• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.65-68
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• 2004

In the seismical capacity evaluation for RC structure wall-slab joint is very important factor. Because lateral load is resistance element and gravity load resistance element are acted mutually in the wall-slab joint. In this paper, to improve the seismic capacity of the wall-slab joint in the existing wall type apartments experiment which improve and retrofit a seismic capacity by unequal angle bracing and carbon sheet attachment are carried out. These methods are also economic and simple in mitigating seismic hazard, improve earthquake-resistance performance, and reduce risk level of building occupants. From the experimental results, the change of strength, degration of stiffness, and energy dissipation are evaluated. It can be concluded that these methods are effective in improving the seismic performance.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.749-758
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• 2007

Learning has become an important aspect for any organization to stay relevant and competitive in the corporate world of survival. In construction industry, the international construction joint ventures (ICJVs) provide an excellent platform with opportunity of learning among partners seeking to develop new area of competency and improve their overall competitiveness for their next project endeavor. This paper discusses the development of a conceptual model of effective learning in ICJVs using four major stages of development in a typical joint venture (JV) 's process. The study identified that there are three key constructs that contribute to effective learning comprising learning conditions in the JV's pre-inception stage, success factors of JV for learning in the forming & organizing stage, and learning actions in the implementation & adjustment stage. The effective learning outcomes are measured by the characteristics of learning organization during the JV's completion & evaluation stage. Details and issues of each stage and the methodology of research will be presented and discussed.

• Advances in Computational Design
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• v.1 no.1
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• pp.61-77
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• 2016

Seismic performance of structures depends on the force flow mechanism inside the structure. Discontinuity regions, like beam-column joints, are often affected during earthquake event due to the complex and discontinuous load paths. The evaluation of shear strength and identification of failure mode of the joint region are helpful to (i) define the strength hierarchy of the beam-column sub-assemblage, (ii) quantify the influence of different parameters on the behaviour of beam-column joint and, (iii) develop suitable and adequate strengthening scheme for the joints, if required, to obtain the desired strength hierarchy. In view of this, it is very important to estimate the joint shear strength and identify the failure modes of the joint region as it is the most critical part in any beam-column sub-assemblage. One of the most effective models is softened strut and tie model which was developed by incorporating force equilibrium, strain compatibility and constitutive laws of cracked reinforced concrete. In this study, softened strut and tie model, which incorporates force equilibrium equations, compatibility conditions and material constitutive relation of the cracked concrete, are used to simulate the shear strength behaviour and to identify failure mechanisms of the beam-column joints. The observations of the present study will be helpful to arrive at the design strategy of the joints to ensure the desired failure mechanism and strength hierarchy to achieve sustainability of structural systems under seismic loading.

• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.1
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• pp.213-221
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• 2002

This paper presents the experimental result of Reinforced Concrete column-steel beam joint connected by Band Plates(BP). Main parameters in the test are the shape of BP and thickness of plate. Ten interior and exterior RC column-steel beam joint specimens are designed. Cyclic loads are applied to the beam end of eight specimens (four interior specimens and four exterior specimens). To evaluate the cyclic effect, monotonic loads are acted for two specimens. All specimen showed similar failure pattern such as the plate of BP get torn after the large deformation. Even though the specimen with double cross type BP has lower strength than the specimen with single cross type BP, the energy dissipation capacity of the specimen turned out high. Thus, provided the strength of joint with double cross type to be designed to have suitable strength by increasing the thickness of plate, the joint system may show higher seismic capacity.

• The Journal of Korean Physical Therapy
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• v.34 no.5
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• pp.242-247
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• 2022

Purpose: This study investigates the effect of 60° semi-squat exercises according to three different types of support surfaces. The effects were examined on joint position sense and balancing ability using stable and unstable surfaces in patients afflicted with post-stroke hemiplegia. Methods: Subjects were instructed to perform three sets of 60° semi-squat exercises according to the characteristics of the support surface conditions. The three ground states were bilateral stable surface (BSS), nonaffected side unstable surface (NUS), and bilateral unstable surface (BUS). The joint position sense, characteristics of body sway, and dynamic balance were analyzed according to floor conditions before and after the experiment. A balance-pad (50 cm W×41 cm L×6 cm H; Alcan Airex AG, Sins, Switzerland) was used for the unstable floor. Results: The 60° semi-squat exercises applied to hemiplegic patients showed the highest statistical significance in joint position sense in the NUS group, and Timed Up and Go test (TUG) in the BUS group (p<0.05). Conclusion: Functional training using an unstable surface can be applied as a meaningful intervention method for improving the balance and joint position sense of stroke patients.

• Korean Journal of Veterinary Research
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• v.33 no.1
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• pp.7-21
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• 1993

The morphogenesis of the stifle joint in Korean cattle embryos and fetuses was observed by radiography, alizarin red S stain and light microscopy. Fourty-eight(48) embryos and fetuses, ranging from 11mm to 160mm in crown-rump length (C-R L), were used for this study. The experimental samples were divided into twelve separate groups according to their C-R L. The first to the nineth group ranged from 11-100mm in C-R L, spaced at 10mm intervals. The tenth to the twelfth group ranged in C-R L from 101mm to 160mm, and were spaced at 20mm intervals. The results were as follows; 1. The first appearance of the interzone between the femur and tibia was formed in the second experimental group. The patellar ligament and cruciate ligament appeared in the third group and the patella, menisci and synovial cavity appeared in the fourth group. 2. The lateral and medial menisci were first obseved in the fourth group, and these structures showed crescent shape in the fifth group of the fetuses. 3. The first appearance of the femoro-tibial joint cavity was in the third group. The fifth group contained the first appearance of the patello-femoral cavity. Also, the femoro-tibial cavity was divided into two cavities by the anterior and posterior cruciate ligament.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.450-453
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• 2002

In this paper a Phase-based virtual image encryption and decryption techniques based on a joint transform correlator (JTC) are proposed. In this method, an encrypted image is obtained by multiplying a phase-encoded virtual image that contains no information from the decrypted image with a random phase. Even if this encryption process converts a virtual image into a white-noise-like image, the unauthorized users can permit a counterfeiting of the encrypted image by analyzing the random phase mask using some phase-contrast technique. However, they cannot reconstruct the required image because the virtual image protects the original image from counterfeiting and unauthorized access. The proposed encryption technique does not suffer from strong auto-correlation terms appearing in the output plane. In addition, the reconstructed data can be directly transmitted to a digital system for real-time processing. Based on computer simulations, the proposed encryption technique and decoding system were demonstrated as adequate for optical security applications.

• The Journal of Korean Physical Therapy
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• v.19 no.1
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• pp.23-31
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• 2007

Purpose: As a preliminary study, the purpose of this study was to examine the indirect estimation of the lumbar intervertebral disc size by two anthropometric methods, in order to compare these indirect methods with the direct analysis by radiological imaging. Methods: The wrist, elbow, knee, and ankle joint (both right and left) diameters were measured in 52 volunteers, and then intervertebral disc size was calculated using two anthropometric methods (Colombini and modified Colombini). The data were analysed with independent t-test to assess clinical usefulness. Results: When using right and left joint diameter, there was no significant difference in the estimation value of the L4-5 and L5-S1 intervetebral disc sizes. However, the study has shown that male subjects have significantly larger L4-5 and L5-S1 intervertebral disc sizes, compared with those of female subjects. In addition, disc sizes calculated by Colombini's formula were significantly larger than modified Colombini's formula. Conclusion: The indirect estimation of the intervertebral disc size by anthropometric method can be considered as a clinically useful method. However, further study should be conducted to compare anthropometric values with other radiological imaging.

• Journal of the Korean Society of Physical Medicine
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• v.14 no.2
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• pp.21-28
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• 2019

PURPOSE: This study was conducted to compare different standing postures with the use of standing aids for lumbar spine posture and muscle activity, and to identify the most desirable standing posture. METHODS: The lumbopelvic angle was assessed based on static radiographic measurement on the sagittal plane. Lumbar lordosis, lumbosacral lordosis, and the intervertebral joint angle at L1/L5 and L5/S1 were measured using radiography in three standing postures (standing on level ground, standing with one foot on a platform, and standing on a sloped surface). In addition, muscle activity was measured using surface electromyography to examine the co-contraction of the lumbar and hip muscles. RESULTS: Lumbar lordosis, lumbosacral lordosis, and L5/S1 intervertebral joint flexion occurred with one foot on the platform. No significant differences were found between standing on a sloped surface and standing on level ground. However, muscle co-contraction was reduced with the use of standing aids. CONCLUSION: This study demonstrated that standing with a foot on a platform induced lumbar lordosis, but that there was no significant difference between standing on a sloped surface and standing on level ground. However, muscle co-contraction was reduced with the use of standing aids. Based on the motor control pattern as a predictor of LBP, the use of standing aids would help workers during prolonged standing.

• Structural Engineering and Mechanics
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• v.70 no.4
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• pp.467-477
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• 2019

The objective of this work is to analyze by traction tests, the mechanical behavior of an assembly of type metal / metal by various assembly processes; bonding, riveting and hybrid, on the one hand to show the advantage of a hybrid assembly with respect to the other processes, and on the other hand, to analyze by the finite element method the distribution of the stresses in the various components of the structure and to demonstrate the effectiveness of the use of a hybrid assembly with respect to other processes. The number of rivets has been considered. The results show clearly that the value of the different stresses is reduced in the case of a hybrid junction and that the number of rivets in an assembly can be reduced by using a hybrid joint.