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1.
《全球能源互联网(英文)》2022,5(6):618-626
A novel image sequence-based risk behavior detection method to achieve high-precision risk behavior detection for power maintenance personnel is proposed in this paper. In this method, the original image sequence data is first separated from the foreground and background. Then, the free anchor frame detection method is used in the foreground image to detect the personnel and correct their direction. Finally, human posture nodes are extracted from each frame of the image sequence, which are then used to identify the abnormal behavior of the human. Simulation experiment results demonstrate that the proposed algorithm has significant advantages in terms of the accuracy of human posture node detection and risk behavior identification. 相似文献
2.
Secondary risk in project risk management refers to the risk that arises as a direct result of implementing a risk response action (RRA). It is important for project managers (PMs) to consider the effects caused by the secondary risks in the process of RRA selection. The purpose of this paper is to propose an optimization method to address the problem of selecting risk response actions (RRAs) with consideration of secondary risk which is seldom considered in the existing studies. The optimization model aims to minimize the total risk costs with time constraint being placed on the project makespan. By solving the model, an optimal set of RRAs along with the earliest start time for each activity can both be obtained. The results show that secondary risk plays an important role in the process of RRA selection. Project managers should allocate more budget for responding the project risk when the secondary risk is considered, and consider all factors relating to both time and cost so as to select appropriate RRAs to mitigate primary risk and secondary risk. 相似文献
3.
Bianca B.M. Keers Paul C. van Fenema 《International Journal of Project Management》2018,36(6):861-875
While sourcing by means of Public-Private Partnerships has been lauded over recent years, increasingly risks appear to jeopardise public organisations' unique societal tasks. Integrated Risk Management has not yet been applied to public organisations getting involved in PPP in the sense of understanding risk management capabilities. This article explores risk awareness and risk management practices underpinning maintenance partnership formation by means of a dual case study of two PPP projects and a short industry survey. The results suggest that organisations face several “intolerable risks” linked to project governance and project management responsibilities: insufficient representation of qualified employees, absence of a shared performance system, assignment of responsibilities and decision-making authority, impractical or inappropriate partnership agreement, and timing of the partnership initiative. Cross-case analysis revealed the role of different levels of risk awareness and senior management involvement. Drawing on these findings, a framework for risk management for PPP formation projects is developed. 相似文献
4.
Mohammad Saied Andalib Mehdi Tavakolan Behrouz Gatmiri 《International Journal of Project Management》2018,36(4):600-611
Project valuation, as a decision-making tool for initiating investments in projects, should be able to value project flexibilities and incorporate reasonable risk preferences of relevant decision makers. Real options valuation methods are the available approaches for valuing project flexibilities, whereas they have shortcomings in considering managers’ reasonable risk preferences in project decisions. Therefore, researchers have suggested approximating the perspective on risk of real options methods and practitioners in project management. This study proposes a fair real options valuation for project-based environments by a behavioral economic approach, which adopts binomial lattice method, Monte-Carlo simulation, and cumulative prospect theory. The results show that behavioral factors such as ‘risk attitude’ and ‘loss aversion’ should be accepted in project investment decisions while limited to an acceptable amount depending on the project conditions (e.g. uniqueness of decision-making scenarios). This research contributes to the project management domain by enhancing project investment decisions that include project flexibilities. 相似文献
5.
为有效整治垃圾短信,不断提升不良信息治理的精准性,文章基于XGBoost算法构建了一套科学的分层分级垃圾短信治理体系。通过对用户入网、消费、通信行为等特征进行建模与运算,识别出用户发送垃圾短信的风险系数,并定义了六级用户。分级名单生成后,依托于垃圾短信拦截系统的分级策略管理功能,分别设置相匹配的拦截策略。在加大对中高危用户的识别和拦截力度的同时,有效降低了高价值用户因不良信息治理导致被误拦截的风险。该治理体系应用于辽宁移动管理实际以来,垃圾短信平均投诉量降幅34.82%。误关停投诉率稳定在0.1%以内。一至三级高价值客户群关停投诉量降幅27.43%。 相似文献
6.
Arising out of the challenge for Local Authorities (LAs) to operate sustainable systems of work, is to avoid the creation of ill-health including the most significant causes of physical absence, musculoskeletal disorders (MSDs).The study's aim was to compare the reliability of the manual handling element of the Health and Safety Executives (HSEs) risk comparator tool for different domestic waste collection methods with self-reported pain via body-mapping and MSD ill health absence rates. Participatory body-mapping exercises were carried out in five LAs with one LA resurveyed, six months after the move from 35 and 50 L containers to a wheeled bin recycling service.The lowest levels of self-reported pain were for services designed with 240l wheeled bins excluding glass; the highest levels were for services that included 100l of garden waste sacks and recycling boxes. Industry data supports previous laboratory studies showing wheeled bins to be associated with less MSD outcomes than boxes, baskets and sacks.Triangulation of data established a statistically significant correlation of 0.85 (Pearson) between average pain-count (APC) and the mean MSD absence rates, with a strong correlation of 0.77 (Spearman) between APC and risk rating. The correlation is moderate, 0.49 (Spearman) between MSD absence and risk rating, reflecting possible intervening variables and a low participation rate by LAs.The contribution of this study is to improve the design of sustainable waste collection strategies to minimise MSD associated absence. In the absence of reliable absence data, body mapping should be used as a proxy method of assessing MSD risk. 相似文献
7.
Esperanza González-Redondo 《建筑学研究前沿(英文版)》2022,11(2):255-277
The constructive analysis of Madrid's old timber-framed collective courtyard buildings, whether demolished, preserved intact, or enlarged, has achieved the dating of relevant case studies. New parameters established in this study set a chronology based on front sector original projects: old (1737–1788), pre-modern (1788–1847) and modern (1847–1892). The on-site inspection and archival research point to ongoing misleading construction in the historic Southern area. Some modern corralas erected on top of pre-existing buildings confirm the initial hypothesis. First dimensioning rules for new façades and the stability required in old ones before adding new storeys, maintaining the original masonry or double-layered system, are discovered. Undated buildings suggest their possible origin a la malicia and a later transformation into transitional corralas. Finally, an analysis of the demolished courtyards narrows down the dating and points to new conjectures in some preserved by showing their uneven layout, old features, and structural discordances in each sector. 相似文献
8.
9.
Public-private partnership (PPP) projects have been widely applied in infrastructure construction. A suitable risk distribution strategy is crucial for promoting negotiations between the government and investors. The government usually provides guarantees to investors to distribute risk. However, an excessive guarantee increases the government's financial burden, whereas an insufficient guarantee reduces the confidence of the investors participating in the project. In a minimum revenue guarantee (MRG), the government subsidizes the investors the difference between the actual revenue and the government guarantee line if there is a loss. In PPP power plant and highway projects, investors' revenues come from two sources: government guarantees and the project company's self-sale. To support project companies and to optimize the projects' benefits, the government should set a reasonable benchmark for purchase amounts. Based on the traditional principal-agent model, this paper introduces the reciprocal preference theory to analyze the risk-sharing ratio most suitable for the government. Then, an optimal incentive mechanism is established to guarantee the project's income. The results indicate that by setting a different guarantee strategy for different participants, the government can utilize reciprocal preference to incentivize investors to exert more effort during a partnership and avoid moral hazard. 相似文献
10.
Risk allocation decisions are of critical importance in project management. The present study proposes an explanation for how risk allocation in a contract motivates a contractor to cooperate with a project owner. Theories of risk allocation and trust were used to motivate the research. Using a survey methodology, we collected data concerning 124 construction projects in China. We found that risk allocation influenced the contractor’s role behavior through the contractor’s feeling of being trusted but not the contractor’s trust in the owner. Feeling of being trusted partially mediated the effect of risk allocation on the contractor’s in-role (i.e., contractual) behavior and fully mediated the effect on extra-role behavior. The study introduces a social and psychological view of the impacts of risk allocation to the project and engineering management literature. We contribute to theory by arguing and demonstrating the mediating effect of trust on the relationship between risk allocation and contractor behavior. From a practical standpoint, we conclude that contractual risk allocation has a significant impact on building a trusting relationship between owners and contractors and that contractors who feel trusted perform both contractually mandated actions and actions external to the contract more diligently, resulting in the likelihood of improved outcomes for both parties. 相似文献