Value added and secondary benefits in regional projection evaluation: Irrigation development in the Snake River basin

Benefit/cost methodologies are well accepted for project analysis from a national perspective. Recent pressure to develop local decisionmaking and local funding for water projects has focused attention on the regional costs and benefits of such development. This paper examines some methodological issues that emerge as one attempts to estimate these regional costs and benefits. Uncritical use of regional economics procedures and concepts such as input-output analysis and value added to measure the primary and secondary impacts of these projects carries the risk of seriously overestimating regional project benefits. The paper concludes that new approaches to regional project analysis must be developed that will reconcile and incorporate regional economics procedures with benefit/cost methodology.     

Potential dermal exposure to deltamethrin and risk assessment for manual sprayers: influence of crop type

A comparison of the Potential Dermal Exposure (PDE) of workers to the insecticide deltamethrin was made as a function of crop type, in small agricultural production units in Argentina. Seven experiments were done with two different crops (maize and broccoli, treated area between 600 and 1000 m(2)) with three different operators under typical field conditions using a lever operated knapsack. The methodology is based on the whole body dosimetry technique, presenting separately the data for mixing/loading and application activities. These results indicate a higher concentration of pesticide in lower body sections for broccoli and a wider distribution for maize. The risk inherent in these agricultural procedures is estimated through Margin of Safety (MOS) values and was found to be generally safe. Preliminary results of a mass balance distribution of the pesticide between crop, soil and operator are also presented.     

Second generation anticoagulant rodenticides in tawny owls (Strix aluco) from Great Britain

Secondary exposure of vertebrate predators to second generation anticoagulant rodenticides (SGARs) is widespread in Britain. Tawny owl (Strix aluco) populations in the UK are thought to have declined since the 1970s, when SGARs were first introduced, and these compounds may have contributed to any decline in owl numbers. Our aims were to conduct the first systematic survey of SGAR exposure in tawny owls and ascertain whether there had been a change in the proportion of exposed birds that was concurrent with the decline in the population. Liver difenacoum, bromadiolone, flocoumafen and brodifacoum concentrations in British tawny owls from two periods (1990-1993 and 2003-2005) were quantified. In total, some 20% of birds contained detectable residues of one or more SGAR. The extent of exposure (% of birds exposed, magnitude of residues) to different SGARs did not change consistently between time periods. Of the raptors analysed to date in Britain, tawny owls had the lowest proportion of individuals that contained detectable liver residues and so appear to be the least vulnerable to exposure and/or assimilation of SGARs. We found no clear evidence to implicate SGARs as a major factor affecting tawny owl numbers in Britain between 1990 and 2005.     

静静地改革

虽然在国外市场鲜有人知,但是作为俄罗斯最大的汽车制造商之一、RusPromAuto控股公司的成员Gaz集团,目前已经是该国本土最大的工程机械制造商。Richard High报道。     

The Thames

Richard MacCormac evokes the Thames' defining relationship with London, as the boundary between north and south, the primacy of the north bank having remained almost unchallenged until the 21st century with the development of Tate Modern and the rejuvenation of the south bank. Copyright © 2012 John Wiley & Sons, Ltd.     

State of the practice review of heap leach pad design issues

The authors present a summary of the state of the practice of containment design in copper and gold heap leaching, focusing on recent advancements and how these applications differ from the more conventional landfill design practices. Advancements both within the Americas and worldwide are presented, including consideration of increasing heap depths, which are now approaching 150 m (with ore densities generally in the range of 1500–1800 kg/m³). Liner system performance under these pressures will be reviewed, including the latest developments in drainage pipe performance testing. The authors will also explore the recently emerging technology of using concentrated sulfuric acid pre-curing for copper ores and the related compatibility issues with conventional geomembrane materials.     

Sublethal Effects of Fire Smoke

Fire smoke toxicity has been a recurring theme for fire safety professionals for over four decades. There especially continue to be difficulty and controversy in assessing and addressing the contribution of the sublethal effects of smoke in hazard and risk analyses. The Fire Protection Research Foundation (FPRF), the National Institute of Standards and Technology (NIST), and NFPA have begun a private/public fire research initiative, the International Study of the Sublethal Effects of Fire Smoke on Survival and Health (SEFS) to provide scientific information on these effects for public policy makers. The papers in this issue of Fire Technology present results from the first phase of the project: estimates of the magnitude and impact of sublethal exposures to fire smoke on the U.S. population, the best available lethal and incapacitating toxic potency values for the smoke from commercial products, the potential for various sizes of fires to produce smoke yields that could result in sublethal health effects, and state-of-the-art information on the production of the condensed components of smoke from fires and their evolutionary changes during transport from the fire.     

条形荷载下加筋土边坡破坏机制的数值模拟

为了克服模型的尺寸效用,获得加筋与不加筋边坡在条形荷载下的各种性状参数和边坡的破坏机制,建立用于分析和模拟3个大型室内足尺加筋与不加筋边坡破坏机制的数值计算模型。边坡回填材料采用级配较差的粗砂,土体的非线性弹性响应采用Duncan-Chang双曲线模型E-B模式加以描述,破坏准则采用Mohr-Coulomb屈服准则,并采用与屈服条件不相关联的流动法则。加筋材料采用两节点的弹塑性锚索结构单元进行模拟,并采用无厚度的弹簧-滑动系统来模拟筋土之间的相互作用和相对运动。数值计算采用基于有限差分的连续介质快速拉格朗日分析方法(FLAC),分别对与破坏面位置和形态密切相关的节点位移速度向量、塑性区和剪应变速率分布3个参数进行了计算,获得了3个边坡在条形极限荷载下的双楔体破坏机制和极限承载力,与试验结果吻合较好,验证了模型的可行性。在此基础上,对不同的条形荷载位置及不同填土材料强度下边坡破坏机制进行了数值模拟和分析。研究结果表明,无论加筋与不加筋边坡,当条形荷载位置距坡肩的距离减小时,边坡破坏面形态由双楔体过渡到圆弧形;当填土材料强度降低时,破裂面形态转化为圆弧形或对数螺线形。     

Projection of hazardous air pollutant emissions to future years

Projecting a hazardous air pollutant (HAP) emission inventory to future years can provide valuable information for air quality management activities such as prediction of program successes and helping to assess future priorities. We have projected the 1999 National Emission Inventory for HAPs to numerous future years up to 2020 using the following tools and data: the Emissions Modeling System for Hazardous Air Pollutants (EMS-HAP), the National Mobile Inventory Model (NMIM), emission reduction information resulting from national standards and economic growth data. This paper discusses these projection tools, the underlying data, limitations and the results. The results presented include total HAP emissions (sum of pollutants) and toxicity-weighted HAP emissions for cancer and respiratory noncancer effects. Weighting emissions by toxicity does not consider fate, transport, or location and behavior of receptor populations and can only be used to estimate relative risks of direct emissions. We show these projections, along with historical emission trends. The data show that stationary source programs under Section 112 of the Clean Air Act Amendments of 1990 and mobile source programs which reduce hydrocarbon and particulate matter emissions, as well as toxic emission performance standards for reformulated gasoline, have contributed to and are expected to continue to contribute to large declines in air toxics emissions, in spite of economic and population growth. We have also analyzed the particular HAPs that dominate the source sectors to better understand the historical and future year trends and the differences across sectors.     

Addressing the Needs of People Using Elevators for Emergency Evacuation

US model codes and building regulations are recognizing the provision of protected elevators for occupant self-evacuation after more than two decades of training people that elevators are unsafe in fires. This reversal will require that people can readily identify those elevators that are safe to use and be provided with information and reassurances during use that the system is functioning safely. Lengthy discussions on the interactions between the systems and users have resulted in requirements for visual, audible, and voice messaging systems and operational protocols designed to provide reliable, real-time information needed by users to make informed decisions. The discussions have further identified the need for public education to provide for effective use by infrequent visitors to buildings equipped with these systems. The paper will discuss the approaches being developed to address these needs by a consortium of public and private organizations including the American Society of Mechanical Engineers (ASME), National Institute of Standards and Technology (NIST), National Elevator Industry Inc. (NEII), disability advocacy groups, and the fire alarm and model building code developers. There is an expectation that since a building’s elevators are used daily by the occupants, by keeping the system used in emergencies as close as possible to normal use, the provision of additional information on status and safety will represent sufficient reassurance to users. One of the outstanding issues identified in the discussions is the need for testing and verification that the approaches will be effective. Due to the difficulties inherent in human testing, there is a need for the inclusion of these features into observational research being conducted through required evacuation drills. Since elevator use is not prohibited now for non-fire emergency egress, this may provide the opportunity to test public response to the approaches being contemplated. The paper will suggest ideas for such research being included in planned studies and as a part of building commissioning.