• Journal of Korea Society of Industrial Information Systems
• /
• v.25 no.2
• /
• pp.49-56
• /
• 2020

We investigate the transmit power control algorithm for multi-access points environment. Each terminal may transmit a signal to one of these access points. Each access point may receive a signal from desired terminals as well as interference from neighbor terminals. In this paper, a transmit power control algorithm is developed such that the total transmit power is minimized, while each terminal meets the target signal to interference ratio (SIR) requirement. In particular, the effect of increasing the number of access-points on the total transmit power consumption is analyzed. Based on this analysis, we propose a convergence guaranteed power control algorithm. We prove that the proposed iterative algorithm always converges to the target SIR. In addition, we show that the proposed algorithm optimizes the transmit power level. Simulation results show that the proposed algorithm guarantees convergence regardless of the number of access points. We also observed that increasing the number of access points reduces the total transmit power consumption.

• Journal of Advanced Navigation Technology
• /
• v.27 no.1
• /
• pp.111-118
• /
• 2023

For the implementation of a smart factory, it is necessary to collect data by connecting various sensors and devices in the manufacturing environment and to diagnose or predict failures in production facilities through data analysis. In this paper, to predict the residual useful lifetime of milling insert used for machining products in CNC machine, weight k-NN algorithm, Decision Tree, SVR, XGBoost, Random forest, 1D-CNN, and frequency spectrum based on vibration signal are investigated. As the results of the paper, the frequency spectrum does not provide a reliable criterion for an accurate prediction of the residual useful lifetime of an insert. And the weighted k-nearest neighbor algorithm performed best with an MAE of 0.0013, MSE of 0.004, and RMSE of 0.0192. This is an error of 0.001 seconds of the remaining useful lifetime of the insert predicted by the weighted-nearest neighbor algorithm, and it is considered to be a level that can be applied to actual industrial sites.

• Journal of Broadcast Engineering
• /
• v.25 no.4
• /
• pp.487-496
• /
• 2020

For the purpose of next generation technology for robot perfomances, a RAoRA (Robot Actor on Robot Arm) structure was proposed using a robot arm joined with a humanoid robot actor. Mechanical analysis, machine design and fabrication were performed for motions combined with the robot arm and the humanoid robot actor. Kinematical analysis for 3D model, spline interpolation of positions, motion control algorithm and control devices were developed for movements of the robot actor. Preliminary visualization, simulation tools and integrated operation of consoles were constructed for the non-professionals to produce intuitive and safe contents. Air walk was applied to test the developed platform. The air walk is a natural walk close to a floor or slow ascension to the air. The RAoRA also executed a performance with 5 minute-running time. Finally, the proposed platform of robot performance presented intensive and live motions which was impossible in conventional robot performances.

• Journal of the Korean Institute of Gas
• /
• v.2 no.3
• /
• pp.54-59
• /
• 1998

As distributed control systems (DCS) and plant information systems (PIS) are introduced into gas industries, process monitoring systems based on process data have attracted significant interests. However, these technologies have not been fully due to strong nonlinearities of batch processes. The multiway principal component analysis, which has been recently developed, has solved these problems and has been widely used in the industries. However, the lack of statistical background of process operators has been one of major obstacles for maximum utilization of the technology This paper introduces a real time monitoring system for batch gas manufacturing processes that offers a variety of tools that operators can understand and use without serious difficulties. The proposed integrated system covers the whole spectrum of monitoring and diagnosis that include data collection, monitoring and diagnosis. The developed system has been verified to be very effective for monitoring and diagnosis using its application to the construction of monitoring system for a typical industrial batch reactor.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.47 no.5
• /
• pp.50-60
• /
• 2010

For the last half a century, the personal computer and software industries have been prosperous due to the incessant evolution of computer systems. In the 21st century, the embedded system market has greatly increased as the market shifted to the mobile gadget field. While a lot of multimedia gadgets such as mobile phone, navigation system, PMP, etc. are pouring into the market, most industrial control systems still rely on 8-bit micro-controllers and simple application software techniques. Unfortunately, the technological barrier which requires additional investment and higher quality manpower to overcome, and the business risks which come from the uncertainty of the market growth and the competitiveness of the resulting products have prevented the companies in the industry from taking advantage of such fancy technologies. However, high performance, low-power and low-cost hardware and software platforms will enable their high-technology products to be developed and recognized by potential clients in the future. This paper presents such a platform for industrial embedded systems. The platform was designed based on Telechips TCC8300 multimedia processor which embedded a variety of parallel hardware for the implementation of multimedia functions. And open-source Embedded Linux, TinyX and GTK+ are used for implementation of GUI to minimize technology costs. In order to estimate the expected performance and power consumption, the performance improvement and the power consumption due to each of enabled hardware sub-systems including YUV2RGB frame converter are measured. An analytic model was devised to check the feasibility of a new application and trade off its performance and power consumption. The validity of the model has been confirmed by implementing a real target system. The cost can be further mitigated by using the hardware parts which are being used for mass production products mostly in the cell-phone market.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.6B
• /
• pp.527-533
• /
• 2006

In this paper, we analyze the performance of MAC (Media Access Control) layer in DSRC (Dedicated Short Range Communication). It will be widely applied for ITS (Intelligent Transportation System) services; for example ETC (Electric Toll Control), BIS (Bus Information System) etc., needed to small packet size. But If ITS service is evolving to advance ITS, ADIS (Advanced Driver Information Systems) and AVHS (Advanced Vehicle Highway System) etc, be needed larger packet size. In the future, it may offer more various services such as traffic information, collection, and multimedia information. There are two kind of physical media, IR(Infrared) and RF(Radio frequency). And each system has their own protocol that is adaptive in special characteristics of physical medium for using efficiently limited radio resources. In this paper, we analyze the special characteristics of each system. And we study practical use of some related services expected to be used in the near future, by analyzing the transmission efficiency in each DSRC system.

• Proceedings of the Korean Information Science Society Conference
• /
• 2010.06d
• /
• pp.212-216
• /
• 2010

오늘날 세계화와 정보통신 분야의 기술혁신으로 기업들의 경영활동 영역이 점점 글로벌화 되어가면서 물류산업의 환경도 급격히 변화해 나가고 있다. 세계적으로 확산되고 있는 인터넷망이나 물류망은 시간과 거리의 제약을 완화시켰으며, 고객들의 정보와 상품에 대한 접근이 쉬워짐에 따라 기업에 대한 고객욕구가 다양해지고 있는 실정이다. 이러한 경영환경의 변화에 따라 우리 기업들은 보다 경쟁력 있는 물류서비스를 고객에게 제공하기 위하여 물류 서비스의 유연성 개선, 물류 전문 인력 확보 등에 힘쓰는 한편 물류 부문의 취약성을 극복하기 위한 물류자동화 시스템 도입 등 다양한 방안을 강구하고 있다. 현재 도입된 수배송 관제 시스템은 GPS를 기반으로 하고 있다. 그러나 기존의 GPS를 이용한 관제 시스템은 위치 정보만 수신하여 위성의 사각지역 또는 실내에서 작동이 잘 되지 않는 문제가 있다. 이러한 문제를 해결하기위해 본 논문에서는 스마트폰을 사용한 수배송 관제 시스템을 설계하였다. 스마트폰은 GPS와 3G통신 모두 이용하여 양방향으로 통신할 수 있으므로 기존의 GPS를 이용한 단방향 수배송 관제 시스템보다 정보를 정확하고 효율적으로 관제할 수 있다. 제안하는 시스템은 물류 수배송 상에서 발생되는 데이터를 실시간 모니터링이 가능해야하며, 관리자와 수배송자간의 신속한 정보 전달을 통해 배송조건을 최적화시키고, 물류의 흐름을 제어하여 배송 시에 발생하는 문제에 대한 신속한 해결을 통해서 배송시간을 최소화하는 것이 목적이다.

• Journal of Digital Convergence
• /
• v.14 no.11
• /
• pp.143-148
• /
• 2016

There is increasing concern about security as a need for increased safety in the information industry society. However, it does not meet the needs for safety including CCTV. Therefore, in this paper, we link the processing technology using the image information to the IPS system consisting of GPS and Beacon. It designed a conventional RFID tag attached discomfort and image tracking system is limited to complement the disadvantages identifiable area. To this end, we designed a smart device and the Internet of Things convergence system and a research to ensure the accuracy and reliability of the IPS of the access control system. Finally, by leveraging intelligent video information using a PTZ camera, and set the entrant management policies it was carried out to control the situation and control. Also, by designing the integrated video tracking system, an authentication server, visualization systems were designed to establish an efficient technique for analyzing the IPS entrant behavior patterns.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.10
• /
• pp.3885-3892
• /
• 2010

Safety-Critical systems, such as Plant Protection Systems in nuclear power plant, plays a key role that the facilities can be operated without undue risk to the health and safety of public and environment, and those systems shall be designed, fabricated, installed, and tested to quality standards commensurate with the importance of the functions to be performed. Computer-based Instrumentation and Control Systems to perform the safety-critical function have Real Time Operating Systems to control and monitoring the sub-system and executing the application software. The safety-critical Real Time Operating Systems shall be designed, analyzed, tested and evaluated to have capability to maintain a high integrity and quality. However, local nuclear power plants have applied the real time operating systems on safety critical systems through Commercial Grade Item Dedication method, and this is the reason of lack of detailed methodology on assessing the safety of real time operating systems, expecially to the new developed one. This paper presents the methodology and experiences of safety evaluation on safety-critical Real Time Operating Systems based upon design requirements. This paper may useful to develop and evaluate the safety-critical Real Time Operating Systems in other industry to ensure the safety of public and environment.

• Journal of Korea Multimedia Society
• /
• v.14 no.6
• /
• pp.794-801
• /
• 2011

Main machinery in the factory have various digital indicator to display its operating data for the manager. It is useful to control these datum at the remote office for factory automation in order to increase machine productivity. It is easy to use Ethernet infrastructure for remote communication. But most of all machinery in domestic factories still support RS232c or RS485 serial communication way. In this case to control machinery datum on the ethernet base, it is need to change RS232C or RS485 data to ethernet base. In this paper, in order to develop a remote progress management system through the wireless Internet, we show a design method to make easy maintenance by developing the system with both the JAVA language and RxTx Package for RS232c serial communication. For the system implementation, we added the digital indicator connect with a thermo couple to a machine which provide the real time status data of temperature. To connect machines management server program, we set up a convertor to change the RS485 data to the RS232c and also another convertor to change the RS232c data to wireless ethernet.