• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.9C
• /
• pp.882-888
• /
• 2006

Multiuser detection can significantly increase system capacity and improve service quality compared with the existing matched filter. In this paper, we introduce an method which efficiently calculates the maximum likelihood (ML) metric based on the gradient search (GS). The ML detection needs user powers as well as their spreading codes. A method is also proposed that allows us to detect data bits with the estimation of user powers when they are unknown. Computer simulation shows that the proposed method can nearly achieve the same performance as the GS with perfectly hewn user powers.

• The Journal of Korean Association of Computer Education
• /
• v.11 no.4
• /
• pp.85-93
• /
• 2008

This paper proposes a method for generating low-level geometric models with retaining salient features during decimation. Our method employs feature extraction technique for extracting feature lines defined via curvature derivatives on the model (we divide features into ridges and valleys). We add the extraction method to simplification technique (Feature Quadric Error Metric) for making coarse model with features. This paper clearly shows that experimental results have better quality and smaller geometric error than previous methods.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.4 no.3
• /
• pp.292-299
• /
• 2004

For Web System composed of a variety of hardware, software and network system, there is a wide difference in price, function and capacity. In addition, it is important to select the most suitable system when web system is constructed as the claim of high-quality web service from user has increased. Data of bench-marking is usually employed when the system is selected. Evaluation with the result of bench-marking, however, is not easy at web situation composed of a variety of systems. In this paper, first integrated bench-marking of hardware, software and network system metric were determined, and the plan to effectively compare and evaluate the result of bench-marking by using fuzzy set were offered.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.7 no.1
• /
• pp.22-31
• /
• 2008

The operating window method is a novel approach in quality improvement. But it has not received deserved attention in academic research. If a critical factor for competing failure modes can be identified, the probability of failure can be reduced by widening the operating window of this factor. Traditional SN ratio for the operating window advocated by Taguchi has a critical shortcoming, which has been derived under the assumption that failure rates are determined by the operating window factor only. A new metric for robustness is given for the operating window method, which has relaxed the restrictive assumption of Taguchi's SN ratio. And procedures for determining optimal conditions based on the new metric is presented. The effectiveness of the proposed approach over the traditional practice is tested with the aid of a wave soldering process.

• The KIPS Transactions:PartD
• /
• v.9D no.5
• /
• pp.897-902
• /
• 2002

Because of rapid evolution of software technique, numerous software professionals have been concerned with component based development methodologies. However, it is hard to find out a systematic technique for the selection of COTS (Commercial Off The Shelf) component in consumer position. Up to date, the major of component quality evaluation is object-oriented metric based evaluation methodology. But this paper present four step process and evaluation criteria based on MCDM (Multiple Criteria Decision Making) technique for optimal COTS component selection in consumer position. We considered funtionality, efficiency, usability based on IS0/IEC 9126 for Quality measurement and executed practical analysis about commercial EJB component in internet. This paper show that the proposed selection technique is applicable to optimal COTS component selection.

• The KIPS Transactions:PartD
• /
• v.10D no.5
• /
• pp.821-828
• /
• 2003

Package software should have the feature that enables purchasers to discriminate a product suitable for them among a number of software belonging to the similar kind of product. Purchaser's ability to choose a package software depends on whether they can judge that a package software conforms to the relevant standard through an objective quality test process and method or not. There are the standards that can be applicable to the quality evaluation of package software, such as and . This study developed a system with which purchasers can effectively select a package software suitable for their needs, building quality test process for package software and developing test metric and application method.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2004.05a
• /
• pp.1003-1008
• /
• 2004

In our life, we have used many digital appliances. They helped us to improve the quality of lift but sometimes gave us unsatisfactory result because they produce specific noise. Especially a vacuum cleaner produces a great deal of noise that is very annoying. So we need to study what sound metrics affect human sensibility. In this paper, we will study sound quality index for vacuum cleaner. The subjective evaluation of vacuum cleaner sound can be indicated to objective parameters by sound metrics of psychoacoustics. The artificial neural network can estimate the nonlinear characteristics of relation between subjective evaluation and sound metrics. We applied the artificial neural network to the development of sound quality index for vacuum sound.

• Proceedings of the IEEK Conference
• /
• summer
• /
• pp.128-132
• /
• 2004

In this paper, we propose a new image quality assessment scheme considering the human visual perception characteristics. A subjective quality assessment is obtained by the response of the receptive field in the primary visual cortex and a human's eye can't focus on all of the visual range in a moment. Take advantage of two facts above, we apply Gabor wavelet transform, which is well fit the receptive field in the cortex, to divided constant sized subblocks. Then a local distortion of the subblocks and a global distortion for the entire image are calculated in order. The proposed method has been evaluated using video test sequences provided by the Video Quality Experts Group (VQEG). The experimental results show that good correlation with human perception is obtained using the proposed metric, which is what we called GPSNR.

• The KIPS Transactions:PartD
• /
• v.11D no.3
• /
• pp.659-670
• /
• 2004

It is possible to implement high quality system which coincided with embedded system purchaser's requirements by quality test. The concrete quality test system applicable within our country for embedded software was not constructed yet. Recently, various embedded systems are developed, but they have many problems such as recall by defect. In this paper, we developed evaluation modules and quality test fables which can implement duality test based on ISO/IEC 12119 for embedded software evaluation.

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