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31.
The increase in interconnectivity and developments in technology have caused cyber security to become a universal concern. This paper highlights the dangers of the evolution of cyber risk, the challenges of quantifying the impact of cyber-attacks and the feasibility of the traditional actuarial methodologies for quantifying cyber losses. In this paper, we present a practical roadmap for assessing cyber risk, a roadmap that emphasizes the importance of developing a company and culture-specific risk and resilience model. We develop a structure for a Bayesian network to model the financial loss as a function of the key drivers of risk and resilience. We use qualitative scorecard assessment to determine the level of cyber risk exposure and evaluate the effectiveness of resilience efforts in the organization. We highlight the importance of capitalizing on the knowledge of experts within the organization and discuss methods for aggregating multiple assessments. From an enterprise risk management perspective, impact on value should be the primary concern of managers. This paper uses a value-centric/reputational approach to risk management rather than a regulatory/capital-centric approach to risk.  相似文献   
32.
For option pricing models and heavy-tailed distributions, this study proposes a continuous-time stochastic volatility model based on an arithmetic Brownian motion: a one-parameter extension of the normal stochastic alpha-beta-rho (SABR) model. Using two generalized Bougerol's identities in the literature, the study shows that our model has a closed-form Monte Carlo simulation scheme and that the transition probability for one special case follows Johnson's distribution—a popular heavy-tailed distribution originally proposed without stochastic process. It is argued that the distribution serves as an analytically superior alternative to the normal SABR model because the two distributions are empirically similar.  相似文献   
33.
This research uses a big dataset of online prices published on Booking.com by three-, four- and five-star hotels located in Madrid (Spain). Data is broadened by other sources, resulting in a rich set of context-, hotel- and offer-based variables. This research aims to determine the impact of these variables on the online room prices set by one representative sample, featuring the total pricing behaviour as well as per hotel categories. The variables considered, their extent and the insight per category represent a novelty and complement the literature on demand forecasting and hedonic pricing, enabling the improvement of optimisation techniques. The models, based on regression analysis with random effects, reveal a significant impact of the variables on room prices and a clearly distinct behaviour for five-star hotels. This research contributes to the scientific community and practitioners by showing the pricing dynamics behaviour of an important urban destination by star rating.  相似文献   
34.
公共政策研拟,尤其是环境影响评估,不仅牵涉技术性科学层面,同时涵盖社会性价值评估与政策性决策判断。旨在探讨如何将科学、价值与判断等因素合理融合于环境影响评估作业过程中,并据此研拟一环境影响评估架构,作为中国台湾地区环保部门开发案审核依据之参考。本文所研拟之环境影响评估架构的理论基础包括社会选择理论、社会判断理论及多属性评估方法。通过社会选择理论分析环境政策制定的机制;通过社会判断理论解释科学与价值如何整合于政策制定及其可行性中;而通过多属性评估方法建立开发案评选的集体决策技术。以山坡地开发为例说明此架构在实践中的应用。  相似文献   
35.
36.
Land consolidation plays an important role in increasing cultivated land, improving cultivated land quality and the ecological environment, and promoting the coordinated development of urban and rural areas. However, under the conditions of three decades of land consolidation being conducted and changing urban–rural human–land relationship, the areas of improvement in the land consolidation policy of China must be studied. This article analyzes the implementation and distribution characteristics of the land consolidation project completed in Shaanxi Province in 2018. Results show that land consolidation projects in Shaanxi are mainly land reclamation projects, cropland consolidation projects, and high-standard cropland consolidation projects. The increased cultivated land is mainly from land reclamation projects and cropland consolidation projects. The land consolidation projects in Aeolian Plateau Area, Loess Plateau Area, and Da Ba Mountain Area are mainly land reclamation projects. The land reclamation projects in Guan Zhong Plain Area and Qing Ling Mountain Area account for a large proportion. The spatial distribution of rural settlement consolidation projects, and rural settlement consolidation and land reclamation projects are mainly located in Guan Zhong Plain Area and distributed in the boundary area of Guan Zhong Plain Area and Loess Plateau Area. According to the characteristics of land consolidation projects and the changes of urban–rural human–land relationship, China should be prudent in or stop advancing land reclamation to increase cultivated land; cropland consolidation and high-standard cropland construction are vital ways to achieve China’s food security; and rural settlement consolidation should be carefully conducted in remote areas under the background of urbanization.  相似文献   
37.
Ticket pricing is a key issue for tourism research in China. Owing to regional differences, a unified nationwide price reduction strategy for tourist attractions would be inappropriate for China. To assist in regional ticket pricing decisions, this study uses ArcGIS spatial analysis methods to analyze the spatial differentiation of ticket prices and revenue levels between prefectural units, using 2017 data from 9450 A-grade tourist attractions. The results reveal prominent characteristics of spatial differentiation in tourist attractions’ average ticket prices, as well as in the proportion of their revenue from ticket sales, between prefectural units. Ticket prices are generally low in north China and high in south China; meanwhile, the proportion of ticket revenue is generally high in east China and low in west China. The factors influencing such spatial differentiation are tourism resources, local socio-economic conditions, and the management of tourist attractions. The findings help stakeholders to make differentiation strategy.  相似文献   
38.
研究跨行政区域界面管理问题,对于实现协同目标、提升协同绩效具有重要意义。本文主要研究跨行政区域协同创新界面类型、成因,应对界面障碍策略等问题。结果表明,从协同创新演化及其协同机理来看,跨行政区域主体协同创新界面可以分为内外界面两类;跨行政区域协同创新形成的界面主要有制度、知识、技术、交易、组织和管理等表现形式,起因为界面对应的壁垒。最后提出通过构建协同创新平台来解决跨行政区域协同创新界面障碍的设想,设计了平台形式、结构及其运行机制。  相似文献   
39.
河南省传统村落空间分布特征及影响因素研究   总被引:1,自引:0,他引:1  
[目的]分析河南省传统村落的空间分布特征及其影响因素,以期为中原地区传统村落的建设发展提供指导。[方法]文章通过谷歌地理信息系统及Arc GIS10. 2软件对河南省124个国家级传统村落的空间分布类型、分布格局、分布均衡型及影响因素进行分析,采用最邻近距离法、核密度估计法及地理集中程度等方法揭示其空间分布特征及其形成的影响因素。[结果]最邻近距离法分析R=0. 628,小于1,分布类型为凝聚型。核密度分析中,整体空间分布呈现3个核心区域,平顶山东北区域,豫西北沿省边界呈带状分布及豫南信阳南部,空间分布受地理、经济和文化等因素影响。[结论]河南省传统村落的空间分布属凝聚型不均衡分布。从地级市层面上分析,主要集中在平顶山东部、信阳南部和三门峡地区;从分区层面上,以豫中较多,豫北、豫西和豫南其次,豫东基本空白。形成原因与地理高程、社会经济和历史事件有关。交通不便、经济相对发达或相对落后、历史事件少发的区域,传统村落保存较为完整。  相似文献   
40.
我国灌溉面积位居世界第一,主要矛盾由总量不足转变为结构性矛盾,深入推进供给侧结构性改革提上议程。针对存在的主要结构性矛盾,研究提出系统解决方案,即调整结构、去除库存、提升品质、降低成本、补齐短板。调整结构重点是严格落实"以水定地",着力以水资源、水生态、水环境承载能力倒逼灌溉面积调整;去除库存重点是依法实施"僵尸"工程降等报废,及时办理注销登记;提升品质重点是大力发展高效节水灌溉,提升灌溉服务质量;降低成本重点是深化国有灌区管理体制改革,创新"最后一公里"管理模式;补齐短板重点是坚持统分结合、重点在统的原则推进农田水利产权改革,深化农业水价综合改革,建立准确补贴机制。  相似文献   
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