• Earthquakes and Structures
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• 제20권1호
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• pp.29-38
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• 2021

According to ACI 224.3R-95 (ACI, 2013), construction joints (cold joint) in the column are to be provided at the top of floor slab for column continuing to the next floor and underside of floor slab and beam. A recent study reveals that providing cold joint of the mentioned location significantly reduced the seismic performance of the frame structures. Since, the construction joints in multi-story frame structures normally provided at the top of the floor slabs and at soffit of the beam in the column. This study investigated the effect of construction joint at various location in the column of beam-column joint such as at the top of floor slab, soffit level of the beam, half the depth of beam below the soffit of the beam and at a full depth of the beam below the soffit of the beam. The study revealed that there is an improvement in seismic capacity of the specimens as the location of cold joint is placed away from the soffit of the beam for lower story column.

• Journal of the Korean Wood Science and Technology
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• 제41권4호
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• pp.318-326
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• 2013

소나무와 스프루스재를 사용하여 핑거공차를 0.15 mm로 고정하고 핑거피치 4.4 mm (Type S)와 6.8 mm(Type L)의 2종류 및 레조시놀 페놀 수지 접착제 및 수용성 비닐 우레탄 수지접착제로 2종류의 사용하여 종접합시키고 또한 2본의 종접합재를 이용하여 횡방향으로 핑거접합부를 양쪽으로 이동시키면서 접착하여 핑거접합부위의 배치거리를 접합재의 두께를 기준으로 하중점 중앙으로부터 양쪽 핑거접합부까지의 거리를 접합재 두께의 비율($R_t$) 0, 1.5, 2, 2.5, 3배의 5조건으로 제조하여 3점 중앙집중식 휨강도성능시험을 한 결과는 다음과 같다. 1) 휨탄성계수는 핑거접합부의 위치 이동과 관계없이 접착제의 종류, 핑거의 형상에 따른 영향은 나타나지 않았다. 2) 휨강도는 접착제의 종류, 핑거의 형상에 관계없이 하중점 중앙에서부터 멀어질수록 거의 직선적으로 증가하였으며 핑거접합부가 소재두께 비율의 3배에서는 소재와 같은 값을 나타내었다. 3) 시험편의 파괴는 하중점 중앙에서부터의 핑거접합부까지의 거리가 두께의 비율이 0, 1.5배에서 모두 핑거접합부에서 파괴되었으며 거리가 멀어질수록 접합부에서의 파괴가 적게 일어나다가 두께비율의 3배에서는 전혀 나타나지 않았다.

• 대한산업공학회지
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• 제26권1호
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• pp.73-80
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• 2000

To determine the exact direction and location of the human joint in motion is crucial in developing a more accurate human model and producing a more fitting artificial joint. There have been several reports on the biomechanical analysis of the joint to determine the anatomy and movement of joints. However, all the previous researches were made in vitro study, that is, they investigated the passive movement of the joint from cadavers and the suggested location of the joint axis was difficult to make practical applications due to the lack of the direction of joint axis. Also, in many biomechanical models, each joint axis is assumed to lie horizontally or vertically to the adjacent links. Such an assumption causes inherent inaccuracy. In this study, the direction and location of the transverse elbow axis was obtained with respect to the global coordinate system whose origin is on the lateral epicondyle of the humerus. The suggested result based on the global coordinate system lying on the external landmark will be helpful to understand the information of the axis and to make an application. From the experiments conducted for five subjects, the direction and location of the elbow transverse joint was determined for each subject by the helical axis method. A statistical validation was also performed to confirm the result. Finally, the result was applied to develop a simple elbow model which is a part of the kinematic arm model. The simple elbow movement model was developed to validate the significance of the result and the kinematic arm model was able to describe the geometry of any complex linkage system. As a result, the errors incurred from the proposed model were significantly reduced when compared to the ones from the previous approach.

• 터널과지하공간
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• 제23권5호
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• pp.392-400
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• 2013

채굴적에 의한 지표에서의 지반침하발생 위치를 추정함에 있어, 절리군은 필수적으로 고려되어야하는 요소 중의 하나인 바, 각 절리군의 역학적 특성과 이들이 채굴적 상부 암반에 분포하는 양상은 지반침하발생을 가속시킬 수 있다. 따라서 본 연구에서는 침하발생 범위의 추정에 관한 선행연구의 근거자료로 이용된 자료 중 절리군의 방향성에 대한 조사정보의 신뢰성이 비교적 양호한 자료들을 선별하여 절리군의 방향성을 중심으로 지반침하 발생위치와의 상관관계를 재검토하였으며, 추정각과 침하 지역에 분포하는 주절리군 $J_1$의 경사각을 비교하여 주절리군 $J_1$이 침하에 미치는 영향을 분석하였다.

• Korean Journal of Acupuncture
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• 제27권3호
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• pp.97-108
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• 2010

Background : The location of acupoints on rat, which may differ from that of human body due to anatomical structure, is defined variously among researchers, which may cause the problem of low repeatability and objectivity. Design : The measurement of hind limb consist of measuring the distance between knee joint and tibia tubercle in order to set the knee joint as common criteria. Based on it, the three mostly referred location of ST36 were represented with the knee joint as a datum point and compared. The electroacupuncture stimulation was administrated after the abdominal pain was induced by acetic acid. And the analgesic activity of each ST36 acupoint was evaluated by measuring the number of writhing reflex, in order to observe the differences of treatment effect in accordance with the location of ST36 acupoints. Results : The result of measurement confirmed the differences in the acupoint location of ST36 among researchers. The writhing reflex test using the acetic acid-induced abdominal pain stimulated with electroacupuncture of 100Hz showed that there were statistically significant differences in the analgesic effect between control group and three ST36 groups (P<0.05). However there were no differences observed among three mostly referred location of ST36 acupoints (P>0.05). Conclusions : We recommend "the point located 6.5 mm below the knee joint at the anterior tibial muscle" as a standard ST36 acupoint location qualified by the WHO Standard Acupuncture Point Locations in 2008.

• Journal of Advanced Marine Engineering and Technology
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• 제31권4호
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• pp.350-355
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• 2007

Pad-eye is connected to crane with sling. When block is lift, pad-eye have a various applied force. Applied force on pad-eye is related to sling angle. Sling angle is decided by various parameters, including pad-eye location, sling length and crane location. Welded joint on pad-eye requires strength design because sling angle changes force on pad-eye. Strength design for welded joint of pad-eye will calculate with general mechanical design and FE analysis. FE analysis would become a useful tool in the analysis of welded joint. A commercial software(ANSYS 10.0) was used in the structural strength analysis for welded joint of pad-eye.

• Parasites, Hosts and Diseases
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• 제55권4호
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• pp.429-431
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• 2017

Hydatid cyst is usually located in the liver and lungs, rare cases showing localization in other organs or tissues. In the unusual location, echinococcosis is an excluding diagnosis that is established only after microscopic evaluation. Our first case occurred in a 67-year-old female previously diagnosed with pulmonary tuberculosis and hospitalized with persistent pain in the hip joint. The clinical diagnosis was tuberculosis of the joint, but the presence of the specific acellular membrane indicated a hydatid cyst of the synovial membrane, without bone involvement. Fewer than 25 cases of joint hydatidosis have been reported in literature to date. In the second case, the intramural hydatid cyst was incidentally discovered at autopsy, in the left heart ventricle of a 52-year-old male hospitalized for a fatal brain hemorrhage, as a result of rupture of an anterior communicating artery aneurysm. The conclusion of our paper is that echinococcosis should be taken into account for the differential diagnosis of cystic lesions, independently from their location.

• 대한산업공학회지
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• 제25권1호
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• pp.56-66
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• 1999

Shoulder joint is the most movable joint in human body with, at least, three degrees of freedom, since there are at least three bones and five joints involved in shoulder movement. Due to the complexity of the shoulder joint and the lack of appropriate anatomical data, modeling of the shoulder joint has been known to be extremely difficult. In many biomechanical models being used, shoulder joint is considered as a fixed point and it is also assumed that the shoulder joint does not noticeably move during the shoulder movement. However, such an assumption is not valid in real applications and causes inaccuracy, especially, in the area of workspace evaluation. The reachable area generated by a human becomes somewhat different from that of current models for those models fail to appropriately reflect the movement of shoulder joint's center of rotation. In this study, the location of the shoulder joint's center of rotation was obtained in relation to the location of humerus, on which a new model for reach envelope generation was developed for workspace evaluation. From the experiments conducted for three subjects, the initial location of the center of rotation was determined for each subject and subsequent changes in the instantaneous center of rotation were drawn as a function of flexion and abduction of the shoulder. Based on the regression analysis, the study suggested a new method for the generation of reach envelope. Comparisons were also made among real reach envelopes obtained from the experiment, the ones from the model, and the ones from the new method suggested in the study. As a result, the prediction errors incurred from the new method were significantly reduced when compared to the ones from the current approach.

• Structural Engineering and Mechanics
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• 제74권6호
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• pp.723-735
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• 2020

This study is reported the adhesion failure in adhesive bonded composite and specifically for the T-joint structure. Three-dimensional finite element analysis has been performed using a commercial tool and the necessary outcomes are obtained via an eight noded solid element (Solid 185-element) from the library of ANSYS. The structural analysis input has been incurred through ANSYS parametric design language (APDL) code. The normal and shear stress distributions along different layers of the joint structure have been evaluated as the final outcomes. Based on the stress distributions, failure location in the composite joint structure has been identified by using the Tsai-Wu stress failure criterion. It has been found that the failure index is maximum at the interface between flange and web part of the joint (top layer) which indicates the probable location of failure initiation. This kind of failures are considered as adhesion failure and the failure propagation is governed by strain energy release rate (SERR) of fracture mechanics. The different adhesion failure lengths are also considered at the failure location to calculate the SERR values i.e. mode I fracture (opening), mode II fracture (sliding) and mode III fracture (tearing) along the failure front. Also, virtual crack closure technique (VCCT) principle of fracture mechanics steps is used to calculate the above said SERRs. It is found that the mode I SERR is more dominating compared to other two modes of failure for the joint considered. Finally, the influences of various parametric (geometrical and material) effect on SERR of the joint structure are evaluated and discussed in details.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.328-335
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• 2022

With the advance of robot capabilities and functionalities, construction robots assisting construction workers have been increasingly deployed on construction sites to improve safety, efficiency and productivity. For close-proximity human-robot collaboration in construction sites, robots need to be aware of the context, especially construction worker's behavior, in real-time to avoid collision with workers. To recognize human behavior, most previous studies obtained 3D human poses using a single camera or an RGB-depth (RGB-D) camera. However, single-camera detection has limitations such as occlusions, detection failure, and sensor malfunction, and an RGB-D camera may suffer from interference from lighting conditions and surface material. To address these issues, this study proposes a novel method of 3D human pose estimation by extracting 2D location of each joint from multiple images captured at the same time from different viewpoints, fusing each joint's 2D locations, and estimating the 3D joint location. For higher accuracy, the probabilistic representation is used to extract the 2D location of the joints, considering each joint location extracted from images as a noisy partial observation. Then, this study estimates the 3D human pose by fusing the probabilistic 2D joint locations to maximize the likelihood. The proposed method was evaluated in both simulation and laboratory settings, and the results demonstrated the accuracy of estimation and the feasibility in practice. This study contributes to ensuring human safety in close-proximity human-robot collaboration by providing a novel method of 3D human pose estimation.