• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.664-671
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• 2011

Random Walk Model can predict the sediment areas of debris flow but it must be extracted three parameters fitted topographical environment. This study developed the method to extract the optimal values of three parameters - Once flowing volume, Stopping slope and Gravity weight - for Random Walk Model. And the extracted parameters were validated by aerial photographs of the debris flowed area. To extract the optimal parameters was randomly performed, limiting the range values of three parameters and developing an accuracy decision method that is called the rate of concordance. The set of the optimal parameters was decided on highest the rate of concordance and a consistency. As a result, the optimal parameters in Bonghwa county were showed that the once flowing volume is $1.0m^3$, the stopping slope is $4.2^{\circ}$ and the gravity weight is 2 when the rate of concordance is -0.2. The validating result of the optimal parameters showed closely that the rate of concordance is average -0.2.

• 한국사회정책
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• v.20 no.2
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• pp.261-304
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• 2013

This article is aiming intensively to analyze the polarizing tendency of labour market and social integration. The polarization of labour market is being regarded as one of the hottest issues not less important than those problems of economic growth, employment, income distribution and national security etc. in the national policy. In this article, we will first follow up the important phenomena of labour market polarization and the background as well as its consequence. Especially, it asks if the present labour policy in the new government which is now being concentrated on the improvement of employment rate(from the present 63% to the 70% in the future) could deserve to diminish the polarization of labour market in korea. At one side, this article makes the special attention on the diversifying tendency of labour market and the various phenomena of fragmentation and segmentation in the labour market according to the forms and types of employment and according to the employee's status as much as the company's size. At the other side, it emphasizes that to overcome the polarization of labour market should require the wide reform from the legal measure to the improvement of the wage system, and the qualification system and the social investment as well as the human resource development. Furthermore, this article stresses the importance of integrative approach between the active market policy and the social policy instead of choosing each policy option, seperatively.

• Korean Journal of Ecology and Environment
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• v.53 no.4
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• pp.445-452
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• 2020

In this study, we carried out a distribution and migration boundary lines of chum salmon (Oncorhynchus keta) in the Milyang River. We measured the total length of dead chum salmons. As a results, 40 chum salmons were found during the study period, 25 dead salmons and 15 alive individuals. The ratio of female was 64%. We verified the migration boundary lines of chum salmons based on a sighting survey until detecting a structure that chum salmons are not able to migrate upstream. We discovered that chum salmons were not able to migrate up to 13 km in a mainstream of the Milyang River and up to 12 km in the Danjang stream (a tributary of the Milayang River) from upstream of the Yerim Bridge. Therefore, our results indicate that Milyang River should improve a river connectivity by demolishing weirs that disturb chum salmon's migration or installing appropriate fishways. Also, effective legislations are needed to retain naturality in spawning ground and micro-habitats to increase the survival rate of parrs and smolts.

• Journal of Apiculture
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• v.35 no.1
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• pp.9-19
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• 2020

The questionnaire survey for Apis cerana beekeepers and professionals on improved native bee hives was carried out and we compared the temperature, relative humidity(RH), and weight changes of 4 improved hives(Chungju, Miryang, Hanam, and Suwon) from May 1, 2019 to January 31, 2020. Beekeepers need vertical feeder, hive stand, entrance block, and separating panel as hive accessory devices. The average temperatures within brood area were kept constantly (31.3~35.1℃) and the low daily variances of temperature (≤1℃) in Chungju hive among tested hives were observed. The daily temperature variances in the separated space and on the top of winter cluster were not different among 4 hives. In correlation between the temperature of brood area and the number of combs, Chungju hive showed the highest correlation(80.4%) and between the temperature on top of winter clusters and outside temperature, 4 hives showed high positive correlation(76.8~87.1%). RH of brood area(45~60%) in all hives were kept relatively low and constant compared to the outside RH(60~85%). The stablest RH on the top of winter cluster was observed in Suwon hives (65~75%) The highest cumulative weight increase among hives and the high positive correlation(65~67%) between the change of cumulative hive weight and combs number of hives were shown in the Miryang and Chungju. Based on these results, A. cerana bees are able to manage constant temperature and RH within hives area for their colony life, which also effected by the types of hive.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.320-330
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• 2020

Fire is difficult to achieve good performance in image detection using deep learning because of its high irregularity. In particular, there is little data on fire detection in underground utility facilities, which have poor light conditions and many objects similar to fire. These make fire detection challenging and cause low performance of deep learning models. Therefore, this study proposed a fire detection model using deep learning and estimated the performance of the model. The proposed model was designed using a combination of a basic convolutional neural network, Inception block of GoogleNet, and Skip connection of ResNet to optimize the deep learning model for fire detection under underground utility facilities. In addition, a training technique for the model was proposed. To examine the effectiveness of the method, the trained model was applied to fire images, which included fire and non-fire (which can be misunderstood as a fire) objects under the underground facilities or similar conditions, and results were analyzed. Metrics, such as precision and recall from deep learning models of other studies, were compared with those of the proposed model to estimate the model performance qualitatively. The results showed that the proposed model has high precision and recall for fire detection under low light intensity and both low erroneous and missing detection capabilities for things similar to fire.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.390-397
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• 2021

The selective public-benefit direct payment is a system that provides subsidies to farmers that improve the public benefit of agriculture. However, there are limits in improving the public benefit since the current system simply integrates the prior direct payment system. Therefore, it is necessary to improve the public benefit of agriculture by reorganizing the implementation framework. This study uses the analytic hierarchy process and analytic network process to set the priority of the system and propose an implementation framework. A survey was conducted targeting 51 experts for about two months from August 2020. Study results show that the most important goal of the system is its effectiveness. The public beneficial implementation framework of the selective public-benefit direct payment is bundle type. Meanwhile, the effects of the subcategories of the bundle type lack research. Therefore, it is necessary to conduct a pilot project for the bundled type system and systematically establish policies by analyzing the effects of the pilot project. This study provided indicators about policy directions through the evaluation of the selective public-benefit direct payment (plan). The results of this study are expected to provide an objective basis for government policies related to the reform of selective public-benefit direct payment systems in the future.

• Journal of Korean Library and Information Science Society
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• v.52 no.2
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• pp.145-166
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• 2021

The study was aimed at verifying the effectiveness of Book-Coding reading education as a reader activity of older elementary school children at a time when high-dimensional thinking abilities were formed. To this end, 30 fifth-grade children of N Elementary School in N-si, Gyeonggi-do, comprised of 15 students from a reading education program using Book-Coding, and 15 students from a reading comprehension program, and applied the reading education program over a total of 12 sessions. The main results of the study are summarized as follows. First, when the effects of the convergence reading education program using Book-Coding on the logical thinking ability of the students in the upper grades in the elementary school were analyzed, all the six sub-factors of logical thinking ability, that is, conservation logic, proportional logic, variable controlling logic, probabilistic logic, correlational inference logic, and combinational logic, were proved to have statistically more meaningful difference than the group writing a book report. Second, the analysis result of the influence of the convergence reading education program using Book-Coding on the creativity of the students in the upper grades of the elementary school showed that all the 13 elements of curiosity, persistence, effectiveness, independence, adventurousness, openness, knowledge, imagination, originality, sensitivity, fluency, flexibility, and accuracy were statistically meaningfully different compared to the book report group. Third, when it was analyzed how the convergence reading education program using Book-Coding affected the creative personality of the elementary school students, all the six factors of curiosity, task commitment, independence, awareness of risk, and openness of thinking, and aesthetics were found out to have a statistically more meaningful difference than the group that wrote a book report.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.2
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• pp.84-91
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• 2022

This study investigated the behavior of out-of-plane skewed moment connections that were designed as IMFs, as per the Korean standards. A total of 14 finite element models were constructed with the consideration of two types (single- and double-sided connections) and four levels of skew angle (0°, 10°, 20°, and 30°). The results indicated that the skewed connections considered in this study met the acceptance criteria for IMFs given by the codes. However, the load-carrying capacities of skewed connections were decreased as the skew angle increased. For the connection with a skew angle of 30°, the peak load was noted to be 13% less and the energy dissipation capacity could be 26% less than that of non-skewed connection. In addition, because of the skewed nature, the stress distribution in the skewed beam flange near the connection was asymmetric and the stresses were concentrated on the beam inner flange. Column twisting induced by the skewed configuration was very small and negligible in the beam and column combination considered in this study.

• Pediatric Infection and Vaccine
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• v.29 no.1
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• pp.37-45
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• 2022

Purpose: During the coronavirus disease 2019 (COVID-19) pandemic, we conducted a Delphi survey that included the experts from the field of COVID-19 immunization in children aged 5-11 years. The aim was to organize collective expert opinions on COVID-19 vaccination in young children in the Republic of Korea, and so thus assist the vaccination policy. Methods: The panels included pediatric infectious disease specialists, preventive medicine experts, infectious disease physicians, and COVID-19 vaccine experts consulting the Ministry of Health and Welfare. The Delphi survey was conducted online using a questionnaire from February 14 to February 27, 2022. Results: The Delphi panels agreed that children were vulnerable to COVID-19, and the severity of illness was modest. Furthermore the panels reported that children with chronic illness were more susceptible to a worsening clinical course. There were generally positive opinions on the effectiveness of COVID-19 vaccination in children aged 5-11 years, and experts gathered a slightly positive opinion that the adverse events of pediatric COVID-19 were not numerous. The benefits of COVID-19 vaccination were evaluated at a level similar to the potential risks in children. Currently, the only approved mRNA platform vaccine in children seemed to be sustainable; however, the recombinant protein platform COVID-19 vaccines were evaluated as better options. Conclusions: Due to the surge of the Omicron variant and an increase in pediatric cases, the COVID-19 vaccination in young children may have to be considered. Panels had neutral opinions regarding the COVID-19 vaccination in children aged 5-11 years. Thus monitoring of the epidemiology and the data about the safety of COVID-19 vaccination should be continued.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1489-1503
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• 2022

Drone and sensor technologies are enabling digitalization of agricultural crop's growth information and accelerating the development of the precision agriculture. These technologies could be able to assess damage of crops when natural disaster occurs, and contribute to the scientification of the crop insurance assessment method, which is being conducted through field survey. This study was aimed to calculate lodged damage rate from the vegetation indices extracted by drone based RGB images for soybean. Support Vector Classifier (SVC) models were considered by adding vegetation indices to the Crop Surface Model (CSM) based lodged damage rate. Visible Atmospherically Resistant Index (VARI) and Green Red Vegetation Index (GRVI) based lodged damage rate classification were shown the highest accuracy score as 0.709 and 0.705 each. As a result of this study, it was confirmed that drone based RGB images can be used as a useful tool for estimating the rate of lodged damage. The result acquired from this study can be used to the satellite imagery like Sentinel-2 and RapidEye when the damages from the natural disasters occurred.