• Title/Summary/Keyword: Low conducting state

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Tri-branched tri-anchoring organic dye for Visible light-responsive dye-sensitized photoelectrochemical water-splitting cells (염료감응형 광전기화학 물분해 전지용 Tri-branched tri-anchoring organic dye 개발)

  • Park, Jeong-Hyun;Kim, Jae-Hong;Ahn, Kwang-Soon
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.06a
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    • pp.87-87
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    • 2010
  • Photoelectrochemical (PEC) systems are promising methods of producing H2 gas using solar energy in an aqueous solution. The photoelectrochemical properties of numerous metal oxides have been studied. Among them, the PEC systems based on TiO2 have been extensively studied. However, the drawback of a PEC system with TiO2 is that only ultraviolet (UV) light can be absorbed because of its large band gap (3.2 - 3.4 eV). Two approaches have been introduced in order to use PEC cells in the visible light region. The first method includes doping impurities, such as nitrogen, into TiO2, and this technique has been extensively studied in an attempt to narrow the band gap. In comparison, research on the second method, which includes visible light water splitting in molecular photosystems, has been slow. Mallouk et al. recently developed electrochemical water-splitting cells using the Ru(II) complex as the visible light photosensitizer. the dye-sensitized PEC cell consisted of a dye-sensitized TiO2 layer, a Pt counter electrode, and an aqueous solution between them. Under a visible light (< 3 eV) illumination, only the dye molecule absorbed the light and became excited because TiO2 had the wide band gap. The light absorption of the dye was followed by the transfer of an electron from the excited state (S*) of the dye to the conduction band (CB) of TiO2 and its subsequent transfer to the transparent conducting oxide (TCO). The electrons moved through the wire to the Pt, where the water reduction (or H2 evolution) occurred. The oxidized dye molecules caused the water oxidation because their HOMO level was below the H2O/O2 level. Organic dyes have been developed as metal-free alternatives to the Ru(II) complexes because of their tunable optical and electronic properties and low-cost manufacturing. Recently, organic dye molecules containing multi-branched, multi-anchoring groups have received a great deal of interest. In this work, tri-branched tri-anchoring organic dyes (Dye 2) were designed and applied to visible light water-splitting cells based on dye-sensitized TiO2 electrodes. Dye 2 had a molecular structure containing one donor (D) and three acceptor (A) groups, and each ended with an anchoring functionality. In comparison, mono-anchoring dyes (Dye 1) were also synthesized. The PEC response of the Dye 2-sensitized TiO2 film was much better than the Dye 1-sensitized or unsensitized TiO2 films.

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Current State and Improvement Measures of HACCP System Applying in Elementary School Lunch (HACCP 적용 초등학교급식에서의 시행실태와 개선방안)

  • Woo, Gun-Yeon;Park, Jae-Yong;Han, Chang-Hyun
    • Journal of the Korean Society of School Health
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    • v.16 no.2
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    • pp.13-23
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    • 2003
  • To provide data necessary for effectively applying the HACCP system by understanding the current application condition of HACCP system and satisfaction level of the dietician in elementary schools, a mail-in survey was conducted on dieticians serving for 227 elementary schools applying HACCP system in Kyungsangbuk-Do since November 1, 2001 to December 20, 2001. 83.5% of the subjected schools were conducting more than 50% of HACCP cooking process management, and the level of cooking process management displayed significant relevance according to the number of dieticians serving the school meals. The area that was not well conducted in the field of HACCP system was proven to be water examination(94.0%), inspection on self-sanitation of cooks prior to cooking(90.6%), and maintenance of dry kitchen floor(l4.8%). The reason why the above areas are not well conducted was because of lack of time due to over workloads. Subjective dieticians had pointed out improvement of sanitary concept(58.1%) and improvement of self-sanitation (28.8%) as benefits of applying HACCP. 21.2% of the subjective dieticians were satisfied with application HACCP and 35.2% were dissatisfied with applying HACCP. In case of which the duration of applying the HACCP was longer than one year and in case of higher rate of HACCP cooking process management and longer work experience of the dieticians, the level of satisfaction was proven to be significantly higher. The most difficult things to follow in important management categories according to the features of dietitian work and work experience were food distribution of CCP7 step and maintenance of optimum temperature(70.7%). Subjective dieticians had pointed out insufficient facility or environment and lack of inspection equipments in order regarding problems of applying HACCP. Also in the level of necessity of improvement categories in applying HACCP, dieticians had replied that facility and equipment improvement was mostly needed. Due to the induction of HACCP system in school meals, comparatively well cooking process management is being conducted, and I believe it could contribute in securing safety and quality improvement of school meal by improving the sanitation concept of the dieticians. However, the satisfaction level of dieticians are rather low and there are many difficulties in maintaining optimum temperature in the process of food distribution and transportation process. Also, lack of facilities and environment, lack of inspection equipments and etc are pointed out as problems of inducing HACCP. Thus, to settle HACCP system, it is believed that brave investment must be preceded.

Dose-Dependent Associations between Wine Drinking and Breast Cancer Risk - Meta-Analysis Findings

  • Chen, Jia-Yan;Zhu, Hong-Cheng;Guo, Qing;Shu, Zheng;Bao, Xu-Hui;Sun, Feng;Qin, Qin;Yang, Xi;Zhang, Chi;Cheng, Hong-Yan;Sun, Xin-Chen
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.1221-1233
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    • 2016
  • Purpose: To investigate any potential association between wine and breast cancer risk. Materials and Methods: We quantitatively assessed associations by conducting a meta-analysis based on evidence from observational studies. In May 2014, we performed electronic searches in PubMed, EmBase and the Cochrane Library to identify studies examining the effect of wine drinking on breast cancer incidence. The relative risk (RR) or odds ratio (OR) were used to measure any such association. Results: The analysis was further stratified by confounding factors that could influence the results. A total of twenty-six studies (eight case-control and eighteen cohort studies) involving 21,149 cases were included in our meta-analysis. Our study demonstrated that wine drinking was associated with breast cancer risk. A 36% increase in breast cancer risk was observed across overall studies based on the highest versus lowest model, with a combined RR of 1.0059 (95%CI 0.97-1.05) in dose-response analysis. However, 5 g/d ethanol from wine seemed to have protective value from our non-linear model. Conclusions: Our findings indicate that wine drinking is associated with breast cancer risk in a dose-dependent manner. High consumption of wine contributes to breast cancer risk with protection exerted by low doses. Further investigations are needed for clarification.

Retardation Effect and Mobility of a Heavy Metal in a Sandy Soil (사질토양에서의 중금속의 지연효과와 이동성)

  • Kim, Dong-Ju;Baek, Doo-Sung
    • Journal of the Korean Society of Groundwater Environment
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    • v.5 no.3
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    • pp.155-161
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    • 1998
  • Retardation effect of heavy metals in soils caused by adsorption onto the surfaces of solids particles is well known phenomenon. In this study, we investigated the retardation effect on the mobility of a Zn in a sandy soil by conducting batch and column tests. The column test consisted of monitoring the concentrations of effluent versus time known as a breakthrough curve (BTC). We used NaCl and ZnCl$_2$ solutions with the concentration of 10 g/L as a tracer, and injected them respectively into the inlet boundary of the soil sample as a square pulse type, and monitored the effluent concentrations at the exit boundary under a steady state condition using an EC-meter and ICP-AES. The batch test was conducted based on the standard procedure of equilibrating fine fractions collected from the soil with various initial ZnCl$_2$ concentrations, and analysis of Zn ions in the equilibrated solutions using ICP-AES. The results of column test showed that i) the peak concentration of ZnCl$_2$analyzed by ICP was far less than that of either NaCl or bulk electrical conductivity and ⅱ) travel times of peak concentrations for two tracers were more less identical. The relatively low concentration of Zn can be explained by ion exchange between Zn and other cations, and possible precipitation of Zn in the form of Zn(OH)$_2$due to high pH range (7.0∼7.9) of the effluent. The identical result of travel times of peak concentrations indicates that the retardation effect is not present in the soil. The only way to describe the prominent decrease of Zn ion was to introduce decay or sink coefficient in the CDE model to account for irreversible decrease of Zn ions in the aqueous phase.

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An Exploratory Study on Specialty Stores for Organic Foods

  • Lee, Young-Chul;Park, Chul-Ju;Lim, Su-Ji
    • Journal of Distribution Science
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    • v.9 no.3
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    • pp.47-54
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    • 2011
  • This paper presents exploratory research on consumer awareness and attitudesabout organic food, for which consumer demand continues to increase the paper also assesses consumers' organic food distribution channel preferences. By conducting a literature review, a case study has been carried out in order to glean customer behavior, market condition and typesof distribution channels, and development of specialty stores for organic foods. The early research indicates that consumer awareness and customer attitudes toward organic food are mostly positive however, organic food's high price, as well as a lack of organic food stores, cause a negative effect on consumers' purchase intention. Secondly, the U.S. organic food retail channel consists of such mainstream supermarket/grocery stores and leading natural and organic food supermarket chains as Whole Foods, Trader Joe's, and Sunflower Farmers Market. For the current retail distribution of organic food in Korea, off-line stores are composed of direct management stores and franchise chains. Most of the organic food retail distribution operates through the Internet shopping mall, and are commonly located at retail distribution centers as multi-channel, shop-in-shop stores. Moreover, unlike in the U.S., association and consumers' cooperatives (Co-Ops), and such other member-direct retail stores as Hansallim, iCOOP, Nature Dream,and online shopping malls, are all active in Korea. Thirdly, as a result of an analysis of the present state of the organic food retail channel, as well as building a case for organic food specialty stores, the distinctive featuresand rapid growth of such unique organic food stores as Whole Foods Market, or Trader Joe's successful downsizing strategies, as well as Sunflower Farmers Market low-price approach, show steady industry growth. Moreover, as a result of a case studyof such domestic representative organic food specialty stores as "Olga" and "Chorokmaeul," a similar management style to the United States' "Whole Foods Market" and "Trader Joe's," respectively, can be seen. Similar to the U.S. market, Korean organic food markets should also implement active retail distribution opportunities, allowing consumers to select from various diverse and differentiated choices. In order to accomplish this goal, it is necessary to prepare such measures as sustaining reasonable prices, securing various suppliers for unique products,and improving consumer trust through advertisement strategies that are suitable for each company's branding processes.

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A Research on Effect of Corporate's Competitive Advantage to the R&D Investment in Small and Medium Enterprise (중소기업 유형별 연구개발투자의 영향요인에 관한 실증연구)

  • Choi, Su-Heyong;Choi, Chul-An
    • Management & Information Systems Review
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    • v.33 no.1
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    • pp.191-217
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    • 2014
  • The Purpose of this study is to find the effect factors of R&D investment in SMEs which plays an important role in the national economy, and the differences of the effect factors by the type of SMEs. The subject of this study is about 3,400 SMEs mentioned in "The survey of technical statistics on SMEs in 2007" by Korea Federation of Small and Medium Business. The effect factors are related with the size of business, the infrastructure of R&D and the activities of R&D which have been studied by many researchers. The methods of analysis are regression analysis, moderating effect analysis and the software package used is SPSS 12.0. The results of the study are as fallow. First, it was found that unlike in previous studies which show the effect of the elements of business's size, research infrastructure, research activities on R&D investment, one element alone can't be considered for meaningful result but the various elements have effect on R&D investment at the same time. In other words, the number of employees and the sales as the elements of business's size, the ratio of researchers, the technical ability, the ratio of equipment possession and the intellectual properties as the elements of R&D infrastructure, the activity of ideas and joint research as the elements of R&D activities have positive(+) effect, whereas the participation of CEO in the activity of R&D as the elements of R&D activities activity has negative(-) one. The number of employees, the ratio of researchers, and the sales had relatively high influence whereas equipment possession, technical ability, intellectual properties, the participation of CEO in the research, the activity of idea, joint research had relatively low influence. Next, it was also found that there are differences of the effect factors over the types of SMEs. SMEs were classified into 19 types by eight criteria such as start-ups and existing business by business age; small business and medium business by size; manufacturing business and service business by product type;independent business and subcontractor business by dealing type; businesses in the entering, growing, maturing and restructuring stage by growth stage; businesses with low, medium and high technology by technological level; pioneering business and non-pioneering business by industrial type; and businesses with state-of-the-art technology and non-advanced business by the level of business activities. The meaning of this study lies in the fact that it found the various effect factors should be considered at the same time when conducting study on SMEs' R&D investment, and the differences by the type should be acknowledged. This study surpassed the limitations of the previous studies which focused on a couple of factors and types. This study result can also be considered for other studies on achievement, organization, marketing and others. Moreover, it shows that a differential policy by business type is needed when formulating SME policy.

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Factors Influencing the Pros and Opposite of Life-Sustaining Treatment in the Elderly: Focusing on the Values of Cohabitation with Children and the Cost of Living in Old Age (노인의 연명의료에 대한 찬반 의견에 영향을 미치는 요인: 자녀동거와 노후생활비에 대한 가치관을 중심으로)

  • Mee-Ae Lee
    • Journal of Industrial Convergence
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    • v.21 no.3
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    • pp.159-169
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    • 2023
  • This study analyzed the factors affecting the opinions of life-sustaining treatment among the elderly in Korea. The study subjects were 10,097 people who responded to the survey on the condition of the elderly (2020), and using the SPSS 25.0 program, first, the demographic characteristics of the research subjects were identified through descriptive statistics and the average and normality of major variables were identified. Second, the chi-square was analyzed by conducting a cross-analysis of opinions on life-sustaining treatment according to the characteristics of the elderly. Third, a correlation analysis was performed to analyze the correlation between major variables. Fourth, the relative influence on the life-sustaining treatment of the elderly was identified through multiple regression analysis. The main research findings are as follows. First, 8,565 (84.8%) of the elderly were opposed to medical treatment (life-sustaining treatment) to save them even if they were unconscious or difficult to live. Second, as a result of cross-analysis on life-sustaining treatment for the elderly, the 𝑥2 values of education level, health status, living together with children, and cost of living in old age were found to be significant. Third, the educational level of the elderly, living together with children, and the cost of living in old age were found to have statistically significant negative effects on life-sustaining treatment. Such research results indicate that the elderly with a high level of education oppose life-sustaining treatment compared to those with a low level of education. In addition, in the case of the elderly with traditional values who responded that one of their children should live with the elderly (parents), the ratio of people in favor of life-sustaining treatment was high, and in the case of the elderly with modern values who responded that they did not have to live together, the ratio of opposition to life-sustaining treatment was high. appeared to be high. In addition, in the case of the elderly with traditional values who responded that the burden of living expenses in old age should be shared between the state and society and their children, the proportion in favor of life-sustaining treatment was high. This high figure expressed the desire for well-dying. Based on these research results, the value system was re-examined as a factor influencing the elderly's opinion on life-sustaining treatment, and basic data for welfare policies for the elderly were provided.

A Study on the Support System for Reinforcement of Competitiveness of Small Business persons - Mainly Focused on Support System for Small Business Persons - (소상공인 경쟁력 강화의 지원제도에 관한 연구 - 소상공인 지원제도를 중심으로 -)

  • Woo, Dae-IL;Lee, Sang-Youn
    • The Korean Journal of Franchise Management
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    • v.2 no.2
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    • pp.95-110
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    • 2011
  • As global economic conditions are getting uneasy and polarization of our economy is intensified, the economic sentiment of small businesses is still low and unstable. The collapse of worldwide banking systems due to sub prime crisis in 2007 became the catalyst that shakes financial industries in each country in the world; the most sentiment people, small businesspersons, also have hard time facing survival way out, facing a great crisis. All organizing powers including manufactures, wholesales and retails are being gradually greater in mutual relations and dependence, and unstable factors about risks are also increasing. For exterior environmental and physical risk factors which cannot make small businesses survive themselves by developing ways out are eventually increasing, those who cannot cope with these factors face a great crisis. Although the government tries hard to overcome this situation conducting many ways, the effect does not continue. It is the real state that independent business markets including overall employment and establishing business have vicious cycle that they cannot be improved, due to increase of employment centered on short-term labors which lack durability in creation of employment and decline of household income. Recently, growth shows indication of slowdown because of multinational risk factors including financial crisis in each country in Europe, the death of Kim Jung-il, relationship with North Korea, and unstability of war situation in the Middle East Asia. Experts expect that growth rate will be about 4%, and independent business that ordinary people feel is still gloomy. It's reality that there is no adequate alternative for lack of jobs, unstable employment and a means of living after retirement. Also, the fact that large companies enter the market which is narrow and in the excessive competition should be an environmental factor that makes the situation worse. The business concept, a franchise, is the part we should think about whether it is the institutional solution that can guarantee independent businessmen stable life. Major companies are frightfully entering the market today, breaking the barrier to entry and shouting of a win-win with independent businesses. It's the small businesspersons who go through painful domestic recession, cannot predict the future and manage confusing and unstable independent business. It's very important to restore the domestic economy through wisely boosting consumption as soon as possible. It's also important to lead the situation by gathering powers of the government and related organizations, agonizing, suggesting solutions, and establishing accurate directions. The purpose of this study, therefore, is to suggest ways to strengthen competitiveness of small businesspersons by examining small business support policies which are currently implemented.