• 제어로봇시스템학회:학술대회논문집
• /
• 1997.10a
• /
• pp.117-119
• /
• 1997

We consider the control design for nonlinear uncertain systems. The uncertainty is mismatched and possibly fast time-varying. Within the suitable range of the uncertainty the control is valid. No statistical information on uncertainty is imposed. Only the possible bound of the uncertain parameter is known and the control design is based on Lyapunov approach.

• Korean Journal of Computational Design and Engineering
• /
• v.10 no.4
• /
• pp.237-243
• /
• 2005

To increase the productivity and efficiency of an enterprise, all relevant product information should be provided to shop floor workers timely and in a unified form because shop floor workers are final consumers of most accumulated information generated from various departments of an enterprise. But, most existing enterprise information systems have an emphasis upon providing design/manufacturing information to office workers. Proposed in this study is the development of integrated design/manufacturing information system focused on providing cohesive information required to shop floor activities. For developing integrated information system, the functional requirements at the shop floor are identified and analyzed. Based on the extracted functional requirements, object-oriented system design and implementation is conducted. By using this system, shop floor workers can use all relevant information required to their daily operation in a integrated and unified form.

• Journal of Institute of Control, Robotics and Systems
• /
• v.21 no.1
• /
• pp.14-20
• /
• 2015

This paper describes the design of a robust H-infinity attitude controller for a quad-rotor. The linear model of a quad-rotor was estimated using PEM (Prediction Error Minimization) method with experimental input and output data. To design an attitude controller, an extended plant was constructed by adjusting several uncertainties and weighting functions. An H-infinity controller was obtained by applying H-infinity methodology to the extended plant. Through frequency-domain analysis, it was shown that the designed controller can overcome uncertainties up to 75% of the plant model. The performance and robustness of the controller were verified through time-domain simulation.

• Journal of information and communication convergence engineering
• /
• v.16 no.4
• /
• pp.203-212
• /
• 2018

In this article, a novel design of patch antenna with wide band characteristics is presented. The proposed antenna is having electrical dimensions of $0.14{\lambda}{\times}0.11{\lambda}$ (at lower initial frequency) and footprints of $150mm^2$. Structural parameters optimization shows 3.1-23.5 GHz frequency range for a (reflection coefficient) $S_{11}{\leq}-10dB$ and simulated gain 6.8 dB is obtained. An equivalent circuit model is proposed to get an insight view of antenna. Advanced Systems Design (ADS) simulation results are obtain which confirm the validity of proposed model. Degenerated foster canonical form has been used to explain the reactance and capacitive behavior idea of simulated proposed antenna's input impedance later on an equivalent circuit model and smith chart is also suggested. HFSS and CST have been used to analyze antenna behavior. The proposed antenna can be further used for microwave image detection applications.

• Proceedings of the Korea Society for Industrial Systems Conference
• /
• 2006.05a
• /
• pp.229-234
• /
• 2006

E-commerce and business information systems are being introduced in most of enterprises with the development of internet recently. Meanwhile the introduction of enterprise portal concepts and the enterprise informatization provide a necessary premise for insuring a competitive power. Therefore, it became necessary to research on the project of reusing the data of e-commerce. In this paper, we make a domestic maker the subject and implement a XML based electronic catalog(e-catalog) system for electronic commerce(e-commerce) based on web. The implemented XML based e-catalog system can reduce time and expenses needed for making, keeping and distribution in paper catalog systems. It also can correct the data reuse problems in the e-catalog systems implemented by HTML. Exchanging and reusing data used in e-commerce is essential to the integration between business information systems and points to the enterprise portal.

• Journal of Industrial Technology
• /
• v.18
• /
• pp.343-353
• /
• 1998

Effective design of a database is essential for operating application systems efficiently. This paper discusses database design for a geographic information system. This goals of database design are multiple: to satisfy the information content requirements of the specified users and applications; to provide a natural and easy-to-understand structuring of the information; and to support processing requirements and any performance objectives such as response time, processing time, and storage space. Database design is a very complex process and is decomposed in three phases: conceptual, logical, and physical design. In this paper, we first collect and analyze the requirements for a geographic information system. We also perform database design for these requirements through the three design phases systematically. Our results would contribute to the effective construction of a database for a geographic information system.

• 한국디지털정책학회:학술대회논문집
• /
• 2003.12a
• /
• pp.263-273
• /
• 2003

Recognizing the importance of the database query optimization design methods, we implemented mobile database with mobile program (J2ME) which is a useful database procedures. In doing so, we emphasize the logical query optimization which brings mobile database to performance improvement. The research implies that the suggested mobile program (J2ME) would contribute to the realization of the efficient mobile database as the related technology develops in the future.

• Proceedings of the Korea Society for Industrial Systems Conference
• /
• 2001.05a
• /
• pp.129-133
• /
• 2001

Accelerated life test is a viable method for identifying failure modes, incorporating design changes on an on-going basis during the early stages of automotive development program. The information from tests at high stress levels is extrapolated to obtain estimate of life at normal stress levels. This paper presents a practical method for accelerated life test to achieve a specified accuracy in estimating life at a design stress. Recommended and optimum plan are presented and the plans are illustrated with a simulated test data for the automotive power element example.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.16 no.2
• /
• pp.726-741
• /
• 2022

The purpose of this study is to provide instructive theoretical models for art (music) education institutions especially when unpredictable risks, such as pandemics, occur again. Based on the customer behavior theory of the business-to-business-to-customer (B2B2C) platform, and in combination with the technology acceptance model (TAM) and expectation confirmation model (ECM), this study proposes an online education model from the perspective of art education. The framework is based on the three decision-making processes of the customer, and includes the product owner, content owner, and customer area. This paper highlights the factors that influence customers in making decisions when art education institutions are product owners. Regression analysis was introduced to study the factors influencing the expectation confirmation, and the overall fitting testing and six hypotheses testing of 385 effective samples were performed using the structural equation modeling (SEM). The results show that the course-design and after-service positively influenced the expectation confirmation, and the domain image positively influenced the continuance behavior. Negative emotions skipped the mediator (expectation confirmation) and directly exerted a significant negative impact on customers' willingness to continue system usage (continuance behavior). In addition, expectation confirmation positively influenced continuance behavior. The paths of detailed items comprising course-design, after-service, and negative emotion were also analyzed and discussed. In this path analysis, ordinary art learners did not believe that AI partners can play a very good auxiliary role. The findings contribute to the scope of information systems acting as an art education platform academically, and provide effective and theoretical support for the actual operation of art education institutions.

• Transactions of the Society of Information Storage Systems
• /
• v.2 no.1
• /
• pp.21-25
• /
• 2006

The new multimedia information environment requires smaller optical data storage systems. However, one of the difficulties encountered in designing small form factor(SFF) optical pick-up is to emit the heat which is generated from laser diode(LD). Heat generated at the LD can reduce the optical performance of the system and the lifetime of LD. Therefore, it is important to include the thermal design in the design stage of SFF optical pick-up system for high performance and the longer lifetime of LD, and furthermore, to analyze the thermal characteristics of LD in detail micro heat transfer analysis is necessary. In the present study, micro heat transfer analysis was performed using the finite element method for the $28{\times}11{\times}2mm^3$ super slim swing-arm type optical pick-up actuator for Blu-ray disk. Two different materials were used for a swing-arm; a double layer polycarbonate/steel structure and a single aluminum structure.