• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.15 no.6
• /
• pp.475-484
• /
• 1990

This paper proposes a method for the implementation of a power line communication equipment using power line synchronization in a direct-sequence spread spectrum communication system. In order to implement a network using a power line as a transmission channel we have investigated the utilization of direct-sequence speread spctrum which gives such advantages as robustness against narrow-band interference and noise, and realization of multiple access. In a power line, however, complexity of synchronization makes it difficult to realize a multiple access and cost down and system simplification. The proposed technique of power line synchronization makes it possible to get cost down and system size small, and the realization of multiple communication can be achieved by the addition of address setting circuit.

• Journal of KIISE:Computing Practices and Letters
• /
• v.15 no.1
• /
• pp.57-61
• /
• 2009

To increase the efficiency of mining process and derive accurate spatio-temporal patterns, continuous values of attributes should be discretized prior to mining process. In this paper, we propose a discretization method which improves the mining efficiency by reducing the data size without losing the correlations in the data. The proposed method first s original trajectories into approximations using line simplification and then groups them into similar clusters. Our experiments show that the proposed approach improves the mining efficiency as well as extracts more intuitive patterns compared to existing discretization methods.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2012.05a
• /
• pp.449-450
• /
• 2012

오늘날 컴퓨터와 정보통신 기술에 의해 생성된 디지털 맵(map)은 다양한 분야에서 응용 활용되고 있다. 이에 디지털 맵 제작 기술의 발전과 함께 선형 단순화(line simplification) 기법에 대한 연구가 활발하게 진행되고 있다. 이에 본 논문은 라인의 형상을 최대한 보존하기 위하여 최소영역오차(minimum area error, MAE) 구간을 이용한 혼합형 선형 단순화 기법을 제안한다. 기존의 선형 단순화 기법과의 비교 실험을 통하여, 제안하는 기법의 성능이 우수함을 확인하였다.

• Journal of the Korean Society for Precision Engineering
• /
• v.23 no.3 s.180
• /
• pp.132-138
• /
• 2006

With a great requirement of innovation caused by severe competition current companies are encouraged to improve bottleneck areas in production procedure. Specially a chassis line in which assembly processes are mainly carried out manually has the large potential to be automated. The putting of spare tire in trunk in chassis line is still dominated by free dropping method. Through that, parts in trunk such as luggage room lamp, jack and so on were damaged and the complaint of assembler in the next process was occurred due to physical strength. To eliminate these, tile robot system was in this paper developed to place spare tire on the mounting hole in trunk. The movement of robot was synchronized with the velocity of chassis hanger. With this automated system the productivity of the chassis line was increased from the benefits such as simplification of the system using only robot without the mechanically synchronized transport, inserting spare tire into the right position with robot, reduction of damaged parts and production of various type of car.

• Journal of Information Processing Systems
• /
• v.1 no.1 s.1
• /
• pp.9-13
• /
• 2005

Computer security has become a critical issue with the rapid development of business and other transaction systems over the Internet. The application of artificial intelligence, machine learning and data mining techniques to intrusion detection systems has been increasing recently. But most research is focused on improving the classification performance of a classifier. Selecting important features from input data leads to simplification of the problem, and faster and more accurate detection rates. Thus selecting important features is an important issue in intrusion detection. Another issue in intrusion detection is that most of the intrusion detection systems are performed by off-line and it is not a suitable method for a real-time intrusion detection system. In this paper, we develop the real-time intrusion detection system, which combines an on-line feature extraction method with the Least Squares Support Vector Machine classifier. Applying the proposed system to KDD CUP 99 data, experimental results show that it has a remarkable feature extraction and classification performance compared to existing off-line intrusion detection systems.

• Ecology and Resilient Infrastructure
• /
• v.8 no.4
• /
• pp.266-272
• /
• 2021

Water friendly space refers to a place designated to plan and manage spaces for residents Water friendly activities. Efficient management of river Water friendly parks requires automated GIS data and DB construction of the water friendly facilities. Object-based classification using drone images or aerial images is attracting attention as an efficient means to acquire 3D spatial information in the country. To remove the miscellaneous image included in the extracted outline, a linear simplification of the outline is required, and it is difficult to apply manually, so various automation methods have been developed to overcome this, and among them, the most widely studied and utilized is the linear simplification method. In this study, the suitability of linear simplification algorithms such as Douglas-Peucker, Visvalingam-Whyatt, and Bend-simplify algorithms for the geometric shape of hydrophilic facilities was determined.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.30 no.5 s.153
• /
• pp.722-732
• /
• 2006

The pattern making of the tight-fitting collars which often used in diving suits, dance wear, or cycle wear has not been fully established. To develop tight-fitting collar pattern directly from 3D images from the representative somatotypes, dressforms developed by Jaeun Jung were used. The 3D scan data of the four male dressforms were obtained using Exyma-1200. Triangle Simplification and the Runge-Kutta method were applied to reduce the 3D scan data points and to make the segmented triangular patches in a plane from 3D data. As results, apparent differences between the tight-fitting collar patterns obtained from the 3D scan data and the ordinary 2D collar patterns were found around the center back line. The curvatures of the center back line were higher in all types of the tight-fitting collar than in the ordinary collar pattern. Relative differences in the shape of collar lines among four representative Korean men were reported. To fit the curved shape of the back neckline, 1.8 cm should be reduced from the upper neckline in average. We suggested the direct pattern making method for the 2D tight-fitting collar patterns considering the 3D shape of various types of men's dressform.

• Spatial Information Research
• /
• v.19 no.1
• /
• pp.73-82
• /
• 2011

Recently, demand for the use of cadastral map is increasing in both public and private area. To use cadastral map in web or mobile environment, construction of the multi-representation database(MRDB) that is the compressed into multiple scale from the original map data is recommended. In this study, the map generalization methodology for the cadastral map by applying overlay with topographic map and polygon generalization technique is suggested. This process is composed of three steps, re-constructing the network data of topographic map, polygon merging of parcel lines according to network degree, and applying line simplification techniques. Proposed methodologies are applied to the cadastral map in Suwon area. The result map was generalized into 1:5,000, 1:20,000, 1:100,000 scale, and data compression ratio was shown in 15% 8% 1% level respectively.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.7 no.1
• /
• pp.39-51
• /
• 2004

This study aims to suggest new algorithm, named as Simoo, in order to improve spatial conflicts and vector displacement between linear features in generalization of the linear features. Main principles of Simoo algorithm is adoption of simplification and smoothening methods. Tolerance conditions used in Simoo are perpendicular length, external angle, and average vertex length. Main characteristics of Simoo are the application of scale, cartographic refinement, minimization of logical errors, and maintenance of geographical properties. The Simoo was applied through comparison to existing Douglas-Peucker algorithm. Resultantly, maintenance ratios of line such as coastal line and stream network were over 97% in both algorithms. The elimination ratio of vertex points may be more effective in Douglas-Peucker than in Simoo. Spatial conflicts between linear features may be more minimized in Simoo. The curvature and smoothening of lines become decreased in scale in application of Simoo. Finally, Simoo algorithm may be more effective than Douglas-Peucker for cartographic generalization.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.33 no.3
• /
• pp.77-92
• /
• 2008

Commonality strategy is a popular design practice in designing a product line as it enables the firm cost saving and simplification in design, manufacturing, and distribution processes. However the issue of commonality has been mostly analyzed from a profit maximizing firm's perspective and, to our knowledge, there is no literature that deals with the issue from a different perspective. in this paper, we consider the issue of commonality strategy from a social welfare maximization perspective, and argue that commonality strategy used in designing of public goods can bring certain benefits not just for a firm but also for consumers, i.e., for society as a whole. While we assume certain cost saving in production process due to economies of scale under commonality strategy, we conceptualize two different effects of commonality strategy, utility effect due to cost saving and weighted-averaging effect, and show how these two effects interplay to determine the design of common attribute and desirability of commonality strategy. We also discuss how the implementation of commonality strategy differs under different objectives of a product line designer : social welfare and firm's profit maximization.