• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.253-256
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• 2009

This paper describes a core generator (FFT_Core_Gen) which generates Verilog HDL models of 8 different FFT/IFFT cores with $N=64{\times}2^k$($0{\leq}k{\leq}7$ for OFDM-based communication systems. The generated FFT/IFFT cores are based on in-place single memory architecture, and use a hybrid structure of radix-4 and radix-2 DIF algorithm to accommodate various FFT lengths. To achieve both memory reduction and the improved SQNR, a conditional scaling technique is adopted, which conditionally scales the intermediate results of each computational stage, and the internal data and twiddle factor has 14 bits. The generated FFT/IFFT cores have the SQNR of 58-dB for N=8,192 and 63-dB for N=64. The cores synthesized with a $0.35-{\mu}m$ CMOS standard cell library can operate with 75-MHz@3.3-V, and a 8,192-point FFT can be computed in $762.7-{\mu}s$, thus the cores satisfy the specifications of wireless LAN, DMB, and DVB systems.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.271-276
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• 2009

An local area weather condition monitoring system to minimize many disasters from the sudden change of weather condition in local and mountain area is proposed. Firstly, the comparison of present state of the related monitoring systems and the possibility of realization with some merits are investigated. Moreover, this paper present direction of local area weather condition monitoring system based on integration of wireless sensor network and CDMA network following some case study. Through the efficient integration of both networks, the measured weather condition data from sensors can be transmitted to the server or mobile to monitor with high reliability. The proposed monitoring system will guide new type of project in wireless sensor network and support alarm service of the sudden change of weather condition to mobile user from central official regulations.

• Journal of Korea Port Economic Association
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• v.30 no.1
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• pp.119-142
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• 2014

This study aims to evaluate the factors which affect the competitiveness of Gwangyang port, and to suggest strategies for the enhancement of its competitiveness by priority. This study inquires both 5 key rating factors: port location, port operations management, port costs, port facilities, and hinterland conditions and the priority of 14 detailed assessments through AHP method. First, the importances of main evaluation items for port competitiveness are analysed in the following orders: port location, port facilities, port costs, port operations, hinterland conditions. Second, the comprehensive importances based on the detailed evaluation properties complex weighting are identified in the following orders: connectivity with hinterland, accessibility of international harbor, incentives, the area of terminal, expertise and skills of port operations personnel, container throughput, and scale berths. Third, the strategies referring to the port location like centrality, transit, and merit on use should be actively conducted for the promotions of Gwangyang port's competitiveness, according to its international port competitiveness analysis. This study will provide both academic and policy implications with its related scholars, government, and research institutions. In addition, this will be contributed to formulating a basic theory for port competitiveness evaluation and providing a basic framework of evaluation analysis.

• Korean Journal of Plant Taxonomy
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• v.47 no.3
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• pp.264-288
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• 2017

In order to organize a new checklist for endemic vascular plants of the Korean Peninsula, 358 taxa of the Korea Forest Service and 375 taxa of the National Institute of Biological Resources were reviewed. In addition, the names of previously published endemic plants above the rank of variety were checked up to 2016. From the two lists, a total of 444 taxa were identified. Among them, 289 taxa were common on the two lists, but 69 and 86 taxa were listed only by the Korea Forest Service and by the National Institute of Biological Resources, respectively. Taxonomic documents including journal papers and dissertations were examined with regard to the 444 taxa. In some cases, opinions of Korean experts in this field were also reflected. From the results, 312 taxa in total were recognized as plants endemic to the Korean Peninsula, while 132 taxa could not be included on the endemic list. On the other hand, 48 taxa, none of which existed on the two lists, were newly listed. In conclusion, the new checklist of vascular plants endemic to Korea was confirmed, with a total of 360 taxa consisting of 64 families, 172 genera, 297 species, 4 subspecies, 51 varieties and 8 hybrids. The new common name Halla-seol-aeng-cho is given to Primula farinosa L. subsp. modesta (Bisset & S. Moore) Pax var. hannasanensis (T. Yamaz.) T. Yamaz. Sillaphyton Pimenov (Deok-u-gi-reum-na-mul-sok) is newly identified as a genus endemic to Korea. However, Pentactina Nakai could not be included on the list of Korean vascular endemic genera.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1069-1077
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• 2008

The railway abrasion measurement system have to satisfy two conditions to increase the measurement accuracy as follows. The laser region which is projected on the rail have to be extracted without the geometrical distortion. The mapping of the acquired laser region data on the rail profile have to be processed exactly. But, the conventional railway abrasion measurement system is deeply effected by the foreign substance( dust, rainwater, and so on ) on the railway or the sensitive response characteristic of the laser to the external measurement circumstance, and then the measurement errors arise from above factors. When the laser region is projected on the rail extracts from the acquired image, the interference of the light with the same frequency as the laser system occurs the serious problems. In the process of the mapping between the railway profile and the extracted laser region, the measurement accuracy is very highly effected by the geometrical distortion and the abnormal variation. In this Paper, we propose the novel method to increase the accuracy of the railway abrasion measurement dramatically. we designed and manufactured the high precision and fast image processing board with DSP Core and FPGA to measure the railway abrasion. The image processing board has the capability that the image of 1024X1280 from camera can be processed with the speed of 480 frame/sec. And, we apply the image processing algorithm base on the wavelet to extract the laser region is projected on the rail exactly. Finally, we developed high precision railway abrasion measurement system with the error range less than +/-0.5mm by which 2D image data is covered 3D data and mapped on the rail profile using the camera model and the perspective transform.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.436-440
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• 2008

Monorail is a type of LRT that a train, made with $2{\sim}4$ cars runs on single track. Monorail can be divided into two types - straddled type, running on track beam and suspended type, running suspended from track beam. After Wuppertal, world's first monorail in German, many monorails are currently operated in Australia, U.S.A, Japan etc. In macountry, it was decided to introduce monorail to 3rd line of Daegue. Daegue's 3rd line is public financial project and supported about 60% of total project cost by central government. The central government announced a standard for rubber-wheel type LRT and steel-wheel type LRT. It becomes a guide to local government willing to introduce this type of LRT. The standard for monorail hasn't announced yet although the necessity of research has grown. Korea Railroad Research Institute which has been asked to research by Ministry of Land Transport and Maritime Affairs has carried out research on standard of monorail considering domestic condition. The on-going research is described in this paper. We wish that it becomes national standard and a good guide for local government.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1916-1932
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• 2008

The railway accident is characterized by widespread and great(immerse) damage to our society when an accident occurred even if the probability of a railway accident is low. It is no doubt that the role of a rolling stock driver who are active in the first line of the rail safety driving is the most important to prevent an unexpected railway accident. Before new railway safety law being taken into effect, each railway operating organization had the responsibility of training a rolling stock driver by qualification criteria (the requirements or standards of competency), training period, probation period decided on their own standards. To train drivers driving same locomotive model, each railway operating organization had a variety of standards to draft and train trainees. Consequently, It was considered inefficient way to train and manage rolling stock drivers. However, after implementing the new railway safety law, a new system including training and evaluation process to issue driver's license on the condition that entire requirements are satisfied has been established. To prove the competency of the rolling stock driver objectively, training center and third-party evaluation center are divided individually and assigned by government office. Training center should design the training program to allot theatrical education time for different trainee group and to secure maximum practical training time utilizing simulator system to enhance the rolling stock driver's competency. This study analyzes certain conditions necessary to maximize the effectiveness and practical use of training for aquisition of a driver's license and the problems of the existing rail safety law and the ways to improve them.

• Journal of the Korea Society of Computer and Information
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• v.25 no.6
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• pp.171-181
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• 2020

This is an empirical study that analyzes factors affecting the work-family compatibility of female wage workers with underage children. The analysis was conducted with 1,113 women from the 7th wave of the Korean Longitudinal Survey of Women & Families by Korean Women's Development Institute. As for research methods, multiple regression analysis was used in order to analyze the effects of 'social support(home support, maternity protection support, childcare and education services)', 'job characteristics', 'socio-demographic variables' and 'husband characteristics' on 'work-family compatibility and conflict'. As a result, it was analyzed that the husband's support for work life, gender inequality at work and women's educational training were the factors that strengthen work-family compatibility. It was also analyzed that gender inequality, use of childcare and education facility, number of underage children, age of husband, husband's satisfaction with caring support and husband's support for work life were the factors that cause conflict between work and family. Thus, if the policy of strengthening the work-family compatibility is a long-term policy, it appears that it is necessary to supplement and strengthen policies that can reduce conflict factors in the short term. It is hoped that the results of the study will be used as objective and academic data to strengthen the maternity protection and work-family compatibility of female workers with underage children.

• Korean Journal of Psychosomatic Medicine
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• v.24 no.1
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• pp.43-53
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• 2016

Objectives : Somatic symptoms after the exposure of psychological trauma frequently developed. However, the somatic symptoms are not covered under the diagnostic criteria of posttraumatic stress disorder(PTSD) in detail, although they are often associated with social and occupational functioning and patient-doctor relationships. The aim of this article is to highlight the potential mechanisms, the common manifestations, and the treatment of the somatic symptoms. Methods : This article studied the somatic symptoms searched using academic search engines like PubMed, Scopus, Google Scholar, KoreaMed and KISS from the earliest available date of indexing to March 31, 2016. Results : The mechanism of somatic symptoms after the exposure was described as psychological and physiological aspects. Psychological mechanism consisted of psychodynamic theory, cognitive behavioral theory, and others. Physiological mechanism involved changes in neuroendocrine and immune system, autonomic nervous system and central nervous system. Somatization associated with psychological trauma manifested various health conditions on head and neck, chest, abdominal, musculoskeletal, and dermatological and immune system. Few studies described the standardization of treatment for the somatic symptoms. Conclusions : Clinicians and disaster behavioral health providers should think of the accompanying somatic symptoms during intervention of psychological trauma and PTSD. Further studies are needed on the somatic symptoms seen in psychological trauma and PTSD.

• Journal of the Korean Society of Earth Science Education
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• v.14 no.2
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• pp.173-192
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• 2021

The purpose of this study is to analyze the previous research on geological fieldwork from 2000 to 2020, examine the tasks that have been focused on, and suggest directions and implications for future geological fieldwork research. The data was conducted for the thesis searched on ScienceON and RISS in relation to geological fieldwork and journals listed in the Korean Citation Index(KCI), and the study title was analyzed using the semantic network analysis. For analysis, the data that had been pre-processed was visualized as a network by semantic network analysis, and frequency and centrality were analyzed. The centrality analysis was based on degree centrality and eigenvector centrality, and all analyzes were performed by dividing the entire study period into four periods: 2000-2005, 2006-2010, 2011-2015, and 2016-2020. As a result, research on geological fieldwork focused more on the development of geological field courses, and in particular, jeju island was actively discussed as a learning site. Also, the study was conducted on students rather than teachers, and among them, high school students showed high frequency and centrality. In addition, it can be seen that studies on the educational effect of geological fieldwork were discussed, either in connection with programs such as STEAM, free-semester program, or indirect geological fieldwork methods such as web, flash panorama, and 3D. This study is meaningful in that it suggests the direction of future research by looking back on the research on geological fieldwork that has been done so far.