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        검색결과 16

        2.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The object of this study is to feasibility assesment for co-digestion efficiency of food waste recycling wastewater(FWR) with thermal hydrolysis process dehydration cake (THP Sludge). As a result of THP pre-treatment experimental conditions to 160oC and 30 minutes, the solubility rate(conversion rate of TCOD to SCOD) of the THP sludge increased by 34%. And the bio-methane potential in the THP sludge increased by about 1.42 times from 0.230 to 0.328 m3 CH4/kg VS compared to the non-pre-treatment. The substrates of the co-digestion reactor were FWR and THP sludge at a 1:1 ratio. Whereas, only FWR was used as a substrate in the digestion reactor as a control group. The experimental conditions are 28.5 days of hydraulic retention time(HRT) and 3.5 kg VS/m3-day of organic loading rate(OLR). During the 120 days operation period, the co-digestion reactor was able to operate stably in terms of water quality and methane production, but the FWR digestion reactor deteriorated after 90 days, and methane production decreased to 0.233 m3 CH4/kg VS, which is 67% of normal condition. After 120 days of the experiment, organic loading rate(OLR) of co-digestion reactor was gradually increased to 4.5 kg VS/m3-day and operated for 80 days. Methane production during 80 days was evaluated to be good at the level of 0.349 m3 CH4/kg VS. As a result of evaluating the dehydration efficiency of the sludge before/after 150-180oC THP using a filter press, it was confirmed that the moisture content of the sludge treated before THP at 180oC was 75% and improved by 8% from 83-85% level. Therefore, it is expected that the co-digestion reactor of FWR and THP sludge will ensure stable treatment water quality and increase bio-methane production and reduction effect of dehydration sludge volume.
        4,500원
        3.
        2017.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Excessive body weight gain during the growth period of early life may predispose individuals towards obesity and metabolic disorder in later life. We investigated the possibility of using the food efficiency ratio as an early indicator for predicting susceptibility to diet-induced obesity and insulin resistance. Four-week-old, prepubertal, male Sprague Dawley rats were divided into obesity-prone and obesity-resistant groups based on food efficiency ratio values after five days on a high-fat diet. Metabolic parameters measured after 2, 6, and 10 weeks, and specific phenotypes were compared with each group. Obesityprone rats had higher increases in body weight and fat mass compared to obesity-resistant rats over the study period. Obesity-prone rats became glucose intolerant early in this study and remained so throughout the experimental period, with increases in fat weight and leptin levels occurring first, followed by increases in insulin level. Gluconeogenesis and insulin resistance significantly increased in obesity-prone groups in which activities of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase were increased and glucokinase activity decreased. Higher food efficiency ratio at an early age was closely correlated with body fat accumulation, hyperleptinemia, and hyperinsulinemia of middle and elderly age. We suggest a high food efficiency ratio in prepubertal subjects may be a useful predictor of future obesity and insulin resistance.
        4,200원
        4.
        2016.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        With the interest on operational efficiency due to the rapid growth of food material distribution industry and food service industry, the study adopts DEA (Data Envelopment Analysis) model and examines to measure the technological, pure technical and scale efficiency those companies engaging in the food material distribution and food service business. As a result of analysis, the companies operating integrated business have relatively higher efficiency than those operating only food material distribution or food service companies while the result indicates that three efficiencies don’t have significant difference depending on whether affiliated companies or not. In the results from the measuring by DEA.
        4,000원
        5.
        2015.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study is to analyze the efficiency of Korean sea food manufacturing using Data Envelopment Analysis. Firstly, based on an output oriented traditional CCR, BCC model, the study estimated the efficiency scores. The average estimates of technical, pure technical, and scale efficiency turned out 0.6517, 0.7184, 0.9074 respectively, which are separated for 50 marine corporations. The 10 DMUs were efficient under CCR model while the 17 DMUs under BCC model. Also, the study suggested that the operating profit of the two output factors should be more increased relatively and averagely from the viewpoint of efficiency improvement. Secondly, super efficiency scores are estimated under super efficiency and SBM model. As a result, it came to be possible to distinguish and rank the efficiency of the efficient DMUs. The highest score was 4.2975 under Super-CCR, was 2.4947 under Super-BCC, was 2.7160 under SBM-Super- CCR, and was 1.5319 under SBM-Super-BCC model. The average estimates of super efficiency were 0.76 and 0.82 under Super-CCR and Super-BCC model respectively, and were 0.61 and 0.67 under SBM-Super- CCR and SBM-Super-BCC model. Finally, the study conducted a rank-sum test, Wilcoxon-Mann-Whitney test, to find a statistical significance of heterogeneity existing in efficiencies among the sample corporations. The result showed that there was a significant difference in average efficiency between Dried, Salted product manufacturing and Frozen product manufacturing under BCC-Super efficiency model at 10% level of significance. Furthermore, TOBIT model was applied to find out the potential factors that might influence the efficiency, Wilcoxonand the results showed debt and sales cost influenced all of the technical, pure technical, and scale efficiency, while net profit influenced only the technical efficiency.
        4,800원
        6.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        KAFACI 회원국들의 농업은 아프리카 지역의 특성상 농업유형이 매우 다양하며, 회원국들간의 농업 생산성, 기술, 잠재력 등의 편차도 매우 크게 나타나고 있다. 이 논문에서는 KAFACI 사업을 대상으로 DAC가 제시한 개발(원조)사업 평가항목 중 적절성과 효율성을 중심으로 평가하였다. 이 사업의 적절성 평가결과 및 제고방안는 다음과 같다. 첫째,KAFACI 사업의 목표는 적절하게 수립되었으나, 비전 설정은재검토 될 필요성이 있다. 즉, 국격 제고는 이 사업의 간접적인 효과이므로 이 자체가 비전으로 설정되는 것 보다는 개도국의 기아 및 빈곤 퇴치를 비전으로 설정하고, 이를 위한 목표로서 다자간 농업협력을 강화하는 방향으로 수립될 필요성이 있다. 둘째, 이 사업의 대상은 아프리카 지역 국가의 농식품 기술 발전을 선도하기 위하여 우리나라 주도로 구축하는KAFACI에 참여의사를 밝힌 국가 중심으로 적합하게 선정되었다. 셋째, 이 사업은 본질적으로 아프리카 빈곤 해결을 위한농업기술 지원이라는 차원에서 출발하였기 때문에 이를 실현하기 위한 다양한 접근노력은 매우 높이 평가된다. 또한 이사업은 아프리카 대륙 전체적으로 그리고 사업에 참여하고 있는 각 나라들이 공통적으로 목표하고 있는 식량문제 해결에초점을 두고 있기 때문에 사업 대상국들의 개발 정책과 매우부합하다. 넷째, G20 정상회의 개최 및 DAC 가입 등 국제사회에서 한국의 역할 급부상 및 ODA 확대 요구가 점증하고있는 현실에서 MDGs 등 국제지원전략과의 부합성이 매우 높다. 다섯째, 이 사업은 ‘한-아프리카 개발협력 기본 구상’ 의구체적인 실천 사례로서 우리나라 정부의 대외 개발협력정책과 매우 부합하며, 개도국에 대한 기술원조 공여국으로서의 국격 제고에 기여하였고, 중장기적으로는 농식품산업의 국외 진출 및 시장 확대 효과가 매우 클 것으로 평가된다. 향후 적절성 제고 방안으로는 기존 아프리카 녹색혁명의 실패 요인을심도 있게 분석함과 동시에 새로운 아프리카 녹색혁명을 위한국제사회 노력에 부합하도록 하여야 한다. 이 사업의 효율성 평가결과 및 제고방안은 다음과 같다. 첫째, 국제 농업협력에 대한 중앙부처, KOTRA, ODA 사업을 검토한 결과 내역사업 단위에서 유사·중복성은 없었다. 이는그동안 농진청 중심으로 국제농업협력 사업이 추진되어 왔으며, 사업 추진을 위한 실질적인 전문성을 구비하고 있기 때문이다. 둘째, 한-아프리카 농식품기술협력협의체 사업의 추진주체는 농촌진흥청으로 명확하며, KAFACI 총회, 아프리카형 농업생산성 제고를 위한 사업, 회원국 확대 및 다자간 사업 확대 등 주요 추진사업 주체 또한 명확하기 때문에 관련 추진주체간의 협의·조정 여부도 효율적으로 추진되었다. 그러나 기존의 농촌진흥청 국제기술협력과 외에 2008년 국외농업팀의신설로 국제업무를 2개과에서 수행하고 있지만 실제 집행하는예산과 전문인력에 한계가 큰 것으로 나타났다. 셋째, 한-아프리카 농식품 기술협력 협의체(KAFACI)의 2011 세부업무 추진계획을 보면, 1) 조직기반 구축, 2) 총회 개최, 3) 국제기구와 공동 워크숍 개최, 4) 고위급 훈련과정 개최, 5) 개별 연수(OJT) 실시 6) 국가 프로젝트 협약 체결, 7) 신규 회원국 확보, 8) 예산 확보 등이었다. 그리고 이에 대한 평가 역시 신규회원국 및 예산 확보를 제외한 모든 사업이 계획대로 추진되었음을 알 수 있다. 향후 효율성 제고 방안으로는 서로를 알고 시작하는 ‘지피지기’전략 추진체계를 구축, 성과평가에 의한 지원시스템 구축, 타 개발협력기관과의 네트워크 강화 등에 주력해야 한다. 이와 함께 사업 평가를 위한 세부지표 및측정 방법론의 개발과 아울러 수원국의 주민, 전문가, 관련 공무원 등의 광범위한 설문조사 등의 필요성도 큰 것으로 제언되고 있다(Lee et al., 2010). 또한 단계별로 국제협력 조직·인력과 예산의 확대를 통한 지원체계 구축과 아울러 사업의안정성과 지속성 확보를 위한 법제화가 매우 중요하다 할 것이다.
        4,000원
        7.
        2009.05 구독 인증기관·개인회원 무료
        Subterranean termiteslive in the soil and wood that is in contact with soil. They have to discover food by constructing underground tunnel networks. Once the food is discovered and connected to the galleries, one important aspect of the foraging behavior is the food transfer by individual termites moving within the existing tunnels that lead to multiple existing food sources. In order to reveal how much the tunnel network is reliable to the food transfer efficiency, we used a lattice model suggested by Lee et al. (2006), which is capable of simulating the tunnel networks of Coptotermes formosanus and Riparius flavipes. After constructing the simulated tunnel networks, we randomly distributed food particles on the tunnel networks and then computed path entropy for the networksby selecting and evaluating the shortest paths from encountered food particles to the nest. The path entropy measured the degree of reliability of the networks for the food transfer entropy. Simulation results showed that path entropy between the simulated networks of C. formosanus and R. flavipes was significantly different due to the combinational effects of the network components such as the number of primary tunnels and the branching probability. We discussed the meaning of the results in relation to termite foraging efficiency.
        8.
        2018.09 KCI 등재 서비스 종료(열람 제한)
        Livestock manure treatments have become a more serious problem because massive environmental pollutions such as green and red tides caused by non-point pollution sources from livestock manures have emerged as a serious social issue. In addition, more food wastes are being produced due to population growth and increased income level. Since the London Convention has banned the ocean dumping of wastes, some other waste treatment methods for land disposal had to be developed and applied. At the same time, researches have been conducted to develop alternative energy sources from various types of wastes. As a result, anaerobic digestion as a waste treatment method has become an attractive solution. In this study has three objectives: first, to identify the physical properties of the mixture of livestock wastewater and food waste when combining food waste treatment with the conventional livestock manure treatment based on anaerobic mesophilic digestion; second, to find the ideal ratio of waste mixture that could maximize the collection efficiency of methane (CH4) from the anaerobic digestion process; and third, to promote CH4 production by comparing the biodegradability. As a result of comparing the reactors R1, R2, and R3, each containing a mixture of food waste and livestock manure at the ratio of 5:5, 7:3, and 3:7, respectively, R2 showed the optimum treatment efficiencies for the removal of Total Solids (TS) and Volatile Solids (VS), CH4 production, and biodegradability.
        9.
        2018.05 서비스 종료(열람 제한)
        국제적으로 런던협약에 의하여 2013년 이후 음폐수의 해양 투기가 금지되어 육상에서의 처리가 시급한 실정이다. 이에 따라 국내외에서 유기성 폐기물의 혐기성 소화를 통한 부피 저감과 에너지화에 대한 연구가 활발하게 진행되고 있다. 이에 대하여 독일 등 유럽국가와 중국 등이 유기성 폐기물을 이용한 혐기성 소화가 활발히 진행되어오고 있으며, 해외의 혐기성 공법으로 Dranco, Valorga, SEBAC, Schwarting 공법 등이 있다. 국내에는 이러한 공법을 기반으로 한 혐기성 소화시설이 적용되어 가동 중에 있으나 해외의 인정받은 공법 임에도 국내에 적용된 시설에서의 운전상의 미숙 문제나 유기성 폐기물 성상 차이에 의한 소화 효율의 저하 및 가동 중지 등 운전상에 문제가 발생하고 있어 국내 음폐수 특성에 맞는 공법과 운전 방법에 관한 연구가 필요하다. 이에 따라 본 연구에서는 음폐수의 처리에 대한 방안 마련을 위하여 혐기성 소화 공법 중 독일의 Schwarting 공법을 응용하였다. 기존 다공판이 설치된 내부 구조에 층 분리 효과를 더 강화하여 혐기성 소화를 촉진하고자 다공판을 추가하여 이중으로 엇갈린 다공판이 설치된 소화조를 설계하여 비교하는 실험을 진행하였다. 실험에 사용된 시료는 D시에서 발생되는 음폐수를 대상으로 하였으며, 혐기성 미생물의 식종은 D시의 혐기성 소화조의 미생물을 활용하여 독일의 Schwarting 공법이 응용된 공법의 효율성을 검토하고자 하였다.
        10.
        2017.11 서비스 종료(열람 제한)
        국내 하수처리장의 바이오가스화 시설은 낮은 농축율로 인한 저농도 유입수, 공정 흐름별 운영기술에 대한 노하우 부족 및 관리 미숙으로 인하여 혐기소화 효율이 미국 등 선진국 대비 약 54.2 %에 불과한 실정이다. 환경부는 바이오가스화 효율을 증진하고 하수슬러지를 바이오매스로 활용하기 위하여 2010년부터 전국적으로 에너지자립화 사업을 추진하였다. 특히 혐기소화조가 미설치된 하수처리장을 대상으로 음식물류폐기물과 병합소화시 연계 하수처리장의 유입 수질 등을 사전에 검토한 후 신규 소화조를 건설을 진행하고 있다. 하수슬러지 단독 및 병합처리 시설의 혐기소화조 내부 유출액에 대한 최우점 미생물 종을 분석하고 바이오가스화 시설의 주요 운전인자(유기물부하율, 메탄가스 발생량, C/N 비 등) 간의 정준상관분석을 실시하였다. 하수슬러지 단독 및 병합처리 시설의 상관관계 분포가 뚜렷이 구분되었으며, 메탄가스 생성율은 음폐수의 영향으로 VFAs, C/N비, VS/TS 등과 비례관계를 보임과 동시에 Mesotoga, Methanosaeta 미생물 군이 우점하는 경향을 보였다. 또한 하수슬러지 단독처리 바이오가스화 시설의 혐기소화조에서는 Copro-thermobacter, Methanosarcina 등의 미생물 분포가 높게 나타났다.
        11.
        2017.05 서비스 종료(열람 제한)
        하수슬러지, 음폐수, 가축분뇨 등의 유기성폐기물의 해양투기 금지와 육상처리에 대한 대책 마련이 시급해지면서 유기성폐기물을 통합소화하여 메탄 등의 신재생에너지를 생산할 수 있는 바이오가스화 기술이 대안으로 부각되고 있다. 국내에서 가동 중인 바이오가스화 시설 중 하수슬러지 혐기소화의 경우, 현행 법령에서 제시하는 유기물분해율과 메탄생성율 기준을 만족하지 못하고 있다. 또한 음식물류폐기물의 혐기소화는 다른 유기성 폐기물에 비하여 처리효율은 높으나 안정적인 시설 운영을 도모하기 어려운 실정이다. 본 연구에서는 12개소 하수슬러지 바이오가스화 시설을 대상으로 유기물 분해율, 메탄생성율을 산정하여 음식물류폐기물 투입 비율에 따른 영향을 평가하였다. 소화조 유입 및 유출수에 대한 TS, VS, 영양물질 (탄수화물, 단백질, 지방) 함량을 분석하여 이론적인 메탄생성율을 계산한 후 실제 현장에서 발생되는 메탄생성율과 비교하여 효율성을 판단하였다. 또한 사계절 정밀모니터링에서 도출된 휘발성지방산, 알칼리도, 암모니아성 질소 등 저해인자를 측정・분석하고 대상 바이오가스화 시설의 안정적 운전 여부를 진단하였다.
        12.
        2016.12 KCI 등재 서비스 종료(열람 제한)
        Livestock manure treatments have become a more serious problem because massive environmental pollutions such as green and red tides caused by non-point pollution sources from livestock manures have emerged as a serious social issue. In addition, more food wastes are being produced due to population growth and increased income level. Since the London Convention has banned the ocean dumping of wastes, some other waste treatment methods for land disposal had to be developed and applied. At the same time, researches have been conducted to develop alternative energy sources from various types of wastes. As a result, anaerobic digestion as a waste treatment method has become an attractive solution. In this study has three objectives: first, to identify the physical properties of the mixture of livestock wastewater and food waste when combining food waste treatment with the conventional livestock manure treatment based on anaerobic mesophilic digestion; second, to find the ideal ratio of waste mixture that could maximize the collection efficiency of methane (CH4) from the anaerobic digestion process; and third, to promote CH4 production by comparing the biodegradability. As a result of comparing the reactors R1, R2, and R3, each containing a mixture of food waste and livestock manure at the ratio of 5:5, 7:3, and 3:7, respectively, R2 showed the optimum treatment efficiencies for the removal of Total Solids (TS) and Volatile Solids (VS), CH4 production, and biodegradability.
        13.
        2016.09 KCI 등재 서비스 종료(열람 제한)
        Since 2013, due to the London Convention prohibiting marine dumping of waste, many problems have occurred because food waste generated every day must be handled on the ground. Owing to recent institutional efforts and various technical studies for eco-friendly food waste treatment, various methods of treating food waste using insects have been studied. However, efficiency of Korean food waste treatment is in fact known to be low due to the high salinity of Korean food waste. In this study, we evaluated the treatment efficiency of food waste with various salt and moisture contents by the black soldier fly (Hermetia illucens). The results showed that the moisture content does not affect food waste treatment efficiency by the black soldier fly and the decomposition ability of food waste is good even at salt contents as high as 3%.
        14.
        2015.05 서비스 종료(열람 제한)
        In this study, the experiment was carried out to produce methane by applying Semi-Continuous Leachate Recirculation Anaerobic Digestion System fed with source separated food waste from school cafeteria. There were two systems and each system consisted of a bioreactor and a leachate tank. Each bioreactor had a screen near the bottom of the reactor. 2L of Separated leachate was collected to the leachate tank each day by using a tubing pump and the leachate from the leachate tank was pumped to the bioreactor at the upper of the bioreactor. Through this circulation, the leachate having high concentration of VFAs was supplied to the bioreactor. At the beginning of the experiment, food waste/inoculum anaerobic sludge volume ratio was 2:8 that is 9g VS/L of OLR(Organic Loading Rate). Feeding was conducted every two weeks. Initial conditions of bioreactor was 30g VS/2・week and 33g VS/2・week were fed to bioreactor A and bioreactor B, respectively. Average biogas yields of the bioreactor were 0.723m³ Biogas/kg VS added in reactor A and 0.648m³ Biogas/kg VS added in reactor B.
        15.
        2014.10 KCI 등재 서비스 종료(열람 제한)
        In this study the effects of co-digestion of sewage sludge and food waste leachate on the anaerobic digestion efficiencyfrom sewage treatment facilities in S. Korea were investigated. For this study 15 facilities were selected including 9facilities treating sewage sludge only (S-Only) and 6 facilities treating sewage sludge and food waste leachate (S-MIX).The average volatile solid (VS) removal rate of S-Only was 30.7% and that of S-MIX was 45.2%. The COD removalrate of S-MIX (61.3%) was higher than that of S-Only (48.6%). It has been observed that the anaerobic digestion efficiencyof S-MIX was superior to that of S-Only because S-MIX contained more sufficient nutrient with higher VS contents andtotal solid (TS) contents emerging from food waste leachate. Therefore food waste leachate addition in sewage sludgeanaerobic digestion would be the preferred option to treat only sewage sludge.
        16.
        2006.06 KCI 등재 서비스 종료(열람 제한)
        Introduction : The obesity can be a serious problem that frequently induces a great deal of complications. Numerous methods have been applied to control obesity and one of them is aromatherapy. This study is a first attempt to verify the effect of the inhalation of essential oils on the obesity. This study was designed as the animal study, because the human study has many socio-psycho compounding variables. Methods : This study was designed to verify the effect of inhalation of essential oils on the body weight, feeding amount, food efficiency rate and serum leptin of SD rats. The research design is repeated measures over time, equivalent control group pretest-posttest experimental design. The subjects of this experiment were obese SD rats. They were allocated to one of four groups, the Fennel G., the Patchouli G., the Bergamot G. and control G. The experimental treatment was the inhalation of aromatherapy essential oils (Fennel, Patchouli, Bergamot). The experimental treatment was applied two times a day for 10 minutes each during 8 weeks. To evaluate the effect of inhalation of essential oils, the body weight, feeding amount and food efficiency rate was measured every week and serum leptin was measured before and after the experiment. The collected data was analyzed by repeated measures of ANOVA, Greenhouse-Geisser, ANOVA, Tukey, Kruskal Wallis test and χ²- test with SPSS program. Results : The results were as follows. The subjects of this study was 84 obese SD rats(40 males and 44 females). The means of age and body weight in obese SD rats were 30 weeks and 344.6g. The food efficiency rate was significantly lower in the Patchouli group and Fennel group than in Bergamot group and control group(P=.000). No significant group effects were found, but significant time effects were found for SD rat's body weight, feeding amount and serum leptin. Conclusions : In conclusion, these findings indicate that the inhalation of essential oils could be effective in lowering the food efficiency rate. 2)