• Title/Summary/Keyword: Surface mapping

Search Result 497, Processing Time 0.023 seconds

Design of an Effective Bump Mapping Hardware Architecture Using Angular Operation (각 연산을 이용한 효과적인 범프 매핑 하드웨어 구조 설계)

  • 이승기;박우찬;김상덕;한탁돈
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.30 no.11
    • /
    • pp.663-674
    • /
    • 2003
  • Bump mapping is a technique that represents the detailed parts of the object surface, such as a perturberance of the skin of a peanut, using the geometry mapping without complex modeling. However, the hardware implementation for bump mapping is considerable, because a large amount of per pixel computation, including the normal vector shading, is required. In this paper, we propose a new bump mapping algorithm using the polar coordinate system and its hardware architecture. Compared with other existing architectures, our approach performs bump mapping effectively by using a new vector rotation method for transformation into the reference space and minimizing illumination calculation. Consequently, our proposed architecture reduces a large amount of computation and hardware requirements.

Robust Dynamic Projection Mapping onto Deforming Flexible Moving Surface-like Objects (유연한 동적 변형물체에 대한 견고한 다이내믹 프로젝션맵핑)

  • Kim, Hyo-Jung;Park, Jinho
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
    • /
    • v.7 no.6
    • /
    • pp.897-906
    • /
    • 2017
  • Projection Mapping, also known as Spatial Augmented Reality(SAR) has attracted much attention recently and used for many division, which can augment physical objects with projected various virtual replications. However, conventional approaches towards projection mapping have faced some limitations. Target objects' geometric transformation property does not considered, and movements of flexible objects-like paper are hard to handle, such as folding and bending as natural interaction. Also, precise registration and tracking has been a cumbersome process in the past. While there have been many researches on Projection Mapping on static objects, dynamic projection mapping that can keep tracking of a moving flexible target and aligning the projection at interactive level is still a challenge. Therefore, this paper propose a new method using Unity3D and ARToolkit for high-speed robust tracking and dynamic projection mapping onto non-rigid deforming objects rapidly and interactively. The method consists of four stages, forming cubic bezier surface, process of rendering transformation values, multiple marker recognition and tracking, and webcam real time-lapse imaging. Users can fold, curve, bend and twist to make interaction. This method can achieve three high-quality results. First, the system can detect the strong deformation of objects. Second, it reduces the occlusion error which reduces the misalignment between the target object and the projected video. Lastly, the accuracy and the robustness of this method can make result values to be projected exactly onto the target object in real-time with high-speed and precise transformation tracking.

Analysis of Road Surface Temperature Change Patterns using Machine Learning Algorithms (기계학습을 이용한 노면온도변화 패턴 분석)

  • Yang, Choong Heon;Kim, Seoung Bum;Yoon, Chun Joo;Kim, Jin Guk;Park, Jae Hong;Yun, Duk Geun
    • International Journal of Highway Engineering
    • /
    • v.19 no.2
    • /
    • pp.35-44
    • /
    • 2017
  • PURPOSES: This study suggests a specific methodology for the prediction of road surface temperature using vehicular ambient temperature sensors. In addition, four kind of models is developed based on machine learning algorithms. METHODS : Thermal Mapping System is employed to collect road surface and vehicular ambient temperature data on the defined survey route in 2015 and 2016 year, respectively. For modelling, all types of collected temperature data should be classified into response and predictor before applying a machine learning tool such as MATLAB. In this study, collected road surface temperature are considered as response while vehicular ambient temperatures defied as predictor. Through data learning using machine learning tool, models were developed and finally compared predicted and actual temperature based on average absolute error. RESULTS : According to comparison results, model enables to estimate actual road surface temperature variation pattern along the roads very well. Model III is slightly better than the rest of models in terms of estimation performance. CONCLUSIONS : When correlation between response and predictor is high, when plenty of historical data exists, and when a lot of predictors are available, estimation performance of would be much better.

Topographic Monitoring over Land Surface using Radar Altimeter

  • Kim, Yong-Hoon
    • Proceedings of the KSRS Conference
    • /
    • 1998.09a
    • /
    • pp.174-179
    • /
    • 1998
  • In this paper, the radar altimeter for topographic mapping over land is introduced and the characteristics of the return signals are analyzed. The radar system is described briefly and the requirements to get the fine resolution of the terrain surface height are considered. The designed radar altimeter was tested on the landscape in the near of Stuttgart. The measured data shows very fine profile of the test landscape and the height errors induced from different geometrical structure of the land surface are acquired in the measurement. In the test area, most characteristics of radar return signals over land could be tested and the results of the topographic mapping using our radar altimeter can be used for future radar altimeter development for land applications.

  • PDF

Surface Mapping of Masseter for Botulinum Toxin Injection (교근에서 보툴리눔 독소 주사점의 표지화)

  • Kim, Jun Hyung;Lee, Min Jae;Kim, Hyun Ji;Son, Dae Gu;Han, Ki Hwan;Lee, So Young;Lim, Jung Guen;Choi, In Jang
    • Archives of Plastic Surgery
    • /
    • v.32 no.3
    • /
    • pp.311-313
    • /
    • 2005
  • Generally, many Asian women tend to dislike the square jaw, as they believe it makes the face look wider, giving a stubborn and strong impression. Contouring of the mandible is therefore a relatively common aesthetic procedure among Asians. These days, the use of botulinum toxin for contouring of the lower face offer simple alternative to surgery. Motor point, which is the site over a muscle where its contraction may be elicited by a minimal intensity short duration electrical stimulus, is the optimal injection point of botulinum toxin. Study was undertaken to identify the location of motor point of the masseter muscle and the skin surface landmark. First, the thickest point of the masseter muscle was inspected through palpation and inspection by 3 different individual plastic surgeons and then compound muscle action potentials(CMAPs) of masseter muscle in 15 health volunteers were recorded using EMG. For the localization of the measured points, line between lateral canthus to the mandibular angle was used. Location of motor points were mapped to skin surface from lateral canthus in a percentage of the distance along the landmark line and in distance in millimeters. The clinical injection point was located at 71.69 percentile and 7.3 mm of the landmark line. The motor point test was located at 72.54 percentile and 7.1 mm of the landmark line. The depth of motor point was 16mm. There was no statistically significant difference between the clinical injection point and the motor point. We conclude that surface mapping of motor point of the masseter muscle would increase accessibility and accuracy in botulinum toxin injection for contouring of the lower face.

Impervious Surface Mapping of Cheongju by Using RapidEye Satellite Imagery (RapidEye 위성영상을 이용한 청주시의 불투수면지도 생성기법)

  • Park, Hong Lyun;Choi, Jae Wan;Choi, Seok Keun
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.22 no.1
    • /
    • pp.71-79
    • /
    • 2014
  • Most researches have created the impervious surface map by using low-spatial-resolution satellite imagery and are inefficient to generate the object-based impervious map with a broad area. In this study, segment-based impervious surface mapping algorithm is proposed using the RapidEye satellite imagery in order to map impervious area. At first, additional bands are generated by using TOA reflectance conversion RapidEye data. And then, shadow and water class are extracted using training data of converted reflectance image. Object-based impervious surface can be generated by spectral mixture analysis based on land cover map of Ministry of Environment with medium scale, in the case of other classes except shadow and water classes. The experiment shows that result by our method represents high classification accuracy compared to reference data, quantitatively.

Three Dimensional Finite Element Inverse Analysis of Rectangular Cup and S-Rail Forming Processes using a Direct Mesh Mapping Method (직접 격자 사상법을 이용한 직사각컵 및 S-Rail 성형공정의 3차원 유한요소 역해석)

  • Kim S. H.;Huh H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 2001.10a
    • /
    • pp.81-84
    • /
    • 2001
  • An inverse finite element approach is employed for more capability to design the optimum blank shape from the desired final shape with small amount of computation time and effort. In some drawing or stamping simulation with inverse method, it is difficult to apply inverse scheme due to the large aspect ratio or steep vertical angle of inclination. The reason is that initial guesses are hard to make out with present method for those cases. In this paper, a direct mesh marring scheme to generate initial guess on the sliding constraint surface described by finite element patches is suggested for one step inverse analysis to calculate initial blank shape. Radial type mapping is adopted for the simulation of rectangular cup drawing process with large aspect ratio and parallel type mapping for the simulation of S-Rail forming process with steep vertical angle of inclination.

  • PDF

Per-Pixel Displacement Mapping Using Angular Operations (각 연산을 이용한 픽셀 당 변위 매핑)

  • Lee, Seung-Gi;Lee, Won-Jong;Han, Tack-Don
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2006.11a
    • /
    • pp.295-298
    • /
    • 2006
  • 본 논문에서는 극 좌표계에서의 벡터 표현 방식을 이용한 per-pixel displacement mapping 방법을 제시한다. per-pixel displacement mapping은 triangle mesh의 처리 방식에 상관없이 변위매핑을 수행할 수 있도록 한 것으로, 2차원 screen space로 projection 된 triangle의 각 pixel의 위치를 객체 표면 정보에 따라 displacement 해주는 방법이다. 이는 기 검증된 범프매칭 하드웨어에 약간의 하드웨어를 추가함으로써 변위매핑을 수행할 수 있도록 한 효과적인 구조이다. 제안 방식에 의해 생성된 영상과 기존 방식에 의해 생성된 영상을 비교해본 결과, 시각적으로 거의 차이가 없음을 알 수 있다.

  • PDF

Regional Scale Evapotranspiration Mapping using Landsat 7 ETM+ Land Surface Temperature and NDVI Space (Landsat ETM+영상의 지표면온도와 NDVI 공간을 이용한 광역 증발산량의 도면화)

  • Na, Sang-Il;Park, Jong-Hwa
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.50 no.3
    • /
    • pp.115-123
    • /
    • 2008
  • Evapotranspiration mapping using both meteorological ground-based measurements and satellite-derived information has been widely studied during the last few decades and various methods have been developed for this purpose. It is significant and necessary to estimate regional evapotranspiration (ET) distribution in the hydrology and water resource research. The study focused on analyzing the surface ET of Chungbuk region using Landsat 7 ETM imagery. For this process, we estimated the regional daily evapotranspiration on May 8, 2000. The estimation of surface evapotranspiration is based on the relationship between Temperature Vegetation Dryness Index (TVDI) and Morton's actual ET. TVDI is the relational expression between Normalized Difference of Vegetation Index (NDVI) and Land Surface Temperature (LST). The distribution of NDVI corresponds well with that of land-use/land cover in Chungbuk. The LST of several part of city in Chungbuk region is higher in comparison with the averaged LST. And TVDI corresponds too well with that of land cover/land use in Chungbuk region. The low evapotranspiration availability is distinguished over the large city like Cheongju-si, Chungju-si and the difference of evapotranspiration availability on forest and paddy is high.

Application of Library-Based Texture Mapping Method (라이브러리 기반의 Texture Mapping 기법 활용연구)

  • Song Jeong-Heon;Park Su-Yong;Lim Hyo-Suk;Kim Yong-Il
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2006.04a
    • /
    • pp.369-373
    • /
    • 2006
  • A 3D modeling of urban area can be composed the terrain modeling that can express specific and shape of the terrain and the object modeling such as buildings, trees and facilities which are found in urban areas. Especially in a 3D modeling of building, it is very important to make a unit model by simplifying 3D structure and to take a texture mapping, which can help visualize surface information. In this study, the texture mapping technique, based on library for 3D urban modeling, was used for building modeling. This technique applies the texture map in the form of library which is constructed as building types, and then take mapping to the 3D building frame. For effectively apply, this technique, we classified buildings automatically using LiDAR data and made 3D frame using LiDAR and digital map. To express the realistic building texture, we made the texture library using real building photograph.

  • PDF