• Journal of Korean Society of Transportation
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• v.30 no.2
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• pp.101-116
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• 2012

Accident prediction models have been utilized to predict accident possibilities in existing or projected freeways and to evaluate programs or policies for improving safety. In this study, a traffic accident prediction model for freeways was developed for the above purposes. When selecting variables for the model, the highest priority was on the ease of both collecting data and applying them into the model. The dependent variable was set as the number of total accidents and the number of accidents including casualties in the unit of IC(or JCT). As a result, two models were developed; the overall accident model and the casualty-related accident model. The error structure adjusted to each model was the negative binomial distribution and the Poisson distribution, respectively. Among the two models, a more appropriate model was selected by statistical estimation. Major nine national freeways were selected and five-year dada of 2003~2007 were utilized. Explanatory variables should take on either a predictable value such as traffic volumes or a fixed value with respect to geometric conditions. As a result of the Maximum Likelihood estimation, significant variables of the overall accident model were found to be the link length between ICs(or JCTs), the daily volumes(AADT), and the ratio of bus volume to the number of curved segments between ICs(or JCTs). For the casualty-related accident model, the link length between ICs(or JCTs), the daily volumes(AADT), and the ratio of bus volumes had a significant impact on the accident. The likelihood ratio test was conducted to verify the spatial and temporal transferability for estimated parameters of each model. It was found that the overall accident model could be transferred only to the road with four or more than six lanes. On the other hand, the casualty-related accident model was transferrable to every road and every time period. In conclusion, the model developed in this study was able to be extended to various applications to establish future plans and evaluate policies.

• Journal of Korean Home Economics Education Association
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• v.20 no.3
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• pp.107-129
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• 2008

The purpose of this study was to get insights and data from home economics teachers for the development of an in-service educational program on practical problem focused home economics program, which was planned to be held from January 21st and to 29th, 2008. For this, focus group interview, one of qualitative research methods, was used. One session of pilot and three sessions of main focus group interview in which total of 18 from October 31st, 2007 to November 14, 2007. Home economics teachers that participated were carried out. Participants requested the followings contents of an in-service educational program regarding the practical problem focused home economics curriculum. First, most of participants strongly desired to participate in an in-service educational program when a program provided. The participants wanted to be a professional, who is able to explain logically with philosophical background and knowledge about the practical problem focused home economics curriculum. Second, participants requested the followings regarding practical problem focused home economics curriculum for the contents of an in-service educational program: philosophy of home economics, setting a perspective on each content areas, development of practical problem, watching a sample class unit, developing teaching materials and motivation stimulating questions, designing of instruction and lesson plans, class presentation and peer evaluation, constructing paper and pencil test items, and feedback from expects on the practical problem focused home economics curriculum. Third, participants wanted an in-service educational program to be a combination of theory and practice, and at least 50% of it allotted to practice. Participants thought that both peer participants and experts from university would evaluate them whether they achieved the objectives of the in-service educational program if an in-service program has to evaluate participants. Participants would evaluate an in-service educational program excellent when they become empowered to teach other home economics teachers the theoretical aspects of the practical problem focused home economics curriculum and the practical aspects as well. Based on the results of this study a framework of the 30 hours practical problem focused home economics curriculum was proposed.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.419-428
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• 2021

In order to develope a mobile-based greenhouse energy calculation program, firstly, the overall thermal transmittance of 10 types of major covers and 16 types of insulation materials were measured. In addition, to estimate the overall thermal transmittance when the cover and insulation materials were installed in double or triple layers, 24 combinations of double installations and 59 combinations of triple installations were measured using the hotbox. Also, the overall thermal transmittance value for a single material and the thermal resistance value were used to calculate the overall thermal transmittance value at the time of multi-layer installation of covering and insulating materials, and the linear regression equation was derived to correct the error with the measured values. As a result of developing the model for estimating thermal transmittance when installing multiple layers of coverings and insulating materials based on the value of overall thermal transmittance of a single-material, the model evaluation index was 0.90 (good when it is 0.5 or more), indicating that the estimated value was very close to the actual value. In addition, as a result of the on-site test, it was evaluated that the estimated heat saving rate was smaller than the actual value with a relative error of 2%. Based on these results, a mobile-based greenhouse energy calculation program was developed that was implemented as an HTML5 standard web-based mobile web application and was designed to work with various mobile device and PC browsers with N-Screen support. It had functions to provides the overall thermal transmittance(heating load coefficient) for each combination of greenhouse coverings and thermal insulation materials and to evaluate the energy consumption during a specific period of the target greenhouse. It was estimated that an energy-saving greenhouse design would be possible with the optimal selection of coverings and insulation materials according to the region and shape of the greenhouse.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1487-1495
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• 2018

In this study, we investigated collagen production and hyaluronic acid production effects for wrinkle improvement test on 50 kinds of land plants and 10 kinds of marine plants native to Jeju Island as a part of developing customized cosmetic materials. Collagen and hyaluronic acid are recognized as major factors affecting skin aging. Cerastium holosteoides var. hallaisanense Mizushima extract ($100{\mu}g/mL$) produced more than 190% of collagen in the extracts of 50 kinds of land plants. Vicia angustifolia var. segetilis K. Koch. extract ($100{\mu}g/mL$) produced more than 160% of collagen. Ftsia japonica Decne. et Planch. extract ($100{\mu}g/mL$), Euonymus japonica Thunb. extract ($100{\mu}g/mL$), Suaeda malacosperma H.Hara extract ($100{\mu}g/mL$), Elaeagnus umbelellata Thunb. extract ($100{\mu}g/mL$), Sedum oryzifolium Makino extract ($100{\mu}g/mL$), Vicia unijuga A. Br. extract ($100{\mu}g/mL$), and Brassica juncea var. integrifolia Sinsk. extract ($100{\mu}g/mL$) showed more than 140% collagen production effect. Among the 10 species of marine plants, Sargassum macrocarpum C. Agardh extract ($50{\mu}g/mL$) produced more than 190% of collagen, and Carpopeltis angusta (Harvey) Okamura extract ($100{\mu}g/mL$), Codiumcoactum Okamura extract ($100{\mu}g/mL$), and Codium tenuifolium S. Shimada, T. Tadano & J. Tanaka extract ($100{\mu}g/mL$) showed more than 140% collagen production. Suaeda malacosperma H.Hara extract ($100{\mu}g/mL$) showed the effect of producing hyaluronic acid more than 140%, and Ftsia japonica Decne. et Planch. extract ($20{\mu}g/mL$) and Wistaria floribunda A.P. DC extract ($100{\mu}g/mL$) showed more than 130% hyalunonic acid production effect. Among the 10 species of marine plants, Peyssonnelia capensis Montagne extract ($100{\mu}g/mL$) was the most effective. Carpopeltis angusta (Harvey) Okamura extract ($100{\mu}g/mL$), Codiumcoactum Okamura extract ($100{\mu}g/mL$), and Codium tenuifolium S. Shimada, T. Tadano & J. Tanaka extract ($100{\mu}g/mL$) showed more than 120% hyalunonic acid production. Jeju resources, which have good collagen and hyaluronic acid production, showed the potential to be applied to solve the skin troubles of customized cosmetics in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.2
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• pp.138-145
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• 2021

Perilla contains more than 60% of fatty acids. Linolenic acid is effective in preventing heart disease, improving learning ability, treating allergies, and preventing cancer. This study was carried out to improve the cultivation method to aid the stable production of perilla by developing a suitable inter-cropping system with sesame in the central region as well as to report a suitable planting time. The test results are summarized as follows. As the planting time of perilla in the inter-cropping system with sesame was delayed, the number of clusters and capsules decreased. The perilla yields in this system showed significant differences compared to that with the previous crops (sesame varieties) and planting period. The yield of perilla was significantly lower in the characteristic-Type B variety than in the characteristic-Type A variety and decreased significantly as the planting time was delayed. With regards to the quality characteristics of perilla, such as crude protein, crude fat, etc., there were no differences between previous perilla crops and those inter-cropped with sesame. The perilla composition did not show any difference during the planting period; however, with delay in the planting time, crude protein content increased but crude fat content decreased. Yield of perilla was 38% higher in a two-row (40 x 40 cm) system, compared to a single-row cultivation (110 x 20 cm) of perilla inter-cropped with sesame. These results suggest that the suitable method for inter-cropping perilla with sesame in the central region is to sow the characteristic-Type A variety in early May, and cultivate the perilla in two lines (40 x 40 cm) in mid-June. This was judged to be the best cultivation method in the central region.

• Journal of the Society of Disaster Information
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• v.17 no.1
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• pp.97-111
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• 2021

Purpose: It is expected that various infrastructures diagnosis equipment will be needed as infrastructures management is strengthened to implement the Framework Act on Sustainable Infrastructure Management. It is necessary for a certification system to supply certified products of a reasonable level in accordance with market requirements for various convergence equipment. This paper deals with the introduction of certification system of inspection and diagnosis equipment for infrastructure using advanced technologies. Method: The basic elements, systems and procedures of certification system were reviewed through analyzing and comparing the existing similar certification system in Korea. In addition, a survey was conducted on a catalog method and the minimum performance criterion (sampling survey and complete enumeration survey) to equipment developers (manufacturers), clients and equipment users. Result: This survey showed that clients preferred complete enumeration method on the basis of minimum performance, and equipment users also preferred complete enumeration survey and sample survey, for minimum performance, at a similar rate. On the other hand, equipment developers preferred the catalog method. Conclusion: Clients and users who are the users of the diagnostic equipment preferred the minimum performance criterion because their trust in quality is important. On the other hand, developers(manufacturers) preferred the catalog method which adopts self certification because it is regulated in developing various products. There is no specific plan for the minimum performance standards required for the introduction of the method which users demand, at present. In addition, it is not desirable to force to introduce a certification system because it requires a considerable period of study to prepare the specific standards. Therefore, it is appropriate to operate the system for a certain period of time centering around the catalog method for the stable and continuous development of the infrastructure diagnosis and test equipment market in Korea. Also, it is effective to expand and develop the certification system to the extent that it minimizes the impact on the market when specific plans for the standards are prepared in the future.

• Journal of Korean Home Economics Education Association
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• v.32 no.4
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• pp.81-101
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• 2020

The purpose of this study is to develop and implement a process-based evaluation program with the theme of school space design in the housing area of the middle school home economics. In order to achieve For thispurpose, a process-based evaluation program based on the theme of school space design was developed following the ADDIE instructional design model, and the program was executed to a total of 93 students. A questionnaire survey and in-depth interview were conducted for the evaluation of the program. The results of this study are as follows. First, based on the results of a 2015-Revised Curriculum analysis, a school space design program evaluation plan was established, and two evaluation tasks were developed. Accordingly, scoring criteria were prepared and 8 evaluation materials for students and 2 evaluation materials for teachers were developed. A total of 9 sessions were developed for teaching and learning activities and evaluation-linked operation procedures to perform evaluation tasks. As a result of an expert validity test for the program, all items were verified to be appropriate in content validity and content composition with an average of 3.6 to 4 points (4 points). Second, after conducting the school space design program, a survey on students were conducted, and as a result, all three areas of school space design class, process-based evaluation, interest scored high in average scores of 4.12 to 4.27 out of 5. According to the survey and interview results, the program provided new learning opportunities for school space design, the students were able to reach the suggested achievement goals, and the self-assessment, peer evaluation and teacher feedback positively affected the students during the learning process so that they could reflect on their learning and actively participate in the subsequent learning activity. This study has a limitation in generalizability in that the program was conducted on a limited number of students, and future studies are expected to expand the scope in terms of research participants, evaluation criteria, and school space design classes. This study laid the foundation for theory and practice by developing and implementing a process-based evaluation program for home economics education, and it has contribution in that it suggested the possibility that teachers and students can take the initiatives in school space design, focusing on the housing content elements of home economics.

• Korean Journal of Optics and Photonics
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• v.33 no.4
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• pp.167-176
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• 2022

Adaptive optics (AO) systems compensate for atmospheric disturbance, especially phase distortion, by introducing counter-wavefront deformation calculated from real-time wavefront sensing or prediction. Because AO system implementations are time-consuming and costly, it is highly desirable to estimate the system's performance during the development of the AO system or its parts. Among several techniques, we mostly apply statistical analysis, computational simulation, and optical-bench tests. Statistical analysis estimates performance based on the sum of performance variances due to all design parameters, but ignores any correlation between them. Computational simulation models every part of an adaptive optics system, including atmospheric disturbance and a closed loop between wavefront sensor and deformable mirror, as close as possible to reality, but there are still some differences between simulation models and reality. The optical-bench test implements an almost identical AO system on an optical bench, to confirm the predictions of the previous methods. We are currently developing an AO system for a 1.6-m ground telescope using a deformable mirror that was recently developed in South Korea. This paper reports the results of the statistical analysis and computer simulation for the system's design and confirmation. For the analysis, we apply the Strehl ratio as the performance criterion, and the median seeing conditions at the Bohyun observatory in Korea. The statistical analysis predicts a Strehl ratio of 0.31. The simulation method similarly reports a slightly larger value of 0.32. During the study, the simulation method exhibits run-to-run variation due to the random nature of atmospheric disturbance, which converges when the simulation time is longer than 0.9 seconds, i.e., approximately 240 times the critical time constant of the applied atmospheric disturbance.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.104-115
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• 2022

Purpose: Infrastructure inspection and its diagnostics technique have been rapidly developing recently. Therefore, it is important to secure the reliability of diagnostic equipment, and this paper deals with inspection of diagnostic equipment, introduction to a certification system and development plans for infrastructure. Method: Several certification systems are established and introduction plans are reviewed through experts by synthesizing the contents of certification research for existing infrastructure diagnosis equipment. In addition, the revision of the law for introduction of the system is reviewed, detailed operation regulations are prepared and phased development plans are reviewed, which are based on the operation scenario. Result: Inspection and certification plans were constructed through four routes in order to consider infrastructure inspection and diagnostic equipment in use, and new diagnostic equipment using state-of-the-art technology. Furthermore, market confusion depending on the introduction of a new certification system is minimized and reliability is secured by transforming a simple inspection system in the short term into a formal certification system in the long term. The law amendments according to the introduction of the system were reviewed and detailed operation regulations were developed. Also, phased development plans, which are based on the long-term development scenario including manpower, infrastructure and specifications, were presented. Conclusion: It is important to secure reliability through the distribution and certification of diagnostic equipment using 4th industrial technology to strengthen the safety management of infrastructure at the national level since the infrastructure is various in type and increasingly large in size. It is also essential to train human resources who can use new technology with inspection and diagnosis system in order to enhance the safety management of all infrastructures. Moreover, it is necessary to introduce a regular inspection system for infrastructure that combines loT technology in the long-term point of view and to promote the introduction by giving active incentives to institutions that actively accept it.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.295-304
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• 2022

The purpose of this study is to detect the sorghum panicle using YOLOv5 based on RGB images acquired by a unmanned aerial vehicle (UAV) system. The high-resolution images acquired using the RGB camera mounted in the UAV on September 2, 2022 were split into 512×512 size for YOLOv5 analysis. Sorghum panicles were labeled as bounding boxes in the split image. 2,000images of 512×512 size were divided at a ratio of 6:2:2 and used to train, validate, and test the YOLOv5 model, respectively. When learning with YOLOv5s, which has the fewest parameters among YOLOv5 models, sorghum panicles were detected with mAP@50=0.845. In YOLOv5m with more parameters, sorghum panicles could be detected with mAP@50=0.844. Although the performance of the two models is similar, YOLOv5s ( 4 hours 35 minutes) has a faster training time than YOLOv5m (5 hours 15 minutes). Therefore, in terms of time cost, developing the YOLOv5s model was considered more efficient for detecting sorghum panicles. As an important step in predicting sorghum yield, a technique for detecting sorghum panicles using high-resolution RGB images and the YOLOv5 model was presented.