• Title/Summary/Keyword: Map reduce

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A Study on the Architectural Design Utility of Object-based CAD System (객체기반 CAD 시스템의 건축설계적 효용에 관한 연구)

  • Yoo, Chang-Geun
    • Journal of The Korean Digital Architecture Interior Association
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    • v.2 no.1
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    • pp.9-15
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    • 2002
  • As architectural forms tend to be large-scaled, high-storied and complicated, use of computer for processing design information has been generalized. However, CAD use in the process of developing architectural design has been neglected greatly in the educational field of architectural field due to the surging of recognition that it may limit the essential property of architectural design. It may be resulted from the limitation of CAD system, that is, it is because of tardy speed of application development for the related areas with the lack of simplicity and clarity of flexibility to be secured on the drawing and user interface. Recent CAD systems, however, overcome such a limitation, convert into object-based design from entity-based drawing, drafting and modeling for implementing design concept of architects and it connects with internet linked to superspeed information communication network and changes process and stream of architectural design. Therefore, this study deals with utility of object based CAD system with products of Autodesk Co. and consequently obtain the following conclusions. First, it expands architect's design areas by supporting cooperative design system based on model-based architectural design and internet. Second, it reduces consumption of personal and material resources and time in the process of drawing production for improving architectural design works. Third, it can reduce the frequent design changes by improving understanding of architectural space with visualization of immediate 3D information, escaping from traditional methods to deliver design information to building owner through 2D drawing or model and perspective drawing requiring much cost and time. Fourth, it keeps exactness without omission or duplication of design information and generate and renew information of all related drawings on a drawing. Fifth, it is possible to change difficult and boring architectural design work into a pleasure owing to immediate modeling and drawing of design idea. In addition, digital drawing generated by using object-based CAD system can playa role of establishing Urban Information System to be used for protecting from building in disaster and urban disasters in connection with GIS numerical map and be used for reference of all kinds of information required fro post-management of buildings. However, what is more important is that surplus time from introduction of object-based CAD system should be used for consideration to be recognized as a good space and building built as a product of this project for comfort to urban people.

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An Effective Method for Dimensionality Reduction in High-Dimensional Space (고차원 공간에서 효과적인 차원 축소 기법)

  • Jeong Seung-Do;Kim Sang-Wook;Choi Byung-Uk
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.43 no.4 s.310
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    • pp.88-102
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    • 2006
  • In multimedia information retrieval, multimedia data are represented as vectors in high dimensional space. To search these vectors effectively, a variety of indexing methods have been proposed. However, the performance of these indexing methods degrades dramatically with increasing dimensionality, which is known as the dimensionality curse. To resolve the dimensionality curse, dimensionality reduction methods have been proposed. They map feature vectors in high dimensional space into the ones in low dimensional space before indexing the data. This paper proposes a method for dimensionality reduction based on a function approximating the Euclidean distance, which makes use of the norm and angle components of a vector. First, we identify the causes of the errors in angle estimation for approximating the Euclidean distance, and discuss basic directions to reduce those errors. Then, we propose a novel method for dimensionality reduction that composes a set of subvectors from a feature vector and maintains only the norm and the estimated angle for every subvector. The selection of a good reference vector is important for accurate estimation of the angle component. We present criteria for being a good reference vector, and propose a method that chooses a good reference vector by using Levenberg-Marquardt algorithm. Also, we define a novel distance function, and formally prove that the distance function lower-bounds the Euclidean distance. This implies that our approach does not incur any false dismissals in reducing the dimensionality effectively. Finally, we verify the superiority of the proposed method via performance evaluation with extensive experiments.

Characteristics of the soil loss and soil salinity of upland soil in saemangeum reclaimed land in western South Korea

  • Kim, Young Joo;Lee, Su Hwan;Ryu, Jin Hee;Oh, Yang Yeol;Lee, Jeong Tae
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.316-316
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    • 2017
  • The objective of this study is to estimate quantitatively soil salinity and soil loss at upland soils in agriculture land region in Saemangeum reclaimed land on the south Korea coasts. Soil loss and soil salinity are the most critical problem at reclaimed tidal saline soil in Korea. The several thematic maps of research area such as land cover map, topographic and soil maps, together with tabular precipitation data used for soil erosion and soil salinity calculation. Meteorological data were measured directly as air temperature, wind speed, solar radiation, and precipitation. The experiment was conducted 2% sloped lysimeter ($5.0m{\times}20.0m$) with 14 treatments and it were separated by low salinity division (LSD) and high salinity division (HSD) install. The cation content in ground water increased during time course, but in the case of land surface water the content was variable, and $K^+$ was lower than that of $Na^+$ and $Mg^{2+}$. At the LSD under rainproof condition, the salinity was directly proportional to soil water content, but at the HSD the tendency was no reversed. In condition of rainproof, the amount of soil salinity was higher at the HSD than at the LSD. Positive correlation was obtained between the soil water content and available phosphorous content at the rainfall division, but there was no significance at the surface soil of the rainproof division. Sodium adsorption ratio and anion contents in soil were repressed in the order of vinyl-mulching > non-mulching > bare field. According to the result of analyzing soil loss, soil loss occurred in a vinyl-mulching, a non-mulching and a bare field in size order, and also approximately 11.2 ton/ha soil loss happened on the reclaimed land area. The average soil loss amount by the unit area takes place in a non-mulching and bare field a lot. Our results indicate that soluble salt control and soil erosion are critical at reclaimed tidal saline soil and the results can provide some useful information for deciding management plans to reduce soil loss and salt damage for stable crop production and diverse utilization or cultivation could be one of the management options to alleviate salt damage at reclaimed tidal saline soil in Korea.

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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.