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151.
To ascertain the viability of a project, undertake resource allocation, take part in bidding processes, and other related decisions, modern project management requires forecasting techniques for cost, duration, and performance of a project, not only under normal circumstances, but also under external events that might abruptly change the status quo. We provide a Bayesian framework that provides a global forecast of a project's performance. We aim at predicting the probabilities and impacts of a set of potential scenarios caused by combinations of disruptive events, and using this information to deal with project management issues. To introduce the methodology, we focus on a project's cost, but the ideas equally apply to project duration or performance forecasting. We illustrate our approach with an example based on a real case study involving estimation of the uncertainty in project cost while bidding for a contract. 相似文献
152.
李满清 《湖南人文科技学院学报》2004,(Z1)
青少年心理健康教育不容忽视。由于学习压力大,人际交往空间逼仄,存在着严重的心理问题,耐挫能力差。为此,必须通过学校、家庭、社会和学生自我教育四条途径同时进行。 相似文献
153.
Consider a website and the surfers visiting its pages. A typical issue of interest, for example while monitoring an advertising campaign, concerns whether a specific page has been designed successfully, i.e. is able to attract surfers or address them to other pages within the site. We assume that the surfing behaviour is fully described by the transition probabilities from one page to another, so that a clickstream (sequence of consecutively visited pages) can be viewed as a finite-state-space Markov chain. We then implement a variety of hierarchical prior distributions on the multivariate logits of the transition probabilities and define, for each page, a content effect and a link effect. The former measures the attractiveness of the page due to its contents, while the latter signals its ability to suggest further interesting links within the site. Moreover, we define an additional effect, representing overall page success, which incorporates both effects previously described. Using WinBUGS, we provide estimates and credible intervals for each of the above effects and rank pages accordingly. 相似文献
154.
对理论联系实际学风发展的历史回顾及现实思考 总被引:1,自引:0,他引:1
王曙龙 《延安大学学报(社会科学版)》2007,29(1):72-74
理论联系实际是我们党的优良学风,是马列主义、毛泽东思想、邓小平理论和“三个代表”重要思想一贯坚持的原则。我们党的理论联系实际的优良学风是在党的光辉历程中,在正反两方面经验教训的基础上逐渐形成并发扬光大。大力弘扬理论联系实际的马克思主义优良学风,既是现阶段社会发展的需要,也是党的建设工作客观实际的要求,具有非常重要的实践意义。 相似文献
155.
This article presents a framework for using probabilistic terrorism risk modeling in regulatory analysis. We demonstrate the framework with an example application involving a regulation under consideration, the Western Hemisphere Travel Initiative for the Land Environment, (WHTI‐L). First, we estimate annualized loss from terrorist attacks with the Risk Management Solutions (RMS) Probabilistic Terrorism Model. We then estimate the critical risk reduction, which is the risk‐reducing effectiveness of WHTI‐L needed for its benefit, in terms of reduced terrorism loss in the United States, to exceed its cost. Our analysis indicates that the critical risk reduction depends strongly not only on uncertainties in the terrorism risk level, but also on uncertainty in the cost of regulation and how casualties are monetized. For a terrorism risk level based on the RMS standard risk estimate, the baseline regulatory cost estimate for WHTI‐L, and a range of casualty cost estimates based on the willingness‐to‐pay approach, our estimate for the expected annualized loss from terrorism ranges from $2.7 billion to $5.2 billion. For this range in annualized loss, the critical risk reduction for WHTI‐L ranges from 7% to 13%. Basing results on a lower risk level that results in halving the annualized terrorism loss would double the critical risk reduction (14–26%), and basing the results on a higher risk level that results in a doubling of the annualized terrorism loss would cut the critical risk reduction in half (3.5–6.6%). Ideally, decisions about terrorism security regulations and policies would be informed by true benefit‐cost analyses in which the estimated benefits are compared to costs. Such analyses for terrorism security efforts face substantial impediments stemming from the great uncertainty in the terrorist threat and the very low recurrence interval for large attacks. Several approaches can be used to estimate how a terrorism security program or regulation reduces the distribution of risks it is intended to manage. But, continued research to develop additional tools and data is necessary to support application of these approaches. These include refinement of models and simulations, engagement of subject matter experts, implementation of program evaluation, and estimating the costs of casualties from terrorism events. 相似文献
156.
基于旅西日本游客旅游选择行为的西安旅游市场分析 总被引:1,自引:0,他引:1
根据在全国六大旅游热点城市所做的旅游市场调查的数据结果,对旅西日本游客的旅游选择行为进行了研究,同时进一步有针对性地对西安日本客源市场进行了SWOT分析,在此基础上,对西安旅游业的发展提出了相关对策建议。 相似文献
157.
潜在客户资产测量研究 总被引:1,自引:0,他引:1
客户资产由当前客户资产和潜在客户资产两部分组成,对潜在客户资产测量问题尚未有系统的研究。在客户购买行为建模研究的基础上,提出由客户获取预测分析、客户购买行为分析和客户费用分析组成的潜在客户资产测量方法框架,总结了可用的模型,并用实证案例说明;提出利用当前潜在客户资产分析矩阵分析指导投资和管理决策的方法。 相似文献
158.
杨武云 《西南科技大学学报(哲学社会科学版)》1992,(1)
应用染色体组分析法,对新疆节节麦、黄河流域节节麦、伊朗节节麦和中东节节麦的D染色体组进行了较系统的比较分析,结果表明:新疆节节麦与伊朗、中东两地节节麦在染色体组水平上无明显差异,其差异仅体现在染色体的细微结构组成上;臂内倒位是引起染色体结构组成上细微分化的主要原因。黄河流域节节麦与新疆节节麦的染色体组极为相近;其D组染色体无论在染色体组水平上,还是在染色体细微结构组成上均无差异。本文还就中国节节麦与中国特有六倍体普通小麦的起源演化,中国节节麦种质资源在现代小麦育种中的应用等问题进行了讨论。 相似文献
159.
用三点弯曲(TPB)裂纹试件测定平面应变条件下的断裂韧性J1c与JR,试验结果表明,稀土Ce较大地提高了Al-Mg-Si合金的起裂韧度值J1c,特别是,显著地改善了合金的裂纹扩展抗力JR。金相显微观察和电镜分析表明,稀土Ce改善了材料的初始细观结构(材料在加载前的组织结构),改变了材料的细观损伤特点,发展了材料的含损伤塑性。 相似文献
160.
由于我国水资源空间分布不均匀的突出特点 ,大型跨流域调水工程已经成为我国国民经济可持续发展的重要支撑。文章从水资源的经济特点出发 ,结合南水北调中线工程 ,对水资源跨流域配置的市场供求、成本收益等资源经济学问题进行了分析 ,并对社会主义市场经济条件下水资源跨流域配置的利益分配机制进行了探讨 相似文献