• 한국식품영양학회지
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• 제22권2호
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• pp.286-292
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• 2009

This study was conducted to examine the effects of an 8-week weight loss program, on body composition, body shape satisfaction, body shape esteem in 15 obese children. This program included nutritional education and regular physical fitness. After completion of this program, height and body weight increased slightly but body compositions changed. BMI, degree of obesity, and body fat levels dropped slightly, however these differences were not significant. After the 8-week program body weight increased from $63.61{\pm}8.80\;kg$ to $64.07{\pm}9.11\;kg$, degree of obesity and BMI decreased from $151.73{\pm}13.62%$, and $29.08{\pm}2.35$ to $146.60{\pm}12.92%$, and $28.57{\pm}2.26$, respectively, and the percentage of body fat decreased slightly from $42.70{\pm}4.87%$ to $41.46{\pm}4.88%$. There were slight changes in weight of body muscle and lean body mass from $19.62{\pm}3.48\;kg$ and $36.17{\pm}5.78\;kg$ to $20.30{\pm}3.64\;kg$ and $37.16{\pm}6.18\;kg$, respectively. LBM and amount of muscle were higher after this weight loss program. The body shape esteem score increased from $7.60{\pm}4.01$ to $9.00{\pm}6.20$. There was no significant difference in body shape satisfaction before and after the program, and the participants also wanted to be leaner. Finally, body weight, BMI, and body fat showed negative correlations to body shape esteem.

• 한국가스학회지
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• 제17권1호
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• pp.1-6
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• 2013

$NO_x$ 배출허용기준이 강화되는 배출가스 규제에 대응하기 위한 대안으로서 제시되는 천연가스-수소 혼합연료 (HCNG)는 수소의 빠른 화염속도와 넓은 가연범위를 이용하여 후처리 장치 없이 규제치를 만족할 수 있어 디젤엔진에 비해 저공해성이나 가격경쟁력 측면에서 유리한 장점이 있다. 열효율 측면에서도 우수성을 인정받는 HCNG 연료는 수소 혼합율은 물론 운전영역별 운전전략에 따라 연소특성이 달라진다. 본 연구에서는 대형 천연가스 엔진에 수소혼합율 30%의 HCNG 연료를 적용하여 운전영역별 안정적인 연소특성 및 배출가스 특성을 살펴봄으로써 상용화 가능성과 운전전략을 포함한 기술 개발방향에 대해 검토하고자 하였다.

• 한국추진공학회지
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• 제19권4호
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• pp.37-44
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• 2015

정상초음파의 영향을 받는 메탄-공기 예혼합화염의 주파수-당량비 상관도 분석을 위한 실험적 연구가 수행되었다. 고속카메라를 이용하여 예혼합화염의 전파영상을 획득하였으며, 영상 후처리를 통해 화염전파속도와 함께 화염의 전파거동을 면밀히 관찰하였다. 이론당량비 이하의 연료희박 당량비 구간에서 정상초음파가 개재할 때, 연소반응 촉진으로 인해 화염전파속도는 증가하였으나 화학반응강도가 포화상태에 이르는 당량비에서는 그 속도가 감소하였다.

• 한국지구과학회지
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• 제25권8호
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• pp.739-747
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• 2004

본 연구에서는 유의미 학습을 촉진시키고 학습자들이 나름대로 개념을 형성하는 과정을 확인할 수 있는 방법인 개념도를 이용하여 중학생들의 ‘해수‘ 개념 형성에 미치는 영향에 대해 알아보았다. 이를 위하여 부산광역시의 중학교 1학년 4개 학급 128명을 대상으로 개념도를 활용한 수업 전-후에서 과학 학업 성취도와 자기 주도적 학습특성 및 개념도에 대한 인식을 조사해 본 결과는 다음과 같다. 첫째, 과학 학업 성취도에 미치는 효과는 유의수준 .05에서 유의미한 차이가 있는 것으로 나타났다. 둘째, 개념도를 활용한 수업은 전통적 수업 집단에 비해 학습자의 자기 주도적 학습특성을 향상시키는데 효과적인 것으로 나타났다. 셋째, 개념도를 활용한 수업이 개념 형성에 궁극적인 반응을 하는 것으로 나타났다.

• 대한기계학회논문집B
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• 제31권6호
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• pp.547-557
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• 2007

This study was conducted to investigate the flow and combustion characteristic of the experimental burner which was manufactured for the reflection of the oven and broil burner features. As slot shape, spacing between slots, and slot arrangement of the exit area which emits the mixing gas are different in case of oven burners and broil turners, the purpose of this study is to know the affection of the flame interaction and combustion characteristic according to the change of shape factors such as slot shape, slot arrangement, and slot-to-slot spacing. With no relation of the slot shape, as the spacing between slots became narrow, the occurrence of a lift-flame was delayed. So the combustion was possible in the leaner region, but the appearance of yellow-tip became a little fast. Slit slot port had the broadest operating range among the other slot shapes. Specially, from the side of lift-flame, as the jet that spreads downstream in the longitudinal slot was nearly circular just a few slot lengths away from the orifice, slot-to-slot spacing of the Slit port was closer than the other ports. These results could be expected through the computer numerical method and had a good agreement. As the spacing between slots increased, in case of Slit and Mix port, NOx emission rate was constant or decreased, but the NOx emission of Hole port was increased. CO emission rate of Slit and Hole port was increased as the slot-to-slot spacing was broadened.

• 한국의류학회지
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• 제19권3호
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• pp.397-415
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• 1995

The purpose of this study was to identify the change and characteristics of 20th men's fashion. The result of the Study as follows; 1 In the period 1890's-World War I there was a display of opulence and extravagance Therefore men's fashion pursued with elegance and grace. The rise of sports and an erosion of rules of Victorian society were evident influences before 1914. So men's silhouette resembled athletic appearance and less formality was shown in masculine attire. 2. During the period World War I-1920's the new equality of social relations between the sexes had an influence in fashion. Unisex look evolved so boyish shaped became the feminine ideal, men wanted to boyish fitted leaner stylings and natural shoulder suits. In the twenties youth, who seemed to have a social dominance, asserted their own testes in fashion. New style of men's fashion such as oxford bags and Ivy League Look appeared. After World War I "comfort" is the aim of fashion so casualness was reflected in fashion: vests often were discarded and man wore a soft, detachable collars. 3. In the thirties depression marked a shift in mood from gaiety and progressivism of the twenties to the conservative, even reactionary values. The role of men and women returned to more traditional attitudes, Every men's general appearance was bold and manly: his chest was broad and well-built, his shoulders square and muscular. The effects of World War ll were not on style but on textiles and clothing construction: lighter weight fabrics appeared and construction was simplified 4. Men's dress changed only in detail and not in essence. But there was a continued increase in the variety of clothes and color in men's fashion.

• 한국축산식품학회지
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• 제30권6호
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• pp.905-909
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• 2010

Two sets of data on carcass traits and beef cut parameters were used to investigate the relationships between carcass and beef cut measurements, which can be used to make predictions of retail cut percentages. One set had a total of 1,141 measurements of Hanwoo cattle of three different sex origins, which were slaughtered in an abattoir located at the National Institute of Animal Science, RDA, Korea from 1996 to 2008. To develop prediction models for retail cut percentage with higher accuracies than the current model, another set consisting of a total of 13,389 records of carcass and beef cut traits were collected from 30 abattoirs and butcheries in Korea from 2008 to 2009. Bulls yielded heavier and leaner carcasses than steers. High correlation coefficients were estimated between amount of body fat and percent retail cut (-0.82) as well as between back fat thickness (BF) and percent retail cut (-0.62). The amount of retail cut, however, was highly correlated with body weight before slaughter (BW, 0.95) or with cold carcass weight (CWT, 0.94). Relationships between percent retail cut and measurable beef yield traits, BF, loin eye area (LEA) or CWT varied by sex class, which must be considered for development of a prediction model with high accuracy. Models of data for all breeds and sexes fit the effects of breed, sex, and interaction of abattoir by butchers, whereas models of data for each breed and sex fit the effect of interaction of abattoir by butcher only. Due to possible future changes in back fat control, we performed a log transformation of BF. Our new models fit better than the currently used model.

• 대한기계학회논문집B
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• 제29권1호
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• pp.71-79
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• 2005

For the non-premixed interacting jet flames, it has been reported that if eight small nozzles are arranged along the circle of $40{\sim}72$ times the diameter of single jet, the flames are not extinguished even in 200m/s. In this research, experiments were extended to the partially premixed cases to reduce both flame temperature and NOx emission. Nine nozzles were used- eight was evenly located along the perimeter of the imaginary circle and one at the geometric centre. The space between nozzles, S, the equivalence ratio, ${\phi}$, the exit velocity and the role of the jet from the centre nozzle were considered. Normally, flame was lifted and flame base was located inside the imaginary circle made by the nozzle. As nozzles went away from each other, blowout velocity increased and then decreased. The maximum blowout velocity diminished with the addition of air to the fuel stream. When the fuel and/or oxidizer were not fed through the centre nozzle, the maximum blowout velocity obtained by varying S and ${\phi}$ was around 160m/s. Optimum nozzle separation distance at which peak blowout velocity obtained also decreased with ${\phi}$ decrease. Flame base became leaner as approaching to the blowout. It seemed that lots of air was supplied to the flame stabilizing region by the entrainment and partially premixing. To approve this idea and to enhance the blowout velocity, fuel was supplied to the centre region. With the small amount of fuel through the centre nozzle, partially premixed flame could be sustained till sonic velocities. It seemed that the stabilizing mechanism in partially premixed interacting flame was different from that of non-premixed case because one was stabilized by the fuel supply through the centre nozzle but the other destabilized.

• 대한가정학회지
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• 제50권8호
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• pp.79-95
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• 2012

The purpose of this study is to seek improvement in clothing life education through a development and application of the clothing life education program for middle schools based on the education and experience in arts & culture. On the basis of art & culture education as well as, Dewey's experience, the clothing life area education program was designed and developed for the 2nd year students in the middle school. This program was applied to 350 students of 9 2nd year classes in M middle school during the 17 periods of clothing life area classes, beginning from May 23rd, 2011 and lasting to September 30th, 2011. The leaner-evaluation was performed in terms of the level of learning interest and academic achievement. To measure the level of academic achievement, a mind-map evaluation was performed and a learning effect survey, which evaluates the level of achievement of learning objectives, was carried out. For the purpose of class observation, classes were filmed and analyzed. Characteristics of a class were recorded on a teacher's diary and was used to support the qualitative evaluation. According to the results, the education program is analyzed as being helpful and useful in student understanding of fiber, textile and, clothes, which are materials and outcomes of culture and art; moreover, they have a historical, cultural and artistic value in themselves. It is also analyzed as being helpful for the development of student aesthetic sensibility and emotion, for the construction of meaningful experience through a learning process, for the improvement of learning interest and the level of academic achievement, and for the positive recognition of the learning effect.

• 한국자동차공학회논문집
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• 제8권2호
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• pp.19-26
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• 2000

This paper presents the effects of initial pressure of mixture on CO, $CO_2$ and NOx emissions in constant volume combustion chamber. The CO, $CO_2,O_2,N_2$ concentrations in the chamber are determined by thermal conductivity detection (Gas-chromatograph) wile the NOx concentration is measured by chemiluminescent detection (NOx Analyser). Methane-air mixture is used as premixed fuel and the measurements are taken with equivalence ratios($\phi$) varing from 0.6 to 1.3, and initial pressures of methane-air mixture varing from 0.1MPa to 0.8MPa in constant volume combustion chamber. The NOx concentration steadily increases with increasing equivalence ratio, peaks in lean flame ($\phi$=0.85~0.9), and then rapidly decreases. However, as the initial pressure of mixture is increased, the equivalence ratio corresponding to the point of peak [NOx] shifts towards leaner conditions. This is caused by a similar shift in the peak [CH], which is caused by the variation with pressure and equivalence ratio of the rate of CH production from $CH_2$ and OH. The maximum combustion pressure peaks at $\phi$ =1.05 and the $CO_2$ concentration peaks at $\phi$=0.95~1.0 while the CO concentration rises sharply at the condition of fuel-rich mixtures. This is caused by complete combustion at $\phi$=0.95.