• Title/Summary/Keyword: complex representation

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Scattered Light Representation in Accordance with the Material Using Scatterer Template in Volume Rendering (볼륨 렌더링에서 산란자 템플릿을 이용한 재질별 산란광 표현)

  • Lee, Byeong-Joon;Kwon, Koojoo;Shin, Byeong-Seok
    • KIPS Transactions on Software and Data Engineering
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    • v.5 no.12
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    • pp.677-684
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    • 2016
  • For realistic rendering volume to calculate the light effects as well as the shade is essential. In order to produce the high quality of the resulting image, it is necessary to represent a global illumination, and it should be considered an indirect effect of the direct impact and scattering of light. It requires a lot of resources in order to perform this operation and, in particular, is very expensive when large amounts of data to be rendered as a volume data is consumed. In this paper, we generate a scatterer template according to the physical laws for each material. Considering that each object having material property stores photons of the template based on the Lambert illumination model. When the volume rendering in this paper, using the photon is stored in the template, based on the voxel to be sampled within the examination volume occluded, and it represents the global illumination of the scattering. Because the materials produced by the template requires a less resource only if comprised of a complex material, a simple operation can be expressed within the scattering volume at a low cost through.

Simulation of non-Gaussian stochastic processes by amplitude modulation and phase reconstruction

  • Jiang, Yu;Tao, Junyong;Wang, Dezhi
    • Wind and Structures
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    • v.18 no.6
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    • pp.693-715
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    • 2014
  • Stochastic processes are used to represent phenomena in many diverse fields. Numerical simulation method is widely applied for the solution to stochastic problems of complex structures when alternative analytical methods are not applicable. In some practical applications the stochastic processes show non-Gaussian properties. When the stochastic processes deviate significantly from Gaussian, techniques for their accurate simulation must be available. The various existing simulation methods of non-Gaussian stochastic processes generally can only simulate super-Gaussian stochastic processes with the high-peak characteristics. And these methodologies are usually complicated and time consuming, not sufficiently intuitive. By revealing the inherent coupling effect of the phase and amplitude part of discrete Fourier representation of random time series on the non-Gaussian features (such as skewness and kurtosis) through theoretical analysis and simulation experiments, this paper presents a novel approach for the simulation of non-Gaussian stochastic processes with the prescribed amplitude probability density function (PDF) and power spectral density (PSD) by amplitude modulation and phase reconstruction. As compared to previous spectral representation method using phase modulation to obtain a non-Gaussian amplitude distribution, this non-Gaussian phase reconstruction strategy is more straightforward and efficient, capable of simulating both super-Gaussian and sub-Gaussian stochastic processes. Another attractive feature of the method is that the whole process can be implemented efficiently using the Fast Fourier Transform. Cases studies demonstrate the efficiency and accuracy of the proposed algorithm.

Extraction of Design Rule from Han-Style Bathroom Design Using Rough Set Theory (러프집합이론을 이용한 한스타일 욕실공간의 구성규칙 추출에 관한 연구)

  • Park, Jin-A;Kim, Soo-Am
    • Journal of the Korean housing association
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    • v.24 no.6
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    • pp.199-208
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    • 2013
  • Developing a modern Han-style design and providing support for the commercialization development model in recent years has been propelled by the Han-style Support Strategies of the central government in conjunction with Han-style revitalization related projects that reflect the efforts of local governments. Han-style revitalization, the rekindling and revaluing of human behavior and interest in local governments following the social and cultural changes of the past decades, has emerged as an increasingly traditional area of concern in Han-style design. The purpose of the study was to provide a method which clarifies the design rules of the Han-style bathroom based on an evaluation of sensibilities and a rough set theory, and to give the components meaning and to systematize the method. Essentially, the Han-style bathroom design evaluation is a complex multi-criteria decision making process that seeks to improve the effectiveness and objectively of the Han-style bathroom design. Han-style bathroom design can be displayed in a graphical representation in response to input from the evaluation concerning sensibilities. Because the graphical representation is composed of 3D data, it is possible to display the Han-style bathroom design form in any desired perspective and also to perform shading and other operations. With the proposed method, it is possible to obtain a combination of several contributory components which can be referred to as Reducts, Covering Index and Column Score. Han-Style/Non Han-Style Bathroom Designs were identified by the combination of several components.

Force limited vibration testing: an evaluation of the computation of C2 for real load and probabilistic source

  • Wijker, J.J.;de Boer, A.;Ellenbroek, M.H.M.
    • Advances in aircraft and spacecraft science
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    • v.2 no.2
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    • pp.217-232
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    • 2015
  • To prevent over-testing of the test-item during random vibration testing Scharton proposed and discussed the force limited random vibration testing (FLVT) in a number of publications. Besides the random vibration specification, the total mass and the turn-over frequency of the load (test item), $C^2$ is a very important parameter for FLVT. A number of computational methods to estimate $C^2$ are described in the literature, i.e., the simple and the complex two degrees of freedom system, STDFS and CTDFS, respectively. The motivation of this work is to evaluate the method for the computation of a realistic value of $C^2$ to perform a representative random vibration test based on force limitation, when the adjacent structure (source) description is more or less unknown. Marchand discussed the formal description of getting $C^2$, using the maximum PSD of the acceleration and maximum PSD of the force, both at the interface between load and source. Stevens presented the coupled systems modal approach (CSMA), where simplified asparagus patch models (parallel-oscillator representation) of load and source are connected, consisting of modal effective masses and the spring stiffness's associated with the natural frequencies. When the random acceleration vibration specification is given the CSMA method is suitable to compute the value of the parameter $C^2$. When no mathematical model of the source can be made available, estimations of the value $C^2$ can be find in literature. In this paper a probabilistic mathematical representation of the unknown source is proposed, such that the asparagus patch model of the source can be approximated. The chosen probabilistic design parameters have a uniform distribution. The computation of the value $C^2$ can be done in conjunction with the CSMA method, knowing the apparent mass of the load and the random acceleration specification at the interface between load and source, respectively. Data of two cases available from literature have been analyzed and discussed to get more knowledge about the applicability of the probabilistic method.

Numerical Calculation Method for Paraxial Zoom Loci of Complicated Zoom Lenses with Infinite Object Distance by Using Gaussian Bracket Method (가우스 괄호법을 이용한 무한 물점을 갖는 복잡한 줌 렌즈의 수치해석적인 근축광선 줌 궤적 추적법)

  • Yoo, Nam-Jun;Kim, Won-Seob;Jo, Jae-Heung;Ryu, Jae-Myung;Lee, Hae-Jin;Kang, Geon-Mo
    • Korean Journal of Optics and Photonics
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    • v.18 no.6
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    • pp.410-420
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    • 2007
  • We theoretically derive the set of utilizable paraxial zoom locus equations for all complicated zoom lens systems with infinite object distance, such as a camera zoom lens, by using the Gaussian bracket method and the matrix representation of paraxial ray tracing. And we make the zoom locus program according to these equations in Visual Basic. Since we have applied the paraxial ray tracing equations into Gaussian bracket representation, the resultant program systematically simplifies various constraints of the zoom loci of various N group types. Consequently, the solutions of this method can be consistently used in all types of zoom lens in the step of initial design about zoom loci. Finally, in order to verify the usefulness of this method, we show that one example among 4 groups and that among 5 groups, which are very complex zoom lens systems, can be rapidly and with versatility traced through various interpolations by using this program.

A Study on Wave Responses of Vertical Tension-Leg Circular Floating Bodies (연직인장계류된 원형부유체의 파랑응답에 관한 연구)

  • Lee, Kwang-Ho;Kim, Chang-Hoon;Kim, Do-Sam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.23 no.3
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    • pp.248-257
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    • 2011
  • In the present study, we proposed a new numerical wave tank model to analyze the vertical tension-leg circular floating bodies, using a 2-D Navier-Stokes solver. An IBM(Immersed Boundary Method) capable of handling interactions between waves and moving structures with complex geometry on a standard regular Cartesian grid system is coupled to the VOF(Volume of Fluid) method for tracking the free surface. Present numerical results for the motions of the floating body were compared with existing experimental data as well as numerical results based on FAVOR(Fractional Area Volume Obstacle Representation) algorithm. For detailed examinations of the present model, the additional hydraulic experiments for floating motions and free surface transformations were conducted. Further, the versatility of the proposed numerical model was verified via the numerical and physical experiments for the general rectangular floating bodies. Numerical results were compared with experiments and good agreement was archived.

A Study on the Interior Design representation-language from image scale of Trend - Focused on 2008~09 international Fair - (이미지 스케일에 따른 트랜드 중심의 실내디자인 표현어휘 연구 - 2008~09년도 국제박람회를 중심으로 -)

  • Sheen, Dong-Kwan;Han, Young-Ho
    • Korean Institute of Interior Design Journal
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    • v.19 no.1
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    • pp.112-120
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    • 2010
  • Generally, Interior design understood as shapes, lines, spaces, tones, quality, and principal. And people research these with a study of formative approach. The six elements of above categories are basis of expansion for the various designs. In this study, the represented design language is extracted by the basic 6 stages and re-divided into classes. This study presented by the Kobayashi-scale image of the current trends in the assignment to examine the cultural, functional, sensory vocabulary, three elements were classified by the assignment about 2008~2009 international fair by trend and design direction for the image. If we look into the categorized format of the design, it reflects mixed culture with emotional approach and shows direction of design constantly. Especially, compared to the year 2008, the design of year 2009 has tendency as an emotional translator regarding the verbal expression. In other words, it becomes more concrete to express the design of emotions for human beings. In addition, design shows detail of its flow with outcomes of past leading trend which was re-created shape. On the other hand, undeveloped cultures such as folk, historical, and unique cultures attract design leaders as it is. This research would make good relationship between designers and customers regarding the newly started international trend of design. Hereby I research with the method to reclassify the image of vocabulary from the image scale extract. It remains as a task to resolve ambiguous, complex and neutral expression for better understanding and definite analysis method to the public.

A Matrix-Based Graph Matching Algorithm with Application to a Musical Symbol Recognition (행렬기반의 정합 알고리듬에 의한 음악 기호의 인식)

  • Heo, Gyeong-Yong;Jang, Kyung-Sik;Jang, Moon-Ik;Kim, Jai-Hie
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.8
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    • pp.2061-2074
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    • 1998
  • In pattern recognition and image analysis upplications, a graph is a useful tool for complex obect representation and recognition. However it takes much time to pair proper nodes between the prototype graph and an input data graph. Futhermore it is difficult to decide whether the two graphs in a class are the same hecause real images are degradd in general by noise and other distortions. In this paper we propose a matching algorithm using a matrix. The matrix is suiable for simple and easily understood representation and enables the ordering and matching process to be convenient due to its predefined matrix manipulation. The nodes which constitute a gaph are ordered in the matrix by their geometrical positions and this makes it possible to save much comparison time for finding proper node pairs. for the classification, we defined a distance measure thatreflects the symbo's structural aspect that is the sum of the mode distance and the relation distance; the fornet is from the parameters describing the node shapes, the latter from the relations with othes node in the matrix. We also introduced a subdivision operation to compensate node merging which is mainly due t the prepreocessing error. The proposed method is applied to the recognition of musteal symbols and the result is given. The result shows that almost all, except heavily degraded symbols are recognized, and the recognition rate is approximately 95 percent.

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A Building and Application of Enterprise Ontology with $Prot{\acute{e}}g{\acute{e}}$ - Representation and Analysis of Shipbuilding Process - ($Prot{\acute{e}}g{\acute{e}}$를 이용한 기업 온톨로지 기반 구축 및 활용 -조선 건조공정 표현과 분석 -)

  • Park, Ji-Hyun;Yang, Jae-Gun;Bae, Jae-Hak J.
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.3
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    • pp.27-39
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    • 2009
  • This paper describes a case study on an enterprise ontology(30) based analysis and representation of the production operation in shipbuilding. The production operation consists of steel fabrication, assembly, election, launching, sea trial and delivery process. We represent and analyze the steel fabrication process and the piping design business of the assembly process among them. First, we build an ontology on concepts of steel fabrication process and the piping design business of assembly process. And then we merge it with the original EO. We represent each process and analyze current state of production process with the merged EO and $Prot{\acute{e}}g{\acute{e}}$ plug-ins. Moreover, we can analyze dependency relations among the workflow elements. Through the case study, we have found the effectiveness of EO in business management and process management in complex heavy industries.

BoF based Action Recognition using Spatio-Temporal 2D Descriptor (시공간 2D 특징 설명자를 사용한 BOF 방식의 동작인식)

  • KIM, JinOk
    • Journal of Internet Computing and Services
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    • v.16 no.3
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    • pp.21-32
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    • 2015
  • Since spatio-temporal local features for video representation have become an important issue of modeless bottom-up approaches in action recognition, various methods for feature extraction and description have been proposed in many papers. In particular, BoF(bag of features) has been promised coherent recognition results. The most important part for BoF is how to represent dynamic information of actions in videos. Most of existing BoF methods consider the video as a spatio-temporal volume and describe neighboring 3D interest points as complex volumetric patches. To simplify these complex 3D methods, this paper proposes a novel method that builds BoF representation as a way to learn 2D interest points directly from video data. The basic idea of proposed method is to gather feature points not only from 2D xy spatial planes of traditional frames, but from the 2D time axis called spatio-temporal frame as well. Such spatial-temporal features are able to capture dynamic information from the action videos and are well-suited to recognize human actions without need of 3D extensions for the feature descriptors. The spatio-temporal BoF approach using SIFT and SURF feature descriptors obtains good recognition rates on a well-known actions recognition dataset. Compared with more sophisticated scheme of 3D based HoG/HoF descriptors, proposed method is easier to compute and simpler to understand.