• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.63-70
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• 2002

In tunnel construction, the information on the rock quality and the location of fault or fracture are crucial for economical design of support pattern and for safe construction of the tunnel. The grade of rock is commonly estimated through the observation with the naked eye of recovered cores in drilling or from physical parameters obtained by their laboratory test. Since drilling cost is quite expensive and terrains of planned sites for tunnel construction are rough in many cases, however, only limited information could be provided by core drilling Electrical resistivity and EM surveys may be a clue to get over this difficulty. Thus we have investigated electrical resistivity and EM field data providing regional Information of the rock Quality and delineating fault and fracture over a rough terrain. In this paper, we present some case histories using electrical resistivity and EM survey for the site investigation of tunnel construction. Through electrical resistivity and EM survey, the range and depth of coal seam was clearly estimated, cavities were detected in limestone area, and weak zones such as joint, fault and fracture have been delineated.

• 농촌계획
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• 제26권2호
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• pp.1-12
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• 2020

This study aimed to define characteristics of mountain village landscapes perceived by locals to sustainably preserve and manage mountain village landscapes. We selected landscape resources of mountain villages by reviewing previous studies and conducting field surveys and surveyed mountain villages' locals to investigate the characteristics of their perceptions of the mountain village landscapes. The surveys were conducted from March to October 2019, in the form of 1:1 questionnaire survey. In consequence, highly reliable 150 responses were analyzed. IPA method(Revised Importance-Performance Analysis) was used in the analysis. It is found that, in landscapes, the first quadrant is 'Cultivated land, Forest', the second quadrant is 'Coastal, Forestry and Agriculture Facility', the third quadrant is 'Forest Service·Profitable Facility, Settlement, History and Culture', and the fourth quadrant is 'Riparian, Street'. In conclusion, locals of mountain villages are perceiving the mountain village landscapes based on their livelihoods and daily lives, and the mountain village landscapes are closely related to their lives. The results of this study are expected to be utilized as fundamental resources in establishing policies regarding sustainable conservation and management of mountain village landscapes which led by locals.

• Journal of Platform Technology
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• 제11권2호
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• pp.66-75
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• 2023

첨단장비 도입 및 기술의 발전으로 수문조사 측정 기술은 향상되었으나 여전히 수문조사 시 많은 인력과 시간이 필요하며, 업무 규모와 범위에 비해 투입되는 인력은 매우 제한적이다. 또한, 자동유량 측정시설이 운영되고 있지만 현장 조건의 제한되기 때문에 전국으로 확대하기가 어렵다. 따라서 수문조사를 위해 측정 기술 자체보다는 운영 인프라 및 환경 개선이 필요하다. 또한 유량조사 측면에서 수위-유량 관계식의 정확도 재고와 업무 효율성 증진을 위해 실시간 수위 정보를 이용한 조사 스케줄링이 필요하다. 따라서 본 논문에서는 국내 수문조사 관련 연구 파악 및 수문조사의 경제성과 효율성 증대를 위하여 Open API 기반의 실시간 수위 정보를 활용한 수문조사 스케줄링 시스템을 구현하였다.

• 한국수산과학회지
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• 제57권3호
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• pp.278-291
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• 2024

This study performed three research methods (destructive, non-destructive, and panoramic image analysis) to determine the most useful for identifying seaweed habitat characteristics. Panoramic images are suitable for understanding the overall seaweed distribution. The composition of the main dominant seaweed species showed a significant difference between the destructive and non-destructive methods using Quadrat. The destructive method showed Rhodophyta dominance, whereas the non-destructive was showed Phaeophyta as dominant. Destructive methods are disadvantageous because they destroy natural communities in sea areas where bleaching is severe. Non-destructive methods are disadvantageous because of the difficulty in analyzing small species. Performing 10 surveys using a non-destructive method was found to explain up to 80% of the species identified by the destructive method. However, considering the difficulty of field investigation, repeating the investigation with non-destructive methods at least 6-7 times is necessary to ensure that more than 60% of the destructive methods can be interpreted. To understand the distribution of oceanic marine algae, performing both destructive and non-destructive surveys are necessary, as each has its own merits and demerits.

• 대한원격탐사학회지
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• 제40권1호
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• pp.93-101
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• 2024

Accurate field crop classification is essential for various agricultural applications, yet existing methods face challenges due to diverse crop types and complex field conditions. This study aimed to address these issues by combining support vector machine (SVM) models with multi-seasonal unmanned aerial vehicle (UAV) images, texture information extracted from Gray Level Co-occurrence Matrix (GLCM), and RGB spectral data. Twelve high-resolution UAV image captures spanned March-October 2021, while field surveys on three dates provided ground truth data. We focused on data from August (-A), September (-S), and October (-O) images and trained four support vector classifier (SVC) models (SVC-A, SVC-S, SVC-O, SVC-AS) using visual bands and eight GLCM features. Farm maps provided by the Ministry of Agriculture, Food and Rural Affairs proved efficient for open-field crop identification and served as a reference for accuracy comparison. Our analysis showcased the significant impact of hyperparameter tuning (C and gamma) on SVM model performance, requiring careful optimization for each scenario. Importantly, we identified models exhibiting distinct high-accuracy zones, with SVC-O trained on October data achieving the highest overall and individual crop classification accuracy. This success likely stems from its ability to capture distinct texture information from mature crops.Incorporating GLCM features proved highly effective for all models,significantly boosting classification accuracy.Among these features, homogeneity, entropy, and correlation consistently demonstrated the most impactful contribution. However, balancing accuracy with computational efficiency and feature selection remains crucial for practical application. Performance analysis revealed that SVC-O achieved exceptional results in overall and individual crop classification, while soybeans and rice were consistently classified well by all models. Challenges were encountered with cabbage due to its early growth stage and low field cover density. The study demonstrates the potential of utilizing farm maps and GLCM features in conjunction with SVM models for accurate field crop classification. Careful parameter tuning and model selection based on specific scenarios are key for optimizing performance in real-world applications.

• 지질공학
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• 제26권3호
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• pp.339-352
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• 2016

지하 매질의 물리적인 성질을 정확히 평가하기 위한 가장 일반적인 방법은 해당 지점에서 시추하여 채취한 암편을 대상으로 해석한 지질공학적인 실내시험 결과와 시추공 안에 삽입한 탐사 기구를 통해 얻은 지구물리학적인 자료를 함께 복합적으로 해석하는 것이다. 이 연구에서는 충북 증평의 지질학습장으로 예정된 시험부지 중의 한 곳에서 시추공 탐사 대신 수집한 지표 탄성파탐사(굴절법 및 표면파법) 자료로부터 얻은 P파 및 S파 속도구조와 이를 토대로 작성된 포아송 비 단면을 통해 노두에 좁은 폭으로 드러난 암석 환경(적색퇴적암, 회색화산암, 풍화 화산암) 및 접촉선에서 관찰된 단열, 파쇄대가 확인되는지 알아보았다. 또한 탐사 지역에 주로 분포하는 회색 화산암과 적색 퇴적암을 대상으로 지표지질 조사와 실내 지질공학 실험을 수행하였다. 탐사자료에서 평가된 동적 탄성계수 영률은 지질공학 자료의 정적 탄성계수보다 높았다. 실내 시험에서 회색화산암에 비해 공극률이 작고 함수비가 작은 것으로 평가된 적색퇴적암은 추가적으로 건기와 우기에 실시한 전기탐사(비저항 및 자연전위) 결과에서 건우기와 관계없이 상대적으로 전기비저항이 높고 그 변화 폭이 매우 작은 영역으로 확인되었다. 특히 높은 함수비와 공극률을 갖는 풍화된 회색 화산암과 함께 접촉선에서 좁게 발달한 단열 파쇄대가 우기 때의 충전율을 높이는 열린 통로의 역할을 한 것으로 해석된다.

• 대한치위생과학회지
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• 제4권1호
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• pp.29-37
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• 2021

Background: The selection of an occupation is typically based on individuals' personalities and the characteristics of occupations, which significantly affect occupational consciousness. The present study aimed to enhance the occupational achievement level of and provide fundamental data for student counseling in order to develop competitive professional workers by understanding the occupational consciousness of freshmen and motivating them as dental hygienists with career development plans, as freshmen majoring in dental hygiene eventually play a significant role in the field of dentistry as dental hygienists. Methods: The surveys were distributed to 160 freshmen in the dental hygiene department and were subsequently collected. The data from 142 surveys were used for analysis, as 18 surveys were excluded due to insincere responses. The survey contents included questions related to major selection and satisfaction, including motives for selecting a dental hygiene major, prior knowledge on a dental hygiene major and a career as a dental hygienist, satisfaction level of the major, and reasons for dissatisfaction in cases if applicable, as well as questions related to occupational consciousness, including career prospects for dental hygienists, opinions on the occupation, and conditions of job selection. Results: High employment rate with good salary level ranked highest (43.7%) among motives to apply the dental hygiene major, followed by the desire to be a professional worker (21.1%) and recommendation by acquaintances. Of those who responded, 50.7% indicated a normal level of satisfaction with the major, and 69.9% responded that they had prior knowledge regarding the dental hygiene major and/or field of dental hygiene. These results may be due to youth unemployment and the occurrence of job preparation immediately after students enter university, which is a result of the difficulty in job seeking. In terms of career prospects, 48.6% of students responded with "growing a little bit," followed by "growing a lot" (28.9%), "no difference from now" (21.1%), and "other" (1.4%). Regarding opinions on the occupation, 65.5% responded that occupation was an tool with which to make and income or a living, 23.2% responded that occupation was for dreams and self-realization, and 11.3% responded that occupation was for success in life and maintaining social status. Regarding the conditions of job selection, the responses included that the workplace had good working conditions (39.4%), good interpersonal relationships (21.8%), and a higher salary (18.3%). This may reflect the change in work ethics among university students, according to the trend of the times. Conclusion: Based on the results of the present study, we found that educational guidance to enhance the level of satisfaction with the major, and career guidance to understand and apply the clear vision and long-term job security are necessary.

• 수산해양기술연구
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• 제56권3호
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• pp.265-276
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• 2020

The objective of this study is to develop education programs for cultivating smart aquaculture experts through a education demand survey of industries, high school students, university (graduate) students and field workers. The industry demand analysis was conducted as an in-depth interview on representives from seven companies. Education demand surveys were conducted on 96 students and field workers in the Jeonnam region. Results on the demand survey were analyzed using frequency analysis and cross-analysis. The company representatives responded that they want to participated in internship and retraining programs to proactively secure manpowers with convergence capabilities about smart aquaculture. Seven companies preferred manpowers with basic competencies on ICT (Information and Communications Technologies) or aquaculture. The most respondents in the demand survey want to participate in the education program for experience on advanced technology, self-development and enhancement of work capability. On the other hand, some respondents said that the education is time-consuming and that the education program does not fit their level. Thus, the education program should be developed in a way to minimize the spatial and temporal limitations of education targets and to improve understanding of non-majors by reflecting the demands of human resources in the industrial field.

• 천문학회지
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• 제38권2호
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• pp.187-190
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• 2005

The Cosmic Evolution Survey (COSMOS) is a Hubble Space Telescope (HST) treasury project. The COSMOS aims to perform a 2 square degree imaging survey of an equatorial field in I(F814W) band, using the Advanced Camera for Surveys (ACS). Such a wide field survey, combined with ground-based photometric and spectroscopic data, is essential to understand the interplay between large scale structure, evolution and formation of galaxies and dark matter. In 2004, we have obtained high-quality, broad band images of the COSMOS field (B, V, r', i', and z') using Suprime-Cam on the Subaru Telescope, and we have started our new optical multi-band program, COSMOS-21 in 2005. Here, we present a brief summary of the current status of the COSMOS project together with contributions from the Subaru Telescope. Our future Subaru program, COSMOS-21, is also discussed briefly.

• 대한통합의학회지
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• 제1권1호
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• pp.77-85
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• 2013

Purpose : The purpose of this study was to investigate the fieldwork satisfaction of Dept. of Health-related students, and to ascertain a change of perception on deciding on a course after fieldwork, and on a desired field and facility. Methods : Structured questionnaires were distributed to student of Dept. of Health-related(Occupational therapy, Physical therapy, Dental hygiene) from March 2 to April 30 of 2011. The questionnaires of 150 respondents were analyzed through frequency analyses, cross- and multi-reply analyses using SPSS ver. 12.0. Results : In fieldwork satisfaction, highly satisfied items were diversity of therapeutic equipment and tools, regular education, and recognition of the importance of fieldwork. The awareness of their decisions on employment and desired field changed positively for 52.7% students and negatively for 13.3%. Conclusion : Based on the results of this study, we identified that the awareness of one's decision on employment and desired field changes through fieldwork.