• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.2
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• pp.238-246
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• 1996

High-density SiC-AIN solid solutions were fabricated from powder mixtures of $\beta$-SiC and AIN by hot-pressing in the 1870 to $2030^{\circ}C$ temperature range. The reaction of AIN and $\beta$-SiC (3C) powder transformed to the 2 H (wurzite) structure appeared to depend on the temperature and SiC/A1N ratio and seeds present. The crystalline phases consisted of a SiC-rich solid-solution phase and an A1N-rich solid-solution phase. At $2030^{\circ}C$ for 1 h, for a composition of 50 % AIN/50 % SiC with a seeding of $\alpha$-SiC, the complete solid solution could be obtained and the microstructures are equiaxed with a relatively homogeneous grain size of 2 H phases. The variation of the seeding of $\alpha$-SiC in SIC-A1N solid solutions could be attributed to the transformation behaviour and differences in size and shape of the grains, as well as to other factors, such as grain size distributions, compositional inhomogeneity, and structural defects.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.164-173
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• 2014

In underwater robotics, vision would be a key element for recognition in underwater environments. However, due to turbidity an underwater optical camera is rarely available. An underwater imaging sonar, as an alternative, delivers low quality sonar images which are not stable and accurate enough to find out natural objects by image processing. For this, artificial landmarks based on the characteristics of ultrasonic waves and their recognition method by a shape matrix transformation were proposed and were proven in Part 1. But, this is not working properly in undulating and dynamically noisy sea-bottom. To solve this, we propose a framework providing a selection phase of likelihood candidates, a selection phase for final candidates, recognition phase and tracking phase in sequence images, where a particle filter based selection mechanism to eliminate fake candidates and a mean shift based tracking algorithm are also proposed. All 4 steps are running in parallel and real-time processing. The proposed framework is flexible to add and to modify internal algorithms. A pool test and sea trial are carried out to prove the performance, and detail analysis of experimental results are done. Information is obtained from tracking phase such as relative distance, bearing will be expected to be used for control and navigation of underwater robots.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.6
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• pp.1299-1308
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• 1994

This paper is considered on the dynamic behavior and the dynamic impact coefficient on the cable-stayed bridge under the vehicle load. The method of static analysis, that is, the transfer matrix method is used to get influence values about displacements, section forces of girder and cable forces. Gotten influence values were used as basic data to analyse dynamic behavior. This paper used the transfer matrix method because it is relatively simpler than the finite element method, and calculating speed of computer is very fast and the precision of computation is high. In the process of dynamic analysis, the uncoupled equation of motion is derived from simultaneous equation of the motion of cable-stayed bridge and vehicle travelling by using mode shape, which was borne from system of undamped free vibration. The solution of the uncoupled equation of motion, that is, time history of response of deflections, velocity and acceleration on reference coordinate system, is found by Newmark-${\beta}$ method, a kind of direct integral method. After the time history of dynamic response was gotten, and it was transfered to the time history of dynamic response of cable-stayed bridge by linear transformation of coordinates. As a result of this numerical analysis, effect of dynamic behavior for cable-stayed bridge under the vehicle load has varied depending on parameter of design, that is, the ratio of span, the ratio of main span length, tower height, the flexural rigidity of longitudinal girder, the flexural rigidity of tower, and the cable stiffness, investigated. Very good agreements with the existing solution in the literature are shown for the uncracked plate as well as the cracked plate.

• Journal of Plant Biotechnology
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• v.35 no.1
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• pp.55-61
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• 2008

Previous studies on genetic transformation of chrysanthemum using cold regulated gene (BN115) have been conducted and the PCR and Real-Time PCR based method to determine the presence of the transferred cold regulated gene in the chrysanthemum was established. To check whether over-expression of BN115 gene in transgenic chrysanthemum will enhance their tolerance to cold stress, the transgenic chrysanthemum were grown under low temperature condition and several cold signalling including growth characteristics, stoma size and shape, SPAD value and ion leakage test were investigated. The transgenic chrysanthemum in the low temperature growth chamber grow much faster in term of the height, number and size of the leaves than those of wild-type plants and damage of transgenic plant caused by the low temperature was much less than that of wild-type plants. The stoma type and size of transgenic plant leaves grown at $5^{\circ}C$ were much similar to of wild-type plant cultured on $25^{\circ}C$ It has been found that SPAD value of transgenic plants was much higher than those of wild-type, but the EC density being lower under low temperature condition.

• Geophysics and Geophysical Exploration
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• v.5 no.3
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• pp.206-216
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• 2002

The finite element method (FEM), a powerful numerical modeling tool for solving various engineering problems, is frequently applied to three-dimensional (3-D) modeling thanks to its capability of discretizing and simulating the shape of model with finite number of elements. Considering the accuracy of the solution and computing time in modeling of engineering problems, it is preferable to construct physical continuity and simplify mesh system. Although there exist systematic mesh generation systems for arbitrary shaped model, it is hard to model a simple cylinder in terms of 3-D coordinate system especially in the vicinity of the central axis. In this study I adopt cylindrical coordinate system for modeling the 3-D model space and define the origin of the coordinates with mathematically clear coordinate transformation. Since we can simulate the whole space with hexahedral elements, the cylindrical coordinate system is effective in handling the 3-D model structure. The 3-D do resistivity modeling scheme developed in this study provides basie principle for borehole-to-surface resistivity survey, which can be a useful tool for the application to environmental problem.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.55-58
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• 2013

Immature embryos of Glycine max L. was cultured on Murashige and Skoog's (MS) medium supplemented with 1 mg/L 2,4-dichlorophenoxy acetic acid (2,4-D). After 6 to 8 weeks of culture, immature embryos produced somatic embryos. Of somatic embryos, two cotyledonary embryo (14%), one cotyledonary embryo (37%), fused cotyledonary embryo (43%), and stunted globular embryos (6%) were observed. The procambial strand of cotyledons originated from circular procambial tissues of lower hypocotyl. The circular procambial tissues were independently divided into one or two procambial strand at the edge of cotyledonary-node, and then connected to each cotyledon to form somatic embryos with one or two cotyledons. When cotyledon was a fused type, the circular procambial strand in lower hypocotyl was continuously connected to the cotyledon. Also, somatic embryos with two cotyledons developed a functional shoot apex with the tunica-corpus structure. In contrast, somatic embryos with one or fused cotyledon formed an abnormal shoot apex without the tunica-corpus structure or with non-dome shape in the inter-cotyledonary area. These results indicated that the variation of cotyledon in somatic embryos is closely related to procambial differentiation and shoot apical meristem development.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.3
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• pp.75-83
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• 1984

The probability of failure is used to analyze the reliability of three dimensional slope failure, instead of conventional factor of safety. The strength parameters are assumed to be normal variated and beta variated. These are interval estimated under the specified confidence level and maximum likelihood estimation. The pseudonormal and beta random variables are generated using the uniform probability transformation method according to central limit theorem and rejection method. By means of a Monte-Carlo Simulation, the probability of failure is defined as; $P_f=M/N$ N: Total number of trials M: Total number of failures Some of the conclusions derived. from the case study include; 1. Three dimensional factors of safety are generally much higher than 2-D factors of safety. However situations appear to exist where the 3-D factor of safety can be lower than the 2-D factor of safety. 2. The $F_3/F_2$ ratio appears to be quite sensitive to c and ${\phi}$ and to the shape of the 3-D shear surface and the slope but not to be to the unit weight of soil. 3. From the two models (normal, beta) considered for the distribution of the factor of safety, the beta distribution generally provides lager than normal distribution. 4. Results obtained using the beta and normal models are presented in a nomgraph relating slope height and slop angle to probability of failure.

• Journal of the Korean Regional Science Association
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• v.15 no.2
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• pp.155-187
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• 1999

The East Asian Region has experienced remarkable economic growth and transformation of interurban networking over the past three decades, and urban competiti veness for a networking hub in this region has become a critical issue confronting cities. Competitiveness of the Seoul capital region for a networking hub in Northeast Asia is outstripped by other competing cities in East Asia, notwithstanding its geo-politically and geo-economically advantageous location in this region. In this paper, we aim to appraise the Seoul capital region's competitiveness in terms of logistics distribution, financial function and logistics distribution, financial function and agglomeration of transnational corporations (especially of RHOs and other managerial functions), and to advance the networking strategies of the region for a Northeast Asia hyb. As a result of analysis, we suggest that the Seoul capital region be developed as a Northeast Asian center for regional headquarters or leading global corporations and financial services for being a strategic nodal point in Northeast Asia in the 21st century. A recent survey shows that where to locate an RHQ is influenced by various factors, such as potential market and manufacturing site in the city's hinterland, quality of life, such things as culture, health, safety, education, a well-educated, English-speaking population, reliable air transport, state-of-the-art communications, and an active policy to offer foreign companies generous incentives. The Seoul capital region, which is located at a strategic nodal point advantageous as a springboard for its Northeast Asian hinterland, cannot meet the other conditions mentioned above. To overcome these drawbacks in attracting transnational capital and to create competitiveness as a strategic hub of RHQs in Northeast Asia, it is urgent to initiate a structural reform of the Korean economy, politics, and overall society, to minimize the regulation of FDI, and to provide various incentives for foreign investment. Moreover, we propose the construction of an 'International Business Town' in the Seoul capital region, as a medium to intermediate these strategies and to shape them in a spatial scale. The projected 'International Business Town(IBT)' will be a 'free city' open to international business in which liberal economic activities are guaranteed by special legislation and administration, infrastructures needed for international and improved accessibility to the airport are furnished, and the preference of foreign high-income investors for cultural and living environment are satisfactorily met. IBT is conspicuously differentiated from a raft of other cities' incentives in that it combines deregulation and incentive programs to attract the investment of transnational capital, with a spatial program of offering an urban environment preferred by the high-income investors for cultural and living environment are satisfactorily met. IBT is conspicuously differentiated from a raft of other cities' incentives in that it combines deregulation and incentive programs to attract the investment of transnational capita, with a spatial program of offering an urban environment preferred by the high-income and managerial class. Furthermore, it can be an excellent way of overcoming the xenophobia that has spread among the Korean population by concentrating foreign businesses and their lifestyles in a specific foreign businesses and their lifestyles in a specific zone. In conclusion, 'International Business Town', in line with other legislative and administrative incentive programs, will function as a driving force to make the Seoul capital regional more competitive as a regional business hub in Northeast Asia.

• Journal of Korea Society of Industrial Information Systems
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• v.24 no.6
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• pp.25-34
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• 2019

VTON (Virtual try-on) is a key technology that can activate the online commerce of fashion items. However, the early 3D graphics-based methods require the 3D information of the clothing or the human body, which is difficult to secure realistically. In order to overcome this problem, Image-based deep-learning algorithms such as VITON (Virtual image try-on) and CP-VTON (Characteristic preserving-virtual try-on) has been published, but only a sampled results on performance is presented. In order to examine the strength and weakness for their commercialization, the performance analysis is needed according to the complexity of the clothes, the object posture and body shape, and the degree of occlusion of the clothes. In this paper, IoU and SSIM were evaluated for the performance of transformation and synthesis stages, together with non-DL SCM based method. As a result, CP-VTON shows the best performance, but its performance varies significantly according to posture and complexity of clothes. The reasons for this were attributed to the limitations of secondary geometric deformation and the limitations of the synthesis technology through GAN.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.3
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• pp.70-78
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• 2000

In this study, a new method for canceling MRI artifacts through the motion translation of image plane is presented Breathing often makes problems in a clinical diagnosis. Assuming that the head moves up and down due to breathing, rigid translational motions in only y(phase encoding axis) direction are treated Unlike the conventional Iterative phase retrieval algorithm, this method is based on the MRI imaging process and analyzing of Image property A new constraint condition with which the motion component and the true image component in the MRI signal can be separated by a simple algebraic operation is extracted After the x(read out) directional Fourier transformation of MRI signal is done, the y(phase encoding) directional spectrum phasing value is Just an algebraic sum of the Image component and the motion component Meanwhile, as It is known that the density of subcutaneous fat area is almost uniform in the head tomographs, the density distribution along a y directional line on this fat area is regarded as symmetric shape If the density function is symmetric, then the phase of spectrum changes linearly with the position Hence, the departure component from the linear function can be separated as the motion component Based on this constrant condition, the new method of artifact cancellation is presented Finally, the effectiveness of this algorithm IS shown by using a phantom with simulated motions.