• Journal of Korean Society of Steel Construction
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• v.22 no.3
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• pp.271-280
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• 2010

This study was programmed to fabricate a beam-to-column connection that is limited to a steel-welded moment connection with full-scale members, using SN steel. A cyclic seismic test was conducted of the nine specimens that were fabricated by choosing the test variable for the weld access hole geometry, connection design method, and RBS. From the test results, failure modes, the moment-drift behavior, and the strain distribution were provided. From the specimen material properties, the beam's nominal plastic flexural capacity and classified qualified connection as a special moment flame were calculated. By analyzing the skeleton part and the baushinger part, a range of strength-raising effects, and deformation ratios were provided, with which the seismic performance of the specimens were evaluated. The test results showed that the specimens eliminated their weld access holes that demonstrated higher seismic performance than the specimens' existing weld access holes, and that the WUF-W connection that was reinforced by the supplemental fillet weld around the shear tap that was fastened by five bolts demonstrated superior seismic performance.

• Science of Emotion and Sensibility
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• v.8 no.4
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• pp.423-433
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• 2005

The computer hardware development has provided many chances of emergence between art and technology. In many cases today's interactive artworks cannot be completed without audience's participation. The interactive production process with technical supplementation can be celled feedback. Mr. Nam Jun Paik showed 'Participant TV' that interacts with audience's response in real time. It means artwork changes with the constantly changing value from the data set from human visual perception. Dan Graham showed another feedback related work, which delays 5second playback in mirror that implies consequence of time. Today's media art has to sublimate coincidence, time ant audience into philosophical artwork through consonance that comes with video and sound as we can see from Bill Viola. Stelarc produced artworks. That use input data that is weak signals from brain, muscles. Through a terminal display with player, body expanded meaning of media. Jeffrey Shaw's 'Legible City' provided a fabrication of the reality with the interaction of bicycle's pedal speed and steering direction that is controlled by 4river. RE:MARK used microphone as input device as Edmond Couchot's 'Je same a la vent' and Nam Jun Paik's 'Participant TV' did. There is no communication without feedback between human being. The reality makes audience involved into artworks. That is the reason why feedback has to be natural. Through the feedback process, the originality of the idea is altered by audience. The feedback is not just part of flesh of artwork rather skeleton of it. Technological showoff cannot be art itself The perfection of technological application plan helps feedback that interacts with audience naturally in order that audience hoes not feel the feedback as artificial plan. Interactive media art has to be evolved into new media form with new integration feedback technology.

• Journal of the Korean Geotechnical Society
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• v.28 no.11
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• pp.69-78
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• 2012

Conventional numerical analysis for rainfall-induced slope stability has been estimated by separating seepage and stress-strain behavior, respectively. Many researchers' models from commercial softwares and literatures define that partially saturated permeability is the only function of degree of saturation (or matrix suction) and then they do not consider hydraulic-mechanical characteristics for the analysis. However, in practice, the water flow processes in a deformable soil are influenced by soil skeleton movement and the pore water pressure changed due to seepage will lead to changes in stress and to deformation of a soil. The relationship between seepage and soil behavior causes a change of partially saturated permeability as well as saturated permeability with the lapse of time. Instability of partially saturated soil slopes due to infiltration would be analyzed from reduction of negative pore water pressure calculating the process of water flow based on predicted partially saturated permeability. Therefore, partially saturated permeability should be defined by the function of degree of saturation (or matric suction) and porosity. The paper presents the comparison between staggered and monolithic coupled analysis regarding seepage and stress deformation problems. As a result, the decrease in matric suction on soil slope from monolithic analysis is slower than that from staggered analysis.

• Journal of Oral Medicine and Pain
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• v.34 no.3
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• pp.295-301
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• 2009

Recently, bisphosphonate-associated osteonecrosis of the jaw(BONJ) is added to the list of diseases of the oromaxillofacial region. BONJ is defined as exposed bone in the jaw that does not heal within 8 weeks after identification, in a patient who has been received to bisphosphonates and has not taken radiation therapy to the craniofacial region. Bisphosphonates binded to bone mineral are concentrated in highly active remodeling site, reside in the skeleton for a long time, and do a role as powerful inhibitors of bone resorption. As the patients receiving bisphosphonates therapy grow in number, the patients of BONJ would go on increasing in Korea. We would like to present two patients who were suspected to BONJ, describe the outline of BONJ, and mention importance of our understanding about BONJ. BONJ is rare disease, but once it develops, its prognosis is very poor. Our adequate understanding of BONJ is necessary to prevent it and cope with it properly.

• Imaging Science in Dentistry
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• v.50 no.3
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• pp.237-243
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• 2020

Purpose: The aim of this study was to evaluate the clinical efficacy of a Tanner-Whitehouse 3 (TW3)-based fully automated bone age assessment system on hand-wrist radiographs of Korean children and adolescents. Materials and Methods: Hand-wrist radiographs of 80 subjects (40 boys and 40 girls, 7-15 years of age) were collected. The clinical efficacy was evaluated by comparing the bone ages that were determined using the system with those from the reference standard produced by 2 oral and maxillofacial radiologists. Comparisons were conducted using the paired t-test and simple regression analysis. Results: The bone ages estimated with this bone age assessment system were not significantly different from those obtained with the reference standard (P>0.05) and satisfied the equivalence criterion of 0.6 years within the 95% confidence interval (-0.07 to 0.22), demonstrating excellent performance of the system. Similarly, in the comparisons of gender subgroups, no significant difference in bone age between the values produced by the system and the reference standard was observed (P>0.05 for both boys and girls). The determination coefficients obtained via regression analysis were 0.962, 0.945, and 0.952 for boys, girls, and overall, respectively (P=0.000); hence, the radiologist-determined bone ages and the system-determined bone ages were strongly correlated. Conclusion: This TW3-based system can be effectively used for bone age assessment based on hand-wrist radiographs of Korean children and adolescents.

• Journal of Periodontal and Implant Science
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• v.41 no.4
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• pp.176-184
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• 2011

Purpose: The final goal of regenerative periodontal therapy is to restore the structure and function of the periodontium destroyed or lost due to periodontitis. However, the role of periosteum in periodontal regeneration was relatively neglected while bone repair in the skeleton occurs as a result of a significant contribution from the periosteum. The aim of this study is to understand the histological characteristics of periosteum and compare the native periosteum with the repaired periosteum after elevating flap or after surgical intervention with flap elevation. Methods: Buccal and lingual mucoperiosteal flaps were reflected to surgically create critical-size, "box-type" (4 mm width, 5 mm depth), one-wall, intrabony defects at the distal aspect of the 2nd and the mesial aspect of the 4th mandibular premolars in the right and left jaw quadrants. Animals were sacrificed after 24 weeks. Results: The results from this study are as follows: 1) thickness of periosteum showed difference as follows (P<0.05): control group ($0.45{\pm}0.22$ mm)> flap-elevation group ($0.36{\pm}0.07$ mm)> defect formation group ($0.26{\pm}0.03$ mm), 2) thickness of gingival tissue showed difference as follows (P<0.05): defect formation group ($3.15{\pm}0.40$ mm)> flap-elevation group ($2.02{\pm}0.25$ mm) > control group ($1.88{\pm}0.27$ mm), 3) higher cellular activity was observed in defect formation group and flap-elevation groups than control group, 4) the number of blood vessles was higher in defect formation group than control group. Conclusions: In conclusion, prolonged operation with increased surgical trauma seems to decrease the thickness of repaired periosteum and increase the thickness of gingiva. More blood vessles and high cellular activity were observed in defect formation group.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.4
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• pp.620-627
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• 2005

The purposes of early orthodontic intervention are to correct obvious problems, to intercept developing problems and prevent them from becoming worse. Myofunctional influence on facial growth and the dentition change in muscle function and initiate morphologic variation in the normal configuration of the teeth and enhance an already existing malocclusion. Myofunctional therapy has been advocated since 1960's as the treatment for tongue thrust and other oral habits. Pre-orthodontic $TRAINER^{(R)}$ is introduced as functional device usable in children of mixed dentition to correct functional problems concerning soft tissue, tooth and skeleton. The most common cases to treat with Pre-orthodontic $TRAINER^{(R)}$ are lower anterior crowding, anterior open bite, Class II malocclusion and deep bite. Also, it can be used as correction of oral habits. Patients in this cases visited Department of Pediatric Dentistry, School of dentistry, Dankook University for orthodontic treatment. Pre-orthodontic treatment with Pre-orthodontic $TRAINER^{(R)}$ was carried out for correction of the oral habits.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.4
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• pp.703-708
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• 2005

Cleidocranial Dysplasia(CCD) is a congenital disorder of skeletal and dental anomaly with an autosomal dominant mode of inheritance. CCD Shows a generalized defect in intramembranous bones, such as the skull, clavicles, and endochondral bones, such as the long bones and the remainder of the skeleton. The specific clinical feature of CCD is an aplasia & hypoplasia of one or both clavicles, frontal & parietal bone bossing, incomplete fontanels and sutures closure of cranial bone. Generally, relative mandibular prognathism is seen, because maxillar is underdeveloped. Dental anomalies of CCD are prolonged primary teeth, delayed eruption of the permanent teeth and multiple supernumerary teeth. Almost patients of CCD can not recognize their dental abnormality until the permanent teeth eruption was begining. So it is difficult to decide the proper timing of the treatment of patients of CCD. Pedodontists should understand the development of the dentition in CCD patient and start the treatment of CCD patient in proper time.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.3
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• pp.374-380
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• 2010

Treacher Collins syndrome(TCS) is a rare, incurable condition occurring in approximately 1 of 25,000 to 50,000 births. It may occur as a spontaneous mutation out of genetically normal parents or it may be manifested as an autosomal dominant pattern. TCS is characterized by facial deformities such as, underdevelopment of the maxilla, mandible and zygoma, malocclusion, bilateral deformities of auricles, antimongoloid slant of the palpebral fissures. The syndrome is often associated with cleft lip and palate, ear malformations and hearing loss, short stature, and anomalies of the heart and skeleton. Respiratory difficulty associated with air way obstruction may also be observed, and there is considerable difficulty in airway management during general anesthesia. It is necessary that dentists provide safe dental treatments and guidelines to TCS patients by providing adequate understanding about the characteristics of the syndrome and proper ways of managements. The purpose of this study is to report the dental and medical characteristics of the patient who visited the Department of Pediatric Dentistry, Yonsei University for multiple dental caries treatment and to review the literatures of TCS.

• Clean Technology
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• v.23 no.2
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• pp.196-204
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• 2017

CdZnS/ZnO composite was prepared through low-temperature precipitation and drying method. The property of CdZnS/ZnO as a recyclable photocatalyst for the degradation of rhodamine B (RhB) under visible light irradiation was examined. The sample was characterized by XRD, FE-SEM, XPS, UV-vis DRS and photoluminescence techniques before and after repeated reaction to investigate the change of properties during the photocatalytic reaction. During repeated reaction, the CdZnS/ZnO showed an improved photocatalytic activity and recycle stability. Among two feasible reaction pathways for photocatalytic degradation of RhB, the cleavage of conjugated chromophore was found to predominate over N-dealkylation of chromophore skeleton in the present work. The results indicate that the CdZnS/ZnO, prepared by a simple precipitation method, can be used as a visible-light driven photocatalyst with enhanced cycle stability and activity.