• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.3
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• pp.348-356
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• 2014

The existing effective path-length model of ITU-R has some drawbacks: The prediction error is quite large compared to domestic measurement data and it is an empirical model in which the physical characteristics of rain cells are not considered. In this paper, a theoretical model for effective path-length using the rain-cell concept was proposed and its validity was verified using the measurement data. To analyze the statistical characteristics of rain cell parameters, the weather-radar data(CAPPI) measured by Korea Meterological Administration were analyzed and the correction factor was properly introduced to fit the Chollian beacon measurement data of ETRI(Electronics and Telecommunications Research Institute). To verify the proposed effective path-length model, it was compared with the Mugunghwa No. 5 beacon data measured in Chungnam National University with the support of ADD(Agency for Defense Development). It was confirmed that the prediction results of the proposed model are in good agreement with the measurement data.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.2
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• pp.37-42
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• 2016

This paper proposes a method to develop a high-precision dimension measurement system using a linear variable differential transformer sensor. The Dimension targets for measurement is carbon material vanes of key element in the rotating parts within vehicle circulating pump. Data acquisition system for dimension measurement is designed using the NI Compact RIO. And the program applying the dimension measurement algorithm is built using NI LabVIEW. The dimension measuring program is composed of a FPGA program, Real Time program and Host program. The method of the experiment compares master vane with target vane for measure the length of the carbon material vane. The experimental results confirmed the usefulness of the accuracy within ${\pm}4um$.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.6
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• pp.448-455
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• 2003

A system design technique of automatic thickness measurement and defect inspection system, which measures the thickness of the ALC(Autoclaved Lightweight Concrete) block and inspects the defect on a realtime basis is proposed. The image processing system was established with a CCD camera, an image grabber, and a personal computer without using assembled measurement equipment. The image obtained by this system was analyzed by a devised algorithm, specially designed for the enhanced measurement accuracy. For the realization of the proposed algorithm, the preprocessing method that can be applied to overcome uneven lighting environment, an enhanced edge decision method using 8 edge-pairs with irregular and rough surface, the unit length decision method in uneven condition with rocking objects, and the curvature calibration method of camera using a constructed grid are developed. The experimental results, show that the required measurement accuracy specification is sufficiently satisfied using our proposed method.

• ETRI Journal
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• v.31 no.1
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• pp.68-70
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• 2009

In this letter, a parametric analysis of the Fresnel-field antenna measurement method is performed for a square aperture. As a result, the optimum number of Fresnel fields for one far-field point is guided as $M_{opt}=N_{opt}=D^2/{\lambda}R+5$, where D is the antenna diameter, ${\lambda}$ is the wavelength, and R is the distance between the source antenna and the antenna under test. For the aperture size 5 ${\leq}$ $L_x/{\lambda}$ ${\leq}$ 20, the tolerable distances for gain errors of 0.5 dB and 0.2 dB can be guided as $R_{0.5\;dB}$ ${\approx}$ $1.2Lx/{\lambda}$ and $R_{0.2\;dB}$ ${\approx}$ $2.0L_x/{\lambda}$, where $L_x$ is the lateral length of the square aperture. The tolerable distances for 20 ${\leq}$ $L_x/{\lambda}$ ${\leq}$ 200 are also proposed. This measurement guideline can be fully utilized when performing the Fresnel-field antenna measurement method.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.6
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• pp.34-40
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• 2004

This paper presents studies on curvature radius measurement using the laser interferometer. It is a general practice to measure to $10^{-10}$m in length with the recent improvement and innovations in measurement technology and the processor used. The measurement methods can generally be categorized as these two: the contactual method and non-contactual method; and in this study, we will find ways to lower the cost for a CMM, or a coordinate measurement machine, and try to find an alternative. Furthermore, we will discuss some of the ways to improve the non-contactual measurement methods-optical interferometer method and the optical triangulation method. We will measure an object using a laser distance measuring device and Set the Point-contact result with the ball-bearing type and line-contact result with the bearing type, to decide on which probe type will be used.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.6
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• pp.454-458
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• 2009

The technology of virtual environments has been developed with better-quality appearance on a computer display in mind, but without consideration for objects' precise measurements in physical units. With the increased application of computer graphics in a variety of areas, there is a need for precise measurement functionality in addition to visualization. This paper describes the definition of physical properties using measurement units for X3D based virtual objects, to provide their precise physical information in virtual environments. To this end, we have included the physical property node in the X3D specification. The physical measurement units, such as length, mass, time, temperature, etc., are based on SI units (International System of Units).

• Journal of Fashion Business
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• v.7 no.4
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• pp.78-92
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• 2003

The upper-body characteristics of the right-handed and the left-handed are examined and compared through 1-dimensional measurement and 2-dimensional measurement. The results were as follows: 1. According to 1-dimensional measurement results, the clearest differences were seen in girth items rather than height or length items. In particular, hand girth, lower arm girth, and upper arm girth were bigger on the left side in the left-handed group and the right side in the right-handed group. This is thought to be relevant to the arm muscles frequently used. 2. According to 2-dimensional measurement results, significant differences appeared in the females of the left-handed group: shoulder point among width items. In the right-handed group, some differences of significance were shown in females (shoulder point, rear armpit point, and B.P. point among width items) and males (front neck point among extreme vertical distance items). In summary, the body type characteristics of the left-handed and the right-handed reveal great differences in the items related to arm length and arm girth. In other words, the sleeve and shoulder patterns production based on the right-handed don't rightly reflect the somatotype characteristics of the left-handed. In addition, in the cases of athletes, laborers, and the disabled who frequently use particular muscles or parts of the body, this sort of research in the patterns is consistently needed in order to reflect the size differences in girth items in upper body.

• Journal of the Ergonomics Society of Korea
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• v.18 no.2
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• pp.11-24
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• 1999

The purpose of this study was to obtain the basic data for sound wear design. The objects' of this study were 331 women's university students. The eight items were the shoulder length, shoulder slope, height, weight, chest girth, neck girth, back length, and back shoulder width. The shoulder length and slopes were measured, compared with the right, the left, and other items. The results were as follows; The difference between the right and left shoulder length did not nearly appear. The mean of the right shoulder slopes was $21.3^{\circ}$, and that of the left was $21.9^{\circ}$. According to increase of the age, the right and left shoulder slope tends to be higher. The maximum distribution was $20.7^{\circ}$. According to increase of the age, the maximum distribution tends to be higher. The left compared with the right shoulder length, the right shoulder length of 90.3% objects' was longer than that of the left. The right and left shoulder length of 4.2% objects' were same. The left shoulder length of 5.4% objects' was longer than that of the right. The left compared with the right shoulder slopes, the right shoulder slopes of 12.7% objects' were higher than those of the left. The both size of 20.5% objects' were equal. The left slopes of 66.8% objects' was higher than those of the right.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.6
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• pp.1116-1122
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• 2008

Since conventional methods for measuring stride length(distance) are many weaknesses, optical methods have been developed to measure stride length(distance) of human pedestrians. IR(Infrared) elements and Power LED(Light Emitting Diode) with two types of lens were used to correlate detected light intensity with stride length(distance). The suggested methods in this study are simple, convenient, and cost effective. The results can be used to analyze walking patterns of normal and disabled men, and to monitor the recovering processes of the disabled patients.

• The Research Journal of the Costume Culture
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• v.17 no.5
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• pp.866-877
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• 2009

The purpose of this study was to develop the dimension of hand pattern-making for Korean glove. The glove pattern-making has difficult problem in combination of anthropometric and engineering aspects. In addition, existing dimension data are not enough for glove pattern-making. Therefore, to develop the dimension for glove this study comprehensive list of candidate hand data was reviewed and the manufacturers(career over the 15 years) were interviewed on the method of glove. The result of comparing between the structures in hand and existing glove pattern, there draw deduction from follows. Pattern-making for glove need size of hand length, thumb length, index finger length, middle finger length, ring finger length, hand circumference, thumb-ring finger circumference and maximum hand thickness.