• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.1
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• pp.75-82
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• 2011

The numerical analysis of the reduction of reaction mechanism for the ignition of dimethyl ether (DME) was performed. On the basis of a detailed reaction mechanism involving 79 species and 351 reactions, the peak molar concentration and sensitivity analysis were conducted in a homogeneous reactor model. The reduced reaction mechanism involving 44 species and 166 reactions at the threshold value $7.5{\times}10^{-5}$ of the molar peak concentration was established by comparing the ignition delays the reduced mechanism with those the detailed mechanism. The predicted results of the reduced mechanism applied to the single-zone homogeneous charge compression ignition (HCCI) engine model were in agreement with those of the detailed mechanism. Therefore, this reduced mechanism can be used to accurately simulate the ignition and combustion process of compression ignition engine using DME fuel.

• Tunnel and Underground Space
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• v.18 no.6
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• pp.393-407
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• 2008

To protection of fire accident and to minimize danger of spreading the disaster. in railway tunnel, MCT (the Ministry of Construction and Transportation) published "Rules about the Safety Standard of Railroad (2005.10.27)" and "The Detailed Safety Standard of Railroad (2006.9.22)". QRA(Quantitative Risk Analysis) results are applied to establish the fire protection facilities in railway tunnel so that institute the reasonable application about the fire safety facilities However, it is difficult to perform the fire safety design due to lack of the detailed standards about event scenario, fire intensity, incidence rate of accidents etc. Therefore, This paper introduces the practical method about detailed standards of QRA.

• Journal of Environmental Impact Assessment
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• v.10 no.2
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• pp.147-155
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• 2001

Vegetation maps present an inventory of existing plant communities, their location, extent and geographical distribution in the area concerned. For green space management and environment assessment accurate vegetation maps can be used effectively for analyzing the relationships between vegetation and the physical environment. However, the Current Vegetation Map, Forest Stand Map, and Green Naturality Map in Korea do not represent the status of vegetation community exactly. Therefore, the purpose of this study is to produce a detailed vegetation map at urban neighborhood parks in Korea by collecting the exact current vegetation data from field survey, and remote sensing(RS) and storing these data in geographical information systems(GIS). Ultimately it is intended to be used in planning and managing the urban green space. The study area is 66.1ha and it is classified into total 19 communities together with parks, orchards, bare land, grassland, tombs and gardens, etc. There is 53.7ha(81.2%) difference between the detailed vegetation map and the current vegetation map. There is also 46.9ha(70.8%) difference between the detailed vegetation map and forest stand map. After this study, it was concluded that it needs producing the detailed vegetation map used in managing urban green spaces because the existing vegetation map does not represent the status of vegetation in the study site.

• KIEAE Journal
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• v.17 no.4
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• pp.49-57
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• 2017

Purpose: Design inducement incentive item and formula on permitted floor area ratio in district detailed plan have been improved to reflect the actual application of guidelines and the social needs of city and architecture. However, the current guideline has a limit to realize the purpose of the plan. This study proposes improvement of the items and parameters in formula. Method: This study analyzed the district detailed planning guidelines since 2000 and the cases of general type district unit plan. In order to propose improved items and parameters, planing purposes and present parameters were compared and analyzed. Result: Items of guidelines have been changed according to public needs. High necessity items were applied to large parameters, and these items have been changed as the guideline changes. Diversity of items depended on regional characteristics, and parameters were more flexible than items for most cases. The purposes of plans, parameters and items were analyzed and it revealed four items needed improvement; the inducement of the limited building line, the improvement of the pedestrian and street environment, the necessity of the open space, and strengthening of the regional agreement. For improvement, this study added items and improved the relevance between items and sub-items. The parameters were improved by considering the importance, feasibility and comparing them with each other. Simulated result confirmed that proposed guideline is appropriate to operate, and also characteristics of area encourage to operate it more flexible.

• Journal of architectural history
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• v.28 no.6
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• pp.19-30
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• 2019

This study explores the application aspect of The detailed rules of Census (1896) through the change of Kan numbers in Gyeonpyeong-bang. Although Gyeonpyeong-bang was a high-priority area because of its location, it was difficult to trace the operation of the urban situation due to lack of data. This study is focusing on restoring space and society in the Gyeonpyeong-bang using the information on the type of houses and the number of Kan listed in the family register of Hanseong-bu. The detailed rules of Census sets out provisions for the family registry and the rules of making Tong. Especially when it comes to the rules of making Tong, this rule deals with the code of making ten Hos into one Tong. This study was conducted by dividing the status of the Tong into three types: uncompleted Tong, exceeded Tong without vacant Ho number, and exceeded Tong with the vacant Ho number. Since these three types of Tong are in the process of change towards the complete Tong with 10 Hos, they were thought to be able to demonstrate the specific application of the rules. This study will be meaningful as a case study that expands the point of existing research on the Tong making rules, which was not focused relatively on restoring urban conditions at that time, by looking at the changes in exceptions that deviated from the Sipgajaktong rule.

• The KIPS Transactions:PartC
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• v.11C no.5
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• pp.659-670
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• 2004

Handoff is one of the most important features for the user's mobility in a wireless cellular communication system. It is related to resource reservation at nearby cells. Resource reservation to the new connection point should occur prior to handoff to enable the user to receive the data or services at the new location, at the same level of service as at the previous location. For the efficient resource reservation, mobility prediction has been reported as an effective means to decrease the call dropping probability and to shorten the handoff latency in a wireless cellular environment. A recently proposed algorithm, ZMHB, makes use of the history of the user's positions within the current cell to predict the next cell. But, the prediction of the ZMHB algorithm is found to be 80∼85% accurate for regular and random movements. In this paper, we propose a new improved ZMHB mobility prediction algorithm, which is called Detailed-ZMHB that uses detailed-zone-based tracking of mo-bile users to predict user movements. The effectiveness of the proposed algorithm is then demonstrated through a simulation.

• Journal of Korea Multimedia Society
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• v.9 no.10
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• pp.1282-1295
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• 2006

This paper proposes a method of image tile mosaics to preserve detailed depiction of the source image. This method enhance the shortcoming of the previous mosaic methods that cannot express the detailed depiction because of the gap between tiles. Our method is implemented by the usage of image tiles to preserve detailed depiction of the source image, as well as the usage of 2-layered tiles to.eliminate the gap between tiles. The method suggested in this paper are composed of following process. First of all, the position of the upper layer tile is located through a centroidal voronoi diagram to which an edge avoidance technique is applied, and the position of the lower layer tile is calculated using Delaunay triangulation. Secondly, discover the size and direction field of the tile considering the relation between tiles. Thirdly, adopt a photomosaic technique to use the image tiles. At this time, the technique of multi-level indexing is used to accelerate the speed of image searching. Through above process, the gap between tiles is minimized against other methods and a mosaic image with a maximized detailed description is achieved.

• Atmosphere
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• v.29 no.5
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• pp.567-583
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• 2019

In this study, the high-resolution numerical simulations considering detailed anthropogenic heat, albedo, emission and roughness length are analyzed by using single layer Urban Canopy Model (UCM) in Weather Research Forecast (WRF). For this, improved urban parameter data for Seoul Metropolitan Area (SMA) was collected from global data. And then the parameters were applied to WRF-UCM model after it was processed into 2-dimensional topographical data. The 6 experiments were simulated by using the model with each parameter and verified against observation from Automated Weather Station (AWS) and flux tower for the temperature and sensible heat flux. The data for sensible heat flux of flux towers on Jungnang and Bucheon, the temperature of AWS on Jungnang, Gangnam, Bucheon and Neonggok were used as verification data. In the case of summer, the improvement of simulation by using detailed anthropogenic heat was higher than the other experiments in sensible flux simulation. The results of winter case show improved in all simulations using each advanced parameters in temperature and sensible heat flux simulation. Improvement of urban parameters in this study are possible to reflect the heat characteristics of urban area. Especially, detailed application of anthropogenic heat contributed to the enhancement of predicted value for sensible heat flux and temperature.

• Journal of the Ergonomics Society of Korea
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• v.28 no.3
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• pp.103-114
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• 2009

This study investigated perceived discomfort and reasons related to use three information technology products (personal computer, mobile phone and digital television remote controller), and extracted the universal design factors. 240 people (30 females and 30 males for four age groups) participated in the one-to-one interview type of questionnaire, and replied to degree of discomfort at level of items and the reasons of discomfort at level of detailed elements for each product. As a result, almost all age groups answered that using input buttons of mobile phone and remote controller and watching display of mobile phone caused discomfort. Binary logistic regression of the detailed elements showed that response rate of discomfort mostly increased with age, except for specific elements such as shape of mouse and remote controller, and location of function button of mobile phone. Some of the detailed elements had high response rate of discomfort from all age groups. The age groups also showed similar tendency for the elements to select one alternative for the reason of discomfort, but not for sound volume and size of mobile phone and button sensitivity of remote controller. Finally, the universal design factors were extracted for each product based on the results, and divided into common factors and factors classified by the age group. Through this study, we identified using practices of various age groups and their demands for the products. It is expected that extracted detailed elements can be considered as important design factors to design the products universally.

• Journal of Korean Society of Archives and Records Management
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• v.18 no.3
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• pp.97-123
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• 2018

The purpose of this study is to analyze the difference between job importance awareness and actual job achievement of archivists of private universities through importance-performance analysis (IPA), and to analyze the difference between certified and noncertified archivists about the above two factors. To achieve the purpose, the detailed job activities were drawn through a review of laws, regulations, and policies. The detailed list of job activities was confirmed by a few current archivists, Using the confirmed list of detailed job activities, a survey was conducted for archivists of private universities. The collected data in the survey were analyzed using the IPA method. According to the study results, the two groups of archivists have a clear understanding of their jobs; however, environmental factors influence the actual achievement of the jobs.