农民收入结构变化对农民种粮积极性的影响——基于粮食主产区与主销区的对比分析

本文基于1993—2017年中国粮食主产区和主销区的面板数据,在比较两个区域农民收入及其结构变化的基础上,使用面板矫正标准误(PCSE)和面板向量自回归(PVAR)模型实证研究并比较主产区和主销区农民收入结构变化对农民种粮积极性的短期和长期影响。结果表明:无论从短期还是从长期来看,对于主产区而言,工资性收入和政策变量对粮播比有显著的负向影响,家庭经营性收入、转移性收入对其有显著正向影响,而财产性收入对其影响不显著。对于主销区而言,家庭经营性收入、转移性收入和财产性收入对粮播比的影响方向与主产区相同,但是工资性收入对其影响与主产区不同,有显著正向影响,政策变量的影响不显著。在长期,工资性收入对主产区和主销区粮播比的影响程度逐渐增加,经营性收入与财产性收入对主产区的影响更大,而转移性收入对主销区的影响更大。因此,在粮食播种面积连续3年下降的背景下,需要进一步优化农业补贴政策,转变粮食生产方式,鼓励主销区增加粮食播种面积,建立多层次农业保险体系。     

欠发达农区农村居民点内部用地结构演变研究

[目的]从农村居民点内部用地结构演变视角,探索中国快速工业化和城镇化进程中的欠发达农区土地利用转型。[方法]以江西省吉安县凤凰镇铺前村为研究区,采用参与式农村评估、GIS与遥感影像相结合的方法复原了1986年、1996年、2006年和2016年农村居民点内部土地利用状况,揭示了农村居民点内部用地数量结构、空间结构和功能结构演变特征。[结果]30年来铺前村农村居民点用地规模先后经历了快速扩张、加速扩张及缓慢扩张3个阶段,用地类型以住宅用地为主,同时出现了一定的多元化发展趋势;农村居民点内部用地空间结构先后呈现蔓延扩张、跳跃式扩张、填隙式扩张模式发展特征;农村居民点内部用地的功能结构演变特征是农业生产功能逐渐弱化,出现微弱的非农生产功能,生活功能虽然经历稳定弱化和加速弱化过程,但是仍是主导功能,生态功能在中后期因内部用地竞争而明显弱化。[结论]通过系统的研究,揭示了30年来铺前村农村居民点内部土地利用结构演变特征,为优化农村土地利用,促进乡村振兴发展提供参考。     

基于三维激光扫描的钢板组合梁结构检测方法

针对钢结构桥梁的传统尺寸检测工作存在数据获取效率低、实地操作困难和检测精度不高等问题,结合三维激光扫描技术,给出一种基于三维激光点云数据的钢板组合梁构件多部位尺寸无损检测方法.主要步骤包括扫描设计、点云获取、点云预处理及配准、截面获取与尺寸检测.以某高速公路桥梁工程钢板组合梁结构检测为例,分别对比了传统尺寸检测方法和本文方法.实验表明该方法具有无接触测量、高可靠性和检测范围全面的优势.     

Corporate sustainability strategies in institutional adversity: Antecedent,outcome, and contingency effects

This study examines (i) how top-level managerial institutional ties drive corporate sustainability strategies of emerging market firms operating under conditions of institutional adversity; (ii) the impact of corporate sustainability strategies on market performance; and (iii) the moderating role of financial resource slack on the relationships between corporate sustainability strategies and market performance. The study builds from institutional development logic and the structure–conduct–performance paradigm. Primary data are collected from 300 firms operating in a major sub-Saharan African market. Findings show that top-level managerial institutional linkages with regulatory national governmental officials, local community leaders, and top managers at other firms drive corporate proactive and responsive sustainability strategies, which in turn influence market performance. In addition, the findings reveal that financial resource slack strengthens the path between corporate proactive sustainability strategies and market performance, but not the path between corporate responsive sustainability strategies and market performance. Theoretical and practical implications are discussed.     

让自然参与设计：一种基于自然演替的 城市自生群落改良设计途径

城市自生群落具有重要的生态服务功能与潜力，但因其外貌不被公众所接受而难以在城市公共空间中应用。将群落生态学和设计学相结合，探索一种介入栽培植物对城市自生群落进行改良，最终形成具有一定美学价值的植物群落的途径。实验以植物群落设计美学原理和种间竞争原理为依据，向已经演替1年的城市自生群落中引入63种栽培植物，按照分层的方式对群落进行改良。3年的观测结果表明，有61.9%的栽培植物可以在城市自生群落中定居并建立优势，能对76.7%的自生植物起到抑制作用，使55.8%的自生植物消失。相比城市自生群落，改良后的群落美观度提高29.4%，公众接受度提高24%，群落的物种丰富度提高至2.29倍。相比一般的人工植物群落，改良后的群落可以节约58.2%的建植成本，降低83.9%的浇水成本和67.8%的除草成本。实验证明改良设计是一种可行的群落设计途径，能有效提高群落的物种丰富度和美学价值，同时让自然参与群落设计过程，实现人与自然的合作。     

组织架构变革推动公司可持续发展影响研究

论文重点分析了企业组织架构变革的动因和变革过程中应该注意的问题,在对案例进行系统剖析研究的基础上,对组织架构变革如何适应并推动公司可持续发展、变革的主要动力、变革的主要策略等方面进行了系统研究,并以此为基础,提出了企业组织架构变革的相关建议。     

A gramscian perspective on field dynamics. The case of the privatization of Italian steel industry

Institutional fields are not static, they undergo times of fragmentation and times of settlement. Neo-institutional research has long explained the settlement of fields as either the effect of political manoeuvring of actors, or of discursive activity influencing cultural codes, narratives and symbols. But can these processes really be considered in isolation? In this paper, we propose to adopt a comprehensive view on fields’ dynamics, one that embraces the interaction of political and discursive manoeuvring to explain how fragmented fields manage to settle. To do so, we build on the Gramscian concept of hegemonic practices as discursive and political processes that integrate cultural equivalence among actors with political alliances based on aligned interests. Hegemonic practices align actors in a new historical bloc (a new settlement). Through this lens, we interpret the case of the Italian State steel privatization (1984–1995) and propose a process model explaining what yields fields’ dynamics from fragmentation to settlement. The model highlights the action of diffused agency in field dynamics, thus overcoming the obsolete challenger/incumbent view, and the need of becoming a historical bloc for alliances to stabilize a field.     

Interbank tiering and money center banks

This paper provides evidence that interbank markets are tiered rather than flat, in the sense that most banks do not lend to each other directly but through money center banks acting as intermediaries. We capture the concept of tiering by developing a core-periphery model, and devise a procedure for fitting the model to real-world networks. Using Bundesbank data on bilateral interbank exposures among 2000 banks from 1999 to 2012, we find strong evidence of tiering in the German banking system. This extent of tiering is unlikely to arise in standard random networks. Indeed, we show that bank specialization and balance sheet variables predict how banks position themselves in the interbank market. This link provides a promising avenue for understanding the formation of financial networks.     

基于MVC的高校OA系统的设计与实现

随着计算机网络的飞速发展，OA系统已是高校信息化建设的重要标志。本文研究了高校信息化办公现状，针对存在的问题，设计并实现了基于B/S体系结构的协同办公系统。系统实现采用了MVC模式。经测试，系统满足设计需求，运行可靠。     

异型阀门质检技术难点分析与建议

通过对长庆油田技术监测中心所检验的异型阀门种类进行统计,结合现有检验装置与工装,对造成异型阀门难以检验的技术难点进行分析,并追溯原因,最后从设计和采购环节提出建议。