• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.2
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• pp.49-57
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• 2003

In this paper, is proposed an anti-swing control algorithm for the automation of overhead crane. The algorithm consists of three parts, the FCL with compensatory FLC which generates acceleration, velocity and position reference to reduce swing angle and acceleration feedback controller which feedback control errors. Especially the algorithm dose not need angular sensor which detect swing angle of payload and requires high cost. By the simulation study and experiment with prototype crane, we showed the usefulness of the proposed algorithm.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1225-1228
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• 2011

This paper presents an advanced energy saving algorithm in building. It is important to aggregate a various demand side resource which is controllable on demand response environment. Previous demand side algorithm for building is restricted on peak power. In this paper, we suggest duty cycle algorithm for AHU on demand response to reduce the quantity of building power consumption. The test results show that the proposed algorithm is very effective.

• International Journal of Control, Automation, and Systems
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• v.2 no.2
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• pp.165-170
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• 2004

RAIM techniques based on TLS have rarely been addressed because TLS requires a great number of computations. In this paper, the particular form of the observation matrix H, is exploited so as to develop a new TLS-based sequential algorithm to identify an errant satellite. The algorithm allows us to enjoy the advantages of TLS with less computational burden. The proposed algorithm is verified through a numerical simulation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.615-616
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• 2017

Recently, research are being conducted to provide an automated environment utilizing various sensors in a place where management is use. However, in an existing automation system environment because the measured sensor data is processed in a batch in the server, than the currently action task there arises a problem that a conflict occurs between task when a task that should operate preferentially occurs. In this paper, we propose a system that provides automation using Sensor Data Identification Algorithm to solve these problems. The algorithm distinguishes between real-time and non-real-time tasks and automatically control tasks what happens after priority is applied. Through this, it is expected that it can reduce manager intervention and reduce unnecessary work operation and power consumption and construct an efficient automation environment.

• Journal of Power Electronics
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• v.19 no.6
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• pp.1505-1514
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• 2019

The permanent magnet synchronous motor (PMSM) is widely used in various fields and the proportional-integral (PI) controller is popular in PMSM control systems. However, the motor parameters are usually unknown, which can lead to a complicated PI controller design and poor performance. In order to design a PI controller with good performance when the motor parameters are unknown, a control algorithm based on stability margin is proposed in this paper. First of all, based on the mathematical model of the PMSM and the least squares (LS) method, motor parameters are estimated offline. Then based on the estimation values of the motor parameters, natural angular frequency and phase margin, a PI controller is designed. Performance indices including the natural angular frequency and the phase margin are used directly to design the PI controller in this paper. Scalar functions of the d-loop and the q-loop are selected. It can be seen that the designed controller parameters satisfy Lyapunov large scale asymptotic stability theory if the natural angular frequencies of the d-loop and the q-loop are large than 0. Experimental results show that the parameter estimation method has good accuracy and the designed PI controller proposed in this paper has good static and dynamic performances.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.66 no.3
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• pp.110-116
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• 2017

System to automate the trial-run of energy storage system for frequency regulation was developed and demonstrated. Basic strategy was developed on the basis of trial-run procedure and verified in the computer simulation tool. The algorithm was developed and coded for 4MW trial-run automation system. 4MW trial-run automation system was connected to 4MW energy storage system for frequency regulation in Jocheon substation of Jeju city and demonstrated. 24MW trial-run automation system was developed on the basis of 4MW trial-run automation system and verified by operation system for 24MW energy storage system for frequency regulation. The operation system has own simulation model of energy storage system and power system. The verification was performed to improve the system in the view of user. 24MW trial-run automation system was demonstrated in 32MW Ul-san and 36MW Non-gong energy storage system. All tests of trial-run was done by manual and first they ware taken 1 week with no trial-run automation system. The manual trial-run tests were taken by maximum three times. Trial-run test by trial-run automation system was taken 2 days. The system helps reduce the trial-run test period and improve the accuracy of tests.

• The Journal of Society for e-Business Studies
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• v.24 no.4
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• pp.17-30
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• 2019

The rapid development of a software-core society emphasizes the importance of software competence as a basic condition for all academic disciplines. The purpose of this study is to investigate the difference of perceptions among students of basic software education which is currently being conducted in university. The results of applying the nine core elements of Computational Thinking for Problem Solving to the learners of the each majors are as follows. In humanities, learners mainly applied the elements of Data Collection, Problem Decomposition and Automation. On the other hand, natural science department learners mainly applied the elements of Data Analysis, Algorithm and Automation. In addition, arts learners mainly applied elements of Data Representation, Abstraction, and Automation. To apply Computational Thinking to the development of software, humanities learners mainly applied elements of Data Collection, Algorithm, Automation. On the other hand, natural science department learners mainly applied the elements of Data Analysis, Algorithm and Automation. In addition, arts learners mainly applied elements of Data Representation, Abstraction, and Automation. Based on the results of this study, it is expected that the educational effectiveness of the learner will be maximized by including the learner analysis with each majors in the design of the basic software curriculum that each university is conducting.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.11 no.2
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• pp.137-145
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• 1986

The contention resolution algorithm with the limited packet delay time as well stable distribution as the packet delay time is proposed and implementes for improving the mean packet delay time in the network employing CSMA/CD as the access method. The implementation of node controller is based on IEEE 802.2 standard logical link control(LLC) and IEEE 802.3 standard medium access control(MAC). Some portion of IEEE 802.3 Standard MAC, and the Binary Exponential Back-off(BEB) algorithm is replaced by the proposed algorithm. From the view of normalized mean packet transmission delay time, the controller implemented here can be applicable to the office-automation system, and the factory-and laboratory-automation environment where the limited time criterion is very significant.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.2
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• pp.445-466
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• 2022

As everything linking to the internet, people can subscribe to various services from a service provider to facilitate their lives through the Internet of Things (IoT). An obligatory thing for the service provider is that they should push the service data safely and timely to multiple IoT terminal devices regularly after the IoT devices accomplishing the service subscription. In order to control the service message received by the legal devices as while as keep the confidentiality of the data, the public key encryption algorithm is utilized. While the existing public encryption algorithms for push service are too complicated for IoT devices, and almost of the current subscription schemes based on push mode are relying on centralized organization which may suffer from centralized entity corruption or single point of failure. To address these issues, we design a secure subscription-push service scheme based on blockchain and edge computing in this article, which is decentralized with secure architecture for the subscription and push of service. Furthermore, inspired by broadcast encryption and multicast encryption, a new encryption algorithm is designed to manage the permissions of IoT devices together with smart contract, and to protect the confidentiality of push messages, which is suitable for IoT devices. The edge computing nodes, in the new system architecture, maintain the blockchain to ensure the impartiality and traceability of service subscriptions and push messages, meanwhile undertake some calculations for IoT devices with limited computing power. The legalities of subscription services are guaranteed by verifying subscription tags on the smart contract. Lastly, the analysis indicates that the scheme is reliable, and the proposed encryption algorithm is safe and efficient.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.803-806
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• 1998

This thesis proposes a new heuristic algorithm of integrated allocation and binding for high level synthesis. The proposed algorithm simultaneously allocates binds functional units, interconnections and registers by considering interdependency between operations and storage elements in each control step, in order to share registers and interconnections connected to functional units, as much as possible. This thesis shows the effectiveness of the algorithm by comparing the results of out experiments with those of existing system.