1,726,051 research outputs found
Jin-Yong Yang
No full text학위논문(석사)--아주대학교 공학대학원 :에너지학과,2019. 21년 365일 쇳물을 생산하는 제철소는 공정의 열을 제어하는 수처리 설비에 대향류 쿨링타워가 운영되고 있다.
대향류 쿨링타워 처리수온도 저감의 필요성은 처리수온도 설계·관리기준 35℃를 초과하고 36.3℃로 운전되고 있으며 처리수온도 상승으로 일부 온도하락용 보충수 공급으로 에너지 낭비가 발생하고 있다.
그리하여 쿨링타워의 작동원리, 운영현황, 공정별 처리수온도 현황 등을 파악하고 이론적 검토를 통해 처리수온도와 관계가 있을 것으로 예상되는 유입수열량, 유입공기열량, 배출공기열량, 그리고 설비고장에 따른 영향, 이 4가지 특성에 관하여 분석한다.
분석결과는
첫째 처리수온도와 유입수열량은 90.2% 상관관계분석
둘째 처리수온도는 30.39×0.05460 유입공기열량으로 관계 분석
셋째 처리수온도와 배출공기열량은 83.5%의 상관관계분석
넷째 설비고장에 따른 관계분석으로 실험을 통해 정상운전과 설비고장시 온도비교 하여 등분산검정 및 평균차 검정결과 관계가 있음 확인
또한 설비고장건수를 단계적으로 유형별 파레토도를 분석하여 감속기 진동·윤활문제가 전체의 89.7%로 분석되었다.
쿨링타워 처리수온도 저감 대책은
QC기법을 활용하여 4가지 특성인자에 대해 각각 특성요인도를 작성하고 원인 분석을 하여 주요요인을 정리하며 쿨링타워 처리수 감소의 목표를 설계·관리기준 35℃보다 1.8℃ 이하인 34.5℃로 설정하고 대책수립 계통도와 위험관리 분석 및 대책을 작성하였다.
쿨링타워 처리수온도 저감 개선은
첫째 배출공기열량증대(송풍기날개개수변경, 각도와 비산방지판 변경)
둘째 유입수열량감소(쿨링타워 배관 혼합 설치)
셋째 설비고장건수감소(감속기 베어링 하우징 재질, 밀봉장치 커버 구조변경)등으로 5개 테마로 개선하였다.
이러한 개선결과로 쿨링타워 처리수온도를 36.3℃에서 34.4℃로 1.9℃저감하였으며 배출공기열량증대 15.7%, 유입수열량감소 8.0%, 고장건수감소가 확인되었다.
유입공기열량은 외기온도 영향으로 습구온도 27.0℃(30℃, 80Rh%)에서 습구온도 30.0℃(32℃, 88Rh%)으로 쿨링타워 설계시 고려하여야 개선 될 것으로 파악 되었다.
결론으로 본 연구를 통해 쿨링타워 처리수온도 저감으로 년간 106,128㎥의 보충수의 에너지절감 효과를 달성하였다.Ⅰ. 서 론 1
1. 연구의 배경 및 목적 1
2. 연구의 방법 및 논문구성 3
2.1 연구 방법 3
2.2 논문 구성 4
Ⅱ. Cooling Tower 설비 운영 현황 분석 5
1. Cooling Tower System 5
1.1 Cooling Tower 설비 개요 6
1.2 Cooling Tower 설비의 분류 7
1.3. Cooling Tower 작동원리 12
2. 열연공장 Cooling Tower 운영 현황 13
2.1 열연공장 Cooling Tower 공정별 처리수온도 현황 14
3. Furnace Cooling Tower 처리수온도 관계 분석 16
3.1 처리수온도와 유입수열량 관계 분석 16
3.2 처리수온도와 유입공기열량 관계 분석 17
3.3 처리수온도와 배출공기열량 관계 분석 19
3.4 처리수온도와 설비고장에 따른 관계 분석 21
Ⅲ. Furnace Cooling Tower 처리수온도 저감 대책 25
1. 특성요인도 따른 원인 분석 25
2. 주요 요인 계통도에 따른 대책 27
2.1 주요 요인 계통도 27
2.2 대책 수립 계통도 28
3. 위험관리(Risk Management) 분석 및 대책 28
4. 처리수온도의 저감 대책 목표 설정 29
Ⅳ. Furnace Cooling Tower 처리수온도 저감 개선 30
1. Furnace Cooling Tower 배출공기열량 증대 30
1.1 Fan Blade 개수 변경 30
1.2 Fan Blade 각도 및 비산방지판 Type변경 32
2. Furnace Cooling Tower 유입수열량 감소 35
2.1 Cooling Tower 배관 Mixing Line 설치 35
3. Furnace Cooling Tower 고장건수 감소 39
3.1 감속기 Bearing Housing 재질 변경 39
3.2 감속기 Oil Seal Cover 구조 변경 42
Ⅴ. 결론 43
1. Furnace Cooling Tower 처리수온도 저감 개선 결과 43
2. 에너지절감 효과 및 향후전망 46
참고 문헌 50
ABSTRACT 51Maste
Going Beyond Counting First Authors in Author Co-citation Analysis
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only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
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Appropriate Similarity Measures for Author Cocitation Analysis
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Dispelling the Myths Behind First-author Citation Counts
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use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
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sj-pdf-1-jhs-10.1177_17531934231196438 - Supplemental material for Muscle redistribution technique for expressing motion intention in patients with wrist-level amputation
No full textSupplemental material, sj-pdf-1-jhs-10.1177_17531934231196438 for Muscle redistribution technique for expressing motion intention in patients with wrist-level amputation by Yong Yang, Qining Wang and Qipei Wei in Journal of Hand Surgery (European Volume)</p
Transkrip temubual Bersama Ρuan Fatimah Abdullah, tokoh dan penggiat seni Mak Yong yang terkenal dalam usaha melestarikan dan memartabatkan seni warisan bangsa
Full text linkMak Yong adalah satu genre seni Melayu yang penting. Aktiviti persembahannya pada awalnya menjadi seni di istana raja-raja Melayu, terutama pada zaman kegemilangannya, sebelum tersebar secara meluas di Kelantan, Terengganu, Kedah, dan juga Pahang. Kini, ia turut diangkat ke beberapa pusat pengajian tinggi di Malaysia. Mak Yong adalah teater tradisional Melayu yang penuh dengan ciri-ciri simbolik. Ciri-ciri persembahannya—seperti ritual, cerita, tarian, nyanyian, muzik, dan lakonan—kaya dengan unsur-unsur penambahbaikan (improvisasi), termasuk prop dan latar belakang yang mempunyai tujuan tertentu. Mak Yong juga merupakan seni teater yang mempunyai keunikan tersendiri. Pada tahun 2005, UNESCO mengiktiraf Mak Yong sebagai seni warisan negara Malaysia yang pertama dengan status "Warisan Budaya Tidak Ketara Dunia" (Intangible Cultural Heritage of Humanity). Oleh itu, dokumentasi sejarah lisan ini merupakan pengamatan secara langsung terhadap Mak Yong yang mengetengahkan Pn. Fatimah Abdullah sebagai tokoh Mak Yong yang terkenal dan perjuangan beliau sebagai peneraju Mak Yong Negara
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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