• Journal of Welding and Joining
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• v.32 no.1
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• pp.15-21
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• 2014

FCAW(Flux Cored Arc Welding), SAW(Submerged Arc Welding), EGW(Electro Gas Welding), and three-pole SAW are applicable in manufacturing the offshore wind tower. In this paper, mechanical properties of these welded-joints for TMCP steels were evaluated in all above welding processes. The tensile strength of welded-joints for all the welding methods satisfied the standard guideline (KS D 3515). No cracking on weldment was found after the bending test. Changes of weldedments hardness with welding processes were observed. In a weld HAZ (heat-affected zone), a softened HAZ-zone was formed with high heat input welding processes (SAW and EGW). However, the welded-joint fractures were found in the base metal for all cases and small decrease in welded-joint strength was caused by a softened zone. The multi-pole SAW welds exhibited similar mechanical properties comparing to the one with one-pole SAW process.

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.3
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• pp.270-279
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• 2003

Parametric studies have been conducted into the variability of the factors affecting the ultrasonic testing applied to weldments. The influence of ultrasonic equipment, transducer parameters, test technique, job parameters, defect type and characteristics on reliability far defect detection and sizing was investigated by experimentation. The investigation was able to build up substantial bank of information on the reliability of manual ultrasonic method for testing weldments. The major findings of the study separate into two parts, one dealing with correlation between ultrasonic techniques, equipment and defect parameters and inspection performance effectiveness and other with human factors. Defect detection abilities are dependent on the training, experience and proficiency of the UT operators, the equipment used, the effectiveness of procedures and techniques.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.631-637
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• 2005

This paper presents a stiffness analysis method for a low-DOF parallel manipulator, which takes into account of elastic deformations of joints and links. A low-DOF parallel manipulator is defined as a spatial parallel manipulator which has less than six degrees of freedom. Differently from the case of a 6-DOF parallel manipulator, the serial chains in a low-DOF parallel manipulator are subject to constraint forces as well as actuation forces. The reaction forces due to actuations and constraints in each limb can be determined by making use of the theory of reciprocal screws. It is shown that the stiffness model of an F-DOF parallel manipulator consists of F springs related to the reciprocal screws of actuations and 6-F springs related to the reciprocal screws of constraints, which connect the moving platform to the fixed base in parallel. The $6{times}6$ stiffness matrix is derived, which is the sum of the stiffness matrices of actuations and constraints. The six spring constants can be precisely determined by modeling the compliance of joints and links in a serial chain as follows; the link can be considered as an Euler beam and the stiffness matrix of rotational or prismatic joint can be modeled as a $6{times}6$ diagonal matrix, where one diagonal element about the rotation axis or along the sliding direction is zero. By summing the elastic deformations in joints and links, the compliance matrix of a serial chain is obtained. Finally, applying the reciprocal screws to the compliance matrix of a serial chain, the compliance values of springs can be determined. As an example of explaining the procedure, the stiffness of the Tricept parallel manipulator has been analyzed.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.323-334
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• 2008

This experiment was carried out to analyze for pesticide residues in 17 different types of the special of geographical indication. We purchased 3 cereal grains, nuts and seeds, 3 fruits, 8 vegetables, mushrooms and other plants (Korean medicines) mainly at the agricultural cooperative's joints markets. Total 209 pesticides including multi-analysed pesticides (204) and single-analysed pesticides (5 ; acephate, methamidophos, monocrotophos, omethoate, vamidothion) were analysed with a GC/MS/MS, an HPLC/UVD (PDA) and a GC/FPD. No. 83 method and single-analysed method (Screening of multi-pesticide residue in the special products of geographical indication) of Korea Food Code was selected for validation in recovery and interferences of matrice. The results were as follows: among the selected 17 the special products, the residual pesticides were detected in 8 types of the special products (40 in 302 samples, detection ratio; 13.2%). All of the samples were not detected over MRLs, but tebuconazole, procymidone and isoprothioran were detected with considerable high frequency. These results could be used as KFDA official methods for the analysis of pesticide residues in foods and reference data will be provided to the related institutions.

• Korean Journal of Environment and Ecology
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• v.33 no.6
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• pp.734-747
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• 2019

This study surveyed the visitors to the Seoseokdae Peak of the Mudeungsan National Park, to analyze the factors that affected user behavior, perception of the National Park, and satisfaction with the visit and establish the strategy for the management of the Mudeungsan National Park. The analysis result showed that Gwangju residents (78.1%) accounted for the majority of the visitors to the Seoseokdae Peak and that the Mudeungsan National Park showed the attributes of both mountain type and suburb type. Most visitors (91.2%) perceived that columnar joints, including the Seoseokdae Peak, possessed the largest resource value in the Mudeungsan National Park, and the visitors showed concern over the potential damage to vegetation in the Seoseokdae Peak as the result of the overcrowded visitors. Over half of the visitors showed a positive response to the measures like partially restricted access or detour of mountain path to preserve and restore the Seoseokdae Peak. The total visitors and the regional visitors (residents of Gwangju, Damyang, and Hwasun), indicated that the facility management aimed at facilitating visitor experience affected the most on the satisfaction with park management. Moreover, the regional visitors answered that the visit management to control disorder and overcrowding would increase satisfaction. The result of the importance-satisfaction analysis showed a difference between the total visitors and the regional visitors in needed improvements as the total visitors believed that "amenities and information facilities" should be improved while the regional visitors believed that the focus should be on the "prevention of illegal and disorderly behaviors" and the "amenities and information facilities."

• Journal of Physiology & Pathology in Korean Medicine
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• v.29 no.4
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• pp.337-346
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• 2015

Sprain is the injury of meridian-muscle, and is caused by qi and blood obstruction or regional stagnation of qi and blood. So we take the channel points where pain flows. If we take the locations that feel pain, those locations are treatments points and ashi points. So we searched over the ashi points appearing on the patients with wrist sprain. Ashi points appeared on LI5, TE4, SI5 around wrist joints, LI10, LI11, LU6 around elbow joints, LI14, LU3, LU4, PC2 around upper arm. Also, ashi points appeared much on ST17, KI23, PC1, SP18, ST18 around thoracic region, and, on BL15, BL44, BL13 around anterior and thoracodorsal region, in order stated. Ashi points of the highest frequency appeared on LI14 around upper arm, and on LI5, TE4 around wrist joint, and SI5, ST17, KI12, PC1, SP18 appeared with second highest frequency. And ashi points on elbow points and thoracodorsal region appeared with the same frequency. Therefore, it is possible for us to know that the pain location appears in order of upper arm, anterior thoracic region, elbow joint region, and, thoracodorsal region, in treating wrist joints. There was a tendency that pain and movement disturbance recovered more quickly, depending on the pain reduction, as we found out the ashi points closely from stagnated qi and blood caused by wrist arthritis, and relaxed the stiff location. Rubbing treatments in treating pain ashi points is considered to play an important role to reduce pain effectively, so it is necessary to make a further study.

• 한국HCI학회:학술대회논문집
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• 2006.02b
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• pp.705-713
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• 2006

우리나라 지역방송은 방송의 공익성 강화를 위한 방송프로그램의 '지역성 구현'과 규모의 경제를 이루기 위한 '방송시장의 확대'라는 두 가지 지역방송 발전정책을 추진하고 있다. 그 정책실천의 하나로서 인접한 방송권역의 지역방송사(국)들 간에 방송프로그램의 제작과 편성에 있어서 다양한 교류와 협력을 확대해나가는 권역화의 과정이 있다. 그러나 그 결과물인 권역공동제작 방송프로그램에 대한 내용면 그리고 사업면의 평가 및 검증은 아직까지 이루어지지 않았다. 따라서 본 연구에서는 지역방송 간의 제작 편성교류를 통해 제작된 방송프로그램들이 내용면에서 얼마나 이상적인 지역성을 구현하고 있는지, 그리고 사업면에서 얼마나 지역시청자에게 소구력이 있는지를 평가해보고자 한다. 이 평가의 도구로써는 지역 텔레비전 프로그램 별 지역성 지수와 사업성 지수인 방송시청률을 이용한다. 다양한 지역방송프로그램이 얼마나, 어느 정도 지역성과 방송시청률을 담보하고 있는지 평가하기 위한 하나의 평가척도를 제시하고 그에 따라 각 프로그램의 지역성 정도를 구체화하고자 한다. 지역방송의 권역화 과정에서 '이상적인 지역성'의 구현과 '사업적인 안정'의 실현은 상호배타적인 실천과제가 아니라 동시에 균형적으로 추진되어야 할 중요한 목표인 것이다. 따라서 권역화 과정에 나타나고 있는 다양한 방송프로그램들을 이 두 기준에 맞추어 평가하는 것은 지역방송의 공적 가치와 사업적 토대를 동시에 고려해보는 중요한 의미를 가지게 된다.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.4
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• pp.539-545
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• 2012

To evaluate of the ultrasonographic changes in hemiplegic and unaffected knee joints of hemiplegic ambulators with recent onset stroke. Twenty patients (40 knees) with prevalence duration of 14-39 weeks (mean 24.70 weeks) after a stroke insult were included. All participants were walking independently without leg dragging, had no previous knee injury. There were significant differences in intercondylar cartilage thickness and pes anserinous tendinopathy (PAT) between hemiplegic and unaffected knees (p<0.05). There were no differences in cartilage thickness of medial condyle and lateral condyle, patellar tendinitis/bursitis, suprapatellar effusion, synovitis, joint space narrowing, and Baker's cyst of ultrasonographic findings and x-ray findings in hemiplegic knee compared to the control except PAT (p<0.05). In hemiplegic knee, medial or lateral condylar cartilage thickness was significantly correlated with body weight, intercondylar cartilage thickness, and PAT (p<0.05). PAT was significantly correlated with Brunnnstrom stage and condylar cartilage thickness (p<0.05). Knee pain was significantly correlated with lateral condylar cartilage thickness (p<0.1). The hemiplegic knee had more ultrasonographic abnormalities including PAT and more cartilage thickness preservation in patient with recent onset stroke. Intraarticular sonographic findings including cartilage thickness was significantly correlated with extraarticular findings including PAT and a symptom of knee pain.

• The Journal of Engineering Geology
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• v.19 no.3
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• pp.351-363
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• 2009

Two orthogonal joint sets develop well only in sandstone beds in the sandstone-mudstone sequences of Gumi and Dasa outcrops within Cretaceous Gyeongsang Basin. And various joint data are similar in the beds of the same thickness in both outcrops, meaning that the joint sets were homogeneously produced by extensional deformation in the same regional stress field. Most of joints in the sandstone beds are orthogonal to, and confined by bed boundaries, which are believed to be formed by hydrofracturing during consolidation after burial. Two orthogonal joint sets are considered to be almost coeval on the basis of mutual abutting relationship which makes up fracture grid-lock and a product of rapid switching of ${\sigma}_2$ and ${\sigma}_3$ axes with constant ${\sigma}_1$ direction oriented to vertical. The joint sets in the sandstone beds show planar surfaces, parallel orientations and regular spacing, with joint spacing linearly proportional to bed thickness. The spacing distributions of the joints seem to correspond to log-normal to almost normal distribution in most of the beds. But multilayer joints do not display regular spacing and dominant size. Either joint set in this study is characterized by a high level of joint density and a saturated spacing distribution as indicated by the mode/mean ratio values and the Cv(coefficient of variance) values. Joint aperture tends to increase with the vertical length of the joints controlled by bed thickness.

• The Journal of Engineering Geology
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• v.18 no.4
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• pp.459-470
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• 2008

Types of slope failure related to cut slope stability are interpreted through case analyses, and also factors affecting structurally controlled instability investigated, which are developed by geologic structures along a national road No. 25 across the Cheongwon and Boeun-Guns, Chungbuk. Engineering properties such as orientation, persistence, roughness and uniaxial compressive strength of joints are analyzed by square-inventory method in three areas with well-preserved outcrops. The study area is located in Ogcheon folded bet, and are composed of quartz-schist and quartzite in the Midongsan Formation and phyllite in the Ungyori Formation. Flexural beds by folding, schistosity and cleavage besides joints are developed due to slight metamorphism. Various types of joints developed by folding are formed such as strike-parallel, strike-perpendicular, wedge and wrench joint sets by both initially regional and later superposed folding. Factors of slope instability are created by crossing the orientations of joint, cleavage, bedding and slope one another. In the case that the orientation of a slope is coincident with one of beds, factors causing large-scale failure including plane failure are increased greatly. Also in the region that orientations of the slope and bed are crossed each other at high angle, only local and minor failures are shown in the slope.