• Title/Summary/Keyword: Large Object

Search Result 1,184, Processing Time 0.026 seconds

Acquisition and Accuracy Assessment of topographic information of inaccessible areas (위성영상을 이용한 비접근지역의 지형정보 획득 및 정확도 평가)

  • 고종식;최윤수;김욱남;이상준
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2004.11a
    • /
    • pp.393-398
    • /
    • 2004
  • It is transformed map data of different coordinate system into unique system and We triedto make topographic map on non-accessible area. We transformed Russian map coordinates(Krassovsky, G-K projection) intoWGS-84, TM projection and assessed accuracy. The RMSE(in East and West bearings : ${\pm}$13.67m, in North and South bearings : ${\pm}$14.67m) using only SCP(Survey Control Point) is more accurate than that(in East and West bearings : ${\pm}$24.26m, in North and South bearings : ${\pm}$25.32m) using SCP, intersection of road, bridge. Exterior orientation parameters are estimated using rigorous modelling and GCPs are classified with SCP, intersection of road, bridge. Rigorous modelling is performed with each classified GCP. The modelling result usingonly SCP(in East and West bearings : ${\pm}$13.53m, in North and South bearings : ${\pm}$14.22m) is more accurate than that using intersection of road(in East and West bearings : ${\pm}$16.l1m, in North and South bearings: ${\pm}$23.85m), bridge(in East and West bearings : ${\pm}$17.21m, in North and South bearings : ${\pm}$21.82m). The results means that SCP is more accurate than intersection of road, bridge because of edit to generate map. therefore, SCP is suitable for object of GCP in paper map(1:50,000). Geographic information on non-accessible area and analysis is performed. The results of stereoscopic plotting is well matched old map data on road, railroad but, many objects are generally editted. It is possible to update on new objects(building, tributary ‥‥etc). Ability of description using SPOT-5(stereo) is more than features and items included in 1:50,000 topographic map. Therefore, it is possible to make large scale map than 1:50,000 topographic map using SPOT-5 imagery. But, there are many problems(accurate GCPs, obtain of high resolution stereoscopic satellite imagery in a period ‥‥ etc) to make topographic map on non-accessible area. It is actually difficult to solve these problems. therefore, it is possible to update 1:50,000 topographic map in part of topographic map generation.

  • PDF

Accuracy Evaluation by Point Cloud Data Registration Method (점군데이터 정합 방법에 따른 정확도 평가)

  • Park, Joon Kyu;Um, Dae Yong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.38 no.1
    • /
    • pp.35-41
    • /
    • 2020
  • 3D laser scanners are an effective way to quickly acquire a large amount of data about an object. Recently, it is used in various fields such as surveying, displacement measurement, 3D data generation of objects, construction of indoor spatial information, and BIM(Building Information Model). In order to utilize the point cloud data acquired through the 3D laser scanner, it is necessary to make the data acquired from many stations through a matching process into one data with a unified coordinate system. However, analytical researches on the accuracy of point cloud data according to the registration method are insufficient. In this study, we tried to analyze the accuracy of registration method of point cloud data acquired through 3D laser scanner. The point cloud data of the study area was acquired by 3D laser scanner, the point cloud data was registered by the ICP(Iterative Closest Point) method and the shape registration method through the data processing, and the accuracy was analyzed by comparing with the total station survey results. As a result of the accuracy evaluation, the ICP and the shape registration method showed 0.002m~0.005m and 0.002m~0.009m difference with the total station performance, respectively, and each registration method showed a deviation of less than 0.01m. Each registration method showed less than 0.01m of variation in the experimental results, which satisfies the 1: 1,000 digital accuracy and it is suggested that the registration of point cloud data using ICP and shape matching can be utilized for constructing spatial information. In the future, matching of point cloud data by shape registration method will contribute to productivity improvement by reducing target installation in the process of building spatial information using 3D laser scanner.

Clinical Usefulness on K-MBI for Decision of Driving Rehabilitation Period in Patients with Stroke: A pilot study (뇌졸중 환자의 운전재활 시기 결정을 위한 K-MBI의 임상적 유용성: 예비 연구)

  • Park, Myoung-Ok
    • Journal of rehabilitation welfare engineering & assistive technology
    • /
    • v.11 no.2
    • /
    • pp.91-98
    • /
    • 2017
  • Background & Object: Basic daily activity screening tool such as the Modified Barthel Index (MBI) has been used commonly in rehabilitation clinic and community based rehabilitation setting. Previous studies have shown the significant relations between the level of daily activities and driving ability on stroke or elderly people. However, there is a lack of studies to investigate the usefulness of MBI on prediction of driving ability for stroke patient. This study was to predict driving abilities of stroke survivor using Korean version Modified Barthel Index (K-MBI). Methods: A sample of 48 patients with stroke in rehabilitation hospital was recruited. All participants were tested level of basic daily activities using K-MBI. The driving ability of participants was tested using virtual reality driving simulator. The predictive validity was calculated of the K-MBI among pass or fail group of driving simulator test using receiver operating characteristics curves. Results: The cut-off score of >86.5 on the K-MBI is proper sensitivity to predict on driving performance ability. Conclusion: This pilot result offers clinical reference to therapists and caregivers for reasoning on driving recommendation period during rehabilitation stage of stroke survivors. Further studies need to identify prediction using real on-road test in a large population group.

Development of the Imaging Optical System for the 545 nm Fluorescent Plate of X-ray (X선용 545 nm 형광판 결상광학계 개발)

  • Lee, Dong-Hee
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.13 no.2
    • /
    • pp.17-22
    • /
    • 2008
  • To develop an imaging optical system for the 545 nm fluorescent plate of X-ray. Methods: We designed and manufactured a new imaging optical system for the 545 nm fluorescent plate of X-ray by Sigma 2000 program after deciding the design comparison standards referred to Canon CX2-70 model. Results: The characteristics of the new imaging optical system for the 545 nm fluorescent plate of X-ray have the magnification of -0.225x, the image field size of $90mm{\times}90mm$, and the 0.033 mm resolution line width at the 30% MTF value criterion. These mean that the new model has a capability of deciphering for the more large screen and the resolution of deciphering is superior to that of Canon CX2-70 model. Also the image side NA (-0.196) of the new model is about $\sqrt{2}$ times than that (-0.139) of CX2-70 and the object side NA (0.044) of the new model is about 2 times than that (0.022) of CX2-70. These mean that the sensitivity of the film in the new design model is able to be increased to about 4 times and there is the possibility of reducing the bombed time of X-ray to 1/4 times. Conclusions: We could design and manufacture the imaging optical system for the 545 nm fluorescent plate of X-ray having the possibility of reducing the bombed time of X-ray to 1/4 times in comparision to Canon CX2-70 model, the characteristics of which have the image field size of $90mm{\times}90mm$ and the MTF of 30% or more at 15 lines/mm criterion.

  • PDF

Odysseus/m: a High-Performance ORDBMS Tightly-Coupled with IR Features (오디세우스/IR: 정보 검색 기능과 밀결합된 고성능 객체 관계형 DBMS)

  • Whang Kyu-Young;Lee Min-Jae;Lee Jae-Gil;Kim Min-Soo;Han Wook-Shin
    • Journal of KIISE:Computing Practices and Letters
    • /
    • v.11 no.3
    • /
    • pp.209-215
    • /
    • 2005
  • Conventional ORDBMS vendors provide extension mechanisms for adding user-defined types and functions to their own DBMSs. Here, the extension mechanisms are implemented using a high-level interface. We call this technique loose-coupling. The advantage of loose-coupling is that it is easy to implement. However, it is not preferable for implementing new data types and operations in large databases when high Performance is required. In this paper, we propose to use the notion of tight-coupling to satisfy this requirement. In tight-coupling, new data types and operations are integrated into the core of the DBMS engine. Thus, they are supported in a consistent manner with high performance. This tight-coupling architecture is being used to incorporate information retrieval(IR) features and spatial database features into the Odysseus/IR ORDBMS that has been under development at KAIST/AITrc. In this paper, we introduce Odysseus/IR and explain its tightly-coupled IR features (U.S. patented). We then demonstrate a web search engine that is capable of managing 20 million web pages in a non-parallel configuration using Odysseus/IR.

Color Correction Method of CIS Digital Camera for Mobile Phone (휴대폰용 CIS 디지털 카메라의 컬러 보정법)

  • Kim Eun-Su;Jang Soo-Wook;Lee Sung-Hak;Han Chan-Ho;Jung Tae-Young;Sohng Kyu-Ik
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.43 no.4 s.310
    • /
    • pp.9-18
    • /
    • 2006
  • In the digital camera system, CMOS image sensor (CIS) is widely used because its size and weight become smaller and power consumption becomes lower. However, there are common problems that colors of the recorded image do not match those of the photographed object and that spectral sensitivity of the CIS used in different cameras varies largely in each case. Therefore, color correction is needed because the spectral sensitivity of the CIS in each color is neither the same color component for most standard colors nor the appropriate color representation for any output devices. In the conventional method, a color correction is empirically obtained by a large number of iterative experiments, but the result is not so satisfied. In this paper, a new method to obtain the efficient color correction matrix for digital camera using CIS is proposed. We obtain camera transfer matrix under the certain white-balance point, and color correction matrix that makes the transfer characteristic of digital camera close to the transfer characteristic of ideal camera is obtained. The experimental results show that the transfer characteristic of digital camera by the proposed method is close to that of the ideal camera. In addition, the image quality of pictures of digital camera using the proposed method is dramatically improved.

Analysis on the Image and Visual Preference of Bridge Landscapes - A Focus on Background Landscape and Bridge Type - (교량경관의 이미지 및 시각적 선호도 분석 - 배경경관 및 교량형태를 중심으로 -)

  • Jung, Sung-Gwan;Chae, So-Jung;Kim, Kyung-Tae;Lee, Woo-Sung;Park, Kyung-Hun;You, Ju-Han
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.35 no.5
    • /
    • pp.82-91
    • /
    • 2007
  • Currently, bridges are regarding as the structure with formative, scenic and environmental values more than their function as simple passageways. Because an attempt to work on the diversity of the bridge types and installation of the large structures on bridge are part of the project of the regional amenity enterprises, a study that harmonizes bridges with landscape is needed at this point in time. This background can influence the direction of bridge landscapes that considers local features by analysis of visual preferences on a bridge simulated scene. The results were as follows: analyzing the change of the simulated landscape image, forest landscape are damaged by the input of a bridge which was natural, harmonic and intimate. On the other hand, when a bridge was inserted into the ocean landscape, it was thought to improve the ocean landscape, especially, upper part form of arch bridge various or suspension bridge were improved in polished and various image. The insertion of a bridge into an urban landscape change from a negative image to a beautiful, harmonic and attractive image. The intimate, harmonic and natural image of a rural landscape was damaged by inserting a bridge. As analysis result about change of landscape preference by input of bridge, there is difference between before and after as input the bridge, and bridge influences as main object in the simulated scene. Visual preference was the highest in the ocean landscape, and the lowest in the suspension bridge in the rural landscape. The complicated shape of bridge follows on the background type difference certainly appear. Thee simulated scene preference except the urban landscape of the simulated scene fell generally Especially, fall of preference of girder bridge in the forest and ocean landscape, suspension bridge in the rural landscape appeared notedly.

Design of Mobile Agent Model Supporting the Intelligent Path Search (지능형 경로 탐색을 지원하는 이동 에이전트 모델 설계)

  • Ko, Hyun;Kim, Kwang-Myoung;Lee, Yon-Sik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2002.11a
    • /
    • pp.550-554
    • /
    • 2002
  • In this paper, we design the CORBA-based Mobile-Agent Model (CMAM) which has the capability of the efficient work processing in distributed environment through sensing network traffic and searching the optimal path for migration nodes of mobile agent. In case existing mobile agent model is given various works from user, the network overhead and traffic are increased by increasing of execution module size. Also, if it happens a large quantity of traffics due to migration of nodes according to appointment of the passive host(node) muting schedule by user, it needs much cost for node search time by traffic. Therefore, in this paper, we design a new mobile agent model that assures the reliability of agent's migration through dynamic act on the specific situation according to appointment of the active routing schedule and can minimize agent's work processing time through optimal path search. The proposed model assigns routing schedule of the migration nodes actively using an extended MAFFinder. Also, for decreasing overhead of network by agent's size, it separated by mobile agent including oかy agent calling module and push agent with work executing module based on distributed object type of CORBA. Also, it can reduce the required time for round works of mobile agent through the optimal path search of migration nodes.

  • PDF

The Population Characteristic of First Record on the Cottus koreanus from Hoam Stream, Korea (호암천에서 처음 채집된 둑중개 개체군의 특성)

  • Byeon, Hwa-Keun;Lee, Byeong-Ryong
    • Korean Journal of Environment and Ecology
    • /
    • v.31 no.2
    • /
    • pp.166-173
    • /
    • 2017
  • Morphological and population characteristics of the Cottus koreanus were investigated at Hoam stream from October 2015 and April 2016. This is the first record on C. koreanus not only from Hoam stream (the upstream region of Daejong stream, Gyeongsangbuk-do Gyeongju-si Yangbuk-myeon Hoam-ri) but also from the stream flowing into the Samcheogosip stream, in the southern part of East Sea, Korea. The distribution of C. koreanus ranged from Girim temple to Yongyeon waterfall, about 1.2 km, and the water surface were about $3,600m^2$. The population size was assumed to 1,656 individual number, 46 object per $100m^2$. The morphometric characteristics of C. koreanus in the Hoam stream and the Han river are very similar except that the population at Hoam stream shorter head length, ventral fin ray length, pectoral fin ray length and mouth width when compared with the population at Han river. Other than that, the two populations showed the same meristic characters. Frequency analysis of total length indicated that the group with 40~59 mm in total length was one year old, the 60~79 mm was two years old, and the group over 80 mm was three years old. The average number of eggs in the ovaries was estimated as 361 (239~468) per matured female. The number of matured eggs size in ovaries was $2.6{\pm}0.21$ (23.~3.1) mm and this species was large eggs type. Calculation of the length-weight relation of C. koreanus showed the value of constant a as 0.00001 and b as 3.01, and the Condition factor (K) was 1.26 an on average.

Weighted Census Transform and Guide Filtering based Depth Map Generation Method (가중치를 이용한 센서스 변환과 가이드 필터링 기반깊이지도 생성 방법)

  • Mun, Ji-Hun;Ho, Yo-Sung
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.54 no.2
    • /
    • pp.92-98
    • /
    • 2017
  • Generally, image contains geometrical and radiometric errors. Census transform can solve the stereo mismatching problem caused by the radiometric distortion. Since the general census transform compares center of window pixel value with neighbor pixel value, it is hard to obtain an accurate matching result when the difference of pixel value is not large. To solve that problem, we propose a census transform method that applies different 4-step weight for each pixel value difference by applying an assistance window inside the window kernel. If the current pixel value is larger than the average of assistance window pixel value, a high weight value is given. Otherwise, a low weight value is assigned to perform a differential census transform. After generating an initial disparity map using a weighted census transform and input images, the gradient information is additionally used to model a cost function for generating a final disparity map. In order to find an optimal cost value, we use guided filtering. Since the filtering is performed using the input image and the disparity image, the object boundary region can be preserved. From the experimental results, we confirm that the performance of the proposed stereo matching method is improved compare to the conventional method.