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Performance Evaluation to Develop an Engineering Scale Cathode Processor by Multiphase Numerical Analysis (다상유동 전산모사를 통한 공학 규모의 cathode processor의 성능평가)

  • Yoo, Bung Uk;Park, Sung Bin;Kwon, Sang Woon;Kim, Jeong Guck;Lee, Han Soo;Kim, In Tae;Lee, Jong Hyeon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.12 no.1
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    • pp.7-17
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    • 2014
  • Molten salt electrorefining process achieves uranium deposits at cathode using an electrochemical processing of spent nuclear fuel. In order to recover pure uranium from cathode deposit containing about 30wt% salt, the adhered salt should be removed by cathode process (CP). The CP has been regarded as one of the bottle-neck of the pyroprocess as the large amount of uranium is treated in this step and the operation parameters are crucial to determine the final purity of the product. Currently, related research activities are mainly based on experiments consequently it is hard to observe processing variables such as temperature, pressure and salt gas behavior during the operation of the cathode process. Hence, in this study operation procedure of cathode process is numerically described by using appropriate mathematical model. The key parameters of this research are the amount of evaporation at the distillation part, diffusion coefficient of gas phase salt in cathode processor and phase change rate at condensation part. Each of these conditions were composed by Hertz-Langmuir equation, Chapman-Enskog theory, and interphase mass flow application in ANSYS-CFX. And physical properties of salt were taken from the data base in HSC Chemistry. In this study, calculation results on the salt gas behavior and optimal operating condition are discussed. The numerical analysis results could be used to closely understand the physical phenomenon during CP and for further scale up to commercial level.

Yearly Estimation of Rice Growth and Bacterial Leaf Blight Inoculation Effect Using UAV Imagery (무인비행체 영상 기반 연차 간 벼 생육 및 흰잎마름병 병해 추정)

  • Lee, KyungDo;Kim, SangMin;An, HoYong;Park, ChanWon;Hong, SukYoung;So, KyuHo;Na, SangIl
    • Journal of The Korean Society of Agricultural Engineers
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    • v.62 no.4
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    • pp.75-86
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    • 2020
  • The purpose of this study is to develop a technology for estimating rice growth and damage effect according to bacterial leaf blight using UAV multi-spectral imagery. For this purpose, we analyzed the change of aerial images, rice growth factors (plant height, dry weight, LAI) and disease effects according to disease occurrence by using UAV images for 3 rice varieties (Milyang23, Sindongjin-byeo, Saenuri-byeo) from 2017 to 2018. The correlation between vegetation index and rice growth factor during vegetative growth period showed a high value of 0.9 or higher each year. As a result of applying the growth estimation model built in 2017 to 2018, the plant height of Milyang23 showed good error withing 10%. However, it is considered that studies to improve the accuracy of other items are needed. Fixed wing unmanned aerial photographs were also possible to estimate the damage area after 2 to 4 weeks from inoculation. Although sensing data in the multi-spectral (Blue, Green, Red, NIR) band have limitations in early diagnosis of rice disease, for rice varieties such as Milyang23 and Sindongjin-byeo, it was possible to construct the equation of infected leaf area ratio and rice yield estimation using UAV imagery in early and mid-September with high correlation coefficient of 0.8 to 0.9. The results of this study are expected to be useful for farming and policy support related to estimating rice growth, rice plant disease and yield change based on UAV images.

Establishment of Inundation Probability DB for Forecasting the Farmland Inundation Risk Using Weather Forecast Data (기상예보 기반 농촌유역 침수 위험도 예보를 위한 침수 확률 DB 구축)

  • Kim, Si-Nae;Jun, Sang-Min;Lee, Hyun-Ji;Hwang, Soon-Ho;Choi, Soon-Kun;Kang, Moon-Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.62 no.4
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    • pp.33-43
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    • 2020
  • In order to reduce damage from farmland inundation caused by recent climate change, it is necessary to predict the risk of farmland inundation accurately. Inundation modeling should be performed by considering multiple time distributions of possible rainfalls, as digital forecasts of Korea Meteorological Administration is provided on a six-hour basis. As building multiple inputs and creating inundation models take a lot of time, it is necessary to shorten the forecast time by building a data base (DB) of farmland inundation probability. Therefore, the objective of this study is to establish a DB of farmland inundation probability in accordance with forecasted rainfalls. In this study, historical data of the digital forecasts was collected and used for time division. Inundation modeling was performed 100 times for each rainfall event. Time disaggregation of forecasted rainfall was performed by applying the Multiplicative Random Cascade (MRC) model, which uses consistency of fractal characteristics to six-hour rainfall data. To analyze the inundation of farmland, the river level was simulated using the Hydrologic Engineering Center - River Analysis System (HEC-RAS). The level of farmland was calculated by applying a simulation technique based on the water balance equation. The inundation probability was calculated by extracting the number of inundation occurrences out of the total number of simulations, and the results were stored in the DB of farmland inundation probability. The results of this study can be used to quickly predict the risk of farmland inundation, and to prepare measures to reduce damage from inundation.

Development of the PDA Based Mobile System for Body Fat Measurement and Diagnosis Using Bioelectrical Impedance Method (체임피던스 방법을 이용한 PDA 기반의 휴대용 체지방 측정 및 진단 시스템 개발)

  • 권세윤;이상민;김재환;우지환;김인영;이형기;방석원;김선일
    • Journal of Biomedical Engineering Research
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    • v.25 no.1
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    • pp.21-26
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    • 2004
  • Recently, many people want to know their state of health, such as a body fat rate, anywhere and anytime. The Personal Digital Assistance(PDA) is the portable wireless apparatus that has become widely popular. There are many application areas of the IDA to be in mobile care devices. In this study, we developed the PDA based body fat measurement system, composed of a cradle type measurement module and a WindowCE operated software module, a regression equation for predicting lean body mass (LBM). Sixty-three weight-stable subjects (53 men, 10 women) aged 20∼32yr participated in this study. A regression model, LBM = (0.0005*Height2 - 0.0160*Impedance + 0.3920*Weight - 0.0684*Age - 5.8141*Sex + 25.984, was found. The correlation coefficient( r) of body fat rate between developed system and HTM1000plus(BionetTM) was 0.928. HTM1000plus is a commercially available and approved by KFDA. These results indicated that developed system is reliable for estimation of body fat rate. Although developed system is the PDA based miniaturized, it shows good performance comparing with other commercial product.

An Analysis of Job Selection, Major-Job Match and Wage Level of College Graduates (대학 졸업생의 직업선택과 임금 수준)

  • Park, Jae-Min
    • Journal of Korea Technology Innovation Society
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    • v.14 no.1
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    • pp.22-39
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    • 2011
  • This study examines the wage level from a viewpoint of major-job match as part of an analysis on the skill mismatch problem in 4-year college graduates. The empirical analysis explicitly incorporate the sample selection bias as an econometric problem not only suggested but merely introduced in the earlier studies. This study also set up a major-job match variable, which was usually handled as a binary variable for analytical convenience, as a polychotomous choice variable in selection equation as provided by the survey. In particular, it considered multi-cohort survey on graduates of the years 1982, 1992, and 2002 for the empirical analysis. As a result of empirical analysis, the wage premium of a major-job match was identified. This result was consistent after the consideration of a sample selection bias and also after modeling the major-job match variable as polychotomously selective. Through an analysis classified by the major, this study identified a relatively high wage premium among Social Science, Engineering, and Science majors. However, there was a difference in the effect of selection among these majors. Also, by assessing cohort effects this study found that the skill mismatch had rapidly progressed in 1992, while difference between 1992 and 2002 cohorts are insignificant. The analysis suggests that wage level is better understood within the context of both sample selection and major-job match, and regardless of model specification the major-job match affects wage strongly.

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The Relationship Between Elementary School Students' Family Health and Internet Addiction: School Adjustment as a Mediating Variable (초등학생의 가족건강성과 인터넷 중독 간의 관계 : 학교적응을 매개변인으로)

  • Jang, Sung-Hwa;Park, Young-Jin
    • The Journal of the Korea Contents Association
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    • v.13 no.7
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    • pp.463-472
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    • 2013
  • The purpose of this study is to examine the relationships among three factors such as the family health, school adjustment and internet addiction, and their subordinated factors. The research is going to clarify if school adjustment has mediating effect in the relationship between the family health and internet addiction. 371 of elementary school students resideing in Dadjeon-city completed questionnaires assessing family health, school adjustment and internet addiction. The sample variance-covariance matrix was analyzed using SPSS 18.0 and AMOS 20.0, the mazimum likelihood minimization function. The goodness of fit was evaluated using the SRMR, RMSEA and its 90% confidence interval, CFI, and TLI. The results are as follows: First, there were significant correlations among family health, school adjustment and internet addiction. Second, the subordinated factors in the family health, school adjustment, and internet addiction regulation are also closely related in the statistically significant positive relationship excepting school adjustment. After conducting the Covariance Structure Analysis to verify the mediating effect of school adjustment in the relationship between the family health and internet addiction, we found that it was appropriate to explain our findings with the structural equation model. when the family health has an effect on internet addiction, the school adjustment partially influences this process. Finally, educational implications and suggestions for future studies are addressed.

Roles of Pride, Gratitude and Global Self-Corporate Brand Congruity in Corporate Association on Positive Behavior (기업연상의 기업제품에 대한 긍정행동효과에서 프라이드 및 고마움과 전체자아-기업브랜드 일치성의 역할)

  • Choi, Nak-Hwan;Ha, Koun-Su;Lim, Ah-Young
    • Journal of Distribution Science
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    • v.14 no.9
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    • pp.73-83
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    • 2016
  • Purpose - Previous studies have not paid attention to global self-corporate brand congruity and affective approach from the viewpoint of global self. This study explored an inducement of gratitude that, under the circumstance of corporate association, consumers feel toward corporate's responsible activities, pride related to corporate's ability, and global self congruity. Current researches also have examined positive behavior effects of global self-corporate brand congruity and the feelings on corporate products. Research design, data, and methodology - This research theoretically reviewed that corporate ability and social responsibility association would influence global self-corporate brand congruity, that corporate ability association could induce consumers' sense of pride, and that social responsibility association might induce gratitude. This study, furthermore, examined theoretically whether global self-corporate brand congruity, pride and gratitude could make consumers behave positively toward corporate products, and developed hypotheses. For the empirical analysis with the questionnaires, 231 employees and common people completed the questionnaires, and structural equation model of AMOS 18.0 was used. Results - From the empirical analysis, the outcomes are as followings. First, corporate ability association makes consumers feel proud. Second, corporate social responsible association makes consumers feel grateful. Third, both corporate ability association and social responsibility association let consumers be aware of global self-corporate brand congruity. Fourth, being conscious of each of pride, gratitude and global self-corporate brand congruity prompts consumers to behave positively toward corporate products. Fifth, mediation effects of pride and the congruity in the roles of corporate ability association on the positive behavior, and those of gratitude and the congruity in the roles of corporate social responsible association on the positive behavior are identified. Conclusions - Based on the results, it can be said that a marketing manager should endeavor to make consumers associate the corporate ability and social responsibility. However, the degree of consumers' feelings such as pride and gratitude can differ according to their cultural backgrounds. It is, therefore, needed to be explored by the types of feelings that can be caused more from the difference in cultural backgrounds by corporate association, and to be investigated differently and positively with behavioral effects on the corporate's products between the types.

Effects of Environmental Uncertainty on Transaction and Industry Characteristics in the Franchising Markets (환경불확실성이 프랜차이즈 시스템의 거래특성과 산업특성 및 성과에 미치는 영향)

  • Han, Sang-Lin;Baek, Mi-Young
    • Journal of Distribution Research
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    • v.13 no.3
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    • pp.55-77
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    • 2008
  • The purpose of this research is to understand the effects of environmental uncertainty on transaction characteristics, industry factors, and performance in Korean franchising markets. This research tried to investigate both the characteristics of B-to-C service factors and B-to-B industry factors of franchising industry from the perspectives of CLalt, trust, communication, and other important variables. Hypothetical research model was proposed and, by using SPSS and AMOS, research hypotheses and structural equation models were empirically tested and supported. The results showed that environmental uncertainty has negative effects on relationship characteristics and industry characteristics of franchise. Trust showed positive impact on the performance. Managerial implications and limitations of the study results were also discussed. Future research direction was suggested.

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An Analysis of the Effects of Consumer Characteristics and Consumer Trust on Purchase Intention of Environment-friendly Agricultural Products (소비자 특성과 소비자 신뢰가 친환경농산물의 구매의도에 미치는 영향 분석)

  • Kim, Mi-Song;Choi, Hyung-Kyu;Kim, Dong-Hwan
    • Journal of Distribution Science
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    • v.11 no.1
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    • pp.45-53
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    • 2013
  • Purpose - The environment-friendly agricultural product market in Korea sees continual high growth. Recently, the Korean government has been actively fostering environment-friendly agriculture as an engine of future growth. Korean people have increasingly become more health-conscious and interested in food safety issues. Many distribution and retailing companies have responded with various promotional activities. However, most of these are not strategic and appear to have unsatisfactory outcomes. The main purpose of this paper is to suggest effective marketing strategies for environment-friendly agricultural products. To achieve this aim, the study empirically investigates the effects of consumer characteristics and trust on the purchase intention of environment-friendly agricultural products. Research design, data, methodology - Based on the theory of planned behavior, and previous studies related to the purchase intention and consumption of environment-friendly agricultural products, we set up five study hypotheses. These related to the demographic characteristics of consumers, purchase intention, and behavior of the products. We then set up a study model and four study hypotheses relating to health consciousness, environmental consciousness, consumer trust level, purchase intention, and behavior of the products. The data were collected using a questionnaire given to consumers living in Seoul and southern Geonggi Province. The final sample size is 403 and mean age is 44.3. SPSS 15.0 for Windows and Amos 7.0 were used as statistical analysis tools. Meaningful results were derived using frequency analysis, correlation analysis, a t-test, and structural equation modeling. Results - Empirical results of this research are as follows. (1) First, it is shown that consumers consider such attributes as intimacy and health to be important when they buy environment-friendly agricultural products. (2) We also found that consumers recognize the value of environment-friendly agricultural products as high, but their trust level as low. (3) Consumer groups consisting of married couples, with higher education, higher income, and higher age are shown to have a higher intention of buying environment-friendly agricultural products than any other consumer group. (4) It is estimated that the level of consumer trust positively affects the purchase intention of environment-friendly agricultural products. The path coefficient (.138) between consumer trust and purchase intention is statistically significant at the α = .05 level. (5). It is also estimated that environmental consciousness positively affects purchase intention. The path coefficient (.245) between environmental consciousness and purchase intention is statistically significant at the α = 0.05 level. The standardized path coefficients of consumer trust and environmental consciousness with purchase intention are .556 and .288 respectively. Therefore, consumer trust affects purchase intention more than environmental consciousness. (6) Finally, purchase intention is estimated to positively affect purchase behavior. Conclusions - Based upon empirical results, this research suggests that marketers of environment-friendly agricultural products should focus more on increasing consumer trust levels, emphasizing the training and education of employees. The government also should pay attention to a standardized certification system for environment-friendly agricultural products. Marketers of environment-friendly agricultural products should consider the consumer groups of married couples, with higher education, higher income, and higher age as a major target segment.

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Social Identity Threat and Across-Domain Compensatory Consumption Intention (사회적 아이덴티티의 위협과 영역 외 보상소비의도)

  • CHOI, Nak-Hwan
    • The Journal of Industrial Distribution & Business
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    • v.10 no.11
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    • pp.35-47
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    • 2019
  • Purpose: Current study focused on investigating the effects of the self-dissociation as a thought in which consumers dis-identify or dissociate with the threatened in-group and the escapism as a tendency of consumers' distracting themselves and avoiding their thoughts about the in-group under severe but adoptable criticism by turning their attention elsewhere on across-domain compensatory consumption intention. And It explored not only the positive roles of undesirability thought against the in-group in consumers' forming the self-dissociation and the escapism, but also the effects of negative emotion to the in-group felt at the place of being exposed to the criticism against the in-group on the escapism. Research design, data, and methodology: The experiment was performed with the in-group-threatening single factor within-subject design. Questionnaire data were collected from 196 undergraduate students, and the data were used to testing research hypotheses by structural equation model of Amos 21.0. Results: First, both the self-dissociation of consumers' dis-identifying with the in-group criticized severely by others and the escapism of their deliberately directing their thoughts and distracting their attention away from thinking the in-group positively influenced on the across-domain compensatory consumption intention. Second, the negative emotion positively influenced on the escapism. Third, the undesirability thought to the in-group under the severe criticism positively effected on the self-dissociation as well as the escapism. Putting in the nutshell, the findings of this study are consistent with the idea that consumers can overcome the negative self-discrepancy on one dimension of their social identity by distracting themselves and avoiding thinking about the threatened in-group to find meaning on another dimension which might lead them to the place of doing the across-domain compensatory consumption. Conclusions - Focusing on the results of this study, checking which aspects of consumers' social identity are linked to products or brands is at issue to marketers when the consumers are faced with the criticism against the in-group. The marketers should build the messages about their products or brand not related to the checked aspects, and communicate the messages, to lead the consumers to the place of doing the across-domain compensatory consumption by their products or brands.