• 제목/요약/키워드: Tightness

검색결과 438건 처리시간 0.032초

Composite 부싱의 기밀 특성을 위한 최적의 압착에 관한 연구 (A Study on Optimal Fitting for Tightness Characteristics of Composite Bushing)

  • 조한구;강형경;유대훈
    • 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 $50{\mu}m$.

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중소도시 공동주택의 실내공기질(새집증후군) 실측에 관한 연구 (Field Measurements of Indoor Air Quality in Apartment Units at Medium-size Cities)

  • 윤재옥
    • KIEAE Journal
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    • 제10권4호
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    • pp.81-86
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    • 2010
  • The main sources of the new house syndrome(sometimes it called sick building syndrome) are a concentration of formaldehyde (HCHO) and a concentration of total volatile organic compounds(TVOC). I had field measurements of indoor air quality in the apartment unit at medium-size cities(Y city, C city). I measured indoor air temperature, HCHO concentration in 16 units, TVOC concentration in 6 units and air tightness in 7 units. And I measured outdoor air quality, HCHO concentration and TVOC concentration. Mean concentration of HCHO was $357{\mu}g/m^3$(2006 standard=$120{\mu}g/m^3$), mean concentration of TVOC was $3,092{\mu}g/m^3$ and mean effective air leakage area was 193 cm2. There was a close relation between the indoor air temperature and HCHO concentration, between the indoor air temperature and TVOC concentration. Air tightness also had relation.

봉사장력에 따른 본봉 Seam의 구조해석 (Analysis of the Structure of Lockstitched Seam according to Sewing Thread Tension)

  • 서정권
    • 한국의류산업학회지
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    • 제3권1호
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    • pp.25-30
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    • 2001
  • In order to investigate the influence of thread tension on the structure of lockstitch seam, stitch tightness and seam balance ratio are measured at various tensions of needle thread and bobbin thread. The structure of lockstitch was shown in terms of skeleton stitch models to obtain quantitative analysis of stitch tightness. The balanced seam formed to the rectangu1ar stitch model under low bobbin thread tension, but the fabric tightness produced by interlaced needle and bobbin thread under high bobbin thread tension. In this paper, new equation to obtain seam balance ratio was proposed for a lockstitch seam. By using the new equation, the seam balance ratio was not affected by the stitch density and fabric thickness. In order to form the balanced seam, the ratio on tension of needle thread and bobbin thread was about 6:1~7:1 in this experiment.

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A Note on the Invariance Principle for Associated Sequences

  • Kim, Tae-Sung;Han, Kwang-Hee
    • Journal of the Korean Statistical Society
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    • 제22권2호
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    • pp.353-359
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    • 1993
  • In this note we consider other type of tightness than that of Birkel (1988) and prove an invariance principle for nonstationary associated processes by an application of the central limit theorem of Cox and Grimmett (1984), thus avoiding the argument of uniform integrability. This result is an extension to the nonstationary case of an invariance priciple of Newman and Wright (1981) as well as an improvement of the central limit theorem of Cox and Grimmett (1984).

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SOME RESULTS ON CONVERGENCE IN DISTRIBUTION FOR FUZZY RANDOM SETS

  • JOO SANG YEOL;CHOI GYEONG SUK;KWON JOONG SUNG;KIM YUN KYONG
    • 대한수학회지
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    • 제42권1호
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    • pp.171-189
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    • 2005
  • In this paper, we first establish some characterization of tightness for a sequence of random elements taking values in the space of normal and upper-semicontinuous fuzzy sets with compact support in $R^P$. As a result, we give some sufficient conditions for a sequence of fuzzy random sets to converge in distribution.

고속전철의 기밀 거동 해석 (Analysis of the air tightness for high speed train)

  • 정병철;염경안;강석택
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2002년도 추계학술대회 논문집(I)
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    • pp.220-224
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    • 2002
  • As the train run through the tunnels, especially at high speed, pressure shock developed by the running train gives the influence on the pressure fluctuation inside the tunnel and consequently, inside the car. This pressure changes and pressure gradient is closely related with the tunnel section, train speed, air tightness of the train, length of the tunnel, etc. This study includes the analysis of the pressure behavior at the varied train speed and tunnel length. The results show that train speed affects the pressure gradient inside the car almost linearly, and that there exist the critical tunnel lengths that gives the maximum value of pressure change and pressure gradient, respectively.

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슬관절 손상으로 오인된 청소년 요추 추간판 탈출증 (Adolescent Lumbar Disc Herniation Misdiagnosed As Knee Injury)

  • 임재우;이태진;정현수;김학선
    • 대한정형외과스포츠의학회지
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    • 제11권1호
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    • pp.66-68
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    • 2012
  • 청소년에서 요추 추간판 탈출증은 드물게 발생하고, 임상적 증상이 성인과 달리 다양하게 나타난다. 또한, 청소년 환자의 주관적인 증상 호소를 분석하는 것이 어려워서 진단 및 치료가 늦어지는 경우가 많고, 성인에서와 달리 보존적 치료에 잘 반응하지 않는다. 슬괵근 강직 및 요추부 측만 변형등 청소년 요추 추간판 탈출증에서 특징적인 증상들은 수술로 잘 치료 되었고, 청소년의 추간판 부분절제술 수술 후의 중장기 추적검사에서 재수술 빈도는 15%로 성인과 큰 차이가 없었다. 그러므로, 보존적 치료에 잘 반응하지 않는 청소년 요추 추간판 탈출증은 수술적 치료를 적극적으로 고려해야 한다고 알려져 있다. 저자들은 축구를 하던 도중에 수상한 슬관절 손상으로 오인되어 수상 후 2년이 지나도록 진단이 지연되면서 슬괵근 강직과 보행 장애가 있었던 16세 청소년 요추 추간판 탈출증을 수술을 통해 치료하여 좋은 결과를 경험하였기에 문헌 고찰과 함께 보고하고자 한다.

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하악구치부에서 Bicon 임플란트에 의해 지지되는 고정성 국소의치의 광탄성 응력분석 (A PHOTOELASTIC STRESS ANALYSIS OF FIXED PARTIAL DENTURES WITH BICON IMPLANTS ON MANDIBULAR POSTERIOR AREA)

  • 강종운;김난영;김유리;조혜원
    • 대한치과보철학회지
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    • 제42권4호
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    • pp.412-424
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    • 2004
  • Statement of problem: Several prosthetic options are available for the restoration of multiple adjacent implants. A passively fitting prosthesis has been considered a prerequisite for the success and maintenance of osseointegration. Passivity is a particular concern with multiple implants because of documented inaccuracies in the casting and soldering process. One way to avoid this problem is to restore the implants individually, however, the restorations of individual adjacent impants requires careful adjustment of interproximal contacts. Purpose: The purpose of this study was to compare the stress distribution pattern and amount surrounding Bicon implants with individual crowns and splinted restorations. Material and method: A photoelastic model of a human partially edentulous left mandible with 3 Bicon implants($4{\times}11mm$) was fabricated. For non-splinted restorations, individual crowns were fabricated on 3 abutments ($4{\times}0.65mm,\;0^{\circ}$, 2.0 mm post, Bicon Inc., Boston, USA) 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($80{\mu}m$). Splinted 3-unit fixed partial dentures were fabricated and cemented to the model. Changes in stress distribution under simulated non-loaded and loaded conditions(7.5, 15, 30 lb) were analyzed with a circular polaricope. Results: 1. Stresses were distributed around the entire body of fin in Bicon implants. 2. Splinted restorations were useful for distribution of stress around implants especially with higher loads. 3. By increasing the contact tightness between the individually restored three implants, the stress increased in the coronal portion of implants. Conclusions: Ideal adjustment of the contact tightness was important to reduce the stresses around individually restored Bicon implants.

Comparison of the Duration of Maintained Calf Muscle Flexibility After Static Stretching, Eccentric Training on Stable Surface, and Eccentric Training on Unstable Surfaces in Young Adults With Calf Muscle Tightness

  • Jang, Hee-Jin;Kim, Suhn-Yeop;Jang, Hyun-Jeong
    • 한국전문물리치료학회지
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    • 제21권2호
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    • pp.57-66
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    • 2014
  • The objective of this study was to determine the duration of maintained calf muscle flexibility gained in young adults with calf muscle tightness, as measured by increases in ankle active and passive dorsiflexion range of motion (DFROM) after three stretching interventions. Twenty subjects (5 men and 15 women) with calf muscle tightness received the following three stretching interventions in one leg (assigned at random): static stretching (SS), eccentric training on stable surface (ETS), and eccentric training on unstable surfaces (ETU). The subjects received all three interventions to the same leg, applied in a random order. Each intervention had a break of at least 24 h in-between, in order to minimize any carryover effect. Each intervention used two types of stretching: with the calf muscle stretched and both knees straight, and with the knee slightly bent in order to maximize the activation of the soleus muscle. All three interventions were performed for 200 seconds. We measured the duration of maintained calf muscle flexibility through active and passive ankle DFROM before intervention, immediately after intervention (time 0), and then 3, 6, 9, 15, and 30 min after intervention. We found a difference in the duration of maintained calf muscle flexibility between the three interventions. In the ETS and ETU interventions, a significant improvement in calf muscle flexibility, both ankle active and passive dorsiflexion ranges of motion (ADFROM and PDFROM), was maintained for 30 min. In the SS intervention, however, ADFROM before 9 min and PDFROM before 6 min were statistically different from the baseline. Our results suggest that ETS and ETU may be more effective than SS for maintaining calf muscle flexibility in young adults.