• 한국자동차공학회논문집
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• 제19권3호
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• pp.23-28
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• 2011

To secure basic data for intake port design, effects of a port masking on the part load performance were investigated in a 4 valve SI engine. For this purpose, 9 kinds of masking, which have different shapes and masking ratio, are applied to the engine intake system. The characteristics of the performance were estimated through mixture response test at various engine load and speed. The results show that NOx emission, one of indexes for stratification, increases considerably in spite of retarded spark timing due to the stratification which is caused by unequal flow distribution between the two intake ports. The mechanism of stratification by masking is different from axial stratification and the fuel entering through masked port plays a very important role in this stratification process. In conclusion, the port masking method could be easily applied to engine intake system and be very effective for inducing the stratified charging without the change of port design.

• 한국환경과학회지
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• 제33권2호
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• pp.179-185
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• 2024

This study aimed to evaluate the differences in canine preferences for pet food terrine according to the processing method. As companion dogs, three male Spitz canines (average age 12 years, average weight 7 kg) and three male Spitz mix canines (average age 12 years, average weight 5 kg) were used in Experiment 1, whereas five male (average age 10 years, average weight 9 kg) and five female Shetland Sheepdogs (Sheltie, average age 10 years, average weight 8 kg) were used in Experiment 2, to evaluate their preferences and intake types. In both experiments, all dog categories mostly preferred 'meat' when it came to their first choice of food consumed, followed by 'vegetables', 'mixed eating', and 'vegetable leftover' last. This confirms means that canines are carnivores, and over time, choosing 'vegetables' or 'vegetable leftovers' as a secondary or alternate food source can be considered a natural process. When provided various terrines, canines in both experiments first ingested 'cooked' rather than 'freeze-dried' duck, chicken, beef, and pork terrines when selecting food at the start of feeding. For both experiments, most of the intake types using duck, chicken, beef, and pork terrine showed a preference for 'after consuming cooked terrine first and then intake freeze-dried' item. In conclusion, the reason for preferring cooked terrine can be attributed to the difference in the preparation cooking method of freeze-dried cooked terrine.

• 한국의사학회지
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• 제18권1호
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• pp.3-14
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• 2005

Among modern people's life-style, the lack of exercise and sleep is related to infertility. Underexercise accumulates damp-sputum, resulting in the insufficiency of essence. It also obstructs the creation of essence, leading to insufficient essence. Activities at night without sleep cannot create the condition to help the process of yin, causing the insufficiency of essence. Fast food is made from the cattle which are fed the feed containing growth hormone and antibiotics in large quantities. Growth hormone causes the process of yang excessively in human body, while antibiotic suppresses the process of yin, leading to excessive damp-heat and hyperactive ministerial fire. Antiseptic included in instant food hampers the process of fermentation, or yin, and inhibits the digestion mechanism, obstructing damp-heat and bringing about hyperactive ministerial fire. Intake of excessive flesh and meat gives rise to incomplete combustion and hinders the creation of essence, causing hyperactive ministerial fire due to the lack of yin. Milk suits the calf that has a rapid growth cycle. Milk intake by humans leads to the rapid process of yang and eventually hyperactivity of ministerial fire. The imbalance between yin and yang, with essence insufficent and ministerial fire hyperactive, causes infertility in three aspects. First, the lack of essence itself makes conception difficult. Secondly, damp-sputum resulting from ministerial fire obstructs the circulation of qi and blood. It also hampers the normal supply of qi and blood to the uterus. Thirdly, the excessive process of yang may result in infertility. Generally speaking, pregnancy starts with implantation. If the excessive process of yang is in progress in body, static condition needed for implantation cannot be maintained, leading to infertility.

• 에너지공학
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• 제14권2호
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• pp.73-81
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• 2005

강판의 냉간압연 후 소둔을 하기 위한 열처리 공정에서 사용되고 있는 Radiant Tube Burner(이하 RT버너) 연비를 개선하기 위한 효율적인 방법을 실험적으로 조사하였다. 재열기가 설치된 모델 RT버너를 실험에 맞도록 개조하여, 배기 중 산소 농도 조건을 변화시키면서 연료 소모에 대한 흡입공기의 온도와 산소분율의 영향도를 파악하였다. 본 연구의 결과, 흡기 온도를 상승시키면 RT버너의 chamber온도가 상승하나 그 상승폭은 흡기 온도 상승폭의 $10\%$에 지나지 많아, 흡입 공기 온도의 상승만으로는 연료 소모 개선을 기대할 수 없다는 것을 알 수 있었다 그러나, 흡입 공기 중 산소분율 변경 실험 결과, 흡입 공기 중의 산소분율을 $1.5\%$증가시키면 NOx의 배출이 약 $40\%$정도 증가하지만 약 $20\%$의 연비 개선 효과를 보였다. 따라서, NOx 배출 증가를 억제하는 산소 고부하 전용 RT버너는 RT버너 시스템의 연료 소모를 개선하는 효과적인 방법의 하나로 기대된다.

• 한국항공우주학회지
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• 제41권9호
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• pp.714-719
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• 2013

본 연구 대상 터보 프롭 항공기는 주어진 항공기 임무 수행을 위해 결빙 조건하에서도 운용이 가능하여야 한다. 동 연구에 적용된 터보 항공기의 공기 흡입구 계통은 정상 비행조건하에서 엔진 입구에 최대 전압력을 공급할 수 있도록 설계 및 검증이 되어야 할 뿐만 아니라 결빙조건하에서 생길 수 있는 얼음과 같은 입자가 엔진 흡입구 망으로 들어가서 엔진 화염꺼짐이나 엔진에 심각한 손상을 주지 않도록 하기 위한 관성분리기를 포함하도록 개발이 되어야 한다. 따라서 결빙 조건하에서 형상이 변하는 가변형상의 공기흡입구 조립체를 설계하고 설계 결과 확인을 위해 조립체에 대한 전산 유동 및 구조해석을 수행하였다. 이후 35% 축소형 모델을 제작하여 풍동시험을 수행하였다. 동 논문에서는 흡입구 조립체 개발과정에서 요구되는 공기역학적 설계, 잔산 유동/구조 해석 및 풍동 시험평가 결과를 기술하였다.

• 대한지역사회영양학회지
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• 제8권5호
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• pp.708-715
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• 2003

The purpose of this study was to investigate the status of recognition and intake of Saeng shik among housewives in Seoul, Busan, Daegu, Kwangju and Daejeon during February, 2002. Saeng shik is an uncooked freeze dried powdered food made from grains and vegetables. We interviewed 800 housewives, aged 30 to 49 years, living in urban areas. The survey was conducted using individual interviews on demographic characteristcs, status of recognition of Saeng shik, and the intake of Saeng shik. The data was analyzed using a SPSS program. The results were summarized as follows: Forty percentage of the subjects were well acquainted with Saeng shik. More than 60% of the subjects understood that Saeng shik is ‘the thing of grains and vegetables in the form of freeze-dried powder without heating process’. Saeng shik was taken by 16.9% of subjects. There was a significant regional and economic level difference in Saeng shik intake (p<0.05). Among the reasons given for Saeng shik intake, meal substitution ranked the highest. Other reasons were prevention of adult diseases, or it being a low calorie food. The survey questioned which the subjects considered before buying Saeng shik, taste, effect, constitution, sanitation and safety, satiety. ‘Taste’ ranked the highest. Among the subject who had experienced taking Saeng shik, 35.6% answered that they would continue taking Saeng shit. The reasons given for stopping taking Saeng shik included its high cost and taste. The subjects recognized it not only as a meal substitute, but also as a nutrient supplement. Based on these results on urban housewives' status of recognition of Saeng shik and their intake of it, more research is needed to improve Saeng shik.

• Journal of Radiation Protection and Research
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• 제34권3호
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• pp.129-136
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• 2009

국내 원전의 계획예방정비기간 중에 원자로계통의 개방과정에서 원자로건물내 공기 중으로 누설된 $^{131}I$의 체내 흡입으로 원전종사자의 내부피폭이 발생하였다. 이에 따라 원전에서 보유하고 있는 전신계측기(Whole body counter)를 이용하여 내부방사능을 측정하였다. 이들 측정값을 근거로 국제방사선방호위원회(ICRP)의 내부피폭 선량평가 지침을 적용하여 섭취량을 산정하고, 내부 피폭 방사선량을 평가하였다. $^{131}I$은 체내에서 섭취와 배설이 빠르고 갑상선으로 재축적이 일어나기 때문에 섭취 후 측정시점에 따라 섭취량이 차이를 보였다. 또한 ICRP 간행물에서 $^{131}I$의 전선에 대한 섭취잔류분율 자료를 제공하고 있지 않아 갑상선 섭취잔류분율 자료를 이용함으로써 섭취량 평가에서 오차를 나타내었다. 이에 따라 수계산과정으로 섭취량을 산정하고 예탁유효선량을 평가하였다. 한편 전선에 대한 섭취잔류분율을 새로 계산하였으며, 이 결과를 검증하였다. 또한 국제적으로 이용되고 있는 내부 피폭 선량평가 전신코드들 이용하여 섭취량 산정과 내부피폭 선량평가 평가결과에 대한 비교 계산이 병행하여 이루어졌다.

• 한국지역지리학회지
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• 제22권1호
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• pp.64-85
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• 2016

이 논문은 대구시 취수원 이전 계획을 둘러싼 대구와 구미 지역 간 갈등의 전개과정과 이를 해결하기 위한 민관협의회의 구성 및 운영 과정을 고찰하고자 한다. 이 논문은 우선 수자원이 자연적 순환과 사회적 순환 과정을 통해 유통되는 주요한 공공재 및 공유재이며, 따라서 이를 둘러싼 갈등은 이해당사자들이 모두 참여하는 협력적 거버넌스의 구축을 통해 해결되어야 한다고 주장한다. 특히 이 논문은 협력적 거버넌스가 규범적 목표 지향뿐만 아니라 전략적 수단으로 활용될 수 있음을 지적한다. 이러한 개념적 논의에 바탕을 두고, 이 논문은 대구시 취수원 이전 계획과 그 동안 갈등의 전개과정을 살펴본 후, 대구와 구미 지역 간 합의를 통해 구성된 민관협의회의 초기조건과 전개과정을 협력적 거버넌스의 관점에서 분석하고자 한다. 이 논문은 이 민관협의회가 현재 중단상태에 빠진 것은 협력적 거버넌스가 결국 규범적 목표 실현보다는 지역 헤게모니를 위한 전략적 수단으로 활용되었기 때문이라고 결론짓는다.

• 한국분무공학회지
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• 제6권1호
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• pp.25-34
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• 2001

Several efforts to meet the exhaust gas regulation have been undertaken by many researchers in recent years. Main researches are on development of design techniques of intake port and combustion chamber, atomisation of fuel and precise control of air-fuel ratio, post-treatment of exhaust gas and so on. Engine technology is changed from PFI to GDI to correspond with exhaust gas regulation. GDI technique makes it possible to preserve lean air-fuel ratio and control accurate air-fuel ratio. Nevertheless, It is not cleared that information of spray characteristics and atomization process are very dependent on fluctuation of pressure and change of temperature in intake stroke. In this study, a constant volume combustion chamber is manufactured to investigate various fluctuations of in-cylinder pressure for injection duration. It is taken photographs of injection process of conventional GDI injector using PMAS. Then, it was verified experimently that ambient conditions as temperature and pressure of combustion chamber have effects on process of spray growth and atomization of fuel.

• 한국농공학회지
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• 제20권1호
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• pp.4592-4598
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• 1978

The purpose of this research is to find out mathemetically an economical intake water depth in the design of head works through the derivation of some formulas. For the performance of the purpose the following formulas were found out for the design intake water depth in each flow type of intake sluice, such as overflow type and orifice type. (1) The conditional equations of !he economical intake water depth in .case that weir body is placed on permeable soil layer ; (a) in the overflow type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }+ { 1} over {2 } { Cp}_{3 }L(0.67 SQRT { q} -0.61) { ( { d}_{0 }+ { h}_{1 }+ { h}_{0 } )}^{- { 1} over {2 } }- { { { 3Q}_{1 } { p}_{5 } { h}_{1 } }^{- { 5} over {2 } } } over { { 2m}_{1 }(1-s) SQRT { 2gs} }+[ LEFT { b+ { 4C TIMES { 0.61}^{2 } } over {3(r-1) }+z( { d}_{0 }+ { h}_{0 } ) RIGHT } { p}_{1 }L+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 }L+ { dcp}_{3 }L+ { nkp}_{5 }+( { 2z}_{0 }+m )(1-s) { L}_{d } { p}_{7 } ] =0}}}} (b) in the orifice type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }+ { 1} over {2 } C { p}_{3 }L(0.67 SQRT { q} -0.61)}}}} {{{{ { ({d }_{0 }+ { h}_{1 }+ { h}_{0 } )}^{ - { 1} over {2 } }- { { 3Q}_{1 } { p}_{ 6} { { h}_{1 } }^{- { 5} over {2 } } } over { { 2m}_{ 2}m' SQRT { 2gs} }+[ LEFT { b+ { 4C TIMES { 0.61}^{2 } } over {3(r-1) }+z( { d}_{0 }+ { h}_{0 } ) RIGHT } { p}_{1 }L }}}} {{{{+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 } L+dC { p}_{4 }L+(2 { z}_{0 }+m )(1-s) { L}_{d } { p}_{7 }]=0 }}}} where, z=outer slope of weir body (value of cotangent), h1=intake water depth (m), L=total length of weir (m), C=Bligh's creep ratio, q=flood discharge overflowing weir crest per unit length of weir (m3/sec/m), d0=average height to intake sill elevation in weir (m), h0=freeboard of weir (m), Q1=design irrigation requirements (m3/sec), m1=coefficient of head loss (0.9∼0.95) s=(h1-h2)/h1, h2=flow water depth outside intake sluice gate (m), b=width of weir crest (m), r=specific weight of weir materials, d=depth of cutting along seepage length under the weir (m), n=number of side contraction, k=coefficient of side contraction loss (0.02∼0.04), m2=coefficient of discharge (0.7∼0.9) m'=h0/h1, h0=open height of gate (m), p1 and p4=unit price of weir body and of excavation of weir site, respectively (won/㎥), p2 and p3=unit price of construction form and of revetment for protection of downstream riverbed, respectively (won/㎡), p5 and p6=average cost per unit width of intake sluice including cost of intake canal having the same one as width of the sluice in case of overflow type and orifice type respectively (won/m), zo : inner slope of section area in intake canal from its beginning point to its changing point to ordinary flow section, m: coefficient concerning the mean width of intak canal site,a : freeboard of intake canal. (2) The conditional equations of the economical intake water depth in case that weir body is built on the foundation of rock bed ; (a) in the overflow type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }- { { { 3Q}_{1 } { p}_{5 } { h}_{1 } }^{- {5 } over {2 } } } over { { 2m}_{1 }(1-s) SQRT { 2gs} }+[ LEFT { b+z( { d}_{0 }+ { h}_{0 } )RIGHT } { p}_{1 }L+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 }L+ { nkp}_{5 }}}}} {{{{+( { 2z}_{0 }+m )(1-s) { L}_{d } { p}_{7 } ]=0 }}}} (b) in the orifice type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }- { { { 3Q}_{1 } { p}_{6 } { h}_{1 } }^{- {5 } over {2 } } } over { { 2m}_{2 }m' SQRT { 2gs} }+[ LEFT { b+z( { d}_{0 }+ { h}_{0 } )RIGHT } { p}_{1 }L+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 }L}}}} {{{{+( { 2z}_{0 }+m )(1-s) { L}_{d } { p}_{7 } ]=0}}}} The construction cost of weir cut-off and revetment on outside slope of leeve, and the damages suffered from inundation in upstream area were not included in the process of deriving the above conditional equations, but it is true that magnitude of intake water depth influences somewhat on the cost and damages. Therefore, in applying the above equations the fact that should not be over looked is that the design value of intake water depth to be adopted should not be more largely determined than the value of h1 satisfying the above formulas.