• 제목/요약/키워드: gap joint

검색결과 254건 처리시간 0.03초

창호 시공용 폴리우레탄 및 실리콘 실란트 접착성 및 상응성 평가 (The evaluation for adhesion and compatibility properties of polyurethane and silicone sealant for window installation)

  • 안명수;정진영;서연원;김성현;배기선
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2014년도 추계 학술논문 발표대회
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    • pp.75-77
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    • 2014
  • Using sealant for window installation is sealing the gap between the window frame and outer wall (such as concrete). A sealant serves to prevent external environmental impacts such as moisture, rain, sand, and dust entering inside of the building and make the building durable. In order to fulfill basic jointing function of sealing, at least 6 mm joint gap between two bonding surfaces are required. Also, adhesion performance between sealant and surfaces and the compatibility with other building materials are required to check before installation. In general, 2 part polyurethane sealant and 1 part silicone sealant are most common materials for sealing the joint of window. In this study, adhesion performances of those two generic sealants reflecting actual application conditions and the compatibility evaluations with other building materials are conducted to propose proper window installation procedures.

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동축 파이프 이음부의 레이저용접 공정변수에 관한 연구 (Study on the Process Parameters for Laser Welding of Coaxial Circular Pipe Inner Flange)

  • 김용;박기영;이경돈
    • 한국레이저가공학회지
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    • 제12권3호
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    • pp.14-17
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    • 2009
  • The laser welding was performed for the flange joint of two overlapped coaxial circular pipes which serve as the inlet and connector pipes of STS 316L. The laser welding test finally resulted in a good penetration depth of 1.8 to 2.0 mm. On the way to get the good welding quality, two important parameters were found to be optimized. One is the focal positioning which is the offset of the laser beam focus to the exact welding seam line, which is more critical in the inner flange laser welding. When the beam spot size was deviated more than $200\;{\mu}m$ from the seam line, welding of two pipes is failed. The other is a gap size since a certain amount of gap is inevitable due to fabrication tolerance, or artificial allowances for smooth insertion of a pipe. However, it is required to restrict the gap allowance within 0.2mm to avoid undesirable undercut on a welding bead.

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열간 곡면성형된 Al5083 후판의 TIG 용접 시 루트갭 최소화를 위한 최적 블랭크 형상 결정 (Determination of Optimum Blank Shape to Minimize the Root Gap during TIG Welding in Hot Curvature Forming of Al5083 Thick Plate)

  • 이정민;고대훈;이경훈;이찬주;김병민
    • 한국정밀공학회지
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    • 제30권8호
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    • pp.815-823
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    • 2013
  • The hot curvature forming of large aluminum plates is a process used to produce spherical liquefied natural gas (LNG) tanks. In this study, we describe a method to determine the optimum shape of blanks to minimize the root gap in the forming process. The method proposed in this study was applied to a small-scale model for thick plates with a curvature of 1500 mm and thickness of 6 mm. First, the shape of the curved shells was determined as the target shape, and then a coordinate transform was used to determine the optimum blank shape, which was then iteratively modified using the results of finite element method (FEM) simulations, including heat transfer, until the shape error was minimized. Experiments in forming using Al5083 thick plate were carried out, showing that the method can determine the optimum blank shape within an allowable root gap of 0.1 mm.

Morphological and Biomechanical Study of the Pulley System of the Thumb

  • Kim, Ji-Won
    • 한국전문물리치료학회지
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    • 제12권4호
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    • pp.33-40
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    • 2005
  • The purpose of this study was to define more precisely the anatomy of the thumb flexor pulley system and to determine the relative contribution of each of the pulleys to the biomechanics of thumb motion at the metacarpophalangeal (MP) and interphalangeal (IP) joints. For this, 22 hands from 11 cadavers were used and randomly assigned to two groups. In the first group, the first annular (A1) pulley was cut first followed by the variable annular (Av) pulley and then the oblique pulley. In the second group, the oblique pulley was cut first followed by the, pulley and then the Av pulley. In 7 of 22 hands, it was a transverse structure parallel to the, pulley with a gap between the A1 and Av pulleys, referred to here as type I. In 9 hands, the A1 and Av pulleys were connected without any gap (type II). In 6 hands, the space between the A1 and Av pulleys were triangular in shape with fibers of the Av pulley converging toward the radial side (type III). In biomechanical study of both first and second experiments, there was no significant difference in MCP joint flexion between the all intact, A1 section, A1/Av section, A2 intact (A1/Av/oblique section), and no pulley configuration (p>.05). In occurring displacements less than 10 mm, there was no significant difference in IP joint flexion (p>.05). However, there was a significant decrease in IP joint flexion occurred in both 15 mm and 20 mm excursion (p<.05), when the oblique pulley was resected additionally after cutting the A1 and Av pulleys in first experiment, and when the A1 pulley was resected additionally after cutting the oblique pulley. According to the results, the injury of only the oblique pulley does not decrease thumb motion significantly. The oblique pulley injury with both the A1 and Av pulleys laceration decreased thumb motion significantly. The additional laceration of the A2 pulley does not decrease thumb motion.

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인공 슬관절의 응력 해석에 관한 연구 (Current Research on the Stress Analysis of Artificial Knee Joint)

  • 이재환
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2005년도 춘계 학술발표회 논문집
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    • pp.240-245
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    • 2005
  • 본 논문에서는 현재 진행 중인 인공 슬관절 연구에서 역학적 분석분야의 동향과 접촉 응력해석에 대하여 언급한다. 인공 관절 특히 슬관절은 인체에서 가장 크고 움직임이 복잡하여 인공 관절 설계가 어려우며 또한 이에 대한 생체역학적 실험이 쉽지 않다. 무엇보다도 외국에서 연구가 활발하고 제품 생산도 선진국에서 주도하고 있으며 그 기술 격차는 매우 큰 현실이다. 최근까지 발표된 논문과 특히 실험과 수치해석이 병행되어 우수한 결과가 발표된 논문 내용을 중심으로 역학 분야를 소개하고자 한다. 접촉 유한요소해석이 수행된 내용도 일부도 포함된다.

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3차원 영상기법을 이용한 천장골염의 조기 진단 (The Application of 3-dimensional Surface Imaging to the Early Detection of Sacroiliitis)

  • 전재한;김선일;이두수
    • 대한의용생체공학회:의공학회지
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    • 제14권3호
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    • pp.235-242
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    • 1993
  • In the early stage of sacroilitis, it is'difficult to detect sacroiliac(Sl) abnormalities by conventional plain X-ray even though there are characteristic symptoms of ankylosing spondylitis. 3 dimensional volume rendering from the CT image was performed to make an early de tection of the structural changes of Sl joint. 2 cases who had clinical impression of ankylosing spondylitis without sacroilitis in plane X-ray and 1 case of typical ankylosing spondylitis as well as 1 case of normal control were studied. The Sl Joints were separated and each joint surface of sacrum and ilium was independently reconstructed by a special 3D manipulation program. All 2 patiant who complained of inflammatory lower back pain with no abnormal findings in the plain X-ray showed structural changes in 3 dimensionally reconstructed surface Image of the Sl joint compared to the normal control. Authors tried several parameters, such as fourler analysis of each surface and the mean and variance of Sl joint gap. We couldn't tell the statistical significance because of the limited number of cases. However, the parameters showed difference according to the progression of disease.

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한국 사과 주산지의 지역농협 연합판매사업의 전개 - 전라북도 무주군을 사례로 - (Development of Joint Sales Business by Regional Agricultural Cooperatives in a Major Apple Production Region of Korea - Focused on the Case of Muju County, North Jeolla Province -)

  • 황성일
    • 한국유기농업학회지
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    • 제30권3호
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    • pp.313-333
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    • 2022
  • In Muju County, one of Korea's major apple producers, the regional agricultural cooperatives united together and invested to establish a cooperative joint business corporation in charge of the sales business. The corporation carried out the sales business transferred from the participating regional agricultural cooperatives. While the two participating cooperatives showed a marked difference in the degree of participation at the beginning of the business, the introduction of the agricultural product processing centers (APCs) and the participation of co-selection and shipment organizations and general farms helped settle this gap. In addition, commercialization through the APCs enhanced the market competitiveness of apples, which led to the stable securing of sales outlets. The corporation integrated the sales business in the county and this resulted in increased sales volume and sales revenue. Playing a leading role in introducing and cultivating new crops on a trial basis, the corporation demonstrated its potential as the main body of the joint sales business.

Effect of flexion degrees in elbow joint on muscle activation of the extensor carpi radialis and biceps brachii muscles in healthy young adults

  • Kim, Gap-Cheol;Hwang, Sujin
    • Physical Therapy Rehabilitation Science
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    • 제5권3호
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    • pp.120-124
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    • 2016
  • Objective: Chronic lateral epicondylitis is a condition which becomes sore and tender on the lateral side of the elbow joint damaged from overuse and repetitive use of the extensor muscles of the forearm. The purpose of this study was to investigate the effects of flexion degrees in the elbow joint on extensor carpi radialis longus and brevis and biceps brachii muscles in individuals with healthy young adults. The main purpose of this study was to suggest the feasibility of optimal elbow angle during therapeutic eccentric exercise with resistance for strengthening of wrist extensors. Design: Cross-sectional study. Methods: Thirty health young adults (male 15, female 15) participated in this study. This study measured muscle activation in four different conditions of elbow flexion, $0^{\circ}$, $30^{\circ}$, $60^{\circ}$, and $90^{\circ}$ during eccentric exercise with weight loading in wrist extensors, extensor carpi radialis longus and brevis and biceps brachii muscles using surface electromyography. Results: The muscle activation of extensor carpi radialis showed a negative relationship with the degrees of elbow joint flexion. With increasing elbow flexion angles, the ECRL muscle activation amount was significantly lower (p<0.05). In contrast, the muscle activation of the ECRB muscle activation amount was significanlty higher (p<0.05). Conclusions: This study suggests that the eccentric exercise of wrist extension with selected activation of wrist extensor muscles according to elbow flexion positions, and suggests that the extensor carpi radialis longus and brevis will need to be strengthened for preventing and treating chronic lateral epicondylitis regardless of degrees of elbow joint flexion.

궤도가속실험을 통한 포장궤도 토공구간 시공이음매부의 변형특성 연구 (Deformation Characteristics of Construction Joint of Paved Track on Earthwork Section using the Accelerated Track Test)

  • 이일화;장승엽;강윤석;엄주환;김은
    • 한국철도학회논문집
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    • 제13권5호
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    • pp.521-527
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    • 2010
  • 포장궤도는 토공구간, 교량구간, 터널구간, 분기기구간 등 모든 구간에서 유지보수를 절감할 목적으로 적용한다. 토공구간에 포장궤도를 적용할 경우, 내구성에 가장 큰 영향을 미치는 것은 시공이음매부로서 구조적인 문제는 없으나 슬래브의 불연속으로 인한 단차가 발생하여 장기적인 사용성에 영향을 미칠 가능성이 있다. 따라서 이에 대한 검토를 위하여 실물의 포장궤도를 제작하여 시공이음매부와 연속부에서 가속실험을 실시하였다. 가속실험에서는 각 재하하중별 변위와 토압에 대한 경향을 비교함으로써 시공이음매부에서의 취약도를 평가하고자 하였다.

Optional Tariffs for Channel Coordination

  • Song, Jae-Do
    • Asia Marketing Journal
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    • 제14권3호
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    • pp.49-68
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    • 2012
  • When a channel is vertically separated, there can be inefficiencies, double marginalization. Channel coordination to amend this inefficiency has been an important issue in marketing and economics. Channel coordination deals with maximization of joint profit and achieving proper profit sharing among participants. In this paper, a manufacturer and heterogeneous multiple retailers with exclusive territory are assumed, and channel coordination with two-part tariff is considered. When multiple heterogeneous retailers are assumed, profit sharing can be an issue even though the tariffs based on marginal cost can maximize joint profit. In case of multiple heterogeneous retailers, the manufacturer earns the same profit (fixed fee) from each retailer. This means that a large retailer occupies all the gaps of channel profit between small and large markets. Then, the manufacturer, which generally plays the role of Stackelberg leader, will consider increasing fixed price or marginal price to earn more profit from large retailer. Those reactions can sacrifice maximization of joint profit by making small retailer withdraw or by changing the sales quantities. In this paper, to maximize joint profit and achieve proper profit sharing, two kinds of optional tariffs are considered. The first is an optional two-part tariff based on marginal cost and the second is an optional modified two-part tariff in which marginal prices are higher than the manufacturer's marginal cost. In both types of optional tariffs, maximization of joint profit in each market can be achieved. Moreover, optional tariffs alleviate the problem of profit sharing. Optional tariffs can provide a manufacturer more profit from a large retailer when profit from a small retailer is given. However, the analysis shows that the maximum share of manufacturer from a large retailer is restricted by the condition for self-selection. In case of optional two-part tariffs based on marginal cost, if the gap between demands is large, the maximum share of the manufacturer is sufficient to achieve proper profit sharing. If the gap between demands is not sufficiently large, the manufacturer cannot earn sufficient share from increased profit. An optional modified two-part tariff where marginal price is more than marginal cost of manufacturer is considered because of this scenario. The marginal price above the marginal cost may additionally control the distribution of the increased profit. However, the analysis shows that a manufacturer's maximum profit from a large retailer with given profit from a small retailer is the same as or lower than the maximum profit when optional two-part tariffs based on marginal cost are applied. Therefore, it can be concluded that the optional modified tariffs do not have additional contribution to profit sharing relative to the tariffs based on marginal cost. Although this paper does not cover all kinds of optional tariffs that are different from tariffs based on marginal cost, it shows the advantage of optional tariffs based on marginal cost and has important theoretical implications. The result of this paper also gives guide for channel coordination. Optional two-part tariff based on marginal cost can increase efficiency in channel coordination.

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