• Title/Summary/Keyword: Quality control parameters

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Design of Interworking Control System between QoS Parameters and QoE Items to Control Multimedia Services Quality (멀티미디어 서비스 품질 제어를 위한 QoS 파라미터와 QoE 요소간의 연동 제어 시스템 설계)

  • Kim, Hyun-Jong;Yun, Dong-Geun;Choi, Seong-Gon
    • The Journal of the Korea Contents Association
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    • v.10 no.4
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    • pp.45-54
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    • 2010
  • In this paper, we propose a quality interworking control system to enhance user's quality satisfaction in NGN environment by controling QoS parameters related with QoE in network layer when service user's QoE using variance multimedia service is poor. The proposed system gathers QoS parameter information in network layer through control packet such as RTCP, and evaluates QoE of multimedia service using these QoS parameter information. Comparing the evaluated QoE with the measured QoE in application layer, QCS judges quality degradation, deduces related QoS parameters and decides relative importance of each parameter when QoE is lower than threshold value. QCS generates QoS control values which is based on routing and switching policy in service quality control system(SCS) and forwards them to SCS. Through this proposed system, service and network providers can provide multimedia services of enhanced quality to service users taking account of service characteristic and network performance.

Effect of fermented biogas residue on growth performance, serum biochemical parameters, and meat quality in pigs

  • Xu, Xiang;Li, Lv-mu;Li, Bin;Guo, Wen-jie;Ding, Xiao-ling;Xu, Fa-zhi
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.10
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    • pp.1464-1470
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    • 2017
  • Objective: This study investigated the effect of fermented biogas residue (FBR) of wheat on the performance, serum biochemical parameters, and meat quality in pigs. Methods: We selected 128 pigs (the mean initial body weight was $40.24{\pm}3.08kg$) and randomly allocated them to 4 groups (1 control group and 3 treatment groups) with 4 replicates per group and 8 pigs per pen in a randomized complete block design based on initial body weight and sex. The control group received a corn-soybean meal-based diet, the treatment group fed diets containing 5%, 10%, and 15% FBR, respectively (abbreviated as FBR5, FBR10, and FBR15, respectively). Every group received equivalent-energy and nitrogen diets. The test lasted 60 days and was divided into early and late stages. Blood and carcass samples were obtained on 60 d. Meat quality was collected from two pigs per pen. Results: During the late stage, the average daily feed intake and average daily gain of the treatment groups was greater than that of the control group (p<0.05). During the entire experiment, the average daily gain of the treatment groups was higher than that of the control group (p<0.05). Fermented biomass residue did not significantly affect serum biochemical parameters or meat quality, but did affect amino acid profiles in pork. The contents of Asp, Arg, Tyr, Phe, Leu, Thr, Ser, Lys, Pro, Ala, essential amino acids, non-essential amino acids, and total amino acids in pork of FBR5 and FBR10 were greater than those of the control group (p<0.05). Conclusion: These combined results suggest that feeding FBR could increase the average daily gain and average daily feed intake in pigs and the content of several flavor-promoting amino acids.

Estimation of Hardened Layer Dimensions Using Multi-Point Temperature Monitoring in Laser Surface Hardening Processes (레이저 표면 경화 공정에서 다점 온도 모니터링을 통한 경화층 크기 예측)

  • 우현구
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.12
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    • pp.1048-1054
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    • 2003
  • In laser surface hardening processes, the geometrical parameters such as the depth and the width of a hardened layer can be utilized to assess the hardened layer quality. However, accurate monitoring of the geometrical parameters for on-line process control as well as for on-line quality evaluation is very difficult because the hardened layer is formed beneath a material surface and is not visible. Therefore, temperature monitoring of a point of specimen surface has most frequently been used as a process monitoring method. But, a hardened layer depends on the temperature distribution and the thermal history of a specimen during laser surface hardening processing. So, this paper describes the estimation results of the geometric parameters using multi-point surface temperature monitoring. A series of hardening experiments were performed to find the relationships between the geometric parameters and the measured temperature. Estimation results using a neural network show the enhanced effectiveness of multi-point surface temperature monitoring compared to one-point monitoring.

Behavior of Water Quality in Freshwater Lake of Tide Reclaimed Area Using SWMM and WASP5 Models (SWMM과 WASP5모형을 이용한 간척지 담수호의 수질거동 특성 조사)

  • 김선주;김성준;이석호;이준우
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.44 no.2
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    • pp.148-160
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    • 2002
  • Lake water quality assessment information is useful to anyone involved in lake management, from lakeshore owners to lake associations. 11 provides lake water quality, which can improve how to manage lake resources and how to measure current conditions. It also provides a knowledge base that can be used to protect and restore lakes. SWMM was applied to simulate the discharge and pollutant loads from Boryeong watershed, and WASP5 was applied to analyze the changes of water quality in Boryeong freshwater lake. In each model, the most suitable parameters were calculated through sensitive analysis and some parameters used default data. Simulated in SWMM and measured discharge showed the accuracy of 88.6%. T-N and T-P exceeds the criteria in the simulation of water quality in Boryeong freshwater lake, and control of pollutant loads in the main stream showed the most effective way. Integrated water quality management system was developed to give convenience in the operation of SWMM and WASP5 and data acquisition.

A Tentative Methodology for Quality Control of Trackbed Fills Using Field and Laboratory P-Wave Measurements

  • Park, Chul-Soo;Park, In-Beom;Kim, Eun-Jung;Mok, Young-Jin
    • International Journal of Railway
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    • v.1 no.2
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    • pp.64-71
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    • 2008
  • The quality of track-bed fills of railways has been controlled by field measurements of density $({\gamma}_d)$ and the results of plate-load tests. The control measures are compatible with the design procedures whose design parameter is $k_{30}$ for both ordinary-speed railways and high-speed railways. However, one of fatal flaws of the design procedures that there are no simple laboratory measurement procedures for the design parameters ($k_{30}$ or, $E_{v2}$ and $E_{v2}/E_{v1}$) in design stage. A new quality control procedure, in parallel with the advent of the new design procedure, is being proposed. This procedure is based upon P-wave velocity involving consistently the evaluation of design parameters in design stage and the field measurements during construction. The Key concept of the procedure is that the target value for field compaction control is the P-wave velocity determined at OMC using modified compaction test, and direct-arrival method is used for the field measurements during construction. The procedure was verified at a test site and the p-wave velocity turned out to be an excellent control measure. The specifications for the control also include field compaction water content of OMC${\pm}$2% as well as the p-wave velocity.

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An Economic-Statistical Design of Moving Average Control Charts

  • Yu, Fong-Jung;Chin, Hsiang;Huang, Hsiao Wei
    • International Journal of Quality Innovation
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    • v.7 no.3
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    • pp.107-115
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    • 2006
  • Control charts are important tools of statistical quality control. In 1956, Duncan first proposed the economic design of $\bar{x}-control$ charts to control normal process means and insure that the economic design control chart actually has a lower cost, compared with a Shewhart control chart. An moving average (MA) control chart is more effective than a Shewhart control chart in detecting small process shifts and is considered by some to be simpler to implement than the CUSUM. An economic design of MA control chart has also been proposed in 2005. The weaknesses to only the economic design are poor statistics because it dose not consider type I or type II errors and average time to signal when selecting design parameters for control chart. This paper provides a construction of an economic-statistical model to determine the optimal parameters of an MA control chart to improve economic design. A numerical example is employed to demonstrate the model's working and its sensitivity analysis is also provided.

The Effects of Imprecise Measurement on the Economic Asymmetric $\bar{X}$ and S Control Charts

  • Yang, Su-Fen
    • International Journal of Quality Innovation
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    • v.3 no.2
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    • pp.46-56
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    • 2002
  • The presence of imprecise measurement may seriously affect the efficiency of process control and production cost. A cost model is derived to determine the design parameters of the economic asymmetric $\bar{X}$ and S control charts including measurement errors. The effects of imprecise measurement on the performance of the economic asymmetric $\bar{X}$ and S control charts and production cost are examined for the case where the process mean and process standard deviation may change. Application of the proposed control charts is demonstrated through an example. Numerical examples illustrate the effects of imprecise measurement on the design parameters of the proposed control charts. It shows that the imprecision measurement may seriously affrct the ability of the proposed control charts to detect process disturbances quickly, change the sampling frequency, and increase the production cost compared to the control charts excluding measurement errors.

A study on Water Quality Changes in Distribution System (Factor analysis of deterioration of water quality & Modelling of free chlorine) (상수도 배관망에서의 수질변화에 관한 연구 (수질악화의 영향인자 분석과 잔류염소 모델링))

  • Lee, Hyun Dong;Chung, Won Sik;Moon, Sook Mi
    • Journal of Korean Society of Water and Wastewater
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    • v.11 no.3
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    • pp.59-66
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    • 1997
  • Although it produces well-treated water in water treatment plant, water quality at the tap can be changed depending on the state of pipes. It is because water quality deteriorates as plant water passes through pipeline networks. Therefore, the improvement of not only water treatment technology but also O & M of water pipelines is required to supply good water to consumers. The purpose of the study was to obtain the basic data of control technology for water quality in pipes through investigating water quality in distribution system. We selected 11 sampling sites and investigated water quality from plant to endpoint of distribution system. we also simulated decreasing tendency of free chlorine through pipeline network. As the result of water quality test, all parameters were below allowable levels, but some parameters had the possibility of being over levels. So there must be more work to set up proper countermeasure for violable parameters.

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Economic Design of a Moving Average Control Chart with Multiple Assignable Causes when Two Failures Occur

  • Cben, Yun-Shiow;Yu, Fong-Jung
    • International Journal of Quality Innovation
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    • v.2 no.1
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    • pp.69-86
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    • 2001
  • The economic design of control charts has been researched for over four decades since Duncan proposed the concept in 1956. Few studies, however, have focused attention on the economic design of a moving average (MA) control chart. An MA control chart is more effective than the Shewhart chart in detecting small process shifts [9]. This paper provides an economic model for determining the optimal parameters of an MA control chart with multiple assignable causes and two failures in the production process. These parameters consist of the sample size, the spread of the control limit and the sampling interval. A numerical example is shown and the sensitivity analysis shows that the magnitude of shift, rate of occurrence of assignable causes and increasing cost when the process is out of control have a more significant effect on the loss cost, meaning that one should more carefully estimate these values when conducting an economic analysis.

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A Study on Prediction of Optimized Penetration Using the Neural Network and Empirical models (신경회로망과 수학적 방정식을 이용한 최적의 용입깊이 예측에 관한 연구)

  • 전광석
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.8 no.5
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    • pp.70-75
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    • 1999
  • Adaptive control in the robotic GMA(Gas Metal Arc) welding is employed to monitor the information about weld characteristics and process paramters as well as modification of those parameters to hold weld quality within the acceptable limits. Typical characteristics are the bead geometry composition micrrostructure appearance and process parameters which govern the quality of the final weld. The main objectives of this paper are to realize the mapping characteristicso f penetration through the learning. After learning the neural network can predict the pene-traition desired from the learning mapping characteristic. The design parameters of the neural network estimator(the number of hidden layers and the number of nodes in a layer) were chosen from an error analysis. partial-penetration single-pass bead-on-plate welds were fabricated in 12mm mild steel plates in order to verify the performance of the neural network estimator. The experimental results show that the proposed neural network estimator can predict the penetration with reasonable accuracy and gurarantee the uniform weld quality.

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