• Journal of international Conference on Electrical Machines and Systems
• /
• v.3 no.3
• /
• pp.339-353
• /
• 2014

A straightforward method for optimal determining of a high frequency inductor's parasitic capacitance is presented. The proposed estimation method is based on measuring the inductor's impedance samples over a limited frequency range bordering on the resonance point considering k-dB deviation from the maximum impedance. An optimized solution to k could be obtained by minimizing the root mean squared error between the measured and the estimated impedance values. The model used to provide the estimations is a parallel RLC circuit valid at resonance frequency which will be transferred to the real model considering the mentioned interval of frequencies. A straightforward algorithm is suggested and programmed using MATLAB which does not require a wide knowledge of design parameters and could be implemented using a spectrum analyzer. The inputs are the measured impedance samples as a function of frequency along with the diameter of the conductors. The suggested algorithm practically provides the estimated parameters of a real inductance model at different frequencies, with or without design information. The suggested work is different from designing a high frequency inductor; it is rather concentration of determining the parameters of an available real inductor that could be easily done by a recipe provided to a technician.

• Journal of Korean Society for Geospatial Information Science
• /
• v.5 no.2 s.10
• /
• pp.65-75
• /
• 1997

Nowadays, digital map plays a role as a container of spatial database.'there have been many researches concerning the improvements of the digital map accuracy. From the user's viewpoint, however, the quality level of digital nap is as important as its accuracy, because fitness-for-use is considered the most important factor to the users. This study aims to find the methodology for determining the grade nか digital map. To accomplish this, we propose two major stages. First, weight factors of the layers are given according to the importance of the functions which must be considered in digital map generation. Scond, weight factors of the components to evaluate the accuracy of the digital map are presented By scoring the components and by summing the scores, the method for determining fitness-for-use is developed.

• Journal of Biosystems Engineering
• /
• v.41 no.3
• /
• pp.170-176
• /
• 2016

Purpose: This study aimed to improve the method for determining the position of the center of gravity for agricultural tractors. Methods: The proposed method uses trigonometric functions and coordinate transformation. Data were measured according to the ISO 789-6 test procedures for the center of gravity of agricultural tractors. The height calculated using the proposed method was compared with that determined from an AutoCAD drawing. To find the center of gravity of the tractor, the algorithm for finding the intersection of the two lines was used. Results: The vertical height from the ground to the center of gravity is 682.06 mm. The vertical coordinates obtained from the calculation and the drawing were the same. Conclusions: The developed method uses trigonometric and polar coordinate transformation. The method was compared and verified with the AutoCAD drawing results. The results indicate that users can apply this developed method instead of the plotting method which is an inconvenient and time-consuming. Further, users can program Microsoft Excel to easily determine the vertical coordinate. In addition, researchers will propose this method to the ISO as a standard method for determining the center of gravity in accordance with ISO 789-6.

• Journal of Welding and Joining
• /
• v.15 no.6
• /
• pp.41-48
• /
• 1997

For analyzing the characteristics of arc welding processes, an algorithm is necessary to determine the metal transfer mode, arc stability and weld quality. In this study, the weight of spatter during welding was selected for determining the arc stability, which is very relevant to the occurrence of spatter. Weld spatter occurs mainly at the moment when the short circuit is formed and also when it is broken causing the arc to restrike. Based on this fact, the arc stability can be determined by finding the suitable parameters of welding current and arc voltage which influence the weight of spatter. Through various welding experiments, the peak current, the arcing time, the short circuit time, the current and its slope at the start of short circuit were found mainly to influence the weight of spatter. For the convenient usage, an index was proposed by combining all these parameters. It was found that the index is very effective for determining the arc stability.

• Journal of the Korea Safety Management & Science
• /
• v.9 no.1
• /
• pp.77-84
• /
• 2007

This study was planned to investigate what the main factor of the regulation compliance of inspection on harmful machine, instrument and equipment by industrial safety and health act is. This study subject was composed of three groups as employers, employees of manufacturing and using the harmful machine and safety inspectors. Manufacturing workplace were 236 places, using workplace were 201 places and the safety inspectors were 100 people. The study subject was sampled by stratified random sampling considering the type of harmful Machine. Data for analysis is collected from each sample using interview with structured questionnaires. Compliance is measured by 2, 3, and 4 point scale composed by 8 sub items such as general perception, understanding, clearness, necessity, relevancy, implementation, penalty, and general compliance of the regulation. The level of 8 items of employer's compliance are not differentiated among three groups. The determining factors for inspection observance of the workplace using the harmful Machine were understanding, penalty and cognized compliance. The determining factors for inspection observance of the workplace manufacturing the harmful Machine were understanding and object conformity. These results show that the strategy to adapt the regulated group to inspection regulation will be the elevation of understanding for regulation first of all.

• Journal of the Korean Data and Information Science Society
• /
• v.24 no.1
• /
• pp.125-133
• /
• 2013

In this paper, penalized binary logistic regression models are employed as statistical models for determining the discharge of 668 patients with a chief complaint of dyspnea based on 11 blood tests results. Specifically, the ridge model based on $L^2$ penalty and the Lasso model based on $L^1$ penalty are considered in this paper. In the comparison of prediction accuracy, our models are compared with the logistic regression models with all 11 explanatory variables and the selected variables by variable selection method. The results show that the prediction accuracy of the ridge logistic regression model is the best among 4 models based on 10-fold cross-validation.

• Journal of Korean Society of Forest Science
• /
• v.59 no.1
• /
• pp.63-66
• /
• 1983

Sectional equilibrium moisture contents of Larix leptolepis and Populus euramericana I-476 were determined, their correlations and significances were investigated. Among the ovendry moisture contents. electric moisture meter determining values and the estimative values through chemical equilibria formula, there were significant correlations, 1-5% level, at whole sections in Larix leptolepis. However, in Populus euramericana there was only significant correlation between ovendry moisture content values and electric moisture meter determining values.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.24 no.11
• /
• pp.23-29
• /
• 2010

The principal factor determining an optimum design method for cathodic protection is finding the protection current for preventing the corrosion of existing, already laid pipe. Some factors currently used to test designs include the sizes and lengths of pipes, soil resistivity, and the coating damage rate. We believe this method and current formulae are not optimum due to the uncertainty of determining the coating damage rate and the corrosion protection current's density. This paper analyzes the amount of protection current obtained by performing a temporary current test using data describing existing laid pipe. We then propose determining the corrosion protection current by using the temporary current test after modifying the formula. In addition, we suggest a way to choose optimized cathodic protection and the process of design by executing the design and taking account of such factors as a site condition of 34km-long non-protected water supply pipe lines (stages I and II) in ${\bigcirc}{\bigcirc}$ region, climate, interferences, and durability.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.5 no.3
• /
• pp.115-122
• /
• 2001

Bridge load rating calculations provide a basis for determining the load carrying capacity of bridges. Load rating requires engineering judgement in determining a rating value that is applicable to maintaining the safe use of the bridge and arriving at posting and permit decisions. Load testing is an effective means in calculating the rating value of bridge. In Korea, load carrying capacity of bridge is modified by response modification factor that is determined from comparisons of measured values and analysis results. This paper presents the development of a method for determining the response the modification factor, using traffic loads. The proposed method is based on the results of computer simulations of traffic action effects. The simulation program generates random traffic actions for defined traffic conditions and determines the frequency distribution of maximum traffic action effects. A comparison between the proposed method and the present method shows good agreement in estimating the modified load carrying capacity of bridges.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.13 no.5
• /
• pp.51-58
• /
• 2010

This study was done to recommend a method for conserving the habitat of Amblyotropis verna grown naturally in campus of the Kyungpook National University at Daegu city. Vegetation characteristics and morphological characteristics of each individual were analyzed for the condition of the population at the growing season from May to June in 2010. Totally 11 vegetation data were collected and analyzed, and one vegetation community including Amblyotropis verna (Amblyotropis verna-Zoysia japonica community) was found. We found that the growing condition was not good with severe stamping and disturbance. The location-determining method by PCoA analysis showed the physical texture in soil was a critical factor determining the spatial distribution of the Amblyotropis verna-Zoysia japonica community. And the analysis of morphological characteristics found that light condition and soil hardness were the main ecological factor determining the size and form of each individual. Finally, this study recommend that minimizing impacts by human stamping and artificial disturbance and reducing the water stress were the best ways for the conservation of Amblyotropis verna habitats.