• Title/Summary/Keyword: Air transport

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Improving Traffic Infrastructure in a Developing Country: An Investigation into the Usage of Public Bus Transport in Malaysia

  • Soh, Keng Lin;Wong, Wai Peng;Chong, Chu Le;Hiew, Yan Hwan
    • Industrial Engineering and Management Systems
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    • v.13 no.2
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    • pp.172-184
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    • 2014
  • Economic growth with rising household income has put more vehicles on the roads worsening traffic congestion, road accidents, and air and noise pollution. This situation is further aggravated by the potential working population who choose to drive to work instead of taking public transportation. Public bus transport (PBT) plays an important role in alleviating these problems. PBT is underutilized in Malaysia, and there is an opportunity to increase ridership without substantial investment. Therefore, this study was conducted to investigate the factors that influence the use of PBT in Malaysia. The data were collected using structured questionnaires from 400 respondents. The results of the analysis show that the twin factors consisting of perceived satisfaction of and perceived importance by users towards safety and comfort of facilities and services offered by PBT are significantly related to intention to use those services. The satisfaction of availability of season tickets, the importance of reliability of bus schedule and time table, and the importance of ticket pricing are also significant. By providing insights for both public bus operators and the government, this paper contributes to mitigate the underutilization of PBT in Malaysia and the consequences of putting more vehicles on the roads. From the theory perspective, this paper also contributes by extending the theory of reasoned-action to transportation studies.

Lifting off simulation of an offshore supply vessel considering ocean environmental loads and lifting off velocity

  • Jeong, Dong-Hoon;Roh, Myung-Il;Ham, Seung-Ho
    • Ocean Systems Engineering
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    • v.5 no.3
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    • pp.181-198
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    • 2015
  • An OSV (Offshore Support Vessel) is being used to install a structure which is laid on its deck or an adjacent transport barge by lifting off the structure with its own crane, lifting in the air, crossing splash zone, deeply submerging, and lastly landing it. There are some major considerations during these operations. Especially, when lifting off the structure, if operating conditions such as ocean environmental loads and lifting off velocity are not suitable, the collision can be occurred due to the relative motion between the structure and the OSV or the transport barge. To solve this problem, this study performs the physics-based simulation of the lifting off step while the OSV installs the structure. The simulation includes the calculation of dynamic responses of the OSV and the structure, including the collision detection between the transport barge and the structure. To check the applicability of the physics-based simulation, it is applied to a problem of the lifting off step by varying the ocean environmental loads and the lifting off velocity. As a result, it is confirmed that the operability of the lifting off step are affected by the conditions.

Optimization of structural elements of transport vehicles in order to reduce weight and fuel consumption

  • Kovacs, Gyorgy
    • Structural Engineering and Mechanics
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    • v.71 no.3
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    • pp.283-290
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    • 2019
  • In global competition manufacturing companies have to produce modern, new constructions from advanced materials in order to increase competitiveness. The aim of my research was to develop a new composite cellular plate structure, which can be primarily used for structural elements of road, rail, water and air transport vehicles (e.g. vehicle bodies, ship floors). The new structure is novel and innovative, because all materials of the components of the newly developed structure are composites (laminated Carbon Fiber Reinforced Plastic (CFRP) deck plates with pultruded Glass Fiber Reinforced Plastic (GFRP) stiffeners), furthermore combines the characteristics of sandwich and cellular plate structures. The material of the structure is much more advantageous than traditional steel materials, due mainly to its low density, resulting in weight savings, causing lower fuel consumption and less environmental damage. In the study the optimal construction of a given geometry of a structural element of a road truck trailer body was defined by single- and multi-objective optimization (minimal cost and weight). During the single-objective optimization the Flexible Tolerance Optimization method, while during the multi-objective optimization the Particle Swarm Optimization method were used. Seven design constraints were considered: maximum deflection of the structure, buckling of the composite plates, buckling of the stiffeners, stress in the composite plates, stress in the stiffeners, eigenfrequency of the structure, size constraint for design variables. It was confirmed that the developed structure can be used principally as structural elements of transport vehicles and unit load devices (containers) and can be applied also in building construction.

Annealing Temperature of Nickel Oxide Hole Transport Layer for p-i-n Inverted Perovskite Solar Cells (P-I-N 역구조 페로브스카이트 태양전지 응용을 위한 Nickel oxide 홀전달층의 열처리 온도 연구)

  • Gisung Kim;Mijoung Kim;Hyojung Kim;JungYup Yang
    • Current Photovoltaic Research
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    • v.11 no.4
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    • pp.103-107
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    • 2023
  • A Nickel oxide (NiOx) thin films were prepared via sol-gel process on a transparent conductive oxide glass substrate. The NiOx thin films were spin-coated in ambient air and subsequently annealed for 30 minutes at temperatures ranging from 150℃ to 450℃. The structural and optical characteristics of the NiOx thin films annealed at various temperatures were measured using X-ray diffraction, field emission scanning electron microscopy, and ultraviolet-visible spectroscopy. After optimizing the NiOx coating conditions, perovskite solar cells were fabricated with p-i-n inverted structure, and its photovoltaic performance was evaluated. NiOx thin films annealed at 350℃ exhibited the most favorable characteristics as a hole transport layer, resulting in the highest power conversion efficiency of 17.88 % when fabricating inverted perovskite solar cells using this film.

Analysis of the Changesin PM2.5 Concentrations using WRF-CMAQ Modeling System: Focusing on the Fall in 2016 and 2017 (WRF-CMAQ 모델링 시스템을 활용한 PM2.5 농도변동 원인 분석: 2016년과 2017년의 가을철을 중심으로)

  • Nam, Ki-Pyo;Lim, Yong-Jae;Park, Ji-Hoon;Kim, Deok-Rae;Lee, Jae-Bum;Kim, Sang-Min;Jung, Dong-Hee;Choi, Ki-Chul;Park, Hyun-Ju;Lee, Han-Sol;Jang, Lim-Seok;Kim, Jeong-Soo
    • Journal of Environmental Impact Assessment
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    • v.27 no.2
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    • pp.215-231
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    • 2018
  • It was analyzed to identify the cause of $PM_{2.5}$ concentration changes for the fall in 2016 and 2017 in South Korea using ground measurement data such as meterological variables and $PM_{2.5}$, AOD from GOCI satellite, and WRF-CMAQ modeling system. The result of ground measurement data showed that the $PM_{2.5}$ concentrations for the fall in 2017 decreased by 12.3% ($3.0{\mu}g/m^3$) compared to that of 2016. The difference of $PM_{2.5}$ concentrations between 2016 and 2017 mainly occurred for 11 Oct. - 20 Oct. (CASE1) and 15 Nov. - 19 Nov. (CASE2) when weather conditions were difficult to long-range transport from foreign regions and favored atmospheric ventilation in 2017 compared to 2016. Simulated $PM_{2.5}$ concentrations in 2017 decreased by 64.0% ($23.1{\mu}g/m^3$) and 35.7% ($12.2{\mu}g/m^3$) during CASE1 and CASE2, respectively. These results corresponded to the changes in observed $PM_{2.5}$ concentrations such as 53.6% for CASE1 and 47.8% for CASE2. It is implied that the changes in weather conditions affected significantly the $PM_{2.5}$ concentrations for the fall between 2016 and 2017. The contributions to decreases in $PM_{2.5}$ concentrations was assessed as 52.8% by long-range transport from foreign regions and 47.2% by atmospheric ventilation effects in domestic regions during CASE1, whereas their decreases during CASE2 were affected by 66.4% from foreign regions and 33.6% in domestic regions.

Liability of the Compensation for Damage Caused by the International Passenger's Carrier by Air in Montreal Convention (몬트리올조약에 있어 국제항공여객운송인의 손해배상책임)

  • Kim, Doo-Hwan
    • The Korean Journal of Air & Space Law and Policy
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    • v.18
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    • pp.9-39
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    • 2003
  • The rule of the Warsaw Convention of 1929 are well known and still being all over the world. The Warsaw Convention is undoubtedly the most widely accepted private international air law treaty with some 140 countries. In the international legal system for air transportation, the Warsaw Convention has played a major role for more than half century, and has been revised many times in consideration of the rapid developments of air high technology, changes of social and economic circumstances, need for the protection of passengers. Some amendments became effective, but others are still not effective. As a result, the whole international legal system for air transportation is at past so complicated and tangled. However, the 'Warsaw system' consists of the Warsaw Convention of 1929 the Guadalajara Convention of 1961, a supplementary convention, and the following six protocols: (1) the Hague Protocol of 1955, (2) the Guatemala Protocol of 1971, (3) the Montreal Additional Protocols, No.1, (4) the Montreal Additional Protocol No.2, (5) the Montreal Additional Protocol No.3, and (6) the Montreal Additional Protocol No.4. of 1975. As a fundamental principle of the air carrier's liability in the international convention and protocols, for instance in the Warsaw Convention and the Hague Protocol, the principle of limited liability and a presumed fault system has been adopted. Subsequently, the Montreal Inter-carrier Agreement of 1966, the Guatemala City Protocol, the Montreal Additional Protocol No.3, and the Montreal Additional Protocol No. 4 of 1975 maintained the limited liability, but substituted the presumed liability system by an absolute liability, that is, strict liability system. The Warsaw System, which sets relatively low compensation limits for victims of aircraft accidents and regulates the limited liability for death and injury of air passengers, had become increasingly outdated. Japanese Airlines and Inter-carrier Agreement of International Air Transport Association in 1995 has been adopted the unlimited liability of air carrier in international flight. The IATA Inter-Carrier Agreement, in which airlines in international air transportation agree to waive the limit of damages, was long and hard in coming, but it was remarkable achievement given the political and economic realities of the world. IATA deserves enormous credit for bringing it about. The Warsaw System is controversial and questionable. In order to find rational solution to disputes between nations which adopted differing liability systems in international air transportation, we need to reform the liability of air carriers the 'Warsaw system' and fundamentally, to unify the liability system among the nations. The International Civil Aviation Organization(ICAO) will therefore reinforce its efforts to further promote a legal environment that adequately reflects the public interest and the needs of the parties involved. The ICAO Study Group met in April, 1998, together with the Drafting Committee. The time between the "Special Group on the Modernization and Consolidation of the 'Warsaw system'(SGMW)" and the Diplomatic Conference must be actively utilized to arrange for profound studies of the outstanding issues and for wide international consultations with a view to narrowing the scope of differences and preparing for a global international consensus. From 11 to 28 May 1999 the ICAO Headquarters at Montreal hosted a Diplomatic Conference convened to consider, with a view to adoption, a draft Convention intended to modernize and to integrate replace the instruments of the Warsaw system. The Council of ICAO convened this Conference under the Procedure for the Adoption of International Conventions. Some 525 participants from 121 Contracting States of ICAO attended, one non-contracting State, 11 observer delegations from international organizations, a total of 544 registered participants took part in the historic three-week conference which began on 10 May. The Conference was a success since it adopted a new Convention for the Unification of Certain Rules for International Carriage by Air. The 1999 Montreal Convention, created and signed by representatives of 52 countries at an international conference convened by ICAO at Montreal on May 28, 1999, came into effect on November 4, 2003. Representatives of 30 countries have now formally ratified the Convention under their respective national procedures and ratification of the United States, which was the 30th country to ratify, took place on September 5, 2003. Under Article 53.6 of the Montreal Convention, it enters into force on the 60th day following the deposit of the 30th instrument of ratification or acceptation. The United States' ratification was deposited with ICAO on September 5, 2003. The ICAO have succeeded in modernizing and consolidating a 70-year old system of international instruments of private international law into one legal instrument that will provide, for years to come, an adequate level of compensation for those involved in international aircraft accidents. An international diplomatic conference on air law by ICAO of 1999 succeeded in adopting a new regime for air carrier liability, replacing the Warsaw Convention and five other related legal instruments with a single convention that provided for unlimited liability in relation to passengers. Victims of international air accidents and their families will be better protected and compensated under the new Montreal Convention, which modernizes and consolidates a seventy-five year old system of international instruments of private international law into one legal instrument. A major feature of the new legal instrument is the concept of unlimited liability. Whereas the Warsaw Convention set a limit of 125,000 Gold Francs (approximately US$ 8,300) in case of death or injury to passengers, the Montreal Convention introduces a two-tier system. The first tier includes strict liability up to l00,000 Special Drawing Rights (SDR: approximately US$ 135,000), irrespective of a carrier's fault. The second tier is based on presumption of fault of a carrier and has no limit of liability. The 1999 Montreal Convention also includes the following main elements; 1. In cases of aircraft accidents, air carriers are called upon to provide advance payments, without delay, to assist entitled persons in meeting immediate economic needs; the amount of this initial payment will be subject to national law and will be deductable from the final settlement; 2. Air carriers must submit proof of insurance, thereby ensuring the availability of financial resources in cases of automatic payments or litigation; 3. The legal action for damages resulting from the death or injury of a passenger may be filed in the country where, at the time of the accident, the passenger had his or her principal and permanent residence, subject to certain conditions. The new Montreal Convention of 1999 included the 5th jurisdiction - the place of residence of the claimant. The acceptance of the 5th jurisdiction is a diplomatic victory for the US and it can be realistically expected that claimants' lawyers will use every opportunity to file the claim in the US jurisdiction - it brings advantages in the liberal system of discovery, much wider scope of compensable non-economic damages than anywhere else in the world and the jury system prone to very generous awards. 4. The facilitation in the recovery of damages without the need for lengthy litigation, and simplification and modernization of documentation related to passengers. In developing this new Montreal Convention, we were able to reach a delicate balance between the needs and interests of all partners in international civil aviation, States, the travelling public, air carriers and the transport industry. Unlike the Warsaw Convention, the threshold of l00,000 SDR specified by the Montreal Convention, as well as remaining liability limits in relation to air passengers and delay, are subject to periodic review and may be revised once every five years. The primary aim of unification of private law as well as the new Montreal Convention is not only to remove or to minimize the conflict of laws but also to avoid conflict of jurisdictions. In order to find a rational solution to disputes between nations which have adopted differing liability systems in international air transport, we need fundamentally to reform their countries's domestic air law based on the new Montreal Convention. It is a desirable and necessary for us to ratify rapidly the new Montreal Convention by the contracting states of lCAO including the Republic of Korea. According to the Korean and Japanese ideas, airlines should not only pay compensation to passengers immediately after the accident, but also the so-called 'condolence' money to the next of kin. Condolence money is a gift to help a dead person's spirit in the hereafter : it is given on account of the grief and sorrow suffered by the next of kin, and it has risen considerably over the years. The total amount of the Korean and Japanese claims in the case of death is calculated on the basis of the loss of earned income, funeral expenses and material demage (baggage etc.), plus condolence money. The economic and social change will be occurred continuously after conclusion of the new Montreal Convention. In addition, the real value of life and human right will be enhanced substantially. The amount of compensation for damage caused by aircraft accident has increased in dollar amount as well as in volume. All air carrier's liability should extend to loss of expectation of leisure activities, as well as to damage to property, and mental and physical injuries. When victims are not satisfied with the amount of the compensation for damage caused by aircraft accident for which an airline corporation is liable under the current liability system. I also would like to propose my opinion that it is reasonable and necessary for us to interpret broadly the meaning of the bodily injury on Article 17 of the new Montreal Convention so as to be included the mental injury and condolence. Furthermore, Korea and Japan has not existed the Air Transport Act regulated the civil liability of air carrier such as Air Transport Act (Luftverkehrsgestz) in Germany. It is necessary for us to enact "the Korean Air Transport Contract Act (provisional title)" in order to regulate the civil liability of air carrier including the protection of the victims and injured persons caused by aircraft accident.

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Liability of Air Carrier and its Legislative Problems in China : Some proposals for its Amendments (중국 항공운송법의 현황 및 주요내용과 앞으로의 전망 : 항공운송인의 책임을 중심으로)

  • Li, Hua
    • The Korean Journal of Air & Space Law and Policy
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    • v.26 no.1
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    • pp.147-176
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    • 2011
  • China is experiencing rapid economic development and the volume of air passengers and cargo transportation has increased significantly in recent years. To the contray, the regulations on liability of air carrier in china fall behind and are not sufficiently applicable in disputes. Their lack of sufficient protection for air passenger's interests became obstructive factor for further developments of Chinese air transportation industry. The legal system of air carrier's liability mainly consists of the contents as followed. The liability period, the scope of liability, amount of compensation for damage, limitation of liability, liability exemption of air carrier, jurisdiction, limitation of action, applicable law etc. Laws and rules concerning these issues are regulated in Civil Aviation Law and regulations published by Civil Aviation Administration of China. This article described the main contents of air carrier's liability and examined the legislative problems in their applications in real cases. In order to solve the legal problems on the air carrier's liability and disputes between wrongdoers and survivors etc, it is necessary and desirable for china to amend revelvant provisions. One of my proposals is to raise the amount of compensation limitation for damage. And I also would like to suggest that Civil Aviation Law should treat international and domestic transportation equally on the limitation of compensation for air carrier's liability. China has also acceded to the Montreal Convention of 1999 on July 31, 2005. This is an effort to make the law of air carriage unified worldwide through various international conventions to achieve conformity between rules of international air carriage and that of Chinese domestic aircarriage. Furthermore, there should be additional detailed implementation rules for air carrier to assume liability for the losses to passengers, baggage or cargoes caused by delays in the air transport. Significant clarifications are also needed for provisions concerning whether and how air carrier assume liability for moral damage caused by accident.

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An Acid Deposition engineering Model (공학적 산침적 모델에 관한 연구)

  • 조석연
    • Journal of Korean Society for Atmospheric Environment
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    • v.9 no.E
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    • pp.390-396
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    • 1993
  • An acid deposition Engineering Model was developed by parameterizing the role of organics in the photochemistry and by simplifying liquid phase processes. This Engineering Model concept was implemented onto the Sulfur Transport Eulerian Model II(STEM II). The Engineering Model version of the STEM(STEM-ENG) saves the CPU time over 50 times and produces the upper and lower limit values prodicted by the original STEM II. These limits obtained by the STEM-ENG can be used to estimate the importance of organics in acid and O3 production. The STEM-ENG with 30,000 grid points can be run on any recent PCs to give a quick assessment of air quality.

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A Study on the Prediction of SO2 Concentration in local Circulation of Mesoscale (중규모 국지순환에서 이산화황의 농도예측에 관한 연구)

  • Lee, Hwa-Woon;Kim, Yoo-Keun;Jang, Eun-Suk
    • Journal of Environmental Science International
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    • v.5 no.3
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    • pp.277-284
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    • 1996
  • The Characteristics of atmospheric flow and dispersion of air pollutants in the mountainous coastal area were studied using two-dimensional model by the combination of land-sea breezes and transport. The pollutants emitted into the simulated wind field in considering with the mesoscale local circulations. The typical effects of land-sea breezes and tophography of coastal area on the dispersion are discussed in detail, and the model is proved as an useful tool to pridict real time pollutant transport by the results of application studies in Pusan, Korea where the urbanized coastal area with mountainous topography. It was found that sulfur dioxide ($SO_2$) are differently transported and concentrated as going inland by the influence of the sea breeze with topographic changes. Key words : land-sea breezes, sulfur dioxide, dispersion, coastal area.

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Analysis of the Laminar Lifted Flame Structure (층류 부상화염 구조의 해석)

  • Kim, Hoojoong;Kim, Yongmo;Kim, Sewon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.9
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    • pp.1098-1105
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    • 1999
  • A lifted laminar flame structure has been numerically analyzed. The present study employs the physical submodels including the detailed chemical kinetics and the variable transport properties. The validation cases Include a lifted laminar CH4/air flame with a central diluted fuel jet and a surrounding fuel-lean coflow. Numerical results indicate the present approach successfully simulate the detailed structure and mechanism of the triple flame in the lifted laminar methane flame.