• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.16-20
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• 1988

This paper presents a new algorithm for solving the inverse kinematics in real-time applications. The end-tip movement of each link can be resolved into the basic resolution unit, .DELTA.l, which depends on link length, reduction ratio and resolution of the incremental encoder attached to the joint. When x- and y-axis projection of the end-tip movement are expressed in .DELTA.l unit, projectional increments .DELTA.x and .DELTA.y become -1, 0 or I by truncation. By using the incremental computation with these ternary value and some simple logic rules, a coordinate transformation can be realized. Through this approach, it should be noted that the floating-point arithmetic and the manipulation of trigonometric functions are completely eliminated. This paper demonstrates the proposed method in a parallelogram linkage type, two-link arm.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.9
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• pp.908-913
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• 2014

In this paper, we propose a method by which QP (Quadratic Programming) problems can be solved in realtime so that we can implement the predictive control algorithm on a microcontroller system. Firstly, we derive a solution to QP problems by converting the original QP problems to its equivalent least squares with inequalities. Secondly, we propose a predictive control algorithm that can give good realtime computation performance by utilizing the fact that some parameters needed for solving QP problems can be computed offline. Finally, we illustrate that the proposed method can give good realtime features by running the C-code application constructed using the proposed method on a microncontroller system.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.125-128
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• 2002

This paper designed a cipher process, which used SEED-Algorithm that is totally domestic technique. This cipher processor is implemented by using SEED-cipher-Algorithm and pipeline scheduling architecture. The cipher is 16-round Feistel architecture but we show just 16-round Feistel architecture for brevity in this thesis. Of course, we can get the result of the 16-round processing by addition of control part simply. Furthermore, it has pipelined architecture, so the speed of cipher process is the faster than others when we performed a cipher a lot of data. The schedule-function can performed the two-cipher process simultaneously, such as using two-cipher processors.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.313-316
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• 2002

(Korea Information Security Agency) is designed by using VHDL to Implement hardware architecture It has been adopted by most of the security systems in Korea SEED Is designed to utilize the S-boxes and permutations that balance with the current computing technology It has the Feistel structure with 16 rounds The same procedure for data encryption and decryption makes possible an easy and practical hardware implementation. The primary functions used In SEED are F function and G function. This paper proposes an Iterative architecture of F function, a modified architecture of G function and an Iterative architecture of key scheduling algorithm. The designed SEED encrypts and decrypts exactly the test vectors It is expected to extend to various application fields If the design of control blocks Is added.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.65-68
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• 2003

In this paper, a speech recognition system using a speaker defendant algorithm is implemented on the PC. Results are loaded on a LDM display system that employs Intel StrongArm SA-1110. This research has completed so that this speech recognition system may correct its shortcomings. Sometimes a former system is operated by similar speech, not a same one. To input a vocalization is processed two times to solve mentioned defects. When references are creating, variable start-point and end-point are given to make efficient references. This references and new references are changed into feature parameter, LPC and MFCC. DTW is excuted using feature parameter. This security system will give user permission under fore execution have same result.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.3
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• pp.23-36
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• 1997

In tis paper, sthe new data model for the hardware implementation of lempel-ziv compression algorithm was proposed. Traditional model generates the codeword which consists of 3 bytes, the last symbol, the position and the matched length. MSB (most significant bit) of the last symbol is the comparession flag and the remaining seven bits represent the character. We confined the value of the matched length to 128 instead of 256, which can be coded with seven bits only. In the proposed model, the codeword consists of 2 bytes, the merged symbol and the position. MSB of the merged symbol is the comression flag. The remaining seven bits represent the character or the matched length according to the value of the compression flag. The proposed model reduces the compression ratio by 5% compared with the traditional model. The proposed model can be adopted to the existing hardware architectures. The incremental factors of the compression ratio are also analyzed in this paper.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.12
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• pp.1066-1072
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• 2013

In this work, active control algorithm is adopted to reduce delamination effects of the damaged composite structure and control performance with MFC actuator is numerically evaluated. Finite element model for the damaged composite structure with piezoelectric actuator is established based on improved layerwise theory. In order to achieve high control performance, MFC actuator, which has increased actuating force, is considered as a piezoelectric actuator. Mode shapes and corresponding natural frequencies for the damaged smart composite structure are studied. After design and implementation of active controller, dynamic characteristics of the damaged smart composite structure are investigated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.254-258
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• 1996

In this paper, we proposed realtime visual tracking system of moving object for 2D target using extended Kalman Filter Algorithm. A targeting marker are recongnized in each image frame and positions of targer object in each frame from a CCD camera while te targeting marker is attached to the tip of the SCARA robot hand. After the detection of a target coming into any position of the field-of-view, the target is tracked and always made to be located at the center of target window. Then, we can track the moving object which moved in inter-frames. The experimental results show the effectiveness of the Kalman filter algorithm for realtime tracking and estimated state value of filter, predicting the position of moving object to minimize an image processing area, and by reducing the effect by quantization noise of image

• Journal of the Korean Society for Precision Engineering
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• v.18 no.9
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• pp.71-81
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• 2001

This paper analyzes the effectiveness of minimizing vibration and sound transmission on/through a thin rectangular plate by both feedback control and hybrid control which combines adaptive feedforward control with a feedback loop. An experimental system identification technique using the matrix-fractional curve-fitting of the frequency response data is introduced for complex shaped structures. This identification technique reduces the model order o the MIMO(Multi-Input Multi-Output) system which simplifies the practical implementation. The adaptive feedforward control uses a Multiple filtered-x LMS(Least Mean Square) algorithm and the feedback control uses a multivariable digital LQG(Linear Quadratic Gaussian) algorithm. Experimental results show that an effective reduction of sound transmission is achieved by the hybrid control scheme when both vibration and noise measurement signals are incorporated in the controller.

• Smart Structures and Systems
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• v.8 no.5
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• pp.449-470
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• 2011

During the last thirty years many structural control concepts have been proposed for the reduction of the structural response caused by earthquake excitations. Their research and implementation in practice have shown that seismic control of structures has a lot of potential but also many limitations. In this paper the importance of two practical issues, time delay and saturation effect, on the performance of controlled structures, is discussed. Their influence, both separately and in interaction, on the response of structures controlled by a modified pole placement algorithm is investigated. Characteristic buildings controlled by this algorithm and subjected to dynamic loads, such as harmonic signals and actual seismic events, are analyzed for a range of levels of time delay and saturation capacity of the control devices. The response reduction surfaces for the combined influence of time delay and force saturation of the controlled buildings are obtained. Conclusions regarding the choice of the control system and the desired properties of the control devices are drawn.