• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.628-634
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• 2003

Rumbling sound is one of the most important interior sound of a passenger cu. The conventional rumbling noise research was focused on the reduction of the A-weighted sound pressure level. However A-weighted sound pressure level can not give the whole story about the rumbling sound of a passenger car. In this paper, we employed sound metric which is the subjective parameter used in psycoacoustics. According to recent research results, the relation between sound metrics and subjective evaluation is very complex and has nonlinear characteristics. In order to estimate this nonlinear relationship, artificial neural network th[ ory has been applied to derivation of sound quality index fur rumbling sound of a passenger car.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1224-1227
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• 2009

When evaluating the quality of images and displays, it is important to combine the characteristics as perceived by the human visual system and measured by equipment using subjective and objective methods, respectively. In the case of objective methods, the quality of a display is measured using colorimetric or radiometric devices according to existing standards covering the color temperature, gamut size, gamma characteristic, and device characterization. Meanwhile, subjective methods assess the quality of an image using the human visual system based on a comparison with a reference or counterpart using such metrics as the sharpness, noise, contrast, saturation, and color accuracy. Objective and subjective methods are usually used together in comparison, as ultimately it is observers watching images on a display. In addition to existing objective methods, a new image quality metric is also introduced as regards the JPEG compression ratio that is reflected in the relationship between the gamut size and the color fidelity in CIELAB color space.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.05
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• pp.215-220
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• 1996

Experimental set-up for the characterization of Shape Memory Alloys springs which are applicacable to endoscope has been implemented. Fundamental properties of SMA springs were measured by iso-thermal test iso-metric test, iso-tonic test and the relationship between stress and strain, temperature and generated force, displacement and temperature could be characterized experimentally. The implemented experimental set-up and characterization method can be exploited for the design of SMA springs and evaluation of actuators used in endoscope.

• Journal of the Semiconductor & Display Technology
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• v.20 no.2
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• pp.137-140
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• 2021

High dynamic range (HDR) technology has been drawing attention in the field of imaging and consumer entertainment. As tools for capturing and creating HDR contents, encoding, and transmission evolve to support HDR formats, various display capabilities are being developed and increased. Hence, there is need for remapping native HDR imagery for display on lower quality legacy standard dynamic range (SDR) displays. This operation is referred to as tone mapping. In this paper, we present a sectional tone mapping method by Lenzen, and expand upon a tone mapping approach to improve temporal stability while maintaining picture quality. Compared to the existing block-based sectional tone mapping, our method uses the edge awareness-based tone mapping. We estimate the performance of the objective metric on temporal flickering. The experimental result shows that the algorithm maintains a smoother relationship between the output luminance values, and this reveals success in reducing halos and improving temporal stability with adopted edge aware filtering.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.6
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• pp.780-787
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• 2005

Many researches and validations for the complexity metrics of the object-oriented systems have been studied. Most of them are aimed for the measurement of the partial aspects of the systems, for example, the coupling between objects, the complexity of inheritance structures, the cohesion of methods, and so on. But the software practitioners want to measure the complexity of overall system, not partial. We studied the complexity of the overall structures of object-oriented systems by analyzing the class diagram of UML. The class diagram is composed of classes and their relations. There are three kinds of relations, association, generalization, and aggregation, which are making the structure of object-oriented systems to be difficult to understand. We proposed a heuristic metric to measure the complexity of object-oriented systems by putting together the three kinds of the relations. Tn analyze the complexity of the structure of a object-oriented system for the maintainability of the system, we measured the degree of understandability of it, the reverse engineering time to draw a class diagram from the source codes, and the number of errors in the diagram. The results of this experiment shows that our proposed metric has a considerable relationship with the complexity of object-oriented systems. The metric will be helpful to the software developers for their designing tasks by evaluating the complexity of the structures of object-oriented systems and redesigning tasks , of them for the future maintainability.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.4
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• pp.351-357
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• 2008

An aerial multi-looking camera system equips itself with five separate cameras which enables acquiring one vertical image and four oblique images at the same time. This provides diverse information about the site compared to aerial photographs vertically. The geometric relationship of oblique cameras and a vertical camera can be modelled by 6 exterior orientation parameters. Once the relationship between the vertical camera and each oblique camera is determined, the exterior orientation parameters of the oblique images can be calculated by the exterior orientation parameters of the vertical image. In order to examine the exterior orientation of both a vertical camera and each oblique cameras in the multi-looking camera relatively, calibration targets were installed in a lab and 14 images were taken from three image stations by tilting and rotating a non-metric digital camera. The interior orientation parameters of the camera and the exterior orientation parameters of the images were estimated. The exterior orientation parameters of the oblique image with respect to the vertical image were calculated relatively by the exterior orientation parameters of the images and error propagation of the orientation angles and the position of the projection center was examined.

• Geotechnical Engineering
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• v.12 no.6
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• pp.139-152
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• 1996

In order to treat flow problems for unsaturated soils, it is necessary to obtain the soil-water characteristic curves which show nonlinear relationship between metric suction and volumetric water content. With two different pleasuring devices, measurements of the matric suction were taken for Jumoonjin sand, Hangang sand, and weathered granite soils with different fined. Experimental parameters which can describe experimental formulas for the soil-water characteristics were determined by using the data obtained from the experiment. Among experimental formulas of previous researchers, that of van Genuchten(1980) agreed well with the results of experiments. For weathered granite soils, the parameters increased with the increase of fine contents, Therefore, the soil-water characteristic for a weathered soil can be estimated by using Parameters corresponding to its fine contents.

• The KIPS Transactions:PartC
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• v.16C no.6
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• pp.717-724
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• 2009

The most important issue for successful deployment of IPTV service is the service quality. In this paper, we first choose critical quality metrics belonging to each layer of IPTV service transmission architecture and then analyze the relation between the quality parameters. For this purpose, we implement a test network that emulates the most practical environment in which IPTV service is provided and repeat measurements on the test network for the chosen metrics. Based on the analysis result, it is shown that packet losses have greater effect on the video quality of IPTV service comparing to delay and jitter.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.2
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• pp.907-923
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• 2020

For the severe haze situation in the Beijing-Tianjin-Hebei region, conventional fine particulate matter (PM2.5) concentration prediction methods based on pollutant data face problems such as incomplete data, which may lead to poor prediction performance. Therefore, this paper proposes a method of predicting the PM2.5 concentration based on image analysis technology that combines image data, which can reflect the original weather conditions, with currently popular machine learning methods. First, based on local parameter estimation, autoregressive (AR) model analysis and local estimation of the increase in image blur, we extract features from the weather images using an approach inspired by free energy and a no-reference robust metric model. Next, we compare the coefficient energy and contrast difference of each pixel in the AR model and then use the percentages to calculate the image sharpness to derive the overall mass fraction. Furthermore, the results are compared. The relationship between residual value and PM2.5 concentration is fitted by generalized Gauss distribution (GGD) model. Finally, nonlinear mapping is performed via the wavelet neural network (WNN) method to obtain the PM2.5 concentration. Experimental results obtained on real data show that the proposed method offers an improved prediction accuracy and lower root mean square error (RMSE).

• Journal of Nutrition and Health
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• v.38 no.1
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• pp.76-81
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• 2005

The effects of the amount of red pepper intake per a day on the capsaicin threshold, nutrient intake, and anthropo-metric measurements were investigated in 100 female students of university. Three 24-hour recalls were performed to estimate usual nutrient and red pepper intake of free-living participants. The solutions containing capsaicin at concentration of 0.05, 0.1, 0.2, 0.3, 0.4, 0.5ppm used for the evaluation of hot-taste detection threshold. Subjects were asked to recognize the burning sensation after tasting l0ml of each test solution in ascending order of capsaicin concentrations. Mean intake of red pepper was 4.6 g/d and the capsaicin threshold was 0.27 ppm. The detection threshold for capsaicin was correlated with the amount of pepper intake per a day. Red pepper intake was correlated with energy, protein, lipid, carbohydrate, Iron, vitamin A, vitamin B$_2$ niacin, and vitamin E intakes. However, it was not correlated with intake of calcium, vitamin B$_1$ or vitamin C. The red pepper intake was negatively correlated with fat mass and waist girth and the capsaicin threshold was also negatively correlated with pulse. In conclusion, red pepper intake was associated with nutrient intake and capsaicin threshold whereas it was negatively correlated with fat mass and waist girth.