• Title/Summary/Keyword: Illumination simulation

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Object VR-based 2.5D Virtual Textile Wearing System : Viewpoint Vector Estimation and Textile Texture Mapping (오브젝트 VR 기반 2.5D 가상 직물 착의 시스템 : 시점 벡터 추정 및 직물 텍스쳐 매핑)

  • Lee, Eun-Hwan;Kwak, No-Yoon
    • 한국HCI학회:학술대회논문집
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    • 2008.02a
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    • pp.19-26
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    • 2008
  • This paper is related to a new technology allowing a user to have a 360 degree viewpoint of the virtual wearing object, and to an object VR(Virtual Reality)-based 2D virtual textile wearing system using viewpoint vector estimation and textile texture mapping. The proposed system is characterized as capable of virtually wearing a new textile pattern selected by the user to the clothing shape section segmented from multiview 2D images of clothes model for object VR, and three-dimensionally viewing its virtual wearing appearance at a 360 degree viewpoint of the object. Regardless of color or intensity of model clothes, the proposed system is possible to virtually change the textile pattern with holding the illumination and shading properties of the selected clothing shape section, and also to quickly and easily simulate, compare, and select multiple textile pattern combinations for individual styles or entire outfits. The proposed system can provide higher practicality and easy-to-use interface, as it makes real-time processing possible in various digital environment, and creates comparatively natural and realistic virtual wearing styles, and also makes semi -automatic processing possible to reduce the manual works to a minimum. According to the proposed system, it can motivate the creative activity of the designers with simulation results on the effect of textile pattern design on the appearance of clothes without manufacturing physical clothes and, as it can help the purchasers for decision-making with them, promote B2B or B2C e-commerce.

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Transmission Probability of Car-to-Car Message Delivery Link based on Visible Light Communications (광무선통신기술을 이용한 차량간 메시지전달링크의 링크전송확률 분석)

  • Kang, Moon-Soo;Lee, Chung-Ghiu
    • Journal of Korea Multimedia Society
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    • v.14 no.6
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    • pp.752-758
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    • 2011
  • In this paper, we perform a research on a message delivery link based on visible light communication using illumination light-emitting diodes (LEDs) for car-to-car communications and the link transmission success probability is analyzed for the link. The message delivery system is modeled and the signal-to-noise ratio is calculated from the received optical power. Then, the link transmission probability is estimated from the calculated bit error rates (BERs). The message delivery system has optical links from an LED transmitter near the rear lamp of a car ahead to a receiver near the headlamp of a car behind, whose positions are assumed to follow the normal Gaussian distribution. The link transmission success probability is calculated considering the physical characteristics of the optical link. The car positions are generated according to the normal distribution and the bit error rates are calculated for all links. The link transmission success probability is defined. For the unoptimized optical car-to-car message delivery links, it is shown that the link transmission success probability is larger than 0.9 with the transmitted optical power of 400 mW and the semi-angle at half power of 30 degree.

Color Image Segmentation and Textile Texture Mapping of 2D Virtual Wearing System (2D 가상 착의 시스템의 컬러 영상 분할 및 직물 텍스쳐 매핑)

  • Lee, Eun-Hwan;Kwak, No-Yoon
    • Journal of KIISE:Computer Systems and Theory
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    • v.35 no.5
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    • pp.213-222
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    • 2008
  • This paper is related to color image segmentation and textile texture mapping for the 2D virtual wearing system. The proposed system is characterized as virtually wearing a new textile pattern selected by user to the clothing shape section, based on its intensity difference map, segmented from a 2D clothes model image using color image segmentation technique. Regardless of color or intensity of model clothes, the proposed system is possible to virtually change the textile pattern or color with holding the illumination and shading properties of the selected clothing shape section, and also to quickly and easily simulate, compare, and select multiple textile pattern combinations for individual styles or entire outfits. The proposed system can provide higher practicality and easy-to-use interface, as it makes real-time processing possible in various digital environment, and creates comparatively natural and realistic virtual wearing styles, and also makes semi-automatic processing possible to reduce the manual works to a minimum. According to the proposed system, it can motivate the creative activity of the designers with simulation results on the effect of textile pattern design on the appearance of clothes without manufacturing physical clothes and, as it can help the purchasers for decision-making with them, promote B2B or B2C e-commerce.

Analysis of Building Energy by the Typical Meteorological Data (표준기상데이터(부산지역) 적용에 따른 건축물에너지 분석)

  • Park, So-Hee;Yoo, Ho-Chun
    • 한국태양에너지학회:학술대회논문집
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    • 2008.11a
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    • pp.202-207
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    • 2008
  • Measures for coping with energy shortage are being sought all over the world. Following such a phenomenon, effort to use less energy in the design of buildings and equipment are being conducted. In particular, a program to evaluate the performance of a building comes into the spotlight. However. indispensable standard wether data to estimate the exact energy consumption of a building is currently unprepared. Thus, after appling standard weather data for four weather factors which were used in previous researches to Visual DOE 4.0, we compared it with the result of the existing data and evaluated them. For the monthly cooling and heating load of our target building, we used revised data for June, July, August, and September during which cooling load is applied. When not the existing data but the revised data was used, the research shows that an average of 14.9% increased in June, August, and September except for July. Also, in a case of heating load, the result by the revised data shows a reduction of an average of 11.9% from October to April during which heating load is applied. In particular, the heating loads of all months for which the revised data was used were more low than those of the existing data. In the maximum cooling and heating load according to load factors, the loads by residents and illumination for which the revised data was used were the same as those of the existing data, but the maximum cooling loads used by the two data have a difference in structures such as walls and roofs. Through the above results, the research cannot clearly grasp which weather data influences the cooling and heating load of a building. However, in the maximum loads by the change of weather data in four factors (dry-bulb temperature, web-bulb temperature, cloud amount, and wind speed) among 14 weather factors, the research shows that 5.95% in cooling load and 27.56% in heating load increased, and these results cannot be ignored. In order to make weather data for Performing energy performance evaluation for future buildings, the flow of weather data for the Present and past should be obviously grasped.

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Performance evaluation by simulation for the angular luminous intensity distributions of marine lanterns using a tilting aspherical Fresnel lens and a C-8 type light bulb (기울어진 비구면 프레넬 렌즈와 C-8 type 전구를 이용한 해상용 랜턴의 배광곡선 시뮬레이션을 통한 성능평가)

  • Cho Hyun Seok;Jo Jae Heung;Park Seungl Nam;Park Chul Woung;Kim Yong Wan;Kim Jong Tae
    • Korean Journal of Optics and Photonics
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    • v.15 no.6
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    • pp.511-518
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    • 2004
  • Providing marine signal lanterns with advantages of little weight as well as large aperture, a Fresnel lens has been adopted to transfer the beam from the lanterns up to 10 nautical miles (18.53 km). A Fresnel lens with the diameter of 250 mm and 300 mm was designed by a lens design program and optimized by adjusting the groove parameters of the lens. The angular luminous intensity distribution (ALID) of this lens was calculated by using an illumination analysis program considering the ALID of a light bulb. At the best alignment of the bulb, the maximum luminous intensities (MLI) of the lantern were 1000 cd (in the case of 250 mm diameter) and 1300 cd (in the case of 300 mm diameter). These are more than the critical value of 720 cd that is the Korean Standard of MLI for the marine lantern. The ALID was investigated as a function of misalignment from the lens focus to determine the tolerance of the alignment ranges.

Changes in plant hydraulic conductivity in response to water deficit

  • Kim, Yangmin X.;Sung, Jwakyung;Lee, Yejin;Lee, Seulbi;Lee, Deogbae
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.35-35
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    • 2017
  • How do plants take up water from soils especially when water is scarce in soils? Plants have a strategy to respond to water deficit to manage water necessary for their survival and growth. Plants regulate water transport inside them. Water flows inside the plant via (i) apoplastic pathway including xylem vessel and cell wall and (ii) cell-to-cell pathway including water channels sitting in cell membrane (aquaporins). Water transport across the root and leaf is explained by a composite transport model including those pathways. Modification of the components in those pathways to change their hydraulic conductivity can regulate water uptake and management. Apoplastic barrier is modified by producing Casparian band and suberin lamellae. These structures contain suberin known to be hydrophobic. Barley roots with more suberin content from the apoplast showed lower root hydraulic conductivity. Root hydraulic conductivity was measured by a root pressure probe. Plant root builds apoplastic barrier to prevent water loss into dry soil. Water transport in plant is also regulated in the cell-to-cell pathway via aquaporin, which has received a great attention after its discovery in early 1990s. Aquaporins in plants are known to open or close to regulate water transport in response to biotic and/or abiotic stresses including water deficit. Aquaporins in a corn leaf were opened by illumination in the beginning, however, closed in response to the following leaf water potential decrease. The evidence was provided by cell hydraulic conductivity measurement using a cell pressure probe. Changing the hydraulic conductivity of plant organ such as root and leaf has an impact not only on the speed of water transport across the plant but also on the water potential inside the plant, which means plant water uptake pattern from soil could be differentiated. This was demonstrated by a computer simulation with 3-D root structure having root hydraulic conductivity information and soil. The model study indicated that the root hydraulic conductivity plays an important role to determine the water uptake from soil with suboptimal water, although soil hydraulic conductivity also interplayed.

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Development of Autonomous Vehicle Learning Data Generation System (자율주행 차량의 학습 데이터 자동 생성 시스템 개발)

  • Yoon, Seungje;Jung, Jiwon;Hong, June;Lim, Kyungil;Kim, Jaehwan;Kim, Hyungjoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.19 no.5
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    • pp.162-177
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    • 2020
  • The perception of traffic environment based on various sensors in autonomous driving system has a direct relationship with driving safety. Recently, as the perception model based on deep neural network is used due to the development of machine learning/in-depth neural network technology, a the perception model training and high quality of a training dataset are required. However, there are several realistic difficulties to collect data on all situations that may occur in self-driving. The performance of the perception model may be deteriorated due to the difference between the overseas and domestic traffic environments, and data on bad weather where the sensors can not operate normally can not guarantee the qualitative part. Therefore, it is necessary to build a virtual road environment in the simulator rather than the actual road to collect the traning data. In this paper, a training dataset collection process is suggested by diversifying the weather, illumination, sensor position, type and counts of vehicles in the simulator environment that simulates the domestic road situation according to the domestic situation. In order to achieve better performance, the authors changed the domain of image to be closer to due diligence and diversified. And the performance evaluation was conducted on the test data collected in the actual road environment, and the performance was similar to that of the model learned only by the actual environmental data.

MCBP Neural Netwoek for Effcient Recognition of Tire Claddification Code (타이어 분류 코드의 효율적 인식을 위한 MCBP망)

  • Koo, Gun-Seo;O, Hae-Seok
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.2
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    • pp.465-482
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    • 1997
  • In this paper, we have studied on cinstructing code-recognition shstem by neural network according to a image process taking the DOT classification code stamped on tire surface.It happened to a few problems that characters distorted in edge by diffused reflection and two adjacent characters take the same label,even very sen- sitive to illumination ofr recognition the stamped them on tire.Thus,this paper would propose the algorithm for tire code under being cinscious of these properties and prove the algorithm drrciency with a simulation.Also,we have suggerted the MCBP network composing of multi-linked recognizers of dffcient identify the DOT code being tire classification code.The MCBP network extracts the projection balue for classifying each character's rdgion after taking out the prjection of each chracter's region on X,Y axis,processes each chracters by taking 7$\times$8 normalization.We have improved error rate 3% through the MCBP network and post-process comparing the DOT code Database. This approach has a accomplished that learming time get's improvenent at 60% and recognition rate has become to 95% from 90% than BckPropagation with including post- processing it has attained greate rates of entire of tire recoggnition at 98%.

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VLC Based Positioning Scheme in Vehicle-to-Infra(V2I) Environment (차량-인프라간 가시광 통신 기반 측위 기술)

  • Kim, Byung Wook;Song, Deok-Weon;Lee, Ji-Hwan;Jung, Sung-Yoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.3
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    • pp.588-594
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    • 2015
  • Although GPS technology for location positioning system has been widely used, it is difficult to be used in intelligent transport systems, due to the large positioning error and limited area for receiving radio signals. Thanks to the rapid development of LED technology, LED lights become popular in many applications. Especially, visible light communications (VLC) has raised a lot of interests because of the simultaneous functioning of LED illumination and communication. Recent studies on positioning system using VLC mainly focused on indoor environments and still difficult to satisfy positioning accuracy and simple implementation simultaneously. In this paper, we propose a positioning system based on VLC using the coordinate information of LEDs installed on the road infrastructure. Extracting the LED signal, obtained through VLC, from the easily accessible camera image, it is possible to estimate the position of the car on the road. Simulation results show that the proposed scheme can achieve a high positioning accuracy of 1 m when large number of pixels is utilized and the distance from the LED light is close.

Localizing Head and Shoulder Line Using Statistical Learning (통계학적 학습을 이용한 머리와 어깨선의 위치 찾기)

  • Kwon, Mu-Sik
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.2C
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    • pp.141-149
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    • 2007
  • Associating the shoulder line with head location of the human body is useful in verifying, localizing and tracking persons in an image. Since the head line and the shoulder line, what we call ${\Omega}$-shape, move together in a consistent way within a limited range of deformation, we can build a statistical shape model using Active Shape Model (ASM). However, when the conventional ASM is applied to ${\Omega}$-shape fitting, it is very sensitive to background edges and clutter because it relies only on the local edge or gradient. Even though appearance is a good alternative feature for matching the target object to image, it is difficult to learn the appearance of the ${\Omega}$-shape because of the significant difference between people's skin, hair and clothes, and because appearance does not remain the same throughout the entire video. Therefore, instead of teaming appearance or updating appearance as it changes, we model the discriminative appearance where each pixel is classified into head, torso and background classes, and update the classifier to obtain the appropriate discriminative appearance in the current frame. Accordingly, we make use of two features in fitting ${\Omega}$-shape, edge gradient which is used for localization, and discriminative appearance which contributes to stability of the tracker. The simulation results show that the proposed method is very robust to pose change, occlusion, and illumination change in tracking the head and shoulder line of people. Another advantage is that the proposed method operates in real time.