• Title/Summary/Keyword: D/d ratio

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Market orientation and investment decision of firms (기업의 시장지향성과 투자의사결정)

  • Pyo, Gyungmin
    • Knowledge Management Research
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    • v.20 no.4
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    • pp.119-129
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    • 2019
  • This paper is aim to test how market orientation is related to the investment decision making. After controlling for firm-specific factors, this study finds a significantly positive relationship between market orientation and R&D expenditures, especially firms with high ratio of intangible assets and low ratio of abnormal inventory assets. Under conditions of low quality of earnings, the negative relation between market orientation and R&D expenditures is enhanced in electronic related industries. This indicates that the relation between market orientation and R&D expenditures may exhibit more reasonable patterns for investment decision of firms in technology driven business environment.

Dual-Band Unequal Power Divider based on CRLH Transmission Line (CRLH 전송선로를 기반으로 한 이중대역 비대칭 전력 분배기)

  • Yoo, Jae-Hyun;Kim, Young;Yoon, Young-Chul
    • Journal of Advanced Navigation Technology
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    • v.14 no.6
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    • pp.909-915
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    • 2010
  • In this paper, the unequal power divider based on CRLH (Composite Right/Left-Handed) transmission line with dual-band characteristic is proposed. They consist of dual-band branch line hybrid coupler, the connection between input and isolation port of hybrid coupler and ${\lambda}/4$ impedance transformer. When the transmission line between input and isolation port of hybrid coupler is asymmetrical connected, the divider is obtained the output results of the equal phase and unequal power dividing ratio. The simulation results of the divider represent the power ratio of 0 dB ~ 20 dB. To validate a function of divider, the hybrid coupler and transformer with 880 MHz and 1850 MHz is implemented. As a result, the proposed unequal divider obtains the power ratio of 3.2 dB ~ 8.8 dB at 880 MHz and 2.5 dB ~ 14.0 dB at 1850 MHz.

The Evaluation of TrueX Reconstruction Method in Low Dose (저선량에서의 TrueX 재구성 방법에 의한 유용성 평가)

  • Oh, Se-Moon;Kim, Kye-Hwan;Kim, Seung-Jeong;Lee, Hong-Jae;Kim, Jin-Eui
    • The Korean Journal of Nuclear Medicine Technology
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    • v.15 no.2
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    • pp.83-87
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    • 2011
  • Purpose: Recently in diagnostics area PET/CT is using a variety of areas including oncology, as well as in cardiology, neurology, etc. While increasing in the importance of PET/CT, there are various researches in the image quality related to reconstruction method. We compared and tested Iterative 2D Reconstruction Method with True X Reconstruction method by Siemens through phantom experiment, so we can see increasing of clinical usefulness of PET/CT. Materials and Methods: We measured contrast ratio and FWHM due to evaluating images on dose and experiment using Biograph 40 True Point PET/CT (Siemens, Germany). Getting a result of contrast ratio and FWHM, we used NEMA IEC PET body phantom (Data Spectrum Corp.) and capillary tube. We used the current TrueX and the previous Iterative 2D algorithm for all images which have 10 minutes long. Also, a clinical suitability of parameter for Iterative 2D and a recommended parameter by Siemens for True X are applied to the experiment. Results: We tested FWHM using capillary tube. As a result, TrueX was less than Iterative 2D. Also, the differences of FWHM get bigger in low dose. On the other hand, we tested contrasts ratio using NEMA IEC PET body phantom. As a result, TrueX was better aspect than Iterative 2D. However, there was no difference in dose. Conclusion: In this experiment, TrueX get higher results of contrast ratio and spatial resolution than Itertive 2D through experiment. Also, in the reconstruction result through TrueX, TrueX had better aspect of resolution than Iterative 2D in low dose. However, contrast ratio had no specific difference. In other words, TrueX reconstruction method in PET/CT had higher clinical value in use because TrueX can reduce exposure of patient and had a better quality of screen.

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R&D Investment and Project Performance : Research on Industrial R&D Programs of Government (연구개발투자의 성과에 영향을 미치는 요인에 관한 연구 : 정부의 산업기술개발사업을 중심으로)

  • Chang, Keum-Young
    • Journal of Technology Innovation
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    • v.18 no.1
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    • pp.75-98
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    • 2010
  • The purpose of this paper is to give policy implications for relevant policy-makers by analyzing factors affecting performance of industrial R&D programs of the Ministry of Knowledge Economy. The independent variables are type of project leader organization(Big Enterprises, SMEs, Ventures Businesses, Public Research Institutions, Universities), cooperative or noncooperative R&D among industry-university-research institution, total number of project participant organization, total R&D investment, and the ratio of private investment to total R&D investment. The dependent variables are domestic or foreign patents granted and domestic or foreign papers accepted. The method of analysis is Poisson Regression analysis operated by STATA. The results of this research are follows ; Universities show higher R&D performance compared to enterprises or public research institutions in terms of patents and papers as well. Venture businesses show higher patent performance compared to SMEs. Inverted U-shaped relationship between total number of project participant organization and R&D performance is not supported. The higher total R&D investment, the higher R&D performance. The higher the ratio of private investment to total R&D investment, the higher R&D performance.

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An Experimental Study on the Blocking Performance Considering Construction Joint of Placement (콘크리트 이어붓기 시공에 있어 차단성에 관한 실험적 연구)

  • 김은호;정덕우;한민철;류현기;한천구
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.10a
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    • pp.257-260
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    • 2002
  • This study is intended is to analyze the blocking performance with variation of the gap of bar and kinds of metal lath for construction joint when placing concrete. According to the results, passing ratio of concrete increases with increase of vibrating time. In the case of W/C 50%, when blocking concrete with bar of D10 and D20 which the gap of bar is below 200mm, or metal lath, passing ratio of concrete is below 10%, so blocking performance is favorable. In the case of W/B 30%, while concrete does not flow out without vibration at slump 21mm, concrete flows out at some degree before vibration at slump flow 65mm and then, as 5 seconds passes after first vibration, final passing ratio shows about 85~90%. When blocking concrete by bar D10 of the gap 20mm, bar D20 of the gap 10mm and metal lath, it is thought that concrete can be blocked effectively because final passing ratio is below 10%.

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Performance Analysis of a Hydrodynamic Separator for Treating Particulate Pollutants in Highway Rainfall Runoff

  • Yu, Jianghua;Yi, Qitao;Kim, Young-Chul
    • Environmental Engineering Research
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    • v.14 no.4
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    • pp.262-269
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    • 2009
  • This study examined the separation characteristics of particles in the rainfall runoff from paved roads using a ${\varphi}7.5$ cm hydrocyclone. The volume fraction and total suspended solids concentrations in the overflow and underflow from the hydrocyclone, as well as the separation efficiency were determined. The results indicated that the overflow volume increased with increasing operational pressure, but decreased with decreasing ratio of underflow outlet to inlet sizes ($D_u/D_i$), while the underflow to overflow volumes showed contrary behavior. The total suspended solid (TSS) concentration ratio between the overflow and inflow ($TSS_{over/in}$) decreased as a function of the operational pressure, while the corresponding ratio of underflow to inflow ($TSS_{under/in}$) increased. There was no visible difference in the $TSS_{over/in}$ with increasing $D_u/D_i$ ratio, but the $TSS_{under/in}$ decreased sharply. The particle removal efficiency was mainly affected by the particle size.

The Improvement of Profile Tilt in High Aspect Ratio Contact (컨택 산화막 에칭에서의 바닥 모양 찌그러짐 변형 개선)

  • Hwang, Won-Tae;Choi, Sung-Gil;Kwon, Sang-Dong;Im, Jang-Bin;Jung, Sang-Sup;Park, Young-Wook
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.666-670
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    • 2004
  • VLSI 소자에서 design rule(D/R)이 작아져 각 단위 Pattern의 size가 작아짐에 따라 aspect ratio가 커지게 되었다. 산화막 contact etch를 하는데 있어 산화막 측벽을 보호하는데, 이러한 보호막은 주로 fluoro-carbon 계열의 polymer precursor들이 사용된다. Aspect ratio(A/R)가 5 이하일 때에는 측벽의 보호막에 의한 바닥 변형이 문제가 되지 않으나, 10 이상의 A/R를 가진 contact에서는 크기가 줄고, 모양이 불균형하게 변하는 바닥 변형을 쉴게 관찰할 수 있다. 이러한 바닥 변형이 커지면 contact 저항이 높아지는 것은 물론이고, 심하게는 하부 pattern과 overlap 불량을 유발할 수 있다. 본 논문에서는 바닥변형을 일으키는 원인을 분석하고 fluoro-carbon 계열의 polymer precursor의 종류$(C_4_F6\;vs.\;C_3F_8)$에 따른 polymer증착 상태 확인 및 pattern비대칭에 따른 바닥 변형의 고찰과 plasma etching 시 H/W 변형을 통해 바닥 변형이 거의 없는 조건을 찾아낼 수 있었다.

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The Physical Properties of Filling Batt Using Polyester Yarn (Polyester사를 이용한 충전용 솜사의 물성)

  • Park, Myung-Soo
    • Fashion & Textile Research Journal
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    • v.9 no.3
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    • pp.347-350
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    • 2007
  • To analyse basic properties for making packing batt according to doubling condition, packing batt yarn, of $300^D$, $900^D$, $3600^D$ made from DTY yarn $150^D$/48 were produced from KTDI. The results are as follows: The birefringence of the sample yarn increased with increasing the annealing temperature and denier. The initial modulus of the sample yarn decreased with increasing the annealing temperature and denier. The higher than annealing temperature of $160^{\circ}C$, initial modulus of the sample are equilibrated. The strain recovery ratio of samples decreased with increasing the annealing temperature and denier. The lower than annealing temperature of $140^{\circ}C$, strain recovery ratio of the sample are decreased Where the $900^D$, $3600^D$ yarns are at $100^{\circ}C$ the specific bending rigidity value obtained is 0.65kgf/d but the twisted yarn (3,600) obtained 0.006 ($gfcm^2/tex^2$). However, where the heat temperature is $160^{\circ}C$, specific bending rigidity value obtained 0.003($gfcm^2/tex^2$).

Image quality and usefulness evaluaton of 3D-CBCT and Gated-CBCT according to baseline changes for SBRT of Lung Cancer (폐암 환자의 정위체부방사선치료 시 기준선 변화에 따른 3D-CBCT(Cone Beam Computed-Tomography)와 Gated-CBCT의 영상 품질 및 유용성 평가)

  • Han Kuk Hee;Shin Chung Hun;Lee Chung Hwan;Yoo Soon Mi;Park Ja Ram;Kim Jin Su;Yun In Ha
    • The Journal of Korean Society for Radiation Therapy
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    • v.35
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    • pp.41-51
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    • 2023
  • Purpose: This study compares and analyzes the image quality of 3D-CBCT(Cone Beam Computed-Tomography) and Gated CBCT according to baseline changes during SBRT(Stereotactic Body RadioTherapy) in lung cancer patients to find a useful CBCT method for correcting movement due to breathing Materials and methods : Insert a solid tumor material with a diameter of 3 cm into the QUASARTM phantom. 4-Dimentional Computed-Tomography(4DCT) images were taken with a speed of the phantom at period 3 sec and a maximum amplitude of 20 mm. Using the contouring menu of the computerized treatment planning system EclipseTM Gross Tumor Volume was outlined on solid tumor material. Set-up the same as when acquiring a 4DCT image using Truebeam STxTM, breathing patterns with baseline changes of 1 mm, 3 mm, and 5 mm were input into the phantom to obtain 3D-CBCT (Spotlight, Full) and Gated-CBCT (Spotlight, Full) images five times repeatedly. The acquired images were compared with the Signal-to-Noise Ratio(SNR), Contrast-to-Noise Ratio(CNR), Tumor Volume Length, and Motion Blurring Ratio(MBR) based on the 4DCT image. Results: The average Signal-to-Noise Ratio, Contrast-to-Noise Ratio, Tumor Volume Length and Motion Blurring Ratio of Spotlight Gated CBCT images were 13.30±0.10%, 7.78±0.16%, 3.55±0.17%, 1.18±0.06%. As a result, Spotlight Gated-CBCT images according to baseline change showed better values than Spotligtht 3D-CBCT images. Also, the average Signal-to-Noise Ratio, Contrast-to-Noise Ratio, Tumor Volume Length and Motion Blurring Ratio of Full Gated CBCT images were 12.80±0.11%, 7.60±0.11%, 3.54±0.16%, 1.18±0.05%. As a result Full GatedCBCT images according to baseline change showed better values than Full 3D-CBCT images. Conclusion : Compared to 3D-CBCT images, Gated-CBCT images had better image quality according to the baseline change, and the effect of Motion Blurring Artifacts caused by breathing was small. Therefore, it is considered useful to image guided using Gated-CBCT when a baseline change occurs due to difficulty in regular breathing during SBRT that exposes high doses in a short period of time

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Parametric study on eccentrically-loaded partially encased composite columns under major axis bending

  • Begum, Mahbuba;Driver, Robert G.;Elwi, Alaa E.
    • Steel and Composite Structures
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    • v.19 no.5
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    • pp.1299-1319
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    • 2015
  • This paper presents a detailed parametric study, conducted using finite element tools to cover a range of several geometric and material parameters, on the behaviour of thin-walled partially encased composite (PEC) columns. The PEC columns studied herein are composed of thin-walled built-up H-shaped steel sections with concrete infill cast between the flanges. Transverse links are provided between the opposing flanges to improve resistance to local buckling. The parametric study is confined to eccentrically-loaded columns subjected to major axis bending only. The parameters that were varied include the overall column slenderness ratio (L/d), load eccentricity ratio (e/d), link spacing-to-depth ratio (s/d), flange plate slenderness ratio (b/t) and concrete compressive strength ($f_{cu}$). The overall column slenderness ratio was chosen to be the primary variable with values of 5, 10 and 15. Other parameters were varied within each case of L/d ratio. The effects of the selected parameters on the behaviour of PEC columns were studied with respect to the failure mode, peak axial load, axial load versus average axial strain response, axial load versus lateral displacement response, moment versus lateral displacement behaviour and the axial load-moment interaction diagram. The results of the parametric study are presented in the paper and the influences of each of the parameters investigated are discussed.