• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.559-562
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• 2003

In this paper, we introduce a new method detecting thyristor faults of the power converter module in Control Rod Control System. When we control the currents in each coil of Control Rod Drive Mechanism by using the current control method, the current value can follow the current reference despite the faults like the missing phase or the diode acting. Comparing the fault current values with the normal current values, the bad transient characteristics of the abnormal current can make the operations of control rods incorrect. In this case, the information from the current trends cannot be enough to detect the fault occurrence in thyristors. Instead of the coil currents, the state of thyristors can be watched by measuring the coil voltages. In the existing system of Westinghouse type, the ripple detector takes charge of this task. But this detector has some shortcomings in the point of time for fault detection, we come to devise a new fault detection method solving the problems which belong to the ripple detector.

• Journal of Information Technology Services
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• v.21 no.3
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• pp.63-72
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• 2022

The extinction crisis of local cities, caused by a population density increase phenomenon in capital regions, directly causes the increase of vacant houses in local cities. According to population and housing census, Gunsan-si has continuously shown increasing trend of vacant houses during 2015 to 2019. In particular, since Gunsan-si is the city which suffers from doughnut effect and industrial decline, problems regrading to vacant house seems to exacerbate. This study aims to provide a foundation of a system which can predict and deal with the building that has high risk of becoming vacant house through implementing a data driven vacant house prediction machine learning model. Methodologically, this study analyzes three types of machine learning model by differing the data components. First model is trained based on building register, individual declared land value, house price and socioeconomic data and second model is trained with the same data as first model but with additional POI(Point of Interest) data. Finally, third model is trained with same data as the second model but with excluding water usage and electricity usage data. As a result, second model shows the best performance based on F1-score. Random Forest, Gradient Boosting Machine, XGBoost and LightGBM which are tree ensemble series, show the best performance as a whole. Additionally, the complexity of the model can be reduced through eliminating independent variables that have correlation coefficient between the variables and vacant house status lower than the 0.1 based on absolute value. Finally, this study suggests XGBoost and LightGBM based machine learning model, which can handle missing values, as final vacant house prediction model.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9933-9937
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• 2014

Background: Colorectal cancer is the third most common type of cancer in males and the second in females in Iran. Males are more likely to develop CRC than women and age is considered as a main risk factor for colorectal cancer. Prevalence of colorectal cancer has been increasing in Asian countries. Aim: The object of this study was to determine the clinical and pathology characteristics of colorectal polyps in Iranian patients and to investigate the variation between our populations with other populations. Materials and Methods: A total of 167 patients with colorectal polyps were included in our study. All underwent colonoscopy during 2009-2013 and specimens were taken through polypectomy and transferred to pathology. All data in patient files including pathology reports were collected and analyzed by SPSS 16 software. A two-tailed test was used and a P-value of < 0.05 was considered significant. Results: Mean age of participants was $57{\pm}15$. Some 84 were females (50.3%) and 83 males (49.7%). Total of 225 polyps were detected which 119 (52.9%) were in males and 106 (47.1%) were in females. Solitary polyps were observed in 124 patients (74%), 26 (15.6%) had two polyps and 17 (10.1%) with more than two polyps (three to five). Rectosigmoid was the site of most of the polyps (63.1%), followed by 19.6% in the descending colon, 7.6% in the transverse, 5.8% in the ascending, and 3.1% in the cecum, data being missing in two cases. Conclusions: Recto sigmoid was site of most of the polyps. The most prevalent type of lesion was adenomatous polyps detected in 78 (34.7%). Mixed hyperplastic adenomatous type observed in 70 (31.1%). This high prevalence of adenomatous polyps in Iranian patients implies the urgent need for screening plans to prevent further healthcare problems with colorectal cancer in the Iranian population.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.383-388
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• 2005

Depth recovery in robot vision is an essential problem to infer the three dimensional geometry of scenes from a sequence of the two dimensional images. In the past, many studies have been proposed for the depth estimation such as stereopsis, motion parallax and blurring phenomena. Among cues for depth estimation, depth from lens translation is based on shape from motion by using feature points. This approach is derived from the correspondence of feature points detected in images and performs the depth estimation that uses information on the motion of feature points. The approaches using motion vectors suffer from the occlusion or missing part problem, and the image blur is ignored in the feature point detection. This paper presents a novel approach to the defocus technique based depth from lens translation using sequential SVD factorization. Solving such the problems requires modeling of mutual relationship between the light and optics until reaching the image plane. For this mutuality, we first discuss the optical properties of a camera system, because the image blur varies according to camera parameter settings. The camera system accounts for the camera model integrating a thin lens based camera model to explain the light and optical properties and a perspective projection camera model to explain the depth from lens translation. Then, depth from lens translation is proposed to use the feature points detected in edges of the image blur. The feature points contain the depth information derived from an amount of blur of width. The shape and motion can be estimated from the motion of feature points. This method uses the sequential SVD factorization to represent the orthogonal matrices that are singular value decomposition. Some experiments have been performed with a sequence of real and synthetic images comparing the presented method with the depth from lens translation. Experimental results have demonstrated the validity and shown the applicability of the proposed method to the depth estimation.

• Culinary science and hospitality research
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• v.19 no.2
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• pp.149-166
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• 2013

The purpose of this study is to investigate what influence the external variables of the RFID system for eco-friendly agricultural products such as reliability, safety, effectiveness and innovation have on ease and usefulness, perceived value and behavioral intention. An empirical analysis were conducted to the general consumers over the age of 20 years who live in Seoul and Gyeonggi areas having experience of buying eco-friendly agricultural products in department stores, supermarkets and eco-friendly agricultural product specialty stores from November 10 to November 23, 2012, A total of 350 copies of questionnaire were distributed for this research and, excluding partial ones that were too concentrated on one side or found missing values, a total of 305 copies(87.1%) were used as the final statistical analysis data. The result shows that such external variables of the RFID system for eco-friendly agricultural products as liability, safety, effectiveness and innovation are useful enough as a theoretical basis for later study on RFID systems for eco-friendly agricultural products. Also, it reveals that, since all the process from production to sale of agricultural products can be seen, the products are provided safely for consumers, are objectively and rapidly investigated when problems occur, induce a positive attitude with their historical information, and are supplied through systematic management such as consumers' rights to know and choose and recall of unfit products.

• Journal of Arbitration Studies
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• v.21 no.3
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• pp.89-114
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• 2011

Environmental disputes not only possess the special characteristics of collectivity and plural value relativity but it also possesses the unique features of difficulty to prove cause and effect as well as the structural maldistribution of evidence and information. Therefore, the positive resolution of an environmental dispute can be brought about more easily with the Alternative Dispute Resolution (ADR) which can take the form of talks, compromises, as well as arbitration or mediation rather than through a trial process. Such being the case, this paper first looks into the problems and effectiveness of the arbitration system of environmental lawsuits and then takes an even closer look at Korea's environmental dispute arbitration system and finally offer some reform methods. In Korea, the environmental dispute arbitration system was implemented in 1991 and has been executed since then. Although this system does have positive features such as the high rate of coming to an agreement between the involved parties but unfortunately, most of the cases rely on decisions based on right and wrong which cannot but be far away from the intentions of the ADR system. It is heavily centered around claims regarding psychological compensation regarding noise and vibrations and the ratio of the actual amount of compensation is comparatively lower than the requested amount. In addition, with the limits in organization and manpower, it leads to a lack of professionalism as well as the problem of low usage with the low awareness rate. As reform measures against the aforementioned problems, this paper suggests the following. First, in order to activate the arbitration process more fully, it proposes aggressive usage of compulsory arbitration as well as submission to arbitration, while at the same time raising ADR professionals to fill in the missing gaps. Secondly, in order to overcome the problem of concentration of related cases, making representative lawsuits of environmental organizations would be a good idea. It also states that in order to make the compensation amount more realistic, it should go out of the across-the-board decision making process and reach a decision about the compensation amount that takes the individual situation's dispute into consideration. In order to boost the professionalism of the environmental dispute arbitration, it is necessary to reform the organization and manpower such as expanding the number of members of full standing, and increasing the professionalism of the examiners. Also, to increase the usage rate of the ADR system, the paper suggests stationing a civilian consultant regarding environment, or activating the compulsory arbitration which is the premise for public participation on the part of the residents.

• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.179-188
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• 2021

Biodiversity informatics applies information technology methods in organizing, accessing, visualizing, and analyzing primary biodiversity data and quantitative data management through the scientific names of accepted names and synonyms. We reviewed the GBIF data published by China, Japan, Taiwan, and internal institutes, such as NIBR, NIE, and KNA of the Republic of Korea, and assessed data in diverse aspects of data quality using BRAHMS software. Most data from four Asian countries have quality problems with the lack of data consistency and missing information on georeferenced data, collectors, collection date, and place names (gazetteers) or other invalid data forms. The major problem is that biodiversity management institutions in East Asia are using unstructured databases and simple spreadsheet-type data. Owing to the nature of the biodiversity information, if data relationships are not structured, it would be impossible to secure the data integrity of scientific names, human names, geographical names, literature, and ecological information. For data quality, it is essential to build data integrity for database management and training systems for taxonomists who are continuous data managers to correct errors. Thus, publishers in East Asia play an essential role not only in using specialized software to manage biodiversity data but also in developing structured databases and ensuring their integration and value within biodiversity publishing platforms.