• Smart Structures and Systems
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• v.24 no.4
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• pp.475-490
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• 2019

The detection of structural damage without a priori information on the healthy state is challenging. In order to address the issue, the study presents a baseline-free approach to detect damage in beam structures based on an actual influence line. In particular, a multi-segment function-fitting calculation is developed to extract the actual deflection influence line (DIL) of a damaged beam from bridge responses due to a passing vehicle. An intact basis function based on the measurement position is introduced. The damage index is defined as the difference between the actual DIL and a constructed function related to the intact basis, and the damage location is indicated based on the local peak value of the damage index curve. The damage basis function is formulated by using the detected damage location. Based on the intact and damage basis functions, damage severity is quantified by fitting the actual DIL using the least-square calculation. Both numerical and experimental examples are provided to investigate the feasibility of the proposed method. The results indicate that the present baseline-free approach is effective in detecting the damage of beam structures.

• Proceedings of the Optical Society of Korea Conference
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• 1989.02a
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• pp.59-64
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• 1989

Raman vibrational Q0branch spectra of pure CO are measured by using the technique of quasicw inverse Raman spectroscopy utilizing a pulsed single-frequency laser source. This approach gives enhanced sensitivity compared to earlier work which employed CW lasers, allowing extension of that work to higher accuracy, higher J states, and higher pressure. Fitting laws with pertubation theory and modified energy gap(MEG) theory are described, and the line broadening and shifting coefficients of J=0 to 24 are determined with both fitting laws.

• Journal of Korea Multimedia Society
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• v.12 no.1
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• pp.50-57
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• 2009

This paper proposes a extraction of feature lines on a polygonal model using local implicit surface fitting technique. To extract feature lines on a polygonal model, the previous technique addressed to compute the curvature and their derivatives at mesh vertices via global implicit surface fitting. It needs a user-specified precision parameter for finding an accurate projection of the mesh vertices onto an approximating implicit surface and requires high-time consumption. But we use a local implicit surface fitting technique to estimate the local differential information near a vertex by means of an approximating surface. Feature vertices are easily detected as zero-crossings, and can then be connected along the direction of principal curvature. Our method, demonstrated on several large polygonal models, produces a good fit which leads to improved visualization.

• ETRI Journal
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• v.38 no.4
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• pp.776-786
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• 2016

The fairly recent standard of equipping mobile devices with advanced imaging sensors has opened the possibility of conveniently diagnosing skin conditions, anywhere, anytime. For this application, we attempted to estimate skin conditions from a skin image taken by a mobile handheld camera. To estimate the skin conditions, we specifically identified three skin features (pigmentation, pores, and roughness) that can be measured quantitatively from a skin image. The experimental data indicate that the existing thresholding methods are inappropriate for extracting the pigmentation and pore skin features. Thus, we propose a new line-fitting based thresholding method for skin feature detection. We thoroughly evaluated our proposed skin condition estimation method using our skin image database. The experimental results show that our proposed thresholding method can better determine the threshold leading to the most visually plausible detection, when compared to existing methods. We also confirmed that skin conditions can be feasibly estimated using a common mobile handheld camera (for example, a smartphone).

• Journal of Welding and Joining
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• v.14 no.5
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• pp.78-86
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• 1996

Vision sensor was used to track the weld line of the compressor case. The compressor case was fixed in jig equipped with the rotating system, and two torches having one degree of freedom was applied in automatic welding system. The radius of rotation for the compressor case is varying with each rotating angle, while, the angle velocity is constant Therefore, an algorithm to extract the feature of the compressor case for varying rotation angle is needed. To over come the avove difficulties, the curve fitting and composite curve were used. The experiment to verify the proposed algorithm showed desirable results for tracking the welding line of compressor case.

• Journal of the korean Society of Automotive Engineers
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• v.6 no.2
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• pp.39-46
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• 1984

There are various ringshaped automotive and machine parts and the study about the characteristics of ring are the important basis of the quality control and performance improvement of outer race of ball bearing, railwheel, ring gear, piston ring, and other ringshaped seals, etc. In this study, the effect of prestress which arise inevitably during the fitting of the ring shape parts and the effect of central line extension/contraction on the vibrational characteristics of ring are verified. Although many studies are made on the vibration of ring, the study about prestress and extension were rather scarce and rare. As a result of the study, a series of frequency formulas are derived. The result of this study can be utilized in the improvement of design as well as in the quality control during the fitting work.

• Proceedings of the Korean Nuclear Society Conference
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• 1999.10a
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• pp.351.1-351
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• 1999

• Journal of the Korean Society of Costume
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• v.58 no.1
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• pp.133-150
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• 2008

The purpose of this study was to recognize of the sizing system and analyze the fitting on formal pants of the on-line shopping mall for plus-sized women. To pursue this purpose, the investigation of the sizing system was focused on 22 online companies. The formal pants of 7 companies was selected among them. And actual sizes were compared with the guidance sizes of goods. For the assessment about the fitting on formal pants of 7 online companies, these came to make on to 16 obese women with 'A' body shaped and 'O' body shaped. A data analysis used the SPSS 14.0 statistics program. To verify the difference, this study used the variance analysis and Duncan's test for the postmortem verification. The result was as follows. 1. All of 22 companies were using the symbol such as 88, 99, 100 and 110 in the present condition of sizing system. The information about products size was presenting the products size not to be the body size. the guidance sizes of products were different from actual sizes of 7 companies to be assorted. Therefore, the guidance sizes of goods could not accomplish the facility. 2. According to the fitting-tests by the sensory assessment, the obese women with 'A' body shaped, did the dissatisfaction at the items of the hip circumference, abdominal region, crotch deep and pants length. The obese women with 'O' body shaped, did the dissatisfaction at the the items of crotch deep and pants length.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.4
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• pp.719-730
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• 2001

The purpose of this study is to develop the basic patterns of adult womens brassiere therewith, provide for some basic data useful to the brassiere manufacturing which are both functional and fitting. For this purpose, 220 adults women(aged between 20 and 59) were sampled to be measured for their body sizes and tested for their brassiere wearing. The collected data were statistically processed using the SAS 6.12 for Means, Standard Deviation, etc. The results of this study can be summarized as follows; 1. In order to develop the basic patterns of adult womens brassieres, 75A size was selected out of 12 size combination(3 women per 75A size) and then, their brassiere fitting was tested. As a result, the fronts of the basic patterns were found to have such problems as undone front center, poor levelling of upper cups bottom line or lower cups top line, poor shape of upper cups outside top line and shoulder strip position. On the other hand, n the rear side of the basic patterns, the central part of the wing was slightly lifted, while the wing width and straps interval did not befit the full-cup brassiere. The result of this first brassiere fitting test showed that the functionality and aesthetics of the basic pattern brassieres were more or less satisfactory, and thus, the problems were address for the second test. In the second test, the aesthetics, breast-shaping effect and functionality of the basic pattern brassieres were much improved. 2. The basic patterns of adult womens brassieres were characterized by a round cup wired as well as a full cup embracing the entire breasts. Each basic pattern which consisted of upper and lower cups was shaped \"straight(-)\". The basic sizes adopted at the first design stage (see fig. 1-2) was 75A of which was designed as upper foundation basic pattern. At the second stage, the upper body foundation pattern were used to design lower cup, upper cup, front panel and wing in their order.(see fig. 3-5, fig. 8)5, fig. 8)

• Journal of Astronomy and Space Sciences
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• v.30 no.4
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• pp.307-314
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• 2013

Infrared optical systems are operated at low temperature and vacuum (LT-V) condition, whereas the assembly and alignment are performed at room temperature and non-vacuum (RT-NV) condition. The differences in temperature and pressure between assembly/alignment environments and operation environment change the physical characteristics of optical and opto-mechanical parts (e.g., thickness, height, length, curvature, and refractive index), and the resultant optical performance changes accordingly. In this study, using input relay optics (IO), among the components of the Immersion GRating INfrared Spectrograph (IGRINS) which is an infrared spectrograph, a simulation based on the physical information of this optical system and an actual experiment were performed; and optical performances in the RT-NV, RT-V, and LT-V environments were predicted with an accuracy of $0.014{\pm}0.007{\lambda}$ rms WFE, by developing an adaptive fitting line. The developed adaptive fitting line can quantitatively control assembly and alignment processes below ${\lambda}/70$ rms WFE. Therefore, it is expected that the subsequent processes of assembly, alignment, and performance analysis could not be repeated.