• International Journal of Fluid Machinery and Systems
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• 제6권1호
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• pp.11-17
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• 2013

Mini centrifugal pumps having a diameter smaller than 100mm are employed in many fields. But the design method for the mini centrifugal pump is not established because the internal flow condition for these small-sized fluid machines is not clarified and conventional theory is not suitable for small-sized pumps. Therefore, mini centrifugal pumps with simple structure were investigated by this research. Splitter blades were adopted in this research to improve the performance and the internal flow condition of mini centrifugal pump which had large blade outlet angle. The original impeller without the splitter blades and the impeller with the splitter blades were prepared for an experiment. The performance tests are conducted with these rotors in order to investigate the effect of the splitter blades on performance and internal flow condition of mini centrifugal pump. On the other hand, a three dimensional steady numerical flow analysis is conducted with the commercial code (ANSYS-CFX) to investigate the internal flow condition in detail. It is clarified from experimental results that the performance of the mini centrifugal pump is improved by the effect of the splitter blades. Blade-to-blade low velocity regions are suppressed in the case with the splitter blades and total pressure loss regions are decreased. The effects of the splitter blades on the performance and the internal flow condition are discussed in this paper.

• 한국통신학회논문지
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• 제33권6A호
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• pp.685-692
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• 2008

본 논문에서는 Inmarsat (International Marine Satellite) mini-m 시스템의 하향 링크 수신기를 위한 timing recovery 루프를 제안한다. Inmarsat mini-m 시스템 규격에서 요구하는 frequency tolerance는 ${\pm}924$ Hz (signal bandwidth: 2.4 kHz) 이며, timing acquisition 시간은 하나의 UW (Unique Word) 신호 구간인 15ms 이기 때문에 주파수 옵셋에 강인하고 UW 신호 구간에서의 빠른 aquisition 이 가능한 루프 설계가 요구된다. 이에 따라 본 논문에서는 주파수 옵셋에 강인하고 빠른 aquisition 이 가능한 timing recovery 루프를 제안하였으며, 제안된 timing recovery 루프는 UW detector와 UW detector에 의해 검출된 UW 신호를 이용한 timing recovery 루프를 연동한 구조이다. UW detector는 주파수 옵셋 환경에서 안정적인 성능을 위해 차동 기반의 noncoherent detector 방식을 적용하였으며, TED (Timing Error Detector) 알고리즘은 기존의 GAD (Gardner Detector) 알고리즘 대신 본 논문에서 제안하는 UW 신호를 이용한 차동 기반의 ELD (Early Late Detector) 알고리즘 적용하였다. 제안된 방식과 기존의 GAD와의 성능 비교를 통해 제안된 방식이 만족스러운 성능과 신뢰성 있는 동작이 가능함을 입증하였다.

• 구강회복응용과학지
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• 제28권2호
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• pp.139-145
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• 2012

본 연구의 목적은 근관세척제로 2.5% Sodium Hypochlorite, 2% chlorhexidine gel, 식염수를 사용하였을 때, Root ZX와 Sybron Mini의 근관장 측정의 정확도를 평가하고자 하는 것이다. 20개의 발치된 사람 치아에서 Donnelly의 gelatin technique으로 측정하였다. Digital caliper를 이용해 0.01 mm 단위까지 각 전자 근관장 측정기의 0.5와 0.0 level에서 전자 근관장을 측정하였다. 각 측정은 세척제 종류에 따라 세 번식 반복해서 측정하였다. 세 가지 세척제에서 Sybron Mini와 Root ZX의 정확도는 유의한 차이가 없었으며, 제조사의 지시 (Sybron Mini의 0.0 level과 Root ZX의 0.5 level)에서 전자 근관장 측정)에 따라 사용되었을 때 세척제에 따른 전자 근관장 측정기의 정확도는 유의한 차이가 없었다. Root ZX와 Sybron Mini의 사용 시 제조사의 지시대로 사용한다면, 근관세척제으로서 2.5% Sodium Hypochlorite, 2% chlorhexidine gel, 식염수의 사용은 근관장 측정의 정확도에 영향을 미치지 않는다.

• Imaging Science in Dentistry
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• 제47권3호
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• pp.141-147
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• 2017

Purpose: The objective of this study was to compare the outcomes of surgical mini-implant placement when potential mini-implant sites were scanned using a lower-dose $180^{\circ}$ acquisition protocol versus a conventional $360^{\circ}$ acquisition protocol. Materials and Methods: Ten dentate human skulls were used to provide sites for potential mini-implant placement. The sites were randomly divided into 2 groups: $360^{\circ}$ and $180^{\circ}$ cone-beam computed tomography (CBCT) acquisition protocols. A small-volume $180^{\circ}$ CBCT scan and a $360^{\circ}$ CBCT scan of each site were acquired using a Morita Accuitomo-170 CBCT machine and then a mini-implant was placed. A follow-up $360^{\circ}$ CBCT scan was done as a gold standard to evaluate the location of the mini-implant and root perforation. Two raters evaluated the scans. Results: Ninety-eight percent of the mini-implants placed did not perforate any root structure. Two percent of the sites had an appearance suggestive of perforation. On a Likert scale, both raters agreed that their subjective evaluation of the diagnostic quality of the protocols, ability to make and read measurements of the sites, and preferences for the specified diagnostic task were comparable. The Cohen kappa showed high inter-rater and intrarater agreement. Conclusion: In this ex vivo study, we found that the $180^{\circ}$ rotational acquisition was as effective as the conventional $360^{\circ}$ rotational acquisition for the preoperative evaluation of potential mini-implant sites.

• Clinical and Experimental Reproductive Medicine
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• 제21권3호
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• pp.261-266
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• 1994

Semen preparation for Assisted Reproductive Technology(ART) involves the separation of the motile sperm from non-motile, dead sperm, cellular debris and seminal fluid. The aim of this study is to compare the motile sperm recovery rate and motility index of different sperm preparation method(swim-up method, 80% isotonic continuous percoll method, two-layer discontinuous percoll method, mini-percoll method). In Mini-Percoll method, pellets from patients were suspended in 0.3ml of medium and layerd on a discontinuous percoll gradient consisting of 0.3ml each of 50, 70, 95% isotonic percoll. All semen samples are divided into normal and subnormal sperm group(oligo-, astheno-, oligoasthenozoospermia). Especially, we evaluated the effect of mini-percoll method in subnormal sperm group. In normal sperm group, mini-percoll method and two layer discontinuous percoll method (40%/80%) allowed increasing of motile sperm recovery rate. But motility index was higher in swimup method than the other methods. In subnormal sperm group, mini-percoll method has advantages as compare with the other methods in motile sperm recovery rate and motility index. These results suggest that modified mini-percoll method could be certainly a valuable tool in some cases of severe male factor sperm.

• 한국산학기술학회논문지
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• 제12권4호
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• pp.1675-1683
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• 2011

한국의 클러스터사업은 광역발정정책의 추진과 전국적인 산업단지 연계를 위해 구조적 변화를 추진해 왔다. 정부는 산업단지내로 연구소, 지원기관, 대학을 끌어들이고 밀접한 협력 네트워크를 통한 성장잠재력을 제고시키기 위하여 많은 노력을 기울여 왔다. 특히 미니클러스터는 산학연과 지원기관이 참여하는 통합 협의체로써 네트워크 활동을 통해 각종 지원을 제공하고 산학연 협력을 통한 사업기회를 발전시키는 등 다양한 네트워크 활동을 수행하였다. 본 논문은 미니클러스터의 자생적이고 지속가능한 성장을 달성하기 위한 세 가지 전략을 제시한다. 무엇보다 먼저 참여회원들을 유인할 수 있는 유익한 컨텐츠를 제공하여야 한다. 다음으로 미니클러스터 이니셔티브를 추진할 필요가 있다. 마지막으로 협력적 문화를 조성할 필요가 있다.

• 전력전자학회지
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• 제9권4호
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• pp.37-41
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• 2004

1996년 출시이래, MiniSKiiP은 가격 효과적이고 신뢰성 높은 CIB모듈(Converter-Inverter-Brake chopper)로 인정을 받아왔다. 수백만 개가 팔림에 따라, CIB급 모듈 중에서 시장에서의 리더로서의 자리를 굳혀 왔다. 현재 MiniSKiiP은 대량 생산이 필요한 소형 인버터 제품에 광범위하게 사용되고 있다.(중략)

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.134-136
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• 2003

This paper proposes moving mechanism theory & magnetic core analysis regarding mini magnetic contactor and differential mechanism & bimetal analysis regarding mini thermal overload relay. In shortage of technique, we have experienced many difficulties in magnetic switch development. By this research, we developed core parts about mini magnetic switch and applied the results to optimum mini magnetic switch development

• 마케팅과학연구
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• 제10권
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• pp.187-212
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• 2002

Vietnams urban middle class is strongly value oriented in its shopping behavior. They want fairly good quality and service, but they also factor price into their considerations. In terms of retail patronage, they demand convenience, good service, attractive display, and especially want extensive choice. Brands must be present in multiple types of outlet, or fragile brand loyalties can be broken. Mini supermarkets have become an important part of the retail scene in the past decade, and have successfully introduced the supermarket concept to Vietnam. Many consumers are integrating mini supermarkets into their regular shopping, and are willing to pay the higher prices to gain the benefits of such shopping. However, the mini supermarkets do not adequately meet some of the things they expect from supermarkets. Large supermarkets are just entering the market, and are likely to capture much of the current mini supermarket customer base.

• Journal of Microbiology and Biotechnology
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• 제28권5호
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• pp.821-825
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• 2018

A copy number amplification system for yeast artificial chromosomes (YACs) was combined with simultaneous overexpression of genes integrated into a YAC. The chromosome VII (1,105 kb) was successfully split to 887 kb, 44 kb containing the element for copy number amplification, and a 184-kb split-YAC. The 44-kb split-mini YAC was amplified a maximum of 9-fold, and the activity of the reporter enzymes integrated into the split-mini YAC increased about 5-7-fold. These results demonstrate that the mini-YAC containing a targeted chromosome region can be readily amplified, and the specific genes in the mini-YAC could be overexpressed by increasing the copy number.