• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.11
• /
• pp.4522-4528
• /
• 2010

The single phase switched reluctance motor has simple, robust structure and economical drive system. So, it is useful to apply in the industrial and home applied machines. Especially, the single phase induction motor, used much in field, has a low efficiency and control ability. For the replacement of it, the single phase SRM is presented. In this paper, the design and characteristics of single phase SRM considering the rotor shape will be presented in the base of general electric motor design method and poly phase SRM design method.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.3
• /
• pp.570-576
• /
• 2004

In this paper, we design the IFFT/FFT (Inverse fast Fourier Transform/Fast Fourier Transform) modules for IEEE 802.11a-1999, which is a standard of the High-speed Wireless LAN using the OFDM (Orthogonal Frequency Division Multiplexing). The designed IFFT/FFT is the 64-point FFT to be compatible with IEEE 802.11a and the pipelined architecture which needs neither serial-to-parallel nor parallel-to-serial converter. We compare four types of IFFT/FFT modules for the hardware complexity and operation : R22SDF (Radix-2 Single-path Delay feedback), the R2SDF (Radix-2 Single-path Delay feedback), R2SDF (Radix-4 Single-path Delay Feedback), and R4SDC (Radix-4 Single-path Delay Commutator). In order to minimize the error, we design the IFFT/FFT module to operate with additional decimal parts after butterfly operation. In case of the R22SDF, the IFFT/FFT module has 44,747 gate counts excluding RAMs and the minimized error rate as compared with other types. And we know that the R22SDF has a small hardware structure as compared with other types.

• Proceedings of the KIEE Conference
• /
• 1999.07g
• /
• pp.3233-3235
• /
• 1999

This paper describes development of a microprocessor-based optoelectronic guard system established a higher level of control reliability in machine guard design. The system uses the design concept of diverse redundancy and a fast software algorithm. We have accomplished an safety light curtain system that allows to be intentionally disabled moving machine by the interrupt of dangerous situations. As a result, it is showed that the proposed system is effective enough to practical applications.

• Journal of Advanced Marine Engineering and Technology
• /
• v.16 no.4
• /
• pp.50-59
• /
• 1992

The paper presents a digital speed control approach of induction motor systems by using a digital servo control method and a well-known second order differential equation as model. The basic concept of using the modeling equation stated in the above is induced from the control theory stand point such that we can describe usually the motor system connected by inverter, generator and load etc, just as a mechanical system to be controlled. The concept does not demand us the complicated vector-based modeling equation adopted in the traditional methods for the speed control of induction motor. Futhermore, the proposed speed control system can be treated as a single input and single output system. The effectiveness of the servo control system obtained by the above-mentioned design concept is illustrated by the experimental results in the presence of both step reference changes and load variations. It is observed from the experimental results that the steady state-error of the experimental set up becomes zero after some regulation time and the induction motor system is robust in spite of reference signal changes and load variations.

• Advances in aircraft and spacecraft science
• /
• v.1 no.4
• /
• pp.427-441
• /
• 2014

Orbit-raising is an important step to place spacecraft from parking orbits into working orbits. Attitude control system design is crucial in the success of orbit-raising. Several text books have discussed this design and focused mainly on the traditional methods based on single-input single-output (SISO) transfer function models. These models are not good representations for many orbit-raising control systems which have multiple thrusters and each thruster has impact on the attitude defined by all outputs. Only one published article is known to use a more suitable multi-input multi-output (MIMO) Euler angle model in spacecraft orbit-raising attitude control system design. In this paper, a quaternion based MIMO model for the orbit-raising attitude control system design is proposed. The advantages of using quaternion based model for orbit-raising control system designs are (a) there is no need for mathematical transformations because the attitude measurements are normally given by quaternion, (b) quaternion based model does not depend on rotational sequences, which reduces the chance of human errors, and (c) the singular point of reduced quaternion model is the farthest from the operational point where linearization is performed. We will show that performance of quaternion model based design will be as good as the performance of Euler angle model based design for orbit-raising problem.

• Structural Engineering and Mechanics
• /
• v.71 no.4
• /
• pp.341-350
• /
• 2019

Exterior beam-column joint is typically the weakest link in a limited-ductile reinforced concrete (RC) frame structure. The use of diagonal haunch element has been considered as a desirable seismic retrofit option for reducing the seismic demand at the joint. Previous research globally has focused on implementing double haunches, while the use of single haunch element as a less-invasive and more architecturally favorable retrofit option has not been investigated. In this paper, the key formulations and a design procedure for the single haunch system for retrofitting RC exterior beam-column joint are developed. An application of the proposed design procedure is then illustrated through a case study.

• Fashion & Textile Research Journal
• /
• v.7 no.1
• /
• pp.23-32
• /
• 2005

This study attempts to address the development processing of yarn-dyeing jacquard design by using jacquard textile design professional CAD system to create high valued worth products. To carry out this purpose, two kinds of necktie samples were designed and each of them was different in three types of weaving method. The results are as follows; All over type is appropriate when the motive's size is small. And the work can be finished within short time and design can be illustrated by basic jacquard system. However, one point type can represent rather big and audacious motive but it needs lots of working hours and jacquard system. Though the motives are identical, showed many changes in cubicle representation according to weaving methods and the structure. To express simple and modest design, single fabric woven is suitable and in the need of colorful and technical design, expressing by double weft cloths and triple weft cloths rather than single fabric woven are better to give creativity and colorfulness. For the production of jacquard design, cad system using ability is important but the understanding and study of the whole process of weaving development should be made.

• Journal of the Korean Society for Precision Engineering
• /
• v.13 no.9
• /
• pp.114-129
• /
• 1996

This paper describes the whole development phase for the underwater vehicle actuating system with high hydroload torque disturbance. This includes requirement analysis, system modeling, control algorithm design, real time implementation, test and performance evaluations. As for driving control algorithms, fuzzy logic, variable structure and PD(Proportional-Differential) algorithm were designed and implemented on board controller using a single chip microprocessor. Intel 8797. And test and performance evaluation is carried out both single test and wystem integration test. We could confirm the basic performance of actuating system through the single test and gereral developing work of any actuating systems was finished with a single performance test of actuating system without system integration test. But, we suggested that system integration test be needed. System integration test is carried out using G/C HILS(Guidance and Control Hardware-In-the -Loop Simulation) which is constituted flight motion simulator, load simulator, real time host computer and the related subsystems such as inertial navigation system, power supply system and Guidance and Control Computer etc.. The most important practical contribution of this paper is that full system characteristics such as minimal control effort, enhancement of guidance and autopilot performance by the actuating system using G/C HILS technique are investigated. Through full running G/C HILS, in spite of the passing to single tests, some control algorithm resulted in failure as to stability of full system and system time frame.

• 한국HCI학회:학술대회논문집
• /
• 2009.02a
• /
• pp.851-854
• /
• 2009

This Research suggest that key features of lighting simulation and intuitive theaterical design method can unify single system. It can produce the virtual scene of stage which is able to predict the number of lighting box and design budget. the final goal of this research is unifying lighting and stage design into on single system.

• Proceedings of the Korea Contents Association Conference
• /
• 2008.05a
• /
• pp.529-533
• /
• 2008

Mission Computer performs important role both managing a whole system and dealing with a specific mission in avionics system. In general, the fault of SPOF(Single Point Of Failure) in unity system can lead to failure of whole system. It can cause a failure of a mission and also can threaten to the life of the pilot. So, in this paper, we design the HA(High-availability) system so that dealing with the failure. And we use HA software like Heartbeat, Fake, DRBD and Bonding to managing HA system.