• Title/Summary/Keyword: Map-Reduce

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Efficiency Algorithm of Multispectral Image Compression in Wavelet Domain (웨이브릿 영역에서 다분광 화상데이터의 효율적인 압축 알고리듬)

  • Ban, Seong-Won;Seok, Jeong-Yeop;Kim, Byeong-Ju;Park, Gyeong-Nam;Kim, Yeong-Chun;Jang, Jong-Guk;Lee, Geon-Il
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.38 no.4
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    • pp.362-370
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    • 2001
  • In this paper, we proposed multispectral image compression method using CIP (classified inter-channel prediction) and SVQ (selective vector quantization) in wavelet domain. First, multispectral image is wavelet transformed and classified into one of three classes considering reflection characteristics of the subband with the lowest resolution. Then, for a reference channel which has the highest correlation and the same resolution with other channels, the variable VQ is performed in the classified intra-channel to remove spatial redundancy. For other channels, the CIP is performed to remove spectral redundancy. Finally, the prediction error is reduced by performing SVQ. Experiments are carried out on a multispectral image. The results show that the proposed method reduce the bit rate at higher reconstructed image quality and improve the compression efficiency compared to conventional methods. Index Terms-Multispectral image compression, wavelet transform, classfied inter-channel prediction, selective vetor quantization, subband with lowest resolution.

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Improved characterization method for mobile phone camera and LCD display (모바일 폰 카메라와 LCD의 향상된 특성화 방법)

  • Jang, In-Su;Son, Chang-Hwan;Lee, Cheol-Hee;Song, Kun-Woen;Ha, Yeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.2
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    • pp.65-73
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    • 2008
  • The characterization process for the accurate color reproduction in mobile phone with camera and LCD is popular. The camera and LCD characterization, gamut mapping process is necessary to map the camera's input color stimulus, CIEXYZ value, into the LCD's output color stimulus. Each characterization is the process estimating the relation between input and output signals. In case of LCD, because of output device, the output color stimulus for the arbitrary input signal can be measured by spectro-radiometer However, in the camera, as the input device, the characterization is an inaccurate and needs the manual works in the process obtaining the output signal because the input signal can not be generated. Moreover, after gamut mapping process, the noise is increased because the optimized gamma tone curve of camera for the noise is distorted by the characterization. Thus, this paper proposed the system of obtaining the output signal of camera and the method of gamma correction for the noise. The camera's output signal is obtained by RGB values of patches from captured the color chart image. However, besides the illumination, the error for the location of the chart in the viewfinder is generated when many camera modules are captured the chart. The method of correcting the position to correct the error from manual works. The position of camera is estimated by captured image. This process and moving of camera is accomplished repeatedly, and the optimized position can be obtained. Moreover, the lightness curve of camera output is corrected partly to reduce the noise from the characterization process.

A Development of System for Efficient Quantitative Risk Assessment on Natural Gas Supply Facilities (천연가스 공급시설에 대한 효율적 정량적 위험성 평가를 위한 시스템 구축과 적용)

  • Yoon, Ik-Keun;Oh, Shin-Kyu;Seo, Jae-Min;Lim, Dong-Yeon;Yoon, En-Sup
    • Journal of the Korean Institute of Gas
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    • v.16 no.1
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    • pp.39-45
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    • 2012
  • While the natural gas supply industry has continuously been growing, its potential hazard has also risen since the natural gas facilities essentially require installations that carry highly flammable and pressurized gas close to the populated areas, posing a serious consequence of significant property damage as well as human casualties in the event of accident. Therefore Quantitative Risk Assessment (QAR) has been recognized as a appropriate method to reduce the risk as far as possible, considering the reality of unachievable zero-risk. However, it is hard to perform effective QRA on hundreds of gas facilities because of insufficient number of expert and long-term analysis. In this paper, we suggest a conceptual QRA system framework to support more efficient risk analysis in gas supply facilities. In this system, the experts make questionnaires and internal calculation formula needed in accident frequency/consequence analysis of the facility through pre-analysis on the point of analysis, called incident point, and general users locate the point on the map and input the value required by the questionnaire to obtain the risk. Ultimately, this is suggested based on the idea that the specialization is available in QRA analysis process and the validity of the system is verified through actual system construction and application.

A Study on Forest Inventory Method Using Aerial Photographs (항공사진(航空寫眞)을 이용(利用)한 산림조사(山林調査) 방법(方法)에 관한 연구(硏究))

  • Lee, Chun Yong
    • Journal of Korean Society of Forest Science
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    • v.60 no.1
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    • pp.10-16
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    • 1983
  • This survey was carried out in Schneegattern Forest District which is located 40 km northeast of Salzburg, Austria. The purpose of interpretation with two sampling methods, stratified sampling and unstratified sampling, on B & W infrared photos, with a scale of 1:10,000 was to know coniferous stand volumn and to reduce the cost, Forest stands were classified into 4 groups; those were non-forest, young stands, beech, coniferous stands. Coniferous and beech stands were devided into age classes I (41-80 years), II (above 81 years). After this delineation sample points were designated on the orthophoto map whose data were transferred from the aerial photos. The volumn data were calculated from DBH using relascope in the field and the results were as follows. 1) Coniferous stand volumn per hactare was ($470{\pm}31.9m^3$ 2) The diameter distribution of $C_1$ was binomial, but $C_2$ showed normal distribution. 3) The stratified sampling method was better than unstratified sampling method.

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A Study of GIS-based Estimation of Pollutant Loads in Accordance with Spatial Landuse Variation - Focussing on Wangsook Watershed - (토지이용의 공간적 다양성에 따른 GIS 기반 오염부하 산정에 관한 연구 - 왕숙천 유역을 중심으로 -)

  • Kim, Kyoung-Soon;Kim, Kye-Hyun;Kwon, Oh-Jun
    • Journal of Environmental Impact Assessment
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    • v.14 no.5
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    • pp.305-315
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    • 2005
  • The scheme to classify pollution sources in Korean TMDL planning has been pointed out too much complex to implement practically because of requiring a wide range of items to be collected from a field. Within a deficient situation to collect field data, the mathematical scheme that focuses only on counting an uniform area ratio of the different land uses to estimate of pollutant loads from individual sub-catchments has been used without taking into account of the spatial characteristics of major land uses as well as the locations of pollution sources in each sub-catchment. It would cause to significant level of errors to estimate the pollution loads. Therefore, this study proposes a renovated scheme that can be adopted more easily to classify pollution sources in the watershed and reduce the estimation errors in the spatial distribution of pollution sources by introducing a spatial analysis based on digital land cover maps. In order to estimate a unit area to calculate the uniform pollution load, the pollution response unit area that is locating spatially at the same place and having same land use is identified through the application of GIS overlay technique. Unlikely existing conventional method to calculate the pollution load based on equal distribution of pollutants for each administrative boundary, it is assumed that the pollution load from household and livestock sources are generated and washed off from only residential areas. While, pollution from business population comes from commercial area and industrial load from wastewater discharge facilities are from industrial areas. From comparison of the calculated results from the existing the method and the proposed one, it is found that although the estimation of pollution load from sub-catchment in the case of the existing conventional method application results in negligible difference in total pollution amounts from the whole area of Wangsook watershed as a study area, significant difference of pollution load among sub-catchment in which pollution response unit areas are diverse, however, appears in the case of the application of the renovated scheme.

Evaluation for Applying Low-Cost Mobile Laser System to Earth Volume Calculation at Construction Site (건설현장에서의 토공량산출을 위한 저가형 모바일 레이저시스템의 적용성 평가)

  • Kim, In Seop
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.30 no.6_1
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    • pp.539-547
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    • 2012
  • Volume survey for earthwork is conducted periodically at every month at large scaled construction sites for request payment for the construction. Currently, the earthwork volume is calculated on the overlapped drawing for two cross sections which were created by new and previous surveying data observed by GPS and TS. However the survey is required lots of time and expenses as it is a pin-point surveying method thus surveyors intend to get data only for the heavy undulated topographic features chosen by himself to save time and expenses. Consequently, it causes poor results due to low dense measurement as well as it's not matched with the results by another surveyors. As a result, the conflicts related in earthwork volume calculation often arises among the owner, contractors and sub contractors. In this study, we developed a method to get surveying data for fast and accurate volume calculation using 3D Mobile Laser System and conducted an application test. Also we carried out experiments for topographic survey using MLS to judge for the application additionally. The results showed that we could reduce a time for cross section survey from 48 hours to 2 hours and collected high dense data which have 0.2m interval instead of 3m interval compare with existing method. Also we could make a map which has high accuracy within 10cm in horizontal through topographic survey using MLS.

Prediction of Lahar Flow Inundation Areas Using LAHARZ_py Program: Application for the Mt. Baekdu Volcano (LAHARZ_py 프로그램을 이용한 라하르 범람지역의 예측: 백두산 화산에 적용)

  • Yun, Sung-Hyo;Chang, Cheolwoo
    • Economic and Environmental Geology
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    • v.50 no.4
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    • pp.277-286
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    • 2017
  • Mt. Baekdu which located the border of North Korea and China, is known as a potentially active volcano in a typical mountainous terrain. A lahar on the volcanic area is one of the important hazard that can cause the loss of life and property damage. In order to comprehensively address the impact of lahar hazard at Mt. Baekdu, we simulated lahar inundation area using Laharz_py. We assumed 750 m of additional elevation for DEM to draw proximal hazard zone boundary (PHZB) of Mt. Baekdu that H/L ratio are selected 0.10. And lahar volumes for simulation were estimated to $1{\times}10^6$, $5{\times}10^6$, $1{\times}10^7$, $5{\times}10^7$, $1{\times}10^8$, $5{\times}10^8$, $1{\times}10^9m^3$, respectively. In the results, 15 streams are located near a proximal hazard zone boundary, Amnok (Yalu) river (south), Toudaosonghua river, Jinjiang river and Huapi river (west-southwest), Songjiang river, Xiaosha river, Caozi river and Sandaosongjian river (west-northwest), Toudaobai river, Erdaobai river and Sandabai river (north), Wudaobai river-1, -2, -3 (northeast) and Duman (Tumen) river (east). The results of this study can be used as basic data to make a hazard map for reduce the damage that can be caused by volcanic hazards occurred on Mt. Baekdu.

A Utility-Based Hybrid Error Recovery Scheme for Multimedia Transmission over 3G Cellular Broadcast Networks (3G 방송망에서의 효율적인 멀티미디어 전송을 위한 유틸리티 기반 하이브라드 에러 복구기법)

  • Kang Kyung-Tae;Cho Yong-Jin;Cho Yong-Woo;Cho Jin-Sung;Shin Heon-Shik
    • Journal of KIISE:Information Networking
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    • v.33 no.4
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    • pp.333-342
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    • 2006
  • The cdma2000 lxEV - DO mobile communication system provides broadcast and multicast services (BCMCS) to meet an increasing demand from multimedia data services. The servicing of video streams over a BCMCS network must, however, face a challenge from the unreliable and error-prone nature of the radio channel. The BCMCS network uses Reed-Solomon coding integrated with the MAC protocol for error recovery. We analyze this coding technique and show that it is not effective in the case of slowly moving mobiles. To improve the playback quality of an MPEG-4 FGS video stream, we propose the Hybrid error recovery scheme, which combines Reed-Solomon with ARQ, using slots which are saved by reducing the Reed-Solomon coding overhead. The target packets to be retransmitted are prioritized by a utility function to reduce the packet error rate in the application layer within a fixed retransmission budget. This is achieved by considering of the map of the error control block at each mobile node. The proposed Hybrid error recovery scheme also uses the characteristics of MPEG-4 FGS (fine granularity scalability) to improve the video quality even when conditions are adverse: slow-moving nodes and a high error rate in the physical channel.

The Study of Aerial Triangulation Using GPS (GPS를 이용한 사진기준점 측랑에 관한 연구)

  • 이재원;문두열;김정희;김진수
    • Spatial Information Research
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    • v.12 no.2
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    • pp.181-191
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    • 2004
  • Nowadays, GPS-photogrammetry can be applied to the basemap production, a land register and NGIS. And from now on, as the increase of GPS receiver rate, the study on the interpolation methods considering the exact movement of an aircraft at photoflight and the study on the supplement of GPS defect by INS are required continuously. GPS-Photogrammetry, which are based on the direct measurement of the projection centers and attitude at the moment of camera exposure time through loading the GPS receiver in aircraft. This photogrammetric methods can of for us to acquire the exterior orientation parameters with only minimum ground control points, even the ground control process could be completely skipped. Consequently, we can drastically reduce the time and cost far the mapping process. In this thesis, two test flights were conducted in area to evaluate the performance of accuracy and efficiency through the analysis of results between the two photogrammetric methods, that is, traditional photograrammetry, GPS-Photogrammetry. Test results shows that a large variety of advantages of GPS-Photogrammetry against traditional photogrammetry is to be verified. Especially, the number of ground control points for the exterior orientation could be saved more than 70~80%, and the cost far map production 30~50%, respectively. In addition, it was convinced that the large reduction of control points has not any effect on the block accuracy.

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Cascade CNN with CPU-FPGA Architecture for Real-time Face Detection (실시간 얼굴 검출을 위한 Cascade CNN의 CPU-FPGA 구조 연구)

  • Nam, Kwang-Min;Jeong, Yong-Jin
    • Journal of IKEEE
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    • v.21 no.4
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    • pp.388-396
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    • 2017
  • Since there are many variables such as various poses, illuminations and occlusions in a face detection problem, a high performance detection system is required. Although CNN is excellent in image classification, CNN operatioin requires high-performance hardware resources. But low cost low power environments are essential for small and mobile systems. So in this paper, the CPU-FPGA integrated system is designed based on 3-stage cascade CNN architecture using small size FPGA. Adaptive Region of Interest (ROI) is applied to reduce the number of CNN operations using face information of the previous frame. We use a Field Programmable Gate Array(FPGA) to accelerate the CNN computations. The accelerator reads multiple featuremap at once on the FPGA and performs a Multiply-Accumulate (MAC) operation in parallel for convolution operation. The system is implemented on Altera Cyclone V FPGA in which ARM Cortex A-9 and on-chip SRAM are embedded. The system runs at 30FPS with HD resolution input images. The CPU-FPGA integrated system showed 8.5 times of the power efficiency compared to systems using CPU only.