• Title/Summary/Keyword: Performance Issues

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Analysis of Drone Downwash and Droplet Deposition for Improved Aerial Spraying Efficiency in Agriculture (드론 방제 살포 효율 개선을 위한 하향풍 및 액적 퇴적 분포 분석)

  • Lee, Se-Yeon;Park, Jinseon;Lee, Chae-Rin;Choi, Lak-Yeong;Daniel Kehinde Favour;Park, Ji-Yeon;Hong, Se-Woon
    • Journal of The Korean Society of Agricultural Engineers
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    • v.66 no.5
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    • pp.51-65
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    • 2024
  • With the advancement of Unmanned Aerial Vehicles (UAV) technology, aerial spraying has been rapidly increasing in the agricultural field. Drones offer many advantages compared to traditional applicators, but they pose challenges such as spray drift risk and spray uniformity. To address these issues, it is essential to understand the characteristics of complex airflow generated by drones and its consequences for the spray performance. This study aims to identify the air velocity distribution of drone downwash and the resulting spray deposition distribution on the ground, ultimately proposing optimized spraying widths and criteria. Experiments were conducted using two agricultural drones with different propeller arrangements under various flight and measurement conditions. The results showed that during hovering, the downward airflow affected the area within a distance of the radius of the blade (R) from the center of the drone. When the drone was flying, the downward airflow was effective up to a distance of 2R. Droplet deposition was concentrated at the center of the drone during hovering. However, during flying, the droplet deposition was more evenly distributed up to the distance of R. The drone downwash and droplet deposition were significantly different during flying compared to the hovering state. At an effective spray width of 3R, the coefficient of variation (CV) was generally less than 16%, indicating a significant improvement in spray uniformity. These findings help optimize effective spraying techniques in drone-based applications.

Investigating Dynamic Mutation Process of Issues Using Unstructured Text Analysis (부도예측을 위한 KNN 앙상블 모형의 동시 최적화)

  • Min, Sung-Hwan
    • Journal of Intelligence and Information Systems
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    • v.22 no.1
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    • pp.139-157
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    • 2016
  • Bankruptcy involves considerable costs, so it can have significant effects on a country's economy. Thus, bankruptcy prediction is an important issue. Over the past several decades, many researchers have addressed topics associated with bankruptcy prediction. Early research on bankruptcy prediction employed conventional statistical methods such as univariate analysis, discriminant analysis, multiple regression, and logistic regression. Later on, many studies began utilizing artificial intelligence techniques such as inductive learning, neural networks, and case-based reasoning. Currently, ensemble models are being utilized to enhance the accuracy of bankruptcy prediction. Ensemble classification involves combining multiple classifiers to obtain more accurate predictions than those obtained using individual models. Ensemble learning techniques are known to be very useful for improving the generalization ability of the classifier. Base classifiers in the ensemble must be as accurate and diverse as possible in order to enhance the generalization ability of an ensemble model. Commonly used methods for constructing ensemble classifiers include bagging, boosting, and random subspace. The random subspace method selects a random feature subset for each classifier from the original feature space to diversify the base classifiers of an ensemble. Each ensemble member is trained by a randomly chosen feature subspace from the original feature set, and predictions from each ensemble member are combined by an aggregation method. The k-nearest neighbors (KNN) classifier is robust with respect to variations in the dataset but is very sensitive to changes in the feature space. For this reason, KNN is a good classifier for the random subspace method. The KNN random subspace ensemble model has been shown to be very effective for improving an individual KNN model. The k parameter of KNN base classifiers and selected feature subsets for base classifiers play an important role in determining the performance of the KNN ensemble model. However, few studies have focused on optimizing the k parameter and feature subsets of base classifiers in the ensemble. This study proposed a new ensemble method that improves upon the performance KNN ensemble model by optimizing both k parameters and feature subsets of base classifiers. A genetic algorithm was used to optimize the KNN ensemble model and improve the prediction accuracy of the ensemble model. The proposed model was applied to a bankruptcy prediction problem by using a real dataset from Korean companies. The research data included 1800 externally non-audited firms that filed for bankruptcy (900 cases) or non-bankruptcy (900 cases). Initially, the dataset consisted of 134 financial ratios. Prior to the experiments, 75 financial ratios were selected based on an independent sample t-test of each financial ratio as an input variable and bankruptcy or non-bankruptcy as an output variable. Of these, 24 financial ratios were selected by using a logistic regression backward feature selection method. The complete dataset was separated into two parts: training and validation. The training dataset was further divided into two portions: one for the training model and the other to avoid overfitting. The prediction accuracy against this dataset was used to determine the fitness value in order to avoid overfitting. The validation dataset was used to evaluate the effectiveness of the final model. A 10-fold cross-validation was implemented to compare the performances of the proposed model and other models. To evaluate the effectiveness of the proposed model, the classification accuracy of the proposed model was compared with that of other models. The Q-statistic values and average classification accuracies of base classifiers were investigated. The experimental results showed that the proposed model outperformed other models, such as the single model and random subspace ensemble model.

Derivation and Empirical Analysis of Critical Factors that Facilitate Technology Transfer and Commercialization of Research Outcome (연구성과의 기술이전 및 사업화 촉진요인 도출 및 실증분석)

  • Ku, Bon Chul
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.9 no.5
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    • pp.69-81
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    • 2014
  • There is a growing interest in the technology transfer and commercialization both at home and abroad. Accordingly, this study looked at the concept of technology transfer and commercialization, identified the factors that should be taken into account in order to facilitate technology transfer and commercialization, and then performed a empirical analysis. As for the conventional technology transfer and commercialization, there was a tendency to limit its scope to the exploration, transfer and commercialization of technology itself. Here in this research, technology transfer and commercialization is defined the category to expand as various activities implemented in order to make sure that intellectual properties such as intangible technological developments, know-how, and knowledge are transferred between the relevant parties through a contract or negotiation, and the party to which the transfer is made can then further develop and exploit the technology into tangible products and other activities to obtain economic benefit out of that. In addition, the findings of the positive analysis of technology transfer and commercialization revealed that the focus of facilitating technology transfer has been on the technology itself, its management and securing efficiency of the systems and institutions involved in the technology transfer and commercialization. So there was lack of recognition as to the importance of financial support given to the phase of technology commercialization. This indicates that when it comes to the technology transfer and commercialization, quantitative performance has been the focus of interest such as patent application, registration, number of technology transfers, royalty, etc. So there was not enough understanding as to the issues of starting up a business, creating quality jobs through technology transfer and commercialization, which are directly related to the realization of the creative economy. In this regard, this research is expected to be used for the development for the future policies to boost technology transfer and commercialization as it suggests not only simply ensuring quantitative performance but also necessary to create the environment for the creation of the stable ecosystem for the parties involved in the technology transfer and commercialization and then to build circumstances in which creative economy can be realized.

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An investigation of the User Research Techniques in the User-Centered Design Framework - Focused on the on-line community services development for 13-18 Young Adults (사용자 중심 디자인 프레임워크에서 사용자 조사기법의 역할에 관한 연구 - 13-18 청소년용 온라인 커뮤니티 컨텐트 개발 프로젝트를 중심으로)

  • 이종호
    • Archives of design research
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    • v.17 no.2
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    • pp.77-86
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    • 2004
  • User-Centered Design Approach plays important role in dealing with usability issues for developing modern technology products. Yet it is still questionable whether the User-Centered approach is enough for the development of successful consumer contents since the User-Centered Design is originated from the software engineering field where meeting customers' functional requirement is the most critical aspect in developing a software. However, modern consumer market is already saturated and in order to meet ever increasing consumer requirements, the User-Centered Design approach needs to be expanded. As a way of incorporating the User-Centered Approach into the consumer product development, Jordan suggested the 'Pleasure-based Approach' in industrial design field, which usually generates multi-dimensional user requirements: 1)physical, 2)cognitive, 3)identity and 4) social. It is the current tendency that many portal and community service providers focus on fulfilling both functional and emotional needs for users when developing new items, contents and services. Previously fulfilling consumers' emotional needs solely depend on visual designer's graphical sense and capability. However, taking the customer-centered approach on withdrawing consumers' unknown needs is getting critical in the competitive market environment. This paper reviews different types of user research techniques and categorized into 6 ways based on Kano(1992)'s product quality model. Based on his theory, only performance factors, such as suability, can be identified through the user-centered design approach. The user-centered design approach has to be expanded to include factors include personality, sociability, pleasure, and so on. In order to identify performance as well as excellent factors through user research, a user-research framework was established and tested through the case study, which is ' the development of new online service for teens '. The results of the user research were summarized at the end of the paper and the pros and cons of each research techniques were analyzed.

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Effects of Patriotism on Product Evaluation: Focused on the Mediating Effects of Consumer Ethnocentrism (애국심이 제품평가에 미치는 영향: 소비자 자민족중심주의의 매개효과를 중심으로)

  • Hong, Sung-Tai;Kang, Dong-Kyoon
    • Journal of Distribution Research
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    • v.15 no.2
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    • pp.71-99
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    • 2010
  • Most of studies on patriotism in the marketing area have focused on ethnocentric tendencies observed in consumption behaviors. On the contrary, there have been few empirical studies on how patriotism in the general sense, indicating affection for, attachment to, and pride in the country, influences consumers' evaluation of domestic and foreign products. Given the current situation that marketing activities appealing to people's patriotism is increasing, this is somewhat surprising. Thus, this study examined empirically how patriotism influences people's evaluation of domestic and foreign products. In addition, we tested whether consumer ethnocentrism works as an intervening variable in the relation between patriotism and product evaluation. The empirical analysis was conducted through a questionnaire survey of undergraduate and graduate students at universities in Seoul. The survey asked about the respondents' patriotism, consumer ethnocentrism, domestic product evaluation, foreign product evaluation, and demographical characteristics. In foreign product evaluation, the respondents were requested to evaluate Chinese and Japanese products. Email was used to send and recover the questionnaires, and 135 replies were used in the analysis. Major findings from the empirical analysis are as follows. First, a significant relationship was observed between patriotism and domestic product evaluation. That is, patriotic participants evaluated domestic products more favorably. On the other hand, no significant relationship was observed between patriotism and foreign product evaluation(See Table 1-1 and 1-2). Next, the effect of patriotism on domestic product evaluation was mediated by consumer ethnocentrism. However, whether the effect of patriotism on domestic product evaluation is mediated by consumer ethnocentrism partially or fully was different according to product(See Table 2-1 and 2-2). Lastly, we tried to analyze the relation between consumer ethnocentrism and product evaluation and comparing the results with findings of previous researches. According to the results, a significant relationship was observed between consumer ethnocentrism and domestic product evaluation but not between consumer ethnocentrism and foreign product evaluation. The meanings of this study are as follows. First, there have been few marketing studies that investigated the relation between patriotism and product evaluation. Thus, this study is meaningful in that it supplemented the limitation of previous research. Second, consumer ethnocentrism was found to mediate the relation between patriotism and domestic product evaluation. Considering the absence of previous research that examined the role of consumer ethnocentrism as an intervening variable, this study is significant in that it expanded the scope of research on consumer ethnocentrism. Third, from the practical aspect, the results of this study suggest that marketing appealing to patriotism is effective in stimulating consumers' purchase and consumption of domestic products. Accordingly, such a marketing strategy is expected to be effective in protecting domestic markets from imported goods and overseas brands and to increase demands for domestic products and brands. However, there is the question of whether the effect of patriotism based marketing strategies in promoting demand for domestic products would persist. That is, this study could not find a significant relation between patriotism and foreign product evaluation, and this means that the increase in patriotism for the home country does not damage people's view to the quality of foreign products negatively. Accordingly, without change in people's perception of foreign products, it is highly likely that the increase in demand for domestic products or brands induced by patriotism elevated at a specific time or situation may not last long. Fourth, the results of this study suggest that the patriotism level may influence consumers' choice behavior toward retailers strongly connected to a specific country or region. That is, consumers with high level patriotism may hesitate or avoid using a retailer associated with some foreign country. Fifth, according to the results of this study, when people's patriotism is stimulated by a specific social situation or event, it can be an opportunity for domestic franchise brands to increase their market performance such as sales and market share and, at the same time, for foreign franchise brands to experience adversities. Therefore, during a period like the Olympic Games or the World Cup when people's sense of belonging or attachment to their country is heightened, domestic franchise brands need to make marketing activities that may lead market opportunities to substantial results and foreign franchise brands to cope with such adversities. Sixth, consumers' brand choice is often made in retail stores. It has been demonstrated by numerous studies that in store stimuli such as point of purchase display can affect consumers' behavior. Considering this, domestic brands facing competition with foreign brands should make continuous efforts to enhance the market performance of their products through developing in store stimuli that can stimulate consumers' patriotism. Finally, based on the major findings of this study, both academic and practical issues were discussed. Suggestions for future studies were provided.

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Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2010 (설비공학 분야의 최근 연구 동향 : 2010년 학회지 논문에 대한 종합적 고찰)

  • Han, Hwa-Taik;Lee, Dae-Young;Kim, Seo-Young;Choi, Jong-Min;Kim, Su-Min;Kwon, Young-Chul;Baik, Yong-Kyu
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.23 no.6
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    • pp.449-469
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    • 2011
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering during 2010. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery, and new and renewable energy. Various topics were presented in the field of general thermal and fluid flow. Research issues mainly focused on the thermal reliability of axial fan and compressor in the field of fluid machinery. Studies on the design of ground source heat pump systems and solar chemical reactors were executed in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (3) Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and CO2 were studied. Performance improvement of refrigeration systems are tried applying various ideas of refrigerant subcooling, dual evaporator with hot gas bypass control and feedforward control. The hybrid solar systems combining the solar collection devices with absorption chillers or compression heat pumps are simulated and studied experimentally as well to improve the understanding and the feasibility for actual applications. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. Various studies on heating and cooling systems, HVAC facilities, indoor air environments and energy resources were carried to improve the maintenance and management of building service equipments. In the field of heating and cooling systems, papers on a transformer cooling system, a combined heat and power, a slab thermal storage and a heat pump were reported. In the field of HVAC facilities, papers on a cooling load, an ondol and a drying were presented. Also, studies on HVAC systems using unutilized indoor air environments and energy resources such as air curtains, bioviolence, cleanrooms, ventilation, district heating, landfill gas were studied. (5) In the field of architectural environment and energy, studies of various purposes were conducted such as indoor environment, building energy, renewable energy and green building. In particular, renewable energy and building energy-related researches have mainly been studied reflecting the global interest. In addition, many researches which related the domestic green building certification of school building were performed to improve the indoor environment of school.

Usefulness of Dental Hygiene Education Curriculum in the Public Oral Health Service Performance in Korea (한국의 보건소 근무 치과위생사의 공중구강보건사업 수행업무실태와 대학교육간의 연관성)

  • Yoo, Ja-Hea;Cho, Young-Sik;Chung, Won-Gyun;Kwon, Ho-Keun
    • Journal of dental hygiene science
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    • v.5 no.4
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    • pp.165-170
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    • 2005
  • The purpose of this study was to evaluate the usefulness of dental hygiene education curriculum such as oral prophylaxis, preventive dentistry, public oral health, oral health statistics, oral health education in the public oral health service performance. Questionnaire survey was posed to 96 dental hygienists working in health centers and health sub-centers. The relativity among frequency of task, usefulness, importance, and reinforcement of the education curriculum in the health centers, and the effect of current dental hygiene education curriculum on public oral health service were studied. The results were follows; 1. Sealant was performed the most frequently in the health centers and health sub-centers, and it was also the most useful content in the education curriculum. And the tooth brushing method was considered the most important in the curriculum. Therefore, oral health education was considered as factor which required the most reinforcement. However, the issues of school water fluoridation and water fluoridation in the public oral health were barely brought up as a matter of subject. 2. In the relationship between the frequency of task and the usefulness of curriculum, it showed that the more frequency of task was more useful. In the relationship between importance and reinforcements of curriculum, it showed that the more importance of the education curriculum requires more reinforcement. And more frequently performed task should be more strengthened. 3. According to the education course hours, current education curriculum course hours were 532.4 hours, which is 42.9 hours more spent than the original curriculum guideline. Lecture hours were 205.4 hours, which is 50.6 hours less, and the practice hours were 327 hours, which is 93.5 hours more than the original curriculum guideline. 4. Because of the insufficient course hours of curriculum compared to the frequency of the task, the oral health education, oral prophylaxis, and preventive dentistry should be reinforced more than now. But the oral health statistics and public oral health curriculum were not only emphasized, but also any reinforced compared to other tasks.

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Development of Korean Green Business/IT Strategies Based on Priority Analysis (한국의 그린 비즈니스/IT 실태분석을 통한 추진전략 우선순위 도출에 관한 연구)

  • Kim, Jae-Kyeong;Choi, Ju-Choel;Choi, Il-Young
    • Asia pacific journal of information systems
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    • v.20 no.3
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    • pp.191-204
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    • 2010
  • Recently, the CO2 emission and energy consumption have become critical global issues to decide the future of nations. Especially, the spread of IT products and the increased use of internet and web applications result in the energy consumption and CO2 emission of IT industry though information technologies drive global economic growth. EU, the United States, Japan and other developed countries are using IT related environmental regulations such as WEEE(Waste Electrical and Electronic Equipment), RoHS(Restriction of the use of Certain Hazardous Substance), REACH(Registration, Evaluation, Authorization and Restriction of CHemicals) and EuP(Energy using Product), and have established systematic green business/IT strategies to enhance the competitiveness of IT industry. For example, the Japan government proposed the "Green IT initiative" for being compatible with economic growth and environmental protection. Not only energy saving technologies but energy saving systems have been developed for accomplishing sustainable development. Korea's CO2 emission and energy consumption continuously have grown at comparatively high rates. They are related to its industrial structure depending on high energy-consuming industries such as iron and steel Industry, automotive industry, shipbuilding industry, semiconductor industry, and so on. In particular, export proportion of IT manufacturing is quite high in Korea. For example, the global market share of the semiconductor such as DRAM was about 80% in 2008. Accordingly, Korea needs to establish a systematic strategy to respond to the global environmental regulations and to maintain competitiveness in the IT industry. However, green competitiveness of Korea ranked 11th among 15 major countries and R&D budget for green technology is not large enough to develop energy-saving technologies for infrastructure and value chain of low-carbon society though that grows at high rates. Moreover, there are no concrete action plans in Korea. This research aims to deduce the priorities of the Korean green business/IT strategies to use multi attribute weighted average method. We selected a panel of 19 experts who work at the green business related firms such as HP, IBM, Fujitsu and so on, and selected six assessment indices such as the urgency of the technology development, the technology gap between Korea and the developed countries, the effect of import substitution, the spillover effect of technology, the market growth, and the export potential of the package or stand-alone products by existing literature review. We submitted questionnaires at approximately weekly intervals to them for priorities of the green business/IT strategies. The strategies broadly classify as follows. The first strategy which consists of the green business/IT policy and standardization, process and performance management and IT industry and legislative alignment relates to government's role in the green economy. The second strategy relates to IT to support environment sustainability such as the travel and ways of working management, printer output and recycling, intelligent building, printer rationalization and collaboration and connectivity. The last strategy relates to green IT systems, services and usage such as the data center consolidation and energy management, hardware recycle decommission, server and storage virtualization, device power management, and service supplier management. All the questionnaires were assessed via a five-point Likert scale ranging from "very little" to "very large." Our findings show that the IT to support environment sustainability is prior to the other strategies. In detail, the green business /IT policy and standardization is the most important in the government's role. The strategies of intelligent building and the travel and ways of working management are prior to the others for supporting environment sustainability. Finally, the strategies for the data center consolidation and energy management and server and storage virtualization have the huge influence for green IT systems, services and usage This research results the following implications. The amount of energy consumption and CO2 emissions of IT equipment including electrical business equipment will need to be clearly indicated in order to manage the effect of green business/IT strategy. And it is necessary to develop tools that measure the performance of green business/IT by each step. Additionally, intelligent building could grow up in energy-saving, growth of low carbon and related industries together. It is necessary to expand the affect of virtualization though adjusting and controlling the relationship between the management teams.

Improving Work Adjustment Skills in Students with Mental Retardation Using Hydroponics Program (수경재배 프로그램을 통한 지적 장애학생의 직업적응력 증진)

  • Joo, Byung-Sik;Park, Sin-Ae;Son, Ki-Cheol
    • Horticultural Science & Technology
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    • v.30 no.5
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    • pp.586-595
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    • 2012
  • This study was conducted to determine the effects of horticultural therapy (HT) program using hydroponics on work adjustment skills of students with mental retardation. Based on the critical role transitional model and special education curriculum for agriculture, especially hydroponics, HT program (total 22 sessions) using hydroponics procedure for Lettuce (Lactuca sativa L. 'Asia Heuk Romaine') was developed. Fourteen (10 males, 4 females) graded $1^{st}$ to $2^{nd}$ with intellectual disabilities were recruited from a special education class in a high school located in Inchon, Korea and then a special farm for hydroponics in Inchon, Korea was offered for the HT program. The students with intellectual disabilities participated in the HT program for 4-month (from September to December of 2011, twice a week, approximately 60 minutes per session). Before and after the HT program, the McCarron assessment neuromuscular development, emotional behavioral checklist, interpersonal negotiation strategies, and KEPAD picture vocational interest test were performed by the teachers and horticultural therapists. As the results, the students significantly improved motor performance (p = 0.002), emotional behavioral strategies (p = 0.00), and interpersonal negotiation strategies (p = 0.05). However, no significant difference between before and after the HT program for vocational interest was observed. In conclusion, the HT program using hydroponics, consists of simple and easy tasks so that it would be applicable for the students with intellectual disabilities positively affected to work adjustment skills by improving the motor performance, emotional behavioral strategies, and interpersonal negotiation strategies. Additionally, HT programs using hydroponics with various kinds of vegetables are required to develop and to apply in practical settings for improving work adjustment skills.

New Approaches for Overcoming Current Issues of Plasma Sputtering Process During Organic-electronics Device Fabrication: Plasma Damage Free and Room Temperature Process for High Quality Metal Oxide Thin Film

  • Hong, Mun-Pyo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.100-101
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    • 2012
  • The plasma damage free and room temperature processedthin film deposition technology is essential for realization of various next generation organic microelectronic devices such as flexible AMOLED display, flexible OLED lighting, and organic photovoltaic cells because characteristics of fragile organic materials in the plasma process and low glass transition temperatures (Tg) of polymer substrate. In case of directly deposition of metal oxide thin films (including transparent conductive oxide (TCO) and amorphous oxide semiconductor (AOS)) on the organic layers, plasma damages against to the organic materials is fatal. This damage is believed to be originated mainly from high energy energetic particles during the sputtering process such as negative oxygen ions, reflected neutrals by reflection of plasma background gas at the target surface, sputtered atoms, bulk plasma ions, and secondary electrons. To solve this problem, we developed the NBAS (Neutral Beam Assisted Sputtering) process as a plasma damage free and room temperature processed sputtering technology. As a result, electro-optical properties of NBAS processed ITO thin film showed resistivity of $4.0{\times}10^{-4}{\Omega}{\cdot}m$ and high transmittance (>90% at 550 nm) with nano- crystalline structure at room temperature process. Furthermore, in the experiment result of directly deposition of TCO top anode on the inverted structure OLED cell, it is verified that NBAS TCO deposition process does not damages to the underlying organic layers. In case of deposition of transparent conductive oxide (TCO) thin film on the plastic polymer substrate, the room temperature processed sputtering coating of high quality TCO thin film is required. During the sputtering process with higher density plasma, the energetic particles contribute self supplying of activation & crystallization energy without any additional heating and post-annealing and forminga high quality TCO thin film. However, negative oxygen ions which generated from sputteringtarget surface by electron attachment are accelerated to high energy by induced cathode self-bias. Thus the high energy negative oxygen ions can lead to critical physical bombardment damages to forming oxide thin film and this effect does not recover in room temperature process without post thermal annealing. To salve the inherent limitation of plasma sputtering, we have been developed the Magnetic Field Shielded Sputtering (MFSS) process as the high quality oxide thin film deposition process at room temperature. The MFSS process is effectively eliminate or suppress the negative oxygen ions bombardment damage by the plasma limiter which composed permanent magnet array. As a result, electro-optical properties of MFSS processed ITO thin film (resistivity $3.9{\times}10^{-4}{\Omega}{\cdot}cm$, transmittance 95% at 550 nm) have approachedthose of a high temperature DC magnetron sputtering (DMS) ITO thin film were. Also, AOS (a-IGZO) TFTs fabricated by MFSS process without higher temperature post annealing showed very comparable electrical performance with those by DMS process with $400^{\circ}C$ post annealing. They are important to note that the bombardment of a negative oxygen ion which is accelerated by dc self-bias during rf sputtering could degrade the electrical performance of ITO electrodes and a-IGZO TFTs. Finally, we found that reduction of damage from the high energy negative oxygen ions bombardment drives improvement of crystalline structure in the ITO thin film and suppression of the sub-gab states in a-IGZO semiconductor thin film. For realization of organic flexible electronic devices based on plastic substrates, gas barrier coatings are required to prevent the permeation of water and oxygen because organic materials are highly susceptible to water and oxygen. In particular, high efficiency flexible AMOLEDs needs an extremely low water vapor transition rate (WVTR) of $1{\times}10^{-6}gm^{-2}day^{-1}$. The key factor in high quality inorganic gas barrier formation for achieving the very low WVTR required (under ${\sim}10^{-6}gm^{-2}day^{-1}$) is the suppression of nano-sized defect sites and gas diffusion pathways among the grain boundaries. For formation of high quality single inorganic gas barrier layer, we developed high density nano-structured Al2O3 single gas barrier layer usinga NBAS process. The NBAS process can continuously change crystalline structures from an amorphous phase to a nano- crystalline phase with various grain sizes in a single inorganic thin film. As a result, the water vapor transmission rates (WVTR) of the NBAS processed $Al_2O_3$ gas barrier film have improved order of magnitude compared with that of conventional $Al_2O_3$ layers made by the RF magnetron sputteringprocess under the same sputtering conditions; the WVTR of the NBAS processed $Al_2O_3$ gas barrier film was about $5{\times}10^{-6}g/m^2/day$ by just single layer.

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