Carbon Black이 시멘트 Paste 및 Mortar의 물리적 특성에 미치는 영향

홍원표,황의환,조헌영 忠南大學校 産業技術硏究所 1986 산업기술연구논문집 Vol.1 No.2

This study was performed to determine the most desirable carbon black and it's content in ordinary porland cement for the increase of physical properties of the cement and mortar. The various contents of carbon black were used for this study such as 0.2wt%, 0.5wt%, 1.0wt% and 3.0wt%. The different particle size and structure of carbon black were used. The physical properties of the cement paste and mortar were tested by KS methods. The experimental results are as follow; 1) The contents of 0.5-1.0wt% carbon blacks in cement increased most apparently the setting time of cement paste, flow value, compressive and flexural strengths of mortar, whereas decreased the water absorption ratio of mortar by about 10%. 2) SNP and D company's carbon black which have smaller numbers of I₂adsorption and DBP absorption and heavier pour density than those of others showed to be the most effective carbon blacks. 3) The soundness of cements remained unchanged regardless to the different kinds and contents of carbon blacks.

Pyridine 촉매하의 Cyclohexene의 Ozonolysis

홍원표,양현수,장자순,김철규 忠南大學校 産業技術硏究所 1988 산업기술연구논문집 Vol.3 No.2

Terminally functionalized molecules are essential building block for the formation of polymers by polycondensation reactions. It is the major goal of this research to establish new routes for the preparation of such molecules by selective oxidation reaction of cyclohexene, using ozone as an oxydizing agent. To this purpose, it has been explored, whether the usual course of the ozonolysis of olefins can be modified with the help of specific catalyst in order to introduce the desired functional groups. In particular, the ozonolysis of cyclohexene in hydrocarbon solvents and in the presence of pyridine has been tested with the goal of preparing molecules containing one aldehyde and one carboxylic acid group. Ozonolysis of cyclohexene in hydrocarbon solvents such as methylene chloride and pentane can be guided by catalysis with pyridine, such that the reactions afford desired molecules. In this manner, pyridine catalized ozone oxidation converted cyclohexene into the corresponding 6-oxohexanoic acid(45.87%), adipaldehyde(14.68%), and polymeric ozonide(39.45%), via the ω-formyl carbonyl oxides in CH₂Cl₂at 0℃.

RMR등급에 따른 NATM터널 지보형식 설계

홍원표,장귀환 중앙대학교 기술과학연구소 1999 기술과학연구소 논문집 Vol.29 No.-

서울시 지하철의 NATM 터널 설계에 사용되고 있는 터널지보형식은 암의 단순한 분류에 의거하여 결정되고 있다. 이렇게 결정된 터널지보형식은 RMR분류에 의거하여 결정되는 터널지보형식에 비하여 비경제적이다. 따라서, 본 연구에서는 서울시 지하철 구간중 RMR등급에 의해 분류될 수 있는 3개의 사례현장을 대상으로 지하철 표준지보단면과 RMR등급에 따른 지보단면의 해석결과를 비교검토한다. 또한, 해석결과로부터 NATM터널 설계에 적용될 수 있는 탄성계수의 적정치가 검토된다. On design of NATM tunnels for subway in Seoul, the support system for tunnels is usually decided on the basis of simple rock classification. The support system based on the simple rock classification is more conservative than the support system decided on the basis of RMR classification. In this study, a comparison of analysis for three field cases of subway in Seoul is performed for both the conventional support system and the support system based on the RMR classification. Also, the suitable elastic modulus on design of NATM tunnels is investigated from the analytical results.

리비아 대수로공사 지역의 지반특성

홍원표,남정만,김시현,이재호 중앙대학교 기술과학연구소 1996 기술과학연구소 논문집 Vol.26 No.-

리비아 사막지역의 지반특성을 연구하기 위하여 리비아 1단계 대수로공사가 실시된 지역의 지반특성을 검토하였다. 본 연구에서는 Sarir 취수원에서 Ajdabiya 저수조를 경유하여 Sirt 저수조까지의 대수로 공사지역을 따라 실시된 실내시험과 현장시험결과를 포함하고 있다. 이 지역은 내륙지역(Sarir 취수원에서 Ajdabiya 저수조까지)과 해안지역(Ajdabiya 저수조에서 Sirt 저수조까지)으로 구분하여 연구된다. 본 연구결과, 지표면 부근에 있는 모암(Cap rock)은 주로 Caliche나 석회사암(Calcarenite) 성분을 많이 띠고 있고, 이들의 깊이에 따른 강도변화는 발견할 수 없었다. 또한 모래에 대한 Ncl도 깊이에 대한 변화를 발견할 수 없었으나 이들을 종류별로 분류하였을 경우, N치가 약간 증가하는 추세를 보였다. 끝으로 해안지역의 점토에서는 지표면부근에서 조금 과압밀된 경향을 볼 수 있었으며, 내륙지역의 점토에서는 대단히 높은 팽윤포텐셜이 관찰되었다. To study geotechnical properties on Sahara desert of Libya, geotechnical characteristics in the region of the Great Man-made River Project were reviewed. A series of field and laboratory tests were carried out along the route of the conveyance lines from Sarir well field to Sirt end reservoir through Ajdabiya holding reservoir. In the view of geotechnical aspect, the research subject area can be divided into two areas ; one is the inland area(from Ajdabiya holding reservoir to Sirt reservoir). The results of this study showed that the cap rocks nearby ground surface were generally composed of caliche or calcarenite and variation of its strength according to depth could not find. Also, N value in sand did not show a trend of variation with depth however, the N value in the classified soil reveals tendency to increased. The clay of ground surface in the coastal area was slightly overconsolidated due to the desiccation of the surface soils. The clay in the inland area had high swelling potential.

韓國의 암발파 진동상수에 관한 연구

홍원표,엄영진,윤중만 중앙대학교 기술과학연구소 1995 기술과학연구소 논문집 Vol.25 No.-

암반지반에서 절토나 지하굴착을 실시할 때 암발파로 인해 진동과 소음이 발생하게 된다. 지반진동은 인접구조물에 손상을 주거나 인근주민에게 불쾌감을 주기 때문에 지반진동의 발생기구나 인접구조물에 영향을 미치는 매카니즘을 정확히 예측하는 것은 매우 중요하다. 따라서 본 연구의 목적은 지반진동에 대한 규준을 마련하는데 있다. 지반진동은 최대입자속도, 발파에너지, 진동원으로 부터의 거리에 영향을 받는 것으로 나타났다. 또한, 본 연구에서 산정된 진동식의 최대입자속도는 기존의 제안식보다 약간 작게 나타나고 있으나 진동원으로부터 50~100m 이내의 거리에서는 매우 유사하게 나타나고 있다. Vibration and noises are occured dut to rock blasting work for cutting and underground excavation performed in rock ground. It is very important to control the vibration produced according to rock blasting. Therefore, the main objective of this paper is to estabilish criteria of vibration to control blasting. Vibration is influnced by peck particle velocity, blasting energy, distance from vibration source and strength of rock. The peck particle velocities estimated by the vibration equations presented in this paper are lower than those estimated by existing empirical equations but both show very similar within distance from 50m to 100m.

전력계통에서의 초전도전력기기의 제어 및 운전

홍원표 大田産業大學校 1996 한밭대학교 논문집 Vol.13 No.0201

An image of future power system which has introduced superconducting generator, cable, transformer, fault current limiter, SMES and so on is presented. Conceptual designs of each SC Machines and devices are carried out. The SC cable and SFCL utilize the high Tc superconductor(HTS) cooled by liquid N_2-. Other devices use low temperature superconducting cooled by liquid He. The SC power system models are proposed detailedly. In viewpoint of the operation and control SC power system, the concrete design direction and effective role of each SC apparatus are investigated. In this paper, superconducting fault limiters(SFCLS) should play an important part of the quenching current level coordination to prevent the other SC devices from quenching. Finially, SFCL are also expected to be very effective to introduce flexibility of power system planning and operation due to their possibility to enhance transient stability and reduce short circuit current.

초전도고장전류제한기가 포함된 전력시스템에서 고장전류계산방법과 고장전류억제효과 분석

홍원표 大田産業大學校 1998 한밭대학교 논문집 Vol.15 No.1

Design & Operation of power system for meeting increase of electric power demand is becoming more difficult and complex. One of reasons is increase of fault current. As one of the most effective methods for suppressing the fault current, installation of SFCL is expected. This paper describes a method of fault analyses of power system with SFCLs, and also discusses determination of specification two-bus electric power system with single transmission lines

진공용 나노스테이지 개발

홍원표,강은구,이석우,최헌종 한국공작기계학회 2004 한국공작기계학회 춘계학술대회논문집 Vol.2004 No.-

Miniaturization is the central theme in modem fabrication technology. Many of the components used in modern products are becoming smaller and smaller. The direct write FIB technology has several advantages over contemporary micromachining technology, including better feature resolution with low lateral scattering and capability of maskless fabrication. Therefore, the application of focused ion beam(FIB) technology in micro fabricaton has beome increasingly popular. In recent model of FIB, however the feeding system has been a very coarse resolution of about a few μm. It is not unsuitable to the sputtering and the deposition to make the high-precision structure in micro or macro scale. Our research is the development of nano stage of 200mm strokes and 10nm resolutions. Also, this stage should be effectively operating in ultra high vacuum of about 1×10^(-5)pa. This paper presents the concept of nano stages and the discussion of the material treatment for ultra high vacuum.

NATM 통신구터널 지보패턴에 관한 연구

홍원표,한중근,이상곤 중앙대학교 기술과학연구소 1998 기술과학연구소 논문집 Vol.28 No.-

우리나라에서 NATM 통신구터널에 적용되고 있는 암반분류형태 및 지보패턴은 지하철 도시터널과 같이 대형단면 터널에 적용되는 기준을 그대로 적용하고 있는 실정이다. 그러나 NATM 통신구터널은 대개 소형단면터널이며 깊은 tal도에서 시공되는 것이 일반적이다. 따라서 NATM 통신구터널의 설계 및 시공시에는 적절한 지반암반의 정량화 및 공학적 분류법을 별도로 마련하여 이 분류에 근거한 적합한 지보모델을 제시할 필요가 있다. 본 연구에서는 NATM 통신터널에 적합한 표준지보패턴과 암반분류모델을 7등급으로 구분 제시하며 제시된 암반 분류등급별 지보패턴에 대한 합리성이 터널시공사례에 대한 유한차분해석을 통해 검증된다. The classification of rock-mass and its reinforcement pattern used for Communication Cable Vault in Korea have been actually used such methods that applied to largesectional tunnel construction such as Subway urban-tunneling. However, in the case of small sized tunnel works for Communication Cable Vault which are generally adopted at deep depth, the proper reinforcing support model should be suggested on the basis of quantitative classification of rock-mass for design and construction. This paper presented standard reinforcement pattern and classification model of rock-mass for NATM of Communication Cable Vault. They are divided in to 7-categories of grades and reasonability of these suggestion is ascertained from numerical analysis for the construction of these suggestion is ascertained from numerical analysis for the construction of Tunnel.

Stator Current Processing –Based Technique for Bearing Damage Detection in Induction Motors

Won ?Pyo Hong,Chung-Sup Yoon,Dong-Hwa Kim 제어로봇시스템학회 2005 제어로봇시스템학회 국제학술대회 논문집 Vol.2005 No.6