• Membrane and Water Treatment
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• 제6권1호
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• pp.15-26
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• 2015

The compact structure and high-quality effluent of membrane bioreactors make them well-suited for decentralized greywater reclamation. However, the occurrence of membrane fouling continues to limit their effectiveness. To address this concern, a unique membrane module configuration was developed for use in a decentralized greywater treatment system. The module featured local aeration directly below a series of inclined membrane bundles, giving the overall module a twisted appearance compared to a module with vertically orientated fibres. The intent of this design was to increase the frequency and intensity of collisions between rising air bubbles and the membrane surface. Material related to the construction of custom-fit modules is rarely communicated. Therefore, detailed design and assembly procedures were provided in this paper. The twisted module was compared to two commercially available modules with diverse specifications in order to assess the relative performance and marketability of the twisted module with respect to existing products. Contaminant removal efficiencies were determined in terms of biochemical oxygen demand, chemical oxygen demand, ammonia, total nitrogen, total phosphorus, and turbidity for each module. Membrane fouling was monitored in terms of permeate flux, transmembrane pressure, and membrane resistance. Following 168 h of operation, the twisted module configuration demonstrated competitive performance, indicating good potential for further development and commercialization.

• Journal of Ginseng Research
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• 제8권2호
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• pp.91-104
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• 1984

This study was conducted to investigate the characteristics of nonstarchy polysaccharides in Korean ginseng, (Panax ginseng C.A. Meyer). The results obtained are as follows. 1. The total sugar content of ginseng roots were decreased with increasing the cultural period. On the other hand, the crude fiber content was increased with that of the ginseng leaves or stems. But the crude fiber in root was much less than that of leaves and stems. 2. The dietary fiber content of ginseng root on 5 years old was 14.20% as neutral detergent fiber, 9.08% as acid detergent fiber, hemicellulose 5.12%, cellulose 7.98% and lignin of 1.10%, respectively. 3. Much more pectin was found in ginseng roots which was cultivated for shooter Period. And it was contained much more in the root than in the leaves and stems. 4. ginseng hemicellulose content in root was 5% to 10%. It was decreased with increasing: cultivated period. Hemicellulose was constituted of xylose, arabinose, glucose, rhamnose and xylose of these sugars was the predominant. 5. X-ray diffraction Pattern of ginseng cellulose showed maximum intensity at tile interplanar angle of 4.1$^{\circ}$.

• 한국동물학회지
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• 제2권2호
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• pp.15-24
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• 1959

Concluding the result of this observation, authors obtained the table showing chromosome numbers which are consisted in each species as follow. Viewing on this result, authors recognized Acrididae are determined the sex with X-O type. 6 species of Family Acrididae and one species of Family Gryllotalpidae (on above table) had already calculated the number of chromosomes by some foreign observers. But another one species (Briodema tuberculatum dilatum STOLL) clarified by authors firstly in this observation. In 2nd spermatocyte of Trilophidia annulata YHUMBERG 1 to 3 Ist constriction satellites were observed, and each of the small bodies was connected with thin fibre and constituted with same or less breadth as the main chromosomes. If those are not the satellites, they should be the super-numerary chromosomes appearing a dot form. In this observation, among 48 species of Family Acrididae which have been found in Korea 18 species were calculated their chromosome numbers which were including 1 species calculated by authors newly. And authors have reobserved the chromosomes of Gryllotalpa africana PALISOT de BEUVOIS of Family Gryllotalpidae which was done by Japanese before.

• 한국재료학회지
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• 제3권2호
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• pp.140-144
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• 1993

열경화성 에폭시 수지의 물성 중 담약성을 개선하기 위해 새로운 반응성첨가제 succinonitrile(SN)을 Diglycidy1 ether of bisphenol A(DGEBA(-4,4'-methylene dianiline(MDA)계에 도입하여 현재 널리 사용되고 있는 유리섬유 복합재료에 매트릭스로 사용될 경우에 있어서 파괴되는 거동을 미시적으로 고찰하였다. 그 결과 post debond friction 에너지가 파괴 거동을 주도하고 있으며, 다음으로 pull-out에너지 그리고 debonding 에너지 순으로 나타났다. 따라서 파괴 거동에 미치고 있는 중요한 요인은 섬유와 매트릭스 간의 경계면 전단 응력이 크게 좌우함을 알 수 있었으며, 이때 반응성 첨가제 SN은 전단응력을 떨어뜨리는 것으로 고찰되었다.

• Journal of Construction Engineering and Project Management
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• 제4권4호
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• pp.41-46
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• 2014

Indian Construction industry is large, volatile, and requires tremendous capital outlays. Typically, the work offers low rates of return in relation to the amount of risk involved. A unique element of risk in the industry is the manner in which disputes and claims are woven through the fibre of the construction process. Delay is generally acknowledged as the most common, costly, complex and risky problem encountered in construction projects. Because of the overriding importance of time for both the Owner and the Contractor, it is the source of frequent disputes and claims leading to lawsuits. The growing rate of delays is adversely affecting the timely delivery of construction projects. Presently construction industries are facing a lot of problems, considering that a paper assess construction stakeholder's perception to the causes of delays and its effects on project delivery. And also one case study is considered in this paper to elicit responses from construction stakeholders. The primary aim of this paper is to identify the perceptions of the different parties regarding causes of delays, the allocation of responsibilities and the types of delays, and method of minimizing the construction delays.

• 전기의세계
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• 제16권2호
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• pp.1-8
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• 1967

From the discovery of Alago's disk, a number of trials and efforts have been concentrated on a small-sized and light-weighted induction motor. They have devoted themseleves, however, mainly to a improvement of cooling effect, a proper weight-distribution of copper and iron and desirable number of slots. In consequence, such an effort restricted only to the field of design, has resulted in unsatisfactory developments in the insulating materials consisting of the main parts of an induction motor. The quality of fibre and paper which are used as class-A insulation materials with their "compound" and "varnish" has been increased to some extent. Similarly Class-B insulation materials like asbest mica has been almost a combination of inorganic and binding materials. But nowadays synthesic chemistry is making a remarkable progress. So it comes possible for us to have silicon resin and other good ones of similar charateristics. And even a thin silicon resin insures us to get excellent heat-pro f and insulation, so a better space factor and cost-down in motor design have come possible in most advanced nations of the world, but not in our country. Furthermore, a consideration of productivity and economy in manufacturing process has been neglected by a majority of engineers. This is more unpleasant und more undesirable. I think this rational method of induction motor design using new synthesic resin will devote in making your productivity and economy better. And the nation-wide standard value of electric motor size is sited here. size is sited here.

• Fibers and Polymers
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• 제5권4호
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• pp.264-269
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• 2004

The present paper deals with improvement in disperse dyeablility as well as imparting of cationic dyeablility to difficultly dyeable polypropylene by a melt blending technique. Isotactic polypropylene (PP) was blended with fibre grade polybutylene terephthalate (PBT), cationic dyeable polyethylene terephthalate (CDPET) and polystyrene (PS), individually. The resulting binary blends were spun and drawn into fibres at draw ratio 2, 2.5, and 3. The compatibility of blends, structural changes of fibres in terms of X-ray crystallinity, relative crystallinity, sonic modulus, birefringence and thermal stability were examined. The blended fibres were found to be disperse dyeable by the conventional method of high temperature and high pressure dyeing. And this dye ability increased with increase in the level of substitution. PP/CDPET blend also exhibited dyeablility with cationic dyes in addition to that with disperse dyes. The optimum level of blending was predicted keeping in view of tenacity and thermal stability of melt blend fibres. The wash fastness properties of the dyed fibres were found to be of high rate.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2000년도 제26회 펄프종이기술 국제세미나
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• pp.34-39
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• 2000

Today's size of production operations in the packaging paper sector I sconstantly increasing , featuring integral processing systems, high-speed paper machines, and the increased marketing of lower basis weight products. The risk factors involved in these large investments lie more than ever in the available furnish potential and ongoing requirements for further closure of water loops and lower operating costs. A comparison is drawn between recovered paper furnish mixtures used in European mills with regard to fibre properties, strength potential and contaminant content, Both the furnish situation and development trends in modern fluting and testliner machines are instigating concept changes in stock preparation, the approach flow as well as in process water and rejects technology. Developments are currently focussed for example on more efficient debris separation using fine slotted screening, optimized refining , more systematic process water management with loop separation and integral water clarification as well as more efficient removal of microstickies, fillers and fines through appropriate combination of rejects handling and water clarification processes. Product quality differentiation depends decisively on strength characteristics as a function of refining , fines removal , paper machine technology, and sizing . Maximum availability of today's high speed paper machines and , as a result, cost effective production can be ensured by optimum balancing of all subsystems with in the overall concept and by reliable control of problems with contaminants and deposits.

• 한국잠사곤충학회지
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• 제24권2호
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• pp.81-84
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• 1983

견사에 대한 산성염료인 Orange II의 평형수착을 pH 2.2 HCl염욕중에서 온도 50$^{\circ}$, 70$^{\circ}$ 및 9$0^{\circ}C$로 변화시켜, 또한 온도 $50^{\circ}C$에서 pH를 1.5, 2.2 및 4.0으로 조절하여 수착식을 검토하였다. pH 1.5 및 2.2에서의 수착식은 이원 model 즉 Langmuir형과 Nernst형의 합으로 표시됨을 알았다. Langmuir 수착평행상수 $K_{L}$ 은 온도의 상승과 pH의 증가에 따라 감소하였고, Nernst분배계수 $K_{P}$ 도 비슷한 경향을 보였다. 수착 반응은 발열반응임을 알 수 있었고 표준 entropy는 정의 값임을 알았다.

• 한국염색가공학회지
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• 제6권1호
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• pp.8-18
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• 1994

In one bath dyeing system of silk/cellulose acetate fiber blend fabric with acid /disperse dyes, adsorption behavior of acid dyes and disperse dyes on silk and cellulose acetate fabrics were examined. In the dyeing of cellulose acetate with C. I. Disperse Red 19(Red 19) and C. I. Disperse Red 60(Red 60) at 8$0^{\circ}C$ and 10$0^{\circ}C$, dye uptake with Red 19 was higher than that with Red 60. When the silk/cellulose acetate dyed with Red 19 and Red 60 at 10$0^{\circ}C$, dye uptake on cellulose acetate was influenced by affinity of the dye to the silk fabric dyed together. When the silk/cellulose acetate dyed with Blue 80/Red 19 and Blue 80/Red 60 at 10$0^{\circ}C$, color of cellulose acetate dyed with Red 19 and Red 60 was not influenced by Blue 80 but silk dyed with Blue 80 was influenced by Red 19 and Red 60. Interrelation of K/S value and Munsell value was scarcely any but showed the change tendency of K/S value.