• Journal of Environmental Science International
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• v.14 no.11
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• pp.1005-1014
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• 2005

The purpose of this research was to present multi-criteria which were related to the heat island and find methods which decreased heat island affection on the ecological landscape planning. The results of this study were as follows. According to the analysis of surface temperatures, the first grade was the outside-city like a mountain and its temperature was less than $13.0^{\circ}C$. The fifth grade was the downtown, industrial area and its temperature was more than $26.9^{\circ}C$. Therefore, the result was seen the serious heat-island effect. The results of field survey, the closer to the first grade, the higher the value of green coverage. The closer to the fifth grade, the higher the value of impermeability surface, paving materials and colors. According to the correlation analysis, the temperature had high correlation with impermeability surface, paving materials and colors. According to the simple regression analysis, permeability surface, green coverage, topography, impermeability surface, paving materials f: colors, human impact related with surface temperatures. To plan for the decrease of Heat-Island Effect needed the extension of green space, decrease of impermeability surface. This research suggested data for urban green plan and decrease of heat island effect, but there was a limit to get the objective method for grade classification because of lacking in the basic data, the research of multi-criteria will be accomplished continuously.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.4
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• pp.223-230
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• 2014

In this paper, the wind-induced response characteristics of freeform shaped tall building is studied by using FSI analysis. The analytical models are twist shaped ones at representing type of atypical tall building, and this study focused on the relationship between twist angle and wind acceleration. Firstly, 1-way FSI analysis is performed, so maximum lateral displacement of the analytical model for 100 years return period wind speed is calculated, then the elastic modulus of a structure that satisfies the constraints condition is evaluated. And 2-way FSI analysis is carried out. so acceleration of the analytical model for the evaluated modulus of elasticity and arbitrary density is predicted through time history analysis. The basic model is a set of a square shape, height is 400m, slenderness ratio is 8, and twist model is rotated at square model from 0 to 90 degrees at intervals of 15 degrees and from 90 to 360 degrees at intervals of 90 degrees. According to the result of predicting wind acceleration by the shape of each model, the wind vibration effect of square shape model is confirmed to be sensitive more than a twist shape ones.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.11
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• pp.921-933
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• 2018

There is a method to enhance the pure navigation performance of INS(Inertial Navigation System) through the rotation of inertial measurement unit to compensate error sources of inertial sensors each other and that INS using this principle of operation is called rotational INS. In this paper, the exact error analysis of rotational INS based on ring laser gyro considering the coupling effect with gravity and earth rate is performed to evaluate the navigation performance by inertial sensor error sources. And error analysis and performance evaluation result confirmed by modelling and simulation is also proposed in this paper.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.3
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• pp.9-15
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• 2019

Large global online shopping malls, such as Amazon, offer services in English or in the language of a country when their products are sold. Since many customers purchase products based on the product reviews, the shopping malls actively utilize the sentimental analysis technique in judging preference of each product using the large amount of review data that the customer has written. And the result of such analysis can be used for the marketing to look the potential shoppers. However, it is difficult to apply this English-based semantic analysis system to different languages used around the world. In this study, more than 500,000 data from Amazon fine food reviews was used for training a deep learning based system. First, sentiment analysis evaluation experiments were carried out with three models of English test data. Secondly, the same data was translated into seven languages (Korean, Japanese, Chinese, Vietnamese, French, German and English) and then the similar experiments were done. The result suggests that although the accuracy of the sentimental analysis was 2.77% lower than the average of the seven countries (91.59%) compared to the English (94.35%), it is believed that the results of the experiment can be used for practical applications.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.2
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• pp.136-155
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• 2014

The purpose of this study is to analyze the thermal comfort in Yeongnam area using climatic data and GIS data in order to determine regions necessary to improve thermal environment policies. The results of the calculated PET show that Daegu city is high and Bonghwa-gun is low compared to other regions. PET was compared with the typical classification according to regional characteristics. As a result, PET value of rural areas such as Changnyeong-gun, Haman-gun and Goryeong-gun was high but Green space was too low compared to other rural areas. Yeongnam area was classified according to the value of PET using cluster analysis. As a result, more low grade areas show that green space ratio was low and facility area was high. It is determined that there is a relationship between thermal comfort and land cover. The thermal comfort evaluation map in Yeongnam area will be useful for urban planning in order to establish a sustainable city in climate change.

• The Journal of Korean Association of Computer Education
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• v.23 no.3
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• pp.49-58
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• 2020

Organizing entrance evaluation system for selecting students who can become expert in data science field according to need of the age and social demand is important. This study was conducted for the purpose of analyzing data science field graduate school entrance evaluation system and deriving implications after taking into account the importance of talents possessing convergence competency. For this aim, a total of 22 graduate schools in 7 countries have been selected targeting data scientist postgraduate program around the world. The selected graduate schools have been analyzed based on qualifications, necessary skills prior to entrance, entrance conditions, and selection methods. As a result of the analysis, 'graduate school which I can apply for regardless of possessing undergraduate degree or undergraduate major (63.6 percent)' in qualifications category, 'graduate school which mentioned skills required in completing master's degree prior to entrance (63.6 percent)' in skills required prior to entrance category, 'graduate school which does not mention separate entrance condition (81.8 percent)' in entrance conditions category, and 'graduate school selecting students merely based on document screening (68.2 percent)' in selection methods category took the highest portion. Based on the above, this study summarized the results of the data scientist process and suggested implications for objectifying admission evaluation.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.4
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• pp.23-32
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• 2023

The seismic performance of buried PE pipes is reported to be favorable due to their exceptional elongation capacity at break. Although a seismic performance evaluation procedure based on the response displacement method has been summarized in Korea for fusion-bonded PE pipes, there is currently no procedure available for mechanically jointed PE pipes. This article aims to present a seismic performance evaluation procedure based on the response displacement method specifically designed for mechanically jointed PE pipes in Korea. When employing the mechanical joining method for PE pipes, it is recommended to adhere to the evaluation procedure established for segment-type pipes. This involves assessing the stress induced by the pipe, the expansion and contraction strain of the joint, and the bending angle of the pipe joint. Furthermore, the coefficient of inhomogeneity of the soil, which is necessary for estimating the axial strain of the ground, is introduced. Additionally, a computation method for determining lateral displacement and reconsolidation settlement in soil susceptible to liquefaction is proposed. As a result of the sensitivity analysis considering the typical soil condition in Korea, the mechanically jointed PE pipe with a certain quality was shown to have good structural seismic safety when soil liquefaction was not considered. This procedure serves as a valuable tool for seismic design and evaluating the seismic performance of mechanically joined buried PE pipes, which are primarily utilized for connecting small-diameter pipes.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.6
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• pp.675-683
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• 2011

When impacts by falling objects are applied to the structures, vertical resisting member(column or column group) results in progressive collapse. By knowing clearly load-deformation relationship of a structural frame, to prevent progressive collapse by absorbing potential energy of falling objects though column groups are lost by the impact of falling object accidently. If residual strength in vertical direction exceeds vertical load, which the sum of the weight of falling objects and usual supportive vertical load as the result of absorbing released location energy, it does not result in progressive collapse. On the other hand, in case when weight of falling objects is included in usual supportive vertical load. In this paper, 1-story 4-spans model is analyzed by non-linear FEM and to examine the level of deterioration, limit analysis of 1-story 4-spans plane frame was carried out.

• Journal of the Korea Convergence Society
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• v.11 no.6
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• pp.1-6
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• 2020

In this study, research on character recognition, which is one of the fields of computer vision, was conducted. Optical character recognition, which is one of the most widely used character recognition techniques, suffers from decreasing recognition rate if the recognition target deviates from a certain standard and format. Hence, this study aimed to address this limitation by applying deep learning techniques to character recognition. In addition, as most character recognition studies have been limited to English or number recognition, the recognition range has been expanded through additional data training on Korean text. As a result, this study derived a deep learning-based character recognition algorithm for Korean text recognition. The algorithm obtained a score of 0.841 on the 1-NED evaluation method, which is a similar result to that of English recognition. Further, based on the analysis of the results, major issues with Korean text recognition and possible future study tasks are introduced.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.1
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• pp.1-21
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• 2020

The domestic abandoned mines are generating subsidence and it is difficult to predict this subsidence and evaluate the risk. The study of the subsidence risk evaluation using the existing numerical analysis only applies the integrative property to the geological structure and ground condition, and analyzes the goaf peripheral plastic domain. Also, there is a realistic limit that only restricted materials can be apprehended in securing the input information, which leads to the low reliability of the numerical analysis result. In this study, 2-dimensional modeling was performed by applying the field geological structure and ground information targeting abandoned mine where the subsidence occurred. Also, the analysis model was revised by repeating the numerical analysis for the difference between the real subsidence ground information and the analysis result to be minimized by modifying the ground property. This revision was automated by applying the optimization technique and the gradational optimal design method dividing multiple ground properties was developed.