• Tribology and Lubricants
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• v.40 no.2
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• pp.39-46
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• 2024

The Morton effect (ME) is an instability phenomenon occurring in rotating machineries supported by fluid film bearings and is induced by the thermal deformation of the overhung mass, which is a part of the rotating shaft. Herein, we describe the ME during the high-speed balancing test of a 20 MW class steam turbine. Additionally, to predict the rotating speed at which the ME occurs, we apply the sensitivity vector theory for the steam turbine. During the operation of the steam turbine, we observe a continuous increase in vibration and hysteresis near the rated speed, which is typical of the ME. Increasing the temperature of the lubricating oil supplied to the bearings from 40 to 60℃ suppresses the occurrence of the ME. The rotordynamic analysis for the steam turbine suggests the existence of a mode in which the overhung mass undergoes significant deformation near the rated speed, and we presume that such a mode will increase the occurrence of the ME. The predicted rotating speed of ME occurrence, obtained through the sensitivity vector method, correlates with the test results. Moreover, increasing the temperature of the supplied lubricating oil mitigates the occurrence of ME by reducing the sensitivity between the temperature deviation vector and unbalance mass vector.

• Journal of Broadcast Engineering
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• v.18 no.2
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• pp.178-184
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• 2013

In this paper, we propose an efficient parallelization technique of PU-level motion estimation (ME) in the next generation video coding standard, high efficiency video coding (HEVC) to reduce the time complexity of video encoding. It is difficult to encode video in real-time because ME has significant complexity (i.e., 80 percent at the encoder). In order to solve this problem, various techniques have been studied, and among them is the parallelization, which is carefully concerned in algorithm-level ME design. In this regard, merge estimation method using merge estimation region (MER) that enables ME to be designed in parallel has been proposed; but, parallel ME based on MER has still unconsidered problems to be implemented ideally in HEVC test model (HM). Therefore, we propose two strategies to implement stable parallel ME using MER in HM. Through experimental results, the excellence of our proposed methods is shown; the encoding time using the proposed method is reduced by 25.64 percent on average of that of HM which uses sequential ME.

• Journal of Pharmaceutical Investigation
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• v.30 no.4
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• pp.273-278
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• 2000

Several topical preparations containing lidocaine, a widely used local anesthetic agent, have been developed and marketed recently for the treatment of premature ejaculation. In this study, microemulsion(ME)-based hydrogels containing lidocaine were prepared by dispersing ME to hydrogel bases such as Carbopol, sod. alginate, and sod. carboxymethylcellulose. Lidocaine-containing ME was thermodynamically stable over 6 months and had a diameter ranging from 10 to 100 nm. In vitro skin penetration of lidocaine from ME-based hydrogels followed apparent zero-order kinetics. ME-based hydrogel showed higher drug penetration during fifteen minutes after application than alcoholic hydrogel, reference preparation. Tail flick test in rat was introduced to compare in vivo local anesthetic effects of different hydrogels, and the results showed that ME-based hydrogels are superior to other hydrogels. In optical microscopy, recrystallization of lidocaine was observed within 5 min after application of reference hydrogel, but there was no change in ME-based hydrogels even after 30 minnute. These results indicated that ME-based hydrogels had some advantages in skin penetration, anesthetic effect and physical stability compared with alcoholic hydrogels. Finally it is possible to conclude that ME-based hydrogels containing lidocaine is a good topical drug delivery system for the treatment of premature ejaculation.

• BMB Reports
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• v.34 no.1
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• pp.90-94
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• 2001

The mutagenic activity of chitosan oligosaccharide and its antimutagenic effect against 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) were investigated using the Salmonella/Ames test. No mutagenic activity was found in the Salmonella typhimurium strains TA 98 and TA 100, either with or without S9 activation. In contrast, chitosan oligosaccharide showed an inhibitory effect on the mutagenic activity of the cooked food mutagen, MeIQx, in the presence of S9. The influence of chitosan oligosaccharide on the genotoxicity of MeIQx was examined using a host-mediated assay in mice. The oligosaccharide was administered for 14 consecutive days (intragastric application at doses of 0.1 or 0.5 g/kg body wt) to mice. S. typhimurium TA 98 was given intravenously before an oral dose of MeIQx (4.5 mg/kg body wt.). The number of $his^+$ revertants were determined from the Ever of mice. The intragastric application of oligosaccharide led to a 47% reduction in the number of mutants induced by MeIQx (p<0.05). These results suggested that chitosan oligosaccharide had antimutagenic properties against MeIQx in vitro and in vivo.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1258-1265
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• 2007

Metabolizable energy (ME) required for basal metabolism, activity and growth was considered as the criterion for targeting specific increases in body weight (100 g/week) of broiler chicks during the grower phase (5-20 weeks) and its impact was evaluated on breeder performance. Broiler female chicks (460) from a synthetic dam line were randomly distributed to 4 test groups with 23 replicates of 5 birds each and housed in cages. The first group (ME-100) was offered a calculated amount of ME by providing a measured quantity of grower diet (160 g protein and 2,600 kcal ME/kg) which increased with age and weight gain (133-294 kcal/bird/day). The other three groups were offered 10 or 20% less ME (ME-90 and ME-80, respectively) and 10% excess ME (ME-110) over the control group (ME-100). From 21 weeks of age, a single breeder diet (170 g protein and 2,600 kcal ME/kg) was uniformly fed to all groups and the impact of grower ME restriction on breeder performance evaluated up to 58 weeks. The targeted body weight gain of 1,600 g in a 16-week period was achieved by pullets of the ME-100 group almost one week earlier by gaining 8.7 g more weight per week. However, pullets in the ME-90 group gained 1,571 g during the same period, which was closer to the targeted weight. At 20 weeks of age, the conversion efficiency of feed (5.21-5.37), ME (13.9-14.1 kcal/g weight gain) and protein (0.847-0.871 g/g weight gain), eviscerated meat yield, giblet and tibia weights were not influenced by ME restriction, but the weights of abdominal fat and liver were higher with increased ME intake. Reduction of ME by 10% in the grower period significantly delayed sexual maturity (169.3 d), but increased egg production (152.5 /bird) with better persistency. Improved conversion efficiency of feed, ME and protein per g egg content were also observed in this group up to 56 weeks. The fertility and hatchability at 58 weeks of age were higher in the ME-90 group compared to the control and 10% excess ME feeding. In conclusion, the present study revealed the possibility of achieving targeted weight gain in broiler growers by feeding measured quantities of ME during the rearing period with consequential benefits in breeder performance.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.915-916
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• 2005

The high power RF system for the PEFP 20MeV proton accelerator composed of the 3MeV RFQ and the 20MeV DTL has been installed. The klystron for the RFQ was tested up to 600kW and operated routinely to drive the RFQ in a pulse mode operation. The klystron for the DTL which consists of 4 tanks was tested up to 800kW in pulse mode operation. The pulse width and repetition rate was 50${\mu}s$ and 1Hz respectively. The high power RF system has been operated to drive each accelerating structure and will be used to accelerate 20MeV proton beam.

• Proceedings of the Safety Management and Science Conference
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• 2008.04a
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• pp.295-299
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• 2008

This paper discusses tests of factor effect or contrast by the use of saturated design $k^n$ factorial design. The nine nonparametric rank measures in normality test using normal probability pot are proposed. Length's PSE(Pseduo Standard Error) test [4] which relies on the concept of effect sparsity is also introduced and extended to the margin of error(ME) and Simultaneous margin of error(SME).

• Proceedings of the Korea Information Processing Society Conference
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• 2009.04a
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• pp.462-465
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• 2009

모바일 응용 S/W GUI를 기존의 매뉴얼을 보고 테스트 하는 단계적이고 수동적인 방법을 탈피하여 사용자 중심의 시나리오를 통하여 자동으로 GUI를 테스트 하는 것을 목적으로 한다. 제시한 테스트 방법은 사용자 중심의 UI를 설계하여 간편하고, 정확하게 테스트 할 뿐만 아니라 테스트케이스를 재사용하는 환경을 지원한다. 제안한 자동화 도구는 시나리오 기반의 정확한 테스트와 재사용성을 높인 테스트 도구로서 기존 테스트 도구와 기능적인 비교를 통하여 성능을 확인하였다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2012.11a
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• pp.163-166
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• 2012

본 논문에서는 차세대 비디오 표준인 High Efficiency Video Coding(HEVC)의 영상 부호화 과정의 시간복잡도 감소를 위한 효율적인 Prediction Unit(PU)레벨 움직임예측(Motion Estimation, ME) 병렬화의 구현 기법을 제시하고자 한다. 움직임예측 과정은 부호화기에서 80%의 복잡도를 차지하는 과정으로 고속 부호화의 걸림돌이 되고 있다. 이를 해결하기 위한 방법으로 제안된 것이 움직임예측 알고리즘의 병렬화이다. 알고리즘 수준에서 ME 의 일부인 Merge Estimation 의 병렬화를 위해서 Merge Estimation Region (MER)기반의 ME 방법이 제안되었다. 하지만 HEVC Test Model reference software(HM)에 반영된 MER 을 이용하여 실제로 병렬화된 ME 를 구현하는 과정에서는 알고리즘 측면에서 아직 고려되지 않은 문제들이 존재한다. 이에 본 논문에서는 MER 을 사용한 안정적인 병렬 ME 를 구현하기 위한 전략으로 각 PU 의 정보를 독립적으로 사용하기 위한 부분 순차화 방법과 메모리 접근제한을 이용한 병렬화 방법을 제시한다. 실험을 통해 본 연구의 우수성이 확인되었는데, 제안된 방법에 기반을 둔 구현에서 순차적인 ME 를 이용한 부호화기 대비 평균 25.64%의 전체 부호화 과정 시간의 감소가 나타났다.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.416-423
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• 1998

The fungicidal effects of four commercial fungicides, two herbicides and two insecticides have been examined on Fusarium udum, causing wilt disease of pigeonpea in vitro and in vivo. The fungicides Bavistin and MeMc inhibited the growth of the test pathogen completely at 8 and 30 ppm. The herbicide Butachlore inhibited the growth of the test pathogen up to 80.4%. The insecticides, Ekalux and Thiodane partially inhibited the radial growth at 1000 ppm. In unsterilized and sterilized soil MeMc was most effective in controlling the disease in comparison to Bavistin and Ekalux. Maximum rhizosphere fungal population was recorded in MeMc amended soil and minimum in case of Bavistin.