• 제목/요약/키워드: gradual increasing

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한.중 컴퓨터 부품산업의 경쟁력 비교분석 (A Comparative Analysis on Competitiveness for Computer Parts Industry between Korea and China)

  • 김지용;이창현
    • 통상정보연구
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    • 제9권2호
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    • pp.423-439
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    • 2007
  • The purpose of this study was to analyze market competitiveness of Korean and Chinese computer parts industry in the between two countries' market by using Index of Export Bias and Market Comparative Advantage Index. For attaining the purpose of study, we classified the computer parts which exported to the two countries' market and the imported products as the memory devices and input/output peripheral devices. Analyzing period was 2001-2006. The analysis of Korean results of Index of Export Bias indicated that memory devices represented low overall numerical value and the Chinese results of Index of Export Bias indicated that memory devices represented high gradual numerical value. On the other hand, Korean input/output peripheral devices have been increasing steadily for analysis period and China input/output peripheral devices have been decreasing steadily for analysis period. Additional results indicated that the Korean and China computer parts which gained market competitiveness between two countries market were as follows. Korean memory devices have been losing competitiveness in the China market steadily and Chinese memory devices have been acquire competitiveness in the Korean market gradually. In input/output peripheral devices case, Korean products represented powerful competitiveness in the China market and Chinese products have been gaining competitiveness in the Korea market.

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PKI 기반 홈 네트워크 시스템 인증 및 접근제어 프로토콜에 관한 연구 (A Study for PKI Based Home Network System Authentication and Access Control Protocol)

  • 이영구;김정재;김현철;전문석
    • 한국통신학회논문지
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    • 제35권4B호
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    • pp.592-598
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    • 2010
  • 홈 네트워크 시스템은 각종 외부 위협요소로부터의 사이버 공격 대상이 될 수 있을 뿐만 아니라 해킹, 악성코드, 웜 바이러스, DoS공격, 통신망 도청 등의 보안취약성을 가지고 있다. 그래서 홈 네트워크상에서 해당 사용자의 자산 및 개인정보를 보호할 수 있는 보안 프로토콜의 필요성은 점차 증대되어가고 있다. 따라서 본 논문에서는 공개키 인증서를 이용하여 사용자를 인증하고 인증된 정보를 기반으로 해당 기기에 대한 권한을 차등 부여함으로서 허가 받지 않은 사용자로부터의 댁내 자산 및 개인 정보를 보호할 수 있는 사용자 인증과 접근 제어 기술을 이용한 홈 네트워크 보안 프로토콜을 설계하고 제안한다.

Effects of Heavy Metals on Plant Growths and Pigment Contents in Arabidopsis thaliana

  • Baek, Seung-A;Han, Taejun;Ahn, Soon-Kil;Kang, Hara;Cho, Myung Rae;Lee, Suk-Chan;Im, Kyung-Hoan
    • The Plant Pathology Journal
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    • 제28권4호
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    • pp.446-452
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    • 2012
  • The effect of heavy metals on seedling growth and pigment levels was studied in Arabidopsis using essential (Cu, Mn, and Zn) and non-essential metals (Pb and Hg). Generally increasing the concentrations of the metals resulted in a gradual decrease in root and shoot lengths, a decrease in chlorophylls, an increase in anthocyanins and a fluctuation in carotenoid content depending on the metal types. The toxicity of the metals decreased in the following order: Cu > Hg > Pb > Zn > Mn. Among the five metals, Cu was exceptionally toxic and the most potent inducer of anthocyanins. Pb induced the smallest quantity of anthocyanins but it was the strongest inducer of carotenoids. It suggests that the Cu-stressed Arabidopsis may use anthocyanins as its main antioxidants while the Pb-stressed Arabidopsis use carotenoids as its main protectants. All of the five metals induced an accumulation of anthocyanins. The consistent increase in anthocyanin content in the metal-stressed Arabidpsis indicates that anthocyanins play a major role in the protection against metal stresses.

노화촉진 생쥐에서 노화에 따른 활성산소 생성 및 항산화능의 변화 (Age-associated Alteration in the Hapatic Superoxide Generation and Antioxidant Activities in the Senescence-accelerated Mice)

  • 정해영;김윤경
    • 약학회지
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    • 제36권5호
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    • pp.460-468
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    • 1992
  • Several bichemical parameters related to free radicals were estimated in senile-prone (P) and resistant(R) strains of male senescence-accelerated mice(SAM) at 2, 5 and 11 months of age. The superoxide generation was increased with age in SAM-R/1 and SAM-P/2. Compared to SAM-R/1, more generation of superoxide was significantly noted in the SAM-P/2 liver. The activities of Cu/Zn-superoxide dismutase and catalase were decreased during aging and these activities in SAM-P/2 were significantly lower than in SAM-R/l liver. The activities of glutathione S-transferase were varied with aging, whereas SAM-P/2 showed lower levels compared to SAM-R/l. The gradual decreases of glutathione, protein bound-SH and nonprotein bound-SH contents were noted with increasing age. SAM-P/2 liver contained lesser amounts of glutathione and nonprotein bound-SH compared to SAM-R. In conclusion, superoxide generation was increased whereas the antioxidant enzyme activities were decreased during aging in SAM-R/1. In addition, SAM-P/2 strain showed more superoxide generation and less antioxidant enzyme activities than SAM-R/1 in the liver, thus we assume that these factors might accelerate the senescence of SAM-P/2 strain.

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Effect of carbonization temperature on crystalline structure and properties of isotropic pitch-based carbon fiber

  • Kim, Jung Dam;Roh, Jae-Seung;Kim, Myung-Soo
    • Carbon letters
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    • 제21권
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    • pp.51-60
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    • 2017
  • Isotropic pitch-based fibers produced from coal tar pitch with the melt-blowing method were carbonized at temperatures ranging from 800 to $1600^{\circ}C$ to investigate their crystalline structure and physical properties as a function of the carbonization temperature. The in-plane crystallite size ($L_a$) of the carbonized pitch fiber from X-ray diffraction increased monotonously by increasing the carbonization temperature resulting in a gradual increase in the electrical conductivity from 169 to 3800 S/cm. However, the variation in the $d_{002}$ spacing and stacking height of the crystallite ($L_c$) showed that the structural order perpendicular to the graphene planes got worse in carbonization temperatures from 800 to $1200^{\circ}C$ probably due to randomization through the process of gas evolution; however, structural ordering eventually occurred at around $1400^{\circ}C$. For the carbonized pitch powder without stabilization, structural ordering perpendicular to the graphene planes occurred at around $800-900^{\circ}C$ indicating that oxygen was inserted during the stabilization process. Additionally, the shear stress that occurred during the melt-blowing process might interfere with the crystallization of the CPF.

농촌지역 보건지소 건축의 특성에 관한 연구 - 익산시 보건소 관할 지소를 중심으로 - (A Study on the Architectural Characteristics of the Health Care Center Branch in Rural Area Ik-san city)

  • 이동숙;김은영;윤충열
    • 한국농촌건축학회논문집
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    • 제19권4호
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    • pp.9-16
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    • 2017
  • There are an increasing number of healthcare facilaties, especially branch offices, in rural areas to serve the aging population living there. However, there has been a gradual decline in the ratios of recognition, satisfaction and utilization by people who live in the regions. A significant reason of declining the ratios should be the population decline, but the most of population hierarchy shows the groups of elderly people over 60. This result appears to be limited to visit the public health centers. According to the result of population hierarchy, a branch office of public health center has been re-established as a complex welfare facility which can be fulfilled in the functions of basic medical supports and cultural supports. This research is focused on collecting the meaningful information of the status of physical facilities and utilization with 15branch offices of public health care centers in the rural regions near the city of Ik-San city. In addition, this research has a purpose of getting fundamental data for future architectural plans of the branch offices in rural regions with the results about the status of facility operation systems and users' needs.

친환경(親環境) 쌀농업체계(農業體系)로의 전환(轉換)과 식량수급정책(食糧需給政策)의 조정문제(調整問題) (Adoption of Environment-Friendly Rice Farming System and Adjustment of Food Self-Sufficiency Policy)

  • 권용대
    • 농업과학연구
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    • 제28권1호
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    • pp.48-58
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    • 2001
  • This study was conducted to investigate the effects of environmental sound rice farming method on the productivity of rice industry which may result in impacts on the staple food securities. Recently fanners have been concerned about adopting new rice cultivation method such as organic and low input farming system in which fertilizer and pesticide can be substantially reduced so as to alleviate the burden of agro-ecosystem. However, It has been argued about whether or not there are negative impacts on the self sufficiency rate of food, income of farm household and technological adaptability. Therefore this study examined the productivity trend of environmental rice farming system and predicted the long term rice self-sufficiency rate when environmental rice farming system are adopted by assuming various scenarios. It was estimated that rice self-sufficiency rate can be decreased up to 52.2% by 2010. Based on the analysis of results, policy recommendations for environmentally sound rice farming were suggested as follows: 1) gradual adopting and transferring of environmental rice cultivation method, 2) increasing profitability of rice growing fanners 3) developing the farm level technology specific to Korean farming condition, 4) institutionalization of direct payments for encouraging environmental rice fanning.

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박육구상흑연주철에 있어서 Mo 첨가 및 주물두께의 영향에 관한 연구 (Study on the Effect of Mo Addition and Casting Thickness on the Mechanical Properties of Thin Ductile Cast Iron)

  • 송병우;최양진;김영환;박용진
    • 한국주조공학회지
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    • 제13권2호
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    • pp.175-186
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    • 1993
  • In this study, the effect of Mo addition on the microstructure and mechanical properties of ductile cast iron have been investigated. The amounts of Mo and the thickness of specimen have been varied from 0 to 4.79wt% and 13mm, 10mm and 6mm, respectively. As the casting thickness decreases, the average size of spheroidal graphite is decreased and the hardness increases. By increasing the Mo content, the tensile strength of ferrite and pearlite matrix increases and shows maximum which is about $30{\sim}40%$ higher than ordinary ductile cast iron. After the maximum, adding more Mo results in gradual transformation of ferrite and pearlite to bainite and thus tensile strength decreases again. The elongation decreases continueously with Mo content. The addition of Mo about $0.5{\sim}1.0wt%$ improves the wear resistance and tensile strength of thin ductile cast iron.

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외국 의과대학에서의 성과중심교육과정 개발 (The Development of Outcome-Based Curriculum in Medical Schools Outside Korea)

  • 한재진
    • 의학교육논단
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    • 제15권1호
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    • pp.19-24
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    • 2013
  • In medicine, rapid changes in information, technology, socio-economic interests, and globalization affect the medical education focused on the competencies of doctors, and the number of medical schools that are adopting an outcome-based curriculum (OBC) is increasing worldwide. This paper introduces the OBC model of 5 trailblazing medical schools from the UK, US, and Australia, comparing their unique features, followed by brief comment about Canada and the EU as well. On developing an OBC, the process of establishing the top outcomes for graduates is similar and the outcomes comprise knowledge, skills, and attitudes about science, patients, colleagues, society, and themselves. Implementing the outcomes down into the sub-levels of the curriculum is much more complicated and time-consuming. Assessing the achievement of every outcome is essential and requires the use of many tools in addition to the traditional written examination. From the perspective of adult learning theory, self-directed learning, team-learning, and individual and flexible achievement are tested and executed in an OBC. The gradual expansion and further innovation of an OBC is expected so that tomorrow's doctors will be able to meet the challenges of the future.

The Clinical Effects of Dendropanax Morbifera on Postmenopausal Symptoms: Review Article

  • Kim, Mijin;Park, Yoo Jin;Lim, Hee-Sook;Lee, Hae-Hyeog;Kim, Tae-Hee;Lee, Bora
    • Journal of Menopausal Medicine
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    • 제23권3호
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    • pp.146-155
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    • 2017
  • Postmenopausal women aged 50s generally experience gradual changes in body such as decline in antioxidant and estrogen levels as the body ages. To overcome these aging-associated changes, the needs for health functional foods are increasing. Dendropanax morbifera (DM) have antioxidant effects, anti-inflammatory against cancer cells, antidiabetic, and antiatherogenic effect which are associated with postmenopausal symptoms. We analyzed clinical effects of DM on aging-related symptoms by reporting their antioxidant, anticancer and inflammatory activity, etc. and their bioactivity. Data sources EMBASE, SCOPUS, PubMed, Web of Science, and Google Scholar databases were searched up to August 2016 for studies investigating medicinal plants in prevention and treatment of diabetes. The search terms were "Dendropanax morbifera". The reference lists of articles were also reviewed for additional relevant studies. Extracts of DM have various efficacy such as antioxidant, anti-cancer, anti-inflammatory activity and anti-thrombotic effect.