• 제목/요약/키워드: local modification

검색결과 262건 처리시간 0.024초

반도체 소자용 구리 배선 형성을 위한 전해 도금 (Electrodeposition for the Fabrication of Copper Interconnection in Semiconductor Devices)

  • 김명준;김재정
    • Korean Chemical Engineering Research
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    • 제52권1호
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    • pp.26-39
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    • 2014
  • 전자 소자의 구리 금속 배선은 전해 도금을 포함한 다마신 공정을 통해 형성한다. 본 총설에서는 배선 형성을 위한 구리 전해 도금 및 수퍼필링 메카니즘에 대해 다루고자 한다. 수퍼필링 기술은 전해 도금의 전해질에 포함된 유기 첨가제의 영향에 의한 결과이며, 이는 유기 첨가제의 표면 덮임율을 조절하여 웨이퍼 위에 형성된 패턴의 바닥 면에서의 전해 도금 속도를 선택적으로 높임으로써 가능하다. 소자의 집적도를 높이기 위해 금속 배선의 크기는 계속적으로 감소하여 현재 그 폭이 수십 nm 수준으로 줄어들었다. 이러한 배선 폭의 감소는 구리 배선의 전기적 특성 감소, 신뢰성의 저하, 그리고 수퍼필링의 어려움 등 여러 가지 문제를 야기하고 있다. 본 총설에서는 상기 기술한 문제점을 해결하기 위해 구리의 미세 구조 개선을 위한 첨가제의 개발, 펄스 및 펄스-리벌스 전해 도금의 적용, 고 신뢰성 배선 형성을 위한 구리 기반 합금의 수퍼필링, 그리고 수퍼필링 특성 향상에 관한 다양한 연구를 소개한다.

Does intrauterine injection of low-molecular-weight heparin improve the clinical pregnancy rate in intracytoplasmic sperm injection?

  • Kamel, Ahmed Mohamed;El-Faissal, Yahia;Aboulghar, Mona;Mansour, Ragaa;Serour, Gamal I;Aboulghar, Mohamed
    • Clinical and Experimental Reproductive Medicine
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    • 제43권4호
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    • pp.247-252
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    • 2016
  • Objective: Heparin can modulate proteins, and influence processes involved in implantation and trophoblastic development. This study aimed to assess the improvement of clinical pregnancy and implantation rates after local intrauterine injection of low-molecular-weight heparin (LMWH) in patients undergoing intracytoplasmic sperm injection (ICSI). Methods: A randomised case/control design was followed in women scheduled for ICSI. The study arm was injected with intrauterine LMWH during mock embryo transfer immediately following the ovum pickup procedure, while the control arm was given an intrauterine injection with a similar volume of tissue culture media. Side effects, the clinical pregnancy rate, and the implantation rate were recorded. Results: The pregnancy rate was acceptable (33.9%) in the LMWH arm with no significant reported side effects, confirming the safety of the intervention. No statistically significant differences were found in the clinical pregnancy and implantation rates between both groups (p= 0.182 and p= 0.096, respectively). The odds ratio of being pregnant after intrauterine injection with LMWH compared to the control group was 0.572 (95% confidence interval [CI], 0.27-1.22), while the risk ratio was 0.717 (95% CI, 0.46-1.13; p= 0.146). No statistical significance was found between the two groups in other factors affecting implantation, such as day of transfer (p= 0.726), number of embryos transferred (p= 0.362), or embryo quality. Conclusion: Intrauterine injection of LMWH is a safe intervention, but the dose used in this study failed to improve the outcome of ICSI. Based on its safety, further research involving modification of the dosage and/or the timing of administration could result in improved ICSI success rates.

Bone Morphogenic Protein-2 (BMP-2) Immobilized Biodegradable Scaffolds for Bone Tissue Engineering

  • Kim, Sung-Eun;Rha, Hyung-Kyun;Surendran, Sibin;Han, Chang-Whan;Lee, Sang-Cheon;Choi, Hyung-Woo;Choi, Yong-Woo;Lee, Kweon-Haeng;Rhie, Jong-Won;Ahn, Sang-Tae
    • Macromolecular Research
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    • 제14권5호
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    • pp.565-572
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    • 2006
  • Recombinant human bone morphogenic protein-2 (rhBMP-2), which is known as one of the major local stimuli for osteogenic differentiation, was immobilized on the surface of hyaluronic acid (HA)-modified poly$(\varepsilon-caprolactone)$ (PCL) (HA-PCL) scaffolds to improve the attachment, proliferation, and differentiation of human bone marrow stem cells (hBMSCs) for bone tissue engineering. The rhBMP-2 proteins were directly immobilized onto the HA-modified PCL scaffolds by the chemical grafting the amine groups of proteins to carboxylic acid groups of HA. The amount of covalently bounded rhBMP-2 was measured to 1.6 pg/mg (rhBMP/HA-PCL scaffold) by using a sandwich enzyme-linked immunosorbant assay. The rhBMP-2 immobilized HA-modified-PCL scaffold exhibited the good colonization, by the newly differentiated osteoblasts, with a statistically significant increase of the rhBMP-2 release and alkaline phosphatase activity as compared with the control groups both PCL and HA-PCL scaffolds. We also found enhanced mineralization and elevated osteocalcin detection for the rhBMP-2 immobilized HA-PCL scaffolds, in vitro.

G/T 190톤급 한국 대형선망 본선의 저항저감에 대한 연구 (A Study on the Resistance Reduction of G/T 190ton Class Main Vessel in Korean Large Purse Seiner Fishing System)

  • 박애선;이영길;김두동;유진원;하윤진;진송한
    • 대한조선학회논문집
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    • 제49권5호
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    • pp.367-375
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    • 2012
  • In this study, hull form of main vessel of Korean large purse seiner fishing industry is developed for the improvement of resistance performance as well as for the satisfaction to the Standard of Fishing Convention, ILO. Through the modification of reference hull form parameters and local characteristics, the hull form development is carried out. The optimum hull form parameters are searched by Sequential Quadratic Programing(SQP) method with the power estimation method of Holtrop & Mannen. To minimize the wave resistance, bulbous bow parameters are determined by the bulbous bow design method of Alvarino. The plasmatic curve is redesigned from that of the reference hull by using Lackenby method. The resistance performances of the reference and designed hull forms are estimated by using numerical simulation method. Also, the judgment of seakeeping ability and the estimation of intact stability for the designed hull form is carried out. As a result, the optimum hull form is proposed. To verify the improvement of resistance performance, model tests are carried out in towing tank. The results show that the resistance of the designed hull form is about 14% smaller than that of the reference hull from at design speed. A new hull form proposed in this study can contribute to the development of the main vessel hull form of Korean large purse seiner fishing system.

공동체성 지향을 위한 지역사회서비스투자사업의 정책적 쟁점 (An Analysis of Community Service Investment Project by the Framework of Output Analysis and Policy Issue)

  • 배화숙
    • 디지털융복합연구
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    • 제14권1호
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    • pp.53-63
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    • 2016
  • 본 연구는 사회서비스에서 비중이 급격히 확대되고 있는 지역사회서비스투자사업에 초점을 맞추고 의미 있는 발전을 위해 필요한 논의가 무엇인가를 찾고자 하였다. 산물분석 틀을 이용하여 지역사회서비스투자사업의 내용을 분석하고 사업을 구성하는 사회적 선택의 근거가 되는 가치를 축으로 분석하였다. 지역사회서비스투자사업의 내용과 가치 분석을 토대로 도출한 정책적 쟁점은 다음과 같다. 첫째, 지역사회서비스투자사업은 지금보다 더 '지역'에 초점을 맞출 필요가 있다. 둘째, 시민의 개별성에 초점을 맞추는 사회서비스가 더 중요해질수록 주민참여에 기반한 지역사회서비스투자사업의 '지속가능성'에 대해 생각할 필요가 있다. 셋째, 지역사회의 '공동체 형성'과 관련하여 지역사회서비스투자사업의 목표 수정에 대해 논의할 필요가 있다. 이를 위해 지역주민의 의사결정 통로 부재, 소득 기준 대상 선정, 사업명칭에서 '투자'라는 용어의 적절성에 대해 재검토가 필요하다.

리눅스 클러스터에서 MPI 기반 병렬 프로그램의 동적 동시 스케줄링 기법 (A Dynamic Co-scheduling Scheme for MPI-based Parallel Programs on Linux Clusters)

  • 김혁;이윤석
    • 한국컴퓨터정보학회논문지
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    • 제13권1호
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    • pp.29-35
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    • 2008
  • 빈번한 메시지를 주고받는 MPI 기반의 병렬 프로그램에서 효과적으로 통신이 이뤄지기 위해서는 송수신 프로세스들이 각 노드에서 동시에 스케줄되어야 한다. 그러나, 일반적으로 클러스터 컴퓨터를 구성하는 각 노드는 범용시분할 운영체제를 기반으로 하며, 이 경우 병렬 프로그램을 구성하는 프로세스들은 각 스케줄러에 의해 자율적으로 관리되므로 이들을 동시에 함께 실행시키는 것은 쉽지 않다. 본 연구에서는 리눅스 클러스터에서 효과적으로 병렬 MPI 프로그램을 실행시키기 위해, 메시지 교환 정보를 활용하여 통신에 참여하는 프로세스들이 동시에 스케줄 되는 기법을 제안하고 실제 구현을 통해 성능을 살펴보았다. NPB 병렬 벤치마크의 수행을 통해 측정한 결과에 따르면, 통신량이 높은 프로그램에서 33-56%의 실행 시간 감소 효과를 보였다.

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한국 고속 소형 연안어선의 저항성능 연구 (A Study on the Resistance Performance of Korean High-Speed Small Coastal Fishing Boat)

  • 유진원;이영길;박애선;하윤진;박정규;최영찬
    • 대한조선학회논문집
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    • 제48권2호
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    • pp.158-164
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    • 2011
  • The study on the improvement of resistance performance is very important for coastal fishing boats in Korea, because the prices of fuel oil are gradually risen and the demand of high-speed fishing boats is increased lately. This study is concerned with the improvement of the resistance performance for Korean high-speed small coastal fishing boats. A semi-planing hull form of Korean small coastal fishing boat is selected in the role of initial hull. From the modification of the hull form parameters and the local characteristics of the hull form, the improvement of the resistance performance is achieved. The resistance performances of the initial and the modified hull forms are estimated by using a numerical simulation method. Also, ship model tests are carried out in ship model basin.

하천 만곡부에서의 세굴심 산정식에 관한 연구 (A Study on the Scour Depth Equation in Bight River)

  • 최한규;박제완;박수진
    • 산업기술연구
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    • 제32권A호
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    • pp.47-55
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    • 2012
  • Currently, we only estimate the average flood water level by the cross-sections of the river using one-dimensional numerical analysis when establishing the basic plans. However, the reliability decreases when it comes to the river bend. In river bend, the difference of water-level between the inside and the outside of the river arises by centrifugal force. And it is estimated less than what it could be estimated when establishing the plan with average estimate of flood level. It is apprehended that the exterior of the river will be under-constructed when establishing the scour depth only with the mean depth. In the case of local scour of the abutment, it is difficult to estimate its depth precisely, and it tends to be over-estimated in the case of the empirical formulas. Therefore, the modification considering the deviation of the water depth of the exterior of the river bend is needed. In observing the deviation of each formula in river bend, it is found: Andru's formula for 58%, followed by the Laursen's for 26%, and the C.S.U's for 17% in pier, while it is 44% for Froehlich's formula in abutment. Under the 500CMS of the flood discharge, the deviation of the scour depth between pier and abutment was about 10 %. However, in further flood discharge, it shows 24~58% the biggest in deviation of piers. It is concluded that the scour depth estimate should be done with 2-dimensional numerical analysis.

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지역보건 관련 소지역간 건강증진지표 개발에 관한 연구 (Development of Small Area Health Promotion Indicator for Community Health Initiative)

  • 김춘배;고광욱;박재성;최헌
    • 보건교육건강증진학회지
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    • 제20권1호
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    • pp.19-39
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    • 2003
  • Purpose: Although there is a lot of secondary data available for comparing community health status and planning health policies in terms of large area such as metropolitan cities or provinces, there is restricted data for establishing community health policies of the small areas such as towns, Gun(i.e., districts), and Gu. Specifically, the problems of producing a valuable index for health promotion in small areas are three fold: First, there is not an appropriate index model for measuring a small community health status. Second, a large part of secondary data in the small areas has been produced in an irregular time interval. In addition, all valuable data can not be integrated without time consuming work. Thus this study tries to establish a health promotion index model for assisting community health promotion initiatives of local governments. Methods and materials: Literature review, community health specialist consultation and a questionnaire survey was performed. Results: Based on Dever's model, a prototype of health promotion indicators was proposed and modified by the community health specialists. 15 classification scheme of statistical yearbook reorganized into the six areas. Those six areas were comprised in 24 indicator class with 96 specific indicators. Through further modification processes by a questionnaire survey, we developed a health promotion indicator model that contains six areas with 23 indicator class encompassed by 87 specific indicators. Conclusions: This study proposed a model of health promotion indicator comprised in the six areas with 23 indicator classes for measuring small area health promotion status. However, more specific or additional data in human biology, environment, and socioeconomic data is essential for producing a stronger model for health promotion measurement.

Theoretical construction of solar wind proton temperature anisotropy versus beta inverse correlation

  • 서정준;;김관혁;이동훈
    • 천문학회보
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    • 제37권2호
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    • pp.118.1-118.1
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    • 2012
  • In situ observations from the Wind spacecraft that statistically analyzed the solar wind proton at 1 AU has indicated that the measured proton temperature anisotropies seems to be regulated by the oblique instabilities (the mirror and oblique firehose). This result is in contradiction with the prediction of linear kinetic theory that the ion-cyclotron (for ${\beta}_{\parallel}$ < 2) and parallel firehose (for ${\beta}_{\parallel}$ <10) would dominate over the oblique instabilities. Various kinds of physical mechanisms have been suggested to explain this disagreement between the observations and linear theory. All of the suggestions consider the solar wind as a unoform magnetized plasma. However the real space environment is replete with the intermediate spatio-temporal scale variations associated with various physical quantities, such as the magnetic field intensity and the solar wind density. In this paper we present that the pervasive intermediate-scale temporal variation of the local magnetic field intensity can lead to the modification of the proton temperature anisotropy versus beta inverse correlation for temperature-anisotropy-driven instabilities. By means of quasilinear kinetic theory involving such temporal variation, we construct the simulated solar wind proton data distribution associated the magnetic fluctuations in (${\beta}_{\parallel}$, $T_{\perp}/T_{\parallel}$) space. It is shown that the theoretically simulated proton distribution and a general trend of the enhanced fluctuations bounded by the oblique instabilities are consistent with in situ observations. Furthermore, the measure magnetic compressibility can be accounted for by the magnetic spectral signatures of the unstable modes.

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