• Title/Summary/Keyword: Direct3D

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A Study of the 3D-Reconstruction of indoor using Stereo Camera System (스테레오 카메라를 이용한 실내환경의 3차원 복원에 관한 연구)

  • Lee Dong-Hun;Um Dae-Youn;Kang Hoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.1
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    • pp.42-47
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    • 2005
  • In this papcr, we address the 3D reconstruction of the indoor circumstance using what the data is extracted by a pall of image from Stereo Camera. Generally sucaking, there arc three methods to extract 3-Dimensional data using IR sensor, Laser sensor and Stereo camera sensor. The best is stereo camera sensor which can show a high performance at a reasonable price. We used 'Window Correlation Matching Method' to extract 3-Dimensional data in stereo image. We proposed new Method to reduce error data, said 'Histogram Weighted Hough Transform'. Owing to this mettled, we reduced error data in each stereo image. So reconstruction is well done. 3-Dimensional Reconstruction is accomplished by using the DirectX that is well known as 3D-Game development tool. We show that the stereo camera can be not only used to extract 3-dimensional data but also applied to reconstruct the 3-Dimensional circumstance. And we try to reduce the error data using various method.

Fluorinated Esters Derived from Terpenes

  • Joseph D. Park;Robert L. Settine
    • Journal of the Korean Chemical Society
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    • v.8 no.3
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    • pp.128-130
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    • 1964
  • Fluorinated acid chlorides in the C$_3$ to C$_9$ range were reacted with diols prepared from terpene diacids to give good yields of potentially useful esters. These esters were shown to be of greater stability and low temperature properties than those prepared from fluorinated alcohols and corresponding terpene diacids by direct esterification.

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Dynamic Reconstruction Algorithm of 3D Volumetric Models (3D 볼류메트릭 모델의 동적 복원 알고리즘)

  • Park, Byung-Seo;Kim, Dong-Wook;Seo, Young-Ho
    • Journal of Broadcast Engineering
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    • v.27 no.2
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    • pp.207-215
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    • 2022
  • The latest volumetric technology's high geometrical accuracy and realism ensure a high degree of correspondence between the real object and the captured 3D model. Nevertheless, since the 3D model obtained in this way constitutes a sequence as a completely independent 3D model between frames, the consistency of the model surface structure (geometry) is not guaranteed for every frame, and the density of vertices is very high. It can be seen that the interconnection node (Edge) becomes very complicated. 3D models created using this technology are inherently different from models created in movie or video game production pipelines and are not suitable for direct use in applications such as real-time rendering, animation and simulation, and compression. In contrast, our method achieves consistency in the quality of the volumetric 3D model sequence by linking re-meshing, which ensures high consistency of the 3D model surface structure between frames and the gradual deformation and texture transfer through correspondence and matching of non-rigid surfaces. And It maintains the consistency of volumetric 3D model sequence quality and provides post-processing automation.

Design of a 3D Graphics Geometry Accelerator using the Programmable Vertex Shader (Programmable Vertex Shader를 내장한 3차원 그래픽 지오메트리 가속기 설계)

  • Ha Jin-Seok;Jeong Hyung-Gi;Kim Sang-Yeon;Lee Kwang-Yeob
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.43 no.9 s.351
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    • pp.53-58
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    • 2006
  • A Vertex Shader is designed to show more 3D graphics expressions, and to increase flexibility of the fixed function T&L (Transform and Lighting) engine. Design of this Shader is based on Vertex Shader 1.1 of DirectX 8.1 and OpenGL ARB. The Vertex Shader consists of four floating point ALUs for vectors operation. The previous 32bits floating point data type is replaced to 24bits floating point data type in order to design the Vertex Shader that consume low-power and occupy small area. A Xilinx Virtex2 300M gate module is used to verify behaviour of the core. The result of Synopsys synthesis shows that the proposed Vertex Shader performs 115MHz speed at the TSMC 0.13um process and it can operate as the rate of 12.5M Polygons/sec. It shows the complexity of 110,000 gates in the same process.

Study on Aerodynamic Optimization Design Process of Multistage Axial Turbine

  • Zhao, Honglei;Tan, Chunqing;Wang, Songtao;Han, Wanjin;Feng, Guotai
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.03a
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    • pp.130-135
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    • 2008
  • An aerodynamic optimization design process of multistage axial turbine is presented in this article: first, applying quasi-three dimensional(Q3D) design methods to conduct preliminary design and then adopting modern optimization design methods to implement multistage local optimization. Quasi-three dimensional(Q3D) design methods, which mainly refer to S2 flow surface direct problem calculation, adopt the S2 flow surface direct problem calculation program of Harbin Institute of Technology. Multistage local optimization adopts the software of Numeca/Design3D, which jointly adopts genetic algorithm and artificial neural network. The major principle of the methodology is that the successive design evaluation is performed by using an artificial neural network instead of a flow solver and the genetic algorithms may be used in an efficient way. Flow computation applies three-dimensional viscosity Navier Stokes(N-S) equation solver. Such optimization process has three features: (i) local optimization based on aerodynamic performance of every cascade; (ii) several times of optimizations being performed to every cascade; and (iii) alternate use of coarse grid and fine grid. Such process was applied to optimize a three-stage axial turbine. During the optimization, blade shape and meridional channel were respectively optimized. Through optimization, the total efficiency increased 1.3% and total power increased 2.4% while total flow rate only slightly changed. Therefore, the total performance was improved and the design objective was achieved. The preliminary design makes use of quasi-three dimensional(Q3D) design methods to achieve most reasonable parameter distribution so as to preliminarily enhance total performance. Then total performance will be further improved by adopting multistage local optimization design. Thus the design objective will be successfully achieved without huge expenditure of manpower and calculation time. Therefore, such optimization design process may be efficiently applied to the aerodynamic design optimization of multistage axial turbine.

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Design of RBFNNs Pattern Classifier Realized with the Aid of PSO and Multiple Point Signature for 3D Face Recognition (3차원 얼굴 인식을 위한 PSO와 다중 포인트 특징 추출을 이용한 RBFNNs 패턴분류기 설계)

  • Oh, Sung-Kwun;Oh, Seung-Hun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.6
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    • pp.797-803
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    • 2014
  • In this paper, 3D face recognition system is designed by using polynomial based on RBFNNs. In case of 2D face recognition, the recognition performance reduced by the external environmental factors such as illumination and facial pose. In order to compensate for these shortcomings of 2D face recognition, 3D face recognition. In the preprocessing part, according to the change of each position angle the obtained 3D face image shapes are changed into front image shapes through pose compensation. the depth data of face image shape by using Multiple Point Signature is extracted. Overall face depth information is obtained by using two or more reference points. The direct use of the extracted data an high-dimensional data leads to the deterioration of learning speed as well as recognition performance. We exploit principle component analysis(PCA) algorithm to conduct the dimension reduction of high-dimensional data. Parameter optimization is carried out with the aid of PSO for effective training and recognition. The proposed pattern classifier is experimented with and evaluated by using dataset obtained in IC & CI Lab.

Synthesis and Anaiysis of Photohnninescence Properties of $^5D_1$$^7F_1$ Transition in $LaGaO_3$:$Eu^{3+}$ Red Phosphor ($LaGaO_3$:$Eu^{3+}$형광체의 합성 및 발광 특성)

  • Kim, Kyoung Hwa;Choi, Yoon Young;Sohn, Kee Sun;Kim, Chang Hae;Park, Hee Dong;Choe, Se Young
    • Journal of the Korean Chemical Society
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    • v.44 no.5
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    • pp.453-459
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    • 2000
  • FED has deserved an intensive attentioD as a new flat panel display. The present investigationaims at undemtanding the photoluminescence and cathodoluminescent properties of hGaO$_3$: $Eu^{3+}$ phosphor bytaking into account the possibility that this phosphor could be applied for FED. In onler to investigate on.sucha detailed behavior; 8everM experimental skil18 Je conducted to the LaGaO$_3$:$Eu^{3+}$ phosphoL The excimtion srectrum artd emission spectmn were rnezsured in the UV range and then decay curve of $^5D_0$+$^7F_j$transitions\vas examined. The decay behavior of $^5D_0$ emission was anMyzed by a newly Iuoposed cross-relaxation mech-ani8In in asswiation with inteFwnter di1ffision (or migration). The cross-mlaxation from $^5D_0$ to CTB (Cha'geTransfer Band) wuld be a quite retsonable by considering the excitation spectrum. It could be also found thatthe quenching type was changed from ditfrsion controlled process to the direct quenching process -s inJeasing $Eu^{3+}$ oncntration.

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Performance of a Modified Multicarrier Direct Sequence CDMA System

  • Lee, Dong-Wook;Lee, Hun;Kim, Jin-Su
    • ETRI Journal
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    • v.19 no.1
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    • pp.1-12
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    • 1997
  • In this paper, we present an improved multicarrier direct sequence (DS) code division multiple access (CDMA) scheme by modifying the system originally proposed by Kondo and Milstein [13]. In this modified system, different spreading sequences multiplied by a data sequence modulate different carriers. This is to prevent the multiple access capability from reducing when the fading characteristics of different carrier frequencies are highly correlated. We have derived a formula which determines the mean values of the relative received signal strength in a single carrier DS CDMA rake system and in a multicarrier DS-CDMA system. We present results on the comparison of the bit error rate (BER) performance of the two systems including the effect of correlation between fading characteristics of different frequencies under various multipath fading conditions. The results indicate that with 50 users the modified multicarrier DS CDMA system can achieve an uncoded irreducible BER of $1.7{\times}10^{-3}$ with an average received signal-to-noise ratio per bit of 10dB, which is better that $3.0{\times}10^{-3}$ achieved by the single carrier DS CDMA rake system, and also show that if multicarrier CDMA system is used with respect to single carrier CDMA system, the SNR gain is up to 4.5 dB for the uncode BER of $10^{-3}$ being achieved.

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