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981.
We explored the possible future impacts of increased coastal flooding due to sea level rise and the potential adaptation responses of two urban, environmental justice communities in the metropolitan Boston area of Massachusetts. East Boston is predominantly a residential area with some industrial and commercial activities, particularly along the coastal fringe. Everett, a city to the north of Boston, has a diversified industrial and commercial base. While these two communities have similar socioeconomic characteristics, they differ substantially in the extent to which residents would be impacted by increased coastal flooding. In East Boston, a large portion of residents would be flooded, while in Everett, it is the commercial/industrial districts that are primarily vulnerable. Through a series of workshops with residents in each community, we found that the target populations do not have an adaptation perspective or knowledge of any resources that could assist them in this challenge. Furthermore, they do not feel included in the planning processes within their communities. However, a common incentive for both communities was an intense commitment to their communities and an eagerness to learn more and become actively engaged in decisions regarding climate change adaptation. The lessons that can be applied to other studies include 1) images are powerful tools in communicating concepts, 2) understanding existing cultural knowledge and values in adaptation planning is essential to the planning process and 3) engaging local residents at the beginning of the process can create important educational opportunities and develop trust and consensus that is necessary for moving from concept to implementation.  相似文献   
982.
Laser forming process is used in forming and bending of metallic and non-metallic sheets. Laser beam irradiation causes a localized temperature increase and a localized mechanical strength decrease. In this article, an external mechanical force is added to a laser beam irradiation, which is called external force-assisted laser forming process, to gain a 90-degree bending angle. Furthermore, Numerical simulation of the process is performed to achieve a good understanding of the process. Simulation results show that more than two-third of the final forming is due to the laser beam irradiation. Equivalent plastic strain values during laser forming and external force-assisted laser forming processes are compared. Results show that equivalent plastic strain in laser forming process increases in a step pattern, with increasing in scan pass numbers. This occurs because when the laser beam irradiates on the sheet surface, it reduces the yield strength of the sheet. Equivalent plastic strain in external force-assisted laser forming process has an oscillatory step nature. This attributes to simultaneous effects of strain hardening and thermal induced reduction of yield strength of the sheet. Simulations were in good accordance with experiments.  相似文献   
983.
Several researchers have stressed the need for a proper implant-patient match in hip joint replacements, in particular, for cementless femoral stems. Some of the complications of mismatch are aseptic loosening, improper load distribution, and discomfort. In this study, the differences in dimensions between femurs of elderly Indians and those of populations from other regions are compared in order to solve the problem of a possible geometric mismatch between a selected implant and the femurs of an Indian patients are concerned. This paper also describes a methodology for implant designing from measured anthropometric data, fit evaluation, finite element (FE) stress analysis and subsequently implant manufacturing using the CAM (Computer Aided Manufacturing) technique. The machining of the Titanium alloy femoral stem is usually performed on a 5 Axis CNC (Computer Numerical Control) machining center. However, in this study the machining of the femoral stem was effectively performed on a 3 Axis CNC machining center to emphasize on economical benefits for low cost manufacturing strategy.  相似文献   
984.
A new modeling effort exploring the opportunities, constraints, and interactions between mitigation and adaptation at regional scale is utilizing stakeholder engagement in an innovative approach to guide model development and demonstration, including uncertainty characterization, to effectively inform regional decision making. This project, the integrated Regional Earth System Model (iRESM), employs structured stakeholder interactions and literature reviews to identify the most relevant adaptation and mitigation alternatives and decision criteria for each regional application of the framework. The information is used to identify important model capabilities and to provide a focus for numerical experiments. This paper presents the stakeholder research results from the first iRESM pilot region. The pilot region includes the Great Lakes Basin in the Midwest portion of the United States as well as other contiguous states. This geographic area (14 states in total) permits cohesive modeling of hydrologic systems while also providing strong gradients in climate, demography, land cover/land use, and energy supply and demand. The results from the stakeholder research indicate that, for this region, iRESM should prioritize addressing adaptation alternatives in the water resources, urban infrastructure, and agriculture sectors, including water conservation, expanded water quality monitoring, altered reservoir releases, lowered water intakes, urban infrastructure upgrades, increased electric power reserves in urban areas, and land use management/crop selection changes. For mitigation in this region, the stakeholder research implies that iRESM should focus on policies affecting the penetration of renewable energy technologies, and the costs and effectiveness of energy efficiency, bioenergy production, wind energy, and carbon capture and sequestration.  相似文献   
985.
PROBLEM: Hospital nurses have one of the highest work-related injury rates in the United States. Yet, approaches to improving employee safety have generally focused on attempts to modify individual behavior through enforced compliance with safety rules and mandatory participation in safety training. We examined a theoretical model that investigated the impact on nurse injuries (back injuries and needlesticks) of critical structural variables (staffing adequacy, work engagement, and work conditions) and further tested whether safety climate moderated these effects. METHOD: A longitudinal, non-experimental, organizational study, conducted in 281 medical-surgical units in 143 general acute care hospitals in the United States. RESULTS: Work engagement and work conditions were positively related to safety climate, but not directly to nurse back injuries or needlesticks. Safety climate moderated the relationship between work engagement and needlesticks, while safety climate moderated the effect of work conditions on both needlesticks and back injuries, although in unexpected ways. DISCUSSION AND IMPACT ON INDUSTRY: Our findings suggest that positive work engagement and work conditions contribute to enhanced safety climate and can reduce nurse injuries.  相似文献   
986.
INTRODUCTION: The study reported here was designed to test the ability of the theory of planned behavior to mediate the effect of parental supervision on adolescents' intentions to violate driving rules. METHOD: A representative sample of 1,654 adolescents completed questionnaires during individual and anonymous interviews carried out at their schools. RESULTS: Results showed that age, gender, prior risky driving-behavior, and parental supervision significantly predict intentions to violate driving rules. Attitude and the subjective norm partially mediate the effect of age, prior behavior, and parental supervision. Perceived behavioral control does not predict intention and is not predicted by other variables. IMPACT: The results suggest that social cognitive variables partially mediate the effect of parenting practices such as supervision.  相似文献   
987.
INTRODUCTION: Although the LATCH System (Lower Anchors and Tethers for Children) holds the promise of simplifying the installation of a child restraint system (CRS) to the vehicle's seat, many drivers transporting young children have difficulties using this technology. This paper reports on an observation study of LATCH use and misuse. METHOD: Observations of approximately 1,000 children less than 5 years of age in CRSs, in the back seats of vehicles that were equipped with tether and lower anchors, in seven states. RESULTS: Tethers were used for 51% of the children when the forward-facing CRS had tether straps and the vehicle had tether anchors. Lower anchors were used for 58% of the children when the CRS had lower attachments and the vehicle had lower anchors. The most common tether and lower attachment misuses were loose tether straps (18% of cases) and loose lower attachment installation (30% of the cases), respectively. Vehicle safety belts were used in combination with lower attachments in 20% of all lower anchor installations. CONCLUSION: As more caregivers of young children drive vehicles equipped with LATCH, it will be important to promote the proper installation of CRSs using this technology. LATCH education messages must also emphasize that the lower anchors may not always be the safest choice for CRS attachment -- the safest attachment is the one that results in a tight fit and will be used correctly consistently.  相似文献   
988.
989.
OBJECTIVES: Zero tolerance (ZT) laws have been effective in reducing alcohol-related crashes among underage drivers. However, enforcement in some states has not been rigorous, and ZT offenses may not be viewed as serious offenses. On July 1, 1994, the state of Washington implemented a ZT law that allowed police to request a test for alcohol on suspicion of either a ZT or driving-under-the-influence (DUI) offense. The present study examined effects of the ZT law on arrests and case dispositions among underage offenders as a function of blood alcohol concentration (BAC) and post-law patterns of recidivism. METHODS: Times-series analyses examined the effects of the ZT law on trends in arrests of underage drivers between 1991 and 1999. Based on arrest records matched with driver's license records, the effects of the law on dispositions of alcohol-related offenses among underage drivers were examined, and rates of recidivism among underage offenders were examined for the period following the ZT law. RESULTS: There was a substantial increase in arrests of underage drivers beginning immediately after implementation of the ZT law, especially among drivers with low BACs. The types of court or administrative dispositions received by underage offenders changed markedly after the ZT law was implemented. Underage offenders with lower BACs became far more likely to receive alcohol-related convictions and/or license suspensions. However, the percentage of underage offenders with higher BACs receiving DUI convictions declined as some of these offenders received the lesser ZT disposition. After the ZT law, underage offenders with BACs of 0.10 g/dL or higher were more likely to recidivate than those with lower BACs, but appreciable proportions of drivers were re-arrested for another alcohol offense, whatever the BAC and however they were penalized. CONCLUSIONS: Implementation of Washington's law indicates that a ZT law can increase the likelihood that an underage person will be sanctioned for drinking and driving. However, recidivism remains an issue as more than one in four underage drivers arrested with low BACs subsequently were re-arrested.  相似文献   
990.
OBJECTIVE: Since the shoulders are rarely seriously injured in frontal or oblique collisions, they have been given low priority in the development of frontal impact crash test dummies. The shoulder complex geometry and its kinematics are of vital importance for the overall dummy kinematics. The shoulder complex also influences the risk of the safety belt slipping off the shoulder in oblique forward collisions. The first aim of this study was to develop a new 50th percentile male THOR shoulder design, while the second was to compare the new shoulder, mounted on a THOR NT dummy, with volunteer, THOR NT, and Hybrid III range of motion and stiffness data. The third aim was to test the repeatability of the new shoulder during dynamic testing and to see how the design behaves with respect to belt slippage in a 45 degrees far-side collision. METHODS: The new 50th percentile THOR shoulder design was developed with the aid of a shell model of the seated University of Michigan Transportation Research Institute (UMTRI) 50th percentile male with coordinates for joints and bony landmarks (Schneider et al., 1983). The new shoulder design has human-like bony landmarks for the acromion and coracoid processes. The clavicle curvature and length are also made similar to that of a male human, as is the range of motion in the anterior-posterior, superior-inferior, and medial-lateral directions. The new shoulder design was manufactured and tested under the same conditions that T?rnvall et al. (2005b) used to compare the shoulder range of motion for the volunteers, Hybrid III, and THOR Alpha. The new design was also tested in two dynamic test configurations: the first was a 0 degrees full-frontal test and the second was a 45 degrees far-side test. The dummy tests were conducted with an R-16 seat with a three-point belt, the Delta V was 27.0+/-0.5 km/h and the maximum peak acceleration was approximately 14.6+/-0.5 g for each test. RESULTS: A new shoulder design with geometry close to that of humans was developed to be retrofitted to the THOR NT dummy. The results showed that the range of motion for the new shoulder complex during static loading was larger by at least a factor of three, for the maximum load (200 N/arm), than that of either the Hybrid III or the THOR NT; this means it was more similar to the volunteers' range of motion. It was observed that the THOR NT with the new shoulder did not slide out of the shoulder belt during a far-side collision. The performance of the new shoulder was reasonably repeatable and stable during both the static tests and the sled tests. CONCLUSION: A new shoulder for the THOR NT has been designed and developed, and data from static range of motion tests and sled tests indicate that the new shoulder complex has the potential to function in a more human-like manner on the THOR dummy.  相似文献   
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