• Journal of the Korea Safety Management & Science
• /
• v.10 no.1
• /
• pp.191-195
• /
• 2008

The present study contributes reviewing and suggesting various models for measurement system analysis (MSA). Measurement errors consist of accuracy, linearity, stability, part precision, repeatability and reproducibility (R&R). First, the major content presents split-plot design, and the combination method of crossed and nested design for obtaining gage R&R. Second, we propose $\bar{x}-s$ variable control chart for calculating the gage R&R and number of distinct category. Lastly, investigating the determination of gage performance curve which establishes the control specification propagating calibration uncertainties and measurement errors is described.

• International Journal of Aerospace System Engineering
• /
• v.2 no.1
• /
• pp.24-30
• /
• 2015

In helicopter bearingless rotor design, the flexbeam is the key component of rotor system, which plays an importantrole in the blade flapping, lead-lag movement, torsion, and load transfer. Flexbeam must have the minimum torsion stiffness with enough tension strength. In this paper, we first investigated the torsion stiffness of different cross section configurations of the flexbeam through some simple experiments. Then we analyzed a rotor's dynamical characteristics with finite element method and got the rotor's fan plot. After that, we studied the relationship between the frequency changes with the spanwise distribution of mass and stiffness in bearingless rotor. Finally, we analyzed the influence of the flexbeam on dynamical characteristics of the bearingless rotor system, and completed the design of this type of rotor flexbeam.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.45 no.6
• /
• pp.83-95
• /
• 2003

In this study, a new concept in a paddy consolidation project is introduced in that curved parallel terracing with contour-lined layout is adopted in sloping areas instead of conventional rectangular terracing. The contoured layout reduces earth-moving considerably compared to rectangular methods in consolidation projects. The objective of the paper is to develop a combinatorial optimization model using the network theory for the design of contour-lined plots which minimizes the volume of earth moving. The results showed that as the length of short side of plot is longer or the land slope is steeper, the volume of earth moving for land leveling increases. The developed optimization model is applied for three consolidated districts and the resulting optimal earth moving is compared with the volume of earth from the conventional method. The shorter is the minimum length of short side of a polt with increases the number of plots, the less is the volume of earth. As the minimum length of short side is 20 m for efficient field works by farm machinery, the volume of earth moving of optimal plot is less by 21.0∼27.1 % than that of the conventional consolidated plots.

• Journal of Industrial Technology
• /
• v.14
• /
• pp.127-140
• /
• 1994

This study is concerned with the accuracy and the patterns when different methods was used in interpolation task. Although 3 methods employed the same modality for input (visual) and for output (manual responding), they differed in central processing, which method 1 is relatively more tendency of verbal processing, method 2 is realtively more tendency of spatial processing and method 3 needed a number of switching code (verbal/spatial) performing task. Split-plot design was adopted, which whole plot consisted of methods (3), orientations (horizon, vertical), base-line sizes (300, 500, 700 pixels) and split plot consisted of target locations (1-99). The results showed the anchor effect and the range effect. Method 2, method 3 and method 1 that order was better accuracy. ANOVA showed that the accuracy was significantly influenced by the method, the location of target, and its interactions ($method{\times}location$, $size{\times}location$). Analysis of error data, response time and frequency of under, just, over estimate indicated that a systematic error pattern was made in task and methods changed not only the performance but also the pattern. The results provided support for the importance of the multiple resources theory in accounting for S-C-R compatibility and task performance. They are discussed in terms of multiple resources theory and guidelines for system design is suggested by the S-C-R compatibility.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.12 no.4
• /
• pp.422-429
• /
• 2000

Plate and shell heat exchanger(P&SHE) is widely applied as evaporators or condensers in the refrigeration and air conditioning systems for their high efficiency and compactness. In order to set up the database for the design of the P&SHE, heat transfer and pressure drop characteristics for single phase flow of water in a plate & shell heat exchanger are experimentally investigated in this study. Single phase heat transfer coefficients were measured for turbulent water flow in a plate and shell heat exchangers by Wilson plot method. The shell side heat transfer resistance was varied and the overall heat transfer coefficients were measured. The single-phase heat transfer coefficients in a plate side were obtained by Wilson plot method. Single-phase heat transfer correlations based on projected heat transfer area and friction factor correlations have been proposed for single phase flow in a plate and shell heat exchanger.

• Journal of Plant Biology
• /
• v.20 no.2
• /
• pp.103-107
• /
• 1977

Two sample varieties of Yushin and Jinheung were used for the experiment in low-level wetty paddy field which was arranged with PVC pipe underdrainage of 6m in distance and 60cm, 90cm, and 120cm in depth and control, using sprit plot design with three replications. On the yield of brown rice, Yushin was increased by 24.8% in the 90cm plot and Jinheung by 16.7% in the 120cm plot, respectively, over the control. The ratio of matured grains of these two varieties was increased significantly by the underdrainage and the number of grains per head of Yushin was also increased in drained plots. Otherwise, the underdrainage enhanced the plant height in the early growth of rice plant and further increased the culm height and panicle length. It seemed that these results might enhance the light-receiving effciency in the latter growth of rice plant and bring about the effect fo increased yields by the underdrainage.

• Journal of Korean Society for Quality Management
• /
• v.25 no.4
• /
• pp.88-98
• /
• 1997

For quality improvement, it is important to reduce variations of the quality characteristic. That can be achieved by the a, pp.ication of parameter design methodology to make the performance of the quality characteristic robust over the variety of noise conditions. Taguchi has used the signal-to-noise ratios for that purpose. For the static target characteristic and the dynamic characteristic problem, we propose a reasonable generalized SN ratio and p-value plot for identifying dispersion factors. The orginal idea of the p-value plot in from the gamma-plot in Lunani, Nair & Wasserman(1995). The graphic advantage of the p-value polt for identifying dispersion factors is illustrated through constructed examples.

• Journal of the Korean Statistical Society
• /
• v.32 no.3
• /
• pp.235-244
• /
• 2003

In unreplicated factorial or fractional factorial experiments, the presence of one or more outliers can seriously affect the analysis of variance. Using the normal plot of t residuals to identify outliers in factorial or fractional factorial is an easy method to find these dubious points. In some cases, the t residuals form the identical pairs. One can not tell from the plot which is doubtful. This phenomenon occurs for all minimal designs of resolution IV, which fits the model containing all main effects and some two-factor interactions, whether it is orthogonal or not. In these kinds of models, when we drop one point or two points (not foldover pair) from the fraction, the phenomenon of identical pairs of t residuals may still occur. In this paper, the theoretical background of the phenomenon and its sequences will be investigated in detail.

• Asian-Australasian Journal of Animal Sciences
• /
• v.12 no.6
• /
• pp.891-894
• /
• 1999

A field experiment was conducted with Calliandra calothyrsus of fifteen provenances to evaluate the variation in the condensed tannin content of fresh leaves. Plants were raised in a nursery for three months and planted in the field. Experimental design was line planting of double hedgerows (3 m long plot, 1/2 meter interval, 45 plants in each plot) with 5 replicates. Plants were lopped every 5 months and samples (10 different plants within a plot; 4 newly flushed leaves, 4 partially expanded leaves and 4 mature full expanded leaves from each of 10 trees in a plot) were collected and were put on ice before transfer to the laboratory. Proanthocyanidine was extracted in aqueous acetone, and total extractable proanthcyanidine (TEPA) and total proanthocyanidine (TOPA) were measured. In addition, proximate analyses were made of different provenances. Crude protein contents varied from 19.74% to 16.45%; in vitro organic matter digestibility ranged from 36.09% to 23.32%. TEPA content ranged from 11.22 to 16.01 (measured as absorbance at $550nm,\;g^{-1}$ DM) and TOPA from 24.57 to 31.72 (measured as absorbance at $550nm,\;g^{-1}$ DM) TEPA and TOPA had a positive correlation, whereas crude protein content of Calliandra was negatively correlated with TEPA and TOPA. Provenances, such as Georgesville (Belize), local, Coban (Guatemala), Patulul (Guatemala), Bombana (Mexico) can be selected on the basis of nutritive value of fodder.

• Korean Journal of Soil Science and Fertilizer
• /
• v.51 no.2
• /
• pp.79-89
• /
• 2018

Subsurface drip irrigation (SDI) system is considered one of the most effective methods for water application. A 2-year field study was conducted to investigate the effect of SDI systems with various dripline spacing (0.7 or 1.4 m) and position (under furrow or ridge) on soybean (Glycine max L.) production at a sandy-loam soil in Miryang, South Korea. For 2016-2017, average grain yield in SDI irrigated plots, $3.16Mg\;ha^{-1}$, was statistically greater than rainfed irrigated plot ($2.63Mg\;ha^{-1}$). Soybean grain yield averaged $3.25Mg\;ha^{-1}$ for the 0.7 m dripline spacing and $3.07Mg\;ha^{-1}$ for the 1.4 m spacing for the two-year period compared to a rainfed irrigated average of $2.63Mg\;ha^{-1}$ for the same period. Soybean treated with SDI system had significantly greater values of normalized difference vegetation index and stomatal conductance, indicating that soybean plants in SDI plots had greater photosynthetic and stomatal activity due to the higher water availability in soil. Irrigation water use efficiency (IWUE) was greatest in the plot of 0.7 m spacing installed under ridge position than any other plot across growing season. Average soil water content in plots with 0.7 m dripline spacing was $0.21m^3\;m^{-3}$ at 5 cm depth layer, which was 45% greater compared to the plots with 1.4 m spacing, even though the gross irrigation amounts were greater in 1.4 m spacing plots. It is concluded that wide dripline spacing (1.4 m) is probably the more economical installation design for SDI system compared to 0.7 m spacing in this study soil because the initial cost for dripline may be reduced with wide spacing design, even though the IWUE is greater in the plot of 0.7 m dripline spacing.