• 제목/요약/키워드: 지식 지도

Search Result 4,956, Processing Time 0.038 seconds

Effect of Vanadium Addition on the Cavitation Erosion Resistance of Fe-Cr-Ni-Si-C Hardfacing Alloy (Fe-Cr-Ni-Si-C계 경면처리 합금의 Cavitation Erosion 저항성에 미치는 Vanadium 첨가의 영향)

  • 김경오;김준기;장세기;김선진;강성군
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 1998.11a
    • /
    • pp.72-72
    • /
    • 1998
  • 원자력발전소 1차계통내 밸브의 경면처리(hardfa따1잉에 사용되는 재료는 $90~343^{\circ}C$의 고온과 높은 접촉응력 그리고 급격한 압력변화가 일어나는 환경에서 사용되기 때문에 내마모성과 내식성 그리고 cavitation erosion 저항성이 우수한 Co계 Stellite 합금이 현재 사용되어진다. 그러나 Co가 원력발전소 1차계통의 방사선장을 형성하는 주요 원소로 알려지면서 S Stellite 합금을 대체할 수 있는 Fe계 경면처리용 합금을 개발하려는 연구가 진행되고 있다. 현재 Fe계 경면처리용 합금의 개발은 적절환 팝금원소를 첨가하여 적충결함에너지를 낮춤 으로써 전위의 교차슬립을 억제하여 표면을 경화시키고, 소성변형을 억제하여 마모저항성을 향상시키려는 방법으로 연구가 진행되고 있다. 본 연구에서는 Fe-Cr-Ni-Si-C 합금에 Fe계 합금의 적충결함에너지를 감소시키는 것으로 알려진 vanadium을 0, 1, 2wt%첨가하여 첨가량의 변화가 cavitation erosion 저항성에 미치 는 영향을 조사하였다. Cavitation erosion 실험은 초음파를 이용하여 미세한 기포를 발생시키는 vibratory type으로 A ASTM G-32 규격에 따라 제작된 실험장치를 이용하여 $25{\pm}2^{\circ}C$의 온도의 증류수 속에 잠긴 상태에서 실시하였다. 시면은 지름 16mm, 두게 7mm의 버턴형태로 vanadium 첨가량을 변화시킨 조성을 아크 용융 방법을 이용하여 제작하였으며 hom끝단부에 부착하여 cavitation e erosion 저항성 살험을 하였다. 시편의 cavitation erosion 실험시간에 따른 무게감소량을 측 정하였으며 cavitation erosion 시킨 시편의 표면을 SEM으로 관찰하였다.겨지는 열전달 매체액 과 신규 부식억제제가 적용된 시스템 등 객관적으로 확인된 부식억제제 시스랩에 대 하여 다양한 평가 방법을 동원 비교분석하고자 하였다. 실험은 KSM 2142에 의한 무게감량법, 분극곡선 측정에 의한 $E_P$(공식개시전위), $E_R$(재부동태화전위) 측정, 시간에 따른 자연전위 변화 측정 빛 이때의 부식속도(선형분극법), 인위적인 피막 파괴 전,후 의 전위 변화 및 부식속도 측정법에 의한 국부부식 발달 저지능 등을 평가하여 각 실험결과를 비교분석하여 보았다. 수록 민감하여 304 의 IGSCC 와 매우 유사한 거동을 보인다. 본 강연에서는 304 와 600 의 고온 물에서 일어나는 IGSCC 민감도에 미치는 환경, 예민화처리, 합금원소의 영향을 고찰하고 이에 대한 최근의 연구 동향과 방식 방법을 다룬다.다.의 목적과 지식)보다 미학적 경험에 주는 영향이 큰 것으로 나타났으며, 모든 사람들에게 비슷한 미학적 경험을 발생시키는 것 이 밝혀졌다. 다시 말하면 모든 사람들은 그들의 문화적인 국적과 사회적 인 직업의 차이, 목적의 차이, 또한 환경의 의미의 차이에 상관없이 아름다 운 경관(High-beauty landscape)을 주거지나 나들이 장소로서 선호했으며, 아름답다고 평가했다. 반면에, 사람들이 갖고 있는 문화의 차이, 직업의 차 이, 목적의 차이, 그리고 환경의 의미의 차이에 따라 경관의 미학적 평가가 달라진 것으로 나타났다.corner$적 의도에 의한 경관구성의 일면을 확인할수 있지만 엄밀히 생각하여 보면 이러한 예의 경우도 최락의 총체적인 외형은 마찬가지로 $\ulcorner$순응$\lrcorner$의 범위를 벗어나지 않는다. 그렇기 때문에도 $\ulcorner$

  • PDF

A Methodology for Translation of Operating System Calls in Legacy Real-time Software to Ada (Legacy 실시간 소프트웨어의 운영체제 호출을 Ada로 번역하기 위한 방법론)

  • Lee, Moon-Kun
    • The Transactions of the Korea Information Processing Society
    • /
    • v.4 no.11
    • /
    • pp.2874-2890
    • /
    • 1997
  • This paper describes a methodology for translation of concurrent software expressed in operating system (OS) calls to Ada. Concurrency is expressed in some legacy software by OS calls that perform concurrent process/task control. Examples considered in this paper are calls in programs in C to Unix and calls in programs in CMS-2 to the Executive Service Routines of ATES or SDEX-20 other software re/reverse engineering research has focused on translating the OS calls in a legacy software to calls to another OS. In this approach, the understanding of software has required knowledge of the underlying OS, which is usually very complicated and informally documented. The research in this paper has focused on translating the OS calls in a legacy software into the equivalent protocols using the Ada facilities. In translation to Ada, these calls are represented by Ada equivalent code that follow the scheme of a message-based kernel oriented architecture. To facilitate translation, it utilizes templates placed in library for data structures, tasks, procedures, and messages. This methodology is a new approach to modeling OS in Ada in software re/reverse engineering. There is no need of knowledge of the underlying OS for software understanding in this approach, since the dependency on the OS in the legacy software is removed. It is portable and interoperable on Ada run-time environments. This approach can handle the OS calls in different legacy software systems.

  • PDF

Explanatory Correction Notes for Lowell's Chosön Photographs in the Boston Museum of Fine Art (미국 보스턴미술관 소재 로웰의 조선 사진 설명문의 오류와 정정 방안)

  • Jeong, Youngjin
    • Korean Journal of Heritage: History & Science
    • /
    • v.53 no.2
    • /
    • pp.36-63
    • /
    • 2020
  • Percival Lowell took photographs of 80s during his stay in Korea in the winter of 1883 and 1884. The photographs are the first in the history of Korea and contain various and precious information about Korea of the day. As such, they could be used for purposes of studying late 19th century Chosōn society. The 61 photographs that are archived in Boston Museum of Fine Art were catalogued by National Research Institute of Cultural Heritage and have been posted online with incorrect explanations by Boston Museum of Fine Art. The explanations have been composed and revised at least four times on the basis of Lowell's writings and archivists' understandings of Korea. However these explanations contain many errors regarding the content of the photographs, yet have been cited by researchers and books concerning the history of Korea. I examined the explanations, analyzed Lowell's writings and diplomatic documents, and confirmed the locations where the photographs were taken. Accordingly, I suggest improved explanations of the photographs to prevent misuse of the Boston Museum of Fine Art's online archive. Lowell's photographs of Chosōn have very high historical value and could be used in various cultural fields because of their various contents and high definition. However, they belong to America and are not cared for sufficiently. Therefore, I suggest that high definition digital scans and prints of the photographs be generated for the sake of overseas Korean cultural heritage collection.

Awareness and Consciousness Survey of Worker's for Radiation Exposure Dose Reduction from Pediatric Brain CT Examination (소아두부 컴퓨터단층촬영검사에서 방사선피폭선량 저감화를 위한 근무자의 인식도와 의식도 조사)

  • Kim, Hyeon-Jin;Lee, Hyo-Yeong;Im, In-Chul;Yu, Yun-Sik
    • Journal of the Korean Society of Radiology
    • /
    • v.10 no.3
    • /
    • pp.207-214
    • /
    • 2016
  • In this study, it was an investigation of the degree of awareness and consciousness of the radiology technicians about radiation protection working in the computed tomography room in Busan when the pediatric underwent brain CT scan. It was sorted by university hospital, general hospital and hospital and compared the scores of awareness and consciousness. As a result of awareness, university hospital had the highest point of 42.29 followed by general hospital and hospital of 38.43 and 34.06 respectively. On the other hand, the average score of consciousness was the highest in hospital of 29.19 followed by general hospital and university hospital of 24.68 and 21.37 respectively. It is considered to need assistance to cultivate an awareness of the radiation through refresher training and conferences, etc in order to increase the awareness of the general hospitals and hospitals for CT workers. In addition, it is also expected to pay for efforts to increase the consciousness of CT workers in university hospitals seeking the optimization of radiation protection and dose reduction of radiation exposure for the pediatric.

G/T Experts' Recognition on Educating ICT Core-competencies for Gifted Students in Science (과학영재를 위한 ICT 핵심역량 교육에 대한 전문가 인식 조사)

  • Lee, Jaeho;Jin, Sukun;Shin, Hyunkyung
    • Journal of Internet Computing and Services
    • /
    • v.17 no.6
    • /
    • pp.143-152
    • /
    • 2016
  • In this paper, we attempted to provide the bases of effective educational programs for fostering ICT competencies of gifted students in science. For this purpose, we tried to answer the questions like 'What are the ICT core-competence for gifted students in science?' and 'How can we educate those competencies effectively?' We started by reviewing existing studies on ICT competencies for talented people in future society and then adopted one[6] as the basis for further validation. We tried to work with as many G/T experts as possible, and decided to use the online survey methodology because the experts are scattered all over the country. The survey was sent to the corresponding person who is in charge of G/T education in each area, and then e-mailed to G/T experts in that area. Through these procedures, three hundred four(304) G/T experts from all around the country participated in this survey. The results showed the followings: (1) G/T experts agreed with the importance and necessity of ICT competencies for gifted students in science; (2) G/T experts agreed with the validity of three core ICT competencies, which are 'knowledge and skills competence, creativity competence, and characteristic competence,' for gifted students in science; (3) G/T experts agreed with the validity of educational goals, which are suggested for fostering each ICT core-competence of gifted students in science; and (4) G/T experts regarded 'product-oriented education' and 'ICT device-oriented education' as important and effective types of education programs for fostering ICT competencies of gifted students in science.

Vegetation Status and Characteristics of the Spatial Distribution in Taeanhaean National Park (태안해안국립공원 식생 현황과 공간분포 특성)

  • Lee, Seon-Mi;Myeong, Hyeon-Ho
    • Korean Journal of Ecology and Environment
    • /
    • v.48 no.2
    • /
    • pp.122-128
    • /
    • 2015
  • This study aims to figure out the vegetation status and characteristics of the spatial distribution in Taeanhaean National Park. As a result, vegetation communities were Pinus thunbergii community, Pinus densiflora community, Pinus thunbergii-Pinus densiflora community, Camellia japonica community, Carpinus turczaninowii community, Carpinus turczaninowii-Pinus thunbergii community, Kalopanax septemlobus community, Koelreuteria paniculata community, Robinia pseudoacacia community, and sand dune and coastal wetland vegetation including Vitex rotundifolia community, Elymus mollis community, Calamagrostis epigeios community, Ischaemum anthephoroides community, Zoysia sinica community, Suaeda maritima community, and Phragmites communis community. Landscape types in actual vegetation map were Pinus thunbergii community (3.92%), Pinus densiflora community (1.40%), Robinia pseudoacacia community (0.05%), sand dune and coastal wetland vegetation (0.11%), field (0.46%), seashore (0.24%), thinning area (0.08%), bareground (0.16%), and sea (93.58%). Area of Pinus thunbergii community among vegetation type was $14.797km^2$ (3.92%) and the largest. Stratification structure and species composition of Pinus thunbergii community distributed in the seashore were different as a result of disturbance and human use. On the other hand, we assumed that succession will take place to the potential natural vegetation that is Quercus serrata and Quercus dentata in undisturbed Pinus thunbergii community. Meanwhile, Erechtites hieracifolia was occupied in understory of Pinus thunbergii community around the seashore and Diodia teres was invaded to sand dune vegetation. They may affect on natural species negatively. Therefore, monitoring and management plans are necessary.

A Database of Simple Sequence Repeat (SSR) Marker-Based DNA Profiles of Citrus and Related Cultivars and Germplasm (SSR Marker를 이용한 감귤속 품종 및 유전자원에 대한 DNA Profile Data Base 구축)

  • Hong, Jee-Hwa;Chae, Chi-Won;Choi, Keun-Jin;Kwon, Yong-Sham
    • Horticultural Science & Technology
    • /
    • v.34 no.1
    • /
    • pp.142-153
    • /
    • 2016
  • The present study investigated identification of cultivars through phylogenetic analysis of 108 Citrus varieties and related cultivars using simple sequence repeat (SSR) markers. Two hundred three SSR primer pairs were used to detect polymorphic markers among 8 Citrus cultivars consisting of 4 mandarins, 1 orange, 1 tangor, 1 tangelo, and 1 pumelo. Eighteen SSR primer pairs were reproducible and showed highly polymorphic alleles. These markers were applied to assess genetic variations of the 108 varieties. Each marker detected 5-14 alleles, with an average of 9.28. The polymorphism information content varied from 0.417 to 0.791 with an average of 0.706. Cluster analysis with SSR markers resulted in 13 major groups reflecting cultivar types and pedigree information. Twelve orange cultivars in the $I-1^{st}$ sub-cluster and 23 mandarin cultivars in the $II-1^{st}$ sub-cluster, respectively, were not discriminated using the SSR markers. This could be due to narrow genetic backgrounds originated through bud mutation or nucellars seedlings. The SSR profile database of Citrus cultivars will be useful as a tool for protection of plant breeders' intellectual property rights in addition to assessing genetic diversity in Citrus cultivars and germplasms.

청주지역 주부들의 수입식품 이용실태 및 분별능력

  • 김기남;박은진;손은미
    • Proceedings of the KSCN Conference
    • /
    • 2003.11a
    • /
    • pp.1074-1075
    • /
    • 2003
  • WTO 출범 이후 우리나라 국민의 식생활 중 수입식품이 차지하는 비중이 급속히 늘어나면서 수입식품 자체의 위해성과 수입농산물에 관한 지식이나 정보가 소비자들에게 부족하여 올바른 구입과 소비가 어렵게 되어 피해를 당하는 경우도 발생하고 있다. 본 연구에서는 청주지역 주부들을 대상으로 수입식품 이용과 인식도 및 수입식품 분별능력의 조사를 통하여, 교육의 필요성여부를 검토하였다. 조사 대상자는 청주시에 거주하는 주부 183명이었고, 조사기간은 2003년 3월 1일부터 3월 15일까지였다. 조사내용은 조사대상자의 일반사항, 식품구입시 태도, 수입식품 구입 경험, 수입식품에 대한 인식도, 수입식품과 국산식품의 분별력 테스트로 구성되었으며, 인식도는 5점 척도에 의해 조사되었다. 사용된 통계처리 방법은 SAS program을 사용하여 빈도, 백분율, 평균, 표준편차를 구하였고, Chi-square 또는 ANOVA로 검정하였다. 연구결과는 다음과 같다. 국내산과 수입산 표시의 확인여부는 응답자의 92.3%가 확인한다고 응답하였고, 선호도를 조사한 결과 99.5%가 국내산을 선호하는 것으로 나타났다. 선호하는 주된 이유로는 ‘수입산은 유해물질이 많으므로’라는 응답이 46.3%로 가장 많이 나타났고, 수입식품 구입경험의 유무로는 92.3%가 경험이 있다고 응답하였으며, 구입동기에 대해 ‘수입산이 시중에 많아 쉽게 구입할 수 있기 때문에’라는 응답이 61.6%로 가장 많았다. 또한 수입식품을 국산식품으로 혼동하여 구입한 경험으로는 응답자의 76%가 ‘있다’고 응답하였으며 혼동한 이유로는 ‘수입식품과 국산식품의 구분이 명확하지 않아서’ 49.6%, ‘수입산과 국내산의 표시가 명확하지 않아서’ 41%를 차지했다. 국내산과 수입산 표시에 대한 신뢰도는 89.7%가 대체로 신뢰하지 않는 것으로 나타났다. 신뢰하지 않는 이유로는 ‘허위표시에 대한 보도를 많이 접해서’가 56.l%로 가장 많은 비율을 차지했다. 수입식품의 인식도를 품질, 가격, 포장 용기, 맛, 조리편리성, 안전성, 건강에 미치는 영향의 7가지 측면에서 살펴보았는데, 수입식품의 품질과 맛에서 국내산과 비슷하거나 나쁘다고 인지하였고, 가격은 수입식품이 싸다고 인지하고 있었으며 연령과 유의성을 보였다(p <0.01). 포장 용기와 조리편리성에 대해서는 국내산과 비슷하거나 좋다고 인지하고 있었으며, 조리편리성은 학력과 유의성이 높게 나타났다(p < 0.01). 안전성과 건강에 미치는 영향에 대해서는 나쁘다고 인지하고 있었다. 수입식품과 국산식품의 분별정도는 66.1%가 구별하는 능력이 언다고 응답하였다. 분별정보를 얻는 경로로는 ‘TV 및 라디오 프로그램’이 61.7%로 가장 많았다. 수입식품에 관한 교육을 받을 의향에 있어서 61.5%가 ‘예’라고 응답하였고, 필요한 교육에 대해 ‘국산식품과 수입식품의 분별법에 관한 내용’이 75.4%로 가장 많았다. 수입식품 분별력 테스트에 있어서는 40점 만점에 평균이 13.6 $\pm$ 7.4점으로 낮았고, 분별력이 가장 좋은 품목은 고사리(53.6%), 분별력이 가장 낮은 품목은 고춧가루(40.4%)로 나타났다. 분별정도에 있어서 ‘매우 잘 구별한다’고 응답한 사람일수록 분별력 점수가 높게 나타나 주부들이 자신의 분별능력에 대해 매우 잘 인지하고 있다는 것을 알 수 있었다(p<0.001). 이상의 결과를 통하여 대부분의 응답자가 수입산에 대해 부정적인 태도를 보이고 있으나 대부분 구입경험이 있고, 분별력 점수도 낮은 편이었다. 따라서 국내 소비자들의 피해를 줄이기 위하여는 수입식품과 국내식품의 특징 및 분별법에 대한 대중매체를 통한 홍보와 이에 대한 교육의 기회가 확대되어져야 하겠다.

  • PDF

A Study on Differences of Aesthetic Experience in the Exhibition of Artworks and the Remediated Exhibition of Artworks: A Comparative Study between and (예술작품의 원작으로 구성된 전시와 원작을 재매개한 디지털 전시의 미적 경험에 대한 상이성 연구: <모네,빛을 그리다전(展)>와 <풍경으로 보는 인상주의전(展)>의 비교연구)

  • Rhee, Boa;Choi, Sumin;Hong, Yong Seok
    • The Journal of the Korea Contents Association
    • /
    • v.17 no.5
    • /
    • pp.153-164
    • /
    • 2017
  • This research concurrently conducts literature review and quantitative research methodology in order to compare aesthetic experience of and . From the perspective of viewing attitudes, two types of perception equally coexist in both exhibitions: convergent perception is predominant over distracted perception in IL while distracted perception is higher than convergent perception in MIE. However, the influence of convergent perception on the degree of satisfaction and immersion is proved only in MIE. In terms of roles of viewer, there is a tendency to weigh on passive role in both exhibitions. In particular, it is worth noting that the role is relatively high in MIE. The role of viewer do not correlate with on the degree of satisfaction and immersion, as well as modes of perception. The elements of aesthetic experience are highly rated and the use of previous knowledge acts as a positive influence on the role of viewers in IL. Through this study, we witness the fact that visitors who are familiar with traditional artworks depend upon both modes of perception as well as passive role of viewer in the digital exhibition. In conclusion, remediation through digital technology has blurred the boundary of the dichotomy of a viewing attitude and a role of viewer depending on exhibit media, consequently MIE bears both natures of traditional artworks and digital media.

A Study on Analysis of Factors Affecting Technology Transfer Performance of Universities : An Approach to Different Types of Korean Universities (대학의 기술이전성과 영향요인 분석 : 대학의 유형별 접근)

  • Lee, Chang-Hak;Lee, Cheol-Gyu;Lee, Dong-Myung
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.12 no.9
    • /
    • pp.3936-3951
    • /
    • 2011
  • This paper aims to analyze factors affecting technology transfer performance according to different types of Korean universities and to conduct the research for the channel and extent of impact between these factors, utilizing 5 - year data for the technology transfers of 110 universities based on the survey by National Research Foundation of Korea. According to the analysis, incentive for researchers is the most crucial factor in local universities and small & medium-sized private universities located in the capital area. And numerical value of intellectual property rights owned by university is the key factor in universities specializing in science & engineering / industry. Also, Big-sized universities are heavily affected by the number of full-time faculty. In case of private universities, government subsidy relating to patents is critical factor for technology transfer performance. The mean value of all variables is a lot higher in participant universities than non-participant ones in CK(Connect Korea) project. In summary, it is suggested that steady financial support provided by the government is required and that mutual cooperation for industry-university-government is also needed for the commercialization of the technologies held by universities.