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981.
Jani Häkkinen Vuokko Malk Antti Posti Olli-Pekka Penttinen Riikka Mäkelä Anna Kiiski 《WMU Journal of Maritime Affairs》2013,12(2):147-160
The environmental hazard potential of a total of 15 chemicals that are transported through the Finnish coastal areas was assessed in this paper using a scoring method developed for accidents. The study indicates that the chemicals most commonly transported/handled in Finnish ports are methanol, sodium hydroxide solution, acids, pentanes, phenol, xylenes, methyl tert-butyl ether, ethanol and ethanol solutions. For the evaluation of the environmental hazardousness of various chemicals, a priority list of chemicals that are the most commonly transported regionally in marine environments was compiled for this study. The method used has many similarities to other commonly used scoring systems, but this study gave more weight to specific characteristics of an accidental release, water biota and impact on the environment. Nonylphenol, ammonia and sulphuric acid ranked as the most hazardous substances on the list. The results of the study can be used by rescue and environmental authorities and enterprises to improve preparedness for accidents and to mitigate the effects of accidental spills. 相似文献
982.
983.
M. Khaled M. Gad El Rab F. Hachem H. Elhage A. Elmarakbi F. Harambat H. Peerhossaini 《International Journal of Automotive Technology》2016,17(4):617-627
Fans are often tested without downstream blockage and, thus, the performance is considerably different when the fan is mounted in a vehicle as part of a cooling system and where high blockage effect is present downstream. The aim of the present work is to analyze by laser Doppler velocimetry LDV measurements the topology of the flow induced by a fan incorporated in a simplified underhood model reproducing engine blockage and to study the blockage effect of the engine positioning on the flow induced by the fan. The distance between the fan and the engine block affects the mean flow axial velocity U. The vertical velocity component W is greatly influenced by the variation of the distance between the fan and the engine block, both in magnitude and topology. 相似文献
984.
L. Lukacs M. Dassanayake R. Magalhaes C. Fontes M. Embirucu I. M. Pepe 《International Journal of Automotive Technology》2011,12(4):579-588
The vehicular illumination system has undergone considerable technological advances in recent decades such as the use of a Light Emitting Diode (LED) Adaptive Front-lighting System (AFS), which represents an industry breakthrough in lighting technology and is rapidly becoming one of the most important innovative technologies around the world in the lighting community. This paper presents AFS control alternatives using fuzzy logic (types 1 and 2) to determine its operating parameters taking into consideration the road conditions in the state of São Paulo (Brazil). Fuzzy logic is a well-known extension of the conventional (Boolean) logic that enables the treatment of uncertainty present in the information through the definition of intermediary membership values between the “completely true” and the “completely false”. This technique or modeling strategy is particularly important when a multi-parameter decision must be taken or the decisions are based on the human knowledge. The results show the potential of the methodology proposed and its suitability for light control providing safer nighttime driving. 相似文献
985.
The Ensemble Kalman filter (EnKF) has been applied to a 1-D complex ecosystem model coupled with a hydrodynamic model of the Ligurian Sea. In order to improve the performance of the EnKF, an ensemble subsampling strategy has been used to better represent the covariance matrices and a pre-analysis step for correcting the non-normality of the members distribution has been implemented. Twin experiments have been realized to assess the performance of the developed tool and a real data assimilation experiment has been conducted to hindcast the ecosystem at the Dyfamed site during the year 2000. Finally the performance of the EnKF has been compared with a Singular Evolutive Extended Kalman (SEEK) filter with a fixed basis. We conclude that, on one hand, there is a benefit in using the subsampling strategy and the lognormal transformation with the EnKF, and on the other hand, this filter presents better performance than the fixed basis version of the SEEK filter. However, it also incurs a large computational cost. 相似文献
986.
Data assimilation is used in numerical simulations of laboratory experiments in a stratified, rotating fluid. The experiments are performed on the large Coriolis turntable (Grenoble, France), which achieves a high degree of similarity with the ocean, and the simulations are performed with a two-layer shallow water model, using the SEEK method for data assimilation. Since the flow is measured with a high level of precision and resolution, a detailed analysis of a forecasting system is feasible. The procedure is tested for the baroclinic instability of a two-layer vortex. It is shown that the method of data assimilation properly captures the details of the initial flow perturbation. Then it is shown by sensitivity studies that an error of the model, attributed to small non-hydrostatic effects, can be distinguished from the error growth associated with the intrinsic instability of the system. Finally, it is experimentally demonstrated that the velocity field in the lower layer can be well controlled by data assimilation limited to the top layer. 相似文献
987.
B. Unver Y. Koyuncuoglu M. Gokasan S. Bogosyan 《International Journal of Automotive Technology》2016,17(1):13-34
The ultimate aim of this study is the development of an engine modeling approach that would facilitate the design of model-based control techniques for diesel engines. This will allow for the development of more generalized, modular control strategies for different engine types and sizes as opposed to the commonly practiced map-based engine control strategies that depend on maps and feedforward control and require lengthy modifications every time a change is made. Also, most engine modeling studies focus on either airpath or combustion systems, treating these models and their validation individually, and not as an integrated system as is actually the case. To address the need for more realistic models suitable for model-based control design, this study develops a combined airpath and combustion model for the engine, using analytical models wherever possible and derives a model with appropriate control inputs and outputs that could be used in a control scheme. The inclusion of the actuator dynamics of the Exhaust gas recirculation (EGR), variable geometry turbine (VGT), and Throttle (THR) valves in the airpath model and the consideration of nonlinearities in the combustion model allow for the development of a more thorough engine model, as well as the validation of subsystems and the whole integrated engine model using a complete World Harmonized Transient Cycle (WHTC). This test cycle finds limited use due to its challenging transients, and yet, is the demanded test cycle for emission regulations nowadays. These are unique aspects of this modeling study, the results of which indicate that the developed engine model could be used in control design and hardware-in-the-loop simulation (HILS) based engine control prototyping. 相似文献
988.
Internalisation of the external costs of transport is currently the subject of much debate. Estimation of costs such as those
of pollution and congestion is a primary element in any strategy involving policies for use in the internalisation of these
costs. The objective of the TRENEN II STRAN project, funded by the EU, was to develop a methodology for estimation of the
marginal external costs of transport. The model developed during the project was used in a series of case studies. One of
the case studies, that conducted for Dublin, is reported in this paper. A brief summary of the TRENEN approach is presented
followed by the results for Dublin produced from policies such as Do Nothing, Uniform pricing (internalising external costs
by means of fuel taxation), Congestion Pricing (cordon pricing) and a first-best policy, the Full Optimum where one assumes
that the policy maker has perfect pricing instruments available. As one would expect, the model shows that the greatest reduction
in traffic level and external costs would occur if it were possible to introduce a highly differentiated and sophisticated
pricing system. Increased taxation on fuel is not an efficient policy as it does not address the marginal external costs of
congestion in a way that time-differentiated road-use pricing would. The results from testing of the different measures are
interesting particularly those relating to parking and the way in which residents within the CBD and commuters to the CBD
are dealt with.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
989.
Mark T. Lusk Young-Kook Lee Herng-Jeng Jou William H. Elliott Gerard M Ludtka . Materials Science Program Division of Engineering Colorado School of Mines Golden CO. U.S. . Questek Innovations LCC Maple Avenue Evanston IL U.S. 《上海交通大学学报(英文版)》2000,(1)
QuanitativelyaccuratePredictionsofquenchinduceddistOnionandresidualstressrelyontheabilitytopredictthemicrosthectUralevolUtionthroughOutthequenchProcess.InlowaIloysteels,cUrrenresearchMshavefOcusedontheformationldneticsoffetrite,pearlite,bainiteandmartensite.However,temPeringcanhavealargeinfluenceondistOnionandresidualstrCss,andeffortstoaccountforthislagbehindthemodelingofthePrimnyphasetransihons.AsafirststeptowardsaccountingfortemPerillg,wehavedevelOpedanintemalstatevariablemodelthatuses… 相似文献
990.
In the globalization era, lean initiatives and environmental management systems are increasingly implemented in the automotive industry. The aim of this report is to investigate and perform structural analysis of Lean Six Sigma (LSS) and Organizational Performance (OP). Data were obtained from 252 top management leaders in the Malaysian automotive industry. This report presents the results of the Exploratory Factor Analyses (EFA), Confirmatory Factor Analysis (CFA), and reliability analysis, which are empirically verified and validated. A set of assessment measurements of LSS and OP is expected to be suitable for their characteristics and improve their competitiveness. Thus, the main objective of the analysis was to provide additional insight into the relationship between LSS and OP by examining the effects of ISO 14001 certification as a moderator. The results indicate that ISO 14001 certification does not significantly moderate the relationship between LSS and OP in the Malaysian automotive industry. However, the OP values for ISO 14001 certified companies are higher than those without ISO 14001 certification. 相似文献