• Title/Summary/Keyword: Shadow effect

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Fabrication of electrodes on mcirochannel side wall using shadow evaporation effect (샤도우 증착 효과를 이용한 마이크로 채널내 측벽 전극 제작)

  • 강길환;김규만
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.1462-1465
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    • 2004
  • A new method to fabricate metal electrodes on side wall of the microchannel is presented. Coulter counter allows to count the number of cell passing through the microchannel by detecting impedance variation between two electrodes. The relative position of two electrodes is important for sensitivity of impedance measurement. 100nm thick Al electrodes are deposited on the channel side wall by means of shadow evaporation.

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Shadow Economy, Corruption and Economic Growth: An Analysis of BRICS Countries

  • NGUYEN, Diep Van;DUONG, My Tien Ha
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.4
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    • pp.665-672
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    • 2021
  • The paper examines the impact of shadow economy and corruption, along with public expenditure, trade openness, foreign direct investment (FDI), inflation, and tax revenue on the economic growth of the BRICS countries. Data were collected from the World Bank, Transparency International, and Heritage Foundation over the 1991-2017 period. The Bayesian linear regression method is used to examine whether shadow economy, corruption and other indicators affect the economic growth of countries studied. This paper applies the normal prior suggested by Lemoine (2019) while the posterior distribution is simulated using Monte Carlo Markov Chain (MCMC) technique through the Gibbs sampling algorithm. The results indicate that public expenditure and trade openness can enhance the BRICS countries' economic growth, with the positive impact probability of 75.69% and 67.11%, respectively. Also, FDI, inflation, and tax revenue positively affect this growth, though the probability of positive effect is ambiguous, ranging from 51.13% to 56.36%. Further, the research's major finding is that shadow economy and control of corruption have a positive effect on the economic growth of the BRICS countries. Nevertheless, the posterior probabilities of these two factors are 62.23% and 65.25%, respectively. This result suggests that their positive effect probability is not high.

Analysis of Hydraulic Fracture Geometry by Considering Stress Shadow Effect during Multi-stage Hydraulic Fracturing in Shale Formation (셰일저류층의 다단계 수압파쇄에서 응력그림자 효과를 고려한 균열형태 분석)

  • Yoo, Jeong-min;Park, Hyemin;Wang, Jihoon;Sung, Wonmo
    • Journal of the Korean Institute of Gas
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    • v.25 no.1
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    • pp.20-29
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    • 2021
  • During multi-stage fracturing in a low permeable shale formation, stress interference occurs between the stages which is called the "stress shadow effect(SSE)". The effect may alter the fracture propagation direction and induce ununiform geometry. In this study, the stress shadow effect on the hydraulic fracture geometry and the well productivity were investigated by the commercial full-3D fracture model, GOHFER. In a homogeneous reservoir model, a multi-stage fracturing process was performed with or without the SSE. In addition, the fracturing was performed on two shale reservoirs with different geomechanical properties(Young's modulus and Poisson's ratio) to analyze the stress shadow effect. In the simulation results, the stress change caused by the fracture created in the previous stage switched the maximum/minimum horizontal stress and the lower productivity L-direction fracture was more dominating over the T-direction fracture. Since the Marcellus shale is more brittle than more dominating over the T-direction fracture. Since the Marcellus shale is more brittle than the relatively ductile Eagle Ford shale, the fracture width in the former was developed thicker, resulting in the larger fracture volume. And the Marcellus shale's Young's modulus is low, the stress effect is less significant than the Eagle Ford shale in the stage 2. The stress shadow effect strongly depends on not only the spacing between fractures but also the geomechanical properties. Therefore, the stress shadow effect needs to be taken into account for more accurate analysis of the fracture geometry and for more reliable prediction of the well productivity.

Definition and Analysis of Shadow Features for Shadow Detection in Single Natural Image (단일 자연 영상에서 그림자 검출을 위한 그림자 특징 요소들의 정의와 분석)

  • Park, Ki Hong;Lee, Yang Sun
    • Journal of Digital Contents Society
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    • v.19 no.1
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    • pp.165-171
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    • 2018
  • Shadow is a physical phenomenon observed in natural scenes and has a negative effect on various image processing systems such as intelligent video surveillance, traffic surveillance and aerial imagery analysis. Therefore, shadow detection should be considered as a preprocessing process in all areas of computer vision. In this paper, we define and analyze various feature elements for shadow detection in a single natural image that does not require a reference image. The shadow elements describe the intensity, chromaticity, illuminant-invariant, color invariance, and entropy image, which indicate the uncertainty of the information. The results show that the chromaticity and illuminant-invariant images are effective for shadow detection. In the future, we will define a fusion map of various shadow feature elements, and continue to study shadow detection that can adapt to various lighting levels, and shadow removal using chromaticity and illuminance invariant images.

Analysis of Shadow Effect on High Resolution Satellite Image Matching in Urban Area (도심지역의 고해상도 위성영상 정합에 대한 그림자 영향 분석)

  • Yeom, Jun Ho;Han, You Kyung;Kim, Yong Il
    • Journal of Korean Society for Geospatial Information Science
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    • v.21 no.2
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    • pp.93-98
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    • 2013
  • Multi-temporal high resolution satellite images are essential data for efficient city analysis and monitoring. Yet even when acquired from the same location, identical sensors as well as different sensors, these multi-temporal images have a geometric inconsistency. Matching points between images, therefore, must be extracted to match the images. With images of an urban area, however, it is difficult to extract matching points accurately because buildings, trees, bridges, and other artificial objects cause shadows over a wide area, which have different intensities and directions in multi-temporal images. In this study, we analyze a shadow effect on image matching of high resolution satellite images in urban area using Scale-Invariant Feature Transform(SIFT), the representative matching points extraction method, and automatic shadow extraction method. The shadow segments are extracted using spatial and spectral attributes derived from the image segmentation. Also, we consider information of shadow adjacency with the building edge buffer. SIFT matching points extracted from shadow segments are eliminated from matching point pairs and then image matching is performed. Finally, we evaluate the quality of matching points and image matching results, visually and quantitatively, for the analysis of shadow effect on image matching of high resolution satellite image.

Effect of Heat Treatment Process on the Shadow Mask Tension (세도우 마스크 장력에 열공정이 미치는 영향)

  • 현도익;문영훈;조종래
    • Transactions of Materials Processing
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    • v.12 no.5
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    • pp.487-492
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    • 2003
  • Tension variations with heat treatment in shadow mask for flat braun tubes are investigated in this study. In CRT, landing shift of the electron beam due to thermal deformation of the tension mask made the color purity of screen worse. In order to get the final results of thermal deformation, the tensile force within the mask and the welding processes between the rail and the extended mask have to be analysed sequentially. In this study, the effect of heat treatment is studied in terms of tension variations of shadow mask during its manufacturing process.

Numerical Study of Shadow Effect on Slab Deformation in Reheating Furnace (균열로의 그늘효과에 의한 슬랩변형에 관한 수치해석적 연구)

  • Noh, J.H.;Hwang, B.B.;Maeng, J.W.;Kim, J.D.
    • Transactions of Materials Processing
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    • v.20 no.2
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    • pp.132-139
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    • 2011
  • Three dimensional simulations were performed for the deformation of a slab in a roller hearth type slab reheating furnace. The main objective of this study was to examine the deformation pattern of the slab due to the shadow effect, i.e., the temperature difference between the upper and lower slab surfaces, in particular, the variations of displacement and effective stress in the vertical direction. A commercially available FE code, ANSYS Workbench $12.1^{TM}$, was used in a fully coupled thermo-elasticity analysis. Several cases with different slab surface temperatures were selected for the simulations. For the sake of simplicity, the temperature environment inside the furnace was assumed to be homogeneous for the upper and lower faces of the slab. Two cases of with different slab width were selected as model geometry. The deformation patterns were computed and explained in terms of periodicity and symmetry. The results indicated that the shadow effect leads to a significant displacement in the vertical direction and, thereby, is one of the main reasons for the separation of the slab and its supports. These simulations also predicted that the deformation is more severe along the transverse direction than along the longitudinal direction.

Kiosk Use Among Seniors: An Empirical Investigation of the Effects of Technostress and Subjective Norms on Awareness of Shadow Work (고령층의 키오스크 사용에서의 기술스트레스와 주관적 규범이 그림자노동 지각에 미치는 영향: 실증 분석)

  • Ji, Do-Sung;Koh, Joon
    • Informatization Policy
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    • v.30 no.4
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    • pp.62-88
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    • 2023
  • While the introduction of kiosk has become an essential element, enjoying the effect of labor cost reduction, it has not been able to embrace the senior population due to the digital divide. This study investigated which factors have relationships with conflict over use for kiosk from the viewpoint of shadow work that appears during self-service kiosk use. An analysis of 159 seniors through survey revealed that both technostress and subjective norms had significant relationships with conflict over use for kiosk, and that the perception of shadow work had a partial mediating effect on these relationships. Further, user experience showed a moderating effect on the relationship between technostress and perception of shadow work. These results suggest theoretical and practical implications related to digital shadow work, providing the relevant policy regarding digital inclusion for seniors.

THE EFFECTS OF DIFFERENT SHADING OF MULCHING ON YIELD OF ROOT AND QUALITY IN PANAX GINSENG

  • Yang Yeong-yuh
    • Proceedings of the Ginseng society Conference
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    • 1974.09a
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    • pp.137-146
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    • 1974
  • This experiment was on the purpose to study the effects of different shading of Mulching treatments on the quality and yield of ginseng root. This experiment were conducted at Mei-Feng for one year, from July, 1972 to July, 1973. The variety been used was introduced Korea Panax ginsvng. Three different Shading of Mulching treatments have been studied. The results were summerized as follows: 1. The growth of ginseng plant is good under around 4,300 Lux of light intensity. Fig . showed the shadow treatment of straw had a better effect than that of black or grey plastic film. The differences between treatments were significant. 2. The adequate soil temperature for ginseng culture was in the range of $16-18^{\circ}C$. Fig 2. showed that there were significant differences among treatments, of which the straw shadow treatment had the best effect. 3. The growth of ginseng plant was greatly affected wth various shadow treatments. Fig 1. showed both straw and black plastic film treatments had a better effects on growth of stem, leaf area and leaf numbers. 4. Fig. 2. 3. 4. 5 indicated there were distingished differences among all treatments. The straw and black plastics film mulching treatments had a better effects on root length, root diameter, root weight and leaf weight than the grey plastic film. 5. The amount of plant alkaloids and panacene content had related to the shadow treatment, as showed in Fig. 6 and 7 that straw shadow treatment had greatly increased the procuction of plant alkaloids and panacene content. 6. The quality and yield of roots of ginseng greatly affected by different shading of mulching treatments.

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A Novel MPPT Control of PV MIC System Considering the Shaded Effect (그림자 영향을 고려한 PV MIC 시스템의 새로운 MPPT 제어)

  • Choi, Jung-Sik;Chung, Dong-Hwa
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.5
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    • pp.21-33
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    • 2012
  • This paper presents the new maximum power point tracking(MPPT) control of the photovoltaic(PV) module integrated converter(MIC) system considering the shadow influence. The output characteristics of the solar cell is a nonlinear and affected by a temperature, the solar radiation and influence of a shadow. Particularly, MIC system is very sensitive to the shadow influence because the capacity is very small. In order to increase an output and efficiency of the solar power generation, the maximum power point(MPP) obeying control are necessary. Conventional perturbation and observation(PO) and Incremental conductance(IC) are the method finding MPP by the continued self-excitation vibration. The MPPT control is unable to be performed by rapid output change affected by the shadow. To solve this problem, the new control algorithm of the multi-level in which the step value changes by output change is presented. In case there are the solar radiation, a temperature and shadow influence, the presented algorithm treats and compares the conventional control algorithm and output error. In addition, the validity of the algorithm is proved. through the output error response characteristics.