• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.8
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• pp.597-603
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• 2008

The catalyzed diesel particulate filter (CDPF) is widely used for collecting soot from the exhaust gas of diesel engine. However, the CDPF need being regenerated after the soot accumulation. It is important to know characteristics of regeneration for CDPF with variation of exhaust gas temperature and composition. This study presents characteristics of regeneration according to variable exhaust gas composition. Furthermore, the experiment were performed variable gas temperature of CDPF inlet gas at each exhaust gas composition. Test-rig is used to control at each in let gas temperature and composition during regeneration of CDPF. Reaction intensity($I_c$) is used to compare with each result. Experimental results indicated that increased concentration of $NO_x$ and $O_2$ lead to regenerate more greatly. Also, higher temperature of exhaust gas leads to make CDPF cleaner.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.16 no.3
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• pp.325-332
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• 2009

Purpose: This study was done to investigate the relationship among the life style, body composition, and BMD in female college students. Method: For this study, 320 female college students aged 18 through 35 were sampled. Data were collected from June to September, 2007. The BMD was measured with Dual Energy X-ray Absorptiometry, body composition with the Body Composition Analyzer, and stature was also taken. Results: Our findings indicated that the relationship among the life style, body composition and BMD significantly varied and that meal times (F=3.318, p= .038) and muscle mass (r= .240, p< .001) and fat-free mass (r= .233, p< .001) showed a significant positive relationship with BMD. Conclusions: Our findings indicated that optimal levels of the fat-free mass and muscle mass should be maintained. Since a decrease in the quantity of bones is expected to cause health issues for women after menopause, it is necessary to reduce risk factors including the unhealthy life style of college women that may lead to osteoporosis, and to introduce preventive nursing interventions against osteoporosis.

• The Korean Journal of Ceramics
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• v.2 no.2
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• pp.89-94
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• 1996

Aluminum and zinc titanium silicate sol-gel films were fabricated for application of waveguide and the effect of additions of ZnO and $Al_2O_3$ to binary titanium silicate films was investigated. During firing, the films are densified as they shrunk and their refractive index increases in the range of 1.58-1.83 depending on the film composition. The attenuation of the waveguides is not sensitive to changes in composition except for zinc titanium silicate waveguides which have substantially higher attenuation. However, the increase in the attenuation with aging of the waveguides depend upon the composition of waveuides. The addition $Al_2O_3$ or the reduced $SiO_2$ content in the composition appears to slow the deterioration of the waveguides due to the formation of more stable bonds and increased acidity on the film surface. Also, the wavelength dependence of the attenuation of the waveguides varies with composition. The attenuation of the waveguides except for the $65SiO_2{\cdot}35TiO_2$ composition are not Rayleigh scatter limited, suggesting the absorption loss of the waveguides due to the effects of residual carbon and structural defects in the films.

• Journal of Korean Vacuum Science & Technology
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• v.4 no.3
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• pp.81-85
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• 2000

The effects of $NH_3$ flow rate and reactor pressure on Al composition and the interface of AlGaN/GaN heterostructure were studied. Equilibrium partial pressure of Ga and Al over AiGaN alloy was calculated as a function of growth pressure, $NH_3$flow rate and temperature. It was found equilbrium vapor pressure of Al is significantly lower than that of Ga, thus, the alloy composition mainly controlled by Ga partial pressure. We believe that more decomposition of Ga occur at lower $NH_3$ flow rate and higher growth pressure leads to preferred Al incorporation into AlGaN. The alloy composition gradient became larger at AlGaN/GaN heterointerface at higher reactor pressures, higher Al composition and low $NH_3$ flow rate. This composition gradient lowered sheet carrier concentration and electron mobility as well. We obtained an AlGaN/GaN heterostructure with sheet carrier density of ${\sim}2{\times}10^{13}cm^{-2}$ and mobility of 1250 and 5000 $cm^2$/Vs at 300 K and 100 K, respectively.

• Journal of Advanced Navigation Technology
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• v.17 no.6
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• pp.652-657
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• 2013

In this paper the design methode of a separated composition state machine based on the compositive map with two chaotic maps together and the result of that is proposed. The digital circuits of chaotic composition map for the use of chaotic binary stream generator are designed in this work. The discretized truth table of chaotic composition function which is composed of two chaotic functions - the saw tooth function and skewed logistic function - is made out, and also simplefied Boolean algebras of digital circuits are obtained as a mathematical model. Consequently, the digital circuits of the map for chaotic composition function are presented in this paper.

• Annual Conference of KIPS
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• 2012.04a
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• pp.586-589
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• 2012

Web Services have been utilized in a wide variety of applications and have turned into a key technology in developing business operations on the Web. Originally, Web Services can be exploited in an isolated form, however when no single Web Service can satisfy the functionality required by a user, there should be a possibility to compose existing services together in order to fulfill the user requirement. However, since the same service may be offered by different providers with different non-functional Quality of Service (QoS), the task of service selection for Web Service composition is becoming complicated. Also, as Web Services are inherently unreliable, how to deliver reliable Web Services composition over unreliable Web Services should be considered while composing Web Services. In this paper, we propose an approach on a QoS-aware Web Service selection for reliable Web Service composition. In our approach, we select and classify Web Services using Decision Tree based on QoS attributes provided by the client. Service classifier will improve selection of relevant Web Services early in the composition process and also provide flexibility to replace a failed Web Services with a redundant alternative Web Services, resulting in high availability and reliability of Web Service composition. We will provide an implementation of our proposed approach along with efficiency measurements through performance evaluation.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.3
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• pp.891-910
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• 2021

Previous QoS-aware service composition methods mainly focus on how to generate composite service with the optimal QoS efficiently for a single request. However, in the real application scenarios, there are multiple service requests and multiple service providers. It is more important to compose services with suboptimal QoS and maintain the load balance between services. To solve this problem, in this paper, we propose a service composition method, named as dynamically change and balancing composition method (DCBC). It assumes that the QoS of service is not static, and the services can adjust the value of QoS to gain more opportunities to be selected for composition. The method mainly includes two steps, which are the preprocessing step and the service selection step. In the preprocessing step, a backward global best QoS calculation is performed which regarding the static and dynamic QoS respectively; then guided by the global QoS, the feasible services can be selected efficiently in the service selection step. The experiments show that the DCBC method can not only improve the overall quality of composite services but also guarantee the fulfill ratio of requests and the load balance of services.

• Journal of Powder Materials
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• v.26 no.1
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• pp.22-27
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• 2019

In this study, the effects of powder size and composition on the reflectance of Al-Si based alloys are presented. First, the reflectance of Al-Si bulk and powder are analyzed to confirm the effect of powder size. Results show that the bulk has a higher reflectance than that of powder because the bulk has lower surface defects. In addition, the larger the particle size, the higher is the reflectance because the interparticle space decreases. Second, the effect of composition on the reflectance by the changing composition of Al-Si-Mg is confirmed. Consequently, the reflectance of the alloy decreases with the addition of Si and Mg because dendrite Si and $Mg_2Si$ are formed, and these have lower reflectance than pure Al. Finally, the reflectance of the alloy is due to the scattering of free electrons, which is closely related to electrical conductivity. Measurements of the electrical conductivity based on the composition of the Al-Si-Mg alloy confirm the same tendency as the reflectance.

• The Journal of the Convergence on Culture Technology
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• v.4 no.4
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• pp.261-266
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• 2018

This study aimed to provide an overview of artificial intelligence based music composition programs. The artificial intelligence-based composition program has shown remarkable growth as the development of deep neural network theory and the improvement of big data processing technology. Accordingly, artificial intelligence based composition programs for composing classical music and pop music have been proposed variously in academia and industry. But there are several limitations: devaluation in general populations, missing valuable materials, lack of relevant laws, technology-led industries exclusive to the arts, and so on. When effective measures are taken against these limitations, artificial intelligence based technology will play a significant role in fostering national competitiveness.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.3
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• pp.13-21
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• 2022

Seowon is an educational institution of Neo-Confucianism in the Joseon Dynasty and is distributed throughout the country. Such a Seowon has a certain form in the composition and arrangement of buildings. Korean Seowon were recognized as excellent for localization by transforming them according to the local environment. Therefore, it was registered as a World Heritage Site. Museongseowon is located in the village differently from the 8 registered Seowons. However, data and research on the location setting and architectural composition of MuseongSeowon are insignificant, so related research is needed. Therefore, in this study, the appearance of the period when MuseongSeowon was equipped with architectural formality was investigated. This study compared the appearance of MuseongSeowon in Chilkwong-do drawn in 1910 and the present appearance, focusing on the Ganghak area. As a result, the architectural composition of the Seowon was similar to the present appearance after the revision of the Gangdang area in Chilkwong-do. Therefore, the present architectural composition of the Seowon appears to be the same as before 1900. In addition, the location and appearance of Heunghakjae and Myeonamsa, which were currently lost in the Gangsujae area, were partially derived. It seems that seowon played a central role in the village even after 1910. Also, since it is located in the village, the building seems to have a flexible spatial composition.