• Journal of Advanced Marine Engineering and Technology
• /
• v.28 no.4
• /
• pp.611-617
• /
• 2004

Pixel classification is one of basic image processing issues. The general characteristics of the pixels belonging to various classes are discussed and the radical principles of pixel classification are given. At the same time. a pixel classification scheme based on image direction measure is proposed. As a typical application instance of pixel classification, an adaptive multi-level median filter is presented. An image can be classified into two types of areas by using the direction information measure, that is. smooth area and edge area. Single direction multi-level median filter is used in smooth area. and multi-direction multi-level median filter is taken in the other type of area. What's more. an adaptive mechanism is proposed to adjust the type of the filters and the size of filter window. As a result. we get a better trade-off between preserving details and noise filtering.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.370-370
• /
• 2000

In this paper, we design a Multi-Fuzzy model by means of HCM clustering and genetic algorithms for a nonlinear system. In order to determine structure of the proposed Multi-Fuzzy model, HCM clustering method is used. The parameters of membership function of the Multi-Fuzzy ate identified by genetic algorithms. A aggregate performance index with a weighting factor is used to achieve a sound balance between approximation and generalization abilities of the model. We use simplified inference and linear inference as inference method of the proposed Multi-Fuzzy mode] and the standard least square method for estimating consequence parameters of the Multi-Fuzzy. Finally, we use some of numerical data to evaluate the proposed Multi-Fuzzy model and discuss about the usefulness.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.4 s.97
• /
• pp.64-70
• /
• 1999

A new multi-beam optical system is presented on the grounds of tri-positioning systems in this paper. The system has been developed to improve the data transfer rate for the optical disk system. The actuating system is composed of a tracking and focusing actuating system basically and a newly developed beam rotating actuator. The beam rotating actuator is employed in a multi-beam optical system to trace more than one track simultaneously. The multi-beam optics is established through the optical simulation and several experimental trials. The differential phase tracking method is used in the tracking error signal detection based on the only one beam spot. We also analyze the characteristics of multi-beam optical system. The experimental result shows that the multi-beam positioning system has performance adequate to the multi-beam optical disk system.

• Health Policy and Management
• /
• v.22 no.1
• /
• pp.109-128
• /
• 2012

The purpose of this study is to analyze the performance difference between multi-hospitals and free-standing hospitals. Scholars in industrial economics argue that, due to economies of scale and integration, multi-hospital system may have a better performance compared to freestanding hospitals. The study overturned the hypothesis based on a theory. By analyzing 425 acute-care hospitals in Korea, this research shows that multi-hospital systems and market factors, which have been perceived to be strengths to hospitals, are negatively related to hospitals' financial performance. Specifically, the results showed a better performance of freestanding hospitals compared to multi-hospital systems. Higher labor and administrative cost by multi-hospital system may be the reason for the difference, and it means they are not more effective at cost control. Managers in multi-hospital system, therefore, should pay attention on cost-reducing issues to regain managerial efficiency of organizations.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2016.05a
• /
• pp.113-114
• /
• 2016

This paper proposes a technical requirements analysis of implementation of multi-trade prefabrication. Recently, there has been a rise in the use of prefabrication to minimize on-site work for time reduction to increase productivity. Prefabrication technique is evolved into multi-trade prefabrication combining other trades from single-trade prefabrication. For implementation of new technique, not only itself but complementary techniques have to be prepared. In this paper, MEP corridor rack, a major item of multi-trade prefabrication, was implemented in the test bed and its process was analyzed to find out technical requirements. As a result, comparatively high level of IT technique was required for efficient use of multi-trade prefabrication in design, lifting and construction phase. In design phase, component level of BIM library was needed for manufacturing; and in lifting phase, BIM-based site logistics process was required. Also in construction phase, laser scanning was implemented for gathering shape and geometry of the wall and slab that were attached to multi-trade prefabrication module.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.49 no.11
• /
• pp.637-642
• /
• 2000

IEEE 1149.1 boundary scan architecture is used as a standard in board-level system testing. The simplicity of this architecture is an advantage in system testing, but at the same time, it it makes a limitation of applications. Because of several problems such as 3-state net conflicts, or ambiguity issues, interconnect testing for multi-drop multi-board systems is more difficult than that of single board systems. A new approach using IEEE 1149.1 boundary scan architecture for multi-drop multi-board systems is developed in this paper. Adding boundary scan cells on backplane bus lines, each board has a complete scan-chain for interconnect test. This new scan-path insertion method on backplane bus using limited 1149.1 test bus less area overhead and mord efficient than previous approaches.

• Journal of the Korea Society of Computer and Information
• /
• v.23 no.6
• /
• pp.1-7
• /
• 2018

A multi-label classification is to find multiple labels associated with the input pattern. Multi-label classification can be achieved by extending conventional single-label classification. Common extension techniques are known as Binary relevance, Label powerset, and Classifier chains. However, most of the extended multi-label naive bayes classifier has not been able to accurately estimate posterior probabilities because it does not reflect the label dependency. And the remaining extended multi-label naive bayes classifier has a problem that it is unstable to estimate posterior probability according to the label selection order. To estimate posterior probability well, we propose a new posterior probability estimation method that reflects the probability between all labels and labels efficiently. The proposed method reflects the correlation between labels. And we have confirmed through experiments that the extended multi-label naive bayes classifier using the proposed method has higher accuracy then the existing multi-label naive bayes classifiers.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2001.10a
• /
• pp.501-508
• /
• 2001

Free vibration analysis of multi-delaminated composite beam-columns subjected to axial compression load is performed in the present study. In order to investigate the effects of multi-delaminations on the natural frequency and elastic buckling load of multi-delaminated beam-columns, the general kinematic continuity conditions are derived from the assumption of constant slope and curvature at the multi-delamination tip. Characteristic equation of multi-delaminated beam-column is obtained by dividing the global multi-delaminated beam-columns into segments and by imposing recurrence relation from the continuity conditions on each sub-beam-column. The natural frequency and elastic buckling load of multi-delaminated beam-columns according to the incremental load of axial compression, which is limited to the maximum elastic buckling load of sound laminated beam-column, are obtained. It is found that the sizes, locations and numbers of multi-delaminations have significant effect on natural frequency and elastic buckling load, especially the latter ones.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2007.10a
• /
• pp.242-245
• /
• 2007

In the present investigation, the multi-stage warm drawing process was applied to the magnesium alloy AZ31 sheet to examine the feasibility of multi-stage forming process as a high formability product making process. For that purpose, a multi-stage drawing die system with heating module was developed, and the AZ31 sheets of different sizes were consecutively drawn by the multi-stage drawing die. The obtained drawn cups of AZ31 showed that the multi-stage drawing provided the better formability than the single stage drawing in terms of drawing depth without cup defects such as wrinkles or fractures. The sheet formability improvement by using the multi-stage drawing die system against the single stage was also analyzed in terms of the finite element analysis of material state variables evolution.

• Journal of the Korea Safety Management & Science
• /
• v.11 no.1
• /
• pp.87-91
• /
• 2009

본 논문은 상대적으로 새로운 기법인 Parzen Density Estimation과 Multi-class SVM을 이용한 지능형 고장 탐색과 진단 방법을 제안하고 있다. 본 연구에서는 롤링 베어링을 대상으로 고장을 탐색하고 진단하기 위한 방법을 제안하는데 Parzen Density Estimation과 Multi-class SVM은 고장 클래스를 잘 표현할 수 있다. Parzen Density Estimation은 새로운 패턴 데이터의 거절과 알려진 데이터 패턴의 밀도의 평가에 의해 새로운 패턴을 찾아낼 수 있고, Multi-class SVM 기반의 방법은 여러 클래스의 고장을 support vector로 표현하여 고장 패턴을 찾아낼 수 있다. 본 연구에서는 실제의 다중 클래스를 가지는 롤링 베어링의 고장 데이터를 사용하여 고장 패턴을 탐색하는 과정을 보여주는데, 커널함수의 적절한 파라미터의 선택에 의한 Multi-class SVM 기반의 방법이 multi-layer perceptron이나 Parzen Density Estimation 방법보다 우수함을 입증한다.