• 펄프종이기술
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• 제42권2호
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• pp.35-40
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• 2010

Variations in hexeneuronic acid content in hardwood alkaline pulps were investigated to evaluate their contribution to kappa number. Out of diverse chemical pulps the highest hexeneuronic acid content were measured in yellow poplar kraft pulping, which was assumed to enhance ca. 7.0 of kappa number determined by acid permanganate consumption. In yellow poplar soda-anthraquinone pulping, hexeneuornic acid was contributed to increment of 5.0-6.0 kappa number. In eucalyptus alkaline pulping, hexeneuronic acid content was not significantly different from soda-anthraquinone pulping. Increment of Kappa number by hexeneuronic acid was 4.5-5.6 depending on pulping method and pulping time at target temperature.

• 한국전문물리치료학회지
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• 제7권1호
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• pp.32-37
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• 2000

The purpose of this study is to determine the effects of exercise training on the strength and balance ability of the elderly. The results of this study are: 1) After 8 weeks exercise training, knee muscle strength showed a significant increment. 2) After exercise training, forward functional reach and balance index of KAT 2000 showed a significant increment. Results indicate that strengthening exercise can result in improved muscle strength and balance in the elderly. Further studies are required to show long-term effects of exercise training on the elderly.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.689-694
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• 2000

The traditional concept after Terzaghi was that consolidation was the dissipation process of pore water pressure compatible to external loading which was generated immediately after the loading. However, a theory of one-dimensional consolidation based on elasto-viscous liquid model proposed by Yoshikuni(1994) explained that the process of primary and secondary consolidation was considered to be not a simple process of dissipation of pore water pressure but a simultaneous process of dissipation and generation by external loading. This study attempts to demonstrate general consolidation behaviour of clayey soils including effects of consolidation history, load increment and thickness of cohesive layer by one-dimensional Finite Difference Method(F.D.M) analysis from the viewpoint of elasto-viscous consolidation theory.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.248-250
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• 2004

Following the needs for increment of public transportation system electric railroad system should be expended. There are several solutions to expend. One of these solutions is to reduce the interval between two railroad vehicles. However, it cannot be reduced too much because reduction of interval means increment of loads and induces supplying voltage decrement. In this paper, voltage variation according to railroad intervals is simulated and optimal operation in railroad system is proposed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.449-451
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• 2002

Sheath circulating current rises from the change of sheath mutual impedance which is caused by imbalanced cable system, and different section length between joint boxes. However, mixed burying typo and imbalance section length take many parts of main reasons of sheath circulating current increment in domestic underground transmission power cables. Therefore, the increment reason and variation characteristics of sheath circulating current is analysed with simulation using EMTP/ATPDraw and measuring data of practical cable system which has a problem of exceeding sheath circulating current in this paper.

• Carbon letters
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• 제11권2호
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• pp.90-95
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• 2010

Carbon materials such as graphite and graphene exhibit high electrical conductivity. We examined the electrical conductivity of synthetic and natural graphene powders after the chemical reduction of synthetic and natural graphite oxide from synthetic and natural graphite. The trend of electrical conductivity of both graphene (synthetic and natural) was compared with different graphite materials (synthetic, natural, and expanded) and carbon nanotubes (CNTs) under compression from 0.3 to 60 MPa. We found that synthetic graphene showed a marked increment in electrical conductivity compared to natural graphene. Interestingly, the total increment in electrical conductivity was greater for denser graphite; however, an opposite behavior was observed in nanocarbon materials such as graphene and CNTs, probably due to the differing layer arrangement of nanocarbon materials.

• 대한소아치과학회지
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• 제5권1호
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• pp.47-63
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• 1978

The author studied on the Simplified Oral Hygiene Index in the handicapped children, who are housed by several rehabilitation institution age from 3 to 17 year in Seoul area and 439 normal children as a control group. The obtained results are as follows: 1) In the Oral Hygiene Index(OHI), The handicapped children showed remarkable increment compared to normal children(The Index score was 2.00 in cerebral palsy children, 1.94 in poliomyelitis, 1.79 in other's diseased children, in 1.01 in normal children) and the score was increased as age increment. 2) In the OHI of the handicapped children, male was higher than female. 3) Dental calculus deposition in the handicapped children was severe in the lower anterior teeth and least in the upper anterior teeth. 4) Dental calculus Index of the handicapped children was comparatively higher in the region which had higher food debris index. 5) As the conculusion of this study, we found that continuous and active dental enlightenment and treatment for oral health in the handicapped children are necessary.

• 대한기계학회논문집
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• 제18권6호
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• pp.1455-1464
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• 1994

A new and efficient algorithm for the integration of the thermal-elasto-plastic constitutive equation is proposed. While it falls into the category of the return mapping method, the algorithm adopts the three point approximation of plastic corrector within one time increment step. The results of its application to a von Mises-type thermal-elasto-plastic model with combined hardening and temperature-dependent material properties show that the accurate iso-error maps are obtained for both angular and radial errors. The accuracy achieved is because the predicted stress increment in a single step calculation follows the exact value closely not only at the end of the step but also through the whole path. Also, the comparison of the computational time for the new and other algorithms shows that the new one is very efficient.

• 한국공작기계학회논문집
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• 제12권4호
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• pp.29-35
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• 2003

The rotating machineries always generate harmonic frequencies of their own rotating speed, and increment of vibration amplitude affects to the equipments which connected to the vibrational source and causes industrial calamities. The life cycle of equipments can be extended and damages to the human beings could be prevented by identifying the cause of malfunctions through prediction of the increment of vibration and records of vibrational history. In this study, therefore, diagnostic expert algorithm for the centrifugal pump is developed by integrating fuzzy inference method and signal processing techniques. And the validity of the developed diagnostic system is examined via various computer simulations.

• 대한기계학회논문집
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• 제12권4호
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• pp.631-641
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• 1988

본 연구에서는 선형 탄성 해석의 결과를 이용하여 초기 하중 증분량을 결정하 는 방법을 제안한다. 또 Crisfield의 방법에서 부분적으로 발생하는 수치적 불안정 을 개선하고 수치 해석의 효율을 제고시키기 위하여 하중 증감의 판정 방법과 변위 증 분 길이의 예측 방법을 제안한다.