• Title/Summary/Keyword: Sampling location

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Fault Location and Classification of Combined Transmission System: Economical and Accurate Statistic Programming Framework

  • Tavalaei, Jalal;Habibuddin, Mohd Hafiz;Khairuddin, Azhar;Mohd Zin, Abdullah Asuhaimi
    • Journal of Electrical Engineering and Technology
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    • v.12 no.6
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    • pp.2106-2117
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    • 2017
  • An effective statistical feature extraction approach of data sampling of fault in the combined transmission system is presented in this paper. The proposed algorithm leads to high accuracy at minimum cost to predict fault location and fault type classification. This algorithm requires impedance measurement data from one end of the transmission line. Modal decomposition is used to extract positive sequence impedance. Then, the fault signal is decomposed by using discrete wavelet transform. Statistical sampling is used to extract appropriate fault features as benchmark of decomposed signal to train classifier. Support Vector Machine (SVM) is used to illustrate the performance of statistical sampling performance. The overall time of sampling is not exceeding 1 1/4 cycles, taking into account the interval time. The proposed method takes two steps of sampling. The first step takes 3/4 cycle of during-fault and the second step takes 1/4 cycle of post fault impedance. The interval time between the two steps is assumed to be 1/4 cycle. Extensive studies using MATLAB software show accurate fault location estimation and fault type classification of the proposed method. The classifier result is presented and compared with well-established travelling wave methods and the performance of the algorithms are analyzed and discussed.

An Assessment of Air Sampling Location for Stack Monitoring in Nuclear Facility (원자력시설 굴뚝 내 공기시료채취 위치의 적절성 평가)

  • Lee, JungBok;Kim, TaeHyoung;Lee, JongIl;Kim, BongHwan
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.2
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    • pp.173-180
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    • 2017
  • In this study, air sampling locations in the stack of the Advanced Fuel Science Building (AFSB) at the Korea Atomic Energy Research Institute (KAERI) were assessed according to the ANSI/HPS N13.1-1999 specification. The velocity profile, flow angle and $10{\mu}m$ aerosol particle profile at the cross-section as functions of stack height L and stack diameter D (L/D) were assessed according to the sampling location criteria using COMSOL. The criteria for the velocity profile were found to be met at 5 L/D or more for the height, and the criteria for the average flow angle were met at all locations through this assessment. The criteria for the particle profile were met at 5 L/D and 9 L/D. However, the particle profile at the cross-section of each sampling location was found to be non-uniform. In order to establish uniformity of the particle profile, a static mixer and a perimeter ring were modeled, after which the degrees of effectiveness of these components were compared. Modeling using the static mixer indicated that the sampling locations that met the criteria for the particle profile were 5-10 L/D. When modeling using the perimeter ring, the sampling locations that met the criteria for particle profile were 5 L/D and 7-10 L/D. The criteria for the velocity profile and the average flow angle were also met at the sampling locations that met the criteria for the particle profile. The methodologies used in this study can also be applied during assessments of air sampling locations when monitoring stacks at new nuclear facilities as well as existing nuclear facilities.

Application of Bayesian Computational Techniques in Estimation of Posterior Distributional Properties of Lognormal Distribution

  • Begum, Mun-Ni;Ali, M. Masoom
    • Journal of the Korean Data and Information Science Society
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    • v.15 no.1
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    • pp.227-237
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    • 2004
  • In this paper we presented a Bayesian inference approach for estimating the location and scale parameters of the lognormal distribution using iterative Gibbs sampling algorithm. We also presented estimation of location parameter by two non iterative methods, importance sampling and weighted bootstrap assuming scale parameter as known. The estimates by non iterative techniques do not depend on the specification of hyper parameters which is optimal from the Bayesian point of view. The estimates obtained by more sophisticated Gibbs sampler vary slightly with the choices of hyper parameters. The objective of this paper is to illustrate these tools in a simpler setup which may be essential in more complicated situations.

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The Influence of Experiential Marketing and Location on Customer Loyalty

  • SOLIHA, Euis;AQUINIA, Ajeng;HAYUNINGTIAS, Kristina Anindita;RAMADHAN, Kartiko Rizkika
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.3
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    • pp.1327-1338
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    • 2021
  • This study aims to examine how experiential marketing and location influence customer loyalty mediated by customer satisfaction. This study's population was Cafe Excelso Rinjani customers in Semarang, Indonesia. The sampling employed a purposive sampling technique, with the following criteria: customers who visited and enjoyed Cafe Excelso Rinjani and aged more than 17 years. Data analysis used multiple regression analysis, and a single test was utilized to test for mediation. The results revealed that experiential marketing positively and significantly affected customers satisfaction. It showed that the better the experiential marketing was done, the more customer satisfaction would be. Location positively and significantly influenced customer satisfaction. It indicated that the more strategic the location, the more customer satisfaction increased. Meanwhile, experiential marketing had no impact on customer loyalty. Location positively and significantly affected customer loyalty at Cafe Excelso Rinjani Semarang. It denoted that the more strategic the location, the more customer loyalty increased. Besides, customer satisfaction had a positive and significant effect on customer loyalty. It signified that, when customer satisfaction increased, customer loyalty would increase. Finally, customer satisfaction perfectly mediated the influence of experiential marketing on customer loyalty, and customer satisfaction mediated the effect of location on customer loyalty.

Factors Affecting Students' Decision to Select Private Universities in Vietnam

  • LE, Hung Quang
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.4
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    • pp.235-245
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    • 2020
  • The study seeks to identify factors affecting the choice of a university by first-year Business Administration students in Vietnam. Probability sampling is using Stratified sampling of 500 students from five private universities in Ho Chi Minh City surveyed by convenience sampling. This paper employs mixed research methods - measuring Cronbach's Alpha, EFA, Regression and using PATH model - to test the hypotheses of the research model. The results of the study identify five factors: Prestige, Geographical location, Facilities, Attractiveness of the field and Media. All these factors have a positive influence on the standing of the university brand. It means that the higher the Prestige, Geographical location, Facilities, Attractiveness of the field and Media, the higher the university brand. The results indicate that Geographical location is the most influential factor to enhance the private university's brand. Bringing Geographical location is, thus, advisable to enhance a university standing. The brand plays a determining role in students' trust when selecting a university. Media is still the top concern of new students when they choose to study at a university. Media still remains an important consideration for new students when choosing a university. So, this factor should be utilized by universities to enhance their attractiveness.

A Study on the Role of Pivots in Bayesian Statistics

  • Hwang, Hyungtae
    • Communications for Statistical Applications and Methods
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    • v.9 no.1
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    • pp.221-227
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    • 2002
  • The concept of pivot has been widely used in various classical inferences. In this paper, it is proved by use of pivotal quantities that the Bayesian inferences can be arrived at the same results of classical inferences for the location-scale parameters models under the assumption of non-informative prior distributions. Some theorems are proposed in which the posterior distribution and the sampling distribution of a pivotal quantity coincide. The theorems are applied illustratively to some statistical models.

Rapid Measurement of VOC Using an Analysis of Soil-Gas (Soil-Gas의 분석을 이용한 휘발성 유기화합물 오염도 신속측정)

  • 김희경;조성용;황경엽
    • Journal of Korea Soil Environment Society
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    • v.3 no.1
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    • pp.3-9
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    • 1998
  • This paper presents soil-gas surveying technique to delineate an area contaminated with volatile organic compounds, which are common solvents and constituents of gasoline. The sampling method of soil-gas surveying is 1) grab sampling, which actively takes sample using a pump, or 2) passive sampling, which takes sample through diffusion in a trap filled with absorbent. The grab sampling shows the level of contamination at a certain location at a certain time, while the passive sampling shows the change in the contamination at a certain location. The analysis of soil gas can be performed with 1) a small portable detectors such as PID (photoionization detector) or FID (flame-ionization detector) to measure the total hydrocarbon in the soil gas, 2) a gas detector tube, which is filled with indicator reagents and changes its color with concentrations of the gas of interest, or 3) a portable GC (gas chromatograph), which can analyze different compounds simultaneously. The soil-gas surveying technique is a much less expensive method to investigate area contaminated volatile organic compounds and thus can be used as a screening tool to identify an area, which needs to be further investigated.

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Location of Sampling Points in Optical Reflectance Measurements of Chinese Cabbage and Kale Leaves

  • Ngo, Viet-Duc;Kang, Sin-Woo;Ryu, Dong-Ki;Chung, Sun-Ok;Park, Sang-Un;Kim, Sun-Ju;Park, Jong-Tae
    • Journal of Biosystems Engineering
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    • v.40 no.2
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    • pp.115-123
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    • 2015
  • Purpose: A sampling scheme may significantly affect the accuracy of a sensor. This study was conducted to investigate the effects of sampling point locations on optical reflectance measurements of Chinese cabbage and kale plant leaves. Methods: Variability and similarity of multiple measurements for different parts of the leaves were compared. Results: The results indicate that the variability between the average and individual reflectance spectra was smaller for the blade part than for the vein part. Furthermore, the reflectance for the blade part over the upper leaf area was greater and more stable than those for the other parts for both the cabbage and kale leaf samples. Conclusions: The results provide guidelines for optical reflectance measurements of Chinese cabbage and kale plants. The effects of the number of sampling points, the number of leaves, and the relationships between optical reflectance and leaf components remain to be investigated in the future.

Sampling Methods for Quantification of Solid-state Phases in Powder Samples with Solid-state NMR Spectroscopy

  • Han, Oc-Hee;Kim, Sun-Ha;Ko, Tae-Jung
    • Bulletin of the Korean Chemical Society
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    • v.30 no.5
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    • pp.1077-1079
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    • 2009
  • To minimize the variance in the quantification of solid-state phases in powder samples, gently placing polycrystalline samples one next to another directly in a sample holder is better than trying to mix them homogeneously prior to transferring to a sample holder. However, the solid-state cross polarization-magic angle spinning (CP-MAS) nuclear magnetic resonance (NMR) spectroscopy results demonstrated that it is essential in this sampling method to place all the samples in the location of consistent signal sensitivity. The same sampling method may be employed in other spectroscopic quantification techniques of solid-state phases if the method to limit the sample to the location with uniform signal sensitivity in the sample holder is adapted to each technique.

A Hybrid Algorithm for Online Location Update using Feature Point Detection for Portable Devices

  • Kim, Jibum;Kim, Inbin;Kwon, Namgu;Park, Heemin;Chae, Jinseok
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.2
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    • pp.600-619
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    • 2015
  • We propose a cost-efficient hybrid algorithm for online location updates that efficiently combines feature point detection with the online trajectory-based sampling algorithm. Our algorithm is designed to minimize the average trajectory error with the minimal number of sample points. The algorithm is composed of 3 steps. First, we choose corner points from the map as sample points because they will most likely cause fewer trajectory errors. By employing the online trajectory sampling algorithm as the second step, our algorithm detects several missing and important sample points to prevent unwanted trajectory errors. The final step improves cost efficiency by eliminating redundant sample points on straight paths. We evaluate the proposed algorithm with real GPS trajectory data for various bus routes and compare our algorithm with the existing one. Simulation results show that our algorithm decreases the average trajectory error 28% compared to the existing one. In terms of cost efficiency, simulation results show that our algorithm is 29% more cost efficient than the existing one with real GPS trajectory data.