• Title/Summary/Keyword: ghost point

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3D Panoramic Mosaiciking to Silppress the Ghost Effect at Long Distance Scene for Urban Area Visualization (도심영상 입체 가시화 중 발생하는 원거리 환영현상 해소를 위한 3차원 파노라믹 모자이크)

  • Chon, Jae-Choon;Kim, Hyong-Suk
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.4 s.304
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    • pp.87-94
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    • 2005
  • 3D image mosaicking is useful for 3D visualization of the roadside scene of urban area by projecting 2D images to the 3D planes. When a sequence of images are filmed from a side-looking video camera passing long distance areas, the ghost effect in which same objects appear repeatively occurs. To suppress such ghost effect, the long distance range areas are detected by using the distance between the image frame and the 3D coordinate of tracked optical flows. The ghost effects are suppressed by projecting the part of image frames onto 3D multiple planes utilizing vectors passing the focal point of frames and a virtual focal point. The virtual focal point is calculated by utilizing the first and last frames of the long distance range areas. We demonstrate algorithm that creates efficient 3D Panoramic mosaics without the ghost effect at the long distance area.

CKGS: A Way Of Compressed Key Guessing Space to Reduce Ghost Peaks

  • Li, Di;Li, Lang;Ou, Yu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.3
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    • pp.1047-1062
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    • 2022
  • Differential power analysis (DPA) is disturbed by ghost peaks. There is a phenomenon that the mean absolute difference (MAD) value of the wrong key is higher than the correct key. We propose a compressed key guessing space (CKGS) scheme to solve this problem and analyze the AES algorithm. The DPA based on this scheme is named CKGS-DPA. Unlike traditional DPA, the CKGS-DPA uses two power leakage points for a combined attack. The first power leakage point is used to determine the key candidate interval, and the second is used for the final attack. First, we study the law of MAD values distribution when the attack point is AddRoundKey and explain why this point is not suitable for DPA. According to this law, we modify the selection function to change the distribution of MAD values. Then a key-related value screening algorithm is proposed to obtain key information. Finally, we construct two key candidate intervals of size 16 and reduce the key guessing space of the SubBytes attack from 256 to 32. Simulation experimental results show that CKGS-DPA reduces the power traces demand by 25% compared with DPA. Experiments performed on the ASCAD dataset show that CKGS-DPA reduces the power traces demand by at least 41% compared with DPA.

Composition of Marine Organisms Caught from Lost Plastic Pot and Possibility of Sustainable Ghost Fishing (유실된 플라스틱 붕장어 통발에 어획된 해양 생물의 종류와 지속적인 Ghost Fishing의 가능성)

  • Jeong, Sun-Beom
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.40 no.1
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    • pp.60-64
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    • 2004
  • The reason of the loss for the plastic sea-eel pots were estimated as crew's mistake, strong current, bad weather, rough seabed, artificial reef and other boats' fishing. Especially, pot loss happened on the fishing could make some additional catch, loss of the catches and ghost fishing because there are baits and alive fish in the lost pot. Quantity of the lost pots was estimated as 2~4 times of the ordinary usage. On the result of investigation to analyze the possibility of sustainable ghost fishing for the lost pot to feed the fishes at anytime because there were blenny, silver whiting, bar-tailed flathead and shrimp including sea-eel in the lost pot. In the bioeconomic point, ghost fishing is competitive with the general fishing. Accordingly, usage of biodegradable plastic material for the plastic sea-eel pot will be better to reduce ghost fishing

Internal Wave Computations based on a Discontinuity in Dynamic Pressure (동압 계수의 불연속성을 이용한 내면파의 수치해석)

  • 신상묵;김동훈
    • Journal of the Society of Naval Architects of Korea
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    • v.41 no.4
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    • pp.17-29
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    • 2004
  • Internal waves are computed using a ghost fluid method on an unstructured grid. Discontinuities in density and dynamic pressure are captured in one cell without smearing or oscillations along a multimaterial interface. A time-accurate incompressible Navier-Stokes/Euler solver is developed based on a three-point backward difference formula for the physical time marching. Artificial compressibility is introduced with respect to pseudotime and an implicit method is used for the pseudotime iteration. To track evolution of an interface, a level set function is coupled with the governing equations. Roe's flux difference splitting method is used to calculate numerical fluxes of the coupled equations. To get higher order accuracy, dependent variables are reconstructed based on gradients which are calculated using Gauss theorem. For each edge crossing an interface, dynamic pressure is assigned for a ghost node to enforce the continuity of total pressure along the interface. Solitary internal waves are computed and the results are compared with other computational and experimental results.

Lightweight Key Point Detection Model Based on Multi-Scale Ghost Convolution for YOLOv8 (YOLOv8 을 위한 다중 스케일 Ghost 컨볼루션 기반 경량 키포인트 검출 모델)

  • Zihao Li;Inwhee Joe
    • Proceedings of the Korea Information Processing Society Conference
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    • 2024.05a
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    • pp.604-606
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    • 2024
  • 컴퓨터 비전 응용은 우리 생활에서 중요한 역할을 한다. 현재, 대규모 모델의 등장으로 딥 러닝의 훈련 및 운행 비용이 급격히 상승하고 있다. 자원이 제한된 환경에서는 일부 AI 프로그램을 실행할 수 없게 되므로, 경량화 연구가 필요하다. YOLOv8 은 현재 주요 목표 검출 모델 중 하나이며, 본 논문은 다중 스케일 Ghost 컨볼루션 모듈을 사용하여 구축된 새로운 YOLOv8-pose-msg 키포인트 검출 모델을 제안한다. 다양한 사양에서 새 모델의 매개변수 양은 최소 34% 감소할 수 있으며, 최대 59%까지 감소할 수 있다. 종합적인 검출 성능은 비교적 대규모 데이터셋에서 원래의 수준을 유지할 수 있으며, 소규모 데이터셋에서의 키포인트 검출은 30% 이상 증가할 수 있다. 동시에 최대 25%의 훈련 및 추론 시간을 절약할 수 있다.

Consideration about 'Heaven and Man' from review and analysis of 'Heaven's Will', 'Verification of Ghost' and 'Indeterminism' of Mozi (묵자의 「천지(天志)」, 「명귀(明鬼)」 및 「비명(非命)」 편 분석을 통한 천인(天人)관계 고찰)

  • Hwang, SeongKyu
    • The Journal of Korean Philosophical History
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    • no.53
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    • pp.165-190
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    • 2017
  • This thesis is for the analysis of the relationships between Mozi's 'Heaven and Man' through the inspection of meaning and emphasis in his three books, 'Heaven's Will', 'Verification of Ghost' and 'Indeterminism'. According to the previous study, the Heaven's Will and Verification of Ghost are justify Mozi's theory of theistic stance with the Heaven's authority. And in case of the 'Indeterminism', there seems to be positive and rational way of awareness and it's thought to be atheistic stance. It is thought that there is a rule of action which is about the personality principle, and it suggest that how the government rule the country, and how the people lead a life. And it is the ghost that give prize or punishment when they did something according to this principle or not. So, men should do their best in actual life to meet the heaven's will. Because my fate is not decided by heaven's order but my own action. And it is thought that the main point of 'the indeterminism' is about Heaven helps those who do independent and active efforts. In short, 'the Heaven's Will', Verification of Ghost' and 'Indeterminism' are neither contradiction nor conversion form theism to atheism. Mozi is thought to divide clearly about ghost's works and people's works, and it is expressed explicitly in his works 'Heaven's Will', 'Verification of Ghost' and 'Indeterminism'.

A Study on Touch-screen Development Using Visible-ray (가시광선을 이용한 터치스크린 구현에 대한 연구)

  • Park, Jun-Woo;Jeong, Yong-Jin
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.3
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    • pp.50-61
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    • 2011
  • The Infrared touch method is generally used for a mid and large-size touch screen. But this method has several problems, such as difficulty with installation of a touch-object recognition device, limited application and coordinate error in multi-point touch system. Since we can take advantages of both color and local information when we use general cameras for a touch screen, a touch screen using general camera is more efficient than infrared one. It also has an advantage of easy installation of a touch-object device. However, it did not much appeal in a market because of several problems, such as color sensitivity, illumination and reflected light. In this paper, we study a method for a touch screen using a general camera and image processing method to recognize touch objects and coordinate calculation method to single and multi-point touch screen. It has the same recognition performance as an infrared touch screen for single-point method. And it does not have ghost point problem by using distance information of touch object and camera in multi-point touch system. But recognition performances of multi-point touch screen are less than single-point. If we improve execution time, this method can replace an infrared method for a single point touch screen, according to result of experience.

GHOST ANALYSIS FOR THE OPTICS SYSTEM OF THE KASINICS (KASINICS 광학계의 고스트 분석)

  • Lee, Sung-Ho;Yuk, In-Soo;Jin, Ho;Pak, Soo-Jong;Han, Jeong-Yeol;Lee, Dae-Hee;Kong, Kyung-Nam;Cho, Seung-Hyun;Park, Young-Sik;Park, Jang-Hyun;Han, Won-Yong
    • Publications of The Korean Astronomical Society
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    • v.20 no.1 s.24
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    • pp.151-161
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    • 2005
  • The reimaging optics of the KASINICS (KASI Near Infrared Camera System) includes many transparent components like an entrance window, band-pass filters, and blocking filters. As observational targets or in-field background objects, bright stars may cause optical ghosts that can significantly degrade the system performance of the KASINICS. We estimated analytically the relative brightness of ghost components with respect to a point source and examined the effects of tilting optical components as a method of suppressing ghosts. We also performed numerical ray tracings including all the optical components and found the results are consistent with those of the analytic estimations. We conclude that the KASINICS will not suffer from significant ghost effects with appropriate anti-reflection coatings and fittings for the optical components.

CONSERVATIVE FINITE VOLUME METHOD ON BOUNDARY TREATMENTS FOR FLOW NETWORK SYSTEM ANALYSES (유동망 시스템 해석을 위한 경계처리에 대한 보존형 유한체적법)

  • Hong, S.W.;Kim, C.
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03a
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    • pp.19-26
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    • 2008
  • From numerical point of view on flow network system analyses, stagnation properties are not preserved along streamlines across geometric discontinuities. Hence, GJM and DTM using ghost cell and thermodynamic relations are developed to preserve the stagnation enthalpy for the boundaries, such as the interfaces between junction and branches and the interface between two pipes of different cross-sections in serial pipelines. Additionally, the resolving power and efficiencies of the 2nd order Godunov type FV schemes are investigated and estimated by the tracing of the total mechanical energy during calculating rapid transients. Among the approximate Riemann solvers, RoeM is more suitable with the proposed boundary treatments especially for junction than Roe's FDS because of its conservativeness of stagnation enthalpy across geometric discontinuities.

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CONSERVATIVE FINITE VOLUME METHOD ON BOUNDARY TREATMENTS FOR FLOW NETWORK SYSTEM ANALYSES (유동망 시스템 해석을 위한 경계처리에 대한 보존형 유한체적법)

  • Hong, S.W.;Kim, C.
    • 한국전산유체공학회:학술대회논문집
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    • 2008.10a
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    • pp.19-26
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    • 2008
  • From numerical point of view on flow network system analyses, stagnation properties are not preserved along streamlines across geometric discontinuities. Hence, GJM and DTM using ghost cell and thermodynamic relations are developed to preserve the stagnation enthalpy for the boundaries, such as the interfaces between junction and branches and the interface between two pipes of different cross-sections in serial pipelines. Additionally, the resolving power and efficiencies of the 2nd order Godunov type FV schemes are investigated and estimated by the tracing of the total mechanical energy during calculating rapid transients. Among the approximate Riemann solvers, RoeM is more suitable with the proposed boundary treatments especially for junction than Roe's FDS because of its conservativeness of stagnation enthalpy across geometric discontinuities.

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