• Title/Summary/Keyword: Sampling method

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A Study on Human Body Tracking Method for Application of Smartphones (스마트폰 적용을 위한 휴먼 바디 추적 방법에 대한 연구)

  • Kim, Beom-yeong;Choi, Yu-jin;Jang, Seong-wook;Kim, Yoon-sang
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.10a
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    • pp.465-469
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    • 2017
  • In this paper we propose a human body tracking method for application of smartphones. The conventional human body tracking method is divided into a sensor-based method and a vision-based method. The sensor-based methods have a weakness in that tracking accuracy is low due to cumulative error of position information. The vision-based method has no cumulative error, but it requires reduction of the computational complexity for application of smartphone. In this paper we use the improved HOG algorithm as a human body tracking method for application of smartphone. The improved HOG algorithm is implemented through downsampling and frame sampling. Gaussian pyramid is applied for downsampling, and uniform sampling is applied for frame sampling. We measured the proposed algorithm on two devices, four resolutions, and four frame sampling intervals. We derive the best detection rate among downsampling and frame sampling parameters that can be applied in realtime.

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Feasibility Study on Sampling Ocean Meteorological Data using Stratified Method (층화추출법에 의한 해양기상환경의 표본추출 타당성 연구)

  • Han, Song-I;Cho, Yong-Jin
    • Journal of Ocean Engineering and Technology
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    • v.28 no.3
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    • pp.254-259
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    • 2014
  • The infrared signature of a ship is largely influenced by the ocean environment of the operating area, which has been known to cause large changes in the signature. As a result, the weather condition has to be clearly set for an analysis of the infrared signatures. It is necessary to analyze meteorological data for all the oceans where the ship is supposed to be operated. This is impossibly costly and time consuming because of the huge size of the data. Therefore, the creation of a standard environmental variable for an infrared signature research is necessary. In this study, we compared and analyzed sampling methods to represent ocean data close to the Korean peninsula. In order to perform this research, we collected ocean meteorological records from KMA (Korea Meteorological Administration), and sampled these in numerous ways considering five variables that are known to affect the infrared signature. Specifically, a simple random sampling method for all the data and 1-D, 2-D, and 3-D stratified sampling methods were compared and analyzed by considering the mean square errors for each method.

Determination of Sample Size and Comparison of Efficiency in Adaptive Cluster Sampling (적응집락추출에서 표본크기 결정과 추정량의 효율 비교)

  • NamKung, Pyong;Won, Hye-Kyoung;Choi, Jae-Hyuk
    • The Korean Journal of Applied Statistics
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    • v.20 no.3
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    • pp.605-618
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    • 2007
  • Adaptive sampling design is the selection procedure which depends on observed values of the variable of interest. It is the method which could be applied to the rare and unapproachable population. Adaptive cluster sampling strategies are more efficient than simple random sampling on equivalent sample size. Adaptive sampling with new estimators through the Rao-blackwell method have lower variance than Horvitz-Thompson (HT) and Hansen-Hurwitz (HH). Also, to determine suitable sample size, it was used expected sample and the method finding appropriate sample size by changing initial sample size were studied.

Evaluation of Ground-Water Sampling Techniques for Analysis of Chlorofluorocarbons (지하수의 CFCs(Chlorofluorocarbons) 조사를 위한 시료 채취 방법의 평가)

  • 고동찬;이대하
    • Journal of Soil and Groundwater Environment
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    • v.8 no.2
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    • pp.1-8
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    • 2003
  • Two types of ground-water sampling techniques for CFCs (chlorofluorocarbons) analysis, the cold-welded copper tube method and flame-sealed borosilicate glass ampule method, were compared and evaluated. CFCs concentrations by the copper tube method showed a poor reproducibility among triplicates whereas those by the glass ampule method showed a good agreement and relative standard deviations of triplicates were less than 5%. The poor reproducibility of the copper tube method appears to be attributed to the incomplete sealing in connection between faucets of wellhead and the sampling apparatus. The copper tube method also showed higher CFCs concentrations than the glass ampule method, which is more pronounced for CFC-11 than for CFC-12. The plastic tubings and rubber gasket of faucets in case of the copper tube method possibly contaminated the samples with CFC-11 and CFC-12. The potential of CFCs contamination for the glass ampule method was eliminated by using stainless steel and Nylon only and by connecting the sampling equipment directly to the main discharge pipe of wellhead. The validity of the glass ampule method were also verified by detecting very low level of CFCs for the ground-water sample which is old enough to have negligible CFCs.

A sampling and estimation method for monitoring poultry red mite (Dermanyssus gallinae) infestation on caged-layer poultry farms

  • Oh, Sang-Ik;Park, Ki-Tae;Jung, Younghun;Do, Yoon Jung;Choe, Changyong;Cho, Ara;Kim, Suhee;Yoo, Jae Gyu
    • Journal of Veterinary Science
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    • v.21 no.3
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    • pp.41.1-41.12
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    • 2020
  • Background: The poultry red mite, Dermanyssus gallinae, is a serious problem in the laying hen industry worldwide. Currently, the foremost control method for D. gallinae is the implementation of integrated pest management, the effective application of which necessitates a precise monitoring method. Objectives: The aim of the study was to propose an accurate monitoring method with a reliable protocol for caged-layer poultry farms, and to suggest an objective classification for assessing D. gallinae infestation on caged-layer poultry farms according to the number of mites collected using the developed monitoring method. Methods: We compared the numbers of mites collected from corrugated cardboard traps, regarding with length of sampling periods, sampling sites on cage, and sampling positions in farm buildings. The study also compared the mean numbers of mites collected by the developed method with the infestation levels using by the conventional monitoring methods in 37 caged-layer farm buildings. Results: The statistical validation provided the suitable monitoring method that the traps were installed for 2 days on feed boxes at 27 sampling points which included three vertical levels across nine equally divided zones of farms. Using this monitoring method, the D. gallinae infestation level can be assessed objectively on caged-layer poultry farms. Moreover, the method is more sensitive than the conventional method in detecting very small populations of mites. Conclusions: This method can be used to identify the initial stages of D. gallinae infestation in the caged-layer poultry farms, and therefore, will contribute to establishment of effective control strategies for this mite.

Performance Evaluation of Synchronization Method for Reducing the Overall Synchronization Time in Digital Radio Mondiale Receivers

  • Kwon, Ki-Won;Kim, Seong-Jun;Hwang, Jun;Paik, Jong-Ho
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.8
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    • pp.1860-1875
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    • 2013
  • In this paper, we present a comparative performance evaluation of the sampling frequency synchronization method that eliminates the initial sampling frequency offset (SFO) to reduce the overall synchronization time in Digital Radio Mondiale (DRM) receivers. To satisfy the advanced synchronization performance requirements of DRM receivers, we introduce the conventional DRM synchronization method (Method 1) and another method (Method 2), which does not perform the initial sampling frequency synchronization in the conventional synchronization method (both methods are mentioned later in this paper). To demonstrate the effectiveness of the performance evaluation, analytical expressions for frame detection are derived and simulations are provided. Based on the simulations and numerical analysis, our result shows that Method 2, with a negligible performance loss, is robust to the effects of the initial sampling frequency synchronization even if SFO is present in the DRM signal. In addition, we verify that the inter-cell differential correlation used between reference cells is robust to the effect of the initial SFO.

Comparison between Head Space Gas Sampling and Purge & Trap Sampling in Water Analysis

  • Nagayanagi, Yutaka;Nakagawa, Katsuhiro;Saito, Yoshihiro;Kim, Poongzag
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.739-744
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    • 1995
  • The two main methods to prepare water samples for analyzing volatile organic compounds(VOC's) were investigated. One is the purge and trap(PT) method and another is the head space(HS) sampling method. Both methods were effective to transfer the low boiling point components from the water sample onto the capillary column. The cryo-focusing at the top of the main capillary column was an effective way to obtain the sharpness of the chromatographic peaks but could be avoided when a semi-wide bore column was used. The recovery from the same amount of the sample was better in PT than in HS but a larger sample volume in HS method could compensate the lower efficiency. Therefore PT is suitable to the analysis of drinking water where the very low concentration must be determined. HS is suitable to waste water analysis because of the easiness of the operation. The repeatability was good and similar in both methods. For the contamination of the former sample, both methods were tough and could be used without any problems. The matrix effect which could change the equilibrium parameters in HS method was find negligible in many components. The actual samples such as tap water and river water were analyzed with both methods concerning 16 components regulated in Korea.

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Physical modeling synthesizing of 25 strings Gayageum using white noise as exciter (화이트 노이즈를 익사이터로 이용하는 25현 가야금의 피지컬 모델링 신디사이징)

  • Bae, June;Kim, Jangyoung;Yang, Yoongi
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.5
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    • pp.740-746
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    • 2018
  • Up until now, attempts to produce computer instruments have been largely focused on two types of sampling methods and physical modeling. Since the sampling method removes much of the harmonics in the sampling process, the effect of exciter that emphasizing the harmonic of the strings are mini. However, the physical modeling method can produce a lot of harmonics, and by emphasizing the harmonics of a particular frequency band among these harmonics, it is possible to produce a sound more like a lively sound. In this paper, we propose a method of using white noise in realizing exciter emphasizing harmonics of pre - specified frequency band in prefectural physical modeling. And comparing the envelope and spectrum of the Gayageum sound, we confirmed that the physical modeling method with the exciter is more suitable for the actual Gayageum sound than the sampling method and the conventional physical modeling method.

Empirical Bayes Estimation on Sampling Inspection by Variables (계량형 샘플링 검사에서의 경험적 베이즈 추정)

  • Shin, Min-Woong;Shin, Key-II
    • Journal of Korean Society for Quality Management
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    • v.23 no.3
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    • pp.45-56
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    • 1995
  • The method of lot by lot quality protection for sampling inspection by variables is widely used in quality control. In case of sampling inspection being done repeatedly, one can use the information from the previous sampling inspection to improve current estimates. This article shows that empirical Bayes estimator is superior to the usual sample mean in repeated sampling inspection by variables.

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Some Perspectives on Variance Estimation in Sampling with Probability Proportional to Size

  • Kim, Sun-Woong
    • Proceedings of the Korean Statistical Society Conference
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    • 2005.05a
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    • pp.233-238
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    • 2005
  • S${\"{a}}$rndal (1996) and Knottnerus (2003) had a critical look at the well known variance estimator of Sen (1953) and Yates and Grundy (1953) in probability proportional to size sampling. In this paper, we point out that although their approaches can avoid the difficulties in variance estimation with respect to the joint probabilities, there exist the disadvantages in practice. Also, we describe a sampling procedure available in statistical software that are useful for the variance estimation.

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