• 제목/요약/키워드: Statistical surveys

검색결과 509건 처리시간 0.023초

Statistical Analysis of a Subjective QoE Assessment for VVoIP Applications

  • Cano, Maria-Dolores;Cerdan, Fernando;Almagro, Sergio
    • ETRI Journal
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    • 제32권6호
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    • pp.843-853
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    • 2010
  • A successful deployment of multimedia applications over wireless environments entails improving the quality of service (QoS), not only from a technical point of view, but also considering the quality of experience (QoE) from the final user's perception. Although objective QoE measure models avoid the difficulties of subjective surveys, subjective QoE assessments are essential to understand the way users evaluate the QoS. In this work, we study the effect of a wide range of parameters on the QoE of VVoIP applications in a real wireless scenario. Through a complete statistical analysis of users' ratings, we identify the following facts. Although the use of VVoIP in wireless networks does not yet represent an advantage for users, there are great expectations for all applications under study, and with greater popularity comes higher expectations. It is easier for respondents to identify good behavior than poor behavior. Whereas the respondents' frequency of Internet use does not impact on the scores, respondents' gender does. Finally, the most determining parameters of quality from a user's perspective were instability, video quality, voice distortion, usefulness, and graphical interface.

Investigation of Water Safety in Non-treated Drinking Water with Trace Toxic Metals

  • Ly, Suw Young;Kim, Dae Hong;Lee, Ga Eun
    • Toxicological Research
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    • 제29권3호
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    • pp.211-215
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    • 2013
  • The trace toxic metal copper was assayed using mercury immobilized on a carbon nanotube electrode (MCW), with a graphite counter and a reference electrode. In this study, a macro-scale convection motor was interfaced with a MCW three-electrode system, in which a handmade MCW was optimized using cyclic- and square-wave stripping voltammetry. An analytical electrolyte for tap water was used instead of an expensive acid or base ionic solution. Under these conditions, optimum parameters were 0.09 V amplitude, 40 Hz frequency, 0.01 V incremental potential, and a 60-s accumulation time. A diagnostic working curve was obtained from 50.0 to 350 ${\mu}g/L$. At a constant Cu(II) concentration of 10.0 ${\mu}g/L$, the statistical relative standard deviation was 1.78% (RSD, n = 15), the analytical accumulation time was only 60 s, and the analytical detection limit approached 4.6 ${\mu}g/L$ (signal/noise = 3). The results were applied to non-treated drinking water. The content of the analyzed copper using 9.0 and 4.0 ${\mu}g/L$ standards were 8.68 ${\mu}g/L$ and 3.96 ${\mu}g/L$; statistical values $R^2$ = 0.9987 and $R^2$ = 0.9534, respectively. This method is applicable to biological diagnostics or food surveys.

대규모 표본설계에서 확률비례 및 단순집락추출법 비교 -경제활동인구 표본조사 사례를 중심으로- (A Comparison of PPS and Simple Cluster Sampling in Large Scale Sampling -Based on Economically Active Population Survey Sample Design)

  • 윤연옥;이상은
    • 응용통계연구
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    • 제14권1호
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    • pp.1-11
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    • 2001
  • 확률비례추출법(pps sampling)에서 표본단위의 추출확률을 결정하기 위하여 크기측도(measure of size:MOS)를 사용한다. 통계청에서 실시하는 일부 대규모조사의 경우 각 표본단위들의 크기측도를 살펴보면 서로 매우 유사한 편임을 알 수 있다. 이런 경우 조사원 업무량을 고려하여 확률비례추출법 대신 단순집락추출법의 사용 필요성이 제시되었다. 본 논문에서는 1997년 통계청의 경제활동인구조사 표본설계법에 두 가지 추출법을 적용하여 평균제곱오차(MSE)와 변이계수(CV)를 비교하였다.

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Prospects and Challenges of Social Media Marketing: Study of Indian Management Institutes

  • Bhandari, Ravneet Singh;Bansal, Sanjeev
    • Asian Journal of Business Environment
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    • 제8권4호
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    • pp.5-15
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    • 2018
  • Purpose - The research aimed to reveal real decisional behavioral of management institutes in India for social media marketing usage, and analyses of empirical elements of social media consumption pattern. Research design, data, and methodology - The investigation was based around a research methodology using quantitative analysis with appropriate statistical techniques on random surveys of consumers, detailed exploratory and confirmatory factor analyses are applied to assess the empirical validity of the model and multiple regression employed using R studio edition to validate the reliability of the developed models. Results - A new conceptual framework is proposed - the management institutions decision model, providing a tool for effective and more focused decision-making strategies for developing better utilization techniques for social media. Management institutions have different requirements based upon objectives and resources available. The evidence suggests that the administrators need to be more aware of consumer indicators when targeting and designing social media marketing strategy. Conclusions - The research was based on samples and not the entire population of target consumers, providing limitations. As an inferential statistical method was chosen, the results might be susceptible to inaccuracy. The model developed from different age users, thereby providing rich perspectives into social media usage pattern.

한의약 분야 통계 개선방안에 관한 연구 (A Study on the Development of Statistics in Korean Medicine)

  • 김대영;오윤정;문혜선;한창연
    • 한국한의학연구원논문집
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    • 제13권1호통권19호
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    • pp.125-128
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    • 2007
  • Objective : This study aims to review the current status and problems of Korean Medicine and attempts to come up with the means to present a comprehensive and effective set of statistical data. Methods : We have analyzed the current statistics and tried to show how to establish an effective system to gather and organize statistics related to Korean Medicine, including national surveys by the Ministry of Health and Welfare or other relevant insititutions. Results : The existing statistics in Korean Medicine were established not as a result of national demand based on comprehensive analysis but due to the demand of the government ministries such as the Ministry of Health and Welfare or other relevant institutions. Thus, the statistics have been revealed to possess limitations such as a lack of systemization and consistency. In addition, the statistics analyze only the current industrial status of Korean Medicine, and as a result the information in unable to show systematic data for innovation, which is indispensable for the advancement and development of the Korean Medicine industry. Conclusion : To improve the statistical data in Korean Medicine, the statistics need to get over not only the level of management or regulation in Korean Medicine, but also the production of fragmentary statistics. It has to ultimately reflect the innovative activities in Korean Medicine nationally, and show what we need to advance and develop the industry.

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Korean country-specific-advantage factors on Chinese consumer's buying intention of Korean rice: focus on the Shanghai area

  • Yang, Suk-Joon
    • 농업과학연구
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    • 제46권4호
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    • pp.915-930
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    • 2019
  • The purpose of this study was to investigate how subcategories of the country-specific-advantage (CSA), which has been discussed in previous studies, affect the buying intention of Korean rice. After reviewing existing studies and examining research models based on them, a research model was verified by questionnaires and statistical analysis. The results of the surveys and statistical analyses reveal that the CSA factors presented in previous studies can also be applied in the context of Korean rice products. The results show that environmental resource, cultural resource and visual element factors influenced the buying intention through perceived quality. In addition, cultural resource perception factors have a direct effect on buying intention. This is consistent with previous studies showing that emotional communication approaches are ineffective for products that are perceived to have functional characteristics. Based on the results of this study, it was confirmed that CSA factors are suitable for the product and export target area. Strategic implications are suggested in that it is necessary to build marketing strategies to improve the perceived quality by the four factors. The theoretical implications are as follows. The sub-factors that constitute COI may have a negative effect and a positive effect; thus, it is necessary to utilize CSA when considering the product and country characteristics. The CSA factors revealed in previous studies are also significant in other regions and products. Finally, the theoretical implication is that consumers use CSA as a clue to evaluate quality.

Change of Intrinsic Brightness Temperatures of Compact Radio Jets

  • Lee, Sang-Sung
    • 천문학회보
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    • 제39권2호
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    • pp.57.1-57.1
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    • 2014
  • We present results of our investigation of intrinsic brightness temperatures of compact radio jets at radio frequencies. The intrinsic brightness temperatures of about 100 compact radio jets at 2, 5, 8, 15, and 86 GHz are estimated based on large VLBI surveys conducted in 2001-2003 (or in 1996 for the 5 GHz sample). The multi-freqeuncy intrinsic brightness temperatures of the sample of the jets are determined with a statistical method relating the observed brightness temperatures with the maximal apparent jet speed, assuming one representative intrinsic brightness temperature for the sample at each observing frequency. With investigating the observed brightness temperatures at 15 GHz in multiple epochs, we found that the determination of the intrinsc brightness temperature for our sample is affected by variability of individual jets in flux density at the time scales of a few years. This implies an importance of contemporaneity of the multi-frequency VLBI observations for the statistical method. Since our analysis is based on the VLBI observations conducted in 2001-2003, the results are less affected by the flux density variability. We found that the intrinsic brightness temperature $T_0$ increases as $T_0{\propto}{\nu}^{\epsilon}$ with ${\epsilon}{\approx}0.7$ below a critical frequency ${\nu}_c{\approx}10GHz$ where energy losses begin to dominate the emission, and above the critical frequency, $T_0$ decreases with ${\epsilon}{\approx}-1.2$ supporting for the decelerating jet model.

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치과기공의 디지털화에 대한 치과기공사의 인식에 관한 연구 - 대구.경북지역 치과기공소를 중심으로 - (A Study on the Dental Technician's Perception of the Digitalization of Dental technology (Centered on the Dental Laboratories in Daegu-Gyeongbuk))

  • 이종도;박광식
    • 대한치과기공학회지
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    • 제33권3호
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    • pp.247-256
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    • 2011
  • Purpose: The purpose of this survey research was to investigate the Perception level of CAD/CAM of dental techique. Methods: This survey was carried out in the metropolitan areas of the cities of Daegu and Gyeong-buk. Surveys were filled out by consenting dental technicians. Statistical analysis was done using the Statistical Package for Social Sciences (SPSS) version 17.0 for Windows. As for the analysis methods, the study used the frequency analysis, Ttest, F-test. Results: Perception of CAD/CAM showed differences in General characteristics associated with education level, monthly salary. Perception of CAD/CAM showed differences in professional characteristics associated with working area, working part. Perception of CAD/CAM showed differences in understanding of CAD/CAM associated with CAD/CAM operating experience, CAD/CAM educational experience. Conclusion: In order to improve the Perception level of CAD/CAM of dental technician, A variety education and follow-up research is need.

치과기공소의 특성에 따른 치과보철물의 재제작에 관한 연구 - 대구.경북 치과기공소 중심으로 - (A Study on Remake of Dental Prosthesis According to Dental Laboratory Characteristics (Focusing on Daegu and Gyeong-buk of Dental lab))

  • 김정숙;이희성
    • 대한치과기공학회지
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    • 제33권3호
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    • pp.227-236
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    • 2011
  • Purpose: The purpose of this study was to reduce the remake rate of dental prosthesis. We examined remake cause and major factor of dental prosthesis to determine methods for raising dental prosthesis satisfaction. Methods: Subjects included dental technicians in the metropolitan areas of the cities of Daegu and Gyeong-buk. Surveys were filled out by consenting dental technicians. Statistical analysis was done using SPSS version 19.0 for Windows. We determined frequencies and percentage, calculating means, and standard deviations, and determining statistical significance using t-tests, analysis of variance. Results: Impression or material transform is high among remake cause and margin is high among remake major factor. Crown class showed differences in General characteristics associated with age, number of employees, and number of connection dental. Porcelain class showed differences in General characteristics associated with age, number of employees, and number of connection dental. Denture class showed differences in General characteristics associated with age, monthly salaray, and career. Implant class showed differences in General characteristics associated with age, education, and career. Conclusion: In order to reduce remake rate of dental prosthesis, communication of dentist, dental technician, and the patient are require and correct information of patient and dental prosthesis are need.

친환경농산물 유통경로별 취급 비중과 특성 분석 (Analysis of Characteristic and Proportion treated by Distribution Channels for Environment-friendly Agricultural Products)

  • 최병옥;김호;이기현
    • 한국유기농업학회지
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    • 제22권1호
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    • pp.25-46
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    • 2014
  • Since organized living cooperative associations sold their environment-friendly agricultural products directly to independent consumers in the past, the general distribution channels such as wholesalers had difficulty in handling these products. However, the ratio of distribution via wholesale channel has been gradually increased as consumption of environment-friendly agricultural products has expanded. This study is to address vitalization of wholesale distribution for environment-friendly agricultural products by gathering previous statistical data and analysis. In addition, statistical analysis are conducted by utilizing surveys on forwarders, consumers for environment-friendly agricultural products. As a result, the products producers ship are distributed through dealers at producers sites, producers cooperatives, or food process companies, food companies, internet shopping malls, large-scale distribution companies, consumer groups such as living cooperative associations, direct outlets at consumers sites, or exports. Among the channels, the large-scale distribution companies and franchised special shops account for 47%, the general supermarkets 15.7%, and living cooperative associations 14.6% respectively. By utilizing the research results on producers and consumers, and the distribution weight by channels for environment-friendly agricultural products, the distribution channels for living cooperative associations, wholesale markets, and large scale distribution companies are compared and evaluated. As a result, the level of producers' and consumers' satisfaction for them is the lowest since the low selling price for producers and high distribution margins.