• Title/Summary/Keyword: white paper on environment

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A Study on the Denoising Method by Multi-threshold for Underwater Transient Noise Measurement (수중 천이소음측정을 위한 다중 임계치 잡음제거기법 연구)

  • 최재용;도경철
    • The Journal of the Acoustical Society of Korea
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    • v.21 no.6
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    • pp.576-584
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    • 2002
  • This paper proposes a new denosing method using wavelet packet, to reject unknown external noise and white gaussian ambient noise for measuring the transient noise which is one of the important elements for ship classification. The previous denosing method applied the same wavelet threshold at each node of multi-single sensors for rejecting white noise is not adequate in the underwater environment existing lots of external noises. The proposed algorithm of this paper applies a modified soft-threshold to each node according to the discriminated threshold so as to reject unknown external noise and white gaussian ambient noise. It is verified by numerical simulation that the SNR is increased more than 25㏈. And the simulation results are confirmed through sea-trial using multi-single sensors.

STATISTICAL ANALYSIS OF AN AUTOCALIBRATION METHOD FOR QUADRATURE RECEIVERS

  • Soonman Kwon;Kim, Seogjoo;Lee, Jongmoo
    • Proceedings of the IEEK Conference
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    • 2000.07a
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    • pp.517-520
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    • 2000
  • This paper deals with the statistical analysis of an autocalibration procedure for the gain and phase imbalances between the in-phase (I) and quadrature (Q) components in quadrature receivers. In real implementation, the imbalances of the gain and phase exist and degrade the performance of the receiver. In this paper we investigate the statistical characteristic of the estimates in an on-line imbalance estimation method for the receiver under the assumption of an additive white Gaussian noise environment.

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Multi images preprocess method for License Plate Recognition on poor environment (열악한 환경에서 번호판 인식을 위한 다중 이미지 전처리 방법)

  • Kim, Hyun-Woo;Kim, Y.M.
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.477-480
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    • 2005
  • In this paper, we propose a preprocess method to needs for Car License Plate Recognition on poor environment. This preprocess method use multi images to get low value to compare images value. Last method was Opening operation that Using Edge pixel to add and subtraction. The Result was removed White pixel and very mini feather. But This method needs many process times and License Plate Recognition is low quality problem. Another method is median filter and conversion. This paper key idea that rain & snow is high value. So This paper propose get low value to compare image value.

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A Study on the Straight Path Prediction Technology of White LED Marker-based AGV in Indoor Environment (실내 환경에서 White LED 마커 기반 무인 운반차의 직진경로 예측 기술 연구)

  • Woo, Deok gun;vinayagam, Mariappan;Kim, Young min;Cha, Jae sang
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.17 no.5
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    • pp.48-54
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    • 2018
  • With the 4th industry era, smart factories are emerging. In the era of multi-product small scale production, unmanned transportation vehicles are rapidly increasing in utilization of unmanned transportation vehicles that carry and arrange goods in the work space. The conventional unmanned vehicle detected its position by using the guided line method and the position based method for indoor location recognition and movement. This method has disadvantages of initial high cost and maintenance / maintenance. In this paper, to solve the disadvantages, the method of predicting the direct path of the unmanned vehicle through the Kalman filter is verified using the white LED marker of the warehouse and the position data and the image data of the white LED marker recognition image. Through this, the reliability of the linear movement which occupies the most part in the lattice structure is secured. It is also expected that the reliance on additional position sensors will also be reduced.

Behaviour of self compacting repair mortars based on natural pozzolana in hot climate

  • Benyahia, A.;Ghrici, M.
    • Advances in concrete construction
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    • v.6 no.3
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    • pp.285-296
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    • 2018
  • In the present paper, the results of an experimental study of the bond between repair materials and mortar substrate subjected to hot climate is presented. Half-prisms of size $40{\times}40{\times}80mm$, serving as a substrate mortar samples (SUBM) were manufactured in the laboratory and then stored at an ambient temperature for 6 months. Five self compacting mortar mixes (SCMs) incorporating 0%, 10%, 20%, 30%, and 40% of natural pozzolana as white cement replacement were used as repair materials. Repaired composite samples (SCMs/SUBM) were cured at hot climate for different lengths of time (28 and 56-days). During the first week of curing, the composite samples were watered twice a day. The test carried out to assess the bond between SCMs and SUBM was based on three-point bending (3 PB) test. The obtained results have proved that it was feasible to produce compatible repair materals in this curing environment by using up to 30% natural pozzolana as white cement replacement.

Corresponding Color Reproduction on CRT between Illuminated Environment viewing Conditions (관찰환경에 따른 소프트카피의 대응적 색재현)

  • 곽한봉;안성아;서봉우;이영호;안석출
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2001.06a
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    • pp.241-244
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    • 2001
  • A various color device became generalization. Therefore, request about expression of correct color is increased. Device independent color reproduction system acquires and reproduce color of object regardless characteristic of Input/Output device. Human visual system is partially adapted to the CRT monitor's white point and the ambient light. The visual experiments were performed on the effect of the ambient lighting under mixed chromatic adaptation. In this paper, It was found that human visual system is 40% to 60% adapted to CRT monitor's white point light and the rest to ambient light.

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An Effective Method for Selection of WGN Band in Man Made Noise(MMN) Environment (인공 잡음 환경하에서의 효율적인 백색 가우시안 잡음 대역 선정 방법)

  • Shin, Seung-Min;Kim, Young-Soo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.11
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    • pp.1295-1303
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    • 2010
  • In this paper, an effective method has been proposed for selection of white Gaussian noise(WGN) band for radio background noise measurement system under broad band noise environment. MMN which comes from industrial devices and equipment mostly happens in the shape of broad band noise mostly like impulsive noise and this is the main reason for increasing level in the present radio noise measurements. The existing method based on singular value decomposition has weak point that it cannot give good performance for the broad band signal because it uses signal's white property. The proposed method overcomes such a weakness of singular value decomposition based method by using signal's Gaussian property based method in parallel. Moreover, this proposed method hires a modelling based method which uses parameter estimation algorithm like maximum likelihood estimation(MLE) and gives more accurate result than the method using amplitude probability distribution(APD) graph. Experiment results under the natural environment has done to verify feasibility of the proposed method.

Characteristics of Design Elements in Environment-Friendly Fashion -Focus on the Content Analysis of Previous Literature- (친환경패션에 나타난 디자인적 요소의 특성 -선행연구의 내용분석을 중심으로-)

  • Ha, Seung-Yeon;Park, Jae-Ok
    • Journal of the Korean Society of Clothing and Textiles
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    • v.33 no.8
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    • pp.1280-1292
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    • 2009
  • In the current fashion design, the 'environmental friendliness' affects the practically and conceptuality in all industry and culture sectors. This study seeks to examine specific design elements as the content of design factors in environment oriented fashion. The subjects of this paper are studied through scholarly journals that are confined to those from 1990 (when naturalism and ecology trends started to be in fashion) to February 2009. This study used 'Naturalism', 'Green', 'Environment-friendly', 'Eco', 'Sustainable', 'Well-being' and 'Lohas' as key words for the literature search. The analysis is performed through a content analysis and the unit of analysis is based upon the adjectives, nouns, and phrases related to the content of the design elements such as line, color, and textiles. In the results, more expression is natural, minimal, transformable, and sportive style in line, YR, white, soft, pale, and dull tone in color. The prominent textiles and texture were natural fabrics, environment-friendly fabrics, recycled fabrics, natural dyeing, functional finishes, rustic surfaces, flexibility, and extensibility. The results of this paper will help in future fashion design product development for environment-friendly fashion brands.

Handsheet Property Changes by Internal Addition of Surface Strength Agent (표면강도 향상제 내첨에 따른 수초지 특성 변화)

  • Lim, Jong-Hyck;Jung, Chul-Hun;Chae, Hee-Jae;Park, Chang-Soon;Park, Jong-Moon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.42 no.2
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    • pp.41-45
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    • 2010
  • This study was performed to evaluate the effect of paper property changes by internal addition of surface strength agent on printability. Advances in printing technique has required the development of paper qualities in many aspects. Basically paper structure is composed of hydrogen bonds which induce many problems in high speed printing machine because of weak bonding strength. One of the important printing problems is surface picking when mechanical pulp or recycled pulp are used. It was caused by the ink-stained blanket in printing process because accumulations of pollutant in white water and other elements which are bonded weakly or do not have hydrogen bonds. Debris at paper surface adheres to blanket which deteriorates printing efficiency and causes various problems. To complement these problems, Pennocel 5137 of polysaccharide structure was used as an agent to improve paper's surface property, strength and printability. Paper surface picking was analyzed by RI-1 test. As the dosage amount increased tensile strength, fiber bonding strength and ZDT strength were improved. Further more formation, smoothness and surface picking resistance were improved. It was confirmed that when adding polysaccharide structure polymers to improve surface strength such as surface picking resistance, it was also possible to improve tensile strength, fiber bonding strength, formation and smoothness.

An Implementation of the Spam Mail Prevention System Using Reply Message with Secrete Words (비밀단어의 회신을 이용한 스팸메일 차단 시스템의 구현)

  • Ko Joo Young;Shim Jae Chang;Kim Hyun Ki
    • Journal of Korea Multimedia Society
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    • v.8 no.1
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    • pp.111-118
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    • 2005
  • This paper describes an implementation of the spam mail prevention system using reply message with secrete words. When user receives a new e-mail, the e-mail address is compared with the white e-mail addresses in database by the system. If user receives a new e-mail which does not exist in a white e-mail addresses database, a reply e-mail attached with secrete words is delivered automatically. And the system is compared with the white domains first for intranet environment. It speeds up processing time. proposed algorithm is required a small database and faster than the black e-mail addresses comparison. This system is implemented using procmail, PHP and IMAP on Linux and the user can manage the databases on the web.

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