• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.12
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• pp.2319-2326
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• 2007

Recently, various systems are being developed for efficiently assignment and management of such resources as seats of airplane, train, bus, theater, and library. If it occurs the exceed demand for the limited seat resource, the system has much difficulty for the seat resource management and assignment efficiently. The existed allocation and management methods were processed using the centralization management of the limited seat resource. But these methods cannot consider the preference of each user, and these not support the fairness of usage for each person. Accordingly, we design and implement the seat assignment system based on the customer-driven for the seat management in the reading room of library, customer selects directly for the fairness of seat.

• Elastomers and Composites
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• v.56 no.4
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• pp.234-242
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• 2021

The demand for truck bus radial (TBR) tires with enhanced fuel efficiency and wear resistance have grown in recent years. In addition, as the issue of particulate matter and air pollution increases, efforts are being made to reduce the generation of particulate matter. In this study, the properties of epoxidized natural rubber (ENR) containing a silica-friendly functional group were evaluated by considering it as a base rubber and varying the silica ratio in this binary filler system. The results showed that the wear resistance of the NR/BR blend compound decreased as the silica ratio increased. In contrast, the ENR/BR blend compound exhibited an increase in wear resistance as the silica ratio was increased. In particular, the ENR-50/BR blend compound showed the best wear resistance due to the presence of several epoxide groups. Furthermore, we observed that for tan 𝛿 at 60℃, higher epoxide content resulted in the higher T_g of the rubber, indicating a higher tan 𝛿 at 60℃. On the other hand, it was confirmed that increasing the silica ratio decreased the value of tan 𝛿 at 60℃ in all compounds. In addition, we measured the amount of wear particulate matters generated from the compound wear. These measurements confirmed that in the binary filler system, regardless of the filler type, the quantity of the generated wear particulate matters as the filler-rubber interaction increased. In conclusion, the silica filled ENR/BR blend compound exhibited the lowest generation of wear particulate matters.

• Elastomers and Composites
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• v.56 no.4
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• pp.243-249
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• 2021

The demand for truck bus radial (TBR) tires with enhanced fuel efficiency and wear resistance have grown in recent years. In addition, as the issue of particulate matter and air pollution increases, efforts are being made to reduce the generation of particulate matter. In this study, we investigated the effect of varying the content of butadiene rubber (BR) on the properties of the rubber compounds and the amount of particulate matter in the TBR tire tread compound. Furthermore, we utilized carbon black in the NR/BR blend compounds owing to its excellent compatibility, and we used silica in the ENR-25/BR blend compounds because it can interact chemically with epoxide groups. The NR/BR blend compounds and the ENR-25/BR blend compounds were evaluated by varying their BR content between 20 phr and 30 phr. The results showed that the ENR-25/BR blend compounds had superior wear resistance than the NR/BR blend compounds. This was caused by the interaction between silica and ENR. In addition, it was confirmed that the increased wear resistance as the BR content increased. Furthermore, compared to the NR/BR blend compounds, ENR-25/BR blend compounds exhibited a lower tan 𝛿 value at 60℃ because silica was used as filler. This indicates a higher fuel efficiency. The measurement results for wear particulate matter showed that as increasing the BR content resulted in generation of less wear particulate matter. This was caused by the increased wear resistance. Moreover, the ENR-25/BR blend compounds with excellent filler-rubber interaction exhibited lower quantities of generated wear particulate matters as compared to the NR/BR blend compounds.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.1
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• pp.219-232
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• 2023

Mobility services need to change according to the regional characteristics of the target service area. Accordingly, analysis of mobility patterns and characteristics based on Origin-Destination (OD) data that reflect travel behaviors in the target service area is required. However, since conventional methods construct the OD data obtained from the administrative district-based zone system, it is hard to ensure spatial homogeneity. Hence, there are limitations in analyzing the inherent travel patterns of each mobility service, particularly for new mobility service like Demand Responsive Transit (DRT). Unlike the conventional approach, this study applies a data-driven clustering technique to conduct spatial analyses on OD travel patterns of regional mobility services based on reconstructed OD data derived from re-aggregation for original OD distributions. Based on the reconstructed OD data that contains information on the inherent feature vectors of the original OD data, the proposed method enables analysis of the spatial characteristics of regional mobility services, including public transit bus, taxi and DRT.

• Journal of the Korean Society for Railway
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• v.18 no.6
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• pp.630-638
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• 2015

The total number of passengers on the KTX since its construction in 2004 surpassed 500 million in October, 2015. The operation of KTX made it possible to reach anywhere in a country in half a day, which subsequently altered people's lifestyle. As the KTX has become an important mode of transportation, there is a growing interest in the optimal size and location of its stations. Currently, the stations are constructed through public-private partnerships since a sufficient amount of budget is hard to secure only from the public sector; however, because railway stations are traditionally aimed at promoting public interests, an emphasis on the profitability of the private sector could compromise public interests. At this juncture, this study separately computes the number of users based on each of the two primary functions of the stations-as a railway station and as a sales facility-and estimates the numbers of people according to various transportation modes that are taken to access the stations. This estimation is applied to the case of Dongdaegu Station, which will open in 2016. Such an application helps to predict and respond to possible congestion as brought about by the expansion of the sales facility.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.58.1-58.1
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• 2010

In solar cell module manufacturing, single solar cells has to be joined electrically to strings. Copper stripes coated with tin-silver-copper alloy are joined on screen printed silver of solar cells which is called busbar. The bus bar collects the electrons generated in solar cell and it is connected to the next cell in the conventional module manufacturing by a metal stringer using conventional hot air or infrared lamp soldering systems. For thin solar cells, both soldering methods have disadvantages, which heats up the whole cell to high temperatures. Because of the different thermal expansion coefficient, mechanical stresses are induced in the solar cell. Recently, the trend of solar cell is toward thinner thickness below 180um and thus the risk of breakage of solar cells is increasing. This has led to the demand for new joining processes with high productivity and reduced error rates. In our project, we have developed a new method to solder solar cells with a laser heating source. The soldering process using diode laser with wavelength of 980nm was examined. The diode laser used has a maximum power of 60W and a scanner system is used to solder dimension of 6" solar cell and the beam travel speed is optimized. For clamping copper stripe to solar cell, zirconia(ZrO)coated iron pin-spring system is used to clamp both joining parts during a scanner system is traveled. The hot plate temperature that solar cell is positioned during lasersoldering process is optimized. Also, conventional solder joints after $180^{\circ}C$ peel tests are compared to the laser soldering methods. Microstructures in welded zone shows that the diffusion zone between solar cell and metal stripes is better formed than inIR soldering method. It is analyzed that the laser solder joints show no damages to the silicon wafer and no cracks beneath the contact. Peel strength between 4N and 5N are measured, with much shorter joining time than IR solder joints and it is shown that the use of laser soldering reduced the degree of bending of solar cell much less than IR soldering.

• Journal of Korean Society of Transportation
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• v.22 no.7 s.78
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• pp.41-48
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• 2004

We may consider the inducement of demand to public transportation as a solution to relieve traffic congestion and pollution. Subway has merits as moving on schedule, transporting more people than bus. But subway is required a vast investment in the early stage of construction has a huge debt. So it runs into red figures, and on this account, services of subway are falling more and more. Development of subway's operation cost function is useful to understand structure of subway's operation and catch the relations of operation cost and actual results. In addition, we can present the policy that is a helpful to the operation as development of operation cost function. But there are short of studies about operation cost deal with a subway comparison with local train. Because local train has many lines and data, on the other hand, subway has one to four lines and less data. Most of previous studies sought the operation cost function of Seoul. So this study aimed to develop and apply the operation cost function of Seoul, Incheon, Busan and Daegu area using full allocation method. In this study, we considered the number of passengers, track-km, train-km, revenue as actual results. By appling the operation cost function, we compared the average cost of each city and confirmed the existence of economies of scale about the number of passengers, train-km.

• Journal of Korean Society of Rural Planning
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• v.6 no.1 s.11
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• pp.19-28
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• 2000

Now in order to overcome the weakest points of the rural areas of the city of Kimje and, transform them into rural cultural villages which have local governing systems suitable to new localization age and activate this plan, we selected Daesan Village as a model village which had shown a lot of potentials in the basic research and studied it dividing it into the former part and the latter part. We studied Daesan village in the former part focusing on state analysis and basic ideas and in the latter part focusing on master plan and detail planning. We can summarize the conclusion like the followings. 1. Daesan Village located 8 kilometer away from the downtown Kimje and the city of Iksan respectably has comparatively good environment of good sunny place as an open field whose surrounding configuration of the ground consists of farming lands and low hills in front and rear. It has 38 farming households in all. 2. Human environment(인문환경); the village road whose width is about 4 meters is forming a flow system forking off into three. There is a route bus which operates three times a day even into the inside of the village. The main sources of revenue are vegetables in facilities, fruits and floriculture. Their average revenue is about 10.5 million won. 3. Here in DaeSan Village a legend dealing with Teasan literally meaning a big mountain consist of th village's tradition and you can see the tombs of a very faithful son and Anwi an army general in the age of the Japanese Invasion of Korea of 1592 to 1598 inside the village. 4. 85 out of the eitire population 141 whose age are over 20 showed very positive attitudes in a questionnaire about, making the village a cultural one and its development. 5. The basic of planned ideas is to increase the revenue of the farming household by making the village a professional farming one which has a state-of the-art production facility and agricultural technique. It is to make the village the one where people can enjoy the sense of the rural life and the farmer can enjoy their lives through consumptive and consistant leisure and resting activities. 6. We are planning to make entrance space, life space, rest and sport space, and cultural space considering the characteristics of the village and the demand of the resident. We are also planning to make tile entire city of Kimje an information transmitting base in short and long term perspectives. 7. DaeSan Village was planned as a place where tradition and the future exist together. On the basis of this concept we planned future programs for Daesan Village and in the latter part of the study master plans and detail plans will be continued.the regional agricultural condition. The development permissions were only during the period of restricted to use ($1979.12{\sim}1993.11$). We propose that the authority of development permission should be given to the local autonomy government, because the local government has the knowledge of its individual agricultural conditions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3499-3510
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• 2015

To cope with the increased demand on the intra-city transportation by urban rails, the introduction of the light rail transit (LRT) systems has been expedited in Korea due to the possible reduction of both the development and operation costs from adopting LRT systems. The LRT systems have so far been designed, constructed and operated based on the corresponding law and regulations. It has been conceived that fully complying with the existing guidelines may incur some extra costs on LRT. In addition, the present design of LRT stations seems to require unnecessarily long flow of passengers traffic, particularly for disabled people. In this paper, as an approach to solving the aforementioned issues, an introduction of 'LRT stops' has been studied where the stops are similar in concept to bus stops and are intended to replace the stations of a bigger scale in general. Specifically, necessary guidelines for design have been developed by modifying the existing ones to be fit with LRT stops. A design case was also presented to evaluate them. The effective use of the results reported here will provide an opportunity of cost reduction in connection with the construction and operation, and also let people benefit from convenient use of rails, thereby resulting in enhanced transportation welfare.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.5
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• pp.551-557
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• 2021

Attached parking lots installation criteria is determined by use, total floor area, etc. according to the Parking Lot Act and local government ordinances. However, with traffic demand increase inconvenience about use of culture and assembly facilities have been raised. When planning number of parking lots for cultural and assembly facilities, legal parking lots and unit parking lots are used, but this causes inconvenience and traffic problems on the surrounding roads, because reality and convenience are not considered. Therefore, this study intend to present an realistic number of parking lots calculating equation for movie theater in Gwangju Metropolitan City. After investigating number of parking lots, number of screens, number of seats, total floor area, bus route and illegal parking for a cultural facility in Gwangju Metropolitan City, prediction model for calculating number of parking lots was presented using SPSS regression analysis. As a result of comparing prediction model and unit method, the prediction model was be closer actual cumulative parking space, so prediction model verification was completed. Based on the model verified in this study, Realistic number of parking lots will be installed. However, due to limitations of research on specific areas, research on various facilities should continue in consideration of regional, population, and urban characteristics