• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.4
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• pp.259-267
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• 2018

The subset-sum problem is to find out whether or not the element sum of a subset within a finite set of numbers is equal to a given value. The problem is a well-known NP-complete problem, which is difficult to solve within a polynomial time. Genetic algorithm is a method for finding the optimal solution of a given problem through operations such as selection, crossover, and mutation. Dynamic programming is a method of solving a given problem from one or several subproblems. In this paper, we design and implement a genetic algorithm that solves the subset-sum problem, and experimentally compared the time performance to find the answer with the case of dynamic programming method. We selected a total of 17 test cases considering the difficulty in a set with 63 elements of positive number, and compared the performance of the two algorithms. The presented genetic algorithms showed time performance improved by 84% on 13 of 17 problems when compared with dynamic programming.

• Progress in Medical Physics
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• v.13 no.2
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• pp.104-108
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• 2002

As intensity modulated radiation therapy compared with conventional radiation therapy, tumor target dose increased and normal tissues and critical organs dose reduced. In brain tumor, treatment planning of intensity modulated radiation therapy was practiced in 4MV, 6MV, 15MV X-ray energy. In these X-ray energy, was considered the dose distribution and dose volume histogram. As 4MV X-ray compared with 6MV and 15MV, maximum dose of right optic-nerve increased 10.1％, 8.4％. Right eye increased 5.2％, 2.7％. And left optic-nerve, left eye, optic chiasm and brainstem increased 1.7％ - 5.2％. Even though maximum dose of PTV and these critical organs show different from 1.7％ - 10.1％ according to X-ray energies, these are a piont dose. Therefore in brain tumor, treatment planning of intensity modulated radiation therapy in 9 treatment field showed no relation with energy dependency.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.6
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• pp.92-101
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• 2023

The increasing use of personal mobility has led to a rise in traffic accidents and social issues. Consequently, the government is continually revising laws and regulations to address the problems associated with personal mobility. This study conducted a survey that reflects user characteristics and public perceptions based on the law revised in May 2021. The personal characteristics, legal awareness, usage patterns, risk characteristics, and risk factors were analyzed. The analysis indicated that driving on roads without separate sidewalks, speeding, and carrying passengers are hazardous practices. Moreover, Poor awareness of the legal framework governing personal mobility results in law violations. These results are significant as they highlight the need for policy measures regarding institutional and legal improvements, and they underscore the importance of enhancing social awareness about safety as personal mobility become more widespread.

• The Journal of Society for e-Business Studies
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• v.18 no.4
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• pp.145-167
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• 2013

This paper proposes a method to compare planned processes with actual processes of bock assembly operations in shipbuilding industry. Process models can be discovered using the process mining techniques both for planned and actual log data. The comparison between planned and actual process is focused in this paper. The analysis procedure consists of five steps : 1) data pre-processing, 2) definition of analysis level, 3) clustering of assembly bocks, 4) discovery of process model per cluster, and 5) comparison between planned and actual processes per cluster. In step 5, it is proposed to compare those processes by the several perspectives such as process model, task, process instance and fitness. For each perspective, we also defined comparison factors. Especially, in the fitness perspective, cross fitness is proposed and analyzed by the quantity of fitness between the discovered process model by own data and the other data(for example, the fitness of planned model to actual data, and the fitness of actual model to planned data). The effectiveness of the proposed methods was verified in a case study using planned data of block assembly planning system (BAPS) and actual data generated from block assembly monitoring system (BAMS) of a top ranked shipbuilding company in Korea.

• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.99-110
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• 2008

It is commonly estimated that there is a much higher potential for accidents at a crossroads than along a single road due to its plethora of conflicting points. According to the 2006 figures by the National Police Agency, the number of traffic accidents at crossroads is greatly increasing compared to that along single roads. Among others, crossroads installed with traffic signals have more varied influential factors for traffic accidents and leave much more room for improvement than ones without traffic signals; thus, it is expected that a noticeable effect could be achieved in safety if proper counter-measures against the hazards at a crossroads were taken together with an estimate of causes for accidents This research managed to develop models for accident forecasts and accident intensity by applying data on accident history and site inspection of crossroads, targeting four selected downtown crossroads installed with traffic signals. The research was done by roughly dividing the process into four stages: first, analyze the accident model examined before; second, select variables affecting traffic accidents; third, develop a model for traffic accident forecasting by using a statistics-based methodology; and fourth, carry out the verification process of the models.

• KIPS Transactions on Software and Data Engineering
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• v.9 no.7
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• pp.221-228
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• 2020

Part-of-Speech (POS) tagged corpus is a collection of electronic text in which each word is annotated with a tag as the corresponding POS and is widely used for various training data for natural language processing. The training data generally assumes that there are no errors, but in reality they include various types of errors, which cause performance degradation of systems trained using the data. To alleviate this problem, we propose a novel method for detecting errors in the existing POS tagged corpus using the classifier of XGBoost and cross-validation as evaluation techniques. We first train a classifier of a POS tagger using the POS-tagged corpus with some errors and then detect errors from the POS-tagged corpus using cross-validation, but the classifier cannot detect errors because there is no training data for detecting POS tagged errors. We thus detect errors by comparing the outputs (probabilities of POS) of the classifier, adjusting hyperparameters. The hyperparameters is estimated by a small scale error-tagged corpus, in which text is sampled from a POS-tagged corpus and which is marked up POS errors by experts. In this paper, we use recall and precision as evaluation metrics which are widely used in information retrieval. We have shown that the proposed method is valid by comparing two distributions of the sample (the error-tagged corpus) and the population (the POS-tagged corpus) because all detected errors cannot be checked. In the near future, we will apply the proposed method to a dependency tree-tagged corpus and a semantic role tagged corpus.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4D
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• pp.469-476
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• 2008

Recently, TOD gains popularity as a traffic solution measure of high density urban regeneration projects. The purpose of this study is to investigate traffic impacts of high density TOD projects, and to identify the issues to be resolved. For a case study, it chooses Gangnamgucheong station in Gangnam area served by two subway lines, and designates 400m radius from the station as a site for high-density development. The MOEs chosen for this study is traffic volume, time, distance, speed, and mode share. The SECOM model is adopted for traffic simulation. The analysis results show that high-density TOD is an effective tool for traffic improvement even with only one station area being implemented. It is found that the traffic volume increases near the station in nature where high-density development occurs, but it declines overall in the rest of Gangam area. The total travel time and distance of passenger vehicles decline, meaning that the traffic condition becomes better than before. With regulation on parking supply, the improvement becomes more vivid. In terms of the changes of traffic speed, both alternatives show 4.1% increase in speed, but the difference between alternatives is not quite noticeable because of the induced vehicle demand driven to the streets with improved traffic condition. The mode share changes occur for the benefit of subway ridership, because the study station is equipped with two subway line services. When mixed with parking supply restriction, the impact becomes clearer.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4D
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• pp.505-512
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• 2008

Over the past years, complex project which has the object to accomplish housing complex, commercial complex etc, recently is changing to multi-complex projects because of development in IT sector. Improvement in the quality of life, life pattern has been and is being changed, these modernized and improved version of life brings the concept of U-city. Department of urban planning and engineering, civil engineering and architecture engineering in every university educate students according to the changing world in order to handle these complex projects in real world. In most cases department of urban planning and engineering teach project planning and department of civil and architecture engineering teach project design and construction. In most of the projects planning followed by design and construction need to be accomplished, but current observation in the present curriculum shows that it is difficult to expect the continuity. The present curriculum of civil engineering has to change as complex projects deal with various different structures during the design and construction phase of these projects. This study examined curriculums from the department of urban and civil engineering related to structural design and construction and survey importance of design works which overlap urban and civil engineering targeted on design engineers. After understanding design works and results obtained from survey we propose for an advanced efficiency method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.763-772
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• 2019

Recently, there is a great expectation for the sustainable effect of TOD and apply it to urban planning and design. However, there are few research on the quantitative evaluation method of the effect. The purpose of this study is to propose a quantitative way to assess the effectiveness of TOD(Transit Oriented Development)'s vehicle traffic reduction in the urban planning phase, based on the land-use plan. Firstly, it proposes a method to convert the information contained in the land-use plan into a network and secondly a method to estimate the travel distance based on the network. In the first phase, the roads in the land-use plan are converted into links and the intersection of the roads into nodes. The area and the height of the zones included in the land-use plan are converted into the weights on adjacent nodes. The second phase assumes the frequency at which travel occurs between nodes on the network is relative to the weights and estimates the travel distance by dividing it into a pedestrian and a vehicle. Then, taking the city without TOD as the object, through comparison present city and alternatively redesigned city to the analysis of TOD effect. In this study, the application of these methods to Bundang as of 1997 and alternatively redesigned Bundang showed that about 39.94 percent of the vehicle traffic reduction effects occurred. Furthermore, the pedestrian traffic ratio of alternatively redesigned Bundang increased to 2.39%.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.08a
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• pp.281-286
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• 1998

ETRI에서 개발 중인 대화체 음성언어번역 시스템에 대하여 기술한다. 현재, ETRI는 DAM성언어번역 국제 공동 연구콘서시움인 C-STAR에 핵심참가기관으로 참여하여, 한일, 한영음성언어번역 시스템을 개발하고 있으며 1999년 국제 공동시험을 계획하고 이？. 최근의 연구 진행상황을 간추리면, 먼저 음성인식분야에서 유무성음 및 묵음정보를 미리 추출하여 이를 탐색에 활용하였으며, 음향모델 규모의 설정을 위한 교차 엔트로피 기반 변이음 군집화 알고리즘이 구현되었다. 또한 대상어휘의 확장을 위하여 의사형태소의 개념을 도입하였다. 언어번역분야에서는 이전과 같은 개념기반의 번역을 시도하고 있으며, C-STAR 회원기관과 공동으로 중간언어 규격을 정의하고 있다. 음성합성분야에서는 훈련형 합성기를 개발하여 합성데이타베이스 구축기간을 현저하게 줄였다.