strategy for Pakistan's security. It concludes that the security situation in Pakistan is continuously deteriorating and no part of her territory is immune from terrorists' attacks. To be successful, Pakistan must pursue a broad-based strategy that encompasses military, political, social, economic and informational domains aimed at accomplishing four major objectives: (1) elimination of foreign terrorists and their facilitators; (2) strengthening of the political and administrative institutions in the Federally Administered Tribal Areas (FATA); (3) establishing a safe and secure environment conducive for sustained development and the realization of real socio-economic progress and (4) integrating the FATA into the national mainstream. In the long term, a strategy based on the concept of “Enlightened Moderation” is the right solution, not only to the internal problems of Pakistan but also for the Muslim world and the international community. 相似文献
610.
The paper presents the possibilities of, and methods for, acquiring, analysing and processing optical signals in order to recognise, identify and counteract threats on the contemporary battleground. The main ways electronic warfare is waged in the optical band of the electromagnetic wave spectrum have been formulated, including the acquisition of optical emitter signatures, as well as ultraviolet (UV) and thermal (IR) signatures. The physical parameters and values describing the emission of laser radiation are discussed, including their importance in terms of creating optical signatures. Moreover, it has been shown that in the transformation of optical signals into signatures, only their spectral and temporal parameters can be applied. This was confirmed in experimental part of the paper, which includes our own measurements of spectral and temporal emission characteristics for three types of binocular laser rangefinders. It has been further shown that through simple registration and quick analysis involving comparison of emission time parameters in the case of UV signatures in “solar-blind” band, various events can be identified quickly and faultlessly. The same is true for IR signatures, where the amplitudes of the recorded signal for several wavelengths are compared. This was confirmed experimentally for UV signatures by registering and then analyzing signals from several events during military exercises at a training ground, namely Rocket Propelled Grenade (RPG) launches and explosions after hitting targets, trinitrotoluene (TNT) explosions, firing armour-piercing, fin-stabilised, discarding sabots (APFSDS) or high explosive (HE) projectiles. The final section describes a proposed model database of emitters, created as a result of analysing and transforming the recorded signals into optical signatures. 相似文献