水平井分段多簇压裂缝间干扰研究

水平井分段多簇压裂在现场得到了广泛运用，其压裂过程中普遍存在缝间干扰现象。缝间干扰有助于形成复 杂裂缝网络以提高储层导流能力，但是也会导致起裂困难，甚至形成砂堵。因此有必要对分段多簇压裂的缝间干扰问 题进行研究。对此，基于弹性力学建立了分析多簇裂缝诱导应力的数学模型，从起裂压力、裂缝宽度、簇间距等多方面 研究了缝间干扰对水平井分段多簇压裂施工的影响。模拟结果显示，诱导应力会导致起裂压力升高、裂缝变窄，严重 时将造成压裂施工失败。通过进行分析，给出了起裂过程及延伸过程中缝间干扰的影响关系。分析认为，利用缝间干 扰提高改造体积时应当控制簇间距防止对压裂施工造成负面影响。研究结论对优化水平井分段多簇压裂设计具有指 导意义。     

Filling the ‘empty space’: Site-specific dance in a techno club

While organisational space has received broad scholarly attention, movement in organisational spaces remains under-researched. This paper introduces the notion of site-specific dance from dance theory to consider the dynamic relationship between space and people, emphasising that movements are a response to a space, its materiality and context. Berghain, in Berlin and one of the world’s most famous techno clubs, is discussed as a case. An interdisciplinary analysis shows how a site-specific performance is created through the interplay of the architecture, the sound and the music organised by the DJ, and the dancing crowd. Methodologically, the dance and performance studies approach develops suggestions for how to analyse movement interaction in organisational space. Reference to dance theory broadens our understanding of how organisational spaces and human interaction enable, produce and negotiate experiences that are transitory, embodied and difficult to pin down.     

民国商业出版与左翼文学潮流的兴起——兼以1930年代良友图书印刷公司的转变为例

将1930年代左翼文学潮流的兴起置于＂民国＂这一社会历史的政治经济研究框架中,可以看到其与民国时期商业出版的经济环境有着十分密切的关系。从此视角出发并结合相关史料,兼以良友图书印刷公司的转变为实例,探寻在与出版业广泛互动的条件下,一度风行文坛进而成为声势浩大＂主潮＂的左翼文学潮流的生成机制。     

A Blueprint for Full Collective Flood Risk Estimation: Demonstration for European River Flooding

Floods are a natural hazard evolving in space and time according to meteorological and river basin dynamics, so that a single flood event can affect different regions over the event duration. This physical mechanism introduces spatio‐temporal relationships between flood records and losses at different locations over a given time window that should be taken into account for an effective assessment of the collective flood risk. However, since extreme floods are rare events, the limited number of historical records usually prevents a reliable frequency analysis. To overcome this limit, we move from the analysis of extreme events to the modeling of continuous stream flow records preserving spatio‐temporal correlation structures of the entire process, and making a more efficient use of the information provided by continuous flow records. The approach is based on the dynamic copula framework, which allows for splitting the modeling of spatio‐temporal properties by coupling suitable time series models accounting for temporal dynamics, and multivariate distributions describing spatial dependence. The model is applied to 490 stream flow sequences recorded across 10 of the largest river basins in central and eastern Europe (Danube, Rhine, Elbe, Oder, Waser, Meuse, Rhone, Seine, Loire, and Garonne). Using available proxy data to quantify local flood exposure and vulnerability, we show that the temporal dependence exerts a key role in reproducing interannual persistence, and thus magnitude and frequency of annual proxy flood losses aggregated at a basin‐wide scale, while copulas allow the preservation of the spatial dependence of losses at weekly and annual time scales.     

Winnicott’s “Potential Space” and the Jewish Study Hall for social work students,faculty and practitioners

Abstract

The article addresses the potential interface and dialogue between academic and quasi-academic spaces. In particular, it examines the space of the Jewish Study Hall (Beit Midrash) as facilitative of the professional as well as personal development of social work students and practitioners in an Israeli college. We examine how Winnicott’s potential space concept contributes to understanding the Study Hall’s uniqueness as an extracurricular learning space within the School of Social Work. Twenty participants in the Beit Midrash for Judaism and Social Work took part in the study. Thematic analysis of transcribed sessions revealed three themes: (1) The Beit Midrash as a peaceful, safe and inclusive physical space; (2) The Beit Midrash as a space for playing out different realities; and (3) The Beit Midrash as contributing to social work training. Findings indicate that potential spaces that embrace the metaphysical world can help students engaged in religion and spirituality to complement and expand their academic training. We conclude by recommending that Winnicottian potential spaces that embrace the metaphysical world be integrated in social work programmes.     

学习迁移的系统理论:PPEE理论模型的建构和意义

学习是人类社会永恒的主题。为了更好地利用过去的经验，增强学习效果，个人和组织进行学习迁移具有重要意义。学习迁移是指将在以往通过学习或解决问题所获得的经验，用于解决之后所遇到的问题。本文力图建立系统的学习迁移理论，研究人、问题、环境的因素对于学习迁移的影响。本文采用理论推导的研究方法，在前人研究的基础上，提出相应的理论模型。本文运用系统的观点，构建了学习迁移的PPEE理论模型，认为人的因素、问题的因素、人和问题的交互作用、以及环境的调节作用，会共同影响学习迁移的效果。本理论主要从五个方面论述学习迁移的机制。首先，将人的因素按照不同层面划分为后端基本能力、中端心理过程、前端知识结构，讨论了其各自对学习迁移效果的直接影响。其次，将问题的因素划分为形象相似性和抽象相似性，并根据这两个维度构建了四种问题间关系类型，并探究了其与学习迁移效果之间的关系。第三，同时考虑人的因素和问题的因素，研究了二者之间的互动对于学习迁移效果的影响。第四，将环境因素划分为时间紧迫性和空间重要性两个维度，探讨了人和环境，以及问题和环境之间的互动对学习迁移效果的影响。第五，基于系统整体的方面，研究人、问题、环境三者之间的互动对学习迁移效果的交互影响。本文还认为，该模型不仅适用于个人，也同样适用于团队、组织、地区、甚至国家和社会等各个层面，影响各个层面主体的学习迁移。本文最后总结了研究的理论和实践贡献，并提出了未来研究课题。本文对丰富学习理论、特别是学习迁移理论，以及推动教育和管理实践的发展进步具有重要的意义。     

中国拆船业的发展对策

随着国际拆船业持续繁荣,拆船大国之间的竞争越来越激烈。如何促进中国拆船业的发展,提升其国际竞争力成为亟待解决的问题。首先阐述中国拆船业的发展历程,然后对影响中国拆船业发展的因素进行分析,并运用状态空间模型预测未来两年世界和中国拆船业的发展状况,进而提出促进中国拆船业健康发展的相关建议。     

Comparison of procedures for fitting the autoregressive order of a vector error correction model

This paper investigates the lag length selection problem of a vector error correction model by using a convergent information criterion and tools based on the Box–Pierce methodology recently proposed in the literature. The performances of these approaches for selecting the optimal lag length are compared via Monte Carlo experiments. The effects of misspecified deterministic trend or cointegrating rank on the lag length selection are studied. Noting that processes often exhibit nonlinearities, the cases of iid and conditionally heteroscedastic errors will be considered. Strategies that can avoid misleading situations are proposed.     

Joint product assortment,inventory and price optimization to attract loyal and non-loyal customers

In this paper, we analyze the emerging retail practice of carrying a combined product assortment consisting of both regular “standard” products and more fashionable and short-lived “special” products. The purpose of this practice is to increase store traffic by attracting heterogeneous classes of customers, which drives up sales of standard products due to the potential cross-selling effect. Customers who are primarily attracted by special products will also buy some standard products. In this context, we analyze three decisions that are crucial for a retailer׳s commercial success: the product assortment, the inventory levels and the pricing. We propose an optimization model and an iterative heuristic to analyze the trade-offs between the combined product assortment, the inventory level and the price per product when there is limited shelf space. Using numerical experiments, we show that our heuristic can be trusted and that its accuracy improves when the number of products increases. Our findings indicate that to attract more customers for standard products, a retailer may benefit from carrying low priced special products which, if considered in isolation, would be non-profitable. As the cross-selling effect decreases, a retailer should focus more on the standard assortment by increasing its size and decreasing the prices. However, introducing special products and ignoring the cross-selling effect may decrease a retailer׳s profitability. We show that the introduction of special products involves more than just choosing the right specials for non-loyal customers but impacts the global assortment planning, the standard products and the products pricing.     

“管他”的语法化

＂管他＂是一个至今未被收入虚词词典的连词性成分。在现代汉语中,＂管他＂虽然没有词汇化为一个词,但它是一个经过句法上的并入操作而实现的韵律词,比＂管＂更有资格充当连词性成分。＂管他＂语法化为连词性成分首先是语义条件,即＂管＂由行为动词演变为心理动词、代词＂他＂的意义虚化,其次是语音条件,即现代汉语双音节的自然音步模式。此外,＂管他＂语法化为连词的直接语境是反问句,相关语境是否定句。