• Journal of electromagnetic engineering and science
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• v.12 no.3
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• pp.216-222
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• 2012

This paper presents a single-pole eight-throw switch, based on an eight-way power divider, using substrate integrate waveguide(SIW) technology. Eight sectorial-lines are formed by inserting radial slot-lines on the top plate of SIW power divider. Each sectorial-line can be controlled independently with high level of isolation. The switching is accomplished by altering the capacitance of the varactor on the line, which causes different input impedances to be seen at a central probe to each sectorial line. The proposed structure works as a switching circuit and an eight-way power divider depending on the bias condition. The change in resonant frequency and input impedance are estimated by adapting a tapered transmission line model. The detailed design, fabrication, and measurement are discussed.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.2
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• pp.257-271
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• 1996

Livestock products like meat, milk and egg have been principal food sources for human beings since the historic periods of time. Nowadays consumption of these food items have been avoided due to its high contents of SFA, cholesterol and total fat which are major culprits of chronic adult diseases causing major deaths of people. However, the relationship between livestock products and diseases is not always true because the amounts of fat and cholesterol and types of fatty acids in meat and meat by-products depend on the part of the meat and types of animals. Although meat intakes do not always cause mai or adult diseases, still the developmental necessity does exist for animal foods equipped with biologically active properties, which in turn can improve nutritional status and health more than ever Meat with high protein lean part and low fat can be produced by applying synthetic somatotropin and beta-adrenergic agonists like clenbuterol, cimaterol etc. during breeding. This application brings benefits like higher growth rate, lower fat contents and improve feed efficiency ratios. Meats fortified with long chain PUFA($\omega$-3 fatty acids) can also be produced by modulating feed composition.Egg Products have faced the reduced sales annually because of its high cholesterol contents. Recently brand eggs fortified with special nutrients or chemical components having functional proper ties in the human body system are very popular Research Interests have been focused on eggs with low cholesterol and high omega-3 fatty acids. Low cholesterol eggs and high omega-3 eggs can be produced in several different ways, but popular way to increase is feeding the feeds with different oil sources containing high omega-3 and 6 fatty acids such as fish oil, perilla oil, linseed oil and lecithin etc. But proper compositon of feed formula should be found and economically beneficial. Brand eggs fortified with vitamin, mineral, unknown growth factors are also manufactured. Low cholesterol and high $\omega$-3 PUFA milk are marketed recently Cholesterol removal technology is not completely established and has several limitations to be overcome. Milk fortified with $\omega$-3 fatty acids is made by incorporating high &13 fatty acid foods in feed despite of extraordinary way of fatty acid metabolism In cow. All these biologically active products will be very beneficial and useful for human consumption when limitations of manufacturing technology such as safety and lowered sensory qualities are resolved. Furthermore, thorough and precise tests and quality control for these products should be performed to ensure the effectiveness and usefulness in terms of improving health and nutritional status in general. However one caution should be pointed out to lay people informing that these items are nothing but a food and not panacea. Therefore, it is important to remember that the only way of maintaining good health is absolutely through consuming balanced diet.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.6
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• pp.1409-1418
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• 1998

The recent audio CODEC(Coding/Decoding) algorithms are complex of several coding techniques, and can be divided into DSP tasks, controller tasks and mixed tasks. The traditional DSP processor has been designed for fast processing of DSP tasks only, but not for controller and mixed tasks. This paper presents a new architecture that achieves high throughput on both controller and mixed tasks of such algorithms while maintaining high performance for DSP tasks. The proposed processor, YSP-3, operates four algorithms while maintaining high performance for DSP tasks. The proposed processor, YSP-3, operates functional units (Multiplier, two ALUs, Load/Store Unit) in parallel via 4-issue super-scalar instruction structure. The performance evaluation of YSP-3 has been done through the implementation of the several DSP algorithms and the part of the AC-3 decoding algorithms.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.4
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• pp.693-702
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• 2002

The aim of this study is to develop a 3-dimensional dynamic analysis model, capable of considering the interaction between vehicles and bridges more accurately. The dynamic analysis model is developed with the high-speed train (KTX) and a 2-span continuous prestressed concrete box girder bridge with a double track. The 20-car model is developed using the moving vehicle model for the regular trainset. Three-dimensional frame elements are used for the bridge model. Using the developed models, a dynamic behavior analysis program is coded. The analytical results are compared with the dynamic field test results and found to be valid to yield quite accurate dynamic responses. Based on the results of this study, the hybrid model, made up of the moving vehicle model for the heaviest power car and the moving force model for the other cars, is quite simple and effective without loosing the accuracy that much. Under the coincidence condition of two trains traveling with resonance velocity in the opposite directions, it is necessary to check not only the dynamic responses of the bridge with one-way traffic but those with two- way coincidence.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.392-397
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• 1993

Generally machine tools can be divided into three components : NC Controller, the electrical drives and the mechanical transmission elements. For high speed, high precision machining, high performance control of servo system must be accommodated and one must carefully define the interface among three components. In this paper, we suggest a way to assist future development of CNC controller by investigating the characteristics resulting from different interface between CNC controller and servo system.

• Applied Microscopy
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• v.50
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• pp.21.1-21.3
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• 2020

Sample preparation is significantly important to the high-resolution transmission electron microscopy (HRTEM) characterization of nanomaterials. However, many general organic solvents can dissolve the necessary organic polymer support layer in TEM grid, which causes it difficult to obtain high-quality samples of oil-soluble nanomaterials. In this study, a new sample preparation method for oil-soluble nanomaterials has been developed by using the sublimable material as a transition layer. Experiments also show that there is no damage to TEM grids and high-quality HRTEM images can be obtained via this method. This approach paves the way to applicable HRTEM sample preparation of oil-soluble nanomaterials.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.10
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• pp.3409-3422
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• 2014

The frequency spectrum available for the wireless communication is extremely crowded. In order to improve the spectral efficiency, the two-way relay networks have aroused great attention. A simple $N^{th}$ best-relay selection criterion for the opportunistic two-way relay networks is proposed, which can be implemented easily by extending the distributed timer technique in practice, since the proposed criterion is mainly based on the channel gains. The outage performance of the proposed relay selection scheme is analyzed under the outdated channel state information (CSI), and a tight closed-form lower bound and asymptotic value of the outage probability over Rayleigh fading channels are obtained. Simulation results demonstrate that the tight closed-form lower bound of the outage probability very closely matches with simulated ones in the whole SNR region, and the asymptotic results provide good tight approximations to the simulation ones, especially in the high SNR region.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.1
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• pp.70-81
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• 2017

Various components of an engine nozzle are modeled as flexible multi-body components that are operated under high temperature and pressure. In this paper, in order to predict complex behavior of an engine nozzle, thermo-fluid-flexible multi-body dynamics coupled analysis framework was developed. Temperature and pressure on the nozzle wall were obtained by the steady-state flow analysis for a two-dimensional nozzle. The pressure and temperature-dependent material properties were delivered to the flexible multi-body dynamics analysis. Then the deflection and strain distribution for a nozzle configuration was obtained. Heat conduction and thermal analyses were done using MSC.NASTRAN. The present framework was validated for a simple nozzle configuration by using a one-way coupled analysis. A two-way coupled analysis was also performed for the simple nozzle with an arbitrary joint clearance, and an asymmetric flow was observed. Finally, the total strain result for a realistic nozzle configuration was obtained using the one-way and two-way coupled analyses.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.5
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• pp.667-676
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• 1999

The roles of ceria on three-way catalyst is to improve the noble metal dispersion and thermal stability of support ${\gamma}$-$Al_2O_3$. And, ceria has a oxygen storage capacity(OSC) under fuel rich/lean conditions to improve the operating windows of NOx, THC and CO conversion. However, ceria has weak thermal stability under high temperature due to the crystallite growth. So that, the OSC of ceria is decreased, and then the conversions of NOx, THC and CO is decreased. One way of enhancing the thermal stability and NOx, THC and CO conversion Pd-only catalyst is to improve as well as its thermal stability and oxygen storage capacity of the ceria. Especially, the appropriate mixing ratios of bulk and stabilized ceria are very important for designing principles of Pd-only three-way catalysts. In this paper, we discussed the thermal properties of stabilizedand unstabilized (bulk) ceria, and the oxygen storage capacity (OSC) of catalysts, and found the correlation between activity and the OSC of Pd-only catalysts with various different mixing ratios of bulk and stabilized ceria. Finally, we propose the design principles to improve the thermal stability of washcoated Pd-only catalysts.

• Journal of Urban Science
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• v.9 no.1
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• pp.75-90
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• 2020

Günter Behnisch is one of the architects who played a major role as a pioneer of German modern architecture after World War II. After experiencing the era of the oppression of the Nazi right-wing national socialist, he tried to break away from the high-pressure and arrogant architecture to control everything in the building and to create a building that was born in a democratic way of thinking. He thought that architecture showed us the way we treat ourselves and the world, and that architecture formed our world view backwards. In this way, architects can express their way of thinking about their society through their works. Behnisch judged that the educational facility was the most appropriate use for implementing his democratic mindset. He hoped that this would give students the characteristics of democracy through architecture. Schools are a place where small society is experienced, and it is thought to be a medium for him to implement democratic thinking in school architecture. This study analyzed the educational facilities of Behnisch by deriving the analysis elements through the educational space organization reflecting Prakash Nair's educational facilities and educational theory and his architectural philosophy. The various plans, sections and spaces, which are characteristics of the his school facilities analyzed in this study, are expected to be helpful as data for presenting variety to many educational facilities in Korea.