• Title/Summary/Keyword: Improving the Performance

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Bitumen Emulsion Separation by Chemical Demulsification and Electrical Treatment (항유화제 및 전기장을 이용한 물/비튜멘 에멀전의 분리특성)

  • Kim, Sang Kyum;Yoon, Sung Min;Lee, Sang Hun;Bae, Wisup;Rhee, Young Woo
    • Clean Technology
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    • v.19 no.2
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    • pp.140-147
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    • 2013
  • In this study, chemical demulsification and electrical treatment methods were investigated for improving the efficiency of water separation from a water/bitumen emulsion. Two types of motor oils (GS Caltex, Deluxe Gold V 7.5 W/30 and, Hyundai gear oil 85 W/140) were used as model oils in basic experiments to investigate the effects of a demulsifier on water/oil emulsion separation. Chemical demulsifiers showing good water separation performance were then used in asphalt emulsion and bitumen emulsion separation trials. Maleic anhydride and e-caprolactam were shown to be good oil soluble demulsifiers and 2-ethylhexyl acrylate and acrylic acid were effective as water soluble demulsifiers. Based on the results obtained in basic experiments, these four demulsifiers were used in further asphalt emulsion experiments. The oil soluble demulsifiers showed higher water separation efficiencies than the water soluble demulsifiers. To investigate the water separation efficiency using a combined chemical and electrical treatment method, the water/bitumen emulsion was separated with the electrical oil treatment apparatus after a chemical demulsifier had been added to it.

Probiotic Properties of Enterococcus durans LP44 Isolated from Pigs Feces (돼지의 분변에서 분리한 Enterococcus durans LP44의 생균제로서의 특성)

  • 홍종욱;김인호;이상환;권오석;한영근;김지훈;강국희
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.5
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    • pp.939-944
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    • 2002
  • We have screened the microorganisms from pigs feces for the development of probiotics which have acid-and bile-tolerance. Among them, a strain which was identified as Enterococcu durans LP44 was selected. Sixty Duroc$\times$Yorkshire$\times$Landrace pigs (6.30$\pm$0.04 kg average initial body weight) were used in a 14 days growth assay to determine the effects of Enterococco duran Lf44 culture on growth performance of weaned pigs. Dietary treatments included 1) DF (dry feeding),2) W (wet feeding),3) WF+5ED (wet feeding+5% Enterocucu duran LP44 culture),4) WF+ 10ED (wet feeding +10% Enterococcus durans LP44 culture). For overall periods, average daily gain in pigs fed % diet tended to increase compared to pigs fed DF diet without significant difference. Also, there was no significant difference in gain/feed. At 5 days after the onset of the experiment, pigs fed WF+5ED and WF+10ED diets were significantly increased in dry matter and nitrogen digestibilities compared to pigs fed DF and W diets (p<0.05). At 14 days after the onset of the experiment, pigs fed WF+ 10ED diet were significantly increased in dry matter digestibility compared to pigs fed DF diet (p<0.05). Also, pigs fed WF + 10ED diet were significantly increased in nitrogen digestibility compared to other treatments (p<0.05). In conclusion, supplemental Enterococcus durans LP44 was an effective means of improving ADG and nutrient digestibility.

A Multi-sensor basedVery Short-term Rainfall Forecasting using Radar and Satellite Data - A Case Study of the Busan and Gyeongnam Extreme Rainfall in August, 2014- (레이더-위성자료 이용 다중센서 기반 초단기 강우예측 - 2014년 8월 부산·경남 폭우사례를 중심으로 -)

  • Jang, Sangmin;Park, Kyungwon;Yoon, Sunkwon
    • Korean Journal of Remote Sensing
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    • v.32 no.2
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    • pp.155-169
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    • 2016
  • In this study, we developed a multi-sensor blending short-term rainfall forecasting technique using radar and satellite data during extreme rainfall occurrences in Busan and Gyeongnam region in August 2014. The Tropical Z-R relationship ($Z=32R^{1.65}$) has applied as a optimal radar Z-R relation, which is confirmed that the accuracy is improved during 20mm/h heavy rainfall. In addition, the multi-sensor blending technique has applied using radar and COMS (Communication, Ocean and Meteorological Satellite) data for quantitative precipitation estimation. The very-short-term rainfall forecasting performance was improved in 60 mm/h or more of the strong heavy rainfall events by multi-sensor blending. AWS (Automatic Weather System) and MAPLE data were used for verification of rainfall prediction accuracy. The results have ensured about 50% or more in accuracy of heavy rainfall prediction for 1-hour before rainfall prediction, which are correlations of 10-minute lead time have 0.80 to 0.53, and root mean square errors have 3.99 mm/h to 6.43 mm/h. Through this study, utilizing of multi-sensor blending techniques using radar and satellite data are possible to provide that would be more reliable very-short-term rainfall forecasting data. Further we need ongoing case studies and prediction and estimation of quantitative precipitation by multi-sensor blending is required as well as improving the satellite rainfall estimation algorithm.

Long-Term Survival of Patients with Lung Cancer Treated by Traditional Korean Medicine Combined with Western Treatment: Report of Two Cases (양한방 복합투여로 장기간 생존을 보인 폐암 환자 2례)

  • Kang, Ji-young;Kim, Jun-young;Son, Chang-gue;Cho, Jung-hyo
    • The Journal of Internal Korean Medicine
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    • v.36 no.1
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    • pp.58-68
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    • 2015
  • Objectives : To evaluate the long-term survival effects of traditional Korean medicine (TKM) on refractory metastatic lung cancer and small cell lung cancer (SCLC), which have historically poor survival rates. Methods : A retrospective study was conducted using the medical records of two patients in Daejeon University hospital. The first patient, with SCLC, was treated from January 2000 to December 2009 and the other, with metastatic pulmonary cancer from primary hepatocellular carcinoma (HCC), was treated from September 2004 to February 2014. The patients were treated with herbal medicines at one-month intervals. During hospitalization, acupuncture and indirect moxibustion were performed concurrent with the administration of Western therapy. Treatment efficacy was assessed monthly using chest radiography, chest computed tomography, and laboratory examination data, and by measuring patient performance status. Results : Both patients exhibited a stable disease course for more than 9 years after the initial diagnosis of intractable lung cancer, suggesting that their disease status was controlled by TKM. Conclusions : We suggest that a combination of TKM with conventional Western therapy for refractory lung cancer patients is effective in controlling various symptoms related to lung cancer and improving quality of life, and may potentially prolong overall survival.

Numerical Analysis on Heat Gain of Liquid from Ambient Air with Various Fin Heights and Pitches of Fin-and-Tube Heat Exchanger in Hybrid Solar Collector (핀-튜브 열교환 구조를 갖는 복합집열기에서 핀 높이 및 간격에 따른 공기열 이용 액체 가열 성능에 관한 수치해석 연구)

  • Choi, Hwi-Ung;Fatkhur, Rokhman;Lyu, Nam-Jin;Yoon, Jung-In;Son, Chang-Hyo;Choi, Kwang-Hwan
    • Journal of the Korean Solar Energy Society
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    • v.36 no.3
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    • pp.53-61
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    • 2016
  • Solar assisted heat pump system uses solar thermal energy as a heat source of evaporator of heat pump. So, COP can be enhanced as well as collector efficiency. For improving performance of this system, some research about hybrid solar collector that has fin-and-tube heat exchanger has been conducted. This collector can get a thermal energy from ambient air for liquid heating, so heated liquid can be used as a heat source of evaporator in heat pump even the solar radiation is not enough. In this study, numerical analysis was conducted for confirming heat gain of liquid according to fin height and pitch of fin-and-tube heat exchanger in collector. As a result, higher heat gain was obtained on lower fin height and narrow fin pitch, but the pressure drop also increased with increment of heat gain. Thus the JF factor considering both heat transfer enhancement and pressure drop was investigated and the maximum value was shown when the fin height and pitch were 40mm and 45mm. So it is considered that this installation condition has a highest heat transfer improvement when comparing with pressure drop. However heat gain of liquid at this condition was less than the other installation conditions of fin pitch on same height. Then, after establishing a proper minimum heat gain of liquid, actual production and experiment of collector will be conducted with fin height and pitch showing maximum JF factor and satisfying selected minimum heat gain of liquid on the basis of results of this study.

An Empirical Assessment of Competency Requirements for Logistics Managers of Freight Forwarding Companies (복합운송주선업 물류관리자의 자격요건에 관한 연구)

  • Kim, Jin-Su;Hong, Eui
    • International Commerce and Information Review
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    • v.14 no.2
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    • pp.147-172
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    • 2012
  • The aim of this research is to identify the competencies required by freight forwarding company logistics managers or supply chain managers. And this research also attempts to show their relative importance and key knowledge areas that require improvement. Using a survey questionnaire, data was collected against forty three logistics and supply chain management skills or competencies, which were then grouped into four categories and analysed. The Analysis revealed that supply chain awareness, ability to make decisions, analytical skill, communication skill, supply chain cost, people skill, and integration of internal or external information flow which belong to logistics planning group are considered the most important competencies for effective and efficient logistics functioning. On the other hand, reverse logistics and IATA regulations from environmental awareness group show little influence on logistics managers for improving their logistics performances. The results have implications for a variety of parties including prospective logisticians, students, teachers and companies considering expanding their business to Chinese market. For example, the results permit companies to employ appropriate logistics managers who are qualified with sufficient skills and competencies suggested in this research. In the case of practitioners, the results provide a benchmark for comparison with their current level of abilities and suggested competencies.

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Improving Recall for Context-Sensitive Spelling Correction Rules using Conditional Probability Model with Dynamic Window Sizes (동적 윈도우를 갖는 조건부확률 모델을 이용한 한국어 문맥의존 철자오류 교정 규칙의 재현율 향상)

  • Choi, Hyunsoo;Kwon, Hyukchul;Yoon, Aesun
    • Journal of KIISE
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    • v.42 no.5
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    • pp.629-636
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    • 2015
  • The types of errors corrected by a Korean spelling and grammar checker can be classified into isolated-term spelling errors and context-sensitive spelling errors (CSSE). CSSEs are difficult to detect and to correct, since they are correct words when examined alone. Thus, they can be corrected only by considering the semantic and syntactic relations to their context. CSSEs, which are frequently made even by expert wiriters, significantly affect the reliability of spelling and grammar checkers. An existing Korean spelling and grammar checker developed by P University (KSGC 4.5) adopts hand-made correction rules for correcting CSSEs. The KSGC 4.5 is designed to obtain very high precision, which results in an extremely low recall. Our overall goal of previous works was to improve the recall without considerably lowering the precision, by generalizing CSSE correction rules that mainly depend on linguistic knowledge. A variety of rule-based methods has been proposed in previous works, and the best performance showed 95.19% of average precision and 37.56% of recall. This study thus proposes a statistics based method using a conditional probability model with dynamic window sizes. in order to further improve the recall. The proposed method obtained 97.23% of average precision and 50.50% of recall.

PBFiltering: An Energy Efficient Skyline Query Processing Method using Priority-based Bottom-up Filtering in Wireless Sensor Networks (PBFiltering: 무선 센서 네트워크에서 우선순위 기반 상향식 필터링을 이용한 에너지 효율적인 스카이라인 질의 처리 기법)

  • Seong, Dong-Ook;Park, Jun-Ho;Kim, Hak-Sin;Park, Hyoung-Soon;Roh, Kyu-Jong;Yeo, Myung-Ho;Yoo, Jae-Soo
    • Journal of KIISE:Databases
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    • v.36 no.6
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    • pp.476-485
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    • 2009
  • In sensor networks, many methods have been proposed to process in-network aggregation effectively. Unlike general aggregation queries, skyline query processing compares multi-dimensional data for the result. Therefore, it is very difficult to process the skyline queries in sensor networks. It is important to filter unnecessary data for energy-efficient skyline query processing. Existing approach like MFTAC restricts unnecessary data transitions by deploying filters to whole sensors. However, network lifetime is reduced by energy consumption for many false positive data and filters transmission. In this paper, we propose a bottom up filtering-based skyline query processing algorithm of in-network for reducing energy consumption by filters transmission and a PBFiltering technique for improving performance of filtering. The proposed algorithm creates the skyline filter table (SFT) in the data gathering process which sends from sensor nodes to the base station and filters out unnecessary transmissions using it. The experimental results show that our algorithm reduces false positives and improves the network lifetime over the existing method.

Current research trends in HACCP principles (HACCP의 연구동향)

  • Hwang, Tae-Young;Lee, Sun-Yong;Yoo, Jae-Weon;Kim, Dong-Ju;Lee, Je-Myung;Go, Ji-Hun;Kim, Myung-Ho
    • Food Science and Industry
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    • v.54 no.2
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    • pp.93-101
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    • 2021
  • Hazard Analysis Critical Control Point (HACCP) systems were developed to ensure a high level of food safety and reduced risk of foodborne illness. This paper focuses on significant issues associated with the implementation of HACCP; it provides an overview on recent literature. The structure of the paper follows six groupings of issues in the international literature of HACCP: (1) comparative studies and unification plan between HACCP and other food safety regulations; (2) verification of the HACCP system's effectiveness in improving food safety; (3) establishment of critical control point (CCP) for various foods HACCP model development; (4) expansion of HACCP application in the various fields and small businesses;(5) the impacts of HACCP on consumer's preferences and firms' financial performance in food industry; (6) HACCP and technological changes. The paper concludes with some suggestions for the future research in order to promote safe food supply chain for global customers.

Related Factors for Not Washing Hands at School among Adolescents (청소년의 학교 내 손씻기 미실천율과 관련요인)

  • SaGong, Hyo Jin;Lee, Yu-Mi;Choi, Eunsuk;Kim, Keonyeop
    • Journal of agricultural medicine and community health
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    • v.47 no.1
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    • pp.14-26
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    • 2022
  • Objectives: Handwashing is one of the most effective methods to prevent the spread of infectious diseases. This study assessed the related factors and reasons for not practicing handwashing at school among adolescents. Methods: We analyzed data collected from 57,303 adolescents who participated in the 15th Korea Youth Risk Behavior Survey 2019. Results: The proportions of not washing hands "before meals at school" and "after using the toilet at school" were 15.9% and 4.4%, respectively. The adjusted odds ratio for not washing hands before meals at school was significantly higher in girls (Odds Ratio [OR]=1.52, 95% Confidence Intervals [CI]=1.42-1.63), metropolitan city (OR=1.32, 95% CI=1.11-1.56), city (OR=1.29, 95% CI=1.08-1.54), higher grade, higher academic performance, lower economic status, not handwashing at home (OR=14.36, 95% CI=13.37-15.42), and without annual personal hygiene education (OR=1.41, 95% CI=1.33-1.49). Reasons for not washing hands at school among adolescents who do not wash their hands before meals at school included 'it is bothersome (52.3%)', 'there is no soap or hand sanitizer (13.8%)', and 'I do not feel the need (9.5%)'. Conclusions: Improving handwashing before meals at school among adolescents requires raising awareness of the importance of handwashing before meals and establishing a suitable environment and handwashing-encouraging culture.