• Journal of muscle and joint health
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• v.16 no.1
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• pp.5-12
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• 2009

Purpose: The purpose of this study was to investigate bone mineral density(BMD) and fear of falling and falls efficacy in the middle and old aged women over 50 years. Methods: The subjects consisted of 409 women. One-way ANOVA, Pearson's correlations and multiple regression were used to test the BMD, fear of falling and falls efficacy scale by using SPSSWIN 12.0. The BMD of the calcaneus were measured with peripheral dual energy x-ray absorptiometry(DEXA). Results: The average age was 63 years old and the average T-score was -3.21 in patient with osteoporosis, -1.72 with osteopenia, and .13 with normal. There were significant differences in the status of the BMD according to age(p=.000), height(p=.000), weight(p=.000), married status(p=.000), age of menarche(p=.002), and menopause(p=.002). The fear of falling was related with falls efficacy(r=-.247, p=.01), BMD(r=-.337, p=.01). Falls efficacy($\beta$=-.21, p=.000)and BMD($\beta$=-.26, p=.000) were predicting variables of fear of falling. The model explained 13% of the variance in fear of falling(F=27.38, p=.000). Conclusion: Fear of falling and falls efficacy were related with the bone mineral density. Falls efficacy and BMD may be useful for the predicting fear of falling for women in middle and old age. Further studies with assessment of fall-related risk-factors and a longitudinal study are necessary to assess with falls efficacy, and BMD with age.

• Magazine of the Korea Concrete Institute
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• v.6 no.1
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• pp.120-130
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• 1994

The purpose of this study is to propose the analytical model for the hysteretic behavior of Reinforced Concrete bearn-column joints under various loading history. Discrete line elernents , YVith inelastic rotational spring was adopted to consider the movement of plastic hinging zone influenced by the details of longitudinal reinforcements. Also hysteretic model was constructed by excluding such variables which can not be utilized in dynamic analysis of Reinforced Concrete. structure that it will be adoptable in two-dimensional inelastic frame ardysis with 6-DOF. From the analysis of previous test results, it was found that stiffness deterioration caused by inelastic hysteretic loadings can be predicted by the functron of basic pinching coefficients, ductility ratio.and yield strength ratio of members. Strength degradation coefficients were newly proposed to explain the difference of inelastic behavior of members caused by spacing ratio of transverse steel and sectlon aspect ratio. The energy dissipation capacities calculated using the analytical model proposed in thls paper show a good agreements w~lh test results by an error of 10~20%.

• Journal of the Microelectronics and Packaging Society
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• v.8 no.3
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• pp.55-62
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• 2001

With a spread of BGA, CSP and fine pitch devices, the need of flatter surface finish in bare board is becoming more critical in solderability. The electroless Ni/Au plating has a solution of these needs and also has being spread to apply to surface finish for bare board in many electronic goods. But, the electroless Ni/Au plating had several issues such as Ni oxidation and phosphorous contents. Before this study, we studied on the effect of BGA solderability in electroless Ni/Au plating and chose some major factors such as the oxidation property of NiP plating and warpage of board. Firstly, we made test board with various plating conditions and improved the plating property through the improvement of NiP oxidation reducing P content. Also, we minimized the warpage of board with the improvement of inner layer structure and the analysis of warpage. For the evaluation of solderability, we analyzed the warpage of board and the plating property after mounting BGA on the board with optimizing conditions. The solder joint of BGA is investigated by SEM(Scanning Electronic Microscope) and OM(Optical Microscope). The composition of joint is used by EDS(Energy Dispersive Spectroscopy). We analyzed the fracture strength and mode by ball shear teser.

• Journal of the Korea Concrete Institute
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• v.25 no.4
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• pp.419-428
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• 2013

In this study, experimental research was carried out to evaluate the constructability and seismic performance of high strength R/C exterior beam-column joints regions, with or without the shear reinforcement, using high ductile fiber-reinforced mortar. Five specimens of retrofitted the exterior beam-column joint regions using high ductile fiber-reinforced mortar are constructed and tested for their retrofit performances. Specimens designed by retrofitting the exterior beam-column joint regions (BCJNSP series) of existing reinforced concrete building showed a stable mode of failure and an increased its maximum load-carrying capacity by 1.09~2.03 times in comparison with specimen of BCJNS due to the effect of enhancing dispersion of crack control at the time of initial loading and bridging of fiber from retrofitting new high ductile materials during testing. Specimens of BCJNSP series attained its maximum load carrying capacity by 0.92~0.96 times and increased its energy dissipation capacity by 1.62 times when compared to standard specimen of BCJC with a displacement ductility of 4.

• Journal of the Korea Concrete Institute
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• v.19 no.4
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• pp.401-409
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• 2007

The objective of this research is to provide better knowledge on the behavior of strong axis SRC column-RC beam joint, supported by experimental results, that can be broadly applicable to many structures. For this purpose, firstly literature reviews and field survey were made to classify the most commonly used for these types of joints. Then, experimental program was designed and performed including 6 SRC column-RC beam joint specimens designed with various joint details. Using the experimental results obtained from the quasi-static cyclic tests, structural performances of the joints such as hysteretic curves, maximum strength capacities, strength degradation beyond the maximum strength, ductilities, and energy dissipation capacities were investigated. Test results showed that specimens with wide beam shape (RCW-P, RCW-W, RCW-F) and T beam shape (RCT-W) showed better structural performances than the bracket type specimens (HBR-L, HBR-S). These specimens also revealed to have higher strength capacities than the nominal design strength. However, H beam bracket type specimens (HBR-L, HBR-S) need further study both analytically and experimentally to verify the reason for unexpected structural performances.

• The Journal of Engineering Geology
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• v.30 no.1
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• pp.43-57
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• 2020

The objective of this study was to evaluate the performance of high-strength lattice girders as a possible superior alternative to conventional steel arch ribs. For this purpose, the structural characteristics of supports were analyzed using numerical analysis, and their performance was evaluated using maximum bending load tests and tensile tests of the welded joint. According to the results of structural analysis, the optimum size of the upper and lower members and plates is 50 mm × 31.8 mm × 25.4 mm, demonstrating excellent functionality and economic efficiency. High-strength lattice girders of dimensions 55 mm × 30 mm × 20 mm and 85 mm × 30 mm × 20 mm, determined from bending load tests, are found to meet both the reference values and the target values of H-profiles 100 and 125. A review of the ratio of theoretical deflection to actual deflection shows that the high-strength lattice girder developed during this study meets fewer than five of the evaluation criteria for lattice girder deflections proposed by the Federal Railway Department of Germany. Finally, tensile test results reveal that the welded joint of the high-strength lattice girder at the main steel bar-auxiliary steel bar-plate junction exceeds the target value, indicating that the welded joint has sufficient stability.

• Journal of Veterinary Clinics
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• v.22 no.1
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• pp.21-25
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• 2005

This study was performed to assess therapeutic effect of the tibial plateau leveling osteotomy (TPLO) in dogs with experimentally transected cranial cruciate ligaments (CrCL). Nine healthy adult Beagle dogs were transected left CrCL under general anesthesia. The dogs were assigned to TPLO and non-TPLO control groups. The TPLO procedures for correcting the CrCL rupture in the left stifle of dogs were performed under sterile conditions. Before TPLO procedures, all dogs were screened by orthopedic and radiographic examinations. Dogs were lameness free for the previous three months, and when examined at the walk and trot on a hard surface, in a straight line and on a circle. Lateral and craniocaudal radiographs were done to confirm the soundness of the both knee joint in dogs and not detectable lesions were diagnosed. The dogs were intravenously injected with a 10 mci/kg of 99mTechnetium-methylene diphosphonate (99mTc-MDP) under general anesthesia. Scintigraphs were obtained using a large field of view gamma camera equipped a parallel-hole, low-energy about 3 hours after intravenous injection of 99mTc-MDP. Before CrCL transection and 4, 8, and 12 weeks after the procedures, scintigraphy were conducted. Bone uptake of the left stifle joint increased after the procedures in all dogs. When the bone uptake from the TPLO procedure was compared with that of the control, there was a significant difference (p < 0.05). At 12 weeks after the TPLO procedure, the dogs showed normal anatomical posture and gait. It is concluded that TPLO procedure was effective in reconstruct of the stifle joint in dogs with CrCL rupture.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.2
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• pp.346-351
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• 2003

The current studies investigated the therapeutic effects of Ephedra sinica Stapf (ES) herb-acupuncture on the inflammatory responses of rat arthritic joint, which was induced by the intradermal injection of heat-killed Mycobacterium tuberculosis emulsified in squalene to the base of the tail. The measurements of body weight and articular index were exploited as the assessment methods addressing arthritic symptoms, and the expression profiles of cytokines such as TNF-α, IL-1β and IL-6 in the rat joint were analyzed using RT-PCR. The articular indexes of arthritic rats were significantly restored after the treatment with ES herb-acupuncture. Although the clinical symptoms of arthritic rats were apparently alleviated by the ES treatments, their body weights were not recovered. It maybe due to the weight-loss and energy enhancement effects of ES extracts. The expression of TNF-α, IL-1β and IL-6 genes, which were highly stimulated in the knee joints of arthritic rats, were restored to the levels of normal rats after the ES treatment. The therapeutic effect of ES herb-acupuncture was not observed in ES-treated, non-acupoint arthritic group as a sham control. The ES herb-acupuncture into an acupoint ST36 was found to be effective in alleviating the arthritic symptoms in adjuvant-induced arthritis rats as regards the body weight, joint appearance and the expression profiles of inflammatory cytokines.

• Journal of the Korea Concrete Institute
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• v.24 no.2
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• pp.147-156
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• 2012

In recent years, many high-rise buildings have been constructed in irregular structural system with inclined columns, which may have effect on the structural behavior of beam-column joints. Since the external load leads to shear and flexural forces on the inclined columns in different way from those on the conventional vertical columns, failure mode, resistant strength, and ductility capacity of the inclined column-beam joints may be different than those of the perpendicular beam-column joints. In this study, six RC inclined beam-column joint specimens were tested. The main parameter of the specimens was the angle between axes of the column and beam (90, 67.5, and 45 degree). Test results indicated that the structural behavior of conventional perpendicular beam-column joint was different to that of the inclined beam-column joints, due to different loading conditions between inclined and perpendicular beam-column joints. Both upper and lower columns of perpendicular beam-column joints were subjected to compressive force, while the upper and lower columns of the inclined beam-column joints were subjected to tensile and compressive forces, respectively.

• Journal of the Korea Concrete Institute
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• v.25 no.2
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• pp.201-207
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• 2013

When hot weather concrete is utilized, the cooling methods of cooling pipe, liquid nitrogen, ice, etc., are used to prevent the poor consistency and cold joint due to high temperature. These methods, however, spike the production cost and energy consumption, and make quality control difficult. Among these methods is one that involves the use of a retarder. Although economical, retarder is caused difficulty of retarded hardening and setting time control due to inaccurate weighing and poor working condition. Therefore, how to make a tablet for hot weather concrete, as with the existing pharmacy and foods, is discussed in this study, including the following items: mortar setting time, flow test by elapsed time, physical and mechanical properties of concrete. As a result, gluconic acid is superior to lignosulfonic acid and the possibility of using them for such purpose without quality degradation was confirmed in this study, when retarder is tabletting.