• Title/Summary/Keyword: different methods

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Comparison of observational posture evaluation methods based on perceived discomfort (지각불편도를 이용한 관찰적 작업자세 평가 기법의 비교)

  • Lee, In-Seok;Jeong, Min-Geun;Choe, Gyeong-Im
    • Journal of the Ergonomics Society of Korea
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    • v.22 no.1
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    • pp.43-56
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    • 2003
  • Observational methods such as OWAS, RULA, and REBA have been widely used to identify posture-related risks of musculoskeletal disorders in industry, since they are useful and efficient in evaluating postural stresses. However. there are few studies comparing the methods and providing guidelines for selecting and using the methods. They have been developed based on different backgrounds and with different application areas. Each method has its own characteristics. which must be considered in selecting and using them. In this study. 17 male subjects evaluated 42 different working postures that frequently assumed in the automobile assembly line using a psychophysical method. The postures were then evaluated by different observational methods. The results of the observational methods were compared with psychophysically evaluated stresses. The observational methods resulted in different values of stresses for certain postures. For some postures showing high values of perceived discomfort. the observational methods showed different values of stresses. These results showed that the observational methods should be used differently according to application area and they have some weak points to be improved.

Evaluation criterion for different methods of multiple-attribute group decision making with interval-valued intuitionistic fuzzy information

  • Qiu, Junda;Li, Lei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.7
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    • pp.3128-3149
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    • 2018
  • A number of effective methods for multiple-attribute group decision making (MAGDM) with interval-valued intuitionistic fuzzy numbers (IVIFNs) have been proposed in recent years. However, the different methods frequently yield different, even sometimes contradictory, results for the same problem. In this paper a novel criterion to determine the advantages and disadvantages of different methods is proposed. First, the decision-making process is divided into three parts: translation of experts' preferences, aggregation of experts' opinions, and comparison of the alternatives. Experts' preferences aggregation is considered the core step, and the quality of the collective matrix is considered the most important evaluation index for the aggregation methods. Then, methods to calculate the similarity measure, correlation, correlation coefficient, and energy of the intuitionistic fuzzy matrices are proposed, which are employed to evaluate the collective matrix. Thus, the optimal method can be selected by comparing the collective matrices when all the methods yield different results. Finally, a novel approach for aggregating experts' preferences with IVIFN is presented. In this approach, experts' preferences are mapped as points into two-dimensional planes, with the plant growth simulation algorithm (PGSA) being employed to calculate the optimal rally points, which are inversely mapped to IVIFNs to establish the collective matrix. In the study, four different methods are used to address one example problem to illustrate the feasibility and effectiveness of the proposed approach.

Effect of Ultrasonic Treatment on Physicochemical Properties and Palatability of Cooked Chicken Meat (초음파 처리가 가열 계육의 이화학적 성질 및 기호성에 미치는 영향)

  • 박충균;박성하;전덕수;김현대;문윤희;정인철
    • Food Science of Animal Resources
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    • v.21 no.2
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    • pp.126-132
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    • 2001
  • This study was carried out to investigate the effect of ultrasonic treatment on physicochemical and sensory properties of cooked chicken meat. Moisture content of ultrasonic treated breast meat was higher than that of control, fat content of control of breast and leg meat were higher than that of ultrasonic treatment, and protein of control of breast meat was higher than that of ultrasonic treatment. Hunters L(lightness)-and a(redness)-value were not different between cooking methods, L-value of breast meat and a-value of leg meat were higher without regard to cooking method. Hunterb (yellowness)-value was not different among cooking chicken meats. Cooking yield was not different between cooking methods, pH of ultrasonic treated chicken meats were higher than that of control. Water holding capacity and salt soluble protein extractability of ultrasonic treated breast meat were greater than that of control. Water soluble protein extractability of ultrasonic treated leg meat was higher than that of control, and shear force value was not different between cooking methods. Hardness, cohesiveness and gumminess were not different between cooking methods and parts of muscle. Springiness of ultrasonic treated leg meat was greater than that of control and chewiness of breast meat was higher than that of leg meat. Aroma, texture, juiciness and overall acceptability were not different between cooking methods, taste of ultrasonic treated leg meat was higher than that of control. In addition, the sensory scores of parts of muscle were affected greater than that of cooking methods.

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Measuring Methods and Their Improvement of Formaldehyde Emission from Wood-Based Panels (목질제품의 포름알데히드방출량 측정방법과 개선방안)

  • Park Byung-Dae;Park Jong Young
    • Journal of the Korea Furniture Society
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    • v.15 no.2
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    • pp.1-17
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    • 2004
  • This paper attempted to review measuring methods of formaldehyde emission from wood-based panel products. Methods included for the discussion were desiccator methods, extraction method, and various chamber methods. First, the procedures and testing conditions of 24-hour desiccator method was critically reviewed, and an improvement of this method was proposed to meet international standards. Two different small chamber methods ($20\ell$ and $1m^3$ chamber methods) were also compared in terms of their advantages and disadvantages. In addition, the regulation levels of formaldehyde emission of wood-based composite panels were compared for different countries. The selection of a reference method of measuring formaldehyde emission of wood panel products should consider the ease of conducting test and cost required. Results should be exchangeable for different methods.

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Influence of Data Preprocessing

  • Zhu, Changming;Gao, Daqi
    • Journal of Computing Science and Engineering
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    • v.10 no.2
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    • pp.51-57
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    • 2016
  • In this paper, we research the influence of data preprocessing. We conclude that using different preprocessing methods leads to different classification performances. Moreover, not all data preprocessing methods are necessary, and a criterion is given to make sure which data preprocessing is necessary and which one is effective. Experiments on some real-world data sets validate that different data preprocessing methods result in different effects. Furthermore, experiments about some algorithms with different preprocessing methods also confirm that preprocessing has a great influence on the performance of a classifier.

Animal Model Versus Conventional Methods of Sire Evaluation in Sahiwal Cattle

  • Banik, S.;Gandhi, R.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.9
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    • pp.1225-1228
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    • 2006
  • A total of 1,367 first lactation records of daughters of 81 sires, having 5 or more progeny were used to evaluate sires by 3 different methods viz., least squares (LS), best linear unbiased prediction (BLUP) and derivative free restricted maximum likelihood (DFREML) method. The highest and lowest overall average breeding value of sires for first lactation 305 days or less milk yield was obtained by BLUP (1,520.72 kg) and LS method (1,502.22 kg), respectively. The accuracy, efficiency and stability of different sire evaluation methods were compared to judge their effectiveness. The error variance of DFREML method was lowest ($191,112kg^2$) and its coefficient of determination of fitting the model was highest (33.39%) revealing that this method of sire evaluation was most efficient and accurate as compared to other methods. However, the BLUP method was most stable amongst all the methods having coefficient of variation (%) very near to unadjusted data (18.72% versus 19.89%). The higher rank correlations (0.7979 to 0.9568) between different sire evaluation methods indicated that there was higher degree of similarity of ranking sires by different methods ranging from about 80 to 96 percent. However, the DFREML method seemed to be the most effective sire evaluation method as compared to other methods for the present set of data.

CORRELATION STUDY OF THE MEASURED TUMBLE RATIOS USING THREE DIFFERENT METHODS: STEADY FLOW RIG; 2-DIMENSIONAL PIV; AND 3-DIMENSIONAL PTV WATER FLOW RIG

  • Kim, M.J.;Lee, S.H.;Kim, W.T.
    • International Journal of Automotive Technology
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    • v.7 no.4
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    • pp.441-448
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    • 2006
  • In-cylinder flows such as tumble and swirl play an important role on the engine combustion efficiencies and emission formations. The tumble flow, which is dominant in current high performance gasoline engines, is able to effect fuel consumptions and emissions under a partial load condition in addition to the volumetric efficiency under a wide open throttle condition. Therefore, it is important to optimize the tumble ratio of a gasoline engine for better fuel economy, lower emissions, and maximum volumetric efficiency. First step for optimizing a tumble ratio is to measure a tumble ratio accurately. For a tumble ratio measurement, many different methods have been developed and used such as steady flow rig, PIV, PTV, and LDV. However, it is not well known about the relations among the measured tumble ratios using different methods. The purpose of this research is to correlate the tumble ratios measured using three different methods and find out merits and demerits of each measurement method. In this research the tumble flow was measured, compared, and correlated using three different measurement methods at the same engine: steady flow rig; 2-dimensional PIV; and 3-dimensional PTV water flow rig.

Comparison of Different Methods for Line Impedance Estimation

  • Alemi, Payam;Seo, Bo-Hwan;Lee, Dong-Choon
    • Proceedings of the KIPE Conference
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    • 2010.07a
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    • pp.454-455
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    • 2010
  • This paper surveys recent works in line impedance estimation. Inverters used in distribution system are often connected to the grid through LCL filter. Different methods are investigated for estimating the line impedance. Advantages and disadvantages with brief summary for each method are presented. Simulation results for a specified grid are shown for two main different methods and the results are compared with estimation error.

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Numerical approaches for vibration response of annular and circular composite plates

  • Baltacioglu, Ali Kemal;Civalek, Omer
    • Steel and Composite Structures
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    • v.29 no.6
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    • pp.759-770
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    • 2018
  • In the present investigation, by using the two numerical methods, free vibration analysis of laminated annular and annular sector plates have been studied. In order to obtain the main equations two different shell theories such as Love's shell theory and first-order shear deformation theory (FSDT) have been used for modeling. After obtaining the fundamental equations in briefly, the methods of harmonic differential quadrature (HDQ) and discrete singular convolution (DSC) are used to solve the equation of motion. Accuracy, convergence and reliability of the present HDQ and DSC methods were tested by comparing the existing results obtained by different methods in the literature. The effects of some geometric and material properties of the plates are investigated via these two methods. The advantages and accuracy of the HDQ and DSC methods have also been examined with different grid numbers and shell theory. Some results for laminated annular plates and laminated circular plates were also been supplied.

Performance Evaluation of Different Factors According to ROI Coding Methods in JPEG2000

  • Kim, Ho-Yong;Shim, Jong-Chae;Seo, Yeong-Geon
    • Journal of Digital Contents Society
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    • v.7 no.3
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    • pp.183-191
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    • 2006
  • Currently, the preferred processing of a user-centered ROI(Region-of-Interest) or a specific region of image to transmission and decompression of a full image is needed in different applications, specifically mobile applications. Here, we have to study how different factors affect ROI coding methods. Therefore, an application can select an ROI coding method and several parameters suitable for the environments. The ROI coding methods used in the study are Maxshift and Implicit and the parameters are tile size, image size, code block size, ROI importance and the number of lowest resolution levels. This study shows the experimental results between the different parameters and the two ROI coding methods.

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