Stay and defend or leave early: Policy problems and experiences during the 2003 Victorian bushfires

Australian state and territory fire authorities advise residents to make a decision to prepare, stay and defend their properties from bushfires or leave well before the fire arrives in their area. The ‘Stay and defend or leave early’ policy is underpinned by strong evidence that well-prepared houses can be successfully defended and that late evacuation is a dangerous strategy. This paper presents the results of a study of the policy's implementation during the 2003 bushfires in North East Victoria and East Gippsland. Results suggest that despite high levels of awareness and support for the policy, there is some confusion over what it means to ‘stay and defend’ and ‘leave early’.     

Modified Weibull multi-state models for the analysis of animal carcinogenicity data

The Peto test is the standard method of analysis used in carcinogenicity studies to compare tumor incidence in groups of animals. It assumes that tumors are either instantly fatal or have no effect on mortality and requires a judgement of the lethality of each tumor. To avoid this requirement, parametric multi-state models have been proposed. In addition these allow estimation of tumor onset and mortality rates. This paper considers two such models and presents a modification. It is shown that the modified models provide a better fit to carcinogenicity data and simulated data are used to show that the modified models provide a modest increase in test power relative to the Peto test.     

PREDICTIVE CAPABILITIES OF BATCH-EXTRACT EXPERIMENTS USING WATER FROM A COAL MINE1

ABSTRACT: The ability of batch-extraction experiments to predict postmining ground water quality was evaluated. As a basis for evaluation, mineralogical and water quality data were used to identify the geochemical reactions that controlled the major-ion chemistry in batch-extraction experiments. The experiments used water and spoil material collected from a surface-coal mine in the Powder River basin of northeast Wyoming. The batch-extraction experiments consisted of a 2:1 solid:liquid ratio of ground water and spoil material (by weight). The chemical composition of the resulting batch-extracts was determined after a contact time of 24 hours. Thermodynamically-favorable reactions included calcite precipitation, gypsum dissolution, and formation of kaolinite as a result of orthoclase feldspar hydrolysis. Three reaction models were consistent with the therinodynanuc and mineralogic data. In general, the extracts had smaller major-ion concentrations than did the water samples collected from the spoil aquifer. Correction ratios were calculated from these experiments and could be used in combination with additional batch-extractions at existing or future lease areas to predict the quality of the ground water after mining.     

Transaction costs,communication and spatial coordination in Payment for Ecosystem Services Schemes

Agricultural producer participation and spatial coordination of land use decisions are key components for enhancing the effective delivery of ecosystem services from private land. However, inducing participation in Payment for Ecosystem Services schemes for coordinating land management choices is challenging from a policy design perspective owing to transaction costs associated with participation. This paper employs a laboratory experiment to investigate the impact of such costs on participation and land use in the context of an Agglomeration Bonus (AB) scheme. The AB creates a coordination game with multiple Nash equilibria related to alternative spatially-coordinated land use patterns. The experiment varies transaction costs between two levels (high and low), which affects the risks and payoffs of coordinating on the different equilibria. Additionally, an option to communicate is implemented between neighbors arranged on a local network to facilitate spatial coordination. Results indicate a significant difference in participation and performance under high and low transaction costs, with lower uptake and performance when transaction costs are high. These effects are, however, impacted by transaction costs faced in the past. Communication improves both AB participation rates and performance with the effect being greater for participants facing high transaction costs.     

Modeling and safety strategy of passenger evacuation in a metro station in China

The construction of metro in China is in a period of an unprecedented development in recent years, and the passengers are in high density within the metro during the operation time, the problem of occupant safety in emergencies has attracted more and more attentions. During the design and operation stages, modeling of the metro station evacuation capacity by using the computational models is an effective measure for guaranteeing the metro evacuation safety in the future. In this article, the safety strategy of evacuation in metro stations is first investigated and established, which involves the occupants needed to be evacuated, the evacuation route, and the safety zone. Then, an engineering calculation method for the metro station evacuation time is proposed. Based on the experimental data, simulation of evacuation process in different fire cases is conducted by using an agent-based model, so as to study the features of occupant evacuation behavior, the evacuation time, the passage flow rate, and the strategy of using the escalator as evacuation passage. These conclusions will be helpful for guiding the safe evacuation design of metros in China.     

Deflector Designs for Fish Habitat Restoration

Paired current deflectors are structures that are installed on each bank of a river to locally reduce the width of the channel, thereby creating flow acceleration and promoting scouring. These instream habitat structures have been used extensively in restoration projects to create pool habitat for fish, but there are many discrepancies in deflector design recommendations in terms of orientation, height, and length. Our objectives were to (1) examine how the angle, height, and length of paired deflectors affect scour hole dimensions and potential for bank erosion; and (2) test the applicability to paired deflectors of existing equations for scour hole depth and volume. Three deflector angles (45°, 90°, and 135°), two deflector heights (with flow under and over the deflector height), and two lengths (reducing the width by 25% and 50%) were investigated using uniform sand in a laboratory flume. Results showed a 26–30% smaller scour depth resulting from 45° deflectors than from 90° deflectors and a 5–10% smaller scour depth for 135° deflectors compared to 90° deflectors. The volume of scour and the potential for bank erosion were greater when flow was under the height of the deflectors rather than overtopping and when the length of deflector was increased. When flow was under the deflector height, 135° deflectors had the highest amount of bank erosion; whereas during overtopping flow conditions, 90° deflectors had the greatest bank erosion potential. Values predicted by the model of Kuhnle and others were closest to observed scour depth and volume measurements. The assumption that upstream-oriented deflectors always generate the largest scour should be revised.     

Tourists‘ and Locals‘ Preferences Toward Ecotourism Development in the Maya Biosphere Reserve,Guatemala

Ecotourism has been identified as a low impact means to provide income generating opportunities that are complementary to nature conservation as well as the welfare of the local population. The Maya Biosphere Reserve in Peten, Guatemala is one of Central America's largest and most isolated protected areas. And although the area is contains a well-visited archeological site, it has not been developed for ecotourism. In this study choice experiments are used to analyze the preferences toward alternative scenarios of ecotourism of two important stakeholder groups: foreign tourists and educated local residents. Results demonstrate that these two populations of have unequal but similar preference orderings, especially toward: improved national park management and the presence of guides for wildlife viewing. These stakeholder groups had different opinions toward paved access roads and the presence of illegal colonists within the protected area. Both populations favored an entrance fee toward the absence of an entrance fee. These preferences were generally consistent across other socioeconomic indicators. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

Estimating the benefits and costs to mountain bikers of changes in trail characteristics,access fees,and site closures: choice experiments and benefits transfer

Mountain biking is an increasingly popular leisure pursuit. Consequences are trail degradation and conflicts with hikers and other users. Resource managers often attempt to resolve these problems by closing trails to mountain biking. In order to estimate the impact of these developments, a model has been devised that predicts the effects of changes in trail characteristics and introduction of access fees, and correlates these with biker preference on trail selection. It estimates each individual's per-ride consumer's surplus associated with implementing different policies. The surplus varies significantly as a function of each individual's gender, budget, and interest in mountain biking. Estimation uses stated preference data, specifically choice experiments. Hypothetical mountain bike trails were created and each surveyed biker was asked to make five pair-wise choices. A benefit-transfer simulation is used to show how the model and parameter estimates can be transferred to estimate the benefits and costs to mountain bikers in a specific area.     

高校宿舍楼火灾及人员疏散数值研究

为研究高校宿舍火灾烟气蔓延过程与人员疏散效果的相关联系,利用数值模拟研究了不同火灾场景下烟气流动、能见度、温度随时间变化的规律,及其对人员安全疏散的影响。研究表明:(1)火灾发生后,由于烟囱效应,烟气迅速在楼梯间蓄积,形成蓄烟池效应,堵塞疏散通道,然后逐渐发展至上部的楼层空间,对人员安全疏散极为不利;(2)高校宿舍楼人员较为集中,火灾发生时疏散人员在楼梯间易出现拥堵,人员火灾安全疏散的形势较为严峻;(3)喷淋、宿舍人数控制、建筑结构优化等安全措施能有效提高人员疏散效果,降低火灾危险性;(4)研究成果能为建筑防火设计、消防整改和宿舍管理提供科学依据。     

Explosion at an aluminum factory caused by the July 2018 Japan floods: Investigation of damages and evacuation activities

An explosion at an aluminum factory occurred due to floods in Soja City, Okayama Prefecture, in July 2018. This study investigates the accident, its overall impact on local residents, and emergency management activities. The results of the study showed that several nearby structures and homes were damaged by the explosion. Concern for more explosions has led to the evacuation of residents of Shimobara area of Soja City. In Shimobara, residents had carried out voluntary disaster prevention activities before the disaster. After the explosion, Shimobara residents were able to evacuate safely in cooperation with the voluntary disaster prevention organization and the local government agency. The study revealed that there was a lack of information on chemical accident hazards shared by the factory with local government authorities and first responders, as well as with local residents. In order to be better prepared for technological accidents, and in particular accidents caused by natural disasters (known as Natechs), mechanisms for information sharing between companies and municipalities should be adopted.