• 제목/요약/키워드: In-Direct Feeding

검색결과 176건 처리시간 0.027초

수동급기 직접 메탄올 연료전지의 동적 모델 (Dynamic Model of a Passive Air-Breathing Direct Methanol Fuel Cell)

  • 하승범;장익황;차석원
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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    • pp.33-36
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    • 2008
  • The transient behavior of a passive air breathing direct methanol fuel cell (DMFC) operated on vapor-feeding mode is studied in this paper. It generally takes 30 minutes after starting for the cell response to come to its steady-state and the response is sometimes unstable. A mathematical dynamic one-dimensional model for simulating transient response of the DMFC is presented. In this model a DMFC is decomposed into its subsystems using lumped model and divided into five layers, namely the anodic diffusion layer, the anodic catalyst layer, the proton exchange membrane (PEM), the cathodic catalyst layer and the cathodic diffusion layer. All layers are considered to have finite thickness, and within every one of them a set of differential-algebraic governing equations are given to represent multi-components mass balance, such as methanol, water, oxygen and carbon dioxide, charge balance, the electrochemical reaction and mass transport phenomena. A one-dimensional, isothermal and mass transport model is developed that captures the coupling between water generation and transport, oxygen consumption and natural convection. The single cell is supplied by pure methanol vapor from a methanol reservoir at the anode, and the oxygen is supplied via natural air-breathing at the cathode. The water is not supplied from external source because the cell uses the water created at the cathode using water back diffusion through nafion membrane. As a result of simulation strong effects of water transport were found out. The model analysis provides several conclusions. The performance drop after peak point is caused by insufficiency of water at the anode. The excess water at the cathode makes performance recovery impossible. The undesired crossover of the reactant methanol through the PEM causes overpotential at the cathode and limits the feeding methanol concentration.

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Risk Factors of Breast Cancer among Women in Eastern India: A Tertiary Hospital Based Case Control Study

  • Das, Soumen;Sen, Santanu;Mukherjee, Anindya;Chakraborty, Debadatta;Mondal, Pankaj Kumar
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권10호
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    • pp.4979-4981
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    • 2012
  • Aim: Breast cancer is one of the most common cancers of women in India with high fatality rate. Over a 1 year study period 105 consecutive biopsy or fine needle aspiration cytology confirmed breast cancer patients were interviewed by direct questionnaire method regarding risk factors attending Surgery and Radiotherapy OPD of Medical College Kolkata, West Bengal while taking other 105 patients attending Surgery Department for some other disease as controls. The data were compiled in MS Excel 2007 and analyzed by Epi info 3.5.1 software. Among the cases, rural residence, illiteracy and low socio-economic status was significantly higher than controls. Late onset of menarche, late onset of menopause, ever OCP usage, breast feeding for 1-2 years and age of 1st childbirth between 20-30 years were found to be significant protective factors. People should be made aware regarding the modifiable risk factors to prevent breast cancer.

분사압력변화에 따른 액체 LPG 분무특성 -디젤분무와의 비교- (Liquid LPG Spray Characteristics With Injection Pressure Variation -Comparison with Diesel Spray-)

  • 임희성;박권하
    • 한국연소학회지
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    • 제4권2호
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    • pp.43-50
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    • 1999
  • Liquefied petroleum gas (LPG) has been used as motor fuel due to its low emissions and low cost. The fuel feeding system has been improved with stringent requirement for exhaust emissions. LPG carburetion system was first introduced, then the system has been changed to a precisely controlled gas injection system, but this gas feeding system has a limitation on improving power output. In order to improve an engine performance, a multi-point port injection system was introduced recently, and a liquid direct injection system into a cylinder was suggested as a next generation system to maximize a fuel economy as well as a power. This study addresses the analysis of the LPG spray from diesel injectors. The spray images are visualized and compared with diesel sprays in a wide injection pressure range. The photographs show much wider dispersion of LPG sprays.

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분사압력변화에 따른 액체 LPG 분무특성;디젤분무와의 비교 (Liquid LPG Spray Characteristics With Injection Pressure Variation;Comparison with Diesel Spray)

  • 임희성;박권하
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 1999년도 제19회 KOSCO SYMPOSIUM 논문집
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    • pp.21-26
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    • 1999
  • Liquefied petroleum gas(LPG) has been used as motor fuel due to its low emissions and low cost. The fuel feeding system has been improved with stringent requirement for exhaust emissions. LPG carburation system was firstly introduced, then the system changed into a gas injection system controlled precisely, but those gas feeding system has a limitation on improving power output. In order to improve an engine performance, a multi-point port injection system was introduced recently, and a liquid direct injection system into a cylinder was suggested as a next generation system to maximize a fuel economy as well as a power. This study addresses the analysis of the LPG spray from diesel injectors. The spray images are visualized and compared with diesel sprays in a wide injection pressure range. The photographs show much wider dispersion of LPG sprays.

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아버지의 영아 돌봄에 관한 문헌연구 (A Study of father's care giving in infancy)

  • 김영희
    • 부모자녀건강학회지
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    • 제1권
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    • pp.75-87
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    • 1998
  • These days social and economical changes have influence on the structure of family and the role of family members. Working mothers and widowers with children are increasing because of economical difficulties. Support from relatives are decreasing because of the conspicuous trend toward nuclear families. According to these reasons androgynous fathers are required. Today's fathers in Korea socially and culturally have learned about traditional parenting, but they are changing their fathering styles to meet the demands of the times. However they don't have their own fathering models. Therefore nurses who hold an advantageous position to teach and support from clinic have to encourage them to care their infants. The purposes of this study were to define father's care giving in infancy, understand influencing factors on fathering, and the differences between fathering and mothering, then contribute to nursing implementation for supporting fathers. This study was designed to review references about father's care giving. The results were follows: Six aspects of parent participation were direct care. indirect care, play, decision-making concerning the child, amount of time of sole responsibility for the child and overall availability to the child. Direct care involved feeding, bathing, going to child if child awakens. dressing, putting child to bed, taking child to doctor, nurse, or dentist, transporting child to and from sitter, day care, or school, washing child's hair. Indirect care involved cleaning up after child, preparing child's food, fixing child's broken playthings, washing child's clothes, arranging baby-sitting, shopping for child's toys and clothes, transporting baby-sitter to and from your home. Young fathers were gradually participating in direct care like feeding, taking child to doctor. Father's care giving stimulated mothering and promoted parent-infant relationship. Influencing factors of fathering would be divided into father characteristics, surrounding factors, infant attributes. Father characteristics were age, role perception, relationship with parent. Surrounding factors were the opportunity of early contact, support system, spouse's expectation, marital adjustment, feeding type, past experience of care giving. Infant attributes were temperament, behavior, age, sex. The differences between fathering and mothering were reviewed. Fathers were poor at care giving. but their caring was similar to mother's. This subtle difference positively worked upon infant's growth and development. On the basis of these theoretical data, nurses can empower fathers to cooperate with mothers in caring infants.

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신생아의 TPN 요법 시 발생되는 Cholestasis 치료를 위한 Ursodeoxycholic Acid의 약물사용 평가 (Drug Evaluation of Ursodeoxycholic Acid Use for Treatment of Cholestasis Associated with TPN Therapy in Neonate)

  • 이정옥;송태범;이명구;임성실
    • 약학회지
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    • 제54권4호
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    • pp.270-281
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    • 2010
  • Total parenteral nutrition (TPN) is necessary to neonates in neonatal intensive care unit (NICU) for survival and growth because of impossible of enteral feeding. Long-term TPN can be associated with a broad spectrum of hepatobiliary disorder, ranging from mild hepatic dysfunction to severe end-stage liver disease. Cholestasis developed most commonly in neonate, ursodeoxycholic acid (UDCA) is widely used in adult with cholestatic and non-cholestatic liver diseases but there have been limited data on the effects in neonate with PNAC. This study was performed retrospectively to review all medical histories of the total 30 neonates with was administrated UDCA for treatment to parenteral nutrition associated cholestasis (PNAC) at Chungbuk National University Hospital NICU from April 2002 to December 2008. UDCA was administrated at bilirubin is over 2 mg/dl. The criterias for drug evaluation were included hepatic biochemical marker such as direct bilirubin, total bilirubin, AST, ALT, ALP and GGT, TPN therapy period, cholestasis development period, UDCA treatment period, UDCA dosage and adverse effect. In the results, Post-UDCA treatment significant was decreased direct bilirubin, total bilirubin, AST and ALP (p<0.05), and was decreased GGT (p>0.05) and slightly was increased ALT (p>0.05). Reffective timect biDCA was appear at mean $10.5{\pm}1.3$ days, iDCA administration period was mean $64.4{\pm}5.9$ days, cholestasis period was mean $71.9{\pm}6.4$ days and UDCA dosage was mean $22.9{\pm}0.9$ mg/kg/day. Common adverse effects is diarrhea, 5 patients arised mild diarrhea but it possible also related with increased enteral feeding. In conclusion, iDCA can decrease direct bilirubin that major parameter t bcholestasis and oher hepatic biochemical makers. UDCA is effective on PNAC without any serious side effect and cost-effective. Although no greatly shortening cholestasis period, but can protect to develop into severe liver disease and other complication or death. Based on these result, UDCA is recommended for treatment of cholestasis at direct bilirubin is over 2 mg/dl.

Thoroughbred 육성마의 방목과 사사기간 중 혈청 비타민 E, 미량광물질 및 기타 화학치의 변화 (Changes in Serum Vitamin E and Trace Mineral Levels and Other Blood parameters in Growing Thoroughbred Horses During the Period of Pasture Grazing and stable Feeding)

  • 이종언;박남건;진신흠;김영진;강동희;김규일
    • Journal of Animal Science and Technology
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    • 제44권6호
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    • pp.719-726
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    • 2002
  • 본 연구는 Thoroughbred 육성마에서 계절별 사양체계에 따른 혈청 비타민 E, 미량광물질 수준 및 혈액 화학치의 변화를 측정하기 위하여 수행되었다. 사사기간(이른 봄) 동안 50두의 육성마(암, 11${\sim}$14개월령)에게 농후사료(체중의 1.4%), 오챠드그라스 건초(0.62%)와 알팔파 건초(0.37%)를 급여하였다. 방목기간 동안 봄부터 초여름까지는 농후사료를 체중의 1.1% 보충급여 하였고 이 후 가을철 방목종료까지는 농후사료 1.1%와 알팔파 건초 0.5%를 급여하였다. 혈액을 이른 봄(사사기), 이른 여름 및 늦가을 (방목기) 3회에 걸쳐 채취하였다. 방목사양은 혈청 비타민 E, 혈중 요소(BUN), GOT, GTP, T-bilirubin 및 D-bilirubin 함량을 증가 시켰다 (P<0.01). 혈청 Fe 및 Zn 함량은 가을 방목사양에서가 다른 사양체계에서 보다 높게 (P<0.01) 나타났다. Cu는 방목기간에 비해 사사기간 동안에 높았다(P<0.01). 혈중 glucose 및 creatinine 함량은 방목기간에 비해 사사기간에 높게 (P< 0.01) 나타났다. 본 연구결과 말 혈청 비타민 E 및 미량광물질 함량과 각종 혈액 화학치는 사양체계 및 급여사료에 큰 차이가 있음을 보여 주었다. 따라서 비타민이나 미량광물질의 추가 공급은 계절별 사양체계 또는 급여되고 있는 사료내 함량 및 이용성 등을 고려하여 이루어져야 할 것으로 사료된다.

보리새우의 섭이와 성장 (Studies on Feeding and Growth of the Oriental Brown Shrimp, Penaeus japonicus Bate)

  • 최상
    • 한국수산과학회지
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    • 제3권3호
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    • pp.161-171
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    • 1970
  • 보리새우(Penaeus japonicus Bate)의 섭이량, 주간, 야간 섭이율과 일간 섭이율, 이료의 종류에 따른 섭이률의 차이, 보리새우의 성장과 이료의 전환효율등에 관해서 시험한 결과를 요약하면 다음과 같다. 1. 보리새우의 섭이율은 수온범위 $19\~30^{\circ}C$, 체중범위 $1.6\~14.9g$에서 수온이 높을수록, 또 새우의 크기가 작을수록 커지며, 평균 일간 섭이율은 $18\~44\%$에 달한다. 2. 항상 야간 섭이율이 주간 섭이율보다 크나, 무저질, 암상태 또는 직접광선을 피한 사육상태에서는 주간에도 일간 섭이률의 $22\~37\%$의 섭이를 이룩할 수가 있어, 그만큼 보리새우의 성장을 촉진시킬 수가 있었다. 3. 멸치와 바지락의 두가지 이료에서는 주야의 구별없이 멸치를 한층 더 많이 섭취하였으며, 일간 섭이율중에서 멸치 및 바지락육의 섭이율은 각각 $12.9\%$, $10.3\%$이었다. 4. 보리새우의 체중(W;g)과 일간 성장률 ($DGR;\%$) 사이에는 log DGR=0.7035-0.7864 logW의 관계식이 성립되고, 새우의 크기에 비예하여 일간 성장율은 작아진다. 5. 보리새우의 이료의 전환효율은 새우의 크기에 따라 큰 차이가 없이 평균 $2.8\~7.8\%$의 범위로 변동하며, 지금까지 알려진 어류 (문치가재미, 고등어, 방어 등)와 참오징어의 그것에 비교하면 매우 작은 값을 취한다.

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Ionotropic Receptor 76b Is Required for Gustatory Aversion to Excessive Na+ in Drosophila

  • Lee, Min Jung;Sung, Ha Yeon;Jo, HyunJi;Kim, Hyung-Wook;Choi, Min Sung;Kwon, Jae Young;Kang, KyeongJin
    • Molecules and Cells
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    • 제40권10호
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    • pp.787-795
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    • 2017
  • Avoiding ingestion of excessively salty food is essential for cation homeostasis that underlies various physiological processes in organisms. The molecular and cellular basis of the aversive salt taste, however, remains elusive. Through a behavioral reverse genetic screening, we discover that feeding suppression by $Na^+$-rich food requires Ionotropic Receptor 76b (Ir76b) in Drosophila labellar gustatory receptor neurons (GRNs). Concentrated sodium solutions with various anions caused feeding suppression dependent on Ir76b. Feeding aversion to caffeine and high concentrations of divalent cations and sorbitol was unimpaired in Ir76b-deficient animals, indicating sensory specificity of Ir76b-dependent $Na^+$ detection and the irrelevance of hyperosmolarity-driven mechanosensation to Ir76b-mediated feeding aversion. Ir76b-dependent $Na^+$-sensing GRNs in both L- and s-bristles are required for repulsion as opposed to the previous report where the L-bristle GRNs direct only low-$Na^+$ attraction. Our work extends the physiological implications of Ir76b from low-$Na^+$ attraction to high-$Na^+$ aversion, prompting further investigation of the physiological mechanisms that modulate two competing components of $Na^+$-evoked gustation coded in heterogeneous Ir76b-positive GRNs.

Experience of Seventeen Compact Wet End Systems

  • Meinander, Paul-Olof
    • 펄프종이기술
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    • 제34권5호
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    • pp.70-76
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    • 2002
  • Ten years ago most papermakers were convinced that a system needs to be voluminous and heavy for controllability and stability. In order to improve grade changing dynamics, the author of this paper began developing a compact papermachine wet end. The results have proven that compactness is beneficial even more broadly. Quoting Voith$^1$the trend is now the opposite - the systematic collecting and direct feeding of the individual water flows back into the system". In its gasless form this is actually covered by a POM Technology Patent.tent.