• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.155-159
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• 2004

In this paper, it was analyzed the characteristics of electrical and acoustical variations for loudspeaker due to fabrication processes. First, mass of each components of loudspeaker was measured by electric precision scale and performed statistical analysis. Second. Thiele-Small parameters of sample loudspeakers produced by unskilled students were identified by known mass parameter identification method using electrical impedance method and investigated on the variations of each parameter. Electrical impedance tests and acoustic frequency responses were measured on sample loudspeakers and variations were examined to grasp relationship between components variation and fabrication processes. Main factors to effect the changes of electrical impedance were concluded by fabrication processes errors not by components of loudspeaker.

• International Journal of Computer Science & Network Security
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• v.22 no.12
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• pp.19-28
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• 2022

The study aimed to identify the impact of Applications of Internet of things on practice of knowledge management in organizations: the mediating role of employees' Engagement. A quantitative questionnaire survey is conducted. The study population consisted of all senior and middle administrations in small and medium enterprises in Jordan. The study sample consisted of (350) senior and middle administrations. The study sample was selected by random stratified method. The results revealed that There is an impact of Applications of Internet of things on the practice of knowledge management at (α ≤ 0.05) in the small and medium enterprises in Jordan. Furthermore, there is an impact of Applications of Internet of things on the employees' Engagement. The current study provided some important insights into an issue that requires further research. Understanding the applications of the Internet of Things and their impact on improving knowledge management is of paramount importance in raising the quality of products and improving the company's image, as shown in this research.

• Communications for Statistical Applications and Methods
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• v.30 no.4
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• pp.403-410
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• 2023

Two-Phase sampling, which was first introduced by Neyman (1938), has various applications in different forms. Variance estimation for two-phase sampling has been an important research topic because conventional variance estimators used in most softwares are not working. In this paper, we considered a variance estimation for two-phase sampling in which stratified two-stage cluster sampling designs are used in both phases. By defining a conditionally unbiased estimator of an approximate variance estimator, which is calculable when all elements in the first phase sample are observed, we propose an explicit form of variance estimator of the double expanded estimator for a two-phase sample. A small simulation study shows the proposed variance estimator has a negligible bias with small variance. The suggested variance estimator is also applicable to other linear estimators of the population total or mean if appropriate residuals are defined.

• Journal of the Korean Data and Information Science Society
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• v.27 no.6
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• pp.1621-1629
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• 2016

This paper studies Bayesian pooling for analysis of categorical data from small areas. Many surveys consist of categorical data collected on a contingency table in each area. Statistical inference for small areas requires considerable care because the subpopulation sample sizes are usually very small. Typically we use the hierarchical Bayesian model for pooling subpopulation data. However, the customary hierarchical Bayesian models may specify more exchangeability than warranted. We, therefore, investigate the effects of pooling in hierarchical Bayesian modeling for the contingency table from small areas. In specific, this paper focuses on the methods of direct or indirect pooling of categorical data collected on a contingency table in each area through Dirichlet priors. We compare the pooling effects of hierarchical Bayesian models by fitting the simulated data. The analysis is carried out using Markov chain Monte Carlo methods.

• Asia pacific journal of information systems
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• v.14 no.3
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• pp.145-167
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• 2004

Given the increasing of adoption of the SCM(Supply Chain Management), especially in small and medium-sized enterprises, this study aims at identifying the key influencing factors of small and medium-sized enterprises' SCM adoption. Based on prior research on innovation diffusion theory, TPB(Theory of Planned Behavior), and IT/EDI adoption in various organizations, a model of SCM adoption has been developed and empirically tested hypotheses based on the model. The model was tested using LISREL analysis on the sample collected from 127 small and medium-sized enterprises' top management. The results show that perceived behavioral control is found to have a significant positive effect on adoption intention, and attitude and subjective norm are also important determinants of SCM adoption intention in small and medium-sized enterprises. Implications of these findings are discussed for researchers and practitioners.

• Journal of Distribution Science
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• v.13 no.4
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• pp.29-33
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• 2015

Purpose - This paper aims to explain the interactive relationship between small and medium-sized enterprises' clusters and regional economic growth, with Jiangsu Province as an illustrative example. It focuses on studying the promotional effects, if any, of small and medium-sized enterprises' cluster-development on regional economic growth, and vice-versa. Research design, data, and methodology - Data were collected from the Jiangsu Statistical Yearbook and the China Industrial Economic Statistical Yearbook, by selecting 26 industries as the research subjects. The sample interval selection is 1981-2012. The data were analyzed with the dynamic panel system using stata 12.0. Results - 1) The small and medium-sized enterprises' cluster degree and Jiangsu's economic growth have a long-term stable equilibrium relationship. 2) In the short term, they have a dynamic adjustment 3) The enterprises' cluster degree leads to regional economic growth in Jiangsu, but not vice-versa. Conclusions - Small and medium-sized enterprises' clusters have an important promotional effect on Jiangsu's economic growth, especially industries with high degree of agglomeration. Therefore, the formation of these clusters can significantly improve economic growth.

• Journal of Soil and Groundwater Environment
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• v.18 no.1
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• pp.94-101
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• 2013

It is well known that uncertainty associated with soil sampling is bigger than that with analysis. In this research, uncertainties for soil sampling when assessing TPH and BTEX concentration in soils were quantified based on actual field data. It is almost impossible to assess exact contamination of the site regardless how carefully devised for sampling. Uncertainties associated with sample reduction for further chemical analysis were quantified approximately 10 times larger than those associated with core sampling on site. Bigger uncertainties occur when contamination level is low, sample quantity is small, and soil particle is coarse. To minimize the uncertainties on field, homogenization of soil sample is necessary and its procedures are proposed in this research as well.

• ETRI Journal
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• v.34 no.6
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• pp.974-977
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• 2012

In this letter, a small-sized ultra-high frequency (UHF) RFID tag antenna for a medical sample tube is proposed. The RFID tag antenna is designed and fabricated based on the circular loop antenna used in the UHF band (Korea standard, 917 MHz to 923.5 MHz). The tag antenna size is reduced using a circular meander stub. The antenna has a physical size of 8 mm, which is about ${\lambda}$/40 in electrical length. The proposed tag antenna is molded into a medical sample and multitag identification is performed.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.1
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• pp.67-76
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• 2000

Dyeing fastness and antibiosis effects of fabrics dyed with wormwood, which has been used in folk medicines and dietary life in Korea for a long time, were studied through dyeing small overcoats, which are used as diapers, with wormwood extract. As for the dying fastness test results, the fastness of decoloration was not that good but the pollution level showed a relatively positive result. As for the antibiosis effect results, the antibiosis of the dyed sample was better than the original sample on 3 kinds of bacteria, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and on 2 kinds of the fungi(Eumycetes). Aspergillus niger and Candida albicans. Especially, the sample that was mordant with CaCl2 and FeSO4·7H2O showed the best antibiosis effect. On the other hand, the sample that showed the best antibiosis effect was the refined fabric, which is a fabric that is not dyed.

• Applied Microscopy
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• v.46 no.2
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• pp.110-115
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• 2016

Transmission electron microscopy (TEM) is a powerful tool for analyzing a broad range of materials and provides localized information about the microstructure. However, the analysis results are strongly influenced by the quality of the thin foil specimen. Sample preparation for TEM analysis requires considerable skill, especially when the area of interest is small or the material of interest is difficult to thin because of its high hardness and its mechanical instability when thinned. This article selectively reviews recent advances in TEM sample preparation techniques using a tripod polisher. In particular, it introduces two typical types (fl at type and wedge type) of TEM sample preparation and the benefits and drawbacks of each method; finally, a method of making better samples for TEM analysis is suggested.