• International Journal of Internet, Broadcasting and Communication
• /
• v.14 no.3
• /
• pp.161-170
• /
• 2022

Recently, NAND-type flash memory has been regarded to be new promising storage media for large-scale database systems. For flash memory to be employed for that purpose, we need to reduce its expensive update cost caused by the inablity of in-place updates. To remedy such a drawback in flash memory, we propose a new flash-aware buffering scheme that enables virtual flushing of dirty pages. To this end, we slightly alter the tradional algorithms used for the logging scheme and buffer management scheme. By using the mechanism of virtual flushing, our proposed buffering scheme can efficiently prevent the frequenct occureces of page updates in flash storage. Besides the advantage of reduced page updates, the proposed viurtual flushing mechanism works favorably for shorneing a recocery time in the presense of failure. This is because it can reduce the time for redo actions during a recovry process. Owing to those two benefits, we can say that our scheme couble be very profitable when it is incorporated into cutting-edge flash-based database systems.

• International journal of advanced smart convergence
• /
• v.11 no.3
• /
• pp.42-48
• /
• 2022

Currently, the world is facing severe inflation due to Corona and the war in Ukraine, and it is causing a lot of difficulties for us. Companies are facing a lot of restrictions on their economic activities compared to the past due to supply chain problems and foreign exchange rates. In this situation, many countries have been implementing various smart factory promotion projects to secure competitiveness through productivity improvement in the manufacturing industry. In this study, the contents of smart factory promotion in major countries were reviewed, and problems raised about the implementation of smart factory in Korea, which are being implemented based on this, were described. It is most reasonable to judge the success of a smart factory by the achievement of the performance indicators presented at the time of the project. Therefore, based on the performance index of the business, which is a key factor in determining the success or failure of a smart factory, we investigated whether the company's smart factory promotion can be carried out successfully through examples

• International Journal of Internet, Broadcasting and Communication
• /
• v.16 no.3
• /
• pp.329-333
• /
• 2024

With increasing applications of technologies developed in the Fourth Industrial Revolution, data have come to replace important knowledge and experience in the agricultural field. Although data-based smart agriculture is growing at an average annual rate of 8.57%, research on ways to utilize data produced alongside is remains insufficient. Because such data may considerably help stakeholders involved in agricultural activities, we deployed the prosumer concept to revitalize agricultural data. We systematically structured and defined three relevant entities: the prosumer, which produces and consumes agricultural data; the database, which systematically processes and integrates agricultural data; and the consumer, which utilizes agricultural data in various ways. Our framework is designed to help stakeholders use agricultural data to improve the quality of crops, minimize the failure of agricultural activities, quickly adapt to new environments and methods of crop production, and find effective solutions to relevant issues.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.14 no.6
• /
• pp.139-147
• /
• 2014

The ballast water may be discharged into another sea area with marine organisms, it caused problems to disturb the marine ecosystem. So, in order to remove these environmental risk factors, the IMO has mandated the installation of BWTS to the all ships. Our monitoring system diagnose and predict a failure of BWTS by analyzing the sensor information of BWTS collected from which the ships scattered in the ocean of several. This paper presents the design and implementation of communication modules for BWTS remote monitoring considering the satellite communication charge fee. In the our study, we implemented the safety and cost-saving communication modules by LabVIEW program. The collected sensor informations is encrypted and compressed by LabVIEW modules running on RIO. Then they will be transfer to the land server and will be decrypt to enable monitoring in the land server. For the verification, we build the test modules which can verify from collecting the sensor data to consuming them in the monitoring server. We carried out 20 times for the data pattern in all of case. So, we verified the excellent functionality and reliability through the experimental result.

• Journal of Korean Society for Quality Management
• /
• v.45 no.3
• /
• pp.503-520
• /
• 2017

Purpose: In the near future, it is expected that UGV(unmanned ground vehicle) will be put into battle due to IT technology and unmanned technology development. In this study, we analyze the combat effectiveness considering communication effect where complex combat information and commands are transmitted. Methods: We use ABM(agent-based modeling) and wireless channel module which provides sophisticated communication effect through geographic information and UGV performance. And UGV combat simulation using wireless channel module is used to grasp the combat effectiveness according to the number of packets, which is a unit for storing all information and commands having high complexity. Results: The result of this study is to derive the optimal number of packets which does not decrease the combat effectiveness and the number of lost tanks. The number of packet increases, the survival ratio of our tanks are decreased. Conclusion: In this study, we reveal that the communication success or failure could affect the combat effectiveness. Also, it helps develope the standard communication protocol between UGVs and could be applied to analyze the cost effectiveness analysis in UGV combat environment.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.5
• /
• pp.906-912
• /
• 2012

A ship ad-hoc network (SANET) can provide ships with diverse multimedia services by replacing expensive satellite communications. While ITU-R M. 1842-1, standards for maritime VHF band digital communications, can be used as the specifications of physical layer for SANETs, no standards are specified for higher layers of SANETs. In this paper, we propose a ship ad-hoc communication (SAC) protocol for SANETs, based on medium access control (MAC) and routing protocols for terrestrial ad-hoc networks. SAC protocol is a cross-layer protocol which combines MAC and routing into one algorithm and considers maritime environments, including the existence of neighboring ships, the possibility of routing to a destination, and changing the communication mode in case of VHF channel failure.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.5B
• /
• pp.889-898
• /
• 2000

In order to support various broadband multimedia servies in the future, we designed a well balanced WDM backbone network. In Korean network traffic environment, six regional centers are selected, link capacities between the regional centers are estimated from the PDI traffic model, and the overall network configuration is designed for the all-optical backbone network. Also, we designed a basic configuration to be able to protect minimum communication capability against link failure. A simulation study is carried out to verify the desired performance of the designed WDM backbone network. Simulation results show that performance of the backbone network is well balanced to support various communication services in Korea in the mid 2000s

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.11
• /
• pp.2845-2862
• /
• 1999

As the technical advances in portable computers and wireless communication technologies, mobile computing environment has been rapidly expanded. The mobile users on mobile host can access information via wireless communication from the distributed heterogeneous multidatabase system in which pre-existing independent local information systems are integrated into one logical system to support mobile applications. Hence, mobile transaction model should include not only the features for heterogeneous multidatabase systems but also the ones for mobile computing environment. In this paper, we proposed a mobile flex transaction model which extends the flexible transaction model that previously proposed for heterogeneous multidatabase systems is extended to support the requirements of mobile heterogeneous multidatabase systems. We also presented the execution control mechanism of the mobile flex transaction model. The proposed mobile flex transaction model allows the definition of location-dependent subtransactions, the effective support of hand-over, and the flexibility of transaction executions. Hence, the proposed mobile flex transaction model can be suit to mobile heterogeneous multidatabase systems that have low power capability, low bandwidth, and high communication failure possibility.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.10 no.4
• /
• pp.433-439
• /
• 2015

Enclosures for CCTV internal short circuit are prevented due to wetting to maintain a constant humidity and temperature, to avoid condensation due to temperature difference, a constant temperature and humidity requirements of the equipment, such as high-temperature resistant and a constant temperature of the structure, degree of energy utilization is optimized for developing this corresponding housing automatic control system and humidity is required. Device being an expensive imaging equipment in side of the enclosure according to the temperature conversion from a hazard protection, there is a need for a constant temperature and humidity control apparatus that can prevent a short-circuit failure. This is a system in which the accessory device is absolutely required for the storage and transmission of an image in recording reliability and field conditions.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.66 no.9
• /
• pp.1373-1378
• /
• 2017

This paper presents a basic ECU(Electronic Control Unit) hardware development procedure for the functional safety of in-vehicle network systems. We consider complete hardware redundancy as a safety mechanism for in-vehicle communication network under the assumption of the wired network failure such as disconnection of a CAN bus. An ESC (Electronic Stability Control) system is selected as an item and the required ASIL(Automotive Safety Integrity Level) for this item is assigned by performing the HARA(Hazard Analysis and Risk Assessment). The basic hardware architecture of the ESC system is designed with a microcontroller, passive components, and communication transceivers. The required ASIL for ESC system is shown to be satisfied with the designed safety mechanism by calculation of hardware architecture metrics such as the SPFM(Single Point Fault Metric) and the LFM(Latent Fault Metric).