• Title/Summary/Keyword: reinforcing system

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On the Design of Cantilever Type High Speed Towing Carriage with Excellent Acceleration Performance (가속성능이 우수한 외팔보형 고속예인전차의 설계)

  • Kim, Jae Sung;Kim, Hyochul
    • Journal of the Society of Naval Architects of Korea
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    • v.53 no.3
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    • pp.228-236
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    • 2016
  • Extraordinarily the establishment of towing tank has been initiated after the allocation of space at the basement floor of existing building through remodeling procedure. Therefore the asymmetric tank should be unavoidably determined by compromising with the allowable space and existing building structure. Consequently the shape of towing carriage ought to be selected as a cantilever type to match with the given environmental conditions. Finally the major role of the towing tank has been configured on the fundamental research work for the high speed marine vehicles. Due to the limited length of towing tank, it is appeared that the carriage should accelerated with 1.2m/sec2 which is equivalent to twice of the maximum acceleration in ordinary practices on design application of carriage. In such a condition the exerted total power of motor could not be converted to traction force of the carriage without slip for the acceleration. To overcome these difficulties the contact pressure of a horizontal traction wheel to rail has been reinforced by the elastic recovery force of springs on supporting rollers. It is believed that the design experience of the high speed towing carriage under unusual circumferential condition and acceleration barrier could be utilized not only on the design of high speed towing carriage but also on the improvement of existing facilities.

A Study on the Promising Future Biotechnology (바이오 미래유망 연구분야 도출에 관한 연구)

  • Kam, Ju-Sik;Kim, Moo-Woong;Par, Sang-Dai;Hyun, Byung-Hwan
    • Journal of Korea Technology Innovation Society
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    • v.15 no.2
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    • pp.345-368
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    • 2012
  • As science and technology are the core engines of economic and social affairs, it is becoming increasingly necessary to explore new promising technologies in order to secure competitiveness in science and technology with a view to helping upgrade the country's overall competitiveness and promoting industrial development. The governments of major advanced countries provide R&D support for promising future technologies. Even in South Korea, a study is being carried out to set up a model for forecasting future technologies and reinforcing the relevant survey system. This study intends to explore methods of identifying promising future technologies in the bio-science sector, which has emerged as a new growth engine. It will use a text-mining technique to collect and analyze theses in the bio science sector. It will identify key research sectors by analyzing thesis contour lines, and then review promising future key research subjects through in-depth study.

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A Study on Improvement Plans of SMEs Support Policy for Information Security in Korea (국내 중소기업 정보보호 지원 정책 개선 방안에 관한 연구)

  • Jang, Sang-Soo
    • Journal of Convergence for Information Technology
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    • v.10 no.11
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    • pp.332-339
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    • 2020
  • This study aims to analyze problems and deduce improvement plans for information security support policies for SMEs in Korea. To this end, an effective support policy necessary for reinforcing cyber safety nets to enhance the level of information security of domestic SMEs based on the analysis results by analyzing the status and problems of the previous research review and analysis, the current status of information security of SMEs and the information security support policies of major SMEs at home and abroad. I would like to suggest improvement measures. Reinforcement of awareness, legal basis, voluntary capacity building, joint response system, professional manpower and budget support, cyber security construction, untact era support, and regional strategic industry security internalization were suggested. This can be used as the government's information security support policy to raise the level of information security of SMEs in preparation for the post Covid19.

Crock Resistance Properties of Natural Rubber Compounds for Tank Track Pads (군용 전투차량 궤도 pads용 천연고무 배합물의 내크랙성 향상을 위한 연구)

  • Shin, Jung-Eun;Kim, Yu-Seuk;Bae, Jong-Woo;Kim, Won-Ho
    • Elastomers and Composites
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    • v.33 no.5
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    • pp.335-344
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    • 1998
  • In this study, the tearing energy and the rate of crack propagation of natural rubber (NR) compounds were evaluated to improve the crack resistance of tank-track pads. Although the factors affecting the crack resistance properties of NR compounds are various in this experiment, the effects of filler(carbon black) and the crosslinking system were evaluated. When the amount of accelerator is equal to that of sulfur( eg. efficient vulcanization), the compound shows the most excellent in the aged mechanical properties and the crack resistance properties. The ISAF carbon black(CB) having a good reinforcing characteristics was better than any other CB grades in physical properties and processablity. The optimum content was 50phr.

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An Experimental Study for Bond Stress between DFRCC and Carbon FRP Plank Used as a Permanent Formwork (영구거푸집으로 활용한 탄소섬유 FRP 판과 DFRCC 사이의 부착응력에 관한 실험적 연구)

  • Park, Chan-Young;Yoo, Seung-Woon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.6
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    • pp.1687-1694
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    • 2014
  • Recently FRP of carbon fibers is utilized as a repairing and reinforcing material for concrete structures. In this study, the bond performance between CFRP planks and ductile fiber reinforced cementitious composites was evaluated in order to develop a new system of concrete bridge deck to take advantage of the FRP planks of carbon fiber using as a permanent formwork. In order to strengthen the bonding between the FRP and cast-in-place concrete, an epoxy resin circulated in the market generally was fitted with a silica sand. The bond stress of ordinary concrete appeared in 2.11~5.43MPa and the bond stress of ductile fiber reinforced cementitious composites DC1 (RF4000) and DC2 (PP) respectively were 3.91~5.60MPa, 2.92~5.21MPa and the average bond stress of DC3 (RF4000+RSC15) and DC4 (PP+RSC15) were 4.80~5.58MPa, 5.57~5.89MPa.

Asian Dust Transport during Blocking Episode Days over Korea

  • Moon, Yun-Seob;Kim, berly-Strong;Kim, Yoo-Keun;Lim, Yun-Kyu;Oh, In-Bo;Song, Sang-Keun;Bae, Joo-Hyon
    • Journal of Environmental Science International
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    • v.11 no.2
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    • pp.111-120
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    • 2002
  • Asian dust(or yellow sand) occurs mainly in spring and occasionally in winter in east Asia, when the weather conditions are under an upper trough/cut-off low and surface high/low pressure system during blocking episode days associated with the stationary patterns of the upper level jet stream. The transport mechanism for Asian dust during the blocking episode days in spring 2001 was analyzed using the TOMS aerosol index and meteorological mesoscale model 5(MM5). Based on the E vector, an extension of an Eliassen-Palm flux, the blocking episode days were found to be associated with the development of an upper cut-off low and surface cyclones. Concurrently, the occurrence of dust storms was also determined by strong cold advection at the rear of a jet streak, which exhibited a maximum wind speed within the upper jet stream. As such, the transport mechanism for Asian dust from China was due to advection of the isentropic potential vorticity(IPV) and isentropic surfaces associated with tropopause folding. The transport heights for Asian dust during the blocking episode days were found to be associated with the distribution of the isentropes below the IPV At the same time, lee waves propagated by topography affected the downward motion and blocking of Asian dust in China. The Asian dust transported from the dust source regions was deposited by fallout and rain-out with a reinforcing frontogenesis within a surface cyclone, as determined from satellite images using TOMS and GMS5. Accordingly, these results emphasize the importance of forecasting jet streaks, the IPV, and isentropes with geopotential heights in east Asia.

Influence of Sintering Additives and Temperature on Fabrication of LPS-SiC (액상소결법에 의한 탄화규소 제조시 소결조제와 온도의 영향)

  • JUNG HUN-CHAE;YOON HAN-KI
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2004.11a
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    • pp.266-270
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    • 2004
  • SiC materials have been extensively studied for high temperature components in advanced energy system and advanced gas turbine because it has excellent high temperature strength, low coefficient of thermal expansion, good resistance to oxidation and good thermal and chemical stability etc. However, the brittle characteristics of SiC such as low fracture toughness and low strain-to fracture still impose a severe limitation on practical applications of SiC materials. For these reasons, SiC/SiC composites can be considered as a promising for various structural materials, because of their good fracture toughness compared with monolithic SiC ceramics. But, high temperature and pressure lead to the degradation of the reinforcing jiber during the hot pressing. Therefore, reduction of sintering temperature and pressure is key requirements for the fabrication of SiC/SiC composites by hot pressing method. In the present work, monolithic Liquid Phase Sintered SiC (LPS-SiC) was fabricated by hot pressing method in Ar atmosphere at $1800^{\circ}C$ under 20MPa using $Al_2O_3,\;Y_2O_3\;and\;SiO_2$ as sintering additives in order to low sintering temperature and sintering pressure. The starting powder was high purity $\beta-SiC$ nano-powder with all average particle size of 30mm. The characterization of LPS-SiC was investigated by means of SEM and three point bending test. Base on the composition of sintering additives-, microstructure- and mechanical property correlation, tire compositions of sintering additives are discussed.

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A Study on Reinforcement and Development of Course Programs in Department of Food Science and Nutrition Related Studies 1st Report -Based on Survey of Dietitians and Professors - (영양사 배출 관련학과의 전공과목 강화 및 개발에 관한 연구 제1보 -영양사 및 대학 교수의 전공과목 강화에 대한 의견 조사)

  • 박명희;최봉순
    • Journal of the East Asian Society of Dietary Life
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    • v.6 no.1
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    • pp.1-16
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    • 1996
  • This study was conducted to obtain basic data for reinforcing and developing course programs in department of Food Science and Nutrition. For this purpose, data was collected from dietitians and professors who work at 2-and 4-year colleges. Results are as follows. 1. Many respondents (95.7%) support that It Is desirable to separate dietitian license into two types. Reasons are (1) specific knowledge required by job type is different(29.5%), and (2) to increse job performance (29.3%). 2. Most respondents(95.4%) agree that course programs are needed to be revised. Because (1) current programs are inadequate to provide specific knowledge required at field work (67.8%), and (2) the programs are not helpful to increase job performance of dietitians (54.1%). 3. Respondents of dietitians want to extend applied science area(37.7%) and reinforce lab training (63.1%), as principles of program revision. 4. Course titles which need to be reinforced are Internship(95.8%) and Lap training(67.8%). 5. Specialized areas which need to be reinforced are Food Service Managemant and Practical Training(90.9%), Nutrition Education and Guide(88.9%), Public Health Nutrition(79.0%), Basic Area for Clinics(85.6%), Basic area for Education and Counselling(87.1%), and Cooking Science(77.5%) 6. Courses which are needed to be reinforced by respondents(over 75% agree) are Computer Management for Food Service, Counselling, Nutrition and Disease, Diet Therapy, Quantity Cooking, Internship, Public Health (Health Care), Community Nutrition(Environment and Nutrition), Clinical Nutrition, Psychology, and Communication.

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The Impact of Child Care Type on Infant's Developmental Outcome: Focusing on the Care Type of at Home Nurturing and Daycare Center (영아기 돌봄유형이 영아발달수준에 미치는 영향에 관한 연구: 가정내 돌봄과 어린이집 돌봄의 비교를 중심으로)

  • Choi, Sang Seol
    • Korean Journal of Child Education & Care
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    • v.18 no.1
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    • pp.53-76
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    • 2018
  • The purpose of this study was to investigate the effect of child care type on infant's developmental outcomes assessed by K-ASQ, focusing on the child-centric role of nurture policy. For this, this study categorized child care type into types including home nurturing, child care center, and subtypes of each category. The findings of multiple regression analysis using the first-third wave data of Panel Study of Korean Children(PSKC) are as follows. First, the child care center experience had rather positive effect on the development of all abilities in the infants comparing to home nurturing. Second, the time of attending child care center was differently related to the development of motor, communication, and personal-social skill in infanthood. Finally, the accreditation of child care showed a difference only in terms of social development of infants. In conclusion, even if the experience of using child care center has positive impact on infant's developmental level, it is still in need of improving service quality such as reinforcing accreditation system.

A Study on the Appropriateness of Health Insurance Fee in Main Nursing Practices (주요 간호활동의 건강보험 수가 적절성에 관한 연구)

  • Kim, Yunmi;Kim, Kyungsook;Park, Mi Mi;Kim, In Sook;Kim, Mi Young
    • Journal of Korean Clinical Nursing Research
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    • v.23 no.2
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    • pp.236-247
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    • 2017
  • Purpose: This study was to present improvement strategy and the problems of the nursing fee in national health insurance system. Methods: A total of 23 nursing activities performed by nurses were selected. Data were collected the relative value score and criteria of the Health Insurance Review & Assessment Agency. Sixty clinical nursing experts panels were composed and nursing time surveyed self-reported method. The actual fee was calculated through the nursing time, relative value score and actual labor costs. Nextly, the labor costs analyzed was compared with that in the national health insurance. Results: Although the practices were mainly performed by the nurse, other occupations have been recorded as main practitioners and the time of the nursing activity is partially improperly reflected. Additionally, although the nurse practiced mainly in glucose (semi-quantitative) test, it was confirmed that the principal practitioner was described as a clinical pathologist. The the labor cost gap was estimated that is 9.3 times (median) and 11.9 times (average) in this analysis. Conclusion: This study suggests that it is necessary to legislate a policy that can improve the quality of clinical nursing by reinforcing the appropriateness and improving nursing fee through reflection of the actual time spent for nursing care.