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1.
In real-world applications, the k-shortest-paths between a pair of nodes on a network will often be slight variations of one another. This could be a problem for many path-based models, particularly those on capacitated networks where different routing alternatives are needed that are less likely to encounter the same capacity constraints. This paper develops a method to solve for k differentiated paths that are relatively short and yet relatively different from one another, but not necessarily disjoint. Our method utilizes the sum of a path's distance plus some fraction of its shared distance with each other path. A minimax algorithm is used to select the path whose largest sum of length, plus shared length vis-à-vis each previously selected path, is as small as possible. We present computational results for the Chinese railway system, comparing the paths generated by a standard k-shortest-path algorithm with those from our new model.  相似文献   
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As the criterion used by archaeologists for determining early white porcelain is quite ambiguous, the origin of Chinese white porcelain remains a point of disagreement. In this study, we systematically investigate 61 typical Xing porcelains of the late Northern dynasties to the early Sui dynasty (550–600 CE) using spectrophotometer, X-ray fluorescence (XRF), scanning electron microscopy (SEM), and X-ray powder diffraction (XRD), and analyze the differences between early white porcelain and celadon of Xing kiln in terms of their whiteness and raw materials characteristic. The results show that early white porcelain is a new type of ware that differs from celadon, which can be distinguished by whiteness, with a whiteness greater than 8% being early white porcelain and a whiteness less than 8% being celadon. It is assumed that the ancient potters created the whiter wares based on celadon by improving the glaze and selecting new raw materials for the body, but the production of this type of ware was short lived and subsequently refined in the Sui dynasty (581–618 CE) owing to the limited improvement in whiteness.  相似文献   
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徐团辉 《华夏考古》2015,(2):109-115,126
从战国初年的历史形势和韩国的发展战略出发,考虑韩国灭郑的军事策略,结合考古材料,韩国迁都宜阳、阳翟的记载应是可信的。对文献记载的混乱现象应予以全新解读:韩国迁都宜阳、阳翟的时候,平阳作为政治中心在继续使用。换言之,韩国在保持平阳都城地位的同时,迁都宜阳、阳翟,以此来服务灭郑的军事战争。宜阳和阳翟是具有浓厚军事色彩的临时性都城,带有战时陪都的性质。  相似文献   
5.
伪色诺芬《雅典政制》史料价值初探   总被引:1,自引:0,他引:1  
伪色诺芬《雅典政制》作为公元前5世纪后期雅典的历史文献,对于研究雅典政治状况、原提洛同盟"盟邦"与雅典的关系以及探析民主政治的实质具有重要的史料价值。作者主要从平民的权利、海上霸权两个方面论述雅典民主制保持完好的原因,评述"盟邦"主权遭到雅典侵夺的历史事实,从而证明雅典民主制乃是建立在全体雅典人对非雅典人剥削、奴役基础之上的。当政者所采取种种强化民主的措施,其目的都是为了维护雅典人的根本利益。  相似文献   
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《上海博物馆藏战国楚竹书》(七)所收《武王践祚》,实为两种战国"简本"(甲本和乙本)的合抄。传世本则是参考了这两种简本,合编整理而成。与甲本相比,乙本在叙事及文字上更接近于原始的记录,成文应早于甲本。但甲本与乙本之间并没有直接的文本传承关系,应是两系文本发展的不同形态。参照乙本,可以推测《武王践祚》的原初结构,并不包括武王勒铭段。从文献体裁及文章内容看,甲本及传世本的这一段文字,应是合编自其他文献。《武王践祚》三个本子的比较研究显示,早期文献在流传过程中,不仅存在着文字的增饰、丢失与改动等现象,同时还存在着同种文献不同形态的合编整理甚至是不同文献的合并现象。这对我们认识早期文献形成及流传的特殊性,并进而讨论早期文献的史料价值,无疑具有重要的参考意义。  相似文献   
7.
<正>On the snowy highland,the splendid view of mountains and waters vie with each other;the birds and beasts stroll idly as in a courtyard,and the flourishing woods and grasses stretch as far as the eyes can see.Is"Shambhala"a fairyland?Over the years,the central government and Tibet have focused on protecting the highland ecology and have attained impressive achievements.Under the blue sky  相似文献   
8.
《隸續》載《米巫祭酒張普題字》全文,宋洪适對碑文作了綜述,云:"此碑有天師道法及祭酒、鬼兵字,而云受《■經》十二卷,蓋諸張妖黨指傳授之約,頗合史氏所載。"本文對"張普題字"以及該碑所在地作了分析。傳授之約或是祭酒向初入教的道徒傳授道家關於宇宙原始以及長生之道的基本觀念。此碑實是現存罕見的爲後人留下史籍未備的五斗米道入道儀式記録。  相似文献   
9.
Recognition and respect for sexual minorities in Hong Kong is still a contested area. Public sexual identity politics in Hong Kong has been framed by traditional Chinese gender ideology and imported Christian beliefs which are profoundly negative. Focusing on the interpersonal relationships in three spheres of life, the research adopted the sociological perspective of personal life and the feminist geographers’ idea of spatialization of identity management to analyze how the sexual self of sexual minorities has been marginalized and excluded in intimate social spaces of family, church communities and schools in Hong Kong with specific spatial practices and different forms of power/knowledge. By examining overlooked intimate injustice in personal life, this study illustrates that identity conflicts between Christianity and non-heterosexuality in everyday life is constructed through misrepresentation, misrecognition, harassment and exclusion in intimate relationships. Different types of knowledge are being used to reiterate pre-existing norms and institutionalized patterns of cultural value that constitute the sexual minorities as comparatively unworthy of respect. These micro-political processes involve both conformity and resistance to gender and sexual stereotypes. Participants managed to develop spatial coping strategies such as concealment, compartmentalization, confrontation and alternative sources of support to manage their lives with dignity and self-esteem.  相似文献   
10.
In this paper, the Member Discrete Element Method (MDEM) is modified and perfected for three aspects: the algorithm itself, loading and computational efficiency, and to accurately and quantitatively simulate the progressive collapse for large-span spatial steel structures. In addition, the corresponding computational programs are compiled. First, from the perspective of the method, a meshing principle for discrete element models is determined, a treatment for material nonlinearity and strain rate effect is proposed, and a damping model is established. Next, the Displacement Method is introduced to determine the multi-support excitation for the MDEM, and then motion equations of particles under multi-support excitation are derived. On this basis, the specific process of gravitational field loading is presented. Furthermore, parallel implementation strategies for the MDEM based on OpenMP are constructed. Finally, the collapse simulation of a 1/3.5-scaled single-layer reticulated dome shaking table test model under multi-support excitation is carried out. The comparison demonstrates that the ultimate load and failure mode as well as the complete collapse time of the numerical results are consistent with the experimentally measured responses, and the configuration variations from member buckling and local depression until collapse failure are fully captured. Moreover, the displacement time-history curves obtained using MDEM are almost identical to the experimental measurements, and there is a nuance only in the amplitude. It is verified that MDEM is capable of precisely addressing the collapse failure for large-span spatial steel structures. Additionally, the failure mechanism for structures of this type is naturally revealed.  相似文献   
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