• Title/Summary/Keyword: Statistical quality control

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Energy efficiency strategy for a general real-time wireless sensor platform

  • Chen, ZhiCong
    • Smart Structures and Systems
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    • v.14 no.4
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    • pp.617-641
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    • 2014
  • The energy constraint is still a common issue for the practical application of wireless sensors, since they are usually powered by batteries which limit their lifetime. In this paper, a practical compound energy efficiency strategy is proposed and realized in the implementation of a real time wireless sensor platform. The platform is intended for wireless structural monitoring applications and consists of three parts, wireless sensing unit, base station and data acquisition and configuration software running in a computer within the Matlab environment. The high energy efficiency of the wireless sensor platform is achieved by a proposed adaptive radio transmission power control algorithm, and some straightforward methods, including adopting low power ICs and high efficient power management circuits, low duty cycle radio polling and switching off radio between two adjacent data packets' transmission. The adaptive transmission power control algorithm is based on the statistical average of the path loss estimations using a moving average filter. The algorithm is implemented in the wireless node and relies on the received signal strength feedback piggybacked in the ACK packet from the base station node to estimate the path loss. Therefore, it does not need any control packet overheads. Several experiments are carried out to investigate the link quality of radio channels, validate and evaluate the proposed adaptive transmission power control algorithm, including static and dynamic experiments.

A Study of Statistical Tools Application - Evaluation of Process Capability - (통계적기법(統計的技法) 활용(活用)에 관(關)한 연구(硏究) - 공정능력평가(工程能力評價)를 중심(中心)으로 -)

  • Seong, Won-Yong;Jung, Soo-Il
    • Journal of the Korea Safety Management & Science
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    • v.10 no.2
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    • pp.195-203
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    • 2008
  • The purpose of this study is to develop a guideline of process capability evaluation and to apply this guideline improving the quality of products, especially in the small and medium enterprises. In this study we deal in the concept of process capability evaluation, the calculation of process capability index, and the application of a case study. Man must compare the state of process with the standards in evaluating of the process capability. Control chart can be used as a yardstick for judgement for the long term period and the distribution shape of histogram for the short term period. Man should regard to the significant figure by the calculation of process capability index.

Developing SPC System of an Automobile Parts Manufacturing Firm under POP System Environment (POP시스템 환경하의 자동차부품 제조업체의 SPC시스템 개발)

  • 이진춘;김정만;김오환
    • Journal of Korea Society of Industrial Information Systems
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    • v.4 no.3
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    • pp.8-14
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    • 1999
  • SPC(Statistical Process Control) provides objective means of controlling quality in any transformation processes by analyzing statistically data gathered in the process. Considering the fact that a measure to feedback results of the process investigation in the real time is required, it is very practical to construct the SPC system as a module of the POP(Point of Production) system. Because this approach can make the investment cost reduced and achieve goals of production/process control and SPC simultaneously. This paper designed and developed the SPC system of firm S that manufactures automobile parts

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Using NIR Spectrometry for Direct Control of Recovered Papers

  • Borel, Pascal;Sabater, Jacques;Tourtollet, Guy Eymin Petot;Cochaux, Alain;Veiga, Joseph
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.39 no.5
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    • pp.58-63
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    • 2007
  • This paper sums up all the different steps broached in this project : The NIR spectroscopy technique has been studied and implemented at CTP using a mobile spectrometer device and different optical materials. Methods, based on statistical data analysis (in particular PLS regressions), have been investigated. A laboratory "prototype" using these techniques and methods has been developed in order to control the recovered papers quality, in terms of humidity percentage and sample composition (paper, board, contaminants).

Automatic Extraction of Size for Low Contrast Defects of LCD Polarizing Film (Low Contrast 특성을 갖는 LCD 편광필름 결함의 크기 자동 검출)

  • Park, Duck-Chun;Joo, Hyo-Nam;Rew, Keun-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.5
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    • pp.438-443
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    • 2008
  • In this paper, segmenting and classifying low contrast defects on flat panel display is one of the key problems for automatic inspection system in practice. Problems become more complicated when the quality of acquired image is degraded by the illumination irregularity. Many algorithms are developed and implemented successfully for the defects segmentation. However, vision algorithms are inherently prone to be dependent on parameters to be set manually. In this paper, one morphological segmentation algorithm is chosen and a technique using frequency domain analysis of input images is developed for automatically selection the morphological parameter. An extensive statistical performance analysis is performed to compare the developed algorithms.

DD-plot for Detecting the Out-of-Control State in Multivariate Process (다변량공정에서 이상상태를 탐지하기 위한 DD-plot)

  • Jang, Dae-Heung;Yi, Seongbaek;Kim, Youngil
    • The Korean Journal of Applied Statistics
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    • v.26 no.2
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    • pp.281-290
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    • 2013
  • It is well known that the DD-plot is a useful graphical tool for non-parametric classification. In this paper, we propose another use of DD-plot for detecting the out-of-control state in multivariate process. We suggested a dynamic version of DD-plot and its accompanying a quality index plot in such case.

An Energy Efficient MAC Protocol Providing Guaranteed Service for Wireless Sensor Network

  • Kim, Dong-Won;Park, Tae-Geon
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.1
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    • pp.123-140
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    • 2011
  • In this paper, we propose an Energy Efficient Media Access Control (EE-MAC) protocol for wireless sensor networks. The proposed scheme is designed to save power consumption and guarantee quality-of-service for real-time traffic. EE-MAC uses the superframe structure which is bounded by the transmission of a beacon frame and can have an active and an inactive portion. The active period is divided into the contention free period (CFP) for real-time traffic transmission and the contention access period (CAP) for non-real-time traffic transmission. We propose the exclusively allocated backoff scheme which assigns a unique backoff time value to each real-time node based on bandwidth allocation and admission control. This scheme can avoid collision between real-time nodes by controlling distributed fashion and take effect a statistical time division multiple access. We also propose the algorithm to change the duty cycle adaptively according to channel utilization of media depending on network traffic load. This algorithm can prolong network lifetime by reducing the amount of energy wasted on idle listening.

The effects of body mass index and body shape perceptions of South Korean adults on weight control behaviors; Correlation with quality of sleep and residence of place

  • Kang, Nam E;Kim, Seung Ju;Oh, Yoon Sin;Jang, Se-Eun
    • Nutrition Research and Practice
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    • v.14 no.2
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    • pp.160-166
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    • 2020
  • BACKGROUND/OBJECTIVES: The obese population is rapidly increasing because of reduced physical activity and a Westernized diet; consequently, various chronic diseases are more prevalent. With the increasing interest in body shape and appearance, research on body shape perceptions and accompanying weight control behaviors are needed for healthy weight management. SUBJECTS/METHODS: A cross-sectional survey was conducted on randomly selected 536 (209 men and 327 women) aged 20 to 65 years. Body mass index (BMI), body-shape perception, weight control behavior, quality of sleep, and place of residence were collected using self-reported questionnaires. Multivariable logistic regression analysis was conducted using complex design in each groups. Collected data were analyzed using the SAS 9.4 statistical package, and the significance level was set at P < 0.05. RESULTS: When these two variables were divided into four groups, they were found to influence dieting attempts. People with abnormal weights who were dissatisfied with their body shapes attempted dieting 5.23 times more than those with healthy weights and satisfaction with their body shapes. Further, those with normal weights but dissatisfaction with their bodies attempted dieting 4.45 times more than those who were satisfied with their shapes. Subjects in their 20s attempted dieting 2.53 times more than those in their 30s and 40s, and female subjects attempted dieting 2.24 times more than male subjects. CONCLUSIONS: A correct perception of one's shape can be an important factor for dietary behavior, as body shape perceptions and dieting attempts are strongly related. Additionally, healthy weight management and nutrition education are important elements to incorporate into a weight control program aimed at preventing excessive weight control behaviors and promoting correct perceptions of body shape.

Effect of natural anti-microbe chemicals, chitosan and stevia, on the growth, yield, and quality of chili peppers

  • Shim, Sang Wan;Kim, Hyuk Jin;Park, Jin Young;Bae, Tae Min;Min, Jeong Ho;Lee, Jin Su;Kim, Sung Joo;Hwang, Yong Soo
    • Korean Journal of Agricultural Science
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    • v.45 no.1
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    • pp.19-27
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    • 2018
  • To study the effect of natural anti-microbial chemicals on the growth and quality of chili peppers, chitosan ($100mg/L^{-1}$), stevia ($250mg/L^{-1}$), and the mixture of both chemicals at the same concentration were sprayed after planting at 1-week interval throughout the experimental period. Plant height was measured twice after the $3^{rd}$ and $4^{th}$ applications. Plant height was numerically reduced in all chemical treatments compared to that of untreated control; however, there was no statistical difference between treatments. The fruit quality was examined at commercial maturity, and only minor differences were found in fruit color, length, and dry matter content between the treatments. Although a statistical difference was not present for soluble sugars levels, total phenolics, and capsaicin contents, yield in all chemical treatments significantly increased compared to untreated control. The effect on yield increase was greater at the late harvest season regardless of treatments. Total yield of 4 harvests was higher for the chitosan treatment than other treatments. During the experiment, the entire experimental field was waterlogged for 1 day due to sudden heavy rainfall, which resulted in the occurrence of bacterial browning disease in all treatments. The rate of disease occurrence and the degree of severity, however, were much lower in the chitosan treatment. In conclusion, the potential of chitosan as an alternative antimicrobial agent was confirmed in chili peppers in this study. Further research is required on stevia as an alternative chemical for disease control in chili peppers.

The Development and Evaluation of Web-based Education Program for Lung Cancer Patient (폐암환자를 위한 웹기반 교육프로그램 개발 및 평가)

  • Yoo, Han-Jin
    • Asian Oncology Nursing
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    • v.5 no.1
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    • pp.11-21
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    • 2005
  • The purpose of this study were to develop an web-based education program for Lung cancer patients and to test its effects on patients' self-care knowledge, compliance to medical regimen, nutrition status and pain. The program was developed by the following process: first, Lung cancer patients demand on the web-based program was investigated. and second, the program was developed with the help of various reference books and then validation of experts group. last, educations effects on the patients is evaluated and compared the differences in self-care knowledge, compliance to medical regimen, nutrition status and pain between on experimental group and a control group on before discharge 1day and 3weeks after. SPSS/Win 11.0 program was used for data analysis. It was proven with $x^2$ test and t-test, and Pearson Correlation coefficient, and Chronbach's alpha coefficient were done for the reliability of measuring instruments. 1. The summary of the Program development is as follows. The program is based on patients' questionnaire and reference material and is made for users friendly. Not only Bigger font size and bright colors but also illustrations or pictures were adopted to help enhance patients' understanding. 2. The summary of the study results is as follows. 1) Compared with control group, the web-based educated experimental group showed a statistical significant difference on self-care knowledge, Especially disease, radiation treatment, medication & analgesics, chemotherapy side effect, but there was no significant difference in the field of chemotherapy, in the fields of operation, diet & general knowledge. 2) Compared with control group, the web-based educated experimental group showed a statistical significant difference on compliance to medical regimen, especially in the field of follow up care, everyday life, diet, but there was no significant difference in the field of medication, exercise. 3) Compared with control group, web-based educated experimental group showed no significant difference in nutrition status, but partially significant difference in body weight. 4) Compared with control group, the web-based educated experimental group showed no significant difference in pain level. 5) The significantly positive correalation self-care knowledge with the compliance to medical regimen. 6) Users satisfaction with the web-based education program of the contents quality, the level of recommendation to others, content layout, medical information quality, but interesting got a low mark.

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