• Title/Summary/Keyword: Continuation method

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Rendering Method of Light Environment Based on Modeling of Physical Characteristic (물리적 특성 모델링에 기반한 라이팅 환경의 랜더링 기법)

  • Lee, Myong-Young;Lee, Cheol-Hee;Ha, Yeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.43 no.6 s.312
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    • pp.46-56
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    • 2006
  • In this paper, we propose an improved reproduction algorithm for a realistic image of the real scene based on the optical characteristics of the light sources and the materials at the lighting environment. This paper is continuation of the previous study to improve the modeling method of the light sources and the materials and apply this to the real rear lamp of automobile. The backward ray tracing method is first used to trace the light ray from a light source, and also considers the physical characteristics of object surfaces and geometric properties of light radiation to estimate accurately the light energy incoming toward to human eyes. For experiments and verification of the proposed method, the simulation results are compared with the measured light stimuli. Accordingly, the simulation results show that the proposed algorithm can estimate light energy well and reproduce the visually similar image with a scene incident on a sight of viewer.

Magnetic Investigation of the Yangsan Fault (양산 단층에 대한 자력탐사 연구)

  • Kwon, Byung-Doo;Lee, Ki-Won
    • Economic and Environmental Geology
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    • v.24 no.4
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    • pp.421-434
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    • 1991
  • Ground magnetic surveys were conducted at four areas where the Yangsan fault, the most prominent lineament in the Kyeongsang basin, appears to be passed through. For data processing, IGRF correction, upward continuation and reduction-to-the-pole were performed. The automatic inversion by using a matrix computation method, which takes the depth to bottom layer of the horizontal two layer structure as the model parameter, has been attempted to delineate the subsurface structure. Upward continuation of the surface magnetic map to the same level of the aeromagnetic survey (KIER, 1989) resulted in very similiar patterns to those of aeromagnetic data. Subsurface modeling of eight profile data show that the strike and dip of the Yangsan fault in study areas are $N6^{\circ}-15^{\circ}E$, and near vertical to somewhat eastward, repectively, despite of the local lithological contrast of each study area. It seems that the magnetic effect of faulting in the study area 1, which locates in the most northern part of the survey areas, is disturbed by that of igneous intrusion. At study area 2, the possibility of volcanic or igneous intrusion, which is 200-300 meters wide along the fault plane was presented. At study area 3, unlike other study areas, distinct fracture zone of 500-700 meters in width was revealed along the surface fault line. The andesitic rocks of the study area 4 have very high susceptibilities and the fault line on surface of this area was shifted about 500 meter eastward, as compared with the inferred fault line by the previous study.

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A Study on Four-year College Curriculum for the Education of Radiological Technology in Korea (방사선학과(放射線學科)의 4년제(年制) 대학(大學) 교육과정(敎育課程)에 대한 연구(硏究))

  • Choi, Jong-Hak;Lee, Sang-Suk;Kim, Young-Il;Kwon, Dal-Gwan;Kim, Heung-Tae;Lim, Han-Young
    • Journal of radiological science and technology
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    • v.18 no.2
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    • pp.87-102
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    • 1995
  • The education of radiologic technology began in the regular institute of higher education in Korea in 1963. Up to now from then, our education to bring up the radiologic technologists has developed greatly in quality and quantity, and now departments of radio-technology are founded in the 16 junior colleges in March, 1995. This study was done to verify the necessity and propriety to reform the education system of radiologic technology which was run as two or three year system of college curriculum for 32 years since 1963, and to search for the method to reform in the future. We got the following results from this research. 1. In the survey, on the desirable education year for radiologic technologists, 63.9 % of professors of department of radio-technology and 63.0 % of radiologic technologists chose the 4 year system, 27.9 % of professors and 34.6 % of radiologic technologists chose the 4 year system added to graduate school. 2. In the survey, on the future development of radiologic equipments and technique, 67.2 % of professors of department of radiologic technology and 86.4 % of radiologic technologists have a view of "revolutional development". Also, on the future tasks or roles of radiologic technologists 95.1% of professors and 94.9% of radiologic technologists have a view that "They will increase". 3. On the necessity of extension of education year to 4 years from 3 years, the factor is that development of medical technique and machinery and tools, advance of qualification of radiologic technologists, enlargement and specialization of the business of the radiologic technologists, ballance of education year with other medical sciences, international competitive power and cooperation of radiologic technology, and education continuation of the graduates of department of radiologic technology. 4. They suggested that in the 4 year curriculum of department of radiologic technology, clinical medicine, quality control of radiation and radiologic equipment, related subjects to the radiologic application and computer application should be enforced and clinical practice should be extended more. 5. On the device to found the 4 year college curriculum of radiologic technology, they suggested that first, 4 year curriculum should be founded through the variety of educational year, secondly, department of radiologic technology should be founded in the 4 year health sciences college, thirdly, educational continuation of the radiologic technologists should be systematized on the basis of life-long education.

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A STUDY OF Q-CONTIGUOUS FUNCTION RELATIONS

  • Harsh, Harsh Vardhan;Kim, Yong Sup;Rakha, Medhat Ahmed;Rathie, Arjun Kumar
    • Communications of the Korean Mathematical Society
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    • v.31 no.1
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    • pp.65-94
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    • 2016
  • In 1812, Gauss obtained fifteen contiguous functions relations. Later on, 1847, Henie gave their q-analogue. Recently, good progress has been done in finding more contiguous functions relations by employing results due to Gauss. In 1999, Cho et al. have obtained 24 new and interesting contiguous functions relations with the help of Gauss's 15 contiguous relations. In fact, such type of 72 relations exists and therefore the rest 48 contiguous functions relations have very recently been obtained by Rakha et al.. Thus, the paper is in continuation of the paper [16] published in Computer & Mathematics with Applications 61 (2011), 620.629. In this paper, first we obtained 15 q-contiguous functions relations due to Henie by following a different method and then with the help of these 15 q-contiguous functions relations, we obtain 72 new and interesting q-contiguous functions relations. These q-contiguous functions relations have wide applications.

Optimal Perilune Altitude of Lunar Landing Trajectory

  • Cho, Dong-Hyun;Jeong, Bo-Young;Lee, Dong-Hun;Bang, Hyo-Choong
    • International Journal of Aeronautical and Space Sciences
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    • v.10 no.1
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    • pp.67-74
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    • 2009
  • In general, the lunar landing stage can be divided into two distinct phases: de-orbit and descent, and the descent phase usually comprises two sub-phases: braking and approach. And many optimization problems of minimal energy are usually focused on descent phases. In these approaches, the energy of de-orbit burning is not considered. Therefore, a possible low perilune altitude can be chosen to save fuel for the descent phase. Perilune altitude is typically specified between 10 and 15km because of the mountainous lunar terrain and possible guidance errors. However, it requires more de-orbit burning energy for the lower perilune altitude. Therefore, in this paper, the perilune altitude of the intermediate orbit is also considered with optimal thrust programming for minimal energy. Furthermore, the perilune altitude and optimal thrust programming can be expressed by a function of the radius of a parking orbit by using continuation method and co-state estimator.

A study on the Interactive relationship between the public space and the public art - Focused on the Works of Daniel Buren - (현대 공공 공간과 공공미술의 상호 작용에 관한 연구 - 다니엘 뷰렌의 작품을 중심으로 -)

  • Kim, Hyun-Jung
    • Korean Institute of Interior Design Journal
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    • v.16 no.2 s.61
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    • pp.147-154
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    • 2007
  • This study places a great emphasis on the approaches to the space environment we inhabit, which I hope will contribute to generating a number of creative possibilities. Looking into 'site-specificity' which is characteristic by public art in public space method based on Daniel Buren's works 'in situ', this study analyze the relationship between the public space and works of art as a perspective of public art. The characteristics of his 'in situ' works that intervened works exist as space consisting of serial factors not simply art-object, and they suggest 'site Is a work'. The case study of Daniel Buren's public art project represented the results, the site marketing and serves as a guideline for the future of true Art/Space experiments. This study verifies the need for the arts and the space to work together in order to develop more creative and conceptual approaches to innovation and presentation. This cooperation is the continuation of space design by other means.

A Study on the Characteristic of Raumplan based on the Architectural Thought of Adolf Loos (아돌프 로스의 건축사상에 기초한 라움플란의 특성에 관한 연구)

  • Park, Chan-Il
    • Korean Institute of Interior Design Journal
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    • v.17 no.6
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    • pp.30-40
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    • 2008
  • Adolf Loos showed important directionality in the thought of modem culture and architecture. The thought about the architecture of Adolf Loos was gathered by "Raumplan". It is the solution of the plan in space. But the concept and method of the "Raumplan" had not been synthesized until near the end of Loos's life. Loos's first reference to the "Raumplan" appears in 1929. I think that "Raumplan" became the solution of the plan in space with a formation process of the thought about the architecture and culture of Adolf Loos. Therefore, the purpose of this paper derived a characteristic of "Raumplan" from the relations between the architectural thought of Adolf Loos and "Raumplan". The processes of the study are as follows. (1)Consideration about the growth background of Adolf Loos and the social situation of Vienna. (2)Analysis about architecture and the cultural critic of Adolf Loos. (3)Analysis of "Raumplan" based on architectural thought of Adolf Loos. As a result, I got the four characteristics of "Raumplan" as follows. (1) Separation and continuation of "Raum". (2) Fragment of "Raum". (3) Overlay and transmission by the axis of multiplex eyes. (4) Structural adjustment of the "Raum" by Hierarchy. Finally, I understood the architecture which Adolf Loos pursued in "Raumplan" had a high function and contained the clear meaning and contents which had practical use and economic value, and it were not a results of the simple logic.

A study of Robot Programming Curriculum based on Storytelling (스토리텔링 기반 로봇 프로그래밍 교육과정 연구)

  • Lee, Jae-Inn;Sung, Young-Hoon
    • 한국정보교육학회:학술대회논문집
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    • 2011.01a
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    • pp.15-22
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    • 2011
  • Most of the robot programming curriculums consists mainly of understanding robot programming language and learning a simple grammatical sentences rather than logical problem solving process, these curriculums impose a burden on childrens' learning. Storytelling offers opportunities for continuation of childrens' positive learning motivation to practice symbolic manipulations, hold multiple abstract concepts in their heads, and create meaning between these ideas. In this paper, to overcome the difficulty of robot programming curriculum in elementary school and find teaching method which derives the childrens' motivation, we used storytelling in study of our robot programming curriculum.

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Parameter Tuning Algorithm for Sliding Mode Control (슬라이딩 모드 제어를 위한 인자 튜닝 알고리듬)

  • 류세희;박장현
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.438-442
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    • 2003
  • For an efficient sliding mode control system stability and chattering avoidance should be guaranteed. A continuation method using boundary layer is well known as one solution for this. However since not only model uncertainties and disturbances but also control task itself is variable. it is practically impossible to set controller parameters - control discontinuity, control bandwidth, boundary layer thickness - in advance. In this paper first an adaptation law of control discontinuity is introduced to assure system stability and then fuzzy logic based tuning algorithm of design parameters is applied based on monitored performance indices of tracking error, control chattering, and model precision. In the end maximum control bandwidth not exciting unmodeled dynamics and minimum control discontinuity, boundary layer thickness making system stable and free of chattering are found respectively. This eliminates control chattering and enhances control accuracy as much as possible under given control situation. In order to demonstrate the validity of the proposed algorithm safe headway maintenance control for autonomous transportation system is simulated. The control results show that the proposed algorithm guarantees system stability all the time and tunes control parameters consistently and in consequence implements an efficient control in terms of both accuracy and actuator chattering.

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Three-dimensional analysis of the natural vibration of the three-layered hollow sphere with middle layer made of FGM

  • Akbarov, Surkay D.;Guliyev, Hatam H.;Yahnioglu, Nazmiye
    • Structural Engineering and Mechanics
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    • v.61 no.5
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    • pp.563-576
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    • 2017
  • This paper is a continuation of the investigations started in the paper by Akbarov, S.D., Guliyev, H.H and Yahnioglu, N. (2016) "Natural vibration of the three-layered solid sphere with middle layer made of FGM: three-dimensional approach", Structural Engineering and Mechanics, 57(2), 239-263, to the case where the three-layered sphere is a hollow one. Three-dimensional exact field equations of elastodynamics are employed for investigation and the discrete-analytical method is employed for solution of the corresponding eigenvalue problem. The FGM is modelled as inhomogeneous for which the modulus of elasticity, Poison's ratio and density vary continuously through the inward radial direction according to power law distribution. Numerical results on the natural frequencies are presented and discussed. These results are also compared with the corresponding ones obtained in the previous paper by the authors. In particular, it is established that for certain harmonics and for roots of certain order, the values of the natural frequency obtained for the hollow sphere can be greater (or less) than those obtained for the solid sphere.