Using quantitative influence diagrams to map natural resource managers’ mental models of invasive species management

Despite the significant effect that invasive species have on natural values, the number and extent of invasions continue to rise globally. At least three dominant reasons explain why policy development and implementation can fail: differences in managers’ mental models of invasive species management; cross-agency responsibility; and poor planning and management (i.e., planning–implementation gap). We used a case study of cross-agency management of gamba grass (Andropogon gayanus) in Australia to explore the differences in organizational staffs’ mental models of management. The gamba grass invasion in northern Australia is continuing to expand and associated effects are increasing; coordinated action across agencies is needed to manage the expansion. Our aim was to examine how staff would represent their mental models as a diagram that we could compare between individuals and groups. We used cognitive mapping techniques to elicit models of 15 individuals from across 5 organizations, represented as an influence diagram, which shows the interrelationships that define a system. We compiled the individual influence diagrams to create a team model of management that captures the common connections across participants’ diagrams. The team model revealed that education, science, legislation, enforcement and property management plans were perceived to be the most important management tools to control or eradicate gamba grass. The Weed Management Branch was perceived to have the most central role in gamba grass management, while other organizations were perceived to have specific roles according to their core business. Significant positive correlations (i.e., shared perceptions) were observed across half of the participants, indicating that the some participants have shared models that could be used as a starting point for discussing the team model, clarifying roles and responsibilities, and potentially building consensus around a shared model. Dominant opportunities for improvement identified by participants were better use of management tools, namely education and enforcement, better coordination and collaboration between agencies and increased resourcing. Our research demonstrates the value and validity of using influence diagrams to explore managers’ mental models and to create a team model that could serve as a starting point for improved cross-agency natural resource management.     

Wildlife viewing: The impact of money-back guarantees

Wildlife sightings are not always guaranteed. To address this risk, tour operators often offer a money-back guarantee as a refund mechanism. However, studies have overlooked the influences of such refund mechanisms on tourists' tour participation decisions and tourism revenue. We conducted choice experiments to examine the impact of such mechanisms using a case of Amami rabbit tourism in Japan. We found that the guarantee significantly influences the tourists’ decision-making and tour revenue. In particular, we found that the expected tourist participation rate and tour guide revenue vary drastically depending on the probability of the rabbit encounter. The maximum expected revenue from the tour with a 90% chance was about 20 times larger than that with a 10% chance. This indicates that conserving wildlife to maintain the sighting probability raises tour benefits, creating a win-win situation by balancing conservation and tourism development.     

焦化厂深化厂务公开工作情况的调研报告

厂务公开是企业民主管理工作的重要组成部分。近年来,焦化厂通过推行厂务公开民主管理工作,实现了从厂部到车间及至班组的三级网络公开体系,形成了常规性工作定期公开,长期性、阶段性工作分阶段公开,短期、临时性工作随时公开的良好态势。使职工的知情权、参与权和监督得到有效的落实,为现代企业发展提供了强有力的支撑。     

OPTIPRO系统在发电厂中的综合运用

本文介绍了OPTIPRO系统在发电厂中的综合运用,主要介绍了运行操作指导和设备状态监视方面的方法和案例。     

基于台风危害的厦门地区园林树木受损 原因研究

基于2016年9月16日1614号台风对厦门绿地的严 重影响，通过为期2个月对台风现场实地调研以及相关部门抢 险的数据统计，第一时间了解此次台风中厦门重要园林树种的 受害状况，分析树木在台风中的受损原因。台风灾害发生后给 厦门市的园林树木以及景观带来巨大的损害，因此对于厦门地 区园林树木受损原因的研究非常有必要。研究了受损原因后， 才可以在灾前以及灾后对重要的园林树木种进行栽培养护管 理，增加厦门绿化的抗灾能力以及灾后的及时恢复工作。     

调整燃烧降低飞灰含碳量

飞灰含碳量对火电厂经济运行有重要影响。本文主要研究通过对电厂锅炉燃烧方式的运行调整提高锅炉的效率和经济性的措施和方法。     

别墅区景观绿化种植施工技术研究

本文论述了葛洲坝世纪花园别墅区景观绿化施工中,针对施工土壤特性和反季节种植的特点,采取措施提高施工水平,控制施工工艺,以减小恶劣环境对苗木的影响,提高苗木成活率,保证景观质量。     

唐钢南厂区铁路运输与仓储设施的改造

对唐钢南厂区运输与仓储设施存在的问题进行了分析和总结。针对存在的不足,按照厂内运输系统优化的原则,从铁路站场改造、扩大仓储能力以及铁路运输设备重载化、专用化等方面提出运输方案及改造措施并实施,从而增强了唐钢南厂区的运输能力,提高了产品发运的物流服务水平。     

An options pricing approach to ramping rate restrictions at hydro power plants

This paper investigates the impact of ramping rate restrictions imposed on hydro operations to protect aquatic ecosystems. The optimal ramping decision is specified as an optimal control problem which results in a Hamilton Jacobi Bellman (HJB) equation. Electricity prices are modelled as a regime switching stochastic process. The optimal control is determined by solving the HJB equation numerically using a fully implicit finite difference approach with semi-Lagrangian time stepping. The paper focuses on the effect of ramping restrictions on a hydro plant׳s value and optimal operations, and provides an analysis of which factors cause ramping restrictions to have a greater or lesser impact on profitability. It is shown that hydro plant value is negatively affected by ramping restrictions, but the extent of the impact depends on key parameters which determine the desirability of frequent changes in water release rates. Interestingly for the case considered, value is not sensitive to ramping restrictions over a large range of restrictions. The results point to the importance of accurately modelling electricity prices in gauging the trade offs involved in imposing restrictions on hydro operators which may hinder their ability to respond to volatile electricity prices and meet peak demands.     

高压变频器在电厂凝结水泵上的应用

文章论述了高压变频器在燃煤发电厂大容量电动机上应用的必要性,介绍了凝结水泵的变频改造方案,分析了高压变频器改造的经济性,为同类型发电厂的节能降耗提供了借鉴经验和参考。