• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.4
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• pp.461-469
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• 2008

This paper proposes a hybrid symbol offset estimation algorithm for MIMO(Multiple Input Multiple Output) OFDM system. As MIMO OFDM systems are multiple transmitter and receiver antenna systems, apart from SISO(Single Input Single Output) system, it is possible to use several combining techniques which are used in multiple receive antenna system. In this paper, we propose hybrid symbol offset estimation algorithms using combining techniques in multiple receive antenna systems, simulate and show the performances in MIMO system environments. The proposed equal gain combining correlation algorithm has better performance 1.8 times in searching the ideal symbol offset rather than the conventional early symbol offset algorithm in severe ISI channel.

• Korean Journal of Computational Design and Engineering
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• v.11 no.2
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• pp.77-87
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• 2006

It is necessary to change the existing design process to cope with a short life-cycle product and various customer's demands. Also a frequent design change may delay the whole design process and it will increase the unit cost of the production. New alternatives or techniques have emerged to solve the existing design problems, such as a knowledge based engineering, an intelligent CAD, a function based design, and so on. In this paper, we propose a hybrid design system with a knowledge based design methodology and a function based design technique. The knowledge based design is good at a frequent design change and the function based design is effective to extract a core design behavior. In an early design process, the system utilizes a core design behavior through the function based design process. On the other hand, the system manages complicated design issues with the knowledge based design technique in the detailed design process. We conclude that the hybrid design system can bring fair effects on implementing an efficient design environment in aspect of time and expense.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1102-1106
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• 2015

A hybrid supercapacitor (HS) is an energy storage device used to enhance the low weight energy density (Wh/kg) of a supercapacitor. On the other hand, a sudden decrease in capacity has been pointed out as a reliability problem after many charge/discharge cycles. The reliability problem of a HS affects the early aging process. In this study, the capacity performance of a HS was observed after charge/discharge. For detailed analysis of the initial charge/discharge cycles, the charge and discharge curve was measured at a low current density. In addition, a solid electrolyte interphase (SEI) layer was confirmed after the charge/discharge. A HC composed of a lithium titanate (LTO) anode and active carbon cathode was used. The charge/discharge efficiency of the first cycle was lower than the late cycles and the charge/discharge rate was also lower. This behavior was induced by SEI layer formation, which consumed Li ions in the LTO lattice. The formation of a SEI layer after the charge/discharge cycles was confirmed using a range of analysis techniques.

• Journal of the Korean housing association
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• v.26 no.3
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• pp.11-24
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• 2015

There have not been many debates on the subject of Korean architecture during the transformative period of Gae Wha Gi (開化期: Enlightenment Period of Korea), when Western-style buildings first appeared in Seoul. This study begins by finding and recording those buildings in Seoul that show the gradual adoption and appropriation of Western architectural elements at the turn of the 20th century. By exploring the confluence of two different architectural styles, this paper attempts to look carefully at the hybrid conditions that resulted from encounters between the Koreans and the Westerners in the late 19th and early 20th century. Beginning with discovering the first products of the Western architectural influence in Seoul, this study explores the uneasy co-existence between the traditional Korean architectural style, and the Western architectural style. This co-existence ultimately bred new building techniques, and interior layouts; the appearance of these hybrid buildings illustrate the gradual transition from the traditional way, in which users modified, combined and appropriated various elements from both styles. Analyzing historical documents and photos, this study tries to capture a detailed image of the period when the influence of the Western architecture had an unavoidable impact and brought change to the traditional architecture of Korea.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.1
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• pp.41-48
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• 1995

Tobacco mosaic virus (TMV), TMV-common strain, causes severe damage on flue-cured tobacco in Korea. As the results, breeding programs were conducted to transfer the TMV resistance from NC567 to other cultivars. Advantage of F1, hybrid may not lie only in their heterotic value but also in directly combining of valuable dominant traits, e.g. for disease resistance, either in pairs or as groups already assembled in the two parents. A new TMV resistant flue-cured tobacco variety KF114 was developed from a cross as maternal parent MSNC567 and NC82 at the Suwon Experiment Station. KF114 was more vigorous growth characteristics in early stage than that of NC82, standard variety in Korea, and other characters were similar to those of NC82. It os high resistance to TMV, but bacterial wilt(Pseudomonas solanacerum) and black shank (Phytophthora parasitica var. nicotianae) is comparable to NC82. It should adapt well to the flue-cured production area and can reduce premature flowering under unfavorable weather conditions. Yield of KF114 is 1% to 5% higher, and nearly equal in value per KG compared with NC82. This variety, F1 hybrid, met acceptable standards for chemical and physical characteristics of cured leaf and high ranked good smoking taste by panel members in Korea Ginseng and Tobacco Research Institute.

• Archives of Plastic Surgery
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• v.48 no.4
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• pp.427-432
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• 2021

The conventional approach of looking down a microscope to perform microsurgical procedures is associated with occupational injuries, anti-ergonomic postures, and increased tremor and fatigue, all of which predispose microsurgeons to early retirement. Recently, three-dimensional (3D) visualization of real-time microscope magnification has been developed as an alternative. Despite its commercial availability, no supermicrosurgical procedures have been reported using this technology to date. Lymphovenous anastomoses (LVAs) often require suturing vessels with diameters of 0.2-0.8 mm, thus representing the ultimate microsurgical challenge. After performing the first documented LVA procedure using 3D-augmented visualization in our unit and gaining experience with this technique, we conducted an anonymized in-house survey among microsurgeons who had used this approach. The participants considered that 3D visualization for supermicrosurgery was equivalent in terms of handling, optical detail, depth resolution, and safety to conventional binocular magnification. This survey revealed that team communication, resident education, and ergonomics were superior using 3D digital hybrid visualization. Postoperative muscle fatigue, tremor, and pain were also reduced. The major drawbacks of the 3D visualization microscopic systems are the associated costs, required space, and difficulty of visualizing the lymphatic contrast used.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.14 no.1
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• pp.70-74
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• 2006

Cospas-Sarsat, an international satellite system for search and rescue, started operating in early 1980's and has been credited with saving thousands of lives since then. Hundreds of thousands of aviators, mariners and land users worldwide are equipped with Cospas-Sarsat distress beacons, which could help save their lives in emergency situations anywhere in the world. This paper outlines the evolution of the system and describes how satellites are constantly circling the globe monitoring for rescue signals, while tracking stations on six continents receive the satellite signals, compute the locations of the distress events and forward the calls for help to the appropriate rescue authorities. Therefore, this paper points out the importance of developing of technologies of Hybrid Aviation Wireless SAR Equipment and also proposes to make it localized.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.3
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• pp.140-148
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• 2014

In this paper, We proposed Gaussian function as a basis of hybrid method. Hybrid method is to extrapolate late time and high frequency data using early time and low frequency data. This method takes advantages of both MOT and MOM as well as having shorter running time and smaller error. For this method a better basis function is required. We compared the performance of the result with proposed function and conventional basis including Hermite and Laguerre polynomial.

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.4
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• pp.398-408
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• 2016

Based on non-completely hybrid flow line scheduling of panel block in shipbuilding, several uncertain factors influencing the problem were analyzed in a real environment, and a nonlinear integer programming model was built for each sub-scheduling problem. To narrow the difference between theory and application, rolling horizon and rescheduling methods are proposed. Moreover, with respect to the uncertainty of processing time, arriving time and due time, we take the minimizing of the early and delayed delivery costs as the objective, and establish an evaluation with a global penalty function. Finally, numerical experiments and a simulation analysis were undertaken to demonstrate the effectiveness of the model and algorithm.

• Proceedings of the Membrane Society of Korea Conference
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• 1999.07a
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• pp.79-82
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• 1999

Using Small Angle Light Scattering (SALS), the effect of quench depth on the kinetics of phase separation for ternary solution blends was investigated. The system was composed of two polymers (polystyrene and polybutadiene) and a solvent (toluene). The analyses of the early stage of phase separation were based of the Cahn-Hilliard theory [1,5]. Apparent diffusion coefficients and the fastest mode of fluctuations were evaluated, when quench depth of the system were varied near the critical composition of polymer. In the late stage of phase separation, the domain growth showed a power law with the 1/3 exponent, i.e. $q_m(t)~t^{-1/3}$. For comparison between real images and scattering profiles with time, the image of phase domains with time were obtained by using Laser Confocal Scanning Microscopy (LSCM).