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Design Positioning of the Korea Railway (한국철도차량의 디자인 포시셔닝)

  • Lee, Hee-Yup;Kim, Chang-Hyun
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.1268-1275
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    • 2007
  • The Korea railway design trends has been developed by the change of the society and culture through the consideration of the history of railway. The railway design trends is as the vehicles in the external form of railways, instantly means to plan and create the value added something like the form of the exterior design. The railway design has been changing form instinctive methods to settle the mass transport of the early days, to sensitive methods to pursue the railway culture centering around human being. As dividing by the style's change of railway in image scale aspects between 1800's and 2005 according to the life environment into the external nation, there are big differences so that is to study the development history of the railway design accordingly each nation (Korea, United Kingdom, Germany, France, Japan) and the style's change, to confirm into the design applied in society and culture needs, and to analyze by a year in changes of the environment and the railway design history. This paper analyzed railway introduced as railway models by top 4 nation (United Kingdom, Germany, France, Japan) and Korea in the past years(1800-2005) for their Korea railway design trends by image scale positioning.

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Intelligent management system for tunnel under construction using ITIS (Intelligent Tunnelling Information System)

  • Kim Changyong;Hong Sungwan;Bae Gyujin;Kim Kwangyeom
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.170-175
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    • 2003
  • Ground and rock mass considered in tunnelling have characteristics such as uncertainty, heterogeneity and structural complexity because they have been formed undergoing various geological events for a long period. So, it is difficult for engineers to predict behaviors of rock mass in tunneling. In the paper the authors describe the development of an integrated expert system prototype for site investigation, design and construction in tunnelling and introduce the case applying this system to the tunnel construction site under construction. Geostructure Research Group in Korea Institute of Construction Technology (KICT) has developed the system during the past 4 years. The system mainly consists of several modules which is related to the design, construction and management of tunnelling. The test site, Neung-dong tunnel is located in Ulsan, Korea. The geology map shows it may confront big fault zone whose width is over kilometres. With the networking system of ITIS, various information of face mapping, monitoring and other construction task can be transmitted into the database and GIS Server at real time. And necessary analyses can be carried out with the modules equipped in the system.

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Appropriate Sewerage Systems for Korea (우리나라 적합 하수도시설 및 관리방안)

  • 이상은
    • Journal of environmental and Sanitary engineering
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    • v.7 no.2
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    • pp.37-52
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    • 1992
  • Since the first sewage treatment plant was constructed in 1976, the sewerage systems of Korea have been rapidly expanded. As of the end of 1991, 22 sewage treatment plants with total capacity of 5.4 million tons/day are in operation which is equivalent of 3395 total daily sewage generation. Total extension of sewer 39.534 km in 1990 which is 55% of the target extension for the year 2001. However, the most sewage treatment plants employ activated sludge process which may not be suitable for medium and/or small scale plants. The poor existing sewer systems do not effectively collect and transport sewage to adversely affect the function of sewage treatment plant. To select the appropriate treatment system, the cities are classified into 3 categories such as large and medium size inland cities, small size cities and coastal cities. Considering the criteria suggested during this study, appropriate treatment processes were selected for each category. Conventional activated sludge process and step aeration process were found to be the most appropriate for big inland cities while biological nutrient removal processes should be considered for the cities discharge the effluent to lakes or reservoirs. RBC or Oxidation Ditch process might be appropriate for the medium size cities while several processes which do not require skilled operation and maintenance were suggested for the small cities. Ocean discharge after primary treatment can be considered for some east coast cities, Appropriate methodology to rehabilitate the existing sewers and strategy to convert combined sewer system to separate sewer system were proposed. This paper also include the appropriate management system for industrial wastewater, sludge and nightsoil.

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Dental Hygiene Major student's Curriculum Satisfaction and Perception on Their Occupation in Kyungnam Area (경남지역 치위생과 학생들의 전공교육에 대한 만족도 및 취업 인식도)

  • Choe, Jeung-Mi
    • The Journal of Korean Society for School & Community Health Education
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    • v.10 no.2
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    • pp.95-108
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    • 2009
  • Objectives: This study is to explore school related adjustmental perception to department of dental hygiene of college students and images of employment. Methods: We surveyed 355 students at department of dental hygiene in Kyungnam and Busan during the period from August to October, 2009 using a self-administered questionnaires. Collected data were analyzed using SPSS 14.0. Results: Students were barely satisfied with the curricula. More than a half respondents said they were fairly good in their major field. Less than a half of the students(47.4%) said they would recommend their junior classmates to take their major. Many students (7d2.3%) wanted to have a job in big cities after graduation. More than a half students (50.8%) wanted to work at general hospitals rather than private clinics. Conclusion: Concerns and support for the students should be provided and more strong public relationship is required. And development of a career counseling program in Department of Dental Hygiene are necessary.

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The Effect of Commercial Doenjangs(Korean soybean paste) on the Sponge Cake Making (시판 된장 첨가가 스폰지 케이크 제조에 미치는 영향)

  • 오현주;김창순
    • Korean journal of food and cookery science
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    • v.20 no.4
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    • pp.387-395
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    • 2004
  • The effect of commercial Doenjangs (Korean soybean pastes) on sponge cake making was studied. When Doenjang was added to e99 foams at levels of 5, 10, 15 and 20%, there were no big differences in viscosity or stability of egg foams up to 15%, and thus in cake volume index, compared to those of control (without Doenjang). In the results of preference rank test, cake with 10% Doenjang was preferred to the other cakes. Therefore, it was decided that the addition of 10% Doenjang was suitable for sponge cake making. When seven commercial Doenjang products were used at 10%, there were differences in physical and sensory properties. The decreased viscosity of egg foams reduced their stability and so decreased the quality of the sponge cakes with low volume index and low texture scores. The use of Doenjangs improved the flavor of sponge cake and so countervailed the undesirable egg flavor. Especially, “C” Doenjang product, which increased the viscosity and stability of egg foams, produced good foaming ability and the highest physical and sensory quality, thus the higher overall acceptable scores than the control. It was probably due to its high amount of protein hydrolysate above 10-KDa. Consequently, the suitable amount of Doenjang was fixed at 10% and “C” Doenjang product was chosen as the best among the commercial products for sponge cake making.

NUMERICAL CALCULATION OF TWO FLUID SOLAR WIND MODEL

  • KIM S.-J.;KIM K.-S.;MOON Y.-J.;CRO K.-S.;PARK Y. D.
    • Journal of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.55-59
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    • 2004
  • We have developed a two fluid solar wind model from the Sun to 1 AU. Its basic equations are mass, momentum and energy conservations. In these equations, we include a wave mechanism of heating the corona and accelerating the wind. The two fluid model takes into account the power spectrum of Alfvenic wave fluctuation. Model computations have been made to fit observational constraints such as electron($T_e$) and proton($T_p$) temperatures and solar wind speed(V) at 1 AU. As a result, we obtained physical quantities of solar wind as follows: $T_e$ is $7.4{\times}10^5$ K and density(n) is $1.7 {\times}10^7\;cm^{-3}$ in the corona. At 1 AU $T_e$ is $2.1 {\times} 10^5$ K and n is $0.3 cm^{-3}$, and V is $511 km\;s^{-1}$. Our model well explains the heating of protons in the corona and the acceleration of the solar wind.

New Record of the Snake Mackerel, Gempylus serpens (Perciformes: Gempylidae) from Jeju Island, Korea (한국 제주도에서 채집된 갈치꼬치과(Gempylidae) 어류 1 미기록종, Gempylus serpens)

  • Myoung, Se Hun;Ryu, Jung-Hwa;Kim, Jin-Koo
    • Korean Journal of Ichthyology
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    • v.25 no.3
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    • pp.178-181
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    • 2013
  • A single specimen (506 mm SL) of Gempylus serpens, belonging to the family Gempylidae, order Perciformes, was firstly collected from Jeju Island, Korea in April 2013. This specimen was characterized by having the lower jaw protruded than upper jaw; three big fangs on upper jaw; five dorsal finlets and seven anal finlets; two lateral lines split at the dorsal origin, upper line interrupted at the end of the first dorsal fin, but lower line extend to the caudal fin base. The new Korean name "Se-jang-gal-chi-ggo-chi-sok" is proposed for the genus Gempylus, and "Se-jang-gal-chi-ggo-chi" for the species G. serpens.

Design of 1.9GHz CMOS RF Up-conversion Mixer (1.9GHz CMOS RF Up-conversion 믹서 설계)

  • Choi, Jin-Young
    • Journal of IKEEE
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    • v.4 no.2 s.7
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    • pp.202-211
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    • 2000
  • Utilizing the circuit simulator SPICE, we designed a 1.9GHz CMOS up-conversion mixer and explained in detail the simulation procedures including device modeling for the circuit design. Since the measured characteristics of the chip fabricated using the $0.5{\mu}m$ standard CMOS process had shown a big deviation from the characteristics expected by the original simulations, we tried to figure out the proper reasons for the discrepancies. Simulations considering the discovered problems in the original simulations have shown the validity of the simulation method tried for the design. We have shown that the utilized standard CMOS process can be used for the implementation of the chip characteristics similar to those of the equivalent chip fabricated using the GaAs MESFET process.

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A Study on Measuring Technique of Electromagnetic Wave Absorbing Characteristics of Microwave Absorbers (전파흡수체의 전파흡수특성 측정기법에 관한 연구)

  • 김동일;안영섭;정세모
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.4 no.1
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    • pp.10-19
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    • 1993
  • As a method to measure the absorbing characteristics of microwave absorber, the various microwave measuring method can be used fundamentally. There is, however, a big problem in measuring errors, since the wavelength of microwave such as used for radar is very short. Therefore, this research aimed to design and fabricate a converting adaptor of 20mm .PHI. coaxial tube from a Type - N connector to $20mm\phi$ coaxial tube and to use it for evaluating absorption characteristics of microwave absorber. Furthermore, the measurements of absorbing characteristics and material constants have been performed and reviewed, which were carried out by using the coaxial tube and by using rectangular waveguide, res- pectively. As a result, the validity of the proposed measuring method has been confirmed.

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Production Scheduling for a Two-machine Flow Shop with a Batch Processing Machine (배치처리기계를 포함하는 두 단계 흐름생산라인의 일정계획)

  • Koh, Shie-Gheun;Koo, Pyung-Hoi;Kim, Byung-Nam
    • Journal of Korean Institute of Industrial Engineers
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    • v.34 no.4
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    • pp.481-488
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    • 2008
  • This paper deals with a scheduling problem for two-machine flow shop, in which the preceding machine is a batch processing machine that can process a number of jobs simultaneously. To minimize makespan of the system, we present a mixed integer linear programming formulation for the problem, and using this formulation, it is shown that an optimal solution for small problem can be obtained by a commercial optimization software. However, since the problem is NP-hard and the size of a real problem is very large, we propose a number of heuristic algorithms including genetic algorithm to solve practical big-sized problems in a reasonable computational time. To verify performances of the algorithms, we compare them with lower bound for the problem. From the results of these computational experiments, some of the heuristic algorithms show very good performances for the problem.