• Title/Summary/Keyword: first-order necessary condition

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Estimation on Heating and Cooling Loads for a Multi-Span Greenhouse and Performance Analysis of PV System using Building Energy Simulation (BES를 이용한 연동형 온실의 냉·난방 부하 산정 및 PV 시스템 발전 성능 분석)

  • Lee, Minhyung;Lee, In-Bok;Ha, Tae-Hwan;Kim, Rack-Woo;Yeo, Uk-Hyeon;Lee, Sang-Yeon;Park, Gwanyong;Kim, Jun-Gyu
    • Journal of Bio-Environment Control
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    • v.26 no.4
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    • pp.258-267
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    • 2017
  • The price competitiveness of photovoltaic system (PV system) has risen recently due to the growth of industries, however, it is rarely applied to the greenhouse compared to other renewable energy. In order to evaluate the application of PV system in the greenhouse, power generation and optimal installation area of PV panels should be analyzed. For this purpose, the prediction of the heating and cooling loads of the greenhouse is necessary at first. Therefore, periodic and maximum energy loads of a multi-span greenhouse were estimated using Building Energy Simulation(BES) and optimal installation area of PV panels was derived in this study. 5 parameter equivalent circuit model was applied to analyzed power generation of PV system under different installation angle and the optimal installation condition of the PV system was derived. As a result of the energy simulation, the average cooling load and heating load of the greenhouse were 627,516MJ and 1,652,050MJ respectively when the ventilation rate was $60AE{\cdot}hr^{-1}$. The highest electric power production of the PV system was generated when the installation angle was set to $30^{\circ}$. Also, adjustable PV system produced about 6% more electric power than the fixed PV system. Optimal installation area of the PV panels was derived with consideration of the estimated energy loads. As a result, optimal installation area of PV panels for fixed PV system and adjustable PV system were $521m^2$ and $494m^2$ respectively.

A Study on Removal of Organism and Nitrogen, Phosphorus in Wastewater Treatment Process Using Nitrifier Activated Reactor (질산화균 활성화조를 이용한 하수처리 공정에서의 유기물 및 질소, 인 제거에 관한 연구)

  • Dong, Young-tak;Seo, Dong-whan;Bae, Yu-jin;Park, Ju-seok
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.6
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    • pp.727-735
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    • 2007
  • The use of water by cities is increasing owing to industrialization, the concentration of population, and the enhancement of the standard of living. Accordingly, the amount of waste water is also increasing, and the degree of pollution of the water system is rising. In order to solve this problem, it is necessary to remove organisms and suspended particles as well as the products of eutrophication such as nitrates and phosphates. This study developed a high-end treatment engineering solution with maximum efficiency and lower costs by researching and developing a advanced treatment engineering solution with the use of Biosorption. As a result, the study conducted a test with a $50m^3/day$ Pilot Scale Plant by developing treatment engineering so that only the secondary treatment satisfies the standard of water quality and which provided optimal treatment efficiency along with convenient maintenance and management. The removal of organisms, which has to be pursued first for realizing nitrification during the test period, was made in such a way that there would be no oxidation by microorganisms in the reactor while preparing oxygen as an inhibitor for the growth of microorganism in the course of moving toward the primary settling pond. The study introduced microorganisms in the endogeneous respiration stage to perform adhesion, absorption, and filtering by bringing them into contact with the inflowing water with the use of a sludge returning from the secondary settling pond. Also a test was conducted to determine how effective the microorganisms are as an inner source of carbon. The HRT(Hydraulic Retention Time) in the nitrification tank (aerobic tank) could be reduced to two hours or below, and the stable treatment efficiency of the process using the organisms absorbed in the NAR reactor as a source of carbon could be proven. Also, given that the anaerobic condition of the pre-treatment tank becomes basic in the area of phosphate discharge, it was found that there was excellent efficiency for the removal of phosphate when the pre-treatment tank induced the discharge of phosphate and the polishing reactor induced the uptake of phosphate. The removal efficiency was shown to be about 94.4% for $BOD_5$. 90.7% for $COD_{Cr}$ 84.3% for $COD_{Mn}$, 96.0% for SS, 77.3% for TN, and 96.0% for TP.

The New X-ray Induced Electron Emission Spectrometer

  • Yu.N.Yuryev;Park, Hyun-Min;Lee, Hwack-Ju;Kim, Ju-Hwnag;Cho, Yang-Ku;K.Yu.Pogrebitsky
    • Proceedings of the Korea Crystallographic Association Conference
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    • 2002.11a
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    • pp.5-6
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    • 2002
  • The new spectrometer for X-ray Induced Electron Emission Spectroscopy (XIEES) .has been recently developed in KRISS in collaboration with PTI (Russia). The spectrometer allows to perform research using the XAFS, SXAFS, XANES techniques (D.C.Koningsberger and R.Prins, 1988) as well as the number of techniques from XIEES field(L.A.Bakaleinikov et all, 1992). The experiments may be carried out with registration of transmitted through the sample x-rays (to investigate bulk samples) or/and total electron yield (TEY) from the sample surface that gives the high (down to several atomic mono-layers in soft x-ray region) near surface sensitivity. The combination of these methods together give the possibility to obtain a quantitative information on elemental composition, chemical state, atomic structure for powder samples and solids, including non-crystalline materials (the long range order is not required). The optical design of spectrometer is made according to Johannesson true focusing schematics and presented on the Fig.1. Five stepping motors are used to maintain the focusing condition during the photon energy scan (crystal angle, crystal position along rail, sample goniometer rail angle, sample goniometer position along rail and sample goniometer angle relatively of rail). All movements can be done independently and simultaneously that speeds up the setting of photon energy and allows the using of crystals with different Rowland radil. At present six curved crystals with different d-values and one flat synthetic multilayer are installed on revolver-type monochromator. This arrangement allows the wide range of x-rays from 100 eV up to 25 keV to be obtained. Another 4 stepping motors set exit slit width, sample angle, channeltron position and x-ray detector position. The differential pumping allows to unite vacuum chambers of spectrometer and x-ray generator avoiding the absorption of soft x-rays on Be foil of a window and in atmosphere. Another feature of vacuum system is separation of walls of vacuum chamber (which are deformed by the atmospheric pressure) from optical elements of spectrometer. This warrantees that the optical elements are precisely positioned. The detecting system of the spectrometer consists of two proportional counters, one scintillating detector and one channeltron detector. First proportional counter can be used as I/sub 0/-detector in transmission mode or by measuring the fluorescence from exit slit edge. The last installation can be used to measure the reference data (that is necessary in XANES measurements), in this case the reference sample is installed on slit knife edge. The second proportional counter measures the intensity of x-rays transmitted through the sample. The scintillating detector is used in the same way but on the air for the hard x-rays and for alignment purposes. Total electron yield from the sample is measured by channeltron. The spectrometer is fully controlled by special software that gives the high flexibility and reliability in carrying out of the experiments. Fig.2 and fig.3 present the typical XAFS spectra measured with spectrometer.

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A Study on the Factors Affecting the Entry of Depression by Life Cycle - Focusing on the Comparison of the Three Generations of Adulthood, Middle Age and Old Age - (생애주기별 우울진입에 영향을 미치는 요인에 관한 연구 - 성년, 중년, 노년층의 3세대 비교를 중심으로 -)

  • Jeong, Jun Su;Lee, Hye Kyung
    • Korean Journal of Social Welfare
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    • v.69 no.2
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    • pp.117-141
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    • 2017
  • The purpose of this study is to investigate the differences of the factors affecting the entry of depression by generations and to present a practical strategy for preventing of depression by life-cycle. For this purpose, we analyzed the factors influencing the depression of adults, middle-aged and elderly people through the discrete-time hazard model. The results of this study are as follows: First, the lower the self-esteem, the lower the income satisfaction and the family satisfaction people have, the higher the likelihood of entering the depression they have. In addition, age, educational level, health status, presence of chronic diseases, employment status, regional area, and leisure life satisfaction were variables that showed difference by generation. In the case of adulthood(aged 20 ~ 39), unemployed persons are more likely to enter the depression than younger workers. On the other hand, the middle-aged(40 ~ 64 year olds) are more likely to enter the depression if they are older, have poor health status, have no chronic disease, and have low leisure satisfaction. Finally, older people(aged 65 and over) are more likely to enter the depression when the education level is higher, the health condition is worse, and the leisure satisfaction is lower. If they lived in an urban and rural complex, they are more likely to enter the depression. Based on these results, it is necessary to establish a support plan reflecting the characteristics revealed by generations in order to prevent the entry of depression.

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Effect of Mothers' Oral Health Knowledge and Behaviour on Dental Caries in Their Preschool Children (데이터마이닝을 이용한 유치치아우식증 관련요인 분석)

  • Kim, Jin-Soo;Kim, Hyo-Jin;Jorn, Hong-Suk
    • Journal of Korean society of Dental Hygiene
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    • v.5 no.2
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    • pp.171-184
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    • 2005
  • In order to investigate correlation between mother's dental ca re for her children and their dental caries, this study was conducted wi th the dental examination record of 365 children who showed the same number of questionnaires with those examined for dental conditions and questionnaires written by mothers among children between three and six years of age and their mothers in Yeoncheon, Gyeonggi province in June 2004 to estimate frequency and percentage of general properties of subjects and mother's oral health care behaviors for her children by research items, to carry out cross-tabulation analysis and correlation analysis following Chi-square distribution for the presence of dental caries in deciduous teeth and oral health care behaviors, and to use decision tree analysis among data mining techniques for those factors associated with the presence of dental caries in deciduous teeth, and drew the following conclusions. 1. For mother's oral health care behaviors and attitudes for her children, 225 mothers(61.6%) confirmed their children's teeth-brushing; 278(76.2%) used no fluorine; and 286(78.6%) observed their children's teeth, 322 mothers(88.2%) instructed their children in teeth-brushing while 268 (73.4%) provided dental care, 232 mothers(63.7%) treated their children's cavity; 290(79.4%) believed that their children had good dental conditions; and 294(80.5%) answered that they began to provide their children with dental care in deciduous teeth. 2. As for the presence of dental caries in deciduous teeth and dental health care behaviors, there were statistically significant differences in employment, confirmation after teeth-brushing, teeth observation, instruction in time for teeth-brushing, use of fluorine, cavity treatment, time for dental care, and perception of dental conditions(p<0.05). 3. As for correlation between dental caries in deciduous teeth and oral health care behaviors, mothers who worked, who believed that their children didn't have good dental condition, and who thought that it was necessary to begin to provide dental care in permanent teeth were found to get their children to suffer from dental caries in deciduous teeth. Besides, those who failed to confirm teeth-brushing, who used no fluorine, and who failed to observe teeth and gave no instruction in time for teeth-brushing were shown to get their children to suffer from dental caries in deciduous teeth. 4. Variables to determine the presence of dental caries in deciduous teeth were classified by cavity treatment, mother's employment, time for dental care, and observation of children's teeth. The first node to determine the presence of dental caries in deciduous teeth was found to be cavity treatment; the next criteria for classification after cavity treatment were shown to be mother's employment and time for dental care. In case of children with no cavity, they were found to be mother's employment and teeth observation.

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Spatial Analysis of the Confucian Cultural Landscapes at Jeongeuihyanggyo, Jeju Island (제주도 정의향교의 유교문화경관에 대한 공간분석)

  • Lee, HaengLyoul
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.4
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    • pp.29-42
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    • 2017
  • Jeongeuihyanggyo(旌義鄕校) is a kind of traditional, Confucian cultural landscapes that is located in Jeju special self-governing province. Its historical background illustrates that the first erection was started at Goseong-li of Seongsan-eup(城山邑 古城里) at Taejong(太宗) of 16 years(1417) and it moved to the west gate of Hyunseong(縣城) at Heojong(憲宗) of 15 years,(1849) Joseon. The aim at this study is to reveal characters of these Confucian Spatial Composition and Order, which are valuable resources that can be created into the cultural contents. The results demonstrate the characters of the Confucian cultural landscape as followings; the changing process of new building and its relocation, the utilization of antique maps in location interpretation of Jeongeuihyanggyo, Confucian symbolic elements of it, the spatial compositions and layouts of its buildings, physical structures, main buildings and their characters, locational points of topographic profile, changes of axial line at Daeseongjeon(大成殿), the D/H ratio of its courts. This study can show that Jeongeuihyanggyo is a case for realizing the Confucian reformation to enhance Seongeup Hyun's education standard considering the locality of the site which is an isolated island like Jejudo(濟州島). The author can see that the example of Confucian space is applied to various layout techniques, both horizontally and vertically, in a limited space condition of being in the castle. Therefore, it is necessary to revive this point so that it can utilize unique Confucian cultural landscape possessed only by Jeongeuihyanggyo.

An exploration of the factors affecting the social capital building of the youth (청년층의 사회적 자본 형성에 영향을 미치는 요인 탐색)

  • Kim, Young-sik;Shin, Cholkyun;Moon, ChanJu
    • Journal of vocational education research
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    • v.37 no.4
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    • pp.45-66
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    • 2018
  • The purpose of this study is to explore the factors affecting the social capital of youth and to draw implications for the policies related to development of the social capital of them. To this end, we utilized the OLS regression model and the quantile regression model exploiting the 12th year dataset of the Korean Education & Employment Panel(KEEP). First, this study shows that the effect on trust is higher than that of the counterpart when the case is a) unmarried, b) with the high level of education, c) with a large asset, d) with high self-respect and the satisfaction for financial situation, and e) social media user. On the other hand, the higher the monthly average income, the lower the trust level. In addition, when the cases are grouped into 25 quantile, 50 quantile, and 75 quantile according to the level of trust, it is revealed empirically that the factors affecting social capital formation are somewhat different. Second, this study also shows that the effect is higher in a specific condition. The effect is higher compared to the counterpart when the case is a) male, b) with children, c) metropolitan city resident, d) non-employee, e) with a large asset, f) with high level of happiness, g) with high expense of purchasing books, and h) social media user. As a result, it is found that there are no personal characteristics that have statistically significant influence on students belonging to the 25th quantile of social capital. This study suggests that, in order to support the formation of social capital of Korean youths, it is necessary to enhance their psychological satisfaction and to provide cultural support or policies. In addition, it suggests that a tailored social capital accumulation program is needed according to the level of social capital, and the support for this need to be changed according to the amount of social capital of young people.

Knowledge, Attitude & Practice for Sexuality of Teachers -Based on over 50 year old teachers- (교사의 성 지식.태도.실태 연구 -50세 이상 교사를 중심으로-)

  • Lee, Eun-Jung;Park, Young-Soo;Choi, In-Sook
    • The Journal of Korean Society for School & Community Health Education
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    • v.5
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    • pp.107-122
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    • 2004
  • To correctly plant the value of sex to the juvenile, we cannot overemphasize the importance of the sexual education in schools. Therefore, the study for teachers' consciousness and view of sex is also necessary, because they are subjects of education and role-models of sex of their students. Especially, if teachers are over fifty in age, it is more important, because it is obvious, as they are in positions of managers and directors of education, that their view of sexual value and consciousness are influencing the aim of education and the course of education. Hereby this study was conducted to check their sexual consciousness, attitude, and condition and to prepare for the basic data needed for the development of a sexual education program suitable to them. The methods of the survey of this study are applied by modifying or supplementing those of precedented studies. They are used after analyzing reliance of items according to Cronbach's $\alpha$ figure calculating law, and modifying or supplementing items lower in reliance. The questionnaire survey was conducted among 1,000 randomly selected from teachers working in middle and high schools in Korea from June 14th in 2004 to June 30th. The survey analyzed 632 questionnaires suitable to it. The outcomes of the survey of this study are like the following: First, the objects of the survey consist of 64.6% men and 35.4% women. Among them, 41.1% are under fifty and the rest are over fifty. As for the periods of marriage, 15.5% are unmarried, 16.3% are under ten years, 18.0% are between ten and twenty, and 50.2% are over twenty. Second, with reagard to sex, 25.6% admit the necessity of a heterosexual friend. 32.0% say that they are conservative to sex. 54.1% are taught sexual education. 67.1% attribute sexual education to nursing teachers. Third, among those who answer that they enoughly know the concept of sex, seenig by age, 25.0% are under fifty and 58.1% are over fifty. Seening by the periods of marriage, 9.2% are unmarried, 28.2% are under ten, 49.1% are between ten and twenty, and 59.0% are over twenty. Among those who answer that they enoughly know the concepts of sexual harassment and sexual violence, seenig by age, in the turns by above-mentioned order, each 47.7% and 76.3%. Seening by the periods of marriage, each 9.2%, 28.2%, 49.1%, and 59.0%. Fourth, among those who answer that "teachers also need sexual education and sexual counsel," by age, each92.7% and 91.4%. By the periods of marriage, each 89.8%, 95.2%, 89.4%, and 92.4%. As a matter of course, we can infer the necessity of the sexual education and sexual counsel for teachers. Fifth, among those who answer that they are satisfied with their sexuality, by age, each 41.1% and 61.3%. By the period of marriage, each 4.1%, 63.1%, 64.1%, and 61.5%. As for the sexual desire like spiritual intercourse, physical intercourse containing sexuality, by age, each 71.9% and 93.5%. By the periods of marriage, each 54.0%, 81.5%, 90.3%, and 93.0%. The survey shows that those over fifty and having long marriage are feeling the stronger desire towards sexuality. Through the outcomes of this survey, a few suggestions are possible: First, it is necessary to check of the teachers' view of sexual value and to study deep about the sexual tendency of them in twenties, thirties, and forties. It is to make them teach their students on the firm basis, and also to develop suitable sexual education and counsel program.

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Policy suggestions for active reporting of medical professionals for early detection of child abuse (아동학대의 조기발견을 위한 제도적 개선 방안: 「아동학대범죄의 처벌 등에 대한 특례법」이 정한 의료인에 의한 신고를 중심으로)

  • Bae, Seung Min;Lee, Sun Goo
    • The Korean Society of Law and Medicine
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    • v.18 no.1
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    • pp.143-169
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    • 2017
  • The Act on Special Cases Concerning the Punishment, etc. of Child Abuse Crimes intends to encourage reporting and punishment of child abuse by using the concept of 'crime' in child abuse cases. Article 10 of the Act imposes duty to report child abuse on a number of different professions, including medical professionals. Currently, more than 80% of child abuse cases occur among family members and the detection rate of child abuse is as low as 0.5% in Korea. On the other hand, medical professionals can identify child abuse relatively clearly with specific medical opinions. Therefore, it is necessary that medical professions are informed of this duty and does not bear disincentive from reporting. This paper makes policy suggestions in this regard. First, it is necessary that medical students and medical professionals receive regular education about the obligation to report child abuse. Education should include details of the reporting duty, as well as the fact that there is legal obligation to report even if the child abuse is "suspicious", not certain. Second, it is imperative to establish and implement protective programs for medical professionals who report child abuse. The current law provides a rough framework for protection of people who report child abuse, but it is necessary to produce detailed guidelines that are applicable in the context of medical setting. Education for medical students and medical professionals should include the contents of these guidelines, so that they do not hesitate reporting because they fear the aftermath of reporting. Third, it is highly recommended that physicians use the national Baby/Infant Health Checkup Program as an opportunity to detect child abuse. In Korea, the Baby/Infant Health Checkup Program provides physicians to periodically monitor health condition of all babies and children until the age of 71 months. In order to utilize this program for early detection of child abuse, it is imperative that the bBaby/Infant Health Checkup Program is modified to involve child abuse experts and medical professionals who participate in the program are educated about child abuse.

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A Study on the Variables Affecting the Intention to Use Healing Agriculture (치유농업 이용의도에 영향을 미치는 변인 고찰)

  • Kim, Ok Ja;Ha, Kyu Soo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.13 no.4
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    • pp.59-72
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    • 2018
  • The purpose of this study is to investigate the factors affecting the intention to use healing farming by setting aged readiness, rural healing supply condition, and rural healing service as independent variables. This study has been started based on the idea that it is necessary to provide healing service through healing agriculture to the rapidly increasing elderly people and urban people who need mental rest. Therefore, the purpose of this study is to find out the various factors influencing intention to use healing agriculture through empirical analysis. Second, we want to examine whether the variables influenced the intention to use more. Third, based on the results of these tests, we suggest the policy for activation of healing agriculture by examining the factors necessary for the promotion of physical and mental health of the elderly in the aging society and the revitalization of healing agriculture for the mental healing of the urban people. For this study, a questionnaire survey was conducted for men and women over 30 years old, and the final 356 copies were analyzed. The validity of the research hypothesis was verified by linear regression analysis. The results of the analysis are as follows. First, the physical preparation, emotional preparation, and economic preparation of aged care preparations were found to have a significant effect on intention to use. Second, natural landscape, accessibility, and stability of rural healing supply conditions were found to have a significant effect on intention to use. But economics and expertise were dismissed. Third, crop cultivation, animal medication and healing facilities of rural healing service were proved to have significant influence on intention to use. In order to increase the utilization of healing agriculture, it is necessary for the consumer to be well prepared for aging. In rural healing supply conditions, accessibility and safety should be provided for healing facilities in rural healing services.And to increase the intention to use it.