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191.
This paper serves as a stimulus to investigators to examine the role organizational politics plays in decisions leading to the abandonment of information systems (IS) projects. While prior research has identified the development of IS projects as a highly political process, where stakeholders may be more concerned about furthering their self-interests than about contributing to the overall success of the project, there has been little research on identifying the political factors contributing to IS project abandonment. Our case demonstrates six types of political action that took place that caused an electronic commerce (e-commerce) project to be abandoned. Finally, when analyzing mistakes and their principal causes, there is one important lesson that we should learn. That is, all organizations make mistakes and there is the potential for learning from project abandonment experiences. 相似文献
192.
Keisuke Yoshida;Hiroshi Yajima;Md. Touhidul Islam;Shijun Pan; 《河流研究与利用》2024,40(8):1497-1511
The Amphidromous Ayu (Plecoglossus altivelis), vital for Japan's riverine commercial fisheries, is experiencing population decline due to habitat degradation. In response, Japan is implementing restoration efforts by releasing juvenile fish and cultivating spawning habitats. This study, focusing on the Asahi River's Heidan area, evaluates Ayu spawning habitat suitability, especially in tidal zones, and its conservation implications. Through field surveys and numerical analysis, the research identifies optimal conditions for spawning amid dwindling numbers. Observations from the 2020 peak spawning season showed that water temperatures below 20°C are conducive to spawning, with the best sites producing up to 48,817 eggs/m2. Gravel sizes between 0.85 and 53.0 mm were identified as crucial for effective spawning. Notably, artificial spawning grounds established in 2019 showed no spawning activity, likely due to saline intrusion from tides. Using the three-dimensional hydrodynamic-aquatic ecosystem numerical model, the study assesses flow, substrate, and water quality's impact on spawning, corroborated by sensor data. A key finding is the negative correlation between salinity and egg density in tidal sections of the Asahi River. Furthermore, an artificial intelligence (AI)-based YOLOv5 model, trained on underwater images, effectively detected Ayu aggregations, demonstrating an F1-score of 0.757 in differentiating Ayu from other coexisting fish species in the same aquatic environment. This AI approach provides a nonintrusive method for monitoring Ayu populations and habitat preferences. The research underlines that successful spawning habitats require minimal saline intrusion, with optimal salinity and flow conditions. These insights are critical for spawning ground development, emphasizing the management of tidal effects and riverbed conditions to bolster Ayu populations and preserve aquatic ecosystems. 相似文献
193.
Yu Gong Pan Liu Lei Cheng Guiya Chen Yanlai Zhou Xiaoqi Zhang Weifeng Xu 《Journal of Flood Risk Management》2020,13(1)
The dynamic control of reservoir water level during flood seasons (WLFS) allows a trade‐off between flood control and water resources conservation. In this process, the WLFS dynamic control boundaries are key parameters. The channel flood routing affects the dynamic control operations. However, flood routing is seldom considered in multi‐reservoir aggregation (a popular method for tackling the curse of dimensionality in multi‐reservoir issues). To address this knowledge gap, this study conceptualises channel flood routing as a virtual channel storage reservoir (CSR) based on Muskingum flood routing in the aggregation method. The dynamic control boundaries for the multi‐reservoir WLFS are then derived using the following aggregation‐decomposition method: (a) the aggregation reservoir is created by considering channel storages, and the flood risk is quantified using pre‐discharge rules; and (b) the aggregated reservoir storages are decomposed by maximising hydropower generation with constraints. The Xiluodu, Xiangjiaba and Three Gorges reservoir system on the Yangtze River, China, were selected for a case study. The annual power generation is 175.40 billion kWh when using static operation rules. With dynamic operation, the output would be 177.05 billion kWh if CSRs were not considered and 177.53 billion kWh if CSRs were considered. Thus, the proposed method can efficiently determine the dynamic control boundaries for the multi‐reservoir WLFS. 相似文献
194.
潘峰 《福建金融管理干部学院学报》2012,(1):60-63
讨论式教学有别于传统的讲授式教学。为了达到良好的教学效果,讨论的主题应当紧扣劳动与社会保障法课程内容,能够激发学生的讨论热情,难易适中。在讨论过程中,教师应居于主导地位,有效地控制讨论进程,把握讨论方向,避免偏离讨论主题。讨论结束后,教师要及时总结、评价和补充,对涉及的理论或制度问题进行系统的整理和陈述,以达到讨论式教学的目标。 相似文献
195.
金融危机的演化阶段及其美国检视 总被引:1,自引:1,他引:1
过度自由却缺少监管的资产证券化,最终酿成了美国的次贷危机。次贷危机是一次非传统的金融危机,但可以体现所有金融危机的共同特征,即信用扩张背景下的资产价格泡沫。从资产价格泡沫的形成和发展过程来把握金融危机的生成机理,将有助于我们在把握金融危机本质的基础上极大限度地加以防范。 相似文献
196.
基于金融结构视角的投资与经济稳定 总被引:1,自引:0,他引:1
投资率较高和投资增速较快是导致经济局部过热的主要原因。为此,通过压缩投资规模控制物价并稳定经济增长是当前宏观调控的主旨。而金融已成为资源配置的核心、宏观调控的核心和国家经济安全的核心。在当前压缩投资规模的过程中能否把握好“度”的关键在于支持投资的金融机制与金融结构的完善。本文试图从金融结构角度剖析投资容易波动、难以调控稳定的机理,并在此基础上提出我国金融结构优化的途径。 相似文献
197.
198.
[目的]土壤盐渍化是全球范围内威胁干旱半干旱地区灌溉农业可持续发展的重要问题之一。遥感技术可大范围定性和定量监测和评估土壤盐渍化,为土壤盐渍化防治和治理提供支撑。[方法]文章采用文献计量学方法,对2000—2022年Web of Science核心合集和中国知网数据库收录的土壤盐渍化遥感监测领域相关论文的发文特征、研究热点及其演化趋势进行定量分析,并借助CiteSpace软件进行可视化。[结果](1)国内外基于遥感的土壤盐渍化监测研究总体呈上升态势,中国、美国和德国是土壤盐渍化遥感研究最活跃的国家,中国科学院是最活跃的研究机构,发文量前三的期刊为《Remote Sensing》《Geoderma》和《International Journal of Remote Sensing》;(2)土壤盐渍化遥感监测领域与其他研究领域交叉较为广泛,涉及环境科学、遥感、水资源、电子电气工程等多领域协作,交叉融合趋势显著;(3)机器学习、气候变化、大数据遥感平台是土壤盐渍化遥感研究的热点领域,而土壤盐渍化对植被生长的影响和土壤水盐的交互效应也将成为未来土壤盐渍化遥感的重要研究内容。[结论]该研究结果展示了近20年来土壤盐渍化遥感的发展历程和研究热点,为相关研究挖掘出新研究方向提供了参考。 相似文献
199.
中国要实现从传统农业向现代农业的转型,要走农业规模化、商品化和国际化的道路。本文基于我国农业坚持土地由国家和集体所有的制度安排,对推进适度规模经营的组织形式构建和培育农业劳动力市场等进行探讨。 相似文献
200.
基于在线ADCP,充分发挥河道流量监测的全量程、全自动优势,保障服务防汛抗旱、灌区建设、水利信息化、节水社会建设、三生用水同时,充分服务于宁都当地水环境监测和供水安全保障预警,最大程度落实水功能区生态流量监测和最严格水资源管理,确保水资源节约集约利用率,为高质量发展提供坚强支撑。 相似文献