• Title/Summary/Keyword: asymmetric structure

Search Result 583, Processing Time 0.026 seconds

Tomographic reconstruction of Asymmetric Spray by Direct Sampling Method (직접샘플링에 의한 비대칭 분무의 토모그래피 재구성)

  • Lee, C.H.;Won, J.C.
    • Journal of ILASS-Korea
    • /
    • v.7 no.4
    • /
    • pp.9-15
    • /
    • 2002
  • Convolution Fourier transformation tomographically reconstructs the spatially resolved spray injection rate from direct measuring cells. Asymmetric sprays generated from a twin-hole air shroud injector are tested with 12 equiangular projections of measurements. For each projection angle, line of sight integrated injection rate was measured at 35 positions with equal spacing measuring cells of 3 mm in width, 100 mm in length, 55 mm in depth and 0.5 mm thickness of separating wall. Interpolated data between the projection angles effectively increase the number of projections, which significantly enhances the signal-to-noise level in the reconstructed data. This modified convolution Fourier transformation scheme predicts well the structure of asymmetric sprays. Comparative study has been made between sprays with and without air shrouding. Tomograhpic reconstruction of injection rate from direct measuring cells obtained can be used to estimate the accuracy of volume fraction of spray from the LDPA tomographic reconstruction.

  • PDF

A Study on Partially-Depleted SOI MOSFET with Multi-gate (다중 게이트을 이용한 부분 공핍형 SOI MOSFET 특성에 관한 연구)

  • Shin, K.S.;Park, Y.K.;Lee, S.J.;Kim, C.J.
    • Proceedings of the KIEE Conference
    • /
    • 1997.07d
    • /
    • pp.1286-1288
    • /
    • 1997
  • In this study, partially-depleted SOI MOSFET with multi-gate was fabricated on p-type SIMOX(Seperation by Implanted Oxygen). As increase the number of its gate, increase the breakdown voltage. But kink effect was not affected by the number of its gate. However, it is known that the asymmetric gate structure reduce kink effect. So if asymmetric multi-gate applied to partially-depleted SOI MOSFET, it is expected that the breakdown voltage of SOI MOSET with asymmetric multi-gate is higher than that of SOI MOSFET with single gate and that kink effect is reduced by SOI MOSFET with asymmetric multi-gate.

  • PDF

Pyramidal Business Groups and Asymmetric Financial Frictions

  • CHO, DUKSANG
    • KDI Journal of Economic Policy
    • /
    • v.41 no.3
    • /
    • pp.1-38
    • /
    • 2019
  • Given capital market imperfections, an entrepreneur can alleviate financial frictions by creating a pyramidal business group in which a parent firm offers its subsidiary firm internal finance. This endogenous creation of pyramidal business groups can beget asymmetric financial frictions between business-group firms and stand-alone firms. I build a model to show that these asymmetric financial frictions can have sizable effects on resource allocation. On one hand, the financial advantage of pyramidal business groups can foster productive firms by incorporating them as subsidiaries. On the other hand, the asymmetrically large amount of external capital controlled by pyramidal business groups can be expended by unproductive business-group firms and push up the equilibrium price of capital. The model suggests that with fine investor protection or low financial frictions, the benefits of pyramidal business groups can be dominated by their costs because the probability of fostering productive subsidiaries diminishes as the efficiency of external capital markets improves, while the prevalence of pyramidal business groups is not attenuated due to their continuing asymmetric financial advantage.

Long-Range Surface Plasmon-Polariton Wavelength Filter based on Asymmetric Double-Electrode Structure (비대칭 이중-금속 장거리 표면-플라즈몬 도파로를 이용한 파장필터)

  • Shim, Yu-Tae;Joo, Yang-Hyun;Song, Seok-Ho
    • Korean Journal of Optics and Photonics
    • /
    • v.19 no.6
    • /
    • pp.429-434
    • /
    • 2008
  • We propose a wavelength filter based on long-range surface plasmon-polaritons (LR-SPP) supported by a asymmetric doubleelectrode LR-SPP structure. For the case of the asymmetric double-layered LR-SPP waveguide, LR-SPPs exist with a much broader range of index mismatches between core and clad materials. Thus, the asymmetric double-electrode LR-SPP waveguide is adequate to form a plasmonic band-gap device as we report in this paper by studying Bragg-reflection wavelength filter based on it. The structure for wavelength filter operating telecommunications wavelength is designed by using the method of line (MoL) and the transfer matrix method. The fabricated device shows a relatively high extinction ratio of 50 dB with a bandwidth of 2 nm, and the performance is very consistent with numerical simulations.

Pervaporation Separation of Water-isopropanol Mixtures through Modified Asymmetric Polyetherimide Membrane: the Effect of NaOH Concentration and Modification Reaction Times on the Morphology of the Morphology of the Modified Membranes (개질 비대칭 폴리에테르이미드막을 통한 물-이소프로판올 혼합물 투과증발 분리: NaOH용액의 농도와 개질반응 시간에 따른 몰폴로지 변화)

  • Kim, Sang-Gyun;Jegal, Jonggeon;Lee, Kew-Ho
    • Applied Chemistry for Engineering
    • /
    • v.10 no.4
    • /
    • pp.515-522
    • /
    • 1999
  • Asymmetric polyetherimide membrane were prepared by phase inversion method, and the effects of NaOH concentration and reaction time on the morphology change of the polyetherimide membranes were studied. The morphology of skin layers varied from dense structure to sphere structure with increasing concentration of modification solution. The thickness of dense layer increased with increasing reaction time. However, when either the concentration of modifying solution was very high or the reaction time was very long, the dense layers of the asymmetric membrane were disappeared. From these results, it was found that the surface morphology of the asymmetric polyetherimide membranes depended strongly on the modification conditions such as concentration of modification solution and reaction time. These results might be explained by the hydrolysis reaction of polyetherimide into polyamic acid by the NaOH solution.

  • PDF

Analysis of Threshold Voltage for Symmetric and Asymmetric Oxide Structure of Double Gate MOSFET (이중게이트 MOSFET의 대칭 및 비대칭 산화막 구조에 대한 문턱전압 분석)

  • Jung, Hakkee
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.18 no.12
    • /
    • pp.2939-2945
    • /
    • 2014
  • This paper has analyzed the change of threshold voltage for oxide structure of symmetric and asymmetric double gate(DG) MOSFET. The asymmetric DGMOSFET can be fabricated with different top and bottom gate oxide thickness, while the symmetric DGMOSFET has the same top and bottom gate oxide thickness. Therefore optimum threshold voltage is considered for top and bottom gate oxide thickness of asymmetric DGMOSFET, compared with the threshold voltage of symmetric DGMOSFET. To obtain the threshold voltage, the analytical potential distribution is derived from Possion's equation, and Gaussian distribution function is used as doping profile. We investigate for bottom gate voltage, channel length and thickness, and doping concentration how top and bottom gate oxide thickness influences on threshold voltage using this threshold voltage model. As a result, threshold voltage is greatly changed for oxide thickness, and we know the changing trend greatly differs with bottom gate voltage, channel length and thickness, and doping concentration.

An Experimental Study on Blasting Collapse Behavior of Asymmetry Structure with High Aspect Ratio (고종횡비 비대칭 구조물의 발파붕괴 거동에 관한 연구)

  • Song, Young-Suk;Jung, Min-Su;Jung, Dong-Wol;Hur, Won-Ho
    • Explosives and Blasting
    • /
    • v.31 no.1
    • /
    • pp.1-10
    • /
    • 2013
  • In blasting demolition, a method would be chosen among many depends on shape and system of a structure and its surround. To demolish using explosives a structure, which is asymmetric and with high aspect ratio, pre-weakening, explosive locations, detonating delay, and surround conditions are needed to be considered in front to design blasting demolition plan. In this study, to over turn asymmetric and high aspect ratio structure in safe, a simulation using a software named Extreme Loadings for Structures, ELS, had performed. In results, it is achieved optimized pre-weakening shapes and locations, which prevent kick back motion of the structure when it collapse, by analyzing moment distribution caused by pre-weakening. And of structural collapse and by minimizing asymmetric structure's torsional moment. Also, after the demolition, simulation results are also compared with actual collapse behavior. In results, it is confirmed the accuracy of collapse behaviour simulation results, and in blasting demolition, kick back motion can be controled by adjusting pre-weakening shape and location, and the torsional moment of an asymmetric structure also can be solved by optimizing detonation locations and its time intervals.

Asymmetric Impact of IS Quality on User Satisfaction: Development of Resource Allocation Strategy of e-Government in Agriculture

  • Park, Heun Dong;Kim, Haneul
    • Agribusiness and Information Management
    • /
    • v.5 no.1
    • /
    • pp.42-54
    • /
    • 2013
  • Information System (IS) Success Model proposed by DeLone and McLean is applied as a successful operation tool of information system, with its basic assumption of symmetric relationship between independent variables and dependent variables of the structural equation modeling. However, because previous studies have proved asymmetry of quality factors' influence structure on dependent variable by applying three-factor analysis, this study examined asymmetry of impact structure of quality factors introduced in IS Success Model on user satisfaction. Also the study applies structure equation modeling (SEM), three-factor analysis and importance and performance analysis (IPA) to develop resource allocation strategy for IS success. The study is able to provide IS practitioners with strategic implications for allocating and managing limited resources more effectively.

  • PDF

Design and Experimental Verification of Two Dimensional Asymmetric Supersonic Nozzle (이차원 비대칭형 초음속 노즐 설계와 실험적 검증)

  • Kim, Chae-Hyoung;Sung, Kun-Min;Jeung, In-Seuck;Choi, Byoung-Il;Kouchi, Toshinori;Masuya, Goro
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.37 no.9
    • /
    • pp.899-905
    • /
    • 2009
  • Most supersonic-flow test facility has axisymmetric nozzles or two-dimensional symmetric nozzles. Compared to these nozzles, a two-dimensional asymmetric nozzle has advantages of reducing low cost for various Mach number testing and undesirable flow structure such as shock wave reflection because the nozzle part can be directly connected to the test section part in this type of nozzle. The two-dimensional asymmetric nozzle, which was Mach number 2, was designed for supersonic combustion experiment. And it was verified with the numerical analysis and visualization of Mach wave. This study suggested the practical method for design and verification of supersonic two dimensional asymmetric nozzles.

Asymmetric Transmission between Producer and Wholesale Prices in Farmed Olive Flounder Market (양식넙치 산지-도매가격간 비대칭적 가격전이 분석)

  • Lee, Heon-Dong;Ma, Chang-Mo
    • The Journal of Fisheries Business Administration
    • /
    • v.51 no.4
    • /
    • pp.69-83
    • /
    • 2020
  • The purpose of this paper is to empirically investigate whether asymmetric price transmission exists in the distribution stage of farmed olive flounder market. For the analysis, time series data were used for the producer prices of Jeju and Wando, and the wholesale prices of Incheon, Hanam and Busan. Through the Granger causality test, the causal relationship from the producer price to the wholesale price was derived and the asymmetric price transmission was analyzed using the autoregressive distributed lag model (ARDL). As a result of the analysis, it was found that there is a phenomenon of 'positive asymmetric price transmission' from the producer price to the wholesale price. This result can be one evidence that excess profits are received in the intermediate distribution stage, and can be said to be a result showing the incompleteness and inefficiency of the distribution structure of the farmed olive flounder. In the future, it is required to establish an information-sharing system in all stages of production, distribution, and consumption that can create a competitive environment for distribution participants and resolve information asymmetry. Also, it is necessary to review the distribution center specializing in live fish from the viewpoint of the establishment of new distribution channels and sales diversification strategy under the rapidly changing fisheries environment.