• Journal of the Korean Solar Energy Society
• /
• v.30 no.6
• /
• pp.59-65
• /
• 2010

Analysis on turbulence intensity profile depending on wind speed is an important process to set up design condition of wind turbine in terms of fatigue load. This paper tests goodness of fit of turbulence intensity empirical equations suggested by the IEC 61400 Standards with Jejudo Gimnyeong met-tower measurement, which is erected at a seashore. Therefore sea breeze and land breeze coexist. Sea breeze case showed apparent increasing trend of turbulence intensity in a high wind speed regime due to increase of sea surface roughness. However, neither inland wind turbine standard IEC 61400-1 nor offshore wind turbine standard IEC 61400-3 fit such a trend adequately. On the other hand, the modified empirical equation of turbulence intensity of IEC 61400-3 derived from Germany FINO1 application study by considering turbulence intensity behavior in a high wind speed regime showed good agreement with the measurement. Therefore, we can reconfirm and conclude that IEC 61400-3 Ed.1 legislated in 2009 needs to be modified.

• The Journal of Industrial Distribution & Business
• /
• v.3 no.2
• /
• pp.5-16
• /
• 2012

Purpose - Distribution channels cannot function without cooperation. While evidence suggests channel power plays a fundamental role in fostering successful manufacturer-dealer channel cooperation in Western countries distribution systems, little is known empirically as to how dealers' possession of non-mediated powers influence SME manufacturers' cooperation in Asian developing countries. Research design, data, methodology - Drawing upon the extant distribution channels literatures; this study conceptualizes a model and examines the effects of dealer's non-mediated powers on manufacturing SME firms, as well as the mediating influence of trust, relationship satisfaction and commitment. A survey of 400 manufacturing SMEs in Taiwan empirically supports the proposed hypothesis. Results - The model is acceptable in terms of overall goodness of fit. Acceptable model fit are indicated by χ²/(df): 2.35, GFI≧.90; RMSEA values≦ .08; IFI, TLI and CFI values≧.90. Our results indicate that, GFI (0.910), IFI (0.937), TLI (0.903), CFI (0.936), and RMSEA (0.079) and therefore, achieved the suggested thresholds. Conclusions - The results of this study have some managerial implications for managers in the dealer's firms. The overall implication from the findings is that managers can utilize expert, referent and traditional legitimate powers to attain channel cooperation with manufacturing SMEs in addition to garnering their trust, relationship satisfaction and commitment.

• The Journal of Asian Finance, Economics and Business
• /
• v.8 no.5
• /
• pp.1139-1145
• /
• 2021

This study is aimed at developing a measurement instrument for the superior product development program of Deli Serdang cassava, Indonesia. This research population is the target population of Deli Serdang Micro, Small and Medium-sized Enterprises (MSMEs) which produces cassava. The sample was randomly selected and consisted of 300 MSMEs. The study method is research and development with confirmatory factor analysis using Amos software. The data collection technique was a questionnaire. Study results used the maximum likelihood method which showed that the validity and reliability instruments met the ideal loading factor value > 0.5 and a significance value of p (0.000). The model built also meets the fit criteria based on the Goodness of Fit Model Standard. All instruments are presented to build and measure the superior cassava product development program by Deli Serdang MSMEs. This superior product development program comprises (1) economic contribution (with a loading factor value of 0.76) (2) social aspects (with a loading factor value of 0.76) (3) cultural aspects (with a loading factor value of 0.99) and (4) institutional (with a loading factor value of 0.87). This result means that all instruments have proven construct validity.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.21 no.4
• /
• pp.108-117
• /
• 1979

In order to obtain the basic data for design of water structures which can be contributed to the planning of water use. Best fitted distribution function and the equations for the probable minimum flow were derived to the annual minimum flow of five subwatersheds along Geum River basin. The result were analyzed and summarized as follows. 1. Type III extremal distribution was considered as a best fit one among some other distributions such as exponential and two parameter lognormal distribution by $x^2$-goodness of fit test. 2. The minimum flow are analyzed by Type III extremal distribution which contains a shape parameter $\lambda$, a location parameter ${\beta}$ and a minimum drought $\gamma$. If a minimum drought $\gamma=0$, equations for the probable minimum flow, $D_T$, were derived as $D_T={\beta}e^{\lambda}1^{y'}$, with two parameters and as $D_T=\gamma+(\^{\beta}-\gamma)e^{{\lambda}y'}$ with three parameters in case of a minimum drought ${\gamma}>0$ respectively. 3. Probable minimum flow following the return periods for each stations were also obtained by above mentioned equations. Frequency curves for each station are drawn in the text. 4. Mathematical equation with three parameters is more suitable one than that of two parameters if much difference exist between the maximum and the minimum value among observed data.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.33 no.5
• /
• pp.1731-1740
• /
• 2013

The design life and durability of the bridges are strongly affected by the Gross Vehicle Weight(GVW) of heavyweight trucks. The Weigh-In-Motion(WIM) systems are typically used to collect information on truck total weight and speed. The statistical analysis of the GVW measured using High Speed WIM systems showed that most of heavy vehicles were from Vehicle Type 7, 10, and 12. The analysis was also carried out to determine goodness of fit with theoretical probability distributions. The normal distribution was shown to best describe the overall distribution of GVW. The top 10% of the GVW appeared to best fit by the Weibull 3 probability distribution.

• Child Health Nursing Research
• /
• v.24 no.3
• /
• pp.287-297
• /
• 2018

Purpose: This study aimed to identify variables influencing the psychosocial adjustment of North Korean adolescent refugees in order to establish a structural equation model and design an intervention strategy to improve psychosocial adjustment. Methods: The subjects included 290 North Korean adolescent refugees aged 16~24 years who were enrolled in alternative schools or regional adaptation centers. They were surveyed using a structured questionnaire. Results: The goodness of fit measures of the model were as follows: $x^2=131.20$ (p<.001), GFI=.93, CFI=.91, TLI=.86, RMSEA=.08, and SRMR=.07. The results estimated from the structural equation model indicated a good fit of data to the hypothesized model, which proposed that stress and emotional intelligence are associated with psychosocial adjustment. The major variables influencing psychosocial adjustment were stress, emotional intelligence, which was a significant direct effect, whereas attitude of parenting showed an indirect effect on psychosocial adjustment through emotional intelligence. These variables account for 50.0% of psychosocial adjustment. Conclusion: It is necessary to develop a program and intervention plan that can enhance emotional intelligence and thereby relieve the stress of North Korean adolescent refugees. The program should also include parenting education so that parents have positive attitude of parenting.

• International Journal of Reliability and Applications
• /
• v.3 no.1
• /
• pp.1-16
• /
• 2002

In reliability engineering, the bathtub-shaped hazard rates play an important role in survival analysis and many other applications as well. For the bathtub-shaped, initially the hazard rate decreases from a relatively high value due to manufacturing defects or infant mortality to a relatively stable middle useful life value and then slowly increases with the onset of old age or wear out. In this paper, we present a new two-parameter lifetime distribution function, called the Loglog distribution, with Vtub-shaped hazard rate function. We illustrate the usefulness of the new Vtub-shaped hazard rate function by evaluating the reliability of several helicopter parts based on the data obtained in the maintenance malfunction information reporting system database collected from October 1995 to September 1999. We develop the S-Plus add-in software tool, called Reliability and Safety Assessment (RSA), to calculate reliability measures include mean time to failure, mean residual function, and confidence Intervals of the two helicopter critical parts. We use the mean squared error to compare relative goodness of fit test of the distribution models include normal, lognormal, and Weibull within the two data sets. This research indicates that the result of the new Vtub-shaped hazard rate function is worth the extra function-complexity for a better relative fit. More application in broader validation of this conclusion is needed using other data sets for reliability modeling in a general industrial setting.

• Geomechanics and Engineering
• /
• v.35 no.5
• /
• pp.499-509
• /
• 2023

The objective of this study is to perform outlier analysis to obtain the distribution of groundwater levels through the best model. The groundwater levels are measured in 10, 25 and 30 piezometers in Seoul, Daejeon and Suncheon in South Korea. Fifty-eight empirical distribution functions were applied to determine a suitable fit for the measured groundwater levels. The best fitted models based on the measured values are determined as the Generalized Pareto distribution, the Johnson SB distribution and the Normal distribution for Seoul, Daejeon and Suncheon, respectively; the reliability is estimated through the Anderson-Darling method. In this study, to choose the appropriate confidence interval, the relationship between the amount of outlier data and the confidence level is demonstrated, and then the 95% is selected at a reasonable confidence level. The best model shows a smaller error ratio than the GEV while the Mahalanobis distance and outlier labelling methods results are compared and validated. The outlier labelling and Mahalanobis distance based on median shown higher validated error ratios compared to their mean equivalent suggesting, the methods sensitivity to data structure.

• Journal of Environmental Science International
• /
• v.14 no.12
• /
• pp.1203-1209
• /
• 2005

Basic dyes, Rhodamine 6G(R6G), Rhodamine B(RB), and Methylene Blue(MB), dissolved in water were used to investigate single-component adsorption affinity to the pearl layer fractionated according to the size. Unfractionated pearl layers were also used as adsorbents for the R6G and RB. The Langmuir and the Redlich-Peterson(RP) models were used to fit the adsorption data, and the goodness of fit was examined by using determination coefficient($R^2$) and standard deviation(SSE). The 3-parameter RP model was found to be better in describing the dye adsorption data than the 2 parameter Langmuir model, as can be expected from the number of parameters involved in the model. The adsorption affinity to the fractionated pearl layer was higher than that to the unfractionated layer The affinity order to the fractionated Conchiolin layer was found to be R6G > MB > RB. Furthermore, the dye adsorption capacity of the various types of pearl layer was found to be in the order, the fractionated pearl > powdered pearl > unfractionated pearl, exhibiting different adsorption isotherms according to the types of layer used in the study.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.36 no.1
• /
• pp.63-72
• /
• 1994

The objective of the study is to develop weather generators for daily rainfall and small pan evaporation and to test the applicability with recorded data. Daily rainfall forecasting model(DRFM) was developed that uses a first order Markov chain to describe rainfall seque- nces and applies an incomplete Gamma function to predict the amount of precipitation. Daily evaporation forecasting model(DEFM) that adopts a normal distribution function to generate the evaporation for dry and wet days was also formulated. DRFM and DEFM were tested with twenty year weather data from eleven stations using Chi-square and Kolmogorov and Smirnov goodness of fit tests. The test results showed that the generated sequences of rainfall occurrence, amount of rainfall, and pan evaporation were statistically fit to recorded data from eleven, seven, and seven stations at the 5% level of significance. Generated rainfall data from DRFM were very close in frequency distri- bution patterns to records for stations all over the country. Pan evaporation for rainy days generated were less accurate than that for dry days. And the proposed models may be used as tools to provide many mathematical models with long-term daily rainfall and small pan evaporation data. An example is an irrigation scheduling model, which will be further detailed in the paper.