• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.2
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• pp.147-156
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• 2024

The sustainable management and enhancement of marine resources are becoming increasingly important issues worldwide. This study was conducted in response to these challenges, focusing on the development and performance comparison of fish detection and classification models as part of a deep learning-based technique for assessing the effectiveness of marine resource enhancement projects initiated by the Korea Fisheries Resources Agency. The aim was to select the optimal model by training various sizes of YOLOv8-Seg models on a fish image dataset and comparing each performance metric. The dataset used for model construction consisted of 36,749 images and label files of 12 different species of fish, with data diversity enhanced through the application of augmentation techniques during training. When training and validating five different YOLOv8-Seg models under identical conditions, the medium-sized YOLOv8m-Seg model showed high learning efficiency and excellent detection and classification performance, with the shortest training time of 13 h and 12 min, an of 0.933, and an inference speed of 9.6 ms. Considering the balance between each performance metric, this was deemed the most efficient model for meeting real-time processing requirements. The use of such real-time fish detection and classification models could enable effective surveys of marine resource enhancement projects, suggesting the need for ongoing performance improvements and further research.

• The korean journal of orthodontics
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• v.18 no.2
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• pp.421-433
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• 1988

The purpose of this study was to investigate the characteristics of craniofacial morphology in adult with crowded dentition. The craniofacial morphology associated with normal and crowded of mandibular dentition was studied in lateral cephalometric radiograph obtained from 145 subjects grouped 44 males and 40 females in normal group, 33 males and 28 females in crowded group. The conclusions were as follows: Means, standard deviations and facial polygons from measurements were obtained from normal and crowded groups. Palatal plane to SN, occlusal plans to SN, mandibular plane to SN, mandibular plane to palatal plane and gonial angle measurements of crowded group were significantly different from normal group and were larger than normal group. SNA, SNB measurements of crowded group were significantly different from normal group and were smaller than normal group. Significant differences were observed between normal group and crowded groups on the basis of $SN/{\underline{1}}$, PP/1, $MP/{\bar{1}}$, and compared with normal group, upper incisors of crowded group were inclined more labially, whereas lower incisors of crowded group were inclined more lingually. Posterior facial height and ramal height were shorter in males of crowded group than those of normal group. Posterior facial height, mandibular length and posterior cranial base length were shorter in females of crowded group than those of normal group. Anterior facial height was longer in females of crowded group than those of normal group.

• The korean journal of orthodontics
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• v.28 no.1 s.66
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• pp.75-83
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• 1998

This study was done to recognize the importance of errors in measurements of cephalometric radiograph and to find the anatomical structures those need special care to select as a reference points through the detection of the systematic errors and estimation of random errors. For this purose, 100 cephalometric radiographs were prepared by usual manner and 61 reference points, and 130 measurement variables were established. Measurement errors were detected and estimated by the comparison of the 25 randomly-selected samples for repeated measurements with the main sample. The following results were obtained : 1. In comparison of the repeated measurements, there were statistical significant differences in 24 variables which were 18.4% of 130 total variables. 2. The frequency of the difference in identification of the reference points between the repeated measurements was very high in the root apex of upper incisor(as), the most posterior wall of maxilla(tu), soft tissue nasion(n'), soft tissue frontal eminence(ft), and ad3 in airway. 3. After correction of reference points marking until the level of below 5% significance, the range of random errors were from 0.67 to 1.71 degree or mm. 4. The variable shown the largest random error was the interincisal angle(ILs-ILi). 5. Measurement errors were mainly caused by the lack of precision in anatomic definitions and obscure radiographic image. From the above results, the author could find the high possibility of errors in cephalometric measurements and from this point, we should include error analysis in all the studies concerning measurments. In is essential to have a concept of error analysis not only for the investigator but also for a reader of other articles.

• Sleep Medicine and Psychophysiology
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• v.1 no.1
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• pp.47-59
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• 1994

Objectives: The main purpose of this study was to investigate the possible differences in sleepiness, performance, and body temperature during the night between morning(M) and evening(E) type subjects. Methods: After a survey study, to verify the validity and reliability of the Korean translation of the Home' and $\ddot{O}stberg's$ Morningness-Eveningness Questionnaire(1976), 8 extreme M-type subjects(3males, 5 females) and 8 extreme E-type subjects(3 males, 5 females) were selected from the university student population who had participated in the survey study. All subjects underwent sleep latency test and a battery of performance tests at intervals of 2 hours through the night, from 23:00 to 07:00. Oral temperature of each subject was taken every hour from 21 : 00 to 8 : 00. Between the testing times, the experimenters ensured that subjects remained awake. Results: More profound sleepiness was found in the M-type compared to the E-type throughout the night, with significant differences in sleepiness occuring at 23:00 and 01:00 hours. Overall performance efficiency tended to be lower through, the night in the M-type than in the E-type on all tests. A difference in time of temperature minimum between the two types was not noteworthy. Rather, there appeared to be a substantial difference in temperature level during the declining phase, with the temperature of the M-type being lower than that of the E-type. Conclusions: These results indicate the existance of a temporal relationship between sleepiness, perfonnance and body temperature during night work. Since the M-type exhibited greater sleepiness and lower performance efficiency overnight than the E-type, it may be assumed that the E-type is more suitable for and tolerable to night work. There was some discussion of the limitations in generalizing these results together with some suggestions for future studies.

• Journal of Animal Environmental Science
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• v.1 no.2
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• pp.145-153
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• 1995

This study was conducted to determine the effects of non-climatic environmental factors on performances and behavioural patterns of growing pigs. Two hundred and seventy growing pigs were confined and administered with three levels of spaces per pig(0.33, 0.44 and 0.66$m^2$) and three different numbers of pigs per pen(12, 15 and 18 pigs) from 30kg to 60kg body weight. This study was designed by using 3 $\times$ 3 factorial arrangement(three levels of spaces $\times$ three different numbers of pigs) and investigated the effects of main factors and the relationship between each factors. The result of this study were summarized as follows; 1. The 0.44$m^2$ of floor space per pig improved(p<0.01) the weight gain and the feed/gain during the growing phase. 2. The 15 pigs per pen showed the faster gain and improved feed/gain than the 12 or 18 pigs per pen during the growing phase(p<0.05). 3. The reduction of floor space of growing pigs caused the reduction of resting, non-aggressive social behaviour but eating, aggressive behaviour was increased(p<0.01). 4. Group size affected the behavioural patterns significantly(p<0.01) of growing pigs. The aggressive and eating behaviour increased but resting behaviour decreased by crowding in the growing pigs. 5. Therefore we concluded that growing pigs need 0.44$m^2$ per pig and 15 pigs per pen for the better raising condition.

• Journal of Oral Medicine and Pain
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• v.24 no.1
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• pp.25-36
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• 1999

저자는 이하두정방사선사진 (願下頭頂放射線寫眞, submentovertex radiographs)을 이용하여 하악과두의 수평각과 측두하악장애와의 연관성을 평가하고자 측두하악장애의 병력 및 증상이 없고, 자연치열로 형성된 정상교합을 가진 성인 34명과 전북대학교병원 구강내과에 내원한 측두하악장애환자 38명을 대상으로, 환자군을 임상검사 및 방사선학적 검사를 통해 편측 정복성 관절원판 전방변위 환자군, 양측 정복성 관절원판 전방변위 환자군 및 편측 비정복성 관절원판 전방변위 혹은 골관절염 환자군으로 세분한 후, 좌우측 외이도의 위치를 확인할 수 있도록 소강구 (小鋼球)가 내재된 장치물을 이용하여 채득한 규격화된 이하두정방사선사진상에서 하악과두의 내측극과 외측극을 이은 선과 양측 외이공에 위치한 소강구를 이은 선으로부터 하악과두의 수평각을 측정하였다. 평가 결과 정상군에서의 좌(평균 25.3도), 우(평균 24.8도)측 하악과두의 수평각 (평균 25.0도)은 유의한 차이를 보이지 않았으며 환자군에서는 이환측 하악과두의 수평각 (평균 28.5도)이 비이환측 하악과두 (평균 26.2도)보다 유의성있게 증가된 수치를 보였다 (p<0.05). 또한 환자군 (평균 27.55도)에서의 하악과두의 수평각이 정상군 (평균 25.0도)에서 보다 유의하게 증가된 수치를 보였다 (p<0.05). 임상적으로 세군으로 구분된 환자군의 경우, 각군의 이환측 또는 비이환측, 각 군을 합한 이환측 또는 비이환측의 경우에 있어서도 정상군에서 보다 하악과두 수평각이 유의성있게 증가된 수치를 보였다 (p<0.05). 세가지로 구분된 환자군 각각의 상호 비교에 있어서는 유의성있는 차이를 나타내지 않았다. 그리고 편측으로 이환된 환자군에서의 이환된 수평각 (평균 29.1도)은 비이환측 (평균 26.2도)보다 유의성있게 증가된 수치를 보였으나 (p<0.05), 양측으로 이환된 환자군에서의 좌우측 수평각은 유의한 차이를 보이지 않았다. 이로써 측두하악장애의 진단 차원에서 측두하악장애를 유발하는 여러 요소 중외 하나로 하악과두 수평각에 대한 평가가 고려되어야 할 것으로 사료된다.

• Informatization Policy
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• v.18 no.4
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• pp.42-58
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• 2011

This paper starts from one question: what are the key factors of the web accessibility policy, which is significant for realizing equity in the web and enhancing human dignity in the information society. To find significant factors for complying with web accessibility, this paper analyzes panel data of 16 Korean local governments (for five years: 2004-2009) according to the research design which is based on the demand and supply balance model and consists of four variables : 'legal and institutional environment (including legal infrastructure)', 'financial foundation (fiscal self-reliance ratio)', 'policy inputs (amount of imformatization budget, employee of information experts)'and 'policy demand (internet usage rate, the number of disabled people and elderly people)'. From the results of this study, this paper can explain the mechanism and impact factors on the web accessibility policy of Korean local governments. Some factors are critical to improve web accessibility: (1) the importance of policy demand, (2) the importance of policy inputs, (3) the importance of legal and institutional environment. Finally, this paper concludes with some suggestions to enhance the web accessibility capacity for Korean local governments: (1) improve awareness on web accessibility, (2) develop a standard and invest R&D on web accessibility, (3) foster experts in web accessibility.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.154-160
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• 2006

There wasn't very successful practice cases for the quantity take-off based on the CAD system since the CAD system is used in the construction industry more than 20 years in Korea. It was also not easy to use 3D CAD system in design management and cost management in the construction industry although 3D CAD system is very successful in the manufacturing industry for those areas recently. It is important to construct 3D libraries and to supply those libraries for the designers in time. Architectural work is a kind of creative work. So, Architects like to create their own model. Unlike the manufacturing industry, 3D CAD system can not be survived in the construction industry without new 3D objects supply in the right time. Moreover, the estimation system for 3D must support the schematic design phase, detailed design phase and construction design phase. The product called "Constructor" of Graphisoft consist of modeller, estimator and scheduler based on 3D model. We applied the system to a real project and compared the estimation result and we made a very successful case study.

• Korean Journal of Construction Engineering and Management
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• v.16 no.3
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• pp.11-23
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• 2015

Construction Management(CM) and Building Information Management(BIM) have a lot in common that they need to establish a cooperation system among different disciplines and promote smooth communication among project stakeholders throughout the project life-cycle. BIM can be an effective information management tool for CM's business and improve their service value. However, BIM uses by Construction Managers(CMr) are very limited. The objective of this study is to analyze the intention of CMrs to adopt BIM and establish effective BIM use strategy in the CMr's point of view. This study utilizes Technology Acceptance Model(TAM) as a research method, and the results show that 1) CMrs think it is more important whether BIM is required to be adopted in their business process at the social or industry level than that BIM can improve their personal competence, recognition, and impressions through their voluntary BIM adoption; 2) that CMrs think it is important to figure out business processes where BIM can be smoothly incorporated; and 3) that CMrs hesitate the use and trial of BIM in their realworld business although they agree that BIM needs to be eventually adopted in their business in the future. Based on these results, directions for establish a strategy for BIM adoption were proposed at the CMr's point of view

• Resources Recycling
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• v.11 no.4
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• pp.27-36
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• 2002

The clinker of which main component was calcium-chloroaluminate ($l1CaOㆍ7Al_2$$O_3$ㆍ$CaCl_2$), was synthesized with the bottom ash of municipal solid waste incinerator ash. The hydration mechanism and synthesis temperature of calcium-chloro-aluminate were investigated. The synthesized clinker was blended with a cement. It was substituted with 3～13 wt.% for clinker and $CaSO_4$ of ordinary portland cement. The compressive strength and the content of leached heavy metals of its mortar were measured. Calcium-chloroaluminate was synthesized above $800^{\circ}C$ and its main hydrate was ettringite ($3CaOㆍAl_2$$O_3$ㆍ$3CaSO_4$ㆍ$32H_2$O). The calcium-chloroaluminate was also synthesized above $800^{\circ}C$ with the bottom ash of which size fraction was below 30 mesh mainly. The compressive strength of the blended cement mortar was increased as the additive content of the clinker synthesized from the bottom ash was increased by 11 wt.%. The concentration of heavy metals leached from each mortar was satisfied with the value of the environmental standards and regulations.