• Title/Summary/Keyword: Scaling Coefficient

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Modelling of Aerosol Vertical Distribution during a Spring Season at Gwangju, Korea

  • Shin, Sung-Kyun;Lee, Kwon-Ho
    • Asian Journal of Atmospheric Environment
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    • v.10 no.1
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    • pp.13-21
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    • 2016
  • The vertical distributions of aerosol extinction coefficient were estimated using the scaling height retrieved at Gwangju, Korea ($35.23^{\circ}N$, $126.84^{\circ}E$) during a spring season (March to May) of 2009. The aerosol scaling heights were calculated on a basis of the aerosol optical depth (AOD) and the surface visibilities. During the observation period, the scaling heights varied between 3.55 km and 0.39 km. The retrieved vertical profiles of extinction coefficient from these scaling heights were compared with extinction profile derived from the Light Detection and Ranging (LIDAR) observation. The retrieve vertical profiles of aerosol extinction coefficient were categorized into three classes according to the values of AODs and the surface visibilities: (Case I) the AODs and the surface visibilities are measured as both high, (Case II) the AODs and the surface visibilities are both lower, and (Others) the others. The averaged scaling heights for the three cases were $3.09{\pm}0.46km$, $0.82{\pm}0.27km$, and $1.46{\pm}0.57km$, respectively. For Case I, differences between the vertical profile retrieved from the scaling height and the LIDAR observation was highest. Because aerosols in Case I are considered as dust-dominant, uplifted dust above planetary boundary layer (PBL) was influenced this discrepancy. However, for the Case II and other cases, the modelled vertical aerosol extinction profiles from the scaling heights are in good agreement with the results from the LIDAR observation. Although limitation in the current modelling of vertical structure of aerosols exists for aerosol layers above PBL, the results are promising to assess aerosol profile without high-cost instruments.

Fractal Scaling of Permeability in Unsaturated Fractured Tuff: Wavelet-Based Approach

  • Hyun, Yunjung
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.140-143
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    • 2003
  • Air permeabilities in unsaturated fractured tuff at the Apache Leap Research Site (ALRS) near Superior, Arizona, exhibit a self-affine behavior, thus renders a field random fractal. Based up fractal scaling, the observed scale effect has been interpreted [Hyun et al., 2002]. Recently, Frantziskonis and Hansen [2000] presented that fractal scaling can be represented based on wavelets. This study deals with the way of using wavelets for fractal scaling. A numerical study is presented to examine the applicability of wavelet-based approach to determining upscaled air permeability values on various data supports at the site. To characterize the scaling property of self-affine fields generated based upon wavelets, Hurst coefficient, H. was inferred by applying the average wavelet coefficient (AWC) method. The result yielded H = 0.24, which is very close to the result of geostatistical analysis using a power variogram (H = 0.22). The study concludes that wavelet-based scaling is a useful way of determining parameter values on different data supports, which is an essential task for modeling of subsurface flow and mass transport in a numeric grid with different resolutions (grid size).

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Study on Scaling Analysis and Design Methodology of Passive Injection Test Facility (피동 주입 시험 장치의 척도 해석 및 설계 방법론 연구)

  • Bae, Hwang;Lee, Minkyu;Ryu, Sung-Uk;Shin, Soo Jai;Kim, Young-In;Yi, Sung-Jae;Park, Hyun-Sik
    • The KSFM Journal of Fluid Machinery
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    • v.19 no.5
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    • pp.50-60
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    • 2016
  • A design methodology of the modeled test facility to conserve an injection performance of a passive safety injection system is proposed. This safety injection system is composed of a core makeup tank and a safety injection tank. Individual tanks are connected with pressure balance line on the top side and injection line on the bottom side. It is important to conserve the scaled initial injection flow rate and total injection time since this system can be operated by small gravity head without any active pumps. Differential pressure distribution of the injection line induced by the gravity head is determined by the vertical length and elevation of each tank. However, the total injection time is adjustable by the flow resistance coefficient of the injection line. The scaling methodology for the tank and flow resistance coefficient is suggested. A key point of this test facility design is a scaling analysis for the flow resistance coefficient. The scaling analysis proposed on this paper is based on the volume scaling law with the same vertical length to the prototype and can be extended to a model with a reduced vertical length. A set of passive injection test were performed for the tanks with the same volume and the different length. The test results on the initial flow rate and total injection time showed the almost same injection characteristics and they were in good agreement with the design values.

Recognition about national health insurance of dental scaling in industry accident injury patients (스케일링 건강보험 급여화에 대한 산재환자의 인식도)

  • Lee, Hea Shoon;Lee, Kyung Hee
    • Journal of Korean society of Dental Hygiene
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    • v.13 no.4
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    • pp.561-568
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    • 2013
  • Objectives : The purpose of this study is to examine the recognition and needs on the national health insurance coverage of scaling in industry accident injury patients. National health insurance coverage of dental scaling will start in September, 2013. Methods : Subjects were 649 industrial injury patients and they completed self-reported questionnaire. Data were analysed using SPSS version 20.0 for percentage, chi-square test, t-test, ANOVA, post-hoc Scheffe test, and Pearson's correlation coefficient. Results : Recognition on national health insurance coverage of dental scaling was not fully known to industrial injury patients (24.5%). Highly educated and high income workers seemed to recognize national health insurance coverage of dental scaling (p<.001). Recognition for national health insurance coverage of dental scaling revealed a significance (r=.576, p<.001). Most of the industrial injury workers thought that 50,000 to 100,000 Korean Won of dental scaling fee is reasonable. The coverage of dental scaling should be more than twice over 20 years old. Conclusions : It is necessary to encourage the patients to take regular dental scaling checkup and make them know the health insurance coverage of scaling. The preventive oral health care may improve oral health care and quality of life.

Robust Blind Watermarking using DCT Texture Block Coefficient (DCT 질감 블록 계수를 이용한 강인한 블라인드 워터마킹)

  • Shin, Yong-Dal;Park, Kyung-Nam
    • Journal of Korea Society of Industrial Information Systems
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    • v.13 no.4
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    • pp.108-114
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    • 2008
  • In this paper, we proposed robust blind watermarking algorithm using texture block coefficient based on discrete cosine transform(DCT). The proposed method embedded all of watermark signals into DC component of $8\times8$ block DCT in order to robust various external attack The texture block coefficient was composed absolute value of DCT coefficients. Experiment showed that the proposed method better than conventional methods in the invisibility and various attack such as dithering, cropping, and scaling.

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Three-dimensional Display of Microscopic Specimen using Integral Imaging Microscope and Display (집적 영상 현미경과 집적 영상 디스플레이를 이용한 미세시료의 3차원 영상 재생)

  • Lim, Young-Tae;Park, Jae-Hyeung;Kwon, Ki-Chul;Kim, Nam
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.11B
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    • pp.1311-1319
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    • 2009
  • Microscopic specimen was captured by an integral imaging microscope and displayed as a three-dimensional image by an integral imaging display system. We applied the generalized relationship between pickup and display using two different lens arrays to our integral imaging microscope and display system. In order to display three-dimensional microscopic image, scaling of the captured elemental images is required. We analyzed the effect of the scaling coefficient in terms of the distortion of the displayed three-dimensional image and the loss of the captured elemental images. In our experiment, microscopic specimen is picked up by an integral imaging microscope having $125{\mu}m$ elemental lens pitch and displayed as three-dimensional image by an integral imaging display system having 1mm elemental lens pitch. The scaling coefficient was chosen to minimize the elemental image loss.

A Performance Variation by Scaling Factor in NM-MMA Adaptive Equalization Algorithm (NM-MMA 적응 등화 알고리즘에서 Scaling Factor에 의한 성능 변화)

  • Lim, Seung-Gag
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.18 no.2
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    • pp.105-110
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    • 2018
  • This paper compare the adaptive equalization performance of NM-MMA (Novel Mixed-MMA) algorithm which using the mixed const function by scaling factor values. The mixed cost function of NM-MMA composed of the appropriate weighted addition of gradient vector in the MMA and SE-MMA cost function, and updating the tap coefficient based on these function, it is possible to improve the convergence speed and MSE value of current algorithm. The computer simulation was performed in the same channel, step size, SNR environment by changing the scaling factor, and its performance were compared appling the equalizer output constellation, residual isi, MD, MSE, SER. As a result of computer simulation, the residual values of performance index were reduced in case of the scaling factor of MMA cost function was greater than the scaling factor of SE-MMA. and the convergence speed was improved in case of the scaling factor of SE-MMA was greater than the MMA.

A new Robust Wavelet Shift Keying System Using Scaling and Wavelet Functions (스케일링 함수와 웨이브릿을 이용한 잡음에 강인한 새로운 웨이브릿 편이 변조 시스템)

  • Jeong, Tae-Il
    • Journal of the Institute of Convergence Signal Processing
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    • v.9 no.2
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    • pp.98-103
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    • 2008
  • There are the frequency shift keying(FSK), phase shift keying(PSK) and amplitude shift keying(ASK) in the conventional digital communications method. In this paper, We proposed a new robust wavelet shift keying system using scaling and wavelet function in the digital communication. Wavelet Transform consist of a low frequency and high frequency coefficient. When the input signal is one, if it finds the impulse response, the signal is separated from the scaling and wavelet function. The binary data is encoded by modulator which assigned the scaling function to 1(one), and wavelet to zero(0). It was demonstrated by experiment that the proposed algorithm can be a robust noise.

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A Study on the Diagnostic Technology for Fouling Occurred in Heat Exchanger (열교환설비에서의 파울링 진단기술에 관한 연구)

  • Chung Kyung-Yul;Rhyu Keel-Soo;Lee Hoo-Rach
    • Journal of Advanced Marine Engineering and Technology
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    • v.29 no.5
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    • pp.502-508
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    • 2005
  • Fouling causes serious maintenance problems on heat exchanger tubes and process facilities. To avoid such fouling problems, numerous efforts have been tried. e.g., diagnosis of fouling, reducing and eliminating the fouling. etc.. The objective of the present study is to develop an innovative diagnostic system of fouling, which can detect the scaling attached to the wall non-homogeneously. The performance of the diagnostic system has been evaluated with a scaling simulator that generates scaling on tested tube wall. The measured values with the diagnostic system were compared with the amounts of the scaling generated by the simulator. In addition to, we showed the data that have been executed in field test for reliability verification.

A Study on Performance Analysis for Error Probability in SWSK Systems

  • Jeong, Tae-Il;Moon, Kwang-Seok;Kim, Jong-Nam
    • Journal of information and communication convergence engineering
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    • v.9 no.5
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    • pp.556-561
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    • 2011
  • This paper presents a new method for shift keying using the combination of scaling function and wavelet named scaling wavelet shift keying (SWSK). An algorithm for SWSK modulation is carried out where the scaling function and the wavelet are encoded to 1 and 0 in accordance with the binary input, respectively. Signal energy, correlation coefficient and error probability of SWSK are derived from error probability of frequency shift keying(FSK). The performance is analyzed in terms of error probability and it is simulated in accordance with the kind of the wavelet. Based on the results, we can conclude that the proposed scheme is superior to the performance of the conventional schemes.