Planning Interventions: Urban Bias,Social Reform and the City

The planning profession struggled for urban amelioration, but avoided confronting the conflict between the redistributive public interest and the goals of industrial capital, resulting in a devaluing of social planning in the US. This article classifies social biases in planning and relates them to sanctuary cities. In the current crisis, launched by the federal government’s hostile rhetoric to immigrants, the planning apparatus is forced to confront what it has sought to avoid – planning for the just, inclusive city that has to reckon with the presence of some of the poorest urban populations.     

Assessing Interventions to Reduce the Risk of Campylobacter Prevalence in Broilers

As part of a comprehensive risk assessment on the Campylobacter prevalence in the chicken production chain (from young born chicken till chicken fillet) in the Netherlands, we formulated a quantitative model on the transmission dynamics of Campylobacter at Dutch broiler farms. This model is used to quantify the risk of Campylobacter prevalence in broilers at the time that flocks leave the farm for processing. To this end, we assumed that the Campylobacter prevalence is primarily determined by two parameters, that is, the within- and between-flock transmission. The within-flock transmission was assessed fitting experimental data to a logistic growth model and the between-flock transmission was assessed fitting field data to a generalized linear model (GLM), which included three possible infection routes: (1) via an infected flock in the previous cycle, (2) via other infected flocks present on the farm, and (3) from other sources. This model was applied to assess the efficacy of three control scenarios; (1) a ban on other livestock on broiler farms, (2) a ban on thinning, and (3) a reduction of the between-flock transmission. In contrast to the other scenarios, the third one was shown to be most effective. Theoretically, this is accomplished by improved biosecurity. However, the impact of improved biosecurity cannot be specified into specific control measures, and therefore it is not clear what investments are needed. Finally, we also assessed the efficacy of scheduled treatment, that is, fresh meat production solely from test-negative flocks. We found that the reliability of negative test results, which is crucial, strongly depends on the length of time between testing and slaughter. The sensitivity and specificity of the test appeared to be of minor importance.     

基于连续时间模型的网络视频商业模式选择研究

面对日益增长的网络视频需求,如何选择商业模式,以及如何在不同模式之间进行转换,已经成为网络视频运营商所关注的问题。以网络视频商业模式收费型与免费型为研究对象,考虑用户对视频选择的不确定性和情绪因素,建立连续时间收益模型。利用现代控制理论哈密顿方法,得到收费-免费模式的转换时间点,并确立最优的收费策略和免费策略。研究表明,视频收费价格和嵌入广告量均受视频推出时间和用户体验效用的影响。此外,视频用户对广告的厌恶度也会影响广告嵌入量。研究指出,当网络视频在连续时间内无限期播放时,纯收费模式或纯免费模式为最优策略,即保持单一商业模式可使运营商获利最大。     

Risk Communication for Empowerment: Interventions in a Rohingya Refugee Settlement

There are many reasons that people, when warned of an impending extreme event, do not take proactive, self-defensive action. We focus on one possible reason, which is that, sometimes, people lack a sense of agency or even experience disempowerment, which can lead to passivity. This article takes up one situation where the possibility of disempowerment is salient, that of Rohingya refugees who were evicted from their homes in Myanmar and forced to cross the border into neighboring Bangladesh. In their plight, we see the twin elements of marginalization and displacement acting jointly to produce heightened vulnerability to the risks from extreme weather. Building on a relational model of risk communication, a consortium of researchers and practitioners designed a risk communication training workshop that featured elements of empowerment-based practice. The program was implemented in two refugee camps. Evaluation suggests that the workshop may have had an appreciable effect in increasing participants' sense of agency and hope, while decreasing their level of fatalism. The outcomes were considerably more positive for female than male participants, which has important implications. This work underscores the potential for participatory modes of risk communication to empower the more marginalized, and thus more vulnerable, members of society.     

基于多目标加权灰靶决策模型的节能服务公司选择研究

用能方对节能服务公司（Energy Service Company,ESCO）的选择关系到合同能源管理（Energy Performance Contracting,EPC）能否顺利实施。从用能方的角度,采用灰色系统理论中的多目标加权灰靶决策模型,对存在多决策目标的ESCO选择问题进行研究。通过层次分析法确定ESCO的11个决策目标的决策权数,根据综合效果测度值的比较,最终实现最优对策的选择。本文为用能方的ESCO选择问题提供了一种新的思路。     

Design Improvements for Message Propagation in Malleable Social Networks

This study presents the formal problem definition and computational analysis of the network design improvements for idea and message propagation in both enterprise and consumer social networks (ESN and CSN, respectively). Message propagation in social networks is impacted by how messages are seeded in the network, and by propagation characteristics of the network topology itself. It has been recognized that the propagation properties of these networks can be actively influenced by network design interventions, such as the deliberate creation of new connections. We address the problem of finding cost‐effective message seeding, and identifying potential new network connections that allow improved propagation in social networks with cascade propagation. We use the hop‐constrained minimum spanning tree (HMST) model to find the seeds and possible new connections that result in networks with improved propagation properties. Moreover, we present new heuristic algorithms that substantially improve the solution quality for the HMST problem. Computational results posit that the design improvements proposed by the HMST approach can greatly improve cascade propagation performance of the networks at low cost.     

An Ecological Model for Quantitative Risk Assessment for Schistosomiasis: The Case of a Patchy Environment in the Coastal Tropical Area of Northeastern Brazil

We developed a stochastic model for quantitative risk assessment for the Schistosoma mansoni (SM) parasite, which causes an endemic disease of public concern. The model provides answers in a useful format for public health decisions, uses data and expert opinion, and can be applied to any landscape where the snail Biomphalaria glabrata is the main intermediate host (South and Central America, the Caribbean, and Africa). It incorporates several realistic and case‐specific features: stage‐structured parasite populations, periodic praziquantel (PZQ) drug treatment for humans, density dependence, extreme events (prolonged rainfall), site‐specific sanitation quality, environmental stochasticity, monthly rainfall variation, uncertainty in parameters, and spatial dynamics. We parameterize the model through a real‐world application in the district of Porto de Galinhas (PG), one of the main touristic destinations in Brazil, where previous studies identified four parasite populations within the metapopulation. The results provide a good approximation of the dynamics of the system and are in agreement with our field observations, i.e., the lack of basic infrastructure (sanitation level and health programs) makes PG a suitable habitat for the persistence and growth of a parasite metapopulation. We quantify the risk of SM metapopulation explosion and quasi‐extinction and the time to metapopulation explosion and quasi‐extinction. We evaluate the sensitivity of the results under varying scenarios of future periodic PZQ treatment (based on the Brazilian Ministry of Health's plan) and sanitation quality. We conclude that the plan might be useful to slow SM metapopulation growth but not to control it. Additional investments in better sanitation are necessary.     

Modeling the Airborne Infection Risk of Tuberculosis for a Research Facility in eMalahleni,South Africa

A detailed mathematical modeling framework for the risk of airborne infectious disease transmission in indoor spaces was developed to enable mathematical analysis of experiments conducted at the Airborne Infections Research (AIR) facility, eMalahleni, South Africa. A model was built using this framework to explore possible causes of why an experiment at the AIR facility did not produce expected results. The experiment was conducted at the AIR facility from August 31, 2015 to December 4, 2015, in which the efficacy of upper room germicidal ultraviolet (GUV) irradiation as an environmental control was tested. However, the experiment did not produce the expected outcome of having fewer infections in the test animal room than the control room. The simulation results indicate that dynamic effects, caused by switching the GUV lights, power outages, or introduction of new patients, did not result in the unexpected outcomes. However, a sensitivity analysis highlights that significant uncertainty exists with risk of transmission predictions based on current measurement practices, due to the reliance on large viable literature ranges for parameters.     

网络群体事件政府治理的演化博弈分析

利用演化博弈模型预测舆论的发展趋势,对政府应对网络群体事件采取的治理模式进行了研究.在一般化复制动态模型基础上建立网络群体事件舆论的传播方程,将地方政府部门与弱势群体的策略互动和行为演化融入到传染病传播模型中,用以模拟舆论的扩散和收敛过程.结果表明:在网络群体事件初期,如果弱势群体通过抗争获得政府补偿的概率不断增大,将造成事态的扩大.此时,地方政府应控制信息的交流程度与初始抗争人数,减缓舆论的扩散;在网络群体事件舆论大范围扩散阶段,上级政府介入并采取惩罚措施,及时披露信息,促使网络舆论的收敛平息,实现社会福利最大化.     

Bayesian Hierarchical Structure for Quantifying Population Variability to Inform Probabilistic Health Risk Assessments

Human variability is a very important factor considered in human health risk assessment for protecting sensitive populations from chemical exposure. Traditionally, to account for this variability, an interhuman uncertainty factor is applied to lower the exposure limit. However, using a fixed uncertainty factor rather than probabilistically accounting for human variability can hardly support probabilistic risk assessment advocated by a number of researchers; new methods are needed to probabilistically quantify human population variability. We propose a Bayesian hierarchical model to quantify variability among different populations. This approach jointly characterizes the distribution of risk at background exposure and the sensitivity of response to exposure, which are commonly represented by model parameters. We demonstrate, through both an application to real data and a simulation study, that using the proposed hierarchical structure adequately characterizes variability across different populations.     

Development and Consideration of Global Policies for Managing the Future Risks of Poliovirus Outbreaks: Insights and Lessons Learned Through Modeling

The success of the Global Polio Eradication Initiative promises to bring large benefits, including sustained improvements in quality of life (i.e., cases of paralytic disease and deaths avoided) and costs saved from cessation of vaccination. Obtaining and maintaining these benefits requires that policymakers manage the transition from the current massive use of oral poliovirus vaccine (OPV) to a world without OPV and free of the risks of potential future reintroductions of live polioviruses. This article describes the analytical journey that began in 2001 with a retrospective case study on polio risk management and led to development of dynamic integrated risk, economic, and decision analysis tools to inform global policies for managing the risks of polio. This analytical journey has provided several key insights and lessons learned that will be useful to future analysts involved in similar complex decision-making processes.