• 한국운동역학회지
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• 제24권1호
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• pp.1-9
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• 2014

The purpose of this study was to investigate the muscle mechanical properties of the pelvic axial pre-rotational movement for the Jireugi in the Taekwondo Juchumseogi stance. Eleven elite Taekwondo Poomsae athletes participated. Each participant performed 5 right hand Jireugi in Juchumseogi stance as fast and strong as possible while their motion was recorded by a 3D motion analysis system and the ground reaction forces by two force plates. The power and work of the muscular group surrounding the waist were analyzed to verify the effect of the stretch-shortening cycle (SSC) theory. The cause of the greater power seems to be the application of the SSC by the muscles surrounding the waist during the preparation phase of the pre-rotation group. For the none pre-rotation group, they only used the concentric contraction of the muscles surrounding the waist. Because the pre-rotation group used the SSC theory, they had the effect of shortening of the range of movement, creating a fast and more powerful rotation, thus anticipating the increase the magnitude of impact.

• Nutrition Research and Practice
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• 제3권2호
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• pp.102-107
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• 2009

Fish oil and shortening have been suggested to have opposite effects on cardiovascular disease (CVD). This study investigated the effect of shortening and fish oil on CVD risk factors and aorta histopathology, and the association between risk factors and aorta histopathology. Male Wister rats (n=30) were fed an AIN-93G diet containing 20% fat in the form of fish oil, shortening, or soybean oil for 4 weeks. Total cholesterol (TC), triacylglyceride (TG), and C-reactive protein levels were significantly (P<0.001) lower in the fish oil than in soybean oil and shortening groups. HDL-cholesterol concentrations were significantly different (P<0.001) between groups. In addition, LDL-cholesterol levels were significantly (P<0.001) lower in the fish oil and shortening groups than in the soybean oil group. Insulin and glucose concentrations did not differ among groups. Effect of dietary fat on tissue fatty acid composition significantly differed in abdominal fat and brain compared with RBC, heart, kidney and liver. The aortic wall was significantly (P=0.02) thinner in the fish oil group than in the soybean oil and shortening groups. The aortic wall thickness was positively correlated with TG and TC, but negatively with EPA + DHA levels of all tissues. These results suggested that fish oil had protective effects on aorta histopathology by hypolipidemic action in this rat model.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1993년도 봄 학술발표회 논문집
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• pp.142-147
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• 1993

In the reinforced concrete structure, as the height of building structure increases, the accurate estimation of differential column shortening is important factor in the structural design. In this study, the analysis of column shortening is applied to 36-story building structure to be built in time. As a result, it may found that, as the difference of compressive stress become larger, differential shortening effect due to creep and shrinkage are more signicant factor to structural designer.

• Advances in concrete construction
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• 제5권2호
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• pp.155-171
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• 2017

The phenomenon of concrete column shortening has been widely acknowledged since it first became apparent in the 1960s. Axial column shortening is due to the combined effect of elastic and inelastic deformations, shrinkage and creep. This study aims to investigate the effects of ambient temperature, relative humidity, cement hardening speed and aggregate type on concrete column shortening. The investigation was conducted using a column shortening prediction model which is underpinned by the Eurocode 2. Critical analysis and evaluation of the results showed that the concrete aggregate types used in the concrete have significant impact on column shortening. Generally, aggregates with higher moduli of elasticity hold the best results in terms of shortening. Cement type used is another significant factor, as using slow hardening cement gives better results compared to rapid hardening cement. This study also showed that environmental factors, namely, ambient temperature and relative humidity have less impact on column shortening.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 2부
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• pp.67-70
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• 2011

The effect of column shortening is a major consideration in design and construction of tall buildings, especially in concrete and composite structural systems. To avoid unexpected demage in structural and nonstructural elements, differential shortening between vertical members resulting from differing stress levels, loading histories, volume-to-surface ratios and other factors in a high-rise building must be properly considered in the design process. This paper represents analyzed and measured shortening results of RC cores and columns at the 72 story Haeundae I'Park. It shows that WACS program based on ACI and PCA material model is effective for the prediction of column shortening.

• 한국식품영양과학회지
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• 제29권2호
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• pp.231-234
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• 2000

시판 탕수육을 대두유와 shortening으로 연속적으로 사용하여 튀긴 후 탕수육의 이화학적 및 관능적 변화와 튀김유의 이화학적 변화를 측정하여 이를 통한 한계 사용 횟수를 예측하고자 하였다. 튀김유의 TBA값은 대두유가 shortening보다 사용횟수에 따른 증가가 뚜렷하였으나, 탕수육의 경우에는 반대로 shortening을 사용한 탕수육이 대두유로 튀긴 탕수육보다 증가율이 높게 나타났다. 튀김횟수 증가에 따른 튀김유의 산가와 과산화물가는 증가하였으며 shortening에서 과산화물가의 변화가 크게 나타났다. 대두유로 튀긴 탕수육의 TBA값과 가장 상관 관계가 높은 풍미를 선정하여 한계사용횟수를 구한 결과 약 9회로 나타났고, shortening으로 튀긴 탕수육의 TEA 값과 가장 상관관계가 높은 인자인 조직감을 선정하여 한계 사용횟수를 측정한 결과 약8회로 나타났다. 대우유와 shortening의 한계사용횟수를 예측하기 위해 식품공전에 규정된 산가를 회귀방정식에 대입한 결과 두 기름 모두 약 8회로 나타나 위의 결과와 비슷한 한계사용횟수를 나타났다.

• 한국식품과학회지
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• 제13권1호
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• pp.74-89
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• 1981

Breadmaking is a complex system in which many variables govern the production of acceptable bread. Lipids, a minor component of wheat flour, function importantly in bread-making. Shortening, or fat, is one of the essential ingredients in commercial baking. Beneficial shortening effect depends on type and quantity of lipids present in wheat flour and also on wheat flour quality. Surfactants have been used in baking industry during last decade because certrain surfactants can replace shortening and/or natural flour lipids. A proper combination of lipidshortening-surfactant is more useful in the production of specialty breads such as whole wheat breads, high protein breads, high fiber breads or even non-wheat composite breads rather than in the production of regular white breads. This presentation is a review of recent studies on the contribution of flour lipids, shortening, and surfactants, alone or in combination in the production of breads; illustrations are mainly from data obtained in the author's laboratory.

• 대한수의학회지
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• 제43권1호
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• pp.31-39
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• 2003

We have investigated the effect of extracellular $Mg^{2+}$ ($[Mg^2+]_o$) on action potential duration (APD) in guinea pig papillary muscles by using microelectrodes. Increasing $[Mg^2+]_o$ resulted in progressive negative inotropic effect, progressive ascending depolarization of membrane potential, and increase in intracellular $Mg^{2+}$ concentration. In addition, increase in $[Mg^2+]_o$ from 1.1 to 3, 6, 10, and 20 mM produced a reversible dose-dependent shortening of both APD at 30% ($APD_{30}$) and 90% repolarization ($APD_{90}$), especially showing a tendency towards more remarkable prominent shortening in $APD_{30}$ than $APD_{90}$. Cooling from 37 to 33 and $27^{\circ}C$ diminished the $[Mg^2+]_o$-induced APD shortening. Increase in extracellular $Ca^{2+}$ concentration from 1.8 to 3.6 and 5.4 mM caused a significant depressed effect on the increasing $[Mg^2+]_o$-induced APD shortening. Furthermore, increase in $[Mg^2+]_o$ from 1.1 to 10 and 20 mM produced a significant depressed effect on the APD shortening induced by extracellular $Ca^{2+}$. Pretreatment of verapamil and imipramine significantly attenuated the increasing $[Mg^2+]_o$-induced APD shortening in both $APD_{30}$ and $APD_{90}$, whereas the $[Mg^2+]_o$-induced APD shortening was not affected by strophanthidin, glibenclamide and tetrabutylammonium. These findings suggest that the effects of $[Mg^2+]_o$ on APD are probably due to a decrease in ionic transport across plasma membrane. In conclusion, the present study indicates that $[Mg^2+]_o$ exerts antiarrhythmic activities by antagonistic actions on intracellular $Ca^{2+}$.

• 한국임상수의학회지
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• 제15권1호
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• pp.94-99
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• 1998

This study was carried out to determine the effects of uterus shortening on the duration required for estrus, the number of ovulation and the level of serum progesterone and prostaglandin $F_{2}{\alpha} (PGF_{2}{\alpha} $). The duration required for estrus after the surgical shortening of uterine horns and the interval between the following estrus was not affected by the surgical treatment but affected by luteal and follicular phase. The number of ovulations were increased by induction of superovulation to gilts with shortened uterine horns compared to the control. Serum progesterone concentration during the luteal phase was higher than that during the follicular phase with no difference between the control and me horns than that of the control. Findings of this study indicate that luteal formation and regressions and estrus cycle were normal when the unconnected parts of uterine horns were left in abdominal cavity. Therefore surgical shortening of uterine horns of sows helps embryo collections by non-surgical methods.

• 한국공간구조학회논문집
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• 제10권1호
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• pp.75-84
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• 2010

CIT 기둥의 장기거동에 관한 기존의 연구과 실험자료에 의하면 크리프 및 건조수축계수는 외부 강관의 구속효과에 의하여 철근콘크리트 기둥보다 작은 값을 가진다. 본 연구에서는 불확실성이 큰 콘크리트 강도와 특정크리프값과 작용하중을 매개변수로 하여 37층 건물의 CFT 기둥에 대한 확률론적 해석을 수행하였으며 매개변수의 특성을 분석하고 CFT 기둥의 축소량 해석값의 예측범위를 정량화하였다. 본 논문에서는 CFT 기둥축소량의 확률론적 해석을 위한 몬테카를로 (Monte Carlo) 기법을 소개하며 다중매개변수를 동시에 적용하여 매개변수의 변동에 따른 축소량의 영향을 분석하고 신뢰지수별 변동폭을 산정하였다.