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        검색결과 293

        281.
        2004.03 KCI 등재 서비스 종료(열람 제한)
        The purpose of this study is to analyze the characteristics of riverbed variation due to the sediment protection weir located on the estuary of the main stream of Taehwa river using 1-D finite difference model, HEC-6 model, and the followings are the results of estimating sediment transport rate, amount of scour or deposition, and accumulated amount of deposit according to before and after of the sediment protection weir removal with various flow rates in the channel. Ackers-White transport function produced the greatest sediment transport rate while Meyer-Peter showed the smallest sediment transport rate at the most down stream area of the watershed through the sediment transport rate analyses for various flow rates according to the existence or nonexistence of the sediment protection weir. Toffaleti's and Colby transport function were closest to the average value, and the difference among the results of the sediment transport functions showed up to 8~9 times. Duboy’s transport function produced the greatest riverbed variation while Toffaleti’s showed the smallest variation through the riverbed variation analyses according to the existence or nonexistence of the sediment protection weir. Yang’s was closest to the average value, and the difference among the results of the riverbed variation analyses ranged from 1.4 times to 11 times. It is thought that a sediment transport function must be selected very carefully with respect to the criteria of sediment yield estimation because the analysis results of the sediment transport rate and riverbed variation according to flow rates showed significant differences among the sediment transport functions, and the differences of sediment transport rate and riverbed variation according to the various sediment transport functions decreased as the flow rate increased.
        282.
        2001.03 서비스 종료(열람 제한)
        The purpose of this study is to improve the strategies for transportation systems of container cargoes in Busan port. Therefore, container cargoes forecasting is done through logistic methods based on past trends. In 2011, container cargoes demand was forecasted 8.791 million TEU(T/S including 12.559 million TEU). In order to improve transportation systems of container cargoes, the conclusions of this study can be summarized as follows ; \circled1 port facilities expansion, \circled2 diversity of container transport modes, \circled3 make up ICD and exclusive container roads, \circled4 the second Seoul-Busan Expressway.
        283.
        2000.09 KCI 등재 서비스 종료(열람 제한)
        Service is the source of firm's competitive advantage in recent years. The importance of service quality in any service industry doesn't need to be disputed. Customers have expected the improvement of the quality of service they receive ,so providers are struggling to meet these expectations. This study aims at finding factors of service quality in passenger transportation. An empirical investigation and the measurement on the perceived Service Quality by customers in the passenger transportation system was carried out. The purpose of this study is to clarify the factors of service quality on the basis of service marketing concept. In order to fulfill the objectives, this paper combines research tools that include both empirical study and documentary research. Data was gathered from 239 passengers by the use of questionnaire. In this study, the established hypotheses were generated on the basis of the service quality evaluation (SERVQUAL) model. Research findings through empirical test are as follows. First, five service quality dimensions in passenger transportation are identical to SERVQUAL dimensions defined by Parasuraman, Zeithaml, and Berry in 1988. Second, demographic segments such as gender and age don't have significant different dimension of service quality. Third, there is no significant difference between groups by experiences such as price level, abroad tour and vehicle type in determinants of transportation service quality.
        284.
        2000.09 서비스 종료(열람 제한)
        Today the pedestrian-related problems a key subject requiring the attention of the traffic engineers for improving the transportation system. Particularly in urban and CBD locations, the pedestrian presents an element of sharp conflict with vehicular traffic. Therefore pedestrian movements must be studied for the purpose of providing guideline for the design and operation of walking transportation systems. This paper is to address the characteristics of walking transportation in a big city. Especially the focuses are emphasized on the ratio occupied by pedestrian traffic among the whole unlinked trips in a city and walking time. The data for analysis are collected in Seoul metropolitan city through sampling 1,006 citizens. Compared with other similar research works this paper utilized diversified tools to acquire more useful results. Finally, policy directions for pedestrian environment improvement were suggested.
        285.
        1999.12 서비스 종료(열람 제한)
        Today freeway is thought to be a very important transportation facility carrying tremendous traffic flow as the main corridor within the area of between the areas. However freeway is experiencing severe congestion and accidents by increased entrance ramp flow especially at peak time period. Ramp meters on the freeway entrance ramps that supply traffic to the freeway in a measured or appropriately regulated amount are needed for alleviating freeway congestion. Because ramp meters can be operated to discharge traffic at a measured or regulated rate thus maintaining more uniform speed on the mainline section maximizing the throughput to the freeway within the capacity of a downstream bottleneck and reducing the congestion related accidents. Thus the objectives in this study were to analyze the traffic characteristics on the freeway I-94 with ramp metering system before/after ITS technology in Detroit (Michigan) area compare shifts of the traffic characteristics on the freeway I-94 before/after ITS technology and finally suggest a better ramp metering strategy for the freeway system The following results were obtained: i)Flow occupancies and speeds on the mainline merge section of freeway were shown to be a big difference depending on the peak periods areas and directions based on the distribution of traffic flow characteristics on the freeway. ii)Reduced speed was shown to be more than 5 mph and ramp flow was also shown to be more than 240 vph at peak periods if there was the ramp metering system constructed on the freeway. iii)Ramp metering system was shown to be optimally operated on the freeway if ramp flow could be maximized within the range of over 900 vph and reduced occupancy could be also maximized by no more than 2 percent at peak periods. iv)The average flows on the freeway after the ITS technology were shown to be a decrease of over 20% depending on the peak periods areas and directions when compared with those flow on the freeway before the ITS technology. over 20% depending on the peak periods areas and directions when compared with those speeds on the freeway before the ITS technology. vi)The average metering rates on the freeway after the ITS technology were shown to be an increase of over 10% depending on the peak periods areas and directions when compared with those metering rates on the freeway before the ITS technology.
        286.
        1998.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        제주산 감귤의 유통방법에 따른 선도 변화를 조사하고 저온유통의 효과를 검토하였다. 유통 중 성분변화는 상온(17)유통이 저온(5)유통에 비해서 중량감소는 6% 증가, vitamin C는 1.91mg 감소, 당산비는 20% 증가함을 보였다. 상온유통에서 중량감소로 인하여 당산비가 높아져서 (16.11에서 21.75) 감귤의 맛과 선도가 감소된다. 현행 감귤수송은 상온유통을 하고 있으나 고품질 감귤에는 부적합한 것으로 나타나며 고품질 소량생산 지향의
        287.
        1996.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        Most of countries differ from their favors, in Taiwan fruit juice and sweet taste are emphasized while external appearance in Japan. During transportation, movement of the container, fluctuation of temperature, decrease of the fruit freshness and undesirable packing materials tend to decline fruit marketability. For these problems, it is believed that shortening of boarding time by utilization of plate and styro form box for packing, the author believed.
        288.
        1996.06 KCI 등재 서비스 종료(열람 제한)
        The routes of coastal passenger ships are important in the light of both economic and social view point. Islands around the Korean peninsular can be actually dominated by linking them with land by the ships. The service quality of the route is not high enough to satisfy habitants in the islands. The income of the service-users is increasing so that they expect better service in terms of ship's speed and cabin. The reality is not, however, good to motivate ship-owners to replace aged ships with new and large ones. The situation is caused by low passenger-fare and inefficient management. Therefore the fare should be raised and the fare system should be innovated. And the number of passenger ship companies should be reduced from 42 to 20 by merger and acquisition.
        289.
        1991.08 서비스 종료(열람 제한)
        In this study, to identify the ineffectiveness of inter-connected system of cargo volume between the Pusan Port and inland areas and also to make more rational suggestions, the following conclusions were drawn by analyzing Container Cargo Traffic from BCTOC to Off-Dock CY: 1. There existed about 30% to 50% reduction in the container transport times when the container transport vehicles were operated during the off-peak period to alleviate the traffic congestion due to mixed traffic. 2. There appeared to be more economic when Off-Dock DY's scattered around the City of Pusan were unified in one ODCY Unit at YangSan, and the Exclusive Overpass Freeway System for the container transport vehicles were constructed and operated on the existing Urban Freeway from BCTOC ti this ODCY Unit (Expected to make about 230 billions Won in net present value by NPV method).
        290.
        1988.04 KCI 등재 서비스 종료(열람 제한)
        Decision Science or Decision Analysis can be described as a scientific methodolog to provide suitable quantitative information for the decision maker to be able to selected the best feasible alternative on the given decision environment and thus we can say that where there are decision problems, there needs the decision analysis to be applied to them. International shipping is generally said to be the cheapest and most widely used means of transport in international trade and each of the hundreds of seaport. So far as the decision makings in the shipping and port transportation are concerned, of real importance is to understand what the decision problems in each of shipping and port transportation really are and to recognize the meaning of relevance between shipping and seaport in the outworn phrase, that is to say, "The chain is as strong as its weakest link." This paper is intended to present a literature survey on the applied decision analysis to shipping and port transportation problems which have actually been involved in the wide variety of decision environment. At first, the author suggests four divisional framework such as decision analysis in each field of Shipping Economics, Management and Operations of Shipping, Port Economics, and Port Operation and Management, according to the main concern of the decision environment, and then the literature surveys on those four major divisions are described including the problems and solution approaches in each case. The author concludes the paper with the comment on the need of joint research around this area by citing the phrase of "a process of updating the decision makers' intuitions."s' intuitions."quot;
        291.
        1986.06 KCI 등재 서비스 종료(열람 제한)
        Transportation provides an infrastructure vital to economic growth, and it is an integral part of production . As a port is the interface between the maritime transport and domestic transport sectors, it certainly plays a key role in any economic development. Therefore, it is doubtless that inadequacy of a nation's port will depress the level of throughput, to the level where it fails to meet the target set by the national economic planning schemes. Korea is surrounded by the seas and the economic structure of Korea consists of processing trades, so that it cannot be overstated that substantial economy in maritime transport coasts can be achieved through the improvement of the port transport system. This paper treats the transportation process in Pusan Port by Queueing Simulation method, and the reasonable size of Pusan Port is suggested from the point of view of efficiency maximization. The results of the analysis are summarized as follows; 1) the utility rate is 47.91 percents in general piers, 85-52 percents in container piers, and waiting time 5.2hrs, in general piers, 0.8 hrs, in container piers, and the probability of maximum queue length 12 ships in general piers, 2 ships in container piers, and the probability of waiting is 44 percents in general piers, 8 percents in container pier. 2) in general piers, the improvement of app. 30 percents in port capacity is desirable for operating effectively concerning the current arrival rate. By introducing the traffic control ion container piers, there is no apparent necessity of port investment, but I is expected to reduce invisible congestion occurred along the waiting line. 3) On Pusan Port, the optimal utility rate and the optimal arrival rate for reducing waiting time are 3.5 to 4.0(hrs./ship) in general piers, 5.1 to 6.0(hrs./ship) in container piers.
        292.
        1985.10 KCI 등재 서비스 종료(열람 제한)
        The transportation productivity is the throughput of utility per locations of resources and is able to be brought forth by using transportation mode. Therefore, Oil energy is necessary for using the transportation mode that is mainly consisted of four parts trucks, railroad, ship and aircraft, and Oil quantity used for such modes is not respectively same. Noticing Such a Point, the purpsoe of this paper is to reaserch the transportation mode of convertable cargoes and to minimize energy consumption quantity by adopting such a mode. We must ttend to Energy-Intensity, Transportation, Distance and cargo quantity for selecting the transport mode to energy consumption and the minimization of transportation energy consumption is concluded in the next LP Problem. As above mentioned, we can find the solution of Xij by the LP when Xij is transportation cargo per routes, and fullfil the minimization of Energy Consumption.
        293.
        1983.05 KCI 등재 서비스 종료(열람 제한)
        The delay due to congestion has recently attracted widespread attention with the analysis of over-all operation at the port. But, the complexity of the situation is evident in view of the large number of factors which impinge on the considerable end. Queueing theory is applicable to a large scale transportation system which is associated with arrivals of vessels in a large port. The attempt of this paper is to make an extensive analysis of the port transport system and its economic implications from the viewpoint that port is one of the physical distribution facilities and a kind of queueing system which includes ships and cargoes as port customer. By analyzing the real data on the Port of Pusan, it is known that this port can be represented as a set of multi-channel with identical setof Poisson arrival and Erlang service time, and also it is confirmed that the following formula is suitable to calculate the mean delay in this port, namely, W4=σλ(1-σ) eN(σ·N)DN-1(σ·N) where, λ: mean arrival rate μ: mean servicing rate; N: number of servicing channel; σ: utillization rate (λ/Nμ) eN: the Poisson function Coming to grips with the essentials of the cost of delay due to congestion, a simple ship journey cost model is adopted and the operating profit sensitivity to variation in port time is examined, and for purpose of a future development for port princing service the marginal cost is approximately calculated on the basis of queueing theory.