• Title/Summary/Keyword: Byung-cheon Park

Search Result 165, Processing Time 0.025 seconds

Possibility for Reduction in Autogenous Shrinkage of High Strength Mortar due to Plant Oils (식물성유지류에 의한 고강도 모르터의 자기수축 저감 가능성 검토)

  • Song, Ri-Fan;Park, Byung-Kwan;Ba다, Dae-Hyun;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2009.05a
    • /
    • pp.313-314
    • /
    • 2009
  • With the purpose of reducing autogenous shrinkage of high strength mortar, shrinkage reduction effect was examined in this study using plant oils as the compound for shrinkage reduction. As a result of examination, satisfactory reduction effect was shown using plant oils in comparison to plain mixture. Most excellent effect was shown by soybean oil.

  • PDF

The Characteristics of Energy Consumption with Operational Conditions for the Central Cooling System (냉방시스템의 운전조건에 따른 에너지 소비특성 연구)

  • Park, Gi-Tae;Ahn, Byung-Cheon
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
    • /
    • v.15 no.4
    • /
    • pp.39-45
    • /
    • 2019
  • The operational conditions such as cooling tower water pump flow rate, cooling tower fan flow rate, and chiller capacity in heat source equipment, and supply air temperature and chilled water temperature in air conditioner are considered to study the effects on energy consumption for central cooling system by using TRNSYS program. As a result, the optimal values of supply air temperature and chilled water temperature for minimal total energy consumption are 12℃ and 8℃. And if maximum values of cooling tower water pump and fan flow rate is decreased from 100% to 40%, energy consumptions are increased 170MJ/day and 63.2MJ/day, respectively.

Analysis Strength Improvement on 50 to 80 MPa Level High Performance Concrete (50~80 MPa급 고성능 콘크리트의 강도증진해석)

  • Park, Byung-Kwan;Lee, Ju-Sun;Jang, Ki-Hyun;Choi, Young-Wha;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2008.11a
    • /
    • pp.93-96
    • /
    • 2008
  • This research performed strength improvement analysis after evaluating strength characteristics by estimated temperatures to evaluate the real time strength performance of 50 to 80 MPa high performance concrete equipped with heat resistance, and the results are as follows. The lesser W/B and the lesser target slump flow value difference, compression strength was shown to increase, and the more curing temperature becomes, the strength increased accordingly. According to the correlation review result of strength improvement analysis by estimated temperature change performed using logistic analysis model, the compression strength value predicted with logistic curve expression and the compression strength value measured in experiment were shown to have similar correlation, and the strength improvement analysis value by logistic model was shown to be estimated good when W/B is high.

  • PDF

Analysis of the Flowability for Organic·Inorganic Fiber with the Variation of Length (유·무기 섬유 길이조합변화에 따른 섬유 보강 모르타르의 유동성 분석)

  • Park, Yong-Jun;Kang, Byung-Hoi;Lee, Hong-Kyu;Jo, Man-Ki;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2014.05a
    • /
    • pp.128-129
    • /
    • 2014
  • In this study, flowability of the mortar added with length change and combination of steel and inorganic fiber has been tested to evaluate the performance of fiber-reinforced mortar. The following results could be made as the conclusion. Early age flow of the mortar has been decreased when fibers added. Slump also decreased with the adding of fibers. For the air content, comparing with Plain, all the specimens with fibers showed higher air content than Plain., Addition of every kinds fibers showed the similar EIS test results.

  • PDF

Pentacene OTFTs with $Al_2O_3$ gate insulator by Atomic Layer Deposition Process

  • Jin, Sung-Hun;Kim, Jin-Wook;Lee, Cheon-An;Park, Byung-Gook;Lee, Jong-Duk
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2003.07a
    • /
    • pp.15-18
    • /
    • 2003
  • Pentacene OTFTs of $Al_2O_3$ insulator treated with a diluted PMMA were fabricated for the application of the low voltage operation and large area displays. The operation voltage of 15 V and the mobility of 0.35 $cm^2/Vsec$ are obtained even adopting the thick dielectric of 100 nm which was deposited by atomic layer deposition at the temperature of $150^{\circ}C$. The current on-off ratio was $4.1{\times}10^4$ for the OTFTs treated with 9:1 PMMA and good saturation characteristics were obtained as drain voltage increases.

  • PDF

Synthesis and Structure-Activity Relationship Studies of Substituted Isoquinoline Analogs Antitumor Agent

  • Cheon, Seung-Hoon;Park, Joon-Suck;Chung, Byung-Ho;Choi, Bo-Gil;Cho, Won-Jae;Choi, Sang-Un;Lee, Chong-Ock
    • Archives of Pharmacal Research
    • /
    • v.21 no.2
    • /
    • pp.193-197
    • /
    • 1998
  • A number of substituted isoquinolin-1-ones, possible bioisosteres of the 5-aryl substituted 2,3-dihydroimidazo[2,$1-a$]isoquinolines, were synthesized and tested for their antitumor activity against five different human tumor cell lines. O-(3-hydroxyporpyl) substituted compound (15) exhibited the best antitumor activity which is 3-5 times better than 5-[$4^1$-(piperidinomethyl)phenyl]-2,3-dihydroimidazo[2,$1-a$]isoquinoline (1).

  • PDF

A Study on the Properties of Quality of Concrete Using Mixed Sand Improved Grading (개량입도 혼합모래를 사용한 콘크리트의 품질특성에 관한 연구)

  • Kim Ki-Hoon;Han Min-Cheoi;Park Koo-Byung;Yoon Gi-Won;Han Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • v.y2004m10
    • /
    • pp.55-58
    • /
    • 2004
  • This paper investigated the results of quality of concrete using mixed sand with grading adjustment in order to find out the applicability of fine aggregate with bad grading, According to test results, fluidity of concrete with fine level grading river sand was decreased while with coarse level grading crushed sand increased compared with that with medium level grading crushed sand. Use of mixed sand with grading adjustment(MSG) resulted in an improvement in fluidity. Increase in fineness modulus led to an increase in bleeding, For compressive strength, use of MSG increased compressive strength. For drying shrinkage, use of fine level grading river sand resulted in an increasing drying shrinkage due to the larger presence of fine particles, while use of MSG led to a reduction in drying shrinkage

  • PDF

Hangul Text Detection using Text Corner Edge Feature Analysis in Natural Scene Images (자연영상에서 코너 에지 특징 분석방법을 이용한 한글 텍스트 검출기법에 관한 연구)

  • Park Jong-Cheon;Kwon Kyo-Hyun;Jun Byung-Min
    • Proceedings of the Korea Contents Association Conference
    • /
    • 2005.11a
    • /
    • pp.379-383
    • /
    • 2005
  • 본 연구에서는 자연 이미지에서 한글 텍스트가 갖고 있는 에지 코너 특징을 이용한 한글 텍스트 검출방법을 제안한다. 자연영상으로부터 에지를 검출하고, 검출된 에지를 20종류의 에지 구조 성분을 갖는 에지 맵을 생성한다. 생성된 에지 맵에서 한글 텍스트 특징 갖는 특징들을 조합하여 모두 8가지의 텍스트 영역 후보 특징을 추출한다. 추출된 텍스트 영역의 특징을 수평 및 수직방향으로 검사하여 텍스트의 시작 라인과 끝라인을 검출하여 텍스트 영역의 수평좌표를 구한다. 추출된 텍스트 후보 영역에서 최종적으로 텍스트 영역을 결정한다. 제안한 방법은 다양한 종류의 자연 이미지에서 텍스트 영역을 검출에서 좋은 성능을 나타냈다.

  • PDF

A Study on the Marine Survey Characteristics in Incheon.Jindo Coastal Area (인천.진도 연안해역 해양특성조사 연구)

  • Yoon, Ha-Su;Choi, Yun-Soo;Lee, Sang-Jin;Chang, Eun-Mi;Park, Byung-Moon
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2010.04a
    • /
    • pp.137-138
    • /
    • 2010
  • On this paper, it's investigating about the coastal area of In-Cheon, northern Jin-Do, and therefore it's aimed to modernize the surveying information, which was made by the old equipments, and establish the total information infrastructure by collecting the basic information of national coastal area for the marine policy, and create the new growth engine from managing the national coastal information.

  • PDF

Min-Max Regret Version of an m-Machine Ordered Flow Shop with Uncertain Processing Times

  • Park, Myoung-Ju;Choi, Byung-Cheon
    • Management Science and Financial Engineering
    • /
    • v.21 no.1
    • /
    • pp.1-9
    • /
    • 2015
  • We consider an m-machine flow shop scheduling problem to minimize the latest completion time, where processing times are uncertain. Processing time uncertainty is described through a finite set of processing time vectors. The objective is to minimize maximum deviation from optimality for all scenarios. Since this problem is known to be NP-hard, we consider it with an ordered property. We discuss optimality properties and develop a pseudo-polynomial time approach for the problem with a fixed number of machines and scenarios. Furthermore, we find two special structures for processing time uncertainty that keep the problem NP-hard, even for two machines and two scenarios. Finally, we investigate a special structure for uncertain processing times that makes the problem polynomially solvable.