• Title/Summary/Keyword: computer based estimation

Search Result 1,366, Processing Time 0.031 seconds

Objective Estimation of Velocity Streamfunction Field with Discretely Sampled Oceanic Data 1: with Application of Helmholtz Theorem (객관적 해석을 통한 속도 유선함수(streamfunction) 산출 1: 헬름홀쯔(Helmholtz) 정리의 응용)

  • 조황우
    • Journal of Environmental Science International
    • /
    • v.6 no.4
    • /
    • pp.323-333
    • /
    • 1997
  • An objective method for the generation of velocity streamfunction is presented for dealing with discretely sampled oceauc data. The method treats a Poisson equation (forced by vorticity) derived from Helmholtz theorem In which streamfunction is obtained by isolating the non-divergent part of the two-dimensional flow field. With a mixed boundary condition and vorticity field estimated from observed field, the method Is Implemented over the Texas-Louisiana show based on the current meter data of the Texas-Louisiana Shelf Circulation and Transport Processes Study (LATEX) measured at 31 moorings for 32 months (April 1992 - November 1994). The resulting streamfunction pattern is quote consistent with observations. The streamfunction field by this method presents an opportunity to initiauze and to verier computer models for local forecasts of enoronmental flow conditions for ell spill, nutrient and plankton transports as well as opportuuty to understand shelf-wlde low-frequency currents.

  • PDF

3D Shape Reconstruction of Non-Lambertian Surface (Non-Lambertian면의 형상복원)

  • 김태은;이말례
    • Journal of Korea Multimedia Society
    • /
    • v.1 no.1
    • /
    • pp.26-36
    • /
    • 1998
  • It is very important study field in computer vision 'How we obtain 3D information from 2D image'. For this purpose, we must know position of camera, direction of light source, and surface reflectance property before we take the image, which are intrinsic information of the object in the scene. Among them, surface reflectance property presents very important clues. Most previous researches assume that objects have only Lambertian reflectance, but many real world objects have Non-Lambertian reflectance property. In this paper the new method for analyzing the properties of surface reflectance and reconstructing the shape of object through estimation of reflectance parameters is proposed. We have interest in Non-Lambertian reflectance surface that has specular reflection and diffuse reflection which can be explained by Torrance-Sparrow model. Photometric matching method proposed in this paper is robust method because it match reference image and object image considering the neighbor brightness distribution. Also in this thesis, the neural network based shaped reconstruction method is proposed, which can be performed in the absence of reflectance information. When brightness obtained by each light is inputted, neural network is trained by surface normal and can determine the surface shape of object.

  • PDF

A Viewer Preference Model Based on Physiological Feedback (CogTV를 위한 생체신호기반 시청자 선호도 모델)

  • Park, Tae-Suh;Kim, Byoung-Hee;Zhang, Byoung-Tak
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.24 no.3
    • /
    • pp.316-322
    • /
    • 2014
  • A movie recommendation system is proposed to learn a preference model of a viewer by using multimodal features of a video content and their evoked implicit responses of the viewer in synchronized manner. In this system, facial expression, body posture, and physiological signals are measured to estimate the affective states of the viewer, in accordance with the stimuli consisting of low-level and affective features from video, audio, and text streams. Experimental results show that it is possible to predict arousal response, which is measured by electrodermal activity, of a viewer from auditory and text features in a video stimuli, for estimating interestingness on the video.

Some Results from a Sample Survey on the Use of Moxibustion Therapeutics in Korea (국내 뜸요법 사용실태에 관한 표본조사 결과)

  • Kim, Sun-Woong;Hong, Sung-Joon;Park, So-Hyung;Jung, Chan-Yung;Yoon, Eun-Hye;Lee, Seung-Deok
    • Journal of Acupuncture Research
    • /
    • v.27 no.2
    • /
    • pp.115-121
    • /
    • 2010
  • Objectives : Based on a national sample survey, we present an analysis of the current situation in the use of moxibustion therapeutics by qualified medical practitioners in Korea. Methods : The survey population of 11,737 hospitals is stratified by administrative regions, and 331 of them are randomly selected from the list of hospitals. The same number of Korean medical doctors is interviewed under the computer-assisted telephone interviewing(CATI) system. The bound on the error of estimation is ${\pm}\;5.0%$ point. Results : Of the 331 Korean medical doctors surveyed, 69% have used moxibustion therapy for remedial treatment. About half of those doctors have employed the therapy for their patients over 30%. The average number of acupuncture points per treatment using the therapy mostly ranges 1 between 5. The percent of practitioners, who have the number of average minutes less than 20 in treatment, is 74%. The number of practitioners who primarily use modified moxibustion is 4 times as many as that of those using traditional moxibustion. Conclusions : Considering the survey results, if the laser heater, alternative to conventional moxibustion, which not only gives high thermal effect but also reduces both the users inconvenience and side effects, are developed, it may benefit more patients as well as Korean medical doctors.

Real Time Eye and Gaze Tracking (실시간 눈과 시선 위치 추적)

  • Cho, Hyeon-Seob;Kim, Hee-Sook
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.6 no.2
    • /
    • pp.195-201
    • /
    • 2005
  • This paper describes preliminary results we have obtained in developing a computer vision system based on active IR illumination for real time gaze tracking for interactive graphic display. Unlike most of the existing gaze tracking techniques, which often require assuming a static head to work well and require a cumbersome calibration process for each person, our gaze tracker can perform robust and accurate gaze estimation without calibration and under rather significant head movement. This is made possible by a new gaze calibration procedure that identifies the mapping from pupil parameters to screen coordinates using the Generalized Regression Neural Networks (GRNN). With GRNN, the mapping does not have to be an analytical function and head movement is explicitly accounted for by the gaze mapping function. Furthermore, the mapping function can generalize to other individuals not used in the training. The effectiveness of our gaze tracker is demonstrated by preliminary experiments that involve gaze-contingent interactive graphic display.

  • PDF

Efficient Distributed Video Coding System and Performance Analysis Using Lapped Transform (Lapped Transform을 이용한 효율적인 분산 동영상 부호화 시스템 및 성능해석)

  • Kang, Soo-Kyung;Lee, Chang-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.36 no.9C
    • /
    • pp.564-572
    • /
    • 2011
  • Distributed video coding (DVC) system has been proposed to reduce encoder complexity by using the correlation of frames in decoders. Since the block based motion estimation operation is not performed in the encoder of DVC system, lapped transforms, in which adjacent two blocks are transformed into one block, can be efficiently used in the DVC system. In this paper, an efficient DVC system using lapped transforms is proposed. The overlapped block motion compensated interpolation is used to produce side information, and the corresponding correlation noise between original Wyner-Ziv frame and side information is modeled. Extensive computer simulations show that the proposed DVC system outperforms conventional DVC systems.

Formation of Acid Mine Drainage and Pollution of Geological Environment Accompanying the Sulfidation Zone of Nonmetallic Deposits: Reaction Path Modeling on the Formation of AMD of Tongnae Pyrophyllite Mine (비금속광상의 황화광염대에 수반되는 산성광산배수의 형성과 지질환경의 오염 : 동래납석광산 산성광산배수의 형성에 관한 반응경로 모델링)

  • 박맹언;성규열;고용전
    • Economic and Environmental Geology
    • /
    • v.33 no.5
    • /
    • pp.405-415
    • /
    • 2000
  • This study was carried out to understand the formation of acid mine drainage (AMD) by pyrophyllite (so-called Napseok)-rainwater interaction (weathering), dispersion patterns of heavy metals, and patterns of mixing with non-polluted water in the Tongnae pyrophyllite mine. Based on the mass balance and reaction path modeling, using both the geochemistry of water and occurrence of the secondary minerals (weathering products), the geochemical evolution of AMD was simulated by computer code of SOLVEQ and CHILLER. It shows that the pH of stream water is from 6.2 to 7.3 upstream of the Tongnae mine. Close to the mine, the pH decreases to 2. Despite being diluted with non-polluted tributaries, the acidity of mine drainage water maintains as far as downstream. The results of modeling of water-rock interaction show that the activity of hydrogen ion increases (pH decreases), the goncentration of ${HCO_3}^-$ decreases associated with increasing $H^+$ activity, as the reaction is processing. The concentration of ${SO_4}^{2-}$first increases minutely, but later increases rapidly as pH drops below 4.3. The concentrations of cations and heavy metals are controlled by the dissolution of reactants and re-dissolution of derived species (weathering products) according to the pH. The continuous adding of reactive minerals, namely the progressively larger degrees of water-rock interaction, causes the formation of secondary minerals in the following sequence; goethite, then Mn-oxides, then boehmite, then kaolinite, then Ca-nontronite, then Mgnontronite, and finally chalcedony. The results of reaction path modeling agree well with the field data, and offer useful information on the geochemical evolution of AMD. The results of reaction path modeling on the formation of AMD offer useful information for the estimation and the appraisal of pollution caused by water-rock interaction as geological environments. And also, the ones can be used as data for the choice of appropriate remediation technique for AMD.

  • PDF

A Study on the Development of Hybrid-typed Education Model for PO6 and PO7 Estimation (복합학제적 능력 및 의사소통 능력과 관련된 학습성과 평가를 위한 융합교육형 모델 개발에 관한 연구)

  • Kim, Eun-Joo;Cho, Young-Im;Do, Seung-Lee
    • Journal of Engineering Education Research
    • /
    • v.13 no.6
    • /
    • pp.132-142
    • /
    • 2010
  • The purpose of this study is to suggest the assessment method for PO6(teamwork) and PO7(communication skill), one of the most important assessment items in engineering accreditation. In this paper, we used the assessment criteria of Rubric, to empirically measure the teamwork and communication skill. Teamwork and communication skill (PO6, PO7) are the most critical social competences in modern society. Numerous studies on education showed that teamwork and communication skill can be enhanced through learning. We, therefore, need to investigate teamwork and communication skill in terms of education. However, research on the assessment method of the engineering accreditation, based on educational view is scarce. In this study, we suggest the assessment criteria of Rubric for PO6 and PO7 with the perspective of the education. We also tried to apply the developed criteria to the related subjects.

  • PDF

Estimation of vitamin K intake in Koreans and determination of the primary vitamin K-containing food sources based on the fifth Korean National Health and Nutrition Examination Survey (2010-2011)

  • Kim, Eun-Soo;Kim, Mi-Sung;Na, Woo-Ri;Sohn, Cheong-Min
    • Nutrition Research and Practice
    • /
    • v.7 no.6
    • /
    • pp.503-509
    • /
    • 2013
  • There is little information on dietary vitamin K intake and nutritional status of daily requirements of vitamin K in Korea. The objective of this study was to investigate the vitamin K intake and major food sources of Vitamin K in Koreans. The survey data from the 2010-2011 Korean National Health and Nutrition Examination Survey of 7,792 subjects (aged 19-64 years) were examined. Total vitamin K intake was calculated from 24-hour dietary recall using a vitamin K food database, Computer Aided Nutritional analysis Program and the United States Department of Agriculture database. The geometric mean of vitamin K was estimated as $322.40{\pm}6.33ug/day$ for men and $271.20{\pm}4.92ug/day$ for women. Daily vitamin K intake increased significantly with age (p for trend < 0.001). The main food source of vitamin K was vegetables (72.84%), including cabbage kimchi (19.26%), spinach (17.38%), sesame leaves (7.11%), radish leaves (6.65%), spring onions (6.28%), and laver (4.82%), followed by seaweed, seasonings, and fat and oils. We observed that the vitamin K intake of Koreans was relatively higher than that reported by other studies in Western countries and differed depending on age.

Using Spatial Data and Land Surface Modeling to Monitor Evapotranspiration across Geographic Areas in South Korea (공간자료와 지면모형을 이용한 면적증발산 추정)

  • Yun J. I.;Nam J. C.;Hong S. Y.;Kim J.;Kim K. S.;Chung U.;Chae N. Y.;Choi T. J
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.6 no.3
    • /
    • pp.149-163
    • /
    • 2004
  • Evapotranspiration (ET) is a critical component of the hydrologic cycle which influences economic activities as well as the natural ecosystem. While there have been numerous studies on ET estimation for homogeneous areas using point measurements of meteorological variables, monitoring of spatial ET has not been possible at landscape - or watershed - scales. We propose a site-specific application of the land surface model, which is enabled by spatially interpolated input data at the desired resolution. Gyunggi Province of South Korea was divided into a regular grid of 10 million cells with 30m spacing and hourly temperature, humidity, wind, precipitation and solar irradiance were estimated for each grid cell by spatial interpolation of synoptic weather data. Topoclimatology models were used to accommodate effects of topography in a spatial interpolation procedure, including cold air drainage on nocturnal temperature and solar irradiance on daytime temperature. Satellite remote sensing data were used to classify the vegetation type of each grid cell, and corresponding spatial attributes including soil texture, canopy structure, and phenological features were identified. All data were fed into a standalone version of SiB2(Simple Biosphere Model 2) to simulate latent heat flux at each grid cell. A computer program was written for data management in the cell - based SiB2 operation such as extracting input data for SiB2 from grid matrices and recombining the output data back to the grid format. ET estimates at selected grid cells were validated against the actual measurement of latent heat fluxes by eddy covariance measurement. We applied this system to obtain the spatial ET of the study area on a continuous basis for the 2001-2003 period. The results showed a strong feasibility of using spatial - data driven land surface models for operational monitoring of regional ET.