• Journal of the Korean Ceramic Society
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• v.40 no.4
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• pp.340-345
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• 2003

B $i_2$ $O_3$-Ti $O_2$ composite dielectric ceramics have been prepared by a conventional solid state ceramic route. The composite ceramics were prepared with starting materials of different origin and the microwave dielectric properties were investigated. The sintered ceramics were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray microanalysis, Raman and microwave methods. Structural and microstructural analyses identified two separate phases: Ti $O_2$(rutile) and B $i_2$ $Ti_4$0$_{11}$. The separate grains of titania and bismuth titanate were distributed uniformly in the ceramic matrix. The composition 0.88Ti $O_2$-0.12B $i_2$ $Ti_4$ $O_{11}$ was found to have a Q$\times$f of 9300 GHz (measured at a frequency of 3.9 GHz), a temperature coefficient of frequency, $\tau$$_{cf}$ near zero and a high relative permittivity, $\varepsilon$r of 83. The microwave dielectric properties were measured down to 20$^{\circ}$K K. The quality factor increased on cooling the ceramic samples.les.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.4
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• pp.741-762
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• 2011

Recently, multicast routing protocols become increasingly important aspect in Mobile Ad hoc Networks (MANETs), as they effectively manage group communications. Meanwhile, multimedia and real-time applications are becoming essential need for users of MANET. Thus it is necessary to design efficient and effective Quality of Service (QoS) multicast routing strategies. In this paper, we address the scalability problem of multicast routing protocols to support QoS over MANETs. In particular, we introduce a Position-Based QoS Multicast Routing Protocol (PBQMRP). Basically, the protocol based on dividing the network area into virtual hexagonal cells. Then, the location information is exploited to perform efficient and scalable route discovery. In comparison with other existing QoS multicast routing protocols, PBQMRP incurs less control packets by eliminating network flooding behavior. Through simulation, the efficiency and scalability of PBQMRP are evaluated and compared with the well-known On-Demand Multicast Routing Protocol (ODMRP). Simulation results justify that our protocol has better performance, less control overhead and higher scalability.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.4
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• pp.363-371
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• 2010

In an effort to enhance the quality of feature vector classification and thereby reduce the recognition error rate for the speaker-independent speech recognition, we study the effect of spectral tilt on the Fourier magnitude spectrum en route to the extraction of MFCC. The effect of FIR filtering on the speech signal on the speech recognition is also investigated in parallel. Evaluation of the proposed methods are performed by two independent ways of the Fisher discriminant objective function and speech recognition test by hidden Markov model with fuzzy vector quantization. From the experiments, the recognition error rate is found to show about 10% relative improvements over the conventional method by an appropriate choice of the tilt factor.

• Proceedings of the KOR-KST Conference
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• 1995.05b
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• pp.69-76
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• 1995

Difficulties in riding , driving and parking are a common issue which inevitably appears in city urbanization and city modernization development all over the world. However, those cities differ in controlling the traffic. According to the specific practice in Shanghai, this article presents the various factors which affect the traffic capacity and operation quality . This article also outlines transportation system management technique of overall coordination and comprehensive control in the following seven aspects : controlling traffic motivation : improving traffic distribution : reasonably and scientifically selecting travel mode, travel route and travel time : reinforcing traffic management and road construction. The article finally suggests that the above mentioned points are cost-effective ways of the handling traffic plight for metropolitan transport.

• Journal of the Korea Furniture Society
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• v.28 no.1
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• pp.1-15
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• 2017

Even though, a quality of the daily goods and furniture are improving as increasing living standard, the neglected people have been left behind as ever. However, tools and furniture of everyday life a certain class that are alienated are left to the inconvenience of everyday life such as the difficulty of purchase route or incongruity with the surround living space. The design that can solve this problem is the inclusive design. When we look closely the previous researches on the inclusive design, we can find that researches on public facilities and industrial products are actively carried out based on the principles and features of the inclusive design, but studies in the field of furniture design are very insufficient. In this paper, we try to study the furniture design incorporating the inclusive design and to include specific stratum without alienating it. The research method is centered on product case analysis and suggested furniture design that 'everyone can use together'. This helps designs in realizing their social values by giving everyone the right to live an equal life.

• Geomechanics and Engineering
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• v.14 no.5
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• pp.453-458
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• 2018

Geomechanical parameters are important factors for engineering projects during design, construction and support stages of tunnel and dam projects. Geostatistical estimation methods are known as one of the most significant approach at estimation of Geomechanical parameters. In this study, Azad dam headrace tunnel is chosen to estimate Geomechanical parameters such as Rock Quality Designation (RQD) and uniaxial compressive strength (UCS) by ordinary kriging as a geostatistical method. Also Rock Mass Rating (RMR) distribution is presented along the tunnel. Main aim in employment of geostatistical methods is estimation of points that unsampled by sampled points.To estimation of parameters, initially data are transformed to Gaussian distribution, next structural data analysis is completed, and then ordinary kriging is applied. At end, specified distribution maps for each parameter are presented. Results from the geostatistical estimation method and actual data have been compared. Results show that, the estimated parameters with this method are very close to the actual parameters. Regarding to the reduction of costs and time consuming, this method can use to geomechanical estimation.

• Proceedings of the KOR-KST Conference
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• 1995.05a
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• pp.61-68
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• 1995

Difficulties in riding, driving and parking are a common issue which inevitably appears in city urbanization and city modernization development all over the world. However, those cities differ in controlling the traffic. According to the specific practice in Shanghai, this article presents the various factors which affect the traffic capacity and the operation quality. This article also outlines transportation system management technique of overall coordination and comprehensive control in the following seven aspects: controlling traffic motivation; improving traffic distribution; reasonably and scientifically selecting travel mode, travel route and travel time; reinforcing traffic management and road construction. The article finally suggests that above mentioned points are cost-effective ways of handling traffic plight for metropolitan transport.

• The Korean Journal of Emergency Medical Services
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• v.15 no.2
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• pp.5-14
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• 2011

Purpose: The aim of this study is to identify the legal concept of a license and a qualification for health care personnel. We analyze the appropriateness of the qualification for the first-class paramedics and the sufficiency of 3-year job experience in substitution for college level academic major. Method: We reviewed Laws on Healthcare which stipulate academic and career qualifications for healthcare personnel for whom college-level academic training and job experience to get a license. Results: There is no legal consideration which permits major and educational background substituted by job experience. Only third-class hygienist who graduated from a high school or the equivalent with 3 year job experience can apply for first-class hygienist' national license examination without educational requirements. However, it is nothing to compare with first-class paramedics because the work of hygienist is not directly related to patients care and there is no need of doctor's supervision for hygienist' job. Paramedics have a major role in saving emergency patients in making prompt decision, applying appropriate emergency treatment, securing intravenous route, managing intubation, applying defibrillator, and etc. Conclusion: Ministry of Health & Welfare should grant license to paramedics and annul replacement of academic major background. In addition, it is imperative to broaden the scope of paramedics' job so that they can guarantee patient's life saving in emergency situation with quality major curriculum of college level.

• Journal of Korean Public Health Nursing
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• v.24 no.1
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• pp.5-18
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• 2010

Purpose: The purpose of this study is to understand nurses' perception of visiting nursing services of long-term care insurance. Method: The descriptive survey study involved 188 nurses selected by the convenient sampling of visiting nurses who participated in professional education sessions. Results: Of the 188 participants, 149 (79.3%) were aware of long-term care insurance. Awareness of aspects of long-term care services was 78.7% for facility service, 77.7% for ordinary visiting care service, 85.1% for visiting nursing service and 77.7% for visiting bathing service. Concerning visiting nursing service provision, the majority of the study subjects considered nurse-aid not to be the appropriate route for delivery of services including nasogastric tube exchange, tracheostomy tube management and stitch removal. Conclusion: Continuous evaluation and research on the standards and requirements of the nursing workforce is needed to secure and maintain the high quality of visiting nursing services. Exhaustive studies concerning task division and workforce separation according to nursing services type and level of difficulty should be done to develop the appropriate job description for visiting nursing service staff.

• Journal of Environmental Science International
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• v.22 no.8
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• pp.1043-1052
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• 2013

This study was conducted to investigate the correlations between the $PM_{10}$ concentration trend and meteorological elements in the Gimhae region and analyze the transportation routes of air pollutants through back-trajectory analysis. Among the air quality measuring stations in the Gimhae regions, the $PM_{10}$ concentration of the Sambangdong station was higher than that of the Dongsangdong station. Also, an examination of the relationships between $PM_{10}$ concentration and meteorological elements showed that the greater the number of yellow dust occurrence days was and the lower the temperature and precipitation were, the higher the $PM_{10}$ concentration appeared. Furthermore, a cluster analysis through the HYSPLIT model showed that there were 4 clusters of trajectories that flowed into the Gimhae region and most of them originated in China. The meteorological characteristics of the four clusters were analyzed and they were similar to those of the air masses that influence South Korea. These analyses found that meteorological conditions affect the $PM_{10}$ concentration.