• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.41 no.2
• /
• pp.1-8
• /
• 2004

This paper presents an optimal robust LQ-PID controller design method for the second order system with time-delay to meet design specifications. By LQR formulation of the second order system with time-delay, the tuning parameters of PID controller are related by weighting factors Q and R of cost function. The selection of weighting factors Q and R are chosen to satisfy such the design specifications as overshoot and settling time.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.7 no.1
• /
• pp.41-55
• /
• 2015

This study is proposed a new hybrid mount having a moving-magnet type electromagnetic actuator to reduce the vibration transmitted from naval shipboard equipment to the structure of the ship's hull. Optimal design specifications are determined through experimental analysis. The detailed design of the hybrid mount is determined through several design steps with electromagnetic numerical analysis using Maxwell Software(S/W). The hybrid mount that combines a rubber mount and an electromagnetic actuator has a fail-safe function for shock resistance. The mount is fabricated and tested using a universal testing machine to evaluate the design specifications. Finally, numerical simulation of the hybrid mount is performed to confirm control performance and applicability.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.19 no.5
• /
• pp.662-668
• /
• 2016

Defense specification suitability review task means to examine whether to need enactment, amendment or abolition of defense specification, and realistic and efficient review environment are urgently needed by improving system. For the promotion of efficient tasks, the cycle of defense specification suitability review needs to be changed to 5 years for active specifications and 10 years for inactive specifications. To simplify the standards of defense specification suitability review, the distinction between prior management items and general management items should be abolished and the number of review items need to be reduced from ten to three. Also, in order to promote substantial defense specification suitability review, a system improvement is needed to utilize retired professionals from defense acquisition related agencies.

• Proceedings of the KSR Conference
• /
• 2000.05a
• /
• pp.618-625
• /
• 2000

In general, a third rail current collecting shoegear is used widely in the light rail transit system, which is more efficient than overhead pantograph. Therefore, Korean standard specifications for the light rail transit prescribes for the application of it. This paper describes the development of third rail current collecting shoegears, which is suitable to Korean situation and satisfied with Korean standard specifications, Two types are developed for steel wheel AGT system and rubber tyred AGT system, and various experiments are executed.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.53.1-53
• /
• 2001

We have used many Instrumentations to acquire the performance data of vehicles for many years. but these could not satisfied with environment specifications (vibration, shock, temperature) and data processing speed to applicate the performance test for armored military vehicles because of having developed as a common vehicles/fixed installation equipments. So new rugged embedded measurement system required to do large data acquisition and high processing speed (Maximum sample rate : 1.25MHz/ch) with rugged environment specifications. We have developed embedded measurement system by using PXI(PCI eXtension for Instrumentation)bus interface which were composed of stand alone controller and versatile data acquisition boards(analog, digital, vision ...

• Steel and Composite Structures
• /
• v.4 no.6
• /
• pp.419-435
• /
• 2004

The safety level of a structural system designed per code specifications can not be inferred directly from the reliability of members due to the load redistribution and nonlinear inelastic structural behavior. Comparison of the system and member reliability, which is scarce in the literature, is likely to indicate any possible inconsistency of design codes in providing safe and economical designs. Such a comparative study is presented in this study for moment resisting two-dimensional steel frames designed per AISC LRFD Specifications. The member reliability is evaluated using the resistance of the beam-column element and the elastic load effects that indirectly accounts for the second-order effects. The system reliability analysis is evaluated based on the collapse load factor obtained from a second-order inelastic analysis. Comparison of the system and member reliability is presented for several steel frames. Results suggest that the failure probability of the system is about one order of magnitude lower than that of the most critically loaded structural member, and that the difference between the system and member reliability depends on the structural configuration, degree of redundancy, and dead to live load ratio. Results also suggest that the system reliability is less sensitive to initial imperfections of the structure than the member reliability. Therefore, the system aspect should be incorporated in future design codes in order to achieve more reliability consistent designs.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.13 no.1 s.53
• /
• pp.145-151
• /
• 2009

The span deflection among the monitoring items of bridge measurement system in real time is representative behaviour and important index of superstructure condition. the limit of span deflection in Standard Specifications for Highway Bridge in Korea has been applied to the method that is making the management-criteria for span deflection in bridge measurement system. But the limit concern mainly serviceability of divers. So it is difficult to find the safety factor of the limit from the viewpoint of bridge safety. This study estimated the safety factor of the limit of span-deflection in Standard Specifications for Highway Bridge in Korea from the viewpoint of bridge safety by the indoor structural test.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.10 no.6
• /
• pp.900-909
• /
• 1999

The receiving part of the RF system for the digital TRS base stations is developed in this paper. Based on the system specifications, the structure of the RF system is accomplished and its block diagram is drawn. The RF system is implemented according to these block diagrams. Subsequently the RF band-pass filter, the low noise amplifier, the automatic level controlled attenuator, the frequency synthesizer and other components for the system are designed and implemented, and a main board to integrate these modules is also manufactured. To lower the noise floor of the system and suppress the RF spurious noise, a PCB layout is performed carefully. For each module consisting of the RF system and the entire system, the performance tests are accomplished to check the specifications.

• Journal of Drive and Control
• /
• v.12 no.4
• /
• pp.77-81
• /
• 2015

In general, the gears of mixer reducer for concrete mixer truck make use of the differential type planetary gear system to rotate mixer drum smoothly on the initial conditions. The planetary gear system is very important part of mixer reducer for concrete mixer truck because of strength problem. In the present study, calculating the gear specifications and analyzing the gear bending & compressive stresses of the differential planetary gear system for mixer reducer are necessary to analyze gear bending and compressive stresses confidently, for optimal design of the planetary gear system in respect to cost and reliability. As a result, analyzing actual gear bending and compressive stresses of the planetary gear system using Lewes & Hertz equation and verifying the calculated specifications of the planetary gear system, evaluate the results with the data of allowable bending and compressive stress from the Stress-No. of cycles curves of gears.

• Journal of Korea Artificial Intelligence Association
• /
• v.2 no.1
• /
• pp.1-6
• /
• 2024

In this paper, we develop an AI-based recommendation system that matches the specifications of smartphones from company 'S'. The system aims to simplify the complex decision-making process of consumers and guide them to choose the smartphone that best suits their daily needs. The recommendation system analyzes five specifications of smartphones (price, battery capacity, weight, camera quality, capacity) to help users make informed decisions without searching for extensive information. This approach not only saves time but also improves user satisfaction by ensuring that the selected smartphone closely matches the user's lifestyle and needs. The system utilizes unsupervised learning, i.e. clustering (K-MEANS, DBSCAN, Hierarchical Clustering), and provides personalized recommendations by evaluating them with silhouette scores, ensuring accurate and reliable grouping of similar smartphone models. By leveraging advanced data analysis techniques, the system can identify subtle patterns and preferences that might not be immediately apparent to consumers, enhancing the overall user experience. The ultimate goal of this AI recommendation system is to simplify the smartphone selection process, making it more accessible and user-friendly for all consumers. This paper discusses the data collection, preprocessing, development, implementation, and potential impact of the system using Pandas, crawling, scikit-learn, etc., and highlights the benefits of helping consumers explore the various options available and confidently choose the smartphone that best suits their daily lives.