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721.
C. M. Ryan P. S. McDonald D. S. Feinberg L. W. Hall J. G. Hamerly C. W. Wright 《Coastal management》2017,45(1):73-89
Shellfish aquaculture can result in conflicts among stakeholders who perceive impacts and tradeoffs regarding sense of place, aesthetic, recreational, economic, and ecological values. Pacific geoduck clams (Panopea generosa Gould 1850) are grown in intertidal plots using gear- and labor-intensive techniques that result in a high value export product. A confluence of issues has resulted in on-going social and legal tensions surrounding geoduck aquaculture in southern Puget Sound, Washington (WA), USA. Using interviews and document analysis, we explored stakeholder perspectives and policy issues related to geoduck aquaculture in southern Puget Sound. Twenty-three stakeholders were interviewed, including state agency employees, representatives of the aquaculture industry, nongovernmental organizations, landowners, a tribal member, and an academic. Nine state hearings board decisions on challenges to aquaculture permits were also analyzed. Stakeholders articulated a variety of perspectives regarding aesthetic, recreational, land-use, ecological, political, regulatory, and economic aspects of geoduck aquaculture activities. Hearings board cases addressed similar issues (aesthetic, ecological, and recreational), as well as challenges to restrictions on aquaculture. Potential strategies for managing this conflict include emphasizing best management practices, identifying and incorporating best available science, joint fact-finding approaches, and initiating and improving communication among all stakeholders. 相似文献
722.
Allison J. James Ulf G. Schriever Sanaz Jahangiri Sinem C. Girgin 《WMU Journal of Maritime Affairs》2018,17(2):293-310
The International Maritime Industry (IMI) is a global web of shipping, connecting all Continents and bringing together mariners from a multitude of national, ethnic and linguistic backgrounds. Wherever humans interact, they communicate in some form or another and the ability to communicate competently is the cornerstone of safety at sea. This paper identifies the growth of English as the lingua franca of the sea, as a framework for the later discussion on current teaching practices. We consider that Maritime English (ME) fits into the category of a special-purpose form of English, in that it has generated, modified or adopted from other languages many terms and phrases that are only used in the IMI. This paper considers safety-to-practice as a factor in curriculum design, teaching and assessment as the basis for ME competence. Further, we propose opportunities to move industry focus forward, through collaboration with stakeholders and discussion about teaching practices. This paper identifies a gap in maritime teaching practices. This paper further explores the use of authentic teaching as a way forward to improve maritime communication. 相似文献
723.
Using the nationally representative dataset of the 2007 Pakistan Time-Use Survey, this paper examines gender differences in daily trip rate, mode choice, travel duration, and purpose of travel, which are previously unreported because of limited data availability. Wide gender mobility gaps are observed in the country, where women are less likely to travel, are half as mobile as men and may rely heavily on walking. The particular social and cultural context of the country, that renders women as private, secluded and family honor, seems influential in shaping their mobility and choice of activities. Demographic factors such as age, household income, and marital status significantly decrease female mobility levels. Hence, these findings call for a gender-based culturally responsive transportation policy in the country. 相似文献
724.
Matthew G. Karlaftis Dimitrios Tsamboulas 《Transportation Research Part A: Policy and Practice》2012,46(2):392-402
The need to measure transit system performance along with its various dimensions such as efficiency and effectiveness has led to the development of a wide array of approaches and vast literature. However, depending upon the specific approach used to examine performance, different conclusions are oftentimes reached. Using data from 15 European transit systems for a ten year time period (1990-2000), this paper discusses three important transit performance questions; (i) Do different efficiency assessment methodologies produce similar results? (ii) How are the two basic dimensions of transit performance, namely efficiency and effectiveness, related? and (iii) Are findings regarding organizational regimes (public operations, contracting and so on) sensitive to the methodological specifications employed? Results clearly indicate that efficiency scores and associated recommendations are sensitive to the models used, while efficiency and effectiveness are - albeit weakly - negatively related; these two findings can have far reaching policy implications. 相似文献
725.
P.P. Koh Y.D. WongA.P.G. Menon 《Transportation Research Part D: Transport and Environment》2012,17(2):179-183
This paper considers the impact on local residents of audible pedestrian signals (APS) that provide cues to the visually handicapped pedestrians on the onset of the various signal phases at a signalized crosswalk. We investigate the extent of the noise intrusion problem of APS through understanding the acceptability by the general public. From the perception surveys conducted, vehicle engine/braking sound, neighbor talking/playing and vehicle alarm are the top three irritating noises experienced while sleeping whereas audible signals is ranked at 21st position. The maximum sound level of the signals found to be acceptable indoors is close to 60 dBA. 相似文献
726.
Air transportation in Brazil has been recently liberalized and one of the consequences of this process is the concentration of flights in a few hubs. During the years 2006-2007 two fatal accidents created unprecedented chaos in both land and air sides of the system with harmful consequences to tourism in Brazil. The consequences were more airport congestion and many episodes of flight delays and cancellations that lasted for several months. We argue that, among other factors, this state of blackout was a result of the increase in the degree of concentration in few airports, particularly Congonhas (in São Paulo) and Brasília. Using data obtained from a survey with Brazilian experts, a comparison was made with two existing methods (the one used by the US Federal Aviation Administration and the usual Herfindahl-Hirschman method) in order to calculate the number of hubs in Brazil. Due to the huge discrepancy obtained between data from the survey and the other two methods considered, a new mathematical method based on the Herfindahl-Hirschman Index was proposed to identify the number of hubs in a given network. Drawing from the examples of what happened to tourist destinations during and after the air transport crisis in Brazil, the article concludes discussing the need for a more accurate tool to identify and to monitor the concentration of flights at the Brazilian air transportation network and its importance to tourism. 相似文献
727.
There are many ways of describing a solid,porous or fluid region of the computational domain when solving the Navier-Stokes equations(NSE)for flow motions.Amongst these the porous cell method is one of the most flexible approaches.In this method,a parameter is defined as a ratio of the volume open to water and air in a calculation cell to its cell volume.In the calculation,the same numerical procedure is applied to every cell and no explicit boundary conditions are needed at solid boundaries.The method is used to simulate flow through porous media,around solid bodies and over a moving seabed.The results compare well with experimental data and other numerical results.In our future work the porous cell method will be applied to more complex fluid-solid interaction situations. 相似文献
728.
H. Liu G.N Liu K J Huo T Liu X H Zhang K Liu K Tao Y. J. Liu . Mechanical Engineering School Xi''''an Jiaotong University Xi''''an China . Strength Centre Zhengzhou Research Institute of Mechanical Engineering Zhengzhou China . Fo 《上海交通大学学报(英文版)》2000,(1)
IntroductionThefiwtee1emenmethod(FEM)playsanextrmelyimPortantroleintheanalysesofengineeringproblems.ForalongtimethismethodhasmainlybeenaPPliedinthelinearfieldandshownitsgreatpower.HoweveealOtofnonlinearengineeringPrOblemsWhichcanneitherbesimPlyreducedtolinearonesnorrCPresentedbylinearlyanalogywhichshallchnsethePfacticalconditionsrelativelymuch,havechallengedfiniteelementmethod(FEM).RecentymuchProgresshasbeenmadebothinthemathematicalandmechanicaltheoryandthecomPulertechnologysothatevent… 相似文献
729.
Dan B. Marghitu David G. Beale S.C. Sinha 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1997,28(1):41-55
Computer simulations of a driven vehicle are performed to assess and quantify the automobile stability. The analytical methodology is based on PoincarS maps and Floquet theory, which are commonly used to investigate the stability of periodic systems. The approach accommodates the study of the complex dynamics of vehicle locomotion under various configurations of the system. The proposed method does not require any knowledge regarding the inner structure of the vehicle model. Kinematic data is simply collected at the specific instants to conduct the analysis. It is found that this method has the potential for real time warning and control of vehicle instabilities. 相似文献
730.
G. Ruf 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1978,7(1):1-23
When applying the known power spectra of the random road roughness to the suspension behaviour of a four-wheeled vehicle, each of the four vertical input signals together with their related interdependence are to be considered, if exact results are to be obtained. The correlations are determined by way of calculation. The resulting roughness spectra of bounce, pitch, roll and torsional excitations will be applied to various vehicles, characterized by different design parameters. By means of a three-dimensional simulation model the virtual values of the random vehicle vibrations are calculated, while determining at the same time the influence of vehicle speed, waviness exponent, track width, wheel base, and axle design feature as well as the relationship between the vertical vibrations and the reference point in the vehicle body. 相似文献