• The korean journal of orthodontics
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• v.35 no.3 s.110
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• pp.238-249
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• 2005

The contemporary two-jaw surgical approach usually involves a Le Fort osteotomy of the maxilla and a ramal osteotomy of the mandible with 3-dimensional repositioning of the jaws as well as the occlusal planes. After making the surgical treatment plan. the surgical movements are duplicated in the model surgery. During this procedure, reference poings and lines are drawn on the base of the models over the dental arch and sawcuts are mads according to these marked osteotomy lines. This technique, however, has been found to be inexact. especially when the laws are moved in several dimensions simultaneously. To overcome this. different methods have been developed for an accurate repositioning of the jaws as planned. A new appliance. Surgical Jaw Relater, has been devised by th8 author for the simple 3-dimensional relocation of the upper and lower models, resulting in the easy construction of the splints such as centric relation splint, intermediate and final splint. This article describes an introduction and a clinical application of this appliance. Through the application of this system to the orthognathic cases including two-law surgery. it is proved that the row device is very clinically useful.

• Journal of Chest Surgery
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• v.26 no.9
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• pp.677-685
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• 1993

Experience with bileaflet mechanical valve replacement at the Inha Hospital in 192 patients, operated on from June 1986 until April 1993. Two hundred fourty-one prostheses [51 Duromedics, 79 St.Jude Medical, and 111 CafboMedics]were implanted during the total 195 operations. Mitral valve replacment[MVR]was done in 113 cases, aortic valve replacement[AVR]in 34, tricuspid valve replacement[TVR]in 2, and double valve replacement[DVR]in 46 cases.Of the total patients, 63.0% were women and 37.0% were men. The mean age of the patients was 40.8 years, ranged from 14 to 67years. Overall early mortality was 9.2\ulcorner%[18 out of 195]; 9.7%[11 out of 113]for MVR, 14,7% [5 out of 34]for AVR, and 4.3%[2 out of 46]for DVR. All of the operative survors were followed over a period of one to 83 months with a mean of 37 months, for total 543 patient-years. So far, eleven patients[6.7% of the long-term survivors]were lost to follov-up after a mean postoperative follow-up of 22.8 months. There were nine late deaths; three deaths due to prostetic valve endocarditis, two due to persistent heart failure, one due to cerebral hemorrhage, one due to aortic dissection after Bentall oreration, and two sudden deaths. Actuarial survival rate at 6.9 years was 94.8%, There were seventeen valve-related complications; three prosthetic valve thromboses, three thrombembolisms, three instances of prosthetic valve endocarditis, two paravalvular leakages, and six hemorrhagic complications related to anticoagulation. The actuarial rate of freedom from all valve-related complications at 6.9years was 91.3%. There were significant decreases in the heart size postoperatively that can be demonstrated by comparison of cardio-thoracic ratios on simple chest X-ray and left ventricle dimensions on echocardiography. We conclude that this midterm follow-up shows good results in terms of hemodynamics and durability although further long-term evaluations are mandatory.

• Korean Journal of Cognitive Science
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• v.21 no.1
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• pp.127-143
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• 2010

This study explores children's sex differences of emotion discrimination from facial expressions based on two dimensional model of emotion. The study group consisted of 92 children, of 40, 52, and 64 months of age, and the rate of male and female children was male children (50%) and female children (50%). Children of 92 were required to choose facial expressions related the twelve emotion terms. Facial expressions applied for experiment are used the photographs rated the degree of expression in each of the two dimensions (pleasure-displeasure dimension and arousal-sleep dimension) on a nine-point scale from 54 university students. The experimental findings appeared that the sex differences were distinctly the arousal-sleep dimension than the pleasure-displeasure dimension. In the arousal-sleep dimensionoussleepness, anger, comfort, and loneliness' emotions showed large sex differences over 1 value. Especially, while male children showed high arousal more than female children in the emotions like 'sleepiness, anger and loneliness', female children showed high arousal more than male children in 'comfort' emotion.

• Korean journal of applied entomology
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• v.23 no.4 s.61
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• pp.209-214
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• 1984

Since 1980, burley tobacco plants grown mainly in the western hat of the Korea. have shown two new types of disease symptom. Both symptoms were found to be caused by two different PVY strains : the vein banding type by a PVY strain designated as PVY-VB and necrosis on leaf veins by a PVY strain designated as PVY-VN, Identification of the PVY strains was based on host range test. aphid( Myzus Persicae) transmission test, physical properties, serology, and observation of virus particle morphology. The virus particles were measured to be about 730 nm without any difference in shape or dimensions between the two strains. Both strains also gave a positive reaction to the PVY antiserum in SDS-agar gel double diffusion test. These strains, however, gave a negative reaction to the tobacco etch virus and tobacco vein mottling virus antisera.

• Interaction and multiscale mechanics
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• v.2 no.3
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• pp.321-332
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• 2009

Recent development in composites containing phase-transforming particles, such as vanadium dioxide or barium titanate, reveals the overall stiffness and viscoelastic damping of the composites may be unbounded (Lakes et al. 2001, Jaglinski et al. 2007). Negative stiffness is induced from phase transformation predicted by the Landau phase transformation theory. Although this unbounded phenomenon is theoretically supported with the composite homogenization theory, detailed stress analyses of the composites are still lacking. In this work, we analyze the stress distribution of the Hashin-Shtrikman (HS) composite and its two-dimensional variant, namely a circular inclusion in a square plate, under the assumption that the Young's modulus of the inclusion is negative. Assumption of negative stiffness is a priori in the present analysis. For stress analysis, a closed form solution for the HS model and finite element solutions for the 2D composite are presented. A static loading condition is adopted to estimate the effective modulus of the composites by the ratio of stress to average strain on the loading edges. It is found that the interfacial stresses between the circular inclusion and matrix increase dramatically when the negative stiffness is so tuned that overall stiffness is unbounded. Furthermore, it is found that stress distributions in the inclusion are not uniform, contrary to Eshelby's theorem, which states, for two-phase, infinite composites, the inclusion's stress distribution is uniform when the shape of the inclusion has higher symmetry than an ellipse. The stability of the composites is discussed from the viewpoint of deterioration of perfect interface conditions due to excessive interfacial stresses.

• Journal of Families and Better Life
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• v.22 no.6 s.72
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• pp.155-164
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• 2004

The purpose of this study is to discover similarities and dissimilarities in life style and other factors for housing choices between two generations living in same household. It will provide knowledge that is helpful in understanding the two generations and develop marketing strategies for houses as a commodity that accommodates the life style of both generations. The data of this study were collected from October to November 2003, using a structured, self-report questionnaire that contains questions on 40 dimensions of life style and 33 items on housing choices. The original respondents consisted of 307 university students and their parents living in Seoul. The ages of the younger generation were limited from ぉ to 29. The final participants in this study included 224 sets of university students and their parents, that is, about 448 respondents. Frequency, percentage, factor analysis, paired t-test and means were used for data analysis. The results show that the life style may be divided into nine sub-types. There were generational differences in If-oriented lifestyle, Conservative lifestyle, As- service self-expression lifestyle, Pragmatic lifestyle, Convenience lifestyle, Self-development lifestyle, and Leisure-oriented lifestyle. Especially in the categories of Convenience lifestyle, If-oriented lifestyle and Positive Self-expression lifestyle, the younger generation ranked higher than their parents. The most important factors in housing choice may be divided into eight sub-categories. Among them are economic factors, housing amenities, housing design, distance from parents and children, social and environmental qualifies, and distance from work place and school. The two generations differed over the importance of the factors. The younger generation particularly valued the factors of distance from parents and children, housing amenities, housing design.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.7C
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• pp.719-725
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• 2003

The content-based image retrieval system extracts features of color, shape and texture from raw images, and builds the database with those features in the indexing process. The search in the whole retrieval system is defined as a process which finds images that have large similarity to query image using the feature database. This paper proposes a new two-stage search method in the content-based image retrieval system. The method is that the features are condensed and stored by the property of Cauchy-Schwartz inequality in order to reduce the similarity computation time which takes a mostly response time from entering a query to getting retrieval results. By the extensive computer simulations, we have observed that the proposed two-stage search method successfully reduces the similarity computation time while maintaining the same retrieval relevance as the conventional exhaustive search method. We also have observed that the method is more effective as the number of images and dimensions of the feature space increase.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.30 no.3
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• pp.123-129
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• 2018

In this study, CFD is used to compare and analyze the flow characteristics using reflected pressure wave during the intersection of two trains in straight tunnel. Two tunnels of different lengths; 600 m and 3,400 m were designed and numerical analysis of the flow characteristics of two tunnels carried out by setting the crossing state of the two trains at a constant velocity of 27 m/s form the center of the tunnel. The simulation model was designed using the actual tunnel and subway dimensions The train motion was achieved by using the moving mesh method. For the numerical analysis, $k-{\omega}$ standard turbulence model and an ideal gas were used to set the flow conditions of three-dimensional, compressible and unsteady state. In the analysis results, it was observed that the inside of the long tunnel without interference of the reflected pressure wave was maintained at a pressure lower than the atmospheric pressure and that the flow direction was determined by the pressure gradient and shear flow. On the other hand, the flow velocity in the short tunnel was faster and the pressure fluctuation was noted to have increased due to the reflected pressure wave, with more vortices formed. In addition, the flow velocity was noted to have changed more irregularly.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.2
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• pp.223-234
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• 2014

This paper proposes a flexible and highly reusable modeling methodology for a next-generation combat entity which enables joint analysis of performance/engagement effectiveness. According to the scope of the proposed work, the paper is divided into two parts; Part 1 focuses on a conceptual model design, whereas Part 2 proposes detailed model specification and implementation. In Part 1, we, first, classify the combat entity model as combat logic and battlefield function sub-models for joint analysis. Based on the sub-models, we propose two dimensional model partition method, which creates six groups of a single combat entity model by two dimensions: three-activity and two-abstraction. This grouping enables us to reconfigure the combat entity model by sharing the same interface within the group, and the same interface becomes the fundamental basis of the flexible model composition. Furthermore, the proposed method provides a model structure that effectively reflects the real world and maximizes the multi-level reusability of a combat entity model. As a case study, we construct a model design for anti-surface ship warfare. The case study proves enhancement of model reusability in the process of scenario expansion from pattern running to wire guided torpedo operations.

• Advances in concrete construction
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• v.5 no.5
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• pp.451-468
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• 2017

The problem of reducing the self-weight of reinforced concrete structures is very important issue. There are two approaches which may be used to reduced member weight. The first is tackled through reducing the cross sectional area by using voids and the second through using light weight materials. Reducing the weight of slabs is very important as it constitutes the effective portion of dead loads in the structural building. Eleven slab specimens was casted in this research. The slabs are made one way though using two simple supports. The tested specimens comprised three reference solid slabs and eight styropor block slabs having (23% and 29%) reduction in weight. The voids in slabs were made using styropor at the ineffective concrete zones in resisting the tensile stresses. All slab specimens have the dimensions ($1100{\times}600{\times}120mm$) except one solid specimens has depth 85 mm (to give reduction in weight of 29% which is equal to the styropor block slab reduction). Two loading positions or cases (A and B) (as two-line monotonic loads) with shear span to effective depth ratio of (a/d=3, 2) respectively, were used to trace the structural behavior of styropor block slab. The best results are obtained for styropor block slab strengthened by minimum shear reinforcement with weight reduction of (29%). The increase in the strength capacity was (8.6% and 5.7%) compared to the solid slabs under loading cases A and B respectively. Despite the appearance of cracks in styropor block slab with loads lesser than those in the solid slab, the development and width of cracks in styropor block slab is significantly restricted as a result of presence a mesh of reinforcement in upper concrete portion.