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近期,欧洲东部的白俄罗斯和中亚的吉尔吉斯斯坦出现剧烈政治动荡,位于南高加索地区的阿塞拜疆和亚美尼亚发生了严重的军事冲突。后苏联空间国家的新动向看似偶然,但细细观察,则不难发现某些规律。这是多种力量共同作用的结果,也充分体现了相关国家的转型之难。 相似文献
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<正>纵观人类文明史,名为"气候变化"的幽灵,时常徘徊在战火硝烟之间。进入21世纪,气候变化与国家安全的联系更紧密了吗?不可否认,海平面上升、干旱和土壤退化,正将食物和居所等生活必需品置于危险境地。今年10月,美国国防部再度重申,气候变化是"威胁倍增器",由此衍生的对资源的争夺"会加剧一国内外的压力源,如贫困、环境恶化、政治不稳定和社会紧张,从而催生恐怖活动和其他形式的暴力"。 相似文献
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Multi-satellite observation integrated scheduling method oriented to emergency tasks and common tasks 总被引:1,自引:0,他引:1 下载免费PDF全文
Satellite observation scheduling plays a significant role in improving the efficiency of satellite observation systems.Although many scheduling algorithms have been proposed,emergency tasks,characterized as importance and urgency(e.g.,observation tasks orienting to the earthquake area and military conflict area),have not been taken into account yet.Therefore,it is crucial to investigate the satellite integrated scheduling methods,which focus on meeting the requirements of emergency tasks while maximizing the profit of common tasks.Firstly,a pretreatment approach is proposed,which eliminates conflicts among emergency tasks and allocates all tasks with a potential time-window to related orbits of satellites.Secondly,a mathematical model and an acyclic directed graph model are constructed.Thirdly,a hybrid ant colony optimization method mixed with iteration local search(ACO-ILS) is established to solve the problem.Moreover,to guarantee all solutions satisfying the emergency task requirement constraints,a constraint repair method is presented.Extensive experimental simulations show that the proposed integrated scheduling method is superior to two-phased scheduling methods,the performance of ACO-ILS is greatly improved in both evolution speed and solution quality by iteration local search,and ACO-ILS outperforms both genetic algorithm and simulated annealing algorithm. 相似文献
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朝鲜半岛西部海域的延坪岛、隅岛、白翎岛、大青岛及小青岛,被称为"西海五岛"。1953年《朝鲜停战协定》对于海上的分界划分表述相对模糊,为此后朝韩在该区域的冲突埋下了伏笔。进入21世纪以来,这片海域成为朝韩之间分歧最大且最容易诱发军事冲突的区域。白翎岛:指向北方的大炮依然矗立2014年秋天,我从韩国仁川港上船,历时大约四个小时的海上颠簸,登上了白翎岛。 相似文献
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最近一段时间,随着中美关系持续下行,加之美国大选的不确定性,国内外不断传出类似“美国要轰炸甚至占领中国南海岛礁”的所谓内部消息,中美双方的前沿兵力也都在强化存在和威慑,在此背景下,社会各界纷纷担心,继贸易战和科技战后,“中美会不会爆发军事冲突”? 相似文献
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