• Korean Journal of Applied Biomechanics
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• v.23 no.4
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• pp.327-333
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• 2013

The purpose of this study was to investigate the effects of different types of attentional focus(internal focus vs. external focus) on the dart throwing mechanics. Seven expert dart throwing athletes were assigned to an internal focus group and other seven athletes were assigned to an external focus group. Each group was asked to throw dart either under verbal instruction or without instruction. During dart throwing, accuracy(radial error), consistency(bivariate variable error), dart velocity, acceleration, elbow joint ROM, elbow joint angular velocity, EMD(electromechanical delay), iEMG of biceps brachii and triceps brachii, and CI(coactivation index) were collected and analyzed. Nither instruction type nor instruction itself affected in accuracy and consistency. However, in dart velocity and acceleration, there was an interaction between instruction and attentional focus types. Velocity and acceleration increased in the internal condition, where as they decreased in the external condition. The ROM of elbow joint did not affected by instruction and attention type. However, similar to dart velocity and acceleration, angular velocity increased in internal focus group, while it decreased in external focus group. EMG showed no difference with any condition. In conclusion, internal focus is better than external focus for dart throwing.

• The Journal of the Korean dental association
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• v.38 no.6 s.373
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• pp.549-557
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• 2000

ㆍPurpose: This study was performed to investigate the initial conservative treatment for TMD patients using careful counselling and medication prospectively. ㆍMaterials and Methods: Careful counselling and medication were performed in 51 TMD patients and 27 patients had follow-up check 2 months or more. Diagnosis of TMD was based on medical history and, physical and radiographic examination. TMD included masticatory disorder, internal derangement, degenerative joint disease, inflammatory joint disorder. and problems resulting from extrinsic trauma. All patients had chief complaints of TMJ pain, mouth-opening limitation. joint noise, and/or referred pain. We counselled and explained to the patient about the pathogenesis, etiologic factors, diagnosis and treatment plan for abut 10 minutes. We prescribed nonsteroidal anti-inflammatorv analgesic(Somalgen) and amitriptyline 10mg per day for 2 weeks. We informed the patient of the attention sheet and taught self-exercise of jaw. The patient were assessed by answering the questionnaire of subjective evaluation of TMD & maxillofacial pain. Questionnaire of an activity limitation. Questionnaire of a jaw function, and Questionnaire for the evaluation of TMD. ㆍResults: In questionnaire for the evaluation of TMD, 88.5% of 26 patients answered that the treatment was efficacious. 71.4% of 21 patients answered no problem in everyday life. There were significant differences between pretreatment and final follow-up in the evaluation of the subjective pain in the following sections: opening widely, chewing, resting, morning, masticatory muscle, and temporal portion(SAS program, paired T-test, P = 0.05). ㆍConclusions: Considerate counselling and proper medication could be significantly effectve in the initial treatment of TMD.

• Steel and Composite Structures
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• v.22 no.5
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• pp.1019-1038
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• 2016

The use of high-strength concrete (HSC) in precast concrete segmental bridges (PCSBs) can minimize the superstructure geometry and reduce beam weight, which can accelerate the construction speed. Dry joints between the segments in PCSBs introduce discontinuity and require special attention in design and construction. Cracks in dry joints initiate more easily than those in epoxy joints in construction period or in service. Due to the higher rupture strength of HSC, the higher cracking resistance can be achieved. In this study, shear behavior of dry joints in PCSBs was investigated by experiments, especially focusing on cracking resistance and shear strength of HSC dry joints. It can be concluded that the use of HSC can improve the cracking resistance, shear strength, and ductility of monolithic, single-keyed and three-keyed specimens. The experimental results obtained from tests were compared with the AASHTO 2003 design provisions. The AASHTO 2003 provision underestimates the shear capacity of single-keyed dry joint C50 and C70 HSC specimens, underestimates the shear strength of three-keyed dry joint C70 HSC specimens, and overestimates the shear capacity of three-keyed dry joint C50 HSC specimens.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.3 no.2
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• pp.65-68
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• 2010

Acromio-clavicular (AC) joint cyst have been reported in small series of the orthopedics literature in association with extensive rotator cuff tear, pseudotumor, infection of the shoulder or chondrocalcinosis. Authors experienced one case of AC joint cyst with rotator cuff re-tear after arthroscopic rotator cuff repair, clinicians may need pay attention to AC joint bulging or mass lesion after arthroscopic rotator cuff repair as an important sign to check follow-up imaging study for the cuff integrity. Especially, ultrasonography is recommended for this follow up study, because it is simple to be operated, economic, easily accessible.

• Journal of the Korean Professional Engineers Association
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• v.42 no.5
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• pp.32-36
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• 2009

This project located in IFEZ(Incheon Free Economic Zone) is the first central heating and cooling type for high-rise residential building in korea. The design was performed as the joint venture between Cosentini from U.S.A and wooowon, and our design concept was to save energy. LEED application from USGBC is going on in progress for the first residential building in korea. Careful attention was paid from schematic design for not a durability of structural and architectural, but also durability and safety of M.E.P.

• Journal of the Korean Geotechnical Society
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• v.23 no.11
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• pp.67-76
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• 2007

The characteristics of rockfall are determined by virtually all factors and conditions e.g. the physical figure of the slope such as inclination, height, roughness, the elemental figure of the slope such as vegetation and material deposited, and the shape and weight of the rockfall itself. Although it is one of the major factors to be considered in rockfall simulation, little attention has been given to the weight of the rockfall. And, since the size of the rockfall is dominated by joint spacing, the distribution of the rockfall block weight can be predicted as a function of the joint spacing. In this study, the weight distribution of rockfall was estimated by using the method of volumetric joint count, $J_{\nu}$, based on joint spacing, and $RQD-J_{\nu}$. The results indicate that the weight distributions were analogous in two methods, and the distribution was to be $75.3{\sim}76.7%$ for 200 kilograms or lesser, $15.0{\sim}16.6%$ for $200{\sim}400$ kilograms, and $6.7{\sim}9.7%$ for 400 kilograms or more, which show good matches with the actual on-site weight distribution. Therefore, the weight distribution of rockfall suggested in this paper is able to be considered as appropriate data for rockfall simulation.

• Journal of Korean Foot and Ankle Society
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• v.13 no.2
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• pp.142-145
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• 2009

Purpose: The aim of this study was to retrospectively evaluate the clinical and radiological results of the first metatarsophalangeal joint arthrodesis with two crossed screws fixation. Materials and Methods: We treated 23 patients (24 cases) with arthrodesis of the first metatarsophalangeal joint using two crossed screws fixation between December 2000 and May 2005. There were 3 male patients and 20 female patients. Ages ranged from 28 to 74 years (mean, 50 years). Follow-up ranged from 4.1 to 8.2 years (mean, 6.5 years). The American Orthopaedic Foot and Ankle Society (AOFAS) score and their satisfaction was evaluated clinically, foot anteroposterior and lateral radiograph, radiologically. Results: Of the 24 cases, 6 had surgery for dorsal plate and screws fixation because of failure to acquire firm fixation with two crossed screws fixation. All 6 cases acquired bony union. Fusion of the hallux first metatarsophalangeal joint occurred in 16/18 cases (89%). Nonunion occurred in 2 cases (11%) and was asymptomatic. At last follow-up, hallux valgus angle ranged from 11 to 25 degrees(mean, 17.7 degrees), dorsiflexion ranged from 15 to 25 degrees (mean, 22 degrees).The mean preoperative AOFAS score of 37 points(range, 28 to 45 points) improved to a mean of 77 points (range, 65~90 points) postoperatively. The result of the procedure as rated subjectively by the patient was excellent for 5 cases, good for 11 cases and fair for 2. Conclusion: Comparatively, the arthrodesis of the first metatarsophalangeal joint with crossed screws fixation showed a satisfactory clinical results, we thought that require technical attention for firm fixation in operation.

• Earthquakes and Structures
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• v.12 no.2
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• pp.237-250
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• 2017

There has been increasing attention in many countries on seismic retrofit of old fashioned RC structures in recent years. In such buildings, the joints lack transverse reinforcement and suffer inadequate seismic dimensional requirements and the reinforcement is plain bar. The behavior of the joints is governed by sliding of steel bars and diagonal shear failure is less influential. Different methods to retrofit beam-column joints have been proposed in the literature such as wrapping the joint by FRP sheets, enlargement of the beam-column joint, and strengthening the joint by steel sheets. In this study, an enlargement technique that uses external prestressed cross ties with steel angles is examined. The technique has already been used for substructures reinforced by deformed bars and has advantages such as efficient enhancement of seismic capacity and lack of damage to the joint. Three reference specimens and two retrofitted units are tested under increasing lateral cyclic load in combination with two levels of axial load. The reference specimens showed relatively low shear strength of 0.150${\surd}$($f_c$) and 0.30${\surd}$($f_c$) for the exterior and interior joints, respectively. In addition, relatively brittle behavior was observed and large deformations extended into the panel zone of the joints. The retrofit method has increased ductility ratio of the interior beam-column joints by 63%, and energy dissipation capacity by 77%, relative to the control specimen; For external joints, these values were 11%, and 94%. The retrofit method has successfully relocated the plastic joints far from the column face. The retrofit method has improved shear strength of the joints by less than 10%.

• Journal of Information Technology and Architecture
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• v.11 no.1
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• pp.11-23
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• 2014

Kill Chain is getting attention due to North Korea's recent nuclear test and missile launches and has emerged the need for an early build up. In order to build a materialized kill chain, you should review the unique kill chain to support operations effectively using various sensors and striking weapon system. Especially, you need a suitable network to reduce a reaction time against the enemy attack under joint operations environment etc. Currently there are many communication ways(e.g. data link, voice, video and text message) used in operations through satellite, wired and wireless and so on. Now, this paper contains analysis on various means for target information exchange which are used in the kill chain. And appropriate network of the kill chain for target information transmission is addressed to confirm feasibility of its alternatives, which is developed using AHP(Analytic Hierarchy Process). Finally, this paper is suggesting network and means of its building up for target information transmission of kill chain which can be implemented under the situation of joint battle field.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.3926-3933
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• 2015

The purpose of this study was to determine the factors associated with duration of postoperative delirium following orthopedic joint surgery. This study included 266 patients who underwent orthopedic joint surgery at a single university hospital between January 2012 and February 2014. Patients were divided into two groups according to the duration of delirium: the transient (${\leq}2$ days) and prolonged (>3 days) delirium groups. Of the 266 patients, 137 (52%) developed prolonged delirium. Incidence of pre-existing dementia and history of stroke were significantly higher in the prolonged delirium group than in the transient delirium group. In a multivariate regression model, pre-existing dementia and history of stroke were associated with increased duration of delirium. Our findings suggest that medical practitioners should pay special attention to the prevention and management of postoperative delirium in patients who have dementia or stroke and undergo orthopedic joint surgery.