• 지질공학
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• 제24권3호
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• pp.311-322
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• 2014

Limestone bodies under the tectonic environment have experienced various tectonic processes, and also changed the stress state. In this study, calcite twins found in limestones of the Joseon Supergroup and Pyeongan Supergroup in the northeastern part of the Ogcheon Belt, South Korea were measured, then the paleostress (i.e., the maximum shortening axis) was reconstructed using the new calcite strain gauge (NCSG) technique. The average twin thickness and average twin intensity increase as the total twin strain increases. We utilize the appearance of twins, the average twin thickness and average twin intensity, and the total twin strain to estimate that the observed calcite twins were produced at temperatures of < $200^{\circ}C$ in the Joseon Supergroup and $170^{\circ}C$ in the Pyeongan Supergroup. In the Joseon Supergroup, the dominant direction of the maximum shortening axis WNW-ESE to NW-SE; NE-SW shortening is also observed. The maximum shortening axes in the Pyeongan Supergroup are oriented NW-SE and NE-SW. The NE-SW direction of maximum shortening is associated with the occurrence of the Songrim orogeny of the Paleozoic to Early Jurassic, and the NW-SE direction of maximum shortening correlates to the Daebo orogeny of the Early Jurassic to Late Jurassic. It is thus concluded that the paleostress across the study area changed from NE-SW to NW-SE during the Mesozoic.

• 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.

• 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.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회 논문집(I)
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• pp.397-402
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• 1998

The objectives of this paper are to estimate differential column Shortening and to determine appropreate compensation amount in 52 story Amatapura Apartment in Indonesia. for this, a computer program based on PCA and CEB-FIP code is developed. The results show that Elastic and Creep strain are the main factors of column shortening and the maximum differential shortening is appeared near the middle of the building height. The results between field survey and estimation have some difference, the most influential factor of the difference can be lateral restraints provided by horizontal members, which cannot be handled in this developed program. Hence introducing the modification factors from various field survey, this program can be used properly in design and construction procedures.

• 한국전산구조공학회논문집
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• 제35권2호
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• pp.119-129
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• 2022

초고층 건물에서 수평변위 제어와 수직부재에서 발생하는 부등축소에 대한 검토가 필수적이다. 이러한 부등축소는 비구조요소의 사용성과 구조요소의 안전성에 대해 문제를 야기할 수 있다. 따라서 이 연구에서는 120층 규모의 철근콘크리트 주거용 초고층 건물에 대해 시공단계해석을 수행하여 각 수직부재의 부등축소량을 비교하고 콘크리트의 장기거동의 영향을 분석하였다. 이를 위해 영향요인에 따라 축소량을 탄성축소량, 크리프축소량, 건조수축축소량으로 구분하여 검토하였으며 최대 절대축소량에 대한 지배적 요인을 분석하였다. 또한, 입주완료 후 30년에서 발생한 부등축소량에 대해 사용성 검토를 진행하였으며, 구조요소에 대해 설계단계와 시공단계의 부재력을 비교하여 분석하였다.

• 한국전문물리치료학회지
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• 제29권1호
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• pp.70-78
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• 2022

Background: Individuals with calf muscle shortening may have decreased dynamic balance. Objects: This study aimed to investigate the effect of mobilization with movement (MWM) and myofascial release (MFR) on kinematic changes in dynamic balance in individuals with calf muscle shortening. Methods: Thirteen participants were randomly assigned to the MWM or the mobilization with movement added myofascial release (MWM-MFR) group. The MWM group received treatment with only MWM, whereas the MWM-MFR group was treated with MWM and MFR. Pre- and post-intervention passive range of motion (PROM), maximum reaching lengths, and modified star excursion balance test (MSEBT) results were compared for all participants. Wilcoxon signed-rank test and Mann-Whitney U test were used for statistical analysis. Results: The results showed significant within-group differences in ankle PROM, but no significant between-group differences. The maximum reaching length in the MWM-MFR group in the posterolateral direction was significantly different before and after the intervention (p = 0.005). This group also showed significantly reduced ankle abduction in MSEBT during the posteromedial direction section 3 (p = 0.007) and posterolateral direction section 5 (p = 0.049) compared with the MWM group. Conclusion: Combined MWM and MFR intervention improves ankle stability in the coronal plane during the posteromedial and posterolateral forward movement in dynamic balance compared with only MWM in individuals with calf shortening.

• 상하수도학회지
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• 제24권2호
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• pp.203-210
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• 2010

The signification of calorie/water (C/W) ratio was investigated in the treatment of highly concentrated organic wastes by thermophilic oxic process (TOP). Swine waste was used in this study. When C/W ratio was 1.6, most of swine waste was decomposed and all water was evaporated in the 24-h injection cycle. To improve treatment efficiency of TOP treating swine waste, the effect of shortening the swine waste injection cycle was examined. The shortening of injection cycle was conducted to stimulate the activity of thermophilic bacteria. A high temperature in the reactor was maintained by shortening of the injection cycle. When the swine waste injection cycle was shortened, the C/W ratio was fixed at 1.6. As a result, by shortening the swine waste injection cycle from 24-h to 12 and 6-h, the maximum loading rate of swine waste per day could be improved 1.9 and 3.5 times, respectively.

• 약학회지
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• 제27권2호
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• pp.155-161
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• 1983

The rates of deterioration of contractile forces of isolated hearts from ginseng component treated rats were determined. Rat papillary muscles were also used to study the influence of ginseng on the mechanical performance of heart. Rats weighing 200-300g were administered orally with ginseng ethanol extract (100mg/kg/day), ginseng total saponin (50mg/kg/day) and ginsenoside Rbl (5mg/kg/ day) for a week respectively. The isolated hearts from rats were perfused with Krebs-Henseleit solution by Langendorff perfusion apparatus. The force-velocity relation was clearly seen with the load-generator equipped isotonic shortening recording apparatus. The control group was only able to maintain 60% of their initial contractile forces after 120 minutes of perfusion, whereas ginseng ethanol extract treated group was able to sustain nearly their initial strength even after 120 minutes of perfusion. The similar effects were seen in the hearts treated with total ginseng saponin and ginsenoside Rb$_{1}$. Ginseng ethanol extract did alter mechanical performance of rat ventricular myocardium. It increased both maximum velocity(Vmax) of isotonic shortening and isometric force (P$_{0}$) and showed increased velocity of shortening significantly (P<0,05) at any one afterload.d.

• 한국기후변화학회지
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• 제7권2호
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• pp.157-167
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• 2016

This study aims to evaluate the effect of shortened final cutting age by estimating future $CO_2$ absorption in each different scenarios based on each final cutting ages before and after shortening. We used $5^{th}$ Forest Type Map and Forest Yield Table to obtain information to estimate $CO_2$ absorption of forest. We also designed a simulated future scenarios from 2010 to 2100 which repeats cutting and reforestation according to respected each final cutting ages. As the result, number of cuttings and total amount of $CO_2$ absorption of forest were increased with shortened final ages. Total cutting times increased up to 2 in both minimum and maximum amount for Quescus spp. and Larix kaempferi. Maximum number of cutting of Pinus densiflora and minimum number of Pinus koraiensis increased by 1. Total $CO_2$ absorption increased 12％ for Quercus spp. which had the largest number of increase in cutting times, while total $CO_2$ absorption of Pinus koraiensis only increased by 1％. The result could be used to evaluate the changes in forest management plans and policies and then develop optimal final age for efficient sustainable forest management plans.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 춘계학술논문 발표대회
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• pp.147-150
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• 2007

As recent buildings often use low-quality concrete materials, are constructed defectively, and are put in extreme environmental conditions, many of them show the shortening of life resulting from the corrosion of reinforcing rods by salt damage, carbonization, freezing and thawing, cracking. This in turn raises the cost of repair and maintenance, so it is required to extend the life of structures through enhancing the durability of concrete. In response to the demand, researches on high-durability concrete are being made actively focused on the maximum water-cement ratio, the maximum unit quantity, the minimum cover thickness, the addition of mineral admixtures, etc. With this background, the present study examined the basic physical properties of concrete containing admixtures for enhancing the durability of concrete.