• 제목/요약/키워드: Tightness

검색결과 438건 처리시간 0.028초

On the Conditon of Tightness for Fuzzy Random Variables

  • Joo, Sang-Yeol
    • 한국신뢰성학회:학술대회논문집
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    • 한국신뢰성학회 2002년도 정기학술대회
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    • pp.303-303
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    • 2002
  • We obtain the necessary and sufficient condition of tightness for a sequence of random variables in the space of fuzzy sets with compact support in R.

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고수압 조건에서의 세그먼트 방수성능평가에 대한 실험적 연구 (An experimental study for water tightness of segment under high water pressure)

  • 추석연;박영진;김동현;김용일;이두화;조상국
    • 한국터널지하공간학회 논문집
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    • 제5권4호
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    • pp.361-370
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    • 2003
  • 본 논문에서는 쉴드TBM터널의 세그먼트 연결부 방수재로 기장 많이 사용되는 수팽창성 지수재와 가스켓의 방수성능을 실험을 통하여 평가하였다. 방수성능은 내수압방식으로 수행하였으며, 수팽창성 지수재의 방수성능을 평가하기 위하여 5일간의 수침기간을 두었다. 수팽창성 지수재는 일반적인 형태와 비팽창성고무가 결합된 형태의 두가지 방식을 적용하였고, 가스켓은 일반적으로 가장 많이 사용되는 EPDM가스켓과 수팽창성지수재가 부착된 복합형 가스켓을 적용하였다. 세그먼트의 방수성능은 시공오차 및 세그먼트 변형에 크게 의존하며, 일반적으로 이러한 시공오차 및 세그먼트 변형은 연결부 벌어짐 (Gap)과 연결부 엇갈림 (Offset)으로 표현된다. 이 Gap과 Offset에 따른 방수성능의 변화를 관찰한 결과, 세그먼트의 방수성능은 시공오차 중 Gap의 영향을 크게 받는 것을 확인할 수 있었으며, Gap과 Offset에 대한 관리기준치가 제시되었다.

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콘크리트 진공튜브의 균열 발생에 따른 기밀성능 평가 실험 (An Experimental Test for Air-tightness Performance Evaluation of Cracked Concrete Vacuum Tube Structures)

  • 박주남;박형준
    • 대한토목학회논문집
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    • 제38권3호
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    • pp.377-385
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    • 2018
  • 튜브 내부의 공기저항을 최소화해 운송체의 빠른 이동을 가능하게 해주는 초고속 진공튜브 시스템(Super-speed vacuum tube system)은 고효율 친환경성으로 인해 차세대 운송시스템으로 주목받고 있다. 초고속 진공튜브 시스템은 외부에 비해 튜브 내부의 압력을 매우 낮게 유지할 필요가 있으므로 기밀성의 확보가 무엇보다 중요한 설계 요건이라 할 수 있다. 본 연구에서는 균열의 발생이 진공튜브 구조물 내부의 압력 변화에 어떠한 영향을 미치는지 고찰하기 위해 일련의 콘크리트 튜브 구조물에 대해 균열에 따른 내부 압력의 변화를 측정하는 실험을 실시하였다. 실험결과 균열의 길이 또는 균열폭에 대한 정보만으로는 시스템의 기밀성에 영향을 주는 균열의 성질을 표현하기에 부족한 것으로 나타났으며, 반면에 발생된 구조물의 변위와 등가투기계수와의 관계는 상대적으로 높은 상관관계를 가지는 것으로 나타났다. 이와 같은 실험 결과를 바탕으로 설계 단계에서 시스템의 기밀성을 예측하기 위한 향후 연구방향을 제시하였다.

Immediate Effects of Soft Tissue Massage on Posterior Shoulder Muscle Tightness: A Preliminary Study

  • Choi, Sil-Ah;Lee, Ji-Hyun;Yoon, Tae-Lim;Cynn, Heon-Seock
    • 한국전문물리치료학회지
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    • 제19권4호
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    • pp.8-15
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    • 2012
  • Posterior shoulder muscle tightness is frequently observed in shoulder impingement syndrome because tightness in the posterior portion of the shoulder muscles can cause anterior and superior translation of the humeral head in relation to the glenoid fossa. The purpose of this study was to determine the immediate effects of soft tissue massage on acromiohumeral distance (AHD), anterior translation of the humeral head, and glenohumeral (GH) range of motion (ROM) in subjects with posterior shoulder muscle tightness. Twenty-seven subjects with greater than $10^{\circ}$ difference in the range of GH horizontal adduction between right and left sides were recruited. The range of GH horizontal adduction and internal rotation were measured by a digital inclinometer. The AHD and anterior translation of the humeral head were measured using ultrasonography. A paired t-test was used to compare AHD, anterior translation of the humeral head, and the range of GH horizontal adduction and internal rotation before and after soft tissue massage. The results showed that AHD increased significantly (p<.05) and the anterior translation of humeral head decreased slightly, but not significantly (p=.40) after the soft tissue massage. Furthermore, the ROM of horizontal adduction and internal rotation in the GH joint increased significantly after the soft tissue massage (p<.05). These findings indicate that soft tissue massage on posterior shoulder muscle tightness is an effective method to increase AHD and ROM in the horizontal adduction and internal rotation of the GH joint.

GTX 차량기밀도 요구성능 도출에 관한 연구 (Study of the Air-tightness Requirement Decisions of GTX Trains)

  • 윤수환;조용현;홍석우
    • 한국철도학회논문집
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    • 제18권6호
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    • pp.513-521
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    • 2015
  • 수도권광역급행열차(GTX)가 대심도 지하터널을 180km/h로 운행하면, 작은 터널단면적으로 인해 터널 압력파에 의한 승객이명감이 문제될 것으로 예상된다. 이에 대한 대책으로 GTX의 적절한 기밀성능이 확보되어야 한다. 본 논문에서는 1D 전산해석을 수행하여 객실 압력변동 기준을 만족하는 차량기밀도를 도출하였다. A라인 37km 지하터널과 해당구간의 영업운행 상황을 모사하여 차량내부 압력변동을 예측하였다. 전산해석결과 이명감 방지를 위한 차량의 기밀도 요구성능은 복선구간에서 3초 이상, 단선구간에서 6초 이상으로 나타났다. 본 연구의 결과는 GTX 차량 제작 시 차체기밀도 요구성능 결정을 위한 유용한 자료로 활용될 수 있다.

Effect of High-frequency Diathermy on Hamstring Tightness

  • Kim, Ye Jin;Park, Joo-Hee;Kim, Ji-hyun;Moon, Gyeong Ah;Jeon, Hye-Seon
    • 한국전문물리치료학회지
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    • 제28권1호
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    • pp.65-71
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    • 2021
  • Background: The hamstring is a muscle that crosses two joints, that is the hip and knee, and its flexibility is an important indicator of physical health in its role in many activities of daily living such as sitting, walking, and running. Limited range of motion (ROM) due to hamstring tightness is strongly related to back pain and malfunction of the hip joint. High-frequency diathermy (HFD) therapy is known to be effective in relaxing the muscle and increasing ROM. Objects: To investigate the effects of HFD on active knee extension ROM and hamstring tone and stiffness in participants with hamstring tightness. Methods: Twenty-four participants with hamstring tightness were recruited, and the operational definition of hamstring tightness in this study was active knee extension ROM of below 160° at 90° hip flexion in the supine position. HFD was applied to the hamstring for 15 minutes using the WINBACK device. All participants were examined before and after the intervention, and the results were analyzed using a paired t-test. The outcome measures included knee extension ROM, the viscoelastic property of the hamstring, and peak torque for passive knee extension. Results: The active knee extension ROM significantly increased from 138.8° ± 9.9° (mean ± standard deviation) to 143.9° ± 10.4° after the intervention (p < 0.05), while viscoelastic property of the hamstring significantly decreased (p < 0.05). Also, the peak torque for knee extension significantly decreased (p < 0.05). Conclusion: Application of HFD for 15 minutes to tight hamstrings immediately improves the active ROM and reduces the tone, stiffness, and elasticity of the muscle. However, further experiments are required to examine the long-term effects of HFD on hamstring tightness including pain reduction, postural improvement around the pelvis and lower extremities, and enhanced functional movement.

피로와 가슴답답함(胸悶)을 주증으로 하는 전신성 홍반성 루푸스 환자에 대한 한의치료 1례 (A Case Report: Korean Medicine Treatment for a Systemic Lupus Erythematosus Patient Persistently Complaining of Fatigue and Chest Tightness)

  • 김민주
    • 대한한방내과학회지
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    • 제44권2호
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    • pp.117-128
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    • 2023
  • Objective: This study reported the improved symptoms of integrative Korean medicine-based treatment in a patient diagnosed with Systemic Lupus Erythematosus (SLE) who persistently complained of fatigue and chest tightness. Methods: A 51-year-old female SLE patient persistently complaining of fatigue and chest tightness underwent an 18-day treatment with Kracie Shihogayonggolmoryo-tang, Cheongpajeon-H, Gwanjeol-go, acupuncture, pharmacopuncture, cupping therapy, deep tissue meridian hot pack therapy, manual therapy, Interferential Current Therapy, and Extracorporeal Shock Wave Therapy. The Brief Fatigue Inventory (BFI) and Numeric Rating Scale (NRS) for each symptom were measured on admission, at one week, two weeks of hospitalization, and upon discharge. Clinical outcomes were assessed using these two figures. Results: After treatment, there was a reduction in the BFI score (7 to 3). The NRS score of chest tightness with hot flashes decreased from 8 to 5, neck pain lessened from 7 to 5, pain in both ankles diminished from 6 to 4, the cold hypersensitivity of both feet fell from 6 to 4, and heartburn decreased from 5 to 2. In order, the biggest clinical improvement was to heartburn, fatigue, and chest tightness with hot flashes. Conclusion: This case study shows that integrative Korean medicine-based treatment can improve symptoms of a Systemic Lupus Erythematosus patient persistently complaining of fatigue and chest tightness with hot flashes and suggests that Shihogayonggolmoryo-tang may be an effective option for managing and treating SLE patients.

연결고정, 인접면 접촉강도 및 치관길이에 따른 엔도포어 임플란트를 이용한 고정성 국소의치의 광탄성 응력 분석 (A PHOTOELASTIC STRESS ANALYSIS OF FIXED PARTIAL DENTURES WITH ENDOPOREIMPLANTS ACCORDING TO SPLINTING, CONTACT TIGHTNESS, AND CROWN LENGTH)

  • 정회열;최민호;김유리;조혜원
    • 대한치과보철학회지
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    • 제42권4호
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    • pp.425-442
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    • 2004
  • Statement of problem: A difficulty in achieving a passive-fitting prosthesis can be overcome by individual crown restoation of multiple implants. But individualized crown has another difficulty in control of contact tightness and stress distribution. Purpose: This in vitro study is to evaluate the stress distribution and the magnitude in the supporting tissues around Endopore implants with different crown lengths, interproximal contact tightness, and the splinting effects. Material & methods: Three Endopore implants($4.1{\times}9mm$) were placed in the mandibular posterior edentulous area distal to the canine and photoelastic model was made with PL-2 resin(Measurements Group, Raleigh, USA). Restorations were fabricated in two crown lengths: 9, 13 mm. For non-splinted restorations, individual crowns were fabricated on three custom-milled titanium abutments. After the units were cemented, 4 levels of interproximal contact tightness were evaluated: open, ideal($8{\mu}m$ shim stock drags without tearing), medium($40{\mu}m$), and heavy($80{\mu}m$). For splinted restorations, 3-unit fixed partial dentures were fabricated. This study was examined under simulated non-loaded and loaded conditions(6.8 kg). Photoelastic stress analysis was carried out to measure the fringe order around the implant supporting structure. Results: 1. When restorations were not splinted, the more interproximal contact tightness was increased among the three implants, the more stress was shown in the cervical region of each implant. When crown length was increased, stresses tended to increase in the apex of implants but there were little differences in stress fringes. 2. When nonsplinted restorations were loaded on the first or third implant, stresses were increased in the apex and cervical region of loaded implant. Regardless of interproximal contact tightness level, stresses were not distributed among the three implants. But with tighter interproximal contact, stresses were increased in the cervical region of loaded first or third implant. 3. When the nonsplinted restorations were not loaded, there were little stresses on the supporting structure of implants, but low level stresses were shown in the splinted restorations even after sectioning and soldering. 4. With splinted restorations, there were little differences in stresses between different crown lengths. When splinted restorations were loaded, stresses were increased slightly on the loaded implant, but relatively even stress distribution occurred among the three implants. Conclusions: Splinting the crowns of adjacent implants is recommended for Endopore implants under the overloading situation.

관절가동술과 스트레칭이 어깨후방뻣뻣함을 가진 충돌증후군의 어깨관절 근활성도와 안쪽돌림에 미치는 영향 (The Effects of Joint Mobilization and Stretching on the Muscle Activity and Internal Rotation of Shoulder Joint in Patients With Impingement Syndrome With Posterior Shoulder Tightness)

  • 문귀도;임진용;김태호;이동우
    • 한국전문물리치료학회지
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    • 제27권1호
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    • pp.38-44
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    • 2020
  • Background: Posterior shoulder tightness, which is a problem mainly seen in patients with shoulder impingement syndrome, disrupts the scapulohumeral rhythm between the humerus and scapulae. Objects: The aim of this study was to compare the effects of joint mobilization and stretching on shoulder muscle activity and internal rotation range of motion (ROM) of the glenohumeral joint in patients with impingement syndrome with posterior shoulder tightness. Methods: The research subjects included 22 in-patients with impingement syndrome with posterior shoulder tightness. They were randomly divided into two groups: one group (12 patients) was treated with joint mobilization and the other group (10 patients) was treated with stretching for the posterior shoulder tightness. Each treatment was performed five times a week for two weeks, and there were 15 sessions for each treatment. The ROM of the internal rotation and muscle activities of shoulder joint were evaluated pretest and posttest in each group. Electromyography data were collected from the upper, middle, and lower trapezius and serratus anterior during shoulder abduction of 90°, 120°, and 150°. Results: Both the joint mobilization and stretching groups showed significant decreases in muscle activity in the upper, middle, and lower trapezius on the posttest (p < 0.05). There was a significant difference in serratus anterior at 150° (p < 0.05), but there was no significant difference between group in post-hoc analysis (p > 0.025). The internal rotation ROM was significantly increased in the stretching group compared to that in the joint mobilization group (p < 0.025). Conclusion: This study found that both joint mobilization and stretching for posterior shoulder tightness were effective in muscle activity during arm abduction, also in order to increase internal rotation ROM of shoulder joint, stretching was effective in patients with impingement syndrome with posterior tightness.

의복의 구속성에 관한 연구(III) - 화운데이션의 의복압과 근활동과의 관계를 중심으로 - (Studied on Garment Restraint(III) - Relation between Clothing Pressure and Muscular Activity of Foundation -)

  • 심부자;최선희
    • 한국의류학회지
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    • 제17권2호
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    • pp.197-206
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    • 1993
  • We studied relation between the clothing pressure applied by foundations(waist nipper, girdle, body suit) on the waist of bodies and muscular activity, feeling of tightness. The main results were summerized as follows ; 1. Clothing pressure applied by foundations was high in order of girdle>waist nipper>body suit, also clothing pressure was higher back than front and side, sitting on the chair than standing posture, ventral flection than repose. Individual differences, even if size of body was equal, were shown in clothing pressure applied by foundations with subcutaneous fat's amount in measuring region. 2. The muscular activity of rectus abdominis than obliquus externus abdominis was more affected by foundations in all kinds of postures and motions. Amplitude of electromyogram was high sitting on the chair than standing posture, but there was little difference with motion variation. The wearing girdle strongly affected on the muscular activities of rectus abdominis and obliquus externus abdominis as compared with waist nipper and body suit. 3. The value for feeling of tightness by wearing waist nipper was higher than girdle and body suit. Also the case when sitting on the chair and ventral flection, the value for feeling of tightness was high. When the foundations were on the body, most tightened on the region of the body was anterior abdominal region.

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