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1.
Managing risk in infrastructure systems implies dealing with interdependent physical networks and their relationships with the natural and societal contexts. Computational tools are often used to support operational decisions aimed at improving resilience, whereas economics‐related tools tend to be used to address broader societal and policy issues in infrastructure management. We propose an optimization‐based framework for infrastructure resilience analysis that incorporates organizational and socioeconomic aspects into operational problems, allowing to understand relationships between decisions at the policy level (e.g., regulation) and the technical level (e.g., optimal infrastructure restoration). We focus on three issues that arise when integrating such levels. First, optimal restoration strategies driven by financial and operational factors evolve differently compared to those driven by socioeconomic and humanitarian factors. Second, regulatory aspects have a significant impact on recovery dynamics (e.g., effective recovery is most challenging in societies with weak institutions and regulation, where individual interests may compromise societal well‐being). And third, the decision space (i.e., available actions) in postdisaster phases is strongly determined by predisaster decisions (e.g., resource allocation). The proposed optimization framework addresses these issues by using: (1) parametric analyses to test the influence of operational and socioeconomic factors on optimization outcomes, (2) regulatory constraints to model and assess the cost and benefit (for a variety of actors) of enforcing specific policy‐related conditions for the recovery process, and (3) sensitivity analyses to capture the effect of predisaster decisions on recovery. We illustrate our methodology with an example regarding the recovery of interdependent water, power, and gas networks in Shelby County, TN (USA), with exposure to natural hazards.  相似文献   
2.
《Risk analysis》2018,38(1):84-98
The emergence of the complexity characterizing our systems of systems (SoS) requires a reevaluation of the way we model, assess, manage, communicate, and analyze the risk thereto. Current models for risk analysis of emergent complex SoS are insufficient because too often they rely on the same risk functions and models used for single systems. These models commonly fail to incorporate the complexity derived from the networks of interdependencies and interconnectedness (I–I) characterizing SoS. There is a need to reevaluate currently practiced risk analysis to respond to this reality by examining, and thus comprehending, what makes emergent SoS complex. The key to evaluating the risk to SoS lies in understanding the genesis of characterizing I–I of systems manifested through shared states and other essential entities within and among the systems that constitute SoS. The term “essential entities” includes shared decisions, resources, functions, policies, decisionmakers, stakeholders, organizational setups, and others. This undertaking can be accomplished by building on state‐space theory, which is fundamental to systems engineering and process control. This article presents a theoretical and analytical framework for modeling the risk to SoS with two case studies performed with the MITRE Corporation and demonstrates the pivotal contributions made by shared states and other essential entities to modeling and analysis of the risk to complex SoS. A third case study highlights the multifarious representations of SoS, which require harmonizing the risk analysis process currently applied to single systems when applied to complex SoS.  相似文献   
3.
The argument is made for having a positive error culture in child protection to improve decision‐making and risk management. This requires organizations to accept that mistakes are likely and to treat them as opportunities for learning and improving. In contrast, in many organizations, a punitive reaction to errors leads to workers hiding them and developing a defensive approach to their practice with children and families. The safety management literature has shown how human error is generally not simply due to a “bad apple” but made more or less likely by the work context that helps or hinders good performance. Improving safety requires learning about the weaknesses in the organization that contribute to poor performance. To create a learning culture, people need to feel that when they talk about mistakes or weak practice, there will be a constructive response from their organization. One aspect of reducing the blame culture is to develop a shared understanding of how practice will be judged and how those appraising practice will avoid the hindsight bias. To facilitate a positive error culture, a set of risk principles are presented that offer a set of criteria by which practice should be appraised.  相似文献   
4.
Of the three most prominent issues in governance discourse—the horizontal coordination of markets, government hierarchies and networks, global governance and multi-level governance—this paper argues that the last, developing and sustaining structures of multi-level governance, constitutes the most profound governance challenge for most developing countries.The paper identifies the major forces promoting change in favor of multi-level governance in developing countries. Using the growing literature and comparative national experiences (illustrated with the examples of India, the Philippines, Colombia and Nigeria), it highlights the key achievements of democratic decentralization as well as its nagging problems in these countries. Finally, the paper demonstrates the significance of these developments for democracy and development in these countries and shows some of the ways by which external partners—especially experts associated with the Geographic Information Systems for Developing Countries can assist and possibly benefit from this process.  相似文献   
5.
数字水印技术是在数字作品中嵌入不明显的记号。该文分析了印刷品制作中包含数模-模数转换过程的特性,与数字水印技术相结合,将纯数字域的防伪手段应用到模拟领域中的印刷品上。将印刷品扫描打印过程作为失真信道进行建模分析,并在算法中加入预失真;比较了数字水印各算法,结合印刷品的特性采用并改进特征值分解的方法,嵌入和检测有意义水印,通过该水印对二次扫描打印印刷品脆弱不可检测,来达到防伪的要求。该算法相对于空域算法和其他变换域算法有复杂度低、检测准确度高的优势。  相似文献   
6.
This article applies a series of concepts from Niklas Luhmann's systems theory in an analysis of modern welfare organisations. The point of departure is that social help in late modern welfare states has become 'polycentric' in that 'help' is today being defined by various different agents: public, voluntary and private care providers. Empirically, this article investigates re-housing work with homeless people, a kind of social work which involves several different welfare organisations. The case study shows how these organisations define themselves by making internal constructions of their surroundings, and how their self-enclosed nature creates a certain 'insensitivity' towards one another. How to coordinate and translate within this 'polyphony' of incomparable observations and values represents a major managerial challenge for present-day social workers.  相似文献   
7.
We present and justify a propagation algorithm to facilitate the simultaneous calculation, for every node in a probabilistic exper system of the distribution of the associated random quantity, conditional on all the evidence obtained about the remaining nodes.  相似文献   
8.
利用上下解,Brouwer不动点原理及Lyapunov泛函方法,讨论了一类具有反馈控制的Logistic扩散系统的周期解问题;获得了周期解存在且稳定的判别条件.  相似文献   
9.
The paper presents a conceptual review over the main aspects concerning the role of human capital investments and training activities within production processes, followed by empirical evidence on two local economic systems in Northern Italy, based on recent survey data. Theoretical and empirical considerations are brought together in order to provide new insights on the role of training and the factors associated to training activities at firm level.The potential driving factors of training here analysed compounds structural characteristics, labour demand dynamics, human resource management practices, workforce features, and firm performances. We observe that training activities emerge positively associated with high-performance practices, innovative labour demand features, workforce skill level, firm size, and are affected by labour flexibility in various directions. Empirical evidence confirms most previous results but also adds further important insights. The analysis suggests that a widening gap, between few innovatively evolving and many stagnant firms, could characterise the future dynamics of the Region. The high relevance of structural variables, labour demand factors and HRM/innovation practices shows that regional industrial policies and labour policies should be jointly implemented for increasing potential firm productivity. This is a key concern for the current debate on local systems economic development in the European and Italian environment.  相似文献   
10.
本文从工程应用角度出发,综述了目前使用的各种低温外科手术器械的性能特点和适用场合。以当前使用最普遍的LN_2式冷疗仪为例对其原理、结构作了简要说明,着重指出其制造的关键和存在的不足,并对冷疗仪的进一步发展作了展望。  相似文献   
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