• 터널과지하공간
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• 제21권4호
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• pp.287-296
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• 2011

본 연구에서는 압축공기에너지 지하저장을 위한 복공식 암반공동의 기밀성능을 평가할 목적으로 다상유체 열유동 해석을 수행하였다. 기밀성능은 저장공동으로부터 누출되는 공기질량으로 평가하였으며, 저장공동 내부에 콘크리트 라이닝 기밀시스템을 설치하고 저장공동은 비교적 천심도인 지하 100m 심도에 위치하는 것으로 가정하였다. 저장공동 내 질량수지분석 결과, 콘크리트 라이닝 및 주변 암반의 투과계수가 누기량 및 저장공동의 장기적 기밀성능에 미치는 영향이 큰 것으로 파악되었으며 콘크리트 라이닝의 투과계수가 $1.0{\times}10^{-18}\;m^2$이하 일 경우, 저장공동 운영압력이 5 MPa에서 8 MPa 사이일 때 누기량은 1%이하 인 것으로 계산되었다. 또한, 콘크리트 라이닝의 초기포화도에 따른 공기누출량 계산결과, 라이닝 수분포화도를 증가시킬수록 누기량은 감소하고 저장공동 기밀성능이 향상됨을 확인하였다.

• 한국전문물리치료학회지
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• 제23권4호
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• pp.1-8
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• 2016

Background: Various methods are used for recovery of knee flexion range of motion (ROM) due to a tightened rectus femoris muscle (RFM) or limited inferior glide of the patella. Stretching methods are common interventions for restoring the tightened RFM length. Also patellar inferior gliding (PIG) technique can recover tightened RFM length too. However, effect of applying the PIG to passive knee flexion (PKF) has not been studied. Objects: The purpose of this study was to investigate the effect of combining PIG with RFM stretching for improving knee flexion ROM in subjects with RFM tightness. Methods: Twenty-six subjects with RFM tightness were recruited. Two different methods of knee stretching were tested: 1) PKF during modified Thomas test (MTT) and 2) PKF with PIG during MTT. The passive stretching forces was controlled by hand-held dynamometer. The knee flexion ROM angle was measured by a MTT with ImageJ software. Differences between the conditions with and without PIG were identified with a paired t-test. Results: The knee flexion ROM was significantly greater for PKF with PIG ($114.44{\pm}9.33$) than for PKF alone ($108.97{\pm}9.42$) (p<.001). Conclusion: A combination of passive knee flexion exercise and PIG can be more effective than PKF in increasing knee flexion ROM in individuals with RFM tightness.

• KIEAE Journal
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• 제17권4호
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• pp.59-65
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• 2017

Purpose: Thermal performance and air tightness of window are improved for the building energy efficiency. As the deteriorated houses are increased, the improve measures with low cost and easy installation are developed in the energy performance of window. Attached glazing and windbreak can be easily applied to the window with low cost. In this paper, the effect of the attached glazing and windbreak on the thermal performance and air tightness of window is analyzed as the measure to improve performance of window. Method: Thermal transmittance of glazing is evaluated through WINDOW simulation according to thickness of attached glazing and air cavity. Based on the simulation results, thermal transmittance, air tightness and condensation resistance performance of four cases are tested according to Korea standards. One type of PVC sliding double window is chosen as the specimen. For the analysis on low performance of window, the outside of window is excluded in the PVC sliding double window. Result: This study shows that thermal performance of glazing can be increased by the application of attached glazing. Furthermore, lower thermal performance of glazing can obtain the higher effect of attached glazing. The application of attached glazing and windbreak can effect on increasing thermal performance and air tightness of window.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.705-712
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• 2000

The fluid generally flows through fractures in crystalline rocks where most of underground storage facilities are constructed because of their low hydraulic conductivities. The fractured rock is better to be conceptualized with a discrete fracture concept, rather continuum approach. In the aspect of fluid flow in underground, the simultaneous flow of groundwater and gas should be considered in the cases of generation and leakage of gas in nuclear waste disposal facilities, air sparging process and soil vapor extraction for eliminating contaminants in soil or rock pore, and pneumatic fracturing for the improvement of permeability of rock mass. For the purpose of appropriate analysis of groundwater-gas flow, this study presents an unsteady-state multi-phase FEM fracture network simulator. Numerical simulation has been also conducted to investigate the hydraulic head distribution and air tightness around Ulsan LPG storage cavern. The recorded hydraulic head at the observation well Y was -5 to -10 m. From the results obtained by the developed model, it shows that the discrete fracture model yielded hydraulic head of -10 m, whereas great discrepancy with the field data was observed in the case of equivalent continuum modeling. The air tightness of individual fractures around cavern was examined according to two different operating pressures and as a result, only several numbers of fractures neighboring the cavern did not satisfy the criteria of air tightness at 882 kPa of cavern pressure. In the meantime, when operating pressure is 710.5 kPa, the most areas did not satisfy air tightness criteria. Finally, in the case of gas leaking from cavern to the surrounding rocks, the resulted hydraulic head and flowing pattern was changed and, therefore, gas was leaked out from the cavern ceiling and groundwater was flowed into the cavern through the walls.

• 대한정형도수물리치료학회지
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• 제12권2호
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• pp.11-20
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• 2006

Low back pain is often experienced by many people who are in an activity flag. Their work and daily life are affected by low back pain. There are many causes of low back pain. Among those many causes, this study was focused on a relation between low back pain and the tightness of iliopsoas. The study was implemented by measuring the angles of the hip joints in subjects consisting of a 30 patients group, who had been selected from the outpatients at the Median Hospital, and a 30 people control group from the outpatients at the M Hospital and employee of M hospital. The patients group consists of the patients with low back pain who have intermittently or continuously experienced low back pain within the last 6 months. The group also had no symptom of spondylolysis or spondylolithesis and no muscular abnormality in terms of pathology without any experience of disc or spine fusion operation. The control group consisted out of persons who had never experienced lower back pain and had never been subjected to physical therapy due to lower back pain. The hip joint angles of the subjects of this study were measured by means of the modified Thomas test position. Data was analysed by independent sampling t-test using SPSS 11.0. The following results were obtained: 1. The measured angles of patient's both hip joints were significantly smaller than the control group's. 2. In the males group, The angles of patients' both hip joints were smaller than the controls'. In the females group, The angles of patients' both hip joints were smaller than the controls'. In conclusion, this study demonstrates that there is a significant difference in the tightness of the iliopsoas muscles when comparing the patient group with the control group. We should therefore pay more attention in releasing the muscle tightness of iliopsoas muscles when performing physical therapy with patients with lower back pain.

• Journal of the Korean Wood Science and Technology
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• 제42권2호
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• pp.89-100
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• 2014

Energy consumption statistics in 2005 from the Korea Energy Management Corporation show that building energy usage was about 24.2% of total domestic energy consumption, and 64% of total building energy usage was consumed by residential buildings. Thus, about 10% of total domestic energy consumption is due to the heating of residential buildings. Building energy can be calculated by the configuration of the building envelope and the rate of infiltration (the volume of the infiltration of outdoor air and the leakage of indoor air), and by doing so, the annual energy usage for heating and cooling. Therefore, air-tightness is an important factor in building energy conservation. This investigate air infiltration and various factors that decrease it in timber frame buildings and suggest ways to improve air-tightness for several structural types. Timber frame buildings can be classified into light frame, post and beam, and log house. Post and beam includes Han-ok (a Korean traditional building). Six light frame buildings, three post and beam buildings, one Korean traditional Han-ok and a log house were selected as specimens. Blower door tests were performed following ASTM E779-03. The light frame buildings showed the highest air-tightness, followed by post and beam structures, and last, log houses.

• 한국생활과학회지
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• 제8권3호
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• pp.551-563
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• 1999

In this study, university students were allowed to wear the slacks varying the thigh circumference(slim/straight type) and crotch length(long, middle, short crotch type). Tightness and uncomfortability for each slacks were measured to be expressed 5point-likert type. The results can be summarized as follows: 1. At the research for measuring uncomfortability, measures of slim types and straight types of thigh circumference, crotch length B and C, and the body movement such as sitting down on the chair, sitting down with their body curling like a ball, and getting down on their knees were higher in slim types than in straight types. 2. Only crotch length C had different measures between these two types in tightness. 3. In uncomfortability, each of them had different measures among three kinds of crotch length and two types of thigh circumference had different measures among three kinds of crotch length. Four kinds of movement had different measures among three kinds of crotch length in uncomfortability. While uncomfortability of crotch length B was the highest one, that of crotch length A was the lowest one. 4. In tightness, each of them had different measures among three kinds of crotch length. While tightness of crotch length C was the highest one, that of crotch length A was the lowest one. Four kinds of movement had different measures among three kinds of crotch length in tightness.

• 한국철도학회논문집
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• 제14권2호
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• pp.151-159
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• 2011

본 논문에서는 시공이음 및 세그먼트 연결부 등 불연속 구간을 포함하고 있는 튜브 구조물에 대한 기밀성 평가를 위해 실험에 기초한 연구를 수행하였다. 실제 진공튜브 시스템을 위해 적용 가능한 콘크리트 라이닝을 최대한 모사할 수 있도록 콘크리트 관 1개로 구성된 일체형 튜브(N1) 1기, 동 콘크리트 관 두 개를 연결시킨 연결식 튜브 시험체(N2) 1기, 그리고 콘크리트 세그먼트형 튜브(S) 1기 등 총 3기의 시험체를 제작하여 각 시험체에 대해 내부 기압을 0.1atm로 낮춘 후 시간에 따른 내부 기압의 변화를 측정하였다. 기밀성 실험 결과 얻어진 흐름 곡선으로부터 시스템의 등가 투기계수를 산출하였는데 이음부가 많을수록 시스템의 등가투기계수는 높아지는 경향을 보였다. 또한 실험 결과를 바탕으로 가정된 튜브 단면 변화에 따른 기밀성의 민감도를 해석적으로 분석하였는데 튜브 구조물의 두께 및 직경이 커질수록 시스템 기밀성이 더 향상될 뿐 아니라 기밀성 보강의 효과가 더욱 커진다는 것을 알 수 있었다.

• 터널과지하공간
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• 제20권6호
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• pp.434-445
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• 2010

대용량 전력에너지저장시설로서의 복공식 압축공기 지하저장시설의 기밀시스템을 구성하는 콘크리트 라이닝 및 현장 타설 과정에서 발생하는 시공이음부의 투기특성을 파악하고자 콘크리트 블록시료를 이용한 모형실험을 수행하였다. 시공이음부의 투과계수는 콘크리트 블록보다 약 $10^1{\sim}10^4$ 배 정도의 투과성이 큰 것으로 파악되어, 현장 타설과정에서 시공이음부의 품질관리가 저장시설의 기밀성능 확보 관점에서 매우 중요함을 확인하였다. 또한, 접합면에 아크릴계 접착제를 타설함으로써 시공이음부의 투과계수를 콘크리트 블록 수준까지 감소시킬 수 있었으며 콘크리트 블록의 초기 수분함량이 높을수록 투과계수가 감소하여 기밀성능을 향상시킬 수 있음을 확인하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.390-391
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• 2009

Recently, composite hollow bushings have been increasingly employed mainly from the various characteristics. Composite bushings are superior to porcelain bushings in several respects, including lighter weight, better anti-pollution and anti-explosion properties, and easer manufacturing. This paper deals with the optimal thermal fitting for improved tightness characteristics of composite bushing. Two types of composite bushings were fabricated. For optimal fitting process, it is necessary using adhesive and designed internal structure of flange and FRP tube. In this study, for improved tightness characteristics of composite bushing has prominence and interface tolerance of flange and FRP tube. From FE-SEM analysis the adhesive layers were different with interface tolerance, sample 1 and 2 which have respective about $120{\mu}m$ and $50{\mu}m$.