• Title/Summary/Keyword: 연구모델

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Prediction of Air Temperature and Relative Humidity in Greenhouse via a Multilayer Perceptron Using Environmental Factors (환경요인을 이용한 다층 퍼셉트론 기반 온실 내 기온 및 상대습도 예측)

  • Choi, Hayoung;Moon, Taewon;Jung, Dae Ho;Son, Jung Eek
    • Journal of Bio-Environment Control
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    • v.28 no.2
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    • pp.95-103
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    • 2019
  • Temperature and relative humidity are important factors in crop cultivation and should be properly controlled for improving crop yield and quality. In order to control the environment accurately, we need to predict how the environment will change in the future. The objective of this study was to predict air temperature and relative humidity at a future time by using a multilayer perceptron (MLP). The data required to train MLP was collected every 10 min from Oct. 1, 2016 to Feb. 28, 2018 in an eight-span greenhouse ($1,032m^2$) cultivating mango (Mangifera indica cv. Irwin). The inputs for the MLP were greenhouse inside and outside environment data, and set-up and operating values of environment control devices. By using these data, the MLP was trained to predict the air temperature and relative humidity at a future time of 10 to 120 min. Considering typical four seasons in Korea, three-day data of the each season were compared as test data. The MLP was optimized with four hidden layers and 128 nodes for air temperature ($R^2=0.988$) and with four hidden layers and 64 nodes for relative humidity ($R^2=0.990$). Due to the characteristics of MLP, the accuracy decreased as the prediction time became longer. However, air temperature and relative humidity were properly predicted regardless of the environmental changes varied from season to season. For specific data such as spray irrigation, however, the numbers of trained data were too small, resulting in poor predictive accuracy. In this study, air temperature and relative humidity were appropriately predicted through optimization of MLP, but were limited to the experimental greenhouse. Therefore, it is necessary to collect more data from greenhouses at various places and modify the structure of neural network for generalization.

Perception of Science Teachers on Integrated Science Practice (통합과학 실행에 대한 과학 교사의 인식)

  • Kim, Hyunjung;Ahn, Yumin
    • Journal of The Korean Association For Science Education
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    • v.39 no.2
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    • pp.187-195
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    • 2019
  • The purpose of this study is to diagnose the operation status of high school integrated science newly introduced in the 2015 revised national curriculum and first applied in 2018, to examine teachers' perception on the new educational policy, and then based on this, extract implications for settling down the policy. A survey was administered to science teachers who participated in the in-service teacher training on integrated science, and the responses of 384 high school science teachers were analyzed. According to the results of the survey, integrated science was allotted six units to each school, and two or more teachers divided achievement standards and were responsible for them in many cases. Science teachers pointed to the increase of student-oriented activities as the biggest change due to the application of integrated science and also showed a positive attitude towards increasing the proportion of performance-based assessment, diversifying evaluation methods, increasing teacher consultations, and enhancing the holistic understanding of natural phenomenon, etc. In particular, teachers with 15 years or more of teaching experience were significantly positive about the increase of student-oriented activities, diverse assessment methods, and opportunities of teacher consultations. For teachers with a sub-major in science, teaching about non-majored contents was the most difficult and it was also difficult to determine the appropriate level of contents to teach. Teachers who majored common science, however, rarely complained about teaching non-majored content. In the case of two teachers in charge of integrated science, there was a statistically significant demand for subject matter knowledge as training content, and for mixed education incorporating theory and practice and customized training as a training method. In the case of one teacher responsible for the subject, there was a relatively lower demand. From these results, some implications for the successful implementation of integrated science were discussed.

A Structural Equation Modeling of Internalizing Problem Behaviors of Korean Chinese'left-behind'Children in China (중국 조선족 유수아동의 내재화 문제행동에 관한 구조모형)

  • Hyun, Mina;Park, Jisun;Shin, Dong-Myeon
    • 한국사회정책
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    • v.24 no.1
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    • pp.153-185
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    • 2017
  • The purpose of this study is to investigate the actual conditions and causes of the problem behaviors of Korean Chinese'left-behind'children in China in order to propose a support system to prevent problem behaviors of them. For this purpose, a questionnaire survey was conducted on 399 children who attend at three Korean Chines schools in Yonbian in China. The questionnaire consisted of general characteristics, internalizing problem behavior, social support, self-esteem, and self-resilience. This paper analysed the survey data by employing one-way ANOVA and a structural equation modeling. It verified if there is significant difference in internalizing problem behaviour, self-esteem, self-resilience, and social support between left-behind children's group and non left-behind children's group. It also identified a structural causal relationship and direct or indirect effects among problematic behaviour, self-esteem, self-resilience, and social support. The results of the analysis are as follows. First, there was a statistically significant difference in the social withdrawal and depression of internalizing problem behaviors between left-behind children's group and non left-behind children's group. Second, the left-behind children's group showed no significant difference in self-resilience and social support compared to non left-behind children's group, but showed a significant difference in self-esteem. In the positive self- esteem factor, non left-behind children's group showed much higher score whereas left-behind children's group was higher in the negative self-esteem factor. Third, social support for left-behind children's group has a statistically significant direct negative effect on internalizing problem behaviors, and indirectly negative effects on problem behavior through self-resilience. These results suggest the necessity of establishing a social support system for mitigating and preventing problem behaviors and the necessity of preparing measures to improve self-resilience. Based on the results of the study, we discussed how to establish a social support system in China to mitigate internalizing problem behaviors of Korean Chinese left-behind children.

The Leadership in Korean Confucianism and its Modern Characteristics : Chíjìng(持敬) to Zhìzhì(至治), the Leadership Wisdom (한국 유학의 리더십과 그 현대적 특징 - 지경(持敬)에서 지치(至治)로, 지혜의 리더십 -)

  • Kim, Dong-Min
    • The Journal of Korean Philosophical History
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    • no.23
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    • pp.7-65
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    • 2008
  • The object of this essay is to apply the Leadership Theory, current interest in Asian Philosophy, to Korean appliance. This is to associate contemporary Leadership Theory with Chosun Confucianism in order to discover the Korean Leadership Prototype, and seek the possibility of applying it for modern usage. The essay uses two analysis models. The tools used for the methodology consists of the personal characteristics of the leader as one axis and ruling out the roles in order to develop the discussion as the other axis. First axis is the process of the leader setting the identity and strengthening the ability to successfully deploy his/her leadership. The second axis is comprised of four specific fields where the leadership is deployed. The four sectors are Self Sector, Relationship Sector, Team Sector and Community Sector. Core values of each sector have been set up and specific competences have been presented. In the Self Sector, $zh{\grave{i}}x{\bar{i}}n$(治心) and $ch{\acute{i}}j{\grave{i}}ng$(持敬) have been set as core values and $l{\grave{i}}zh{\grave{i}}$(立志) and $sh{\acute{i}}x{\bar{i}}n$(實心) as their competences. In the Relationship Sector and Team Sector, circumstances(時宜) and $sh{\acute{i}}sh{\grave{i}}g{\bar{e}}ngzh{\bar{a}}ng$(實事更張) were set as core values, accordingly. Lastly for the Community sector, the core value, 'Ideal Leader and the Visions of and Ideal Community', was conceptualized as '$m{\grave{ui}}m{\acute{i}}nzh{\grave{i}}zh{\grave{i}}$(牧民至治)'. The leadership is then expanded from the Self Sector to the final stage through its processes. Through this research, it can be found out that the Korean Leadership Model is not rigid to just cover a specific point in time or situation, but embraces many contemporary leadership concepts, thus having the characteristics of a comprehensive leadership theory.

Analysis the Appropriate Schedule for the Installment Payment Amount and Establishment of the Post sale System and Policy in the Apartment Construction (공동주택 건설사업에서 후분양의 제도 및 정책 수립을 위한 분담금 납부 적정시기 분석)

  • Yoon, Inhwan;Bae, Byungyun
    • Korean Journal of Construction Engineering and Management
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    • v.22 no.4
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    • pp.59-65
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    • 2021
  • Since the 2016 "Housing Act Partial Amendment" and the "2018 Housing Comprehensive Amendment Plan", interest in the pre sale system and post sale system of apartment houses has been on the rise. In order to compare the advantages and disadvantages of the pre sale system and the post sale system of apartment houses, and to establish the basis for the institutional policy of the post sale system, a questionnaire survey method was used for tenants of the apartment house from the public side, and issues of time and cost. The time series analysis method is intended to suggest an appropriate time for payment of contributions. Accordingly, through a review of existing theories and literature, the post sale system of public and private institutions was organized, and through a questionnaire survey, the path to securing pre sale money, product information of the model house, and the degree of awareness of the effect of the post sale system were investigated. For the post sale fund support and payment method, it is necessary to increase the commercial line for existing financiers from the user's point of view, and it is necessary to operate in consideration of the economic power of the pre sale market by region. Both 60% post sale and 80% post sale have a price range of up to KRW 10 million, and the total interest rate is 5.0%, and the annual interest rate is about 2.8% for 60% post sale, and about 2.1% for 80% post sale, which is lower than the current 3.1%. I need an interest rate. The research is a perception survey targeting a total of 5,213 households in a sample of after sale apartments in public institutions. As the actual values are analyzed using a time series on the effects of market supply and demand and market prices, there is a limit to applying them to prospective residents of private apartments. In addition, to respond to first time tenants, a questionnaire survey was conducted on five complexes that have moved in within the last five years.

A Study Covering the Comparative Analysis of Educational Systems in Major Countries for Regular Cybersecurity Education (사이버보안 정규교육화를 위한 주요국 교육체계 비교분석 연구)

  • YOO, Jiyeon
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.1
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    • pp.397-405
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    • 2021
  • With the recent phenomenon of the Intelligence Information Society, the cyber security paradigm has begun to change. In particular, the increase of the interconnectedness of the hyperlinked society has extended the scope of damage that can be caused by cyber threats to the real world. In addition to that, it can also be a risk to any given individual who could accompany a crisis that has to do with public safety or national security. Adolescents who are digital natives are more likely to be exposed to cyber threats, which is mainly due to the fact that they are significantly more involved in cyber activities and they also possess insufficient security comprehension and safety awareness. Therefore, it is necessary to strengthen cyber security capabilities of every young individual, so that they can effectively protect themselves against cyber threats and better manage their cyber activities. It examines the changes of the security paradigm and the necessity for cyber security education, which is in direct accordance to the characteristics of a connected society that further suggests directions and a basic system of cyber security education, through a detailed analysis of the current state of Domestic and Overseas Cyber Security Education. The purpose of this study was to define cybersecurity competencies that are necessary within an intelligent information society, and to propose a regular curriculum for strengthening cybersecurity competencies, through the comparison and meticulous analysis of both domestic and overseas educational systems that are pertinent to cybersecurity competencies. Accordingly, a cybersecurity competency system was constructed, by reflecting C3-Matrix, which is a cyber competency system model of digital citizens. The cybersecurity competency system consists of cyber ethics awareness, cyber ethics behavior, cyber security and cyber safety. In addition to this, based on the basic framework of the cybersecurity competency system, the relevant education that is currently being implemented in the United States, Australia, Japan and Korea were all compared and analyzed. From the insight gained through the analysis, the domestic curriculum was finally presented. The main objective of this new unified understanding, was to create a comprehensive and effective cyber security competency curriculum.

A Machine Learning-based Total Production Time Prediction Method for Customized-Manufacturing Companies (주문생산 기업을 위한 기계학습 기반 총생산시간 예측 기법)

  • Park, Do-Myung;Choi, HyungRim;Park, Byung-Kwon
    • Journal of Intelligence and Information Systems
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    • v.27 no.1
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    • pp.177-190
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    • 2021
  • Due to the development of the fourth industrial revolution technology, efforts are being made to improve areas that humans cannot handle by utilizing artificial intelligence techniques such as machine learning. Although on-demand production companies also want to reduce corporate risks such as delays in delivery by predicting total production time for orders, they are having difficulty predicting this because the total production time is all different for each order. The Theory of Constraints (TOC) theory was developed to find the least efficient areas to increase order throughput and reduce order total cost, but failed to provide a forecast of total production time. Order production varies from order to order due to various customer needs, so the total production time of individual orders can be measured postmortem, but it is difficult to predict in advance. The total measured production time of existing orders is also different, which has limitations that cannot be used as standard time. As a result, experienced managers rely on persimmons rather than on the use of the system, while inexperienced managers use simple management indicators (e.g., 60 days total production time for raw materials, 90 days total production time for steel plates, etc.). Too fast work instructions based on imperfections or indicators cause congestion, which leads to productivity degradation, and too late leads to increased production costs or failure to meet delivery dates due to emergency processing. Failure to meet the deadline will result in compensation for delayed compensation or adversely affect business and collection sectors. In this study, to address these problems, an entity that operates an order production system seeks to find a machine learning model that estimates the total production time of new orders. It uses orders, production, and process performance for materials used for machine learning. We compared and analyzed OLS, GLM Gamma, Extra Trees, and Random Forest algorithms as the best algorithms for estimating total production time and present the results.

Extract of Fructus Corni Ameliorates Testosterone-induced Benign Prostatic Hypertrophy in Sprague Dawley Rats (산수유 추출물에 의한 testosterone으로 유발된 양성 전립선 비대증의 개선)

  • Ji, Seon Yeong;Kim, Min Yeong;Hwangbo, Hyun;Lee, Hyesook;Hong, Su Hyun;Kim, Tae Hee;Yoon, Seonhye;Kim, Hyun Jin;Jung, Ha Eun;Kim, Sung Yeon;Kim, Tae Jung;Kim, Min Ji;Kim, Sung Ok;Choi, Yung Hyun
    • Journal of Life Science
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    • v.31 no.6
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    • pp.550-558
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    • 2021
  • Fructus Corni, the fruit of Cornus officinalis, has long been used for the prevention and treatment of various diseases. We recently suggested that it was effective against benign prostatic hyperplasia (BPH). In this study, we investigated the inhibitory effect of Corni Fructus (CF) water extract on BPH induced by testosterone propionate (TP) in noncastrated and castrated animal models. BPH was induced in Sprague Dawley rats by an intramuscular injection of TP in castrated or noncastrated rats. Finasteride (FINA) treatment was used as a positive control for inhibition of BPH. According to our results, CF administration inhibited excessive enlargement of development of the prostate in both the noncastrated and castrated groups compared to the control and FINA-treated groups. The inhibitory effect of CF on BPH was associated with inhibition of expression of hypoxia-inducible factor-1α, 5α-reductase type 2, steroid receptor coactivator-1, androgen receptor (AR), and prostate-specific antigen. Serum levels of the stress hormone cortisol increased during BPH induction by TP in both the noncastrated and castrated groups, but they were attenuated significantly by CF administration. However, insulin and IGF-1 levels were not increased in the BPH-induced groups and CF, and no effective results were found by CF administration. These results point to a beneficial effect of CF on BPH through inhibition of AR signaling pathway activity and imply that CF shows excellent potential as a therapeutic agent for the prevention and treatment of BPH.

The effect of reduced thickness in different regions on the fracture resistance of monolithic zirconia crowns (다양한 부위에서의 감소된 두께가 지르코니아 크라운의 파절 저항에 미치는 영향)

  • Abukabbos, Layla;Park, Je Uk;Lee, Wonsup
    • The Journal of Korean Academy of Prosthodontics
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    • v.60 no.2
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    • pp.135-142
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    • 2022
  • Purpose. This study aims to evaluate the combined effect of reduced thickness in different regions on the fracture resistance of monolithic zirconia crowns. Materials and methods. Seven nickel-chromium dies were generated from a 3D model of mandibular first molar using the digital scanner with the following geometries: 1.5 mm occlusal reduction, 1.0 mm deep chamfer. Based on the abutment model, Zirconia blocks (Luxen Zirconia) were selected to fabricate Sixty-three zirconia crowns with occlusal thicknesses of 0.3 mm, 0.5 mm, and 1.5 mm, and different axial thicknesses of 0.3 mm, 0.5 mm, and 1.0 mm. All crowns were cemented by resin cement. Next, the crowns were subjected to load-to-fracture test until fracture using an electronic universal testing machine. In addition, fracture patterns were observed with a scanning electron microscope (SEM). Two-way ANOVA and the Tuckey HSD test for post hoc analysis were used for statistical analysis (P < .05). Results. The mean values of fracture resistancerecorded was higher than the average biting force in the posterior region. The two-way ANOVA showed that the occlusal and axial thickness affected the fracture resistance significantly (P < .05). However, the effect of axial thickness on fracture resistance did not show a statistical difference when thicker than 0.5 mm. The observed failure modes were partial or complete fracture depending on the severity of crack propagation. Conclusion. Within the limitations of the present study, the CAD-CAM monolithic zirconia crown with extremely reduced thickness showed adequate fracture resistance to withstand occlusal load in molar regions. In addition, both occlusal and axial thickness affected the fracture resistance of the zirconia crown and showed different results as combined.

Research on the Measures and Driving Force behind the Three Major Works of Daesoon Jinrihoe in North Korea in Case of the Respective Types of Unification on the Korean Peninsula (한반도 통일 유형별 북한지역의 대순진리회 3대 중요사업 추진 여건과 방안 연구)

  • Park, Young-taek
    • Journal of the Daesoon Academy of Sciences
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    • v.39
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    • pp.137-174
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    • 2021
  • The main theme of this paper centers on how to promote Three Major Works of Daesoon Jinrihoe, charity aid, social welfare, and education projects, during the unification period. Determining the best methods of promotion is crucial because the Three Major Works must be carried out after unification, and the works must remain based on the practice of the philosophy of Haewon-sangsaeng (the Resolution of Grievances for Mutual Beneficence). The idea of Haewon-sangsaeng is in line with the preface of the U.N. Charter and the aim of world peace. North Korean residents are suffering from starvation under their devastated economy, which is certain to face a crisis of materialistic deficiency during reunification. In this study, the peaceful unification of Germany, unification under a period of sudden changes in Yemen, and the militarized unification of Vietnam were taken as case studies to diagnose and analyze the conditions which would affect the implementation of the Three Major Works. These three styles of unification commonly required a considerable budget and other forms of support to carry out the Three Major Works. Especially if unification were to occur after a period of sudden changes, this would require solutions to issues of food, shelter, and medical support due to the loss of numerous lives and the destruction of infrastructure. On the other hand, the UNHCR model was analyzed to determine the implications of expanding mental well prepared and sufficiently qualified professionals, reorganizing standard organizations within complex situations, task direction, preparing sufficient relief goods, budgeting, securing bases in border areas with North Korea, and establishing networks for sponsorship. Based on this, eight detailed tasks in the field of system construction could be used by the operators of the Three Major Works to prepare for unification. Additionally, nine tasks for review were presented in consideration of the timing of unification and the current situation between South and North Korea. In conclusion, in the event of unification, the Three Major Works should not be neglected during the transition period. The manual "Three Major Works during the Unification Period" should include strategic points on organizational formation and mission implementation, forward base and base operation, security and logistics preparation, public relations and external cooperation, safety measures, and transportation and contact systems.