• Title/Summary/Keyword: Air transport

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Energy Efficiency and CO2 Emissions of the Transportation System of Kazakhstan: A Case of Almaty

  • Yessekina, Aiman;Urpekova, Amina
    • The Journal of Asian Finance, Economics and Business
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    • v.2 no.3
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    • pp.41-46
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    • 2015
  • Energy saving in the transport sector in the framework of the annual growth of energy consumption, the degree of negative impact on the environment and the amount of harmful emissions are becoming increasingly important. The article considers the world tendencies of energy consumption in transportation sector and emphasizes its dependency from oil. Also article describes the dynamics of energy use and CO2 emissions from transport of city Almaty. In conclusion authors identify a number of problems in the transport sector, which hinder the implementation of energy efficiency measures and measures to reduce CO2 emissions.

Flame Behaviors of Counterflow Nonpremixed Flame Perturbed by a Vortex (와동에 의해 교란된 대향류 비예혼합화염의 화염거동)

  • Oh, Chang-Bo;Lee, Chang-Eon
    • 한국연소학회:학술대회논문집
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    • 2004.06a
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    • pp.57-63
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    • 2004
  • A two-dimensional direct numerical simulation was performed to investigate the flame behaviors of $CH_4/N_2$-Air counterflow nonpremixed flame interacting with a single vortex. The detailed transport properties and a modified 16-step augmented reduced mechanism based on Miller and Bowman's detailed reaction mechanism are adopted in this calculation. The results showed that an initially flat stagnation plane, on which an axial velocity was zero, was deformed into a complex-shaped plane, and an initial stagnation point was moved far away from a vortex head when the counterflow field was perturbed by the vortex. It was noted that the movement of stagnation point could alter the species transport mechanism to the flame surface. It was also identified that the altered species transport mechanism affected the distributions of the mixture fraction and the scalar dissipation rate.

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Magnetically levitated transport system for a controller-free carrier (제어기 무장착 운송대를 위한 선형운동 자기부상 운송시스템)

  • Son, Yeong-Uk;Park, Gi-Hwan
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.12
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    • pp.2196-2208
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    • 1997
  • In this work, a magnetic levitation (maglev) system is developed to transport a wafer between semiconductor fabrication process modules in clean rooms to take advantages of eliminating particle and oil contamination that normally exist in conventional transport systems due to contact motion of mechanical components. A main feature of the maglev system developed in this work is that a controller and power supplying part are not mounted on the moving carrier but on the stationary track, which is defined a controller-free carrier, to reduce carrier's weight. Iron-core electromagnets and irons are used for levitation, and air-core electromagnets and permanent magnets are used for stabilization. Analysis, design, and modeling of the magnetically levitated transport system are presented. The performance of the maglev system is experimentally demonstrated.

An experimental study on the effects of an inserted coil on flow patterns and heat transport performances for a horizontal rotating heat pipe (수평 회전 히트파이프에서 내부 삽입 코일이 유동 형태 및 열전달 성능에 미치는 영향에 대한 실험 연구)

  • 이진성;김철주;김선주;문석환
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.10 no.6
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    • pp.763-772
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    • 1998
  • The effects of an inserted coil on flow patterns and heat transport performance for a horizontal rotating heat pipe have been studied experimentally. Especially, the present study is to see an internally inserted helical coil inside a RHP would lead to the same kind of results as internal fins. Visualization test conducted for an acryl tube, charged water with at a volumetric rate of 20%. When the flow kept pool regime at a low RPM(less than 1,000 RPM), the movement of coil forced the water to flow in axial direction. But this pumping effect of coil disappeared, when the pool regime changed to annular one which could be created by increasing RPM. The pumping effects for RHP with an inserted coil resulted enhancement both in condensation heat transfer coefficient and heat transport limitation, as obtained in case of using internal fins. But all these effects became negligible in the range of higher RPM(above 1,000∼1,200) with the transition of flow regime to annular flow.

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Theoretical and Experimental Evaluation of R502 Alternatives in Low Temperature Applications (저온용 R502 대체 냉매의 이론 및 실험적 평가)

  • Kwon, S.L.;Park, Y.B.;Jung, D.S.;Kim, C.B.;Kang, D.J.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.4
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    • pp.654-666
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    • 1995
  • R502 has been extensively used as a working fluid in transport refrigerating vehicles and low temperature refrigerating machines but is to be phased out by the end of 1995 due to ozone layer depletion problem. In this study, both theoretical cycle analysis and experiments were carried out to examine the best substitutes for R502. Theoretical results indicate that the alternatives available in the market today may replace R502 without significant changes in the system without suction line heat exchanger(SLHX). When the system contains a SLHX, however, COPs of the alternatives increase up to approximately 15~20% than those without the SLHX. But simultaneously, the discharge temperatures of the compressor also increrease significantly with the SLHX. Actual test results obtained from the experiment with a transport vehicle's refrigerator indicate the similar trend as those of the theoretical results. Especially, HFCs and their mixtures show lower discharge temperature than those of R502, which is one of the desirable features. Further research is needed to study the effect of the SLHX on the performance of the real machine as well as on the oil return for reliability of the system.

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The Preliminary Analysis of Introducing 500 km/h High-Speed Rail in Korea

  • Lee, Kwang-Sub;Eom, Jin Ki;Lee, Jun;Moon, Dae Seop
    • International Journal of Railway
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    • v.6 no.1
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    • pp.26-31
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    • 2013
  • Following the success of the KTX (Korea's first high-speed rail system) with a maximum operating speed of 300 km/h opened in 2004, experts in Korea started a research on the development of key technologies for high-speed rail (HSR) with a top speed of 500 km/h. This paper is a preliminary analysis of the research. It first reviews HSR experiences around the world, in terms of traffic and economic impacts of HSR, and presents a preliminary analysis of 500 km/h HSR in Korea. It is estimated that introduction of 500 km/h HSR with a 54% of travel time reduction will increase HSR passengers to about 9.8 million (about 78% of market share) between Seoul and Busan. It is a 23% of growth compared to the base scenario. Along with conventional rail passengers, air passengers are expected to be significantly impacted by the 500 km/h HSR. As a function of HSR travel time, the estimated market shares of both KTX and 500 km/h HSR compared to air are very comparable with previous international experiences. Based on the forecasted traffic, estimated total benefits are $758 million per year.

Beyond the Quality of Service: Exploring the Evaluation Criteria of Airlines

  • Wang, Ray
    • Industrial Engineering and Management Systems
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    • v.13 no.2
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    • pp.221-230
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    • 2014
  • With the progress and prosperity of commerce and industry, time and money increasingly form an equal partnership. Using air carriers to shorten the round-trip time has become an important choice for many people in the tourism process. Faced with increasing competition within the aviation service environment, airline evaluation criteria and the requirements of customers are gradually dominating the evaluation mechanism for air transport service quality. Over the past few years, attention on the transport quality of service has been primarily focused more on land-based transport, and less on the relevant evaluation criteria of airlines. Many studies have shown that quality of service will directly affect customer satisfaction, resulting in the fact that good quality aviation services have become increasingly important. Therefore, in practical industrial operations with limited resources, there is an urgent need to delve into the assessment guidelines that have an impact on customers when they choose an airline, which can be used as a basis for improving customer satisfaction. Through a literature review and a reliability and validity analysis, this study summarized 19 evaluation criteria, using the purposive sampling method and the decision laboratory method (DEMATEL). In addition, this study viewed the causal relationship between the evaluation criteria and the degree of association as a continuing project for airlines. This study selected appropriate empirical samples from two domestic airlines. The conclusions may provide recommendations for all airlines.

A Study on the Liability Risk of Air Cargo Carrier (항공화물운송인의 책임부담위험에 관한 연구)

  • Kwak, Bong-Hwan;Kang, Dong-Yoon;Ham, Young-Jin
    • International Commerce and Information Review
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    • v.12 no.2
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    • pp.385-405
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    • 2010
  • The purpose of this study is to investigate liability risk of air cargo carrier and suggests ideas for solving problems which could be happen to air transporters on the future. because of Air transport remains one of the world's fastest growing and most important industries. And important treaties and contracts specifying transporters' responsibility regarding big scale aircraft accidents are such as Warsaw Convention in 1929, Hague Protocol in 1955, Montreal Convention in 1999. The Montreal Convention, formally the Convention for the Unification of Certain Rules for International Carriage, is a treaty adopted by Diplomatic meeting of ICAO member states in 1999. It amended important provisions of the Warsaw Convention's concerning compensation for the victims of air disasters. In conclusion, suggests to the method of air cargo security and cargo legal liability insurance which is for air cargo carrier's risk management.

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A Study on simulation analysis of UVGI air sterilizer installation in a car for microbiological safety (미생물 안전을 위한 승용차 실내 UVGI 살균기 설치에 관한 시뮬레이션 연구)

  • Choi, Sang-Gon
    • Journal of the Korea Safety Management & Science
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    • v.16 no.3
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    • pp.279-287
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    • 2014
  • The recent rise in SARS and bird flu infections around the world has raised the interest in studying the habits of air borne pathogens such as germs and viruses. In this study, simulations were carried out to predict the performance of UVGI air sterilizer at preventing airborne infections inside a car, based on the installation position and the removing effect of the UVGI air sterilizer. Simulation results showed that the UVGI air sterilizer was most effective when located at the rear side of the front seats. It was also showed that when the out-air mode and the UVGI air sterilizer were set to the highest capacity, the microbial safety levels were maintained in a car for 21 hours.

A Study on the Limitations of Trade Terms in the Situtations of Kobe Earthquake -with a Special Reference to Marine Insurance- (고배대지진에 기인한 정형거래조건의 문제점)

  • 강진욱
    • The Journal of Information Technology
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    • v.1 no.2
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    • pp.15-24
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    • 1998
  • C.I.F. and F.O.B. contracts are the chief terms used in international trade contracts. But, in recently, the multimodal transport which is based on the containerization and the improvement of air transport has been grown gradually, Regardless of theese change in international trade environment, most of the contract of sale is made by C.I.F. and F.O.B. contracts which are based on the traditional port to port transport. In other words, there are some limitation in terms of legal base in which traditional C.I.F. and F.O.B. contract is applied to the changed environment. Especially, problems arised in marine insurance which export by F.O.B. trade terms. Therefore, when the parties of the contracts of sale make an sale contracts by using the container ship and Multimodal Transport, they should use the F.C.A. and C.I.P. contracts Instead of F.O.B. and C.I.F. contracts for the transport of goods. And parties of the contracts of sale need to gain a better understanding of the characteristic of F.C.A. and C.I.P. terms and the problem of the F.C.A. and C.I.P. contracts used in the performance on international multimodal transport.

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