• 제목/요약/키워드: small-size

검색결과 9,928건 처리시간 0.04초

Constant-norm Equation-error 적응 IIR 필터를 위한 가변 Step size 알고리즘 (A Variable Step-size Algorithm for Constant-norm Equation-error Adaptive IIR Filters)

  • Kong, Se-Jin;Shin, Hyun-Chool;Song, Woo-Jin
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 제14회 신호처리 합동 학술대회 논문집
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    • pp.91-94
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    • 2001
  • Recently a constant-norm constraint equation-error method was proposed to solve the bias problem in adaptive IIR filtering. However, the method adopts a fixed step-size and thus results in slow convergence for a small step-size and significant misadjustment error for a largestep-size. In this paper, we propose a variable step-size (VSS) algorithm that greatly improves convergence properties of the constant-norm constraint equation-error method. The analysis and the simulation results show that the proposed method indeed achieves both fast convergence and small misadjustment error.

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디젤분무의 벽면충돌거동 및 분무입경측정 (Wall Impingement Behavior and Droplet Size Measurement in Diesel Spray)

  • 이장희;김태권;최인수
    • 한국자동차공학회논문집
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    • 제2권4호
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    • pp.39-49
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    • 1994
  • An experimental investigation was undertaken in a diesel spray to evaluate wall impingement behavior and droplet size distribution. Emphasis is placed on the possibility of the application for new combustion type which is based on OSKA-D type. Visualization were employed using optical scheme which was a spark shadowgraphy to observe the behavior of wall impingement caused by diesel spray vertically injected at the center of the combustion chamber. Droplet size measurements using Malvern system were made to quantify the visual observations with surface diameter of impingement. The effects of the surface dia. variation on the droplet size during injection with the wall impingement spray are discussed. It was found that for the wall impingement spray the droplet size becomes greatly small rather than the spray without the wall impingement and the droplet deposition rate of the injection fuel is decreased as the surface area of impingement becomes small.

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모형 Gabion의 오염물질 포착률 (Model Gabion's Pollutant Accumulation Efficiency)

  • 정재훈;정해원;윤정환;박승기
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2005년도 학술발표논문집
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    • pp.91-96
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    • 2005
  • This study was performed for the research on the method for reducing non-point pollutant with the gabion which was made of gravel-packed plastic frame, and for the characterization of gabion adsorbing pollutant. The result showed that the concentrations of suspended solid in turbid water were reduced to $77.7{\sim}84.7%$ when the water was flowing through the gabion. The uniformity coefficients on the grain size accumulation curves of the adsorbed pollutant were larger on the large grain size gabion than those on the small grain size gabion, and the coefficients of curvature were smaller on the large grain size gabion than those of the small grain size gabion. The adsorption rates were dependent on the grain size of packed gravel. The rates were smaller on inlet and outlet than those on middle place on the series of gabion.

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입자의 크기가 다른 아연공기전지용 아연음극의 부식에 관한 전기화학적 특성 연구 (Electrochemical Properties for the Corrosion of Zinc Anode with Different Particle Size and Shape in Zinc/air Batteries)

  • 양원근;홍정의;오례경;오지우;공영민;류광선
    • 한국분말재료학회지
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    • 제20권3호
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    • pp.186-190
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    • 2013
  • The electrochemical performance for the corrosion of zinc anodes according to particle size and shape as anode in Zn/air batteries was study. We prepared five samples of Zn powder with different particle size and morphology. For analysis the particle size of theme, we measured particle size analysis (PSA). As the result, sample (e) had smaller particle size with $10.334{\mu}m$ than others. For measuring the electrochemical performance of them, we measured the cyclic voltammetry and linear polarization in three electrode system (half-cell). For measuring the morphology change of them before and after cyclic voltammetry, we measured Field Emission Scanning Electron Microscope (FE-SEM). From the cyclic voltammetry, as the zinc powder had small size, we knew that it had large diffusion coefficient. From the linear polarization, as the zinc powder had small size, it was a good state with high polarization resistance as anode in Zn/air batteries. From the SEM images, the particle size had increased due to the dendrite formation after cyclic voltammetry. Therefore, the sample (e) with small size would have the best electrochemical performance between these samples.

골프장 조성이 소유역의 지형적 특성에 미치는 영향 분석 (The Effects of Golf Course Construction on the Geomorphic Characteristics of a Small Watershed)

    • 한국조경학회지
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    • 제27권2호
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    • pp.41-50
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    • 1999
  • The purpose of this study is to find out the changes in geomorphic characteristics of a small watershed when a golf course is constructed. The research site is a set of seven small watersheds including an 18-hole golf course that were randomly selected. The size, shape, and drainage network of watersheds were measured by using planimeter, watershed eccentricity, and stream order, respectively. In addition, a 25m$\times$25m mesh was used on topographic maps and grading plans in order to obtain the slope, elevation, and aspect of the watersheds. The major results of this research, while investigating of the changes in geomorphic characteristics of watersheds when a golf course is constructed, are as follows: 1. The size of watersheds is increased in accordance to the difference in elevation between the golf course site and the small watershed. 2. The watershed eccentricities are in general similar except for a few low-valued cases. 3. The changes in the average altitude and the gradient are more drastic with their bigger original values. 4. The aspects are changed more with decreasing elevation. 5. The stream order decreases in the case of a low watershed eccentricity. 6. The surface modification has a closer relationship to the slope rather than the size of effective use area. 7. With a steeper gradient and an excessively low gradient, the height of cutting/filling is increased.

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중소기업의 기술혁신 지원을 위한 전문가(Project-Specialist)제도 도입 방안 (An Adaption on the Project-Specialist System for the Small and Medium If enterprises)

  • 김윤호
    • 한국정보통신학회논문지
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    • 제8권7호
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    • pp.1565-1569
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    • 2004
  • IT중소기업(Small and Medium-size Enterprises)의 기술개발은 대학, 출연연구소 및 대기업의 기술 개발과는 달리 인력, 재원, 규모 둥에서 환경이 매우 열악하다. 중소기업들이 열악한 환경은 정부가 지원하는 기술개발 출연사업에 대한 과열경쟁을 불러오고, 기술개발 규모는 과제당 3억원 내외로 적은 예산을 다수의 기업에 나누어 지원하는 현상이 발생하고 있다. 다수 소액과제를 지원관리하면서 연구개발 내용보다는 기업의 부실화 둥 기술개발 외적인 관리에 치중하게 된다. 따라서 실태조사 등 불필요한 현장 감사가 진행될 수밖에 없는데, 감독목적의 실태조사보다 기술개발을 주관하는 중소기업의 기술애로 해소 및 상업화 등 노하우 지원이 시급한 실정이다. 따라서 중소기업의 실질적인 기술개발 지원을 위해서 대학이나 연구소 등에 근무하는 기술개발 및 상용화 전문가들을 중소기업의 기술개발 지원 전문가로 활용하는 방안을 제안한다.

Treatment Results of Small Intestinal Gastrointestinal Stromal Tumors Less than 10 cm in Diameter: A Comparison between Laparoscopy and Open Surgery

  • Ihn, Kyong;Hyung, Woo Jin;Kim, Hyoung-Il;An, Ji Yeong;Kim, Jong Won;Cheong, Jae-Ho;Yoon, Dong Sup;Choi, Seung Ho;Noh, Sung Hoon
    • Journal of Gastric Cancer
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    • 제12권4호
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    • pp.243-248
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    • 2012
  • Purpose: To evaluate the technical feasibility and oncologic safety, we assessed the short-term and long-term outcomes of laparoscopic resection of the small bowel gastrointestinal stromal tumors smaller than 5 cm by comparing those of open surgery by subgroup analysis based on tumor size. Materials and Methods: From November 1993 to January 2011, 41 laparoscopic resections were performed among the 95 patients who underwent resection of small intestine ${\leq}10$ cm in diameter. The clinicopathologic features, perioperative outcomes, recurrences and survival of these patients were reviewed. Results: The postoperative morbidity rates were comparable between the 2 groups. Laparoscopic surgery group showed significantly shorter operative time (P=0.004) and duration of postoperative hospital stay (P<0.001) than open surgery group and it was more apparent in the smaller tumor size group. There were no difference in 5-year survival for the laparoscopic surgery versus open surgery groups (P=0.163), and in 5-year recurrence-free survival (P=0.262). The subgroup analysis by 5 cm in tumor size also shows no remarkable differences in 5-year survival and recurrence-free survival. Conclusions: Laparoscopic resection for small bowel gastrointestinal stromal tumors of size less than 10 cm has favorable short-term postoperative outcomes, while achieving comparable oncologic results compared with open surgery. Thus, laparoscopic approach can be recommended as a treatment modality for patients with small bowel gastrointestinal stromal tumors less than 10 cm in diameter.

Genetics, Agronomic, and Molecular Study of Leaflet Mutants in Mungbean(Vigna radiata(L.) Wilczek)

  • Soehendi, Rudy;Chanprame, Sontichai;Toojinda, Theerayut;Ngampongsai, Sumana;Srinives, Peerasak
    • Journal of Crop Science and Biotechnology
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    • 제10권3호
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    • pp.193-200
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    • 2007
  • Mungbean plants generally have a relatively close canopy, thus a large amount of self-shading can reduce yield due to poor light penetration. Modification of leaflet type can affect leaf canopy and could alter seed yield. Two multiple leaflet mutants were obtained from gamma-ray irradiation and used to study the mode of inheritance related to leaflet types and to evaluate their agronomic features. The cross between large-heptafoliate leaflet with small-pentafoliate leaflet mutants produce all $F_1$ plants with normal trifoliate leaflets. The $F_2$ plants segregated in leaflet size and leaflet number into a 9:3:3:1 ratio of large-trifoliate: large-heptafoliate: small-pentafoliate: small-heptafoliate plants, suggesting that independent loci control leaflet size and leaflet number. Regarding leaflet number, the $F_2$ population can be classified into normal-trifoliate, small-pentafoliate, large-heptafoliate, and small-heptafoliate at the dihybrid ratio of 9:3:3:1. The gene symbols $N_1,n_1$ and $N_2,n_2$ are proposed to represent leaflet number. Since no plant was found with large-pentafoliate leaflets, we hypothesize that the $N_2$ allele expresses pleiotropic effect on both leaflet number and leaflet size. Another possibility is that an additional locus with S and s alleles controls leaflet size and S is tightly linked with $N_2$. The effect of multifoliate leaflet on yield and yield components was evaluated in four mungbean families each with four leaflet isolines under three environments. Averaging across the families and environments, the normal-trifoliate and large-heptafoliate lines gave higher yield than small pentafoliate and heptafoliate ones. These two large leaflet lines also had higher leaf area per plant than the other multifoliate lines. Therefore, the mungbean lines with a greater leaf area, which were likely to intercept more sunlight, gave greater yield. Three AFLP markers that were found to be linked to number of leaflets per leaf, corresponded to the N1 allele of the smallpentafoliate parent.

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TOE 프레임워크를 활용한 RPA 도입 의도에 미치는 영향 요인 연구 - 중소기업 규모의 조절효과를 중심으로 - (A Study on Factors Affecting the Degree of RPA Patching Using the TOE Framework - Focusing on the Effect of Adjusting the Size of Small and Medium-sized Businesses -)

  • 곽영기;이원부
    • 품질경영학회지
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    • 제52권1호
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    • pp.149-172
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    • 2024
  • Purpose: By empirically analyzing factors that affect the intention to introduce RPA, we aim to increase understanding of RPA introduction in small and medium-sized businesses and contribute to establishing an effective introduction strategy. The aim is to improve the company's productivity, reduce costs, and strengthen its competitiveness. It also provides policy recommendations for the introduction of RPA. Methods: A survey was conducted to examine whether the technical, organizational, and environmental factors of the TOE framework had an impact on the intention to adopt RPA. We also used stepwise regression analysis to determine whether firm size moderates this relationship. Results: Technical factors, organizational factors, and environmental factors were all found to have a significant impact on small and medium-sized enterprises' intention to adopt RPA. It was confirmed that company size has a moderating effect affecting the intention to adopt RPA. In particular, customer pressure, relative advantage, competitive pressure, age, government support, and the perceived ease of use of RPA was a key determinant of its adoption by small and medium-sized enterprises. Conclusion: This suggests that small and medium-sized businesses should comprehensively consider technical, organizational, and environmental factors when introducing RPA. It is expected to increase understanding of RPA introduction in small and medium-sized businesses, contribute to establishing effective introduction strategies, and contribute to improving company productivity, reducing costs, and strengthening competitiveness.

소형 머신 비전 검사 장비에 기반한 O링 치수 측정 (O-ring Size Measurement Based on a Small Machine Vision Inspection Equipment)

  • 정유수;박길흠
    • 한국산업정보학회논문지
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    • 제19권4호
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    • pp.41-52
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    • 2014
  • 본 논문은 O링의 치수 측정에 있어 고가의 대 중형 머신비전 장비를 대체할 수 있는 소형 머신 비전 검사 장비에 기반한 O링 부품 내 외경 측정 알고리즘을 제안한다. 백라이트 조명하에 하나의 CCD 카메라를 이용하여 측정 평면으로 부터 영상을 획득하는 소형 머신 비전 검사장비에 의해 획득된 영상을 제안한 영상처리 기법 알고리즘을 이용하여 O링의 외경 및 내경치수를 측정한다. 치수 측정의 정확도를 높이기 위해 렌즈계 왜곡 보정과 원근 왜곡 보정을 소프트웨어적 기법으로 보정 하였고 O링 형상을 고려하여 타원정합 모델을 적용하였으며 보다 타원 정합의 신뢰성을 높이기 위해 RANSAC알고리즘을 적용하였다.