• The Korean Journal of Physiology
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• 제28권1호
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• pp.61-70
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• 1994

A new method is used to record the actual shortening produced during the auxotonic activity of the sartorius (SAR), gastrocnemius (CAS) and rectus abdominis (RAB) muscles of a lizard Uromastix. The auxotonic twitch and tetanus records thus obtained were used for the first time to calculate the coefficient of linear shortening (COLS). This coefficient represent the relative Index between change in length $(\Delta\;L=L_0-L_1)$ and tension $({\Delta}P\;P_0-P_1)$ due to shortening at the steepest rising phase of the twitch and tetanus, recorded at resting length. In addition to this, maximum shortening $(S_{max})$ and auxotonic tensions were also determined at resting lengths of these muscles. The COLS was found to express the speed of shortening and auxotonic tensions are suggested to be of value to express the internal architecture of SAR, GAS & RAB muscles. The results are discussed in terms of contractile and elastic elements of the muscles alongwith the importance of shortening at resting lengths in skeletal muscles.

• 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.

• 국제초고층학회논문집
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• 제6권1호
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• pp.91-99
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• 2017

Special consideration should be given to differential column shortening during the design and construction of a tall building to mitigate the adverse effects caused by such shortening. The effects of the outrigger - which is conventionally used to increase the lateral stiffness of a tall building - on the differential shortening are investigated in this study. Three analysis models, a constant-section, constant-stress, and general model, are prepared, and the differential shortenings of these models with and without the outrigger are compared. The effects of connection time, sectional area, and location of the outrigger on the differential shortening are studied. The sectional area of the outrigger shows a non-linear relation in reducing the maximum differential shortening. The optimum locations of the single and dual outriggers are investigated by an exhaustive search method, and it is confirmed that a global optimum location exists. This study shows that the outrigger can be utilized to reduce the differential shortening between the interior core wall and the perimeter columns as well as to reduce the lateral displacements due to wind or earthquake loads.

• 한국정보전자통신기술학회논문지
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• 제6권4호
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• pp.262-266
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• 2013

직교 주파수 분할 다중 (OFDM) 시스템에서는 채널의 지연확산 특성의해 발생하는 심볼간의 간섭 (ISI)을 제거하기 위해, 채널의 길이보다 길거나 같은 cyclic prefix (CP)를 삽입한다. 그러나 긴 CP는 전송률을 감소시 킨다는 단점이 있다. 대안으로, CP로 인한 성능 열화를 줄이기 위해 수신부에서는 channel shortening 필터를 이용하여 유효 채널의 길이를 줄이는 방법이 제안되어 왔다. 본 논문에서는 기존에 제안 된 채널 shortening 기 법인 minimum shortened signal to noise ratio (MSSNR), mimimum interblock interference (min-IBI)와 minimum intersymbol interference (min-ISI)을 비교분석한다.

• 한국식품조리과학회지
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• 제17권6호
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• pp.611-616
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• 2001

This study was carried out to investigate the effect of various lipids on the quality of Yackwa. Sesame oil, soybean oil, margarine for cream, margarine for pie and shortening were used as lipid for making dough of Yackwa in this study. The expansion rate of Yackwa ranked in the order of shortening, margarine for pie, soybean oil, margarine for cream and sesame oil. The Yackwa made with shortening showed low hardness, cohesiveness, gumminess and brittleness such as the ones made with sesame oil. The Yackwa made with sesame oil was oily and showed the lowest acceptability, but the Yackwa of shortening gained the highest score of acceptability in sensory evaluation. In conclusion. this experimental result indicated that shortening would be very useful as a substitute for sesame oil in making Yackwa.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1996년도 가을 학술발표회 논문집
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• pp.258-266
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• 1996

The purpose of this study is to make a reasonable correction in construction stage through exact prediction of long-time differential column shortening that occurs in the high-rise RC building. For this, a self-developed program adopted PCA code is used to predict differential column shortening with sequential loading process. Using this program, the amount of the different column shortening of Amatapura Apartment in Indonesia is predicted and the effect is analyzed. From the result, the major factor affecting the shortening amount in columns is elastic strain and the effect of shrinkage is very small rather than creep. And maximun differential column shortening is appeared near the middle of the building.

• 콘크리트학회논문집
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• 제16권1호
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• pp.36-42
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• 2004

철골철근콘크리트(SRC)가 초고층 건물에서 광범위하게 사용되고 있음에도 불구하고 SRC 구조부재에 대해 축소량 예측을 위한 도구는 철근콘크리트에 대한 재료적인 특성만으로 구성된 이론식을 적용하는 많은 문제를 안고 있다 따라서 본 연구는 초고층 건물의 기둥 축소량을 계산하는 기존의 방법에 대해 정확성을 평가하였다. 연구의 진행 방법은 다음과 같다. 우선 SRC 구조부재를 사용하여 만들어진 초고층 건물의 기둥축소에 대한 실측자료를 선정하였다. 다음으로는 전산해석 프로그램을 이용하여 SRC 구조부재에 대해 기둥 축소량을 계산하였다. 끝으로 측정자료와 해석자료를 비교하였다. 결론적으로 측정자료와 해석자료는 매우 근사한 차이를 나타냈다. 그러므로 기존의 방법은 SRC 구조부재를 사용하는 초고층 건물의 기둥 축소량을 평가하기 위해 사용되어도 될 것으로 사료된다.

• 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.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.490-495
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• 2006

The analysis method proposed by PCA is widely used in calculating the column shortening of reinforced and composite columns of a tall building. However, residual creep factor which relates creep strain of reinforced concrete to creep strain of plain concrete is based on Rate of Creep Method (RCM) which has theoretical defects and is considered obsolete. In this paper, a new equation for the residual creep factor based on Age-adjusted Effective Modulus Method (AEMM) which is considered exact and better than RCM is proposed. The residual creep factor by RCM is found to be higher than one by AEMM, which means current PCA method overestimates the shortening of a reinforced concrete column. By using the residual creep factor by AEMM, more exact column shortening of a tall building can be obtainable with a simple modification to PCA method.

• 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.