• IE interfaces
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• v.15 no.4
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• pp.432-438
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• 2002

When the trailing edge and leading edge of an airfoil contour of high pressure compressor blades are measured, there exists a measurement error due to the size of the probe stylus ball diameter. In the paper an experimental study is provided to determine the optimum diameter of the probe stylus in inspecting the airfoil of the high pressure compressor blade. The measurement and analysis procedure suggested in this paper will be helpful to those who are involved in measuring and inspecting various types of blades.

• Journal of the Korean Society of Visualization
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• v.3 no.1
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• pp.26-35
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• 2005

The combination of ultrasound echo images with digital particle image velocimetry (DPIV) method has resulted in a two-dimensional, two-component velocity field measurement technique appropriate for opaque flow conditions including blood flow in clinical applications. Advanced PIV processing algorithms including an iterative scheme and window of offsetting were used to increase spatial resolution. The optimum concentration of the ultrasound contrast agent used for seeding was explored. Velocity validation tests in fully developed laminar pipe flow and pulsatile flow showed good agreement with both optical PIV measurements and the known analytic solution. These studies indicate that echo PIV is a promising technique for the non-invasive measurement of velocity profiles and shear stress.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.1
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• pp.69-77
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• 1998

Linear displacement accuracy is one of the most important factors that determine machine tool accuracy The laser interferometer has been usually recommended for the measurement of linear displacement accuracy. In this paper, microcomputer aided measurement and compensation system has been developed for the pitch error in a CNC machine tool. For accurate pitch error calculation. the analysis code for the pitch error has been also implemented according to the international standards (ISO). The PC based automatic compensation system for the pitch error is also implemented. A new algorithm for calculating optimum value for pitch error compensation is proposed, minimizing the deviation at each target points. The development system has been applied to a practical CNC maching center and the performance has been demonstrated.

• Journal of the Korean Home Economics Association
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• v.37 no.2
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• pp.113-126
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• 1999

In order to investigate the detergency effect of stained cotton and PET fabric, respectively, these fabrics stained with solid soils such as carbon black, liquid paraffin, and fat and examined the detergency effect in the optimum washing condition. The evaluation of washing efficiency of washed fabrics studied by using the surface reflectance measurement before and after washing treatment. The maximum detergency effect of stained cotton and PET fabric obtained in the mixed washing liquor-bleachig agen(ml)/concentrated washig agent(g/l). To obtain the excellent detergency effect, 2-step washing treatment, pre-washing by bleaching agent only and washing by concentrated detergent, is preferred. In comparing the detergency of polyester and cotton fabric, the detergency of stained polyester fabric superior than that of stained cotton fabric because of the difference of adhesive force between soil material and fabric in preparing soled stained fabric. In this study, we also studied the degree of fabric damage by the measurement of tensile strength change. From the results of the tensile strength measurement, the damage of washed fabric before and after washing treatment was nearly changed.

• Journal of the Korea Safety Management & Science
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• v.8 no.1
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• pp.43-52
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• 2006

The goal of this study is to investigate the ergonomic factors in designing or selecting the hand tool handle. Electromyogram (EMG) were measured for various wrist postures and handle sizes under two loading conditions. Anthropometric data were measured and the correlation with EMG measurement data were analyzed. Investigations of this study show that wrist posture should be neutral for minimum muscle tension and optimum handle size can be found by measuring the EMG measurement data. It show that hand width and EMG measurement data is greatly correlated also. This study can be a guide of designing or selecting a hand tool, but further study with large sample sizes and various groups is needed for making general conclusion.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.1
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• pp.5-10
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• 2011

The effect of sample handling condition on the rheological measurement of regenerated silk fibroin formic acid solution using parallel plate geometry was investigated. In case of loading method, the loading by pouring sample solution resulted in the best reproducibility of rheological measurement. Loading with spoon showed a high variance of viscosity value at low shear rate region ($0.01{\sim}1sec^{-1}$) while loading with syringe exhibited a low reproducibility of viscosity at high shear region ($1{\sim}100sec^{-1}$) with a disappearance of shear thinning phenomenon. It was revealed that the sample loading with small extra amount lead to the most reproducible result. The sample loading with the exact amount for the measuring plate resulted in a lack of reproducibility of high shear viscosity, while the loading with large extra volume produced a limited consistency of low shear viscosity. It was turned out that 3 min. of waiting time before measurement was the optimum condition for reliable result. When the waiting time was less than 1 min., the low shear viscosity was obtained with a lack of consistency. On the other hand, the sample solution started drying when the waiting time increased up to 5 min.

• Journal of Environmental Science International
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• v.19 no.6
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• pp.747-753
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• 2010

It follows in quality and sewage exclusion method of the investigation objective sector and the Combined Sewer Overflows which is suitable in regional characteristics and the confluence area against the rainfall initially a flow and the medulla and measurement - it analyzes the initial rainfall outflow possibility control plan which is suitable in the domestic actual condition and it proposes the monitor ring plan for the long-term flow and pollution load data accumulation. From the research which it sees the Infiltration water/Influent water and CSOs investigation it passes by the phase of hazard chain and Namwon right time 4 it does not hold reverse under selecting, Measurement it used the hazard automatic flow joint seal Sigma 910 machine and in case 15 minute interval of the I/I, it measured a flow at case 5, 15 minute standing of the CSOs. The water quality investigation for the water leakage investigation of the I/I and the sewage from the point which is identical with flow measurement during on-the-spot inspection duration against 6 items which include the BOD sampling and an analysis, when the rainfall analysis for CSOs fundamental investigation analyzed against 18 items which include the BOD sampling. Consequently, for the optimum interpretation invasion water / inflow water of the this investigation area day average the lowest flow - water quality assessment veterinarian optimum interpretation hazard average per day - lowest flow - it averages a medulla evaluation law department one lowest flow evaluation technique and it selects, it presentation collectively from here it gets, position result with base flow analysis of invasion water / inflow water.

• Journal of the Korean association of regional geographers
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• v.7 no.1
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• pp.35-50
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• 2001

Since remotely sensed images of coastal wetlands are very sensitive to spatial resolution, it is very important to select an optimum resolution for particular geographic phenomena needed to be represented. Scale is one of the most important factors in spatial analysis techniques, which is defined as a spatial and temporal interval for a measurement or observation and is determined by the spatial extent of study area or the measurement unit. In order to acquire the optimum scale for a particular subject (i.e., coastal wetlands), measuring and representing the characteristics of attribute information extracted from the remotely sensed images are required. This study aims to explore and analyze the scale effects of attribute information extracted from remotely sensed coastal wetlands images. Specifically, it is focused on identifying the effects of scale in response to spatial resolution changes and suggesting a methodology for exploring the optimum spatial resolution. The LANDSAT TM image of Sunchon Bay was classified by a supervised classification method, Six land cover types were classified and the Kappa index for this classification was 84.6%. In order to explore the effects of scale in the classification procedure, a set of images that have different spatial resolutions were created by a aggregation method. Coarser images were created with the original image by averaging the DN values of neighboring pixels. Sixteen images whose resolution range from 30 m to 480 m were generated and classified to obtain land cover information using the same training set applied to the initial classification. The values of Kappa index show a distinctive pattern according to the spatial resolution change. Up to 120m, the values of Kappa index changed little, but Kappa index decreased dramatically at the 150m. However, at the resolution of 240 m and 270m, the classification accuracy was increased. From this observation, the optimum resolution for the study area would be either at 240m or 270m with respect to the classification accuracy and the best quality of attribute information can be obtained from these resolutions. Procedures and methodologies developed from this study would be applied to similar kinds and be used as a methodology of identifying and defining an optimum spatial resolution for a given problem.

• The Journal of the Acoustical Society of Korea
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• v.18 no.6
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• pp.31-37
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• 1999

This paper describes the far-field estimation using the near-field measurement data. Measurement in far-field region gives us the acoustical characteristics of the source but in general measurement is made in near-field such as acoustic water tank or anechoic chamber, so far-field acoustical characteristics of the source should be predicted from near-field data. In this case, the number of measurement points in the near field which relates to the accuracy of the predicted field and the amount of data processing, should be optimized. Existing papers say that measurement points is proportional to kL and depends on geometry and directivity of the source. But they do not give us any definite criterion for the required number of measurement points. Boundary Collocation Method which is one of the far-field prediction methods, is analyzed based on Helmholtz integral equation and Green function and it has been found that the number of measurement points is optimized as 0.54kL which is about one half of the existing results.

• Journal of Korean Institute of Industrial Engineers
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• v.2 no.1
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• pp.61-78
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• 1976

The purpose of this study is to establish the horizontal and vertical working area which is dependent on measuring value of workers, body in order to make easy and stable working environments, and then to design the size of machines, tools and instruments in production factory because of making the practical production conditions which is the most suitable to human characteristics. But there is necessity that we have to review numeric value of measurement periodically because the size of workers' body is variable according to periodic and social circumstances. The establishment of standard working area after measurement enable us to make the best working conditions and we can design standard working table, optimum size of all machines and tools in production activity. Therefore, we can also acknowledge the importance of studying on human engineering because human engineering is necessary to reduction of fatigue in working, saving workers from industrial accidents, fail-safe system, improvement of productivity with increase in efficiency and etc. Finally, this study informs us that numeric value of measurement is larger than that of Japan, but not than that of America and Germany. So we can establish standard working area which is the most suitable for Korean inherence after measurement of detailed parts for workers' body.