• Journal of Oral Medicine and Pain
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• v.34 no.1
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• pp.103-114
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• 2009

This study was designed to evaluate the Temporomandibular Disorders(TMD) with Tension-Type Headache(TTH) by age. Patients with TMD and/or TTH visited the Department of Oral Medicine, Kyung Hee University Dental Hospital were recruited to this study. Experimental group(n=170) is composed of TMD with TTH and control group(n=222) is composed of TMD without TTH. Evaluation list was pain quality, pain intensity, pain laterality, pain increase by routine physical activity and then it was analyzed statistically. The results were as follows ; 1. In the control group, pain quality was not significantly different by age. But, in the experimental group, pain quality was significantly different by age(p=0.042). 2. In the control group, pain intensity was significantly different by age(p=0.000). And, in the experimental group, pain intensity was significantly different by age(p=0.004). 3. In the control group, pain laterality was not significantly different by age. And, in the experimental group, pain laterality was not significantly different by age. 4. In the control group, pain increase by routine physical activity was not significantly different by age. And, in the experimental group, pain increase by routine physical activity was not significantly different by age. Therefore, it is considered that not temporomandibular disorder patients without tension-type headache but temporomandibular disorder patients with tension-type headache was influenced by age in the pain quality.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.11 no.1
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• pp.1-10
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• 2016

Objectives : The purpose of this study was to review the effectiveness of Chuna manual therapy for the treatment of tension type headache(TTH). Methods : All processes were independently carried out by three investigators. Literature search was performed in 3 databases(pubmed, OASIS, NDSL) from their inception to May 2016. Searched reports was twice excluded for title, abstract and body. And then, data extract and analysis was done before assessing risk of bias by Cochrane Handbook. Results : 11 RCT were included. Generally, Fascia Chuna therapy and Chuna spine & joint manipulation therapy were used for TTH. Except for 1 report, Chuna manual therapy was shown to be effective in treating TTH. In assessing risk of bias, because of the characteristic of intervention, blinding of participants was high risk of bias in most reports. Conclusions : Chuna manual therapy was shown to be effective in treating TTH. In korea, better designed trials with high quality is needed from now on.

• Journal of Korean Society of Steel Construction
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• v.8 no.3 s.28
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• pp.139-150
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• 1996

H/T(High Tension) bolt is generally being used in joining the members of steel structure. It has some difficulties in management such as an adequate fastening force and a selection of proper instrument for fastening. T/S(Torque Shear Type High Tension) bolt which is more convenient and easier than H/T bolt in quality control has recently been developed. T/S bolts are produced and widely used these days in domestic, but those have not a detail regulation for their on. Those are only being used according to the specification for the H/T bolts. In this study, we tried to confirm the soundness of T/S bolts by the fatigue test of the modified specimens. First, we measured the reduction rate of the initial axial force with time at bolts. Second, we investigated the slip forces of bolts when the test specimen is loaded in tension. Third, we implemented the fatigue tests. During the test, we measured the variation of the axial forces of bolts under the cyclic loading. Finally, we compared and analyzed the fatigue behavior of H/T and T/S bolt, by S-N curve diagrams that are obtained in this study.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.2
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• pp.102-108
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• 2016

Headache disorders, one of most common disease in general population, have been developed according to many versions of international classifications. The primary headaches are those in which no consistently identified organic cause can be determined. It is divided into the following categories: (1) migraine, (2) tension-type headache, (3) cluster headache and other trigeminal autonomic cephalalgias, (4) other primary headaches. This review described a diagnosis of primary headache disorders based on International Classification of Headache Disorders (ICHD)-3 beta criteria.

• Advances in Computational Design
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• v.4 no.4
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• pp.343-365
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• 2019

Among the themes related to earthquake countermeasures at construction sites, those for tower cranes are particularly important. An accident involving the collapse of a crane during the construction of a skyscraper has serious consequences, such as human injury or death, enormous repair costs, and significant delays in construction. One of the causes of deadly tower crane collapses is the destruction of the site joints of the tower crane mast. This paper proposes a new design method by static elastoplastic finite element analysis using a supercomputer for the design of the end plate-type tensile bolted joints, which are generally applied to the site joints of a tower crane mast. This new design method not only enables highly accurate and reliable joint design but also allows for a design that considers construction conditions, such as the introduction of a pre-tension axial force on the bolts. By applying this new design method, the earthquake resistance of tower cranes will undoubtedly be improved.

• Steel and Composite Structures
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• v.43 no.1
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• pp.19-30
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• 2022

The static strength and fatigue crack resistance of the aircraft skin structures depend on the materials used and joint type. Most of the commercial aircraft's skin panel structures are made from aluminium alloy and carbon fibre reinforced epoxy. In this study, the fatigue resistance of four joint configurations (metal/metal, metal/composite, composite/composite and composite/metal) with riveted, adhesive bonded, and hybrid joining techniques are investigated with experiments and finite element analysis. The fatigue tests were tension-tension because of the typical nature of the loads on aircraft skin panels susceptible of experimenting fatigue. Experiment results suggest that the fatigue life of hybrid joints is superior to adhesive bonded joints, and these in turn much better than conventional riveted joints. Thanks to the fact that, for hybrid joints, the adhesive bond provides better load distribution and ensures load-carrying capacity in the event of premature adhesive failure while rivets induce compressive residual stresses in the joint. Results from FE tool ABAQUS analysis for adhesive bonded and hybrid joints agrees with the experiments. From the analysis, the energy release rate for adhesive bonded joints is higher than that of hybrid joints in both opening (mode I) and shear direction (mode II). Most joints show higher energy release rate in mode II. This indicates that the joints experience fatigue crack in the shear direction, which is responsible for crack opening.

• Economic and Environmental Geology
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• v.9 no.2
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• pp.85-106
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• 1976

The Bulgugsa acidic igneous rocks of the late Cretaceous age are largely distributed in Busan area, which is located in the southeastern corner of the Korean Peninsula. These igneous rocks comprise in ascending order, felsite, dacitic-rhyolitic welded tuffs, granite porphyry and granitic rocks. The former three members represent the early phase of volcanic activities, so that they are named as Jangsan volcanic rocks. The granitic rocks consist of granodiorite, hornblende biotite granite, Kumjongsan granite, fine grained granite, and Daebyen granite, represent the late phase of igneous activities. The Kumjongsan grainte, the largest pluton of the granitic mass, emplaced between two great vertical faults trending NNE. New chemical analyses of 33 rock samples of these acidic rocks are given. Their chemical compositions are generally similar to those of the late Mesozoic acidic igneous rocks of the northern Ashio mountains, and C-Zone granite group of the Ogcheon geosyncline, with their characteristic variation trends of several oxides. Their chemical compositions also show that $Al_2O_3$ is high value, and differentiation index is high, too. Systematically developing joints in Kumjungsan granite are divisible into two types at least. One is the NS-N $20^{\circ}E$ trendirig, $85^{\circ}{\sim}90^{\circ}$ dipping type of joint system which coincides with the trends of distribution of the granite mass and the dikes intruding this granite. Joints of this type may be cooling joints generated as tension cracks. The other is the $N60^{\circ}{\sim}70^{\circ}W$ or $N40^{\circ}{\sim}60^{\circ}E$ trending type of joint systems. It is considered that. joints belonging to this type may be shear joint occurring under the state of south-north tectonic couple acting at the east and west side of the granite mass. Igneous activities of the the Bulgugsa acidic igneous rocks in Busan area was taken place as. follows, formation of the magma reservoir, eruption and intrusion of felsite, consolidation of vents. and increasing vapor pressure in magma reservoir, eruption of pyroclastic flows, caldera collapse, intrusion of granite porphyry, and intrusion of granitic rocks at the latest stage.

• Journal of Oral Medicine and Pain
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• v.32 no.1
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• pp.113-120
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• 2007

Although most cases of tension-type headache(TTH) are myogenic headache, in some cases, arthralgia appears, such as the disorder of the temporamandibular joint. This study is designed to compare the clinical patterns of arthralgia to those of myalgia, when both symptoms are co-existing. Among 167 patients who visit our clinic during a certain period, whose chief complaint was TTH, 18 patients were the arthralgia group, 50 patients were the myalgia group, and 99 patients who have both arthralgia and myalgia were the arthromyalgia group. Three groups were asked to answer the questionnaires about their age, gender, and oral parafunction such as bruxism or clenching. Then we gathered statistics on the data from the accomplished questionnaires. 1. There was statistical significance in age among the three groups(p=0.02). 2. There was no statistical significance in sex and oral parafunction among the three groups. 3. There was statistical significance the myalgia group was older than the arthromyalgia group(p<0.03). The results of the study show that as patients become older, TTH with myalgia happens more frequently than TTH with arthralgia and myalgia does.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5566-5571
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• 2012

Block shear failure is one of limit states, and demands great caution in designing the tension member or connection joint of steel structures. From many studies and design specification, it is shown that the effect of the bolted connection type on the block shear failure was not considered. In order to investigate the effect of the bolted connection type(bearing type connection and slip critical connection) on the mode/strength of the block shear failure, tensile experiment is conducted in this study. Differences about the failure mode according to the design specification, bearing type connection, and slip critical connection are proposed from the analysis of test results. The variation of the block shear failure strength due to the frictional force in the slip critical connection is also investigated.

• Structural Engineering and Mechanics
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• v.56 no.4
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• pp.667-694
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• 2015

The suspended dome system is a new structural form that has become popular in the construction of long-span roof structures. Suspended dome is a kind of new pre-stressed space grid structure that has complex mechanical characteristics. In this paper, an optimum topology design algorithm is performed using the enhanced colliding bodies optimization (ECBO) method. The length of the strut, the cable initial strain, the cross-sectional area of the cables and the cross-sectional size of steel elements are adopted as design variables and the minimum volume of each dome is taken as the objective function. The topology optimization on lamella dome is performed by considering the type of the joint connections to determine the optimum number of rings, the optimum number of joints in each ring, the optimum height of crown and tubular sections of these domes. A simple procedure is provided to determine the configuration of the dome. This procedure includes calculating the joint coordinates and steel elements and cables constructions. The design constraints are implemented according to the provision of LRFD-AISC (Load and Resistance Factor Design-American Institute of Steel Constitution). This paper explores the efficiency of lamella dome with pin-joint and rigid-joint connections and compares them to investigate the performance of these domes under wind (according to the ASCE 7-05), dead and snow loading conditions. Then, a suspended dome with pin-joint single-layer reticulated shell and a suspended dome with rigid-joint single-layer reticulated shell are discussed. Optimization is performed via ECBO algorithm to demonstrate the effectiveness and robustness of the ECBO in creating optimal design for suspended domes.