• Journal of the Korean Magnetics Society
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• v.19 no.5
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• pp.157-160
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• 2009

We have studied electronic structures and magnetic properties of one dimensional Ge chain nanoclusters using OpenMX method based on densty functional method. The calculation results show the strong antiferromagnetic interaction between Cr and Ge atoms. The magnetic interaction between Ge and Ge atoms are almost antiferromagnetic behaviors. The magnetic exchange interaction are occurred over the sevaral Ge atom layers. The magnitude of this interaction depends number of Ge atom.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.12 no.3
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• pp.57-62
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• 1990

Many alloplastic materials have been used as the bony substitute in large bony defects caused by fracture, periodontitis, & cyst, etc. Nowadays Hydroxyapatite(HAP) is the most usable material as the bony substitute. The reasonable properties of HAP are nontoxic, biocompatible to host tissues & have osteoconductivity. Other bioceramic materials are recommended as the bony substitute with high success rate. We have studied the clinical use of HAP as the bony substitute in the defected area caused by cyst. The reasonalbe & successful results are obtained. The results were as followed. 1. Better prognosis was obtained in the case of HAP & bone mixed graft than HAP graft only. And the best prognosis was obtained in the case of iliac bone graft. 2. Better prognosis was obtained in Mx. than in Mn. 3. It seems that the soft tissue ingrowth into the HAP granule play an important role in the success of the HAP graft. 4. Though the flap covering the HAP granules was perforated, the relative good prognosis was obtained by re-suturing the perforeated site.

• Geomechanics and Engineering
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• v.16 no.1
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• pp.71-83
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• 2018

Compacted bentonites were chosen as the backfill material and buffer in high level nuclear waste disposal due to its high swelling pressure, high ion adsorption capacity and low permeability. It is essential to estimate the swelling pressure in design and considering the safety of the nuclear repositories. The swelling pressure model of expansive clay colloids was developed based on Gouy-Chapman diffuse double layer theory. However, the diffuse double layer model is effective in predicting low compaction dry density (low swelling pressure) for certain bentonites, and invalidation in simulating high compaction dry density (high swelling pressure). In this paper, the new relationship between nondimensional midplane potential function, u, and nondimensional distance function, Kd, were established based on the Gouy-Chapman theory by considering the variation of void ratio. The new developed model was constructed based on the published literature data of compacted Na-bentonite (MX80) and Ca-bentonite (FoCa) for sodium and calcium bentonite respectively. The proposed models were applied to re-compute swelling pressure of other compacted Na-bentonites (Kunigel-V1, Voclay, Neokunibond and GMZ) and Ca-bentonites (FEBEX, Bavaria bentonite, Bentonite S-2, Montigel bentonite) based on the reported experimental data. Results show that the predicted swelling pressure has a good agreement with the experimental swelling pressure in all cases.

• Journal of Korean Academy of Nursing
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• v.34 no.3
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• pp.485-494
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• 2004

Purpose: This study was aimed to develop a WBI(Web Based Instruction) program on safety for 3rd grade elementary school students and to test the effects of it. Method: The WBI program was developed using Macromedia flash MX, Adobe Illustrator 10.0 and Adobe Photoshop 7.0. The web site was http://www.safeschool.co.kr. The effect of it was tested from Mar 24, to Apr 30, 2003. The subjects were 144 students enrolled in the 3rd grade of an elementary school in Gyungju. The experimental group received the WBI program lessons while each control group received textbook-based lessons with visual presenters and maps, 3 times. Data was analyzed with descriptive statistics, and ${\chi}^2$test, t-test, and repeated measure ANOVA. Result: First, the WBI group reported a longer effect on knowledge and practice of accident prevention than the textbook-based lessons, indicating that the WBI is more effective. Second, the WBI group was better motivated to learn the accident prevention lessons, showing that the WBI is effective. As a result, the WBI group had total longer effects on knowledge, practice and motivation of accident prevention than the textbook-based instruction. Conclusion: We recommend that this WBI program be used in each class to provide more effective safety instruction in elementary schools.

• Magazine of the Korea Concrete Institute
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• v.5 no.1
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• pp.115-127
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• 1993

본 연구의 목적은 프리캐스트 콘크리트(P.C) 대형판 아파트 구조물에 대한 우리나라 내진설계기준안 및 지침을 수립하기 위해 필요로 하는 정보를 취득하는데 있다. 이것은 실제 지진과 유사한 진동을 발생시키는 진동대를 사용하여 P.C대형판 구조물의 거동을 분석관찰함으로써 달성되었다. 여기에 사용된 시험체중의 하나는 습식접합 1/3 축소 3층 입체 P.C모델이었다. 지진파를 일으키기 위해 4mx4m 크기의 진동대가 사용되었다. 또한 선택한 입력지진가속도파는 Taft N21E 성분기록지진파로서 최대지진가속도(PGA)는 원하는 지진세기수준에 따라 조정되었고 시간축으로는 동적상사성법칙에 따라 축소되었다. 이 P.C모델의 진동대 실험을 통해 얻은 결과를 근거로 하여, 근거로 하여 다음과 같은 결론을 도출하였다. (1)이 시험체에 관한한, 지진안전계수는 7-8정도로 나타났으며, (2)이 P.C모델이 감쇠계수는 대체로, 철근콘크리트구조물 감쇠계수의 두배에 해당하는 값인 8%정도이며, (3) 이 모델은 접합부의 벌어짐과 미끄러짐에 의한 에너지소산을 통해서 2-3정도의 전체적인 변위연성비를 보여주었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.6
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• pp.525-528
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• 2011

A deep circumflex iliac artery (DCIA) flap is usually used for reconstruction in oral and maxillo-facial surgery department since introduced by O'Brien in 1975. Various flap designs are possible for osteomusculocutaneous, musculocutaneous, musculosseous and vascularized bone types. Iliac crest shape is similar to contour of mandible. Moreover, though a fibular flap has only 15~20 mm of cutting plane width, a DCIA flap contains much more bone amount, making this a similar reconstruction compare with normal mandible. A 68 year-old male with squamous cell carcinoma on the anterior floor of the mouth had an impression with T2N0Mx and the treatment procedure was DCIA reconstruction after wide resection and marginal mandibulectomy, with both supraomohyoid neck dissection. We present an experience of DCIA flap for reconstruction with a literature review.

• Journal of IKEEE
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• v.23 no.4
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• pp.1387-1392
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• 2019

Aspherical mirrors have lighter weight and better performance than spherical mirrors, but it is difficult to process their shape and measure the processing precision. Especially, large aperture aspherical mirrors mounted on satellites need high processing precision and long processing time. The computerized numerically controlled machine of gantry type has been used in polishing process, but it has difficulties in processing the complex shapes due to the lack of degrees of freedom. In order to overcome this problem we developed a polishing system using an articulated industrial robot. The system consists of tool path generating program, real-time robot monitoring, and control program. We show the performance of the developed system through the computer simulation and actual robot operation.

• Journal of the Korean Society of Fashion and Beauty
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• v.3 no.3 s.3
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• pp.41-47
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• 2005

This study was conducted with 60 adult males who visited the Atomi Cooperative Clinic(Atomi Dermatology/Pediatrics/Oriental Clinic) in Seoul between May 2003 and December 2004; they were divided into three groups, each of which consisted of 20 persons, according to the level of erythma and then each group was subdivided to consist of ten according to whether they received skin treatment and care. The standard care provided to two groups involved topical steroids and oriental medicines prescribed by a dermatologist and a oriental doctor, respectively. 5th-grade topical steroid ointment was applied to the face and 3rd-grade to the limbs; a oriental medicine was administered in a lukewarm state half an hour after meals three times a day. To determine how special and systematic skin treatment and care was helpful in treating atopy, a skin treatment system was applied to the experimental group while the control group was provided with standard care alone. By using Mexameter(MX18) manufactured by ck-mpa as a measuring tool, the inflammation level was observed at the right antecubital space during each visit to the clinic. In view of the re suits, introduction of the systemic skin care for A. D to legitimate treatment provided by a medical institution is expected to be an appropriate supplementary treatment for adult patients who suffer from frequent recurrence of atopic dermatitis.

• Journal of Sensor Science and Technology
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• v.16 no.3
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• pp.211-219
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• 2007

This paper describes the development of 6-axis force/moment sensor for a humanoid robot. In order to walk on uneven terrain safely, the robot's foot should perceive the applied forces Fx, Fy, Fz and moments Mx, My, Mz to itself, and be controlled by the foot using the forces and moments. Also, in order to grasp unknown object safely, the robot's hand should perceive the weight of the object using the mounted 6-axis force/moment sensor to its wrist, and be controlled by the hand using the forces and moments. Therefore, 6-axis force/moment sensor should be necessary for a humanoid robot's hand and foot. In this paper, 6-axis force/moment sensor for a humanoid robot was developed using many PPBs (parallel plate-beams). The structure of the sensor was newly modeled, and the sensing element of the sensor was designed using theoretical analysis. Then, 6-axis force/moment sensor was fabricated by attaching strain-gages on the sensing elements, and the characteristic test of the developed sensor was carried out. The rated outputs from theoretical analysis agree well with the results from the experiments.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.375-375
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• 2014

Layered semiconductor materials can be a promising candidate for large-area thin film transistors (TFTs) due to their relatively high mobility, low-power switching, mechanically flexibility, optically transparency, and amenability to a low-cost, large-area growth technique like thermal chemical vapor deposition (CVD). Unlike 2D graphene, series of transition metal dichalcogenides (TMDCs), $MX_2$ (M=Ta, Mo, W, X=S, Se, Te), have a finite bandgap (1~2 eV), which makes them highly attractive for electronics switching devices. Recently, 2D $MoS_2$ materials can be expected as next generation high-mobility thin-film transistors for OLED and LCD backplane. In this paper, we investigate in detail the electrical characteristics of 2D layered $MoS_2$ local bottom-gated transistor with the same device structure of the conventional thin film transistor, and expect the feasibility of display application.