• Title/Summary/Keyword: Dominant Factor

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Optimization of Swirl Ratio of Intake Port in 11L LPLi Engine (11L급 LPLi방식 대형엔진의 흡기스월비 최적화 연구)

  • 이진욱;강건용;민경덕
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.3
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    • pp.99-105
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    • 2003
  • The configuration of intake port is a dominant factor of inlet air flow and mixture formation in an engine. In this study, as an available technology to optimum intake port, the flow box system using resine has been applied. So we presents a methodology for estimating inlet flow characteristics in this paper. This quantified experimental result shows good agreements with visualization data in a cylinder. We obtained the optimal value of swirl ratio and flow coefficient under steady flow rig test for new development of intake port for heavy-duty engine. From this results, the cylinder heat with a good evaluated swirl flow characteristics was developed and adapted for a 11L heavy-duty engine using the liquid phase LPG injection (LPLi) system. This .research expects to clarify major factor that make the intake port efficiently.

Investigation on the Relationship between Mass Transfer and Reaction within the Washcoat of Monolith Type Micro-scale Catalytic Combustor (모노리스 타입 마이크로 촉매 연소기의 담층 내부 물질전달 및 반응 관계에 관한 연구)

  • Lee, Gwang Goo;Suzuki, Yuji
    • Journal of the Korean Society of Combustion
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    • v.20 no.2
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    • pp.46-53
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    • 2015
  • The relationship between mass transfer and reaction within the washcoat is investigated in a monolith type micro-scale Pt-catalytic combustor. Nondimensionalized balance equation of butane is applied in a simplified washcoat geometry having the shape of slab. Both Thiele modulus and effectiveness factor are considered to compare reaction rate and diffusion rate according to the operation temperature and the diameter of alumina nano-pores. The effect of reaction becomes stronger as the temperature increases, while the effect of diffusion becomes relatively dominant as the diameter of nano-pores increases. From the analysis of butane distribution within the washcoat, design criterion for the thickness of washcoat is discussed.

Optimizations of Air-trap Locations in the Speaker Encloser of Mobile Phone by Injection Molding Simulations (사출성형 시뮬레이션에 의한 휴대폰 스피커 인클로저의 에어트랩 위치 최적화)

  • Park, Ki-Yoon;Park, Jong-Cheon
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.5
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    • pp.85-90
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    • 2011
  • In this paper a design procedure via computer-aided molding simulation is presented to optimize the air-trap locations in a speaker encloser of mobile phone. The molding flow simulation reveals that the race-tracking phenomenon is the dominant feature in the current mold design. In obtaining an optimal filling pattern, the local modifications of the wall thickness such as in a flow leader attachment are considered as the primary control factor, and both the gate position and the filling time become the secondary control factor. In the one-at-a-time approach, the last location to be filled in the mold cavity could be successfully moved to the extremities of the part, allowing a natural ventilation of entrapped air through the mold parting plane.

iRhoms; Its Functions and Essential Roles

  • Lee, Min-Young;Nam, Ki-Hoan;Choi, Kyung-Chul
    • Biomolecules & Therapeutics
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    • v.24 no.2
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    • pp.109-114
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    • 2016
  • In Drosophila, rhomboid proteases are active cardinal regulators of epidermal growth factor receptor (EGFR) signaling pathway. iRhom1 and iRhom2, which are inactive homologs of rhomboid intramembrane serine proteases, are lacking essential catalytic residues. These are necessary for maturation and trafficking of tumor necrosis factor-alpha (TNF-${\alpha}$) converting enzyme (TACE) from endoplasmic reticulum (ER) to plasma membrane through Golgi, and associated with the fates of various ligands for EGFR. Recent studies have clarified that the activation or downregulation of EGFR signaling pathways by alteration of iRhoms are connected to several human diseases including tylosis with esophageal cancer (TOC) which is the autosomal dominant syndrom, breast cancer, and Alzheimer's disease. Thus, this review focuses on our understanding of iRhoms and the involved mechanisms in the cellular processes.

Resolution analysis of Fourier Hologram using integral imaging

  • Chen, Ni;Park, Jae-Hyeung;Kim, Nam
    • Proceedings of the Optical Society of Korea Conference
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    • 2009.10a
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    • pp.331-332
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    • 2009
  • We present an analysis on the quality factors of the Fourier hologram generated from multiple orthographic view images of three-dimensional object. In the analysis, we analyze both the maximum size of the reconstructed object and its spatial resolution. For the maximum size of the reconstruction, we found that the main factor is the orthographic projection angle interval. Too large projection angle interval causes overlapping in the reconstruction space domain. For the spatial resolution, there are three factors, i.e. the capturing lens array pitch which determines the spatial sampling rate of the original three-dimensional objects, the maximum orthographic projection angle, and the spatial frequency bandwidth of the object. The dominant factor is determined by the relationship between those three factors.

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Discovering cis-regulatory motifs by combining multiple predictors

  • Chang, Hye-Shik;Hwang, Kyu-Woong;Kim, Dong-Sup
    • Bioinformatics and Biosystems
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    • v.2 no.2
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    • pp.52-57
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    • 2007
  • The computational discovery of transcription factor binding site is one of the important tools in the genetic and genomic analysis. Rough prediction of gene regulation network and finding possible co-regulated genes are typical applications of the technique. Countless motif-discovery algorithms have been proposed for the past years. However, there is no dominant algorithm yet. Each algorithm does not give enough accuracy without extensive information. In this paper, we explore the possibility of combining multiple algorithms for the one integrated result in order to improve the performance and the convenience of researchers. Moreover, we apply new high order information that is reorganized from the set of basis predictions to the final prediction.

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Effects of Disk Thickness and Pemto Slider on Position Error Signal for High TPI Hard Disk Drive (고밀도 디스크 드라이브를 위한 디스크 두께와 Pemto 슬라이더가 PES에 미치는 영향)

  • Han Yun-Sik;Lee Ho Seong;Song Yong-Han
    • Transactions of the Society of Information Storage Systems
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    • v.1 no.1
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    • pp.23-28
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    • 2005
  • This paper investigates the effects of disk thickness and Pemto slider on PES(position error signal) for high TPI(track per inch) drives above 150kTPI at early stage of their development. In order to reduce the disk flutter which becomes a dominant contributor to the TMR, the thicker disks with both 63 and 69mi1 have been used. Also, PES of a Pemto slider with thinner thickness than Pico slider has been estimated to decrease the conversion factor of disk motion in axial direction to head off-track motion. A frequency-domain PES estimation and prediction tool has been developed via measurement of disk flutter and HSA(head stack assembly) forced vibration. It has been validated by the measured PES in drive level. Based on the model and measurement of disk flutter, PES of a drive with the thicker disk and Pemto slider is predicted and their impact is investigated.

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Comparison and analysis the Effect of Vibration Control Sleeper Pads on Gwe-Mok Elevated Railway Bridge in Jeolla Line (전라선 괴목고가교 방진침목패드 시공 전/후 비교 분석)

  • 엄기영;유원희;김지훈
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.924-928
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    • 2002
  • Response of the rail surface is an important factor for the train safety and comfortable travel, and evaluation of vibration at the area along a rail is an important factor for the vibration. The dominant method to reduce the vibration that reach the ground is installing vibration absorber between rall and the under structure. In this paper, we evaluated the vibration reducing effect of using vibration control sleeper pads to slave and earth at certain distance from the sleepers.

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A Study of fracture Mechanics Analysis Methodology for Stress Corrosion Cracks in Pressure Component Weld feints

  • Park, June-soo;Kim, Jong-Min;Pak, Jai-hak;Jin, Tae-eun
    • Proceedings of the KWS Conference
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    • 2003.05a
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    • pp.216-218
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    • 2003
  • A fracture mechanics analysis methodology for stress corrosion cracks (SCCs) existing in the Alloy 600 nozzle weld joint for control rod drive mechanisms (CRDMs) of pressurized water reactor is studied. Effects of weld residual stresses on the sub-critical crack behavior during the reactor operation are investigated by a fracture mechanics analysis, which is combined with the finite element alternating method. It is found that effects f the residual stresses on the stress intensity factor (SIF) and crack growth rate (CGR) are dominant and values of SIF and CGR of cracks in the region of weld joint are increased by a factor of three or more on an average.

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Analysis of Relationship between Chl-a, COD, and TN, TP in the Agricultural Reservoirs (농업용 저수지에서 Chl-a와 COD, TN, TP 간의 상관관계 분석)

  • Lee, Sae-Bom;Yoon, Chun-Gyeong;Jung, Kwang-Wook;Kim, Hyung-Chul
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2005.10a
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    • pp.626-631
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    • 2005
  • Monitoring data from agricultural reservoirs throughout the country were analyzed to evaluate the limiting factor for algal growth and correlationship between Chl-a, total phosphorus (TP), total nitrogen (TN), and chemical oxygen demand (COD). It was used for the analysis to monitored data of 394 reservoirs such as TP, TN, Chl-a, and COD from 1999 to 2003. This study analyzed water quality items in terms of areas, seasons. It turned out that phosphorus in agricultural reservoirs (about 80%) was dominant limiting factor for algal growth. Therefor, it appears that the appropriate managements of phosphorus in the agricultural watershed are crucial to prevent excessive on algal growth. Generally, there is correlation between Chl-a and TP while Chl-a do not have effect on TN. Also, Chl-a have influence on COD. This study could be used beneficially for water quality management of agricultural reservoirs and related water quality modeling.

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