• International Journal of Reliability and Applications
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• v.10 no.2
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• pp.63-79
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• 2009

A new bivariate linear failure rate distribution is introduced through a shock model. It is proved that the marginal distributions of this new bivariate distribution are linear failure rate distributions. The joint moment generating function of the bivariate distribution is derived. Mixtures of bivariate linear failure rate distributions are also discussed. Application to a real data is given.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.239-244
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• 2002

The reinforcing bar computation have to be reflected stress distribution and geometrical condition of a comer joint when the closing moment acted at comer joint. This study analyzes stress distribution of a corner joint with statically determinate truss model. Compared with FEM analysis and result of truss model suggested design method consider strengthening efficiency of main reinforcement.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.10
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• pp.1082-1090
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• 2008

In this paper, a general solution for the vibrational energy and intensity distribution through a compliant and dissipative joint between plate structures is derived on the basis of energy flow analysis (EFA). The joints are modeled by four sets of springs and dashpots to show their compliancy and dissipation in all four degrees of freedom. First, for the EFA, the power transmission and reflection coefficients for the joint on coupled plate structures connected at arbitrary angles were derived by the wave transmission approach. In numerical applications, EFA is performed using the derived coefficients for coupled plate structures under various joint properties, excitation frequencies, coupling angles, and internal loss factors. Numerical results of the vibrational energy distribution showed that the developed compliant and dissipative joint model successfully predicted the joint characteristics of practical structures vibrating in the medium-to-high frequency ranges. Moreover, the intensity distribution of a compliant and dissipative joint is described.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.3
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• pp.279-284
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• 2014

PURPOSE: This study intended to verify whether there was actual correlation between weight-bearing asymmetry and a limitation in hip joint rotation range in patients with low back pain. METHODS: Thirty five low back pain patients voluntarily participated this study. For each participant, hip joint medial rotation symmetry rate and the weight-bearing symmetry rate were calculated. The correlation between the two variables was investigated. RESULTS: A decrease in the left hip joint medial rotation range of motion (ROM) was observed more often than a reduction in the right hip joint medial rotation ROM. However, similar number between right and left side was observed in ground reaction force more weighted. The coefficient between the passive hip joint medial rotation symmetry rate and the weight loading symmetry ratio was -0.19 (p < 0.05). CONCLUSION: The present study demonstrated a weak correlation between the hip joint medial rotation ROM and the weight distribution of both feet. Such result suggests that careful evaluation by separating each element is needed in treating patients with low back pain. Future research should take into account asymmetric alignment and abnormal movement in different joints of the body as well as asymmetry in the bilateral hip joint rotation and the unilateral weight supporting posture.

• Journal of Ocean Engineering and Technology
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• v.10 no.2
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• pp.106-119
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• 1996

The ceramic has various high mechanical properties such as heat, abrasion, corrosion resistance and high temperature strength compared with metal. It also has low speciffic weight, low thermal expansibillity, low thermal conductivity. However, it could not be used as structural material since it is brittle and difficult for the machining. Therefore, there have been many researches to attempt to join ceramic with metal which is full of ductillity in order to compensate the weakness of ceramic.The problem is that residual stress develops around the joint area while the ceramic/metal joint material is cooled from high joining temperature to room temperature due to remarkable difference of thermal expansion coefficients between ceramic and metal. Especially, the residual stress at both edges of the specimen reduces the strngth of joint to a large amount by forming a singular stress field. In this study, two dimensional finite element method is attempted for the thermal elastic analysis. The joint residual stress of ceramic/metal developed in the cooling process is investigated and the change of joint residual stress resulted from the repetitive heat cycle is also examined. In addition, it is attempted to clarify the joint stress distribution of the case of tensile load and of the case of superposition of residual stress and actual loading stress.

• Journal of Acupuncture Research
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• v.18 no.5
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• pp.33-42
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• 2001

Objective : To evaluate the effect of treatment for Rheumatoid arthritis by using Bee-venom Acupuncture that is well known for anti-inflammatory effect and function of activating immune system. Methods : Evaluated the result of Bee-venom Acupuncture treatment twice in a week for patients who diagnosised as rheumatoid arthritis by 7 criteria of US Rheumatism Academy. Results : 1. If you see the distribution chart, sexual rate of male and female was 1:2.75 and age distribution shows as age ascend it shows high. 2. If you see the duration distribution, it shows chronic tendency in order of more than 6 months (59.5%), 2 to 5 months, and 1 month. 3. If you see the invaded region distribution, it shows chronic tendency in order of finger(17 cases), wrist joint(16 cases), knee joint(16 cases), ankle joint(10 cases), elbow joint(8 cases), shoulder joint(7 cases), feet(7 cases), hip joint(5 cases), low back(3 cases) and neck(2 cases). 4. If you see the result of duration distribution treatment, the improvement index is rising in order of within a month, 2 to 5 months, and over 6 months. So it shows that it has good result of treatment within a month. 5. If you see the invaded region, it shows high improvement index in order of low back, hop joint, shoulder joint, wrist joint, feet, knee joint, finger, elbow joint, ankle joint and neck. 6. If you see the result of morning stiffness time before treatment, it shows good effect of treatment in order of 2-3hrs, 30min.-an hr, an hr to 2hrs, and 0-30min. 7. If you see the patients satisfaction after Bee-venom Acupuncture treatment, Excellent is 6 cases, Good is 7 cases, and Moderate 2 cases. Conclusions : It will have greater treatment effect if herbal medicine, moxibustion, and acupuncture are used together as patients whole body condition and symptoms with Bee-venom Acupuncture for rheumatoid arthritis that is chronic inflammatory disease.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.535-536
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• 2011

This paper studies the validity about a joint operation of neutral wire and overhead grounding wire in combined distribution systems. The overhead grounding wire and neutral wire are currently installed separately and grounded by common. However there is no any ineffectiveness or electrical problem in case of the proposed system, such system can be operated at real distribution system. Therefore this paper describes the suitability of a joint operation through lightning surge analysis on combined distribution systems and analyzes the optimal position of lightning arrester on joint operation of neutral wire and overhead grounding wire. Lightning surge analysis is carried out by EMTP/ATPDraw to obtain the overvoltage of overhead line and underground cable in various conditions such as location and current types of lightning stroke. Over voltage gained by the analysis show that the insulation strength of the joint operation case is not stable compare with the current operation case.

• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.13-17
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• 2006

The elasto-plastic finite element method (FEM) was used to investigate the effect of off-center recessing location (8 mm length) on the stress distribution in the lap zone of adhesively bonded aluminium double lap joint. The results from simulation showed that the effect of off-cent recessing in bondline of double lap joint in the mid-bondline is not evidently to stress distribution in mid-bondline but the peak stresses both in mid-bondline and in the interface near the adherend side of the joint may increase markedly when an 8 mm length recessing was arranged symmetrical to the point of x =18 mm. When shifting an 8 mm length recess from near left end to the right end of the lap zone, all the highest peak stresses in the mid-bondline occurred under the condition of recess arranged symmetrical to the point of x = 6 mm.

• Journal of the Korean GEO-environmental Society
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• v.17 no.1
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• pp.29-37
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• 2016

This study examined the magnitude and distribution of earth pressure on the support system in a jointed rock mass due to the different joint spacing as well as varying the rock type and joint condition (joint shear strength and joint inclination angle). Based on a physical model test and its numerical simulation, a series of numerical parametric analyses were conducted using a discrete element method. The results showed that the magnitude and distribution of earth pressure were strongly affected by the different joint spacing as well as the rock type and joint condition. In addition, the study results were compared with Peck's earth pressure for soil ground, which indicated that the earth pressure in a jointed rock mass could be considerably different from that in soil ground. The study suggests that the joint spacing as well as the rock type and joint condition are important factors affecting the earth pressure in a jointed rock mass and they should be considered when designing a support system in a jointed rock mass.

• Tunnel and Underground Space
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• v.26 no.3
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• pp.201-211
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• 2016

A method for estimating rock joint size distribution using contained traces length distribution from 3D cylindrical window survey was suggested. To reduce the numerical error, an improved technique was applied. The accuracy was verified by referring to Monte-Carlo simulation and it was found that the error can be decreased with suitable gamma values.