• 제목/요약/키워드: 상당조도

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A Study on Shear and Flexural Performance Evaluation of Circularly Corrugated Plate (원형 파형강판의 전단 및 휨 성능평가에 관한 연구 -전단 및 휨강도 설계식 제안-)

  • Moon, Seong Hwan;Oh, Sang Hoon
    • Journal of Korean Society of Steel Construction
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    • v.27 no.5
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    • pp.455-470
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    • 2015
  • This research suggest method to calculate more accurate shearing and bending force on corrugated steel plate that it is produced domestically. This research analyze limitation of former formula on domestic design standard and existing research. In addition The strength calculation formula on corrugated steel plate was proposed according to result of the experiment and FEM analysis. In this study, the result that compare experiment with analysis using the proposed shear buckling coefficient and limit width to thickness ratio indicate similar behavior. As the result of the research, It is judged that the structural member design and performance evaluation of the corrugated steel plate was conveniently applied.

The Influence of Corner Stress Singularities on the Vibration of Rhombic Plates Having Various Edge Conditions (다양한 연단조건을 갖는 마름모꼴형 평판의 진동에 대한 모서리 응력특이도의 영향)

  • Kim, Joo-Woo;Cheong, Myung-Chae
    • Journal of Korean Society of Steel Construction
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    • v.12 no.4 s.47
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    • pp.363-374
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    • 2000
  • An accurate method is presented for vibrations of rhombic plates having three different combinations of clamped, simply supported, and free edge conditions. A specific feature here is that the analysis explicitly considers the moment singularities that occur in the two opposite corners having obtuse angles of the rhombic plates. Stationary conditions of single-field Lagrangian functional are derived using the Ritz method. Convergence studies of frequencies show that the corner functions accelerate the convergence rate of solutions. In this paper, accurate frequencies and normalized contours of the vibratory transverse displacement are presented for highly skewed rhombic plates, so that a significant effect of corner stress singularities nay be understood.

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Graph Area Separation from A Sea Level Measurement Recording Image (조위관측기록 이미지로부터의 그래프 영역 분리)

  • Yu, Young-Jung;Park, Seong-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.1
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    • pp.175-182
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    • 2013
  • The digitalization of sea level measurement recording which is recorded as analog type is useful for many related oceanology. In this paper, we propose a method which separates the graph area from a sea level measurement recording image. At first, a pixel that is regarded as the pixel which is included in the graph area is selected. Then, many background pixels are separated using the color of the selected pixel. In each vertical line, a pixel is determined as the pixel within the graph area and the graph area is separated from the image using that pixels. Experimental results show that the proposed method in this paper overcome drawbacks of the previous research and can separate the graph area which similar to the graph area of the original image.

Efficient Similarity Joins by Adaptive Prefix Filtering (맞춤 접두 필터링을 이용한 효율적인 유사도 조인)

  • Park, Jong Soo
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.4
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    • pp.267-272
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    • 2013
  • As an important operation with many applications such as data cleaning and duplicate detection, the similarity join is a challenging issue, which finds all pairs of records whose similarities are above a given threshold in a dataset. We propose a new algorithm that uses the prefix filtering principle as strong constraints on generation of candidate pairs for fast similarity joins. The candidate pair is generated only when the current prefix token of a probing record shares one prefix token of an indexing record within the constrained prefix tokens by the principle. This generation method needs not to compute an upper bound of the overlap between two records, which results in reduction of execution time. Experimental results show that our algorithm significantly outperforms the previous prefix filtering-based algorithms on real datasets.

Dehydration Reaction of Phosphogypsum in a Fluidized Bed Reactor (유동화 반응조에서의 인산석고의 탈수반응에 관한 연구)

  • Il Hyun Park;Shin Hwan Ihn;Youn Soo Sohn
    • Journal of the Korean Chemical Society
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    • v.24 no.4
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    • pp.329-336
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    • 1980
  • A domestic phosphogypsum was calcined in a batch type fluidized bed reactor at various reaction temperatures ranging 90∼180$^{\circ}$ without and with an alkaline additive amounting up to 5% of gypsum, and physical properties of the resultant products were compared following their characterization by X-ray diffraction pattern and DTA. It has been found that dehydration reactions were uniformly carried out in the fluidized bed reactor and only hemihydrate was obtained at 90$^{\circ}$ whereas at higher temperatures dehydration reaction progressed further. When gypsum was charged to the reactor preheated at over 140$^{\circ}$, a considerable degree of dehydration occurred before the reactant reached the initially set reactor temperature and in particular, at over 160$^{\circ}$ most of dehydration reaction was performed prior to the present reactor temperature. However, it has been found that gypsum mostly transforms into hemihydrate around the reactant temperature of 140$^{\circ}$ while transformation into anhydrite mostly occurs around $160^{\circ}C.$ When calcium hydroxide was added to gypsum in the reactor, the optimum physical properties of the calcined product were obtained at the weight ratio of $Ca(OH_2)/P_2O_5$ = 3.2.

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Comparative Study on Energy Consumption in Steam-Humidification- and Water-Spray-Humidification-Type Outdoor Air-Conditioning Systems for Semiconductor Manufacturing Clean Rooms (반도체 클린룸용 증기가습 및 수분무가습 외기공조시스템의 에너지소비량 비교연구)

  • Kim, Hyung-Tae;Song, Gen-Soo;Kim, Ki-Cheol;Yoo, Kyung-Hoon;Son, Seung-Woo;Shin, Dae-Kun;Park, Dug-Jun;Kwon, Oh-Myung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.12
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    • pp.1249-1255
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    • 2011
  • In modern large-scale semiconductor manufacturing clean rooms, the energy consumed by the outdoor air-conditioning system during heating, humidification, cooling, and dehumidification of the incoming outdoor air represents about 45% of the total air-conditioning load required to maintain a clean-room environment. In particular, the energy required for humidification of the outdoor air in winter is very high. Therefore, evaluation and comparison of the energy consumption in key humidification systems, viz., steam-humidification and water-spray-humidification systems, used in outdoor air-conditioning systems would be useful to reduce the outdoor air-conditioning load in clean rooms. In the present study, an experiment with an outdoor air flow of 1000 $m^3$/h was conducted to compare the air-conditioning process and energy consumption in outdoor air-conditioning systems with electrodeboiler steam humidifiers and air-washer water spray humidification systems. The experimental results showed that the water-spray-humidification-type outdoor air-conditioning system consumed less electrical power than did the steam-humidification-type system and was more energy efficient during winter.

Studies on the Activated Sludge of Food Industries for Animal Feed -Part 1. Chemical composition of Brewery's Activated Sludge- (식품공장 폐수 활성오니(活性汚泥)의 사료화에 관한 연구 -제1보 : 맥주공장 오니(汚泥)의 화학조성에 관하여-)

  • Ki, Woo-Kyung;Park, Taek-Kyu
    • Korean Journal of Food Science and Technology
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    • v.9 no.4
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    • pp.291-294
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    • 1977
  • Some chemical analysis of brewery's activated sludge were carried out in order to utilize it for animal feed. And results obtained were as follows. 1. Brewery's sludge, sun-dried for 3 days, contained 15.4% of water, 40.47 of crude protein, 4.02% of crude fiber, 13.3% crude ash and 19.4% nitrogen-free extract. 2. Total amino acid content of the brewery's sludge was 38% of its dry basis. The amounts, of all essential amino acids contained except tryptophan was enough for chicken growing and, especially, among the essential amino acids, the contents of leucine, isoleucine, phenylalanine, tyrosine, glycine and serine were two or three times as much as its need. 3. Other minerals contents except Magnesium and Cupper, were considerably low for animal feed.

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Investigation of Shear Design Expressions of Large-Diameter Concrete-Filled Steel Tubes(CFT) (대구경 콘크리트 충전형 합성기둥의 전단 설계식 분석)

  • Jung, Eun Bi;Yeom, Hee Jin;Yoo, Jung Han
    • Journal of Korean Society of Steel Construction
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    • v.27 no.4
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    • pp.399-410
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    • 2015
  • Concrete filled steel tube(CFT) has outstanding deformation capacity and strength in comparison with reinforced concrete or steel tube. CFT drilled shaft, which is developed large shear force due to seismic load and soil liquefaction, is designed as large diameter. However, shear design equations of the current standards do not consider bond stress of CFT and it results in extremely conservative design. Currently, previous studies for improving shear equations scarcely exist and are impossible applied to large CFT drilled shafts since these studies focus on only small scale experimental research. In this study, eventually to propose improving shear equation of large diameter CFT, it is preliminary research to compare and investigate the previous studies and current standards.

Optimization of L-leucine Fermentation (L-leucine 발효의 최적화)

  • 신현철;하구선;조영제;전영중;김성준;이재홍
    • Microbiology and Biotechnology Letters
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    • v.20 no.6
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    • pp.677-680
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    • 1992
  • The effects of pH, temperature and oxygen transfer rate(OTR) on L-Ieucine fermentation were investigated employing Corynebacterium glutamicum CH 1516 in 71 fermentor. The optimum pH, temperature and OTR were determined to be 7.0, $30^{\circ}C$ and 0.21 kmole $O_2$/$m^3{\cdot}hr$, respectively. For the values of OTR lower than 0.19 kmole $O_2$/$m^3{\cdot}hr$ a significant amount of lactic acid was accumulated, while the packed cell volume(PCV) was rapidly increased at higher OTR values above 0.23 kmole $O_2$/$m^3{\cdot}hr$ and glutamic acid was produced to some extent. Scale-up studies for L-Ieucine fermentation which was carried out in 12001 pilot scale fermentor reaffirmed the results of 71 fermentation. The optimum redox potential value for L-Ieucine production was found to be -150 to -170 mY.

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A Reform Proposal of Involuntary Commitment Law Under the Revised Mental Health Act of 2016 - as well as of Article 947-2 (2) of Civil Code - (개정 정신건강복지법상 비자의입원 규제에 대한 입법론적 고찰 - 민법 제947조의2 제2항의 검토를 겸하여 -)

  • Lee, Dongjin
    • The Korean Society of Law and Medicine
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    • v.19 no.2
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    • pp.99-137
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    • 2018
  • Under the Korean law, there are two routes of involuntary civil commitment of the mentally-ill: involuntary commitment process under the Mental Health Act (MHA) and the guardian's commitment backed up by family court approval under article 947-2 (2) of the Civil Code. Despite of the recent fundamental revision of MHA in 2016, the Korean involuntary commitment law has still serious flaws, especially the lack of due process like prior notice, hearing, and independent guardian ad litem for the mentally-ill, which has been pointed out also by the Korean Constitutional Court. Thus, a re-revision is inevitable, and this time, we should proceed to rebuild the underlying structure of involuntary commitment. In this regard, it is crucial to eliminate the old-fashioned and unjustifiable burden as well as power of the so-called responsible person to protect the mentally-ill and to readjust the causes and standings to petition of the various types of involuntary commitment process. Also it is necessary to repeal involuntary commitment by guardian under the Civil Code, article 947-2 (2), which can no longer harmonize with modern involuntary commitment system.