• Title/Summary/Keyword: Quality time

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Optimization of Multiple Quality Characteristics for Polyether Ether Ketone Injection Molding Process

  • Kuo Chung-Feng Jeffrey;Su Te-Li
    • Fibers and Polymers
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    • v.7 no.4
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    • pp.404-413
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    • 2006
  • This study examines multiple quality optimization of the injection molding for Polyether Ether Ketone (PEEK). It also looks into the dimensional deviation and strength of screws that are reduced and improved for the molding quality, respectively. This study applies the Taguchi method to cut down on the number of experiments and combines grey relational analysis to determine the optimal processing parameters for multiple quality characteristics. The quality characteristics of this experiment are the screws' outer diameter, tensile strength and twisting strength. First, one should determine the processing parameters that may affect the injection molding with the $L_{18}(2^1{\times}3^7)$ orthogonal, including mold temperature, pre-plasticity amount, injection pressure, injection speed, screw speed, packing pressure, packing time and cooling time. Then, the grey relational analysis, whose response table and response graph indicate the optimum processing parameters for multiple quality characteristics, is applied to resolve this drawback. The Taguchi method only takes a single quality characteristic into consideration. Finally, a processing parameter prediction system is established by using the back-propagation neural network. The percentage errors all fall within 2%, between the predicted values and the target values. This reveals that the prediction system established in this study produces excellent results.

Investigation on the Scrum-based Standard Management for Efficient Data Quality Control of Small-sized Companies : A Case Study on Distribution Service of Company 'I' (중소기업의 효율적 데이터 품질관리를 위한 스크럼 기반 표준관리 방안 : 'I'사 물류서비스 적용 사례)

  • Kim, Tai-Yun;Kim, Nam-Gyu;Sohn, Yong-Lak
    • Journal of Information Technology Applications and Management
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    • v.17 no.1
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    • pp.83-105
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    • 2010
  • The competence of enterprise for managing information is evaluated not by the amount of information but by the quality of information such as response time, data consistency, and data correctness. The degradation of data quality is usually caused by the inappropriate process of managing the structure and value of stored data. According to the recent survey on the actual condition of data quality management, the correctness and consistency of data appeared to be the most problematic area among the six criteria of data quality management such as correctness, consistency, availability, timeliness, accessibility, and security. Moreover, the problem was more serious in case of small and medium-sized companies than large enterprises. In this paper, therefore, we attempt to propose a new data quality control methodology for small and medium-sized companies that can improve the correctness and consistency of data without consuming too much time and cost. To adopt the proposed methodology to real application immediately, we provided some scripts for as-is analysis and devised automation tools for managing naming rules of vocabulary, terminology, and data code. Additionally, we performed case study on the distribution service of a small-sized company to estimate the applicability of our tool and methodology.

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Factors Relating to Quality of Life in Korean Breast Cancer Patients: Systematic Review and Meta-analysis (한국 유방암 환자의 삶의 질에 대한 관련요인: 체계적 문헌고찰과 메타분석)

  • Park, Kyung-Yeon;Kim, Minju;Yang, Young Ok
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.24 no.2
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    • pp.95-105
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    • 2017
  • Purpose: A systematic literature review and meta-analysis were conducted to synthesis research findings on relationships of quality of life with multi-dimensional correlates in Korean breast cancer patients. Methods: For the study purpose, 18 studies were selected through a systematic process of searching the literature. Results: Among the general characteristics, variables having a significant relationship with quality of life were age (ES=.19), marital status (ES=.15), education (ES=.19), economic status (ES=.16), job status (ES=.10), and religion (ES=.13). Among the disease characteristics, type of treatment (ES=.12), length of time since diagnosis (ES=.13), stage of disease (ES=.14), length of time since operation (ES=.10), frequency of treatment (ES=.19), wound site and pain (ES=.16) were shown to have a significant relationship with quality of life. Depression (ES=-.60), one of the psychological factor, was the variable most significantly related to quality of life. Conclusion: The findings indicate that the variables which strongly impact quality of life in breast cancer patients are depression and pain.

Agent-based Adaptive Multimedia Streaming Considering Device Capabilities and Dynamic Network Conditions (무선 단말의 처리능력과 동적 네트워크 환경을 고려한 에이전트 기반의 적응적 멀티미디어 스트리밍 기법)

  • Jang, Minsoo;Seong, Chaemin;Kim, Jingu;Lim, Kyungshik
    • IEMEK Journal of Embedded Systems and Applications
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    • v.10 no.6
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    • pp.353-362
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    • 2015
  • In order to provide smart devices with high quality multimedia streaming services, an adaptive streaming technique over HTTP has been received much attention recently and the Dynamic Adaptive Streaming over HTTP (DASH) standard has been established. In DASH, however, the technique to select an appropriate quality of multimedia based on the performance metrics measured in a smart device might have some difficulties to reflect the capabilities of other neighboring smart devices and dynamic network conditions in real time. To solve the problem, this paper proposes a novel software agent approach, called DASH agent (DA), which gathers and analyzes the device capabilities and dynamic network conditions in real time and finally determines the highest achievable quality of segment to meet the best Quality of Experience (QoE) in current situations. The simulation results show that our approach provides higher quality of multimedia segments with less frequency of quality changes to lower quality of multimedia segments.

Evaluation of the Dam Release Effect on Water Quality using Time Series Models (시계열 모형의 적용을 통한 댐 방류의 수질개선 효과 검토)

  • Kim, Sangdan;Yoo, Chulsang
    • Journal of Korean Society on Water Environment
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    • v.20 no.6
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    • pp.685-691
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    • 2004
  • Water quality forecasting with long term flow is important for management and operation of river environment. However, it is difficult to set up and operate a physical model for water quality forecasting due to large uncertainty in the data required for model setting. Therefore, relatively simpler stochastic approaches are adopted for this problem. In this study we try several multivariate time series models such as ARMAX models for the possible substitute for water quality forecasting. Those models are applied to the BOD and COD levels at Noryangin station, Han river, and also evaluated the effect of release from Paldang dam on them. Monthly BOD and COD data from 1985 to 1991 (7 years) are used for model building and another two year data for model testing. As a result of the study, the effect of improvement on water quality is much more effective combining with the water quality improvement of dam release than considering only increment of dam release in the downstream Han river.

Changes in the Grain Quality of Rice with Respect to the Duration of Lodging Time

  • Hwang, Tai-Jeong;Lee, Won-Jong;Shin, Jin-Chul;Lee, Chul-Won;Kim, Suk-Shin
    • Food Science and Biotechnology
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    • v.18 no.6
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    • pp.1459-1463
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    • 2009
  • The specific objective of this study was to determine the changes in grain quality of lodged rice with respect to the duration of lodging time and compare the changes with those of unlodged one. The rice 'Janganbyeo' was cultivated and half of paddy field was totally lodged at 30 days after heading. Both lodged paddy and unlodged paddy were harvested at intervals and used for the grain quality determination. The lodged rice did not show any remarkable changes in grain quality until the $4^{th}$ day of lodging for rough rice and until the $2^{nd}$ or the $4^{th}$ day of lodging for brown rice and white rice. The overall grain quality of lodged rice could be kept for 2 to 4 days of lodging.

Effects of respiratory reeducation exercise using a pressure biofeedback unit on the quality of life of persons with stroke

  • Kim, Hyun Seung
    • Physical Therapy Rehabilitation Science
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    • v.9 no.4
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    • pp.238-243
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    • 2020
  • Objective: The purpose of this study was to confirm the validity of a respiratory retraining exercise using pressure biofeedback units among individuals with stroke as an effective intervention for improving quality of life. Design: Randomized controlled trial. Methods: Thirty patients with stroke were recruited as subjects. Among them, 15 patients were randomly assigned to an experimental group performing lumbar stabilization exercise and respiratory retraining exercise, and the other 15 patients were randomly assigned to a control group conducting only lumbar stabilization exercises. Exercises were conducted 3 times a week for 6 weeks, and quality of life was evaluated in the pre-test, 3 weeks and 6 weeks periods. The respiratory retraining exercises were performed using a pressure biofeedback unit and the degree of the quality of life was measured using the Stroke- Specific Quality of Life. For data analysis on the study results, a two-way repeated ANOVA was used in order to observe for changes in the measured variables according to time for both groups. If there was a reciprocal action between the groups and the time in the effect test within the entities, a one-way repeated ANOVA was implemented and was statistically processed. Results: There was a significant difference in the main effect test between the 2 populations depending on the duration of the experiment (6 weeks) (p<0.05). Conclusions: The above results showed that respiratory retraining exercises may provide positive effects in the treatment of stroke as the quality of life showed significant differences according to the duration of treatment.

Effects of Sleep on Balance Control and Reaction Time to Visual Stimuli (수면이 균형조절과 시각적 자극 반응시간에 미치는 영향)

  • Park, Sookyoung;Park, Jung-A;Park, Kanghui;Kim, Joo-Heon;Hong, Yonggeun
    • Sleep Medicine and Psychophysiology
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    • v.23 no.2
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    • pp.68-76
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    • 2016
  • Objectives: To find evidence that sleep is necessary for normal brain function, thus indicating that declines in both sleep quality and quantity are related to worse performance of many daily tasks and deteriorated physical functions. The present study investigates the relationships of balance control and reaction time with sleep quality. Methods: 58 healthy (male 20, female 38) volunteers with informed consent participated in this study. The Self-reported Pittsburgh Sleep Quality Index (PSQI) was used to evaluate sleep quality and relevant factors, and the subjects were divided into groups A (PSQI < 5) and B ($PSQI{\geq}5$) based on this index. Static balance control and reaction time to visual stimuli were conducted to assess their relationship with sleep quality. Results: Group B exhibited excessive daytime sleepiness significantly more often compared to group A. Static balance control did not markedly change relative to sleep quality, but reaction time and error to visual stimuli were significantly increased in group B compared to group A. Conclusion: These findings indicate that a decline in sleep quality can result in delayed reactions, as well as decreased accuracy of these reactions. They also suggest that low sleep quality may be associated with changes in physical functions, including balance control through reduced selective attention.

Accuracy Analysis of Network-RTK(VRS) for Real Time Kinematic Positioning (실시간 이동 측위 적용을 위한 Network-RTK(VRS) 정확도 분석)

  • No, Sun-Joon;Han, Joong-Hee;Kwon, Jay Hyoun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.30 no.4
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    • pp.389-396
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    • 2012
  • As the demand on the precise positioning for the moving objects has been increased in the various industry field, many studies have been conducted to analyze real time kinematic technique and its practical usage. The main purpose of this study is to analyze the possibility of Network-RTK(VRS) in real-time kinematic positioning. So, the accuracy analysis has been conducted by comparing the Network-RTK(VRS) position with respect to the RTK position. As a result, Network-RTK(VRS) based on kinematic positioning has centimeter level of RMS in the ideal environment compared to RTK positioning. However, when the integer ambiguities was lost, the accuracy of Network-RTK was meter level. At that time, the quality value has been changed dramatically and shows big correlation with accuracy. When the position and height quality values are within 0.1m, the RMS of the horizontal and vertical position appears better than 10cm and 20cm, respectively. However, if the quality value is over 0.1m, the RMS increases to larger than a meter. Therefore, it is recommended to check the quality value when conducting Network-RTK(VRS) kinematic positioning to get the centimeter level accuracy.

Effect of Transplant and Harvest Time on Grain Quality of Rice in Reclaimed Paddy Field (간척지에서 이앙기 및 수확시기가 쌀의 품질 특성에 미치는 영향)

  • Je-Cheon Chae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.48 no.6
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    • pp.534-539
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    • 2003
  • The yield and quality characteristics of three rice varieties(Seojinbyeo, Ilpumbyeo, and Chuchungbyeo) in reclaimed saline paddy field were investigated under different cultural practices, three transplanting times (May 15, May 30 and June 15) and four harvest times (40, 50, 60 and 70days after heading) in order to obtain basic information for the production of high quality rice. Brown rice yield of three rice varieties were significantly higher in early and medium than late season cultivation. The protein content of milled rice showed high interaction effect between transplanting time and harvest time. Palatability values of Seojinbyeo and Ilpumbyeo were significantly higher in late than medium season cultivation, but Chucheongbyeo did not show any difference in its palatability value by different transplanting time. The palatability values of three rice variety was the highest in the harvest at 40 days after heading. The grain yield of three rice varieties were higher in early and medium than late season cultivation, whereas palatability values of three rice varieties were significantly higher in the early and late season cultivation than medium season cultivation. The palatability value measured by rice taster showed a highly negative correlation(r=$0.43^{**}$) with cumulative air temperature during ripening period.