• Journal of Power Electronics
• /
• v.19 no.1
• /
• pp.265-277
• /
• 2019

The application of shunt active power filters (S-APFs) is considered to be the most popular approach for harmonic compensation due to its high simplicity, ease of installation and efficient control. Its functionality mainly depends upon the rapidness and precision of its internally built control algorithms. A S-APF is generally operated in the current controlled mode (CCM) with the detection of harmonic load current. Its operation may not be appropriate for the distributed power generation system (DPGS) due to the wide dispersion of nonlinear loads. Despite the fact that the voltage detection based resistive-APF (R-APF) appears to be more appropriate for use in the DPGS, the R-APF experiences poor performance in terms of mitigating harmonics and parameter tuning. Therefore, this paper introduces a direct harmonic voltage detection based control approach for the S-APF that does not need a remote harmonic load current since it only requires a local point of common coupling (PCC) voltage for the detection of harmonics. The complete design procedure of the proposed control approach is presented. In addition, experimental results are given in detail to validate the performance and superiority of the proposed method over the conventional R-APF control. Thus, the outcomes of this study approve the predominance of the discussed strategy.

• Current Optics and Photonics
• /
• v.6 no.2
• /
• pp.183-190
• /
• 2022

Based on the linear electro-optic (EO) effect of lithium niobite (LiNbO₃, LN) crystal, an intense two-dimensional (2D) electric field sensor was analyzed, fabricated and experimentally demonstrated. The linear polarized light beam transmits along the optical axis (z-axis) of the LN crystal, and the polarization direction of the polarized light is 45° to the y-axis. The sensor can detect the intensity of a 2D electric field that is perpendicular to the z-axis. Experimental results demonstrated that the minimum detectable electric field of the sensor is 10.5 kV/m. The maximum detected electric field of the sensor is larger than 178.9 kV/m. The sensitivity of the sensor is 0.444 mV/(kV·m^-1). The variation of the sensitivity is within ±0.16 dB when the sensor is rotated around a z-axis from 0° to 360°. The variation of the sensor output optical power is within ±1.4 dB during temperature change from 19 ℃ to 26 ℃ in a day (from 7:00 AM to 23:00 PM) and temperature change from 0 ℃ to 40 ℃ in a controllable temperature chamber. All theoretical and experimental results revealed that the fabricated sensor provides technology for the direct detection of intense 2D electric fields.

• Journal of Korea Society of Industrial Information Systems
• /
• v.22 no.5
• /
• pp.31-37
• /
• 2017

In this Paper, we have Improved the Manufacturing Process of Liquid Aluminum Sulfate using the Design of Automated Measurement Systems. The Manufacturing Process of Liquid Aluminum Sulfate uses a Large Weight. The Quality of a Product Depends Highly on the Proportion of the Raw Material Input in the Production Process. Therefore, it is Very Important to Accurately Measure the Amount of Raw Material. For Automation Design, Load Cell Sensor which can Measure Large Weight Accurately and PLC Technology which is most used in Automation Process are Applied. The Content of Aluminum Oxide in the Aluminum Sulfate Produced before the Automation Design Varies from 8.023% to 8.250%. However, after Automation Design, the Amount of Change from 8.09% to 8.19% was Greatly Reduced. As a Result, we could Reduce the Quality Defect rate Due to Weighing Errors and Reduce Safety Accidents by Applying Automation System.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.3
• /
• pp.470-475
• /
• 2021

This paper analyzed the differences in the relationship between banking service automation and employment by bank ownership type. We found significant differences in the restructuring of the labor force and increasing banking service automation between foreign banks (owned by foreign capital) and local banks. Foreign banks showed the possibilities of reducing the regular labor force through the increase in banking service automation. However, banking service automation in local banks has reduced only the number of irregular employees but increased regular employees. This paper suggests new evidence on the differences between foreign and local banks in banking personnel management with the increase in banking service automation. This paper contributes to the preceding research areas of banking, business, and governance. In addition, this paper provides important insights on banking service automation, employment, and foreign banks for banking managers and policymakers.

• Journal of Institute of Control, Robotics and Systems
• /
• v.17 no.7
• /
• pp.720-729
• /
• 2011

The demand for wireless technology in home automation systems has recently been increasing due to several advantages such as installation cost reduction, easy placement, easy extension, aesthetic benefits, and mobile device connectivity. Among the many wireless technologies, ZigBee is one of the most useful for home automation; a wireless home networking system can be configured using ZigBee alone. Compatibility with conventional home networking systems that are based on wired media, however, is not supported. KNX is a mature protocol for wired media that is recognized as an international standard. This paper proposes a KNX-ZigBee gateway to interface between KNX and ZigBee systems and thereby enable integration of wired and wireless home automation systems.

• Journal of Sensor Science and Technology
• /
• v.26 no.2
• /
• pp.128-134
• /
• 2017

Until now, neuropsychological tests can diagnose the brain dysfunction, however, cannot distinguish the objective data of experiment enough to distinguish the relationships between brain dysfunction and cerebropathia. In this paper, an automatic cognitive test equipment system with 6-axis motion sensors was proposed for the automation of neuropsychological tests. Fist-Edge-Palm(FEP) test and Go-no go test were used to evaluate motor programming of frontal lobe. The motion data from the specially designed motion glove are transmitted wirelessly to a computer to detect the gestures automatically. The healthy 20 and 11 persons are investigated for the FEP and Go-No go test, respectively. The recognition rates of gestures of FEP and Go-No go test are min. 91.38% and 89.09%. In conclusion, the automations of cognitive tests are successful to diagnose the brain diagnostics quantitatively.

• Journal of Electrical Engineering and Technology
• /
• v.11 no.2
• /
• pp.425-436
• /
• 2016

In this paper, a parameter optimization based iterative learning control strategy is presented for permanent magnet synchronous motor control. This paper analyzes the mechanism of iterative learning control suppressing PMSM torque ripple and discusses the impact of controller parameters on steady-state and dynamic performance of the system. Based on the analysis, an optimization problem is constructed, and the expression of the optimal controller parameter is obtained to adjust the controller parameter online. Experimental research is carried out on a 5.2kW PMSM. The results show that the parameter optimization based iterative learning control proposed in this paper achieves lower torque ripple during steady-state operation and short regulating time of dynamic response, thus satisfying the demands for both steady state and dynamic performance of the speed regulating system.

• Journal of Mechanical Science and Technology
• /
• v.15 no.2
• /
• pp.172-179
• /
• 2001

The effects of the interface and two holes located near the crack path in the hybrid specimen on the dynamic crack propagation behavior have been investigated using dynamic photoelasticity with the aid of Cranz-Shardin type high speed camera system. The dynamic stress field around the dynamically propagating interface crack tip in the three point bending specimens under a dynamic load applied by a hammer dropped from 0.6m high without initial velocity are recorded. The complex stress intensity factors for the dynamically propagating interface crack are extracted by using a overdeterministic least square method. Theoretical dynamic interface isochromatic fringe loops generated by using the numerically determined complex stress intensity factors are compared with the experimental results. Furthermore, the influence of the hole to the dynamic interface crack velocities has been investigated experimentally.

• Korean Journal of Computational Design and Engineering
• /
• v.15 no.5
• /
• pp.393-402
• /
• 2010

Existing construction industry is composed of several processes with various characteristics. The tendency of current construction industry is getting complicated and diversified; it has limitation to solve problems through existing processes. As a problem-solving method, BIM (Building Information Modeling), environment to manage building life cycle from design and construction to management, is being suggested. Currently, BIM is only focused on technology development by engineers, and the automation of architectural theories is insufficiency except architectural design modeling. Therefore, this research aims to back up theses drawbacks through intellectual curtain wall arrangement by using musical proportions. In order to apply to construction automation, analysised of musical proportions method are performed. The BPMN-based Process Map is listed to develop IDM for the application to BIM Software.

• Proceedings of the KSME Conference
• /
• 2003.11a
• /
• pp.1757-1762
• /
• 2003

For coping with various ship types easily, welding automation using CAD/CAM is demanded and and developed. In this paper we propose a dedicated CAM system which generates MACRO files to control robot manipulators. The paper contains CAD interface, virtual simulation, macro generation and job schedulling. At first, it defines and extracts weldline from CAD data, and generates proper MACRO programs. And it obtains optimum job schedules. This system removes the manual work, and consequently reduces the overall lead time. And it reduces costs and time for developing robot welding programs. This can be expanded to virtual factory simulation technology. Moreover, it is possible to apply this system for automation of Cutting and Painting