• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.2
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• pp.312-320
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• 2010

Most online monitoring systems of running currently based on the wired network and local area wireless network generate an increase of administrative costs such as synchronization of data protocol conversion, flexible operation of measurement devices and maintenance. To solve this problem, this paper proposes the SMS data transmission protocol which allows multiple data collecting device to manage effectively including implementation method of cdma-based environmental information monitoring system. Also this paper shows operational safety of the proposed protocol and analyzes efficiency of data transfer and operating using SMS.

• Journal of the Institute of Convergence Signal Processing
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• v.22 no.1
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• pp.38-44
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• 2021

Wi-Fi provides some low-power connection solutions that other Bluetooth cannot provide, and at the same time brings many benefits. First, there is a potentially higher data rate: it can reach 230mbps. Wi-Fi coverage is also wider than competitors, and its operating frequency is also 5GHz, which is much less congested than 2.4GHz. Finally, it also supports IP networks, which is important if you want to send data to the cloud without complexity. The 802.11ac standard of the previous generation still accounts for most shipments (80.9%) and revenue (76.2%). However, there is a limit to accepting IoT devices that will continue to increase significantly in the future. To solve this problem, the new Wi-Fi 6 standard is expected to be the solution (IEEE 802.11ax) which is quickly becoming the main driving force of the wireless local area network (WLAN) market. According to IDC market research analysts, in the first quarter of 2020, independent access points (APs) supported by Wi-Fi 6 accounted for 11.8% of shipments, but 21.8% of revenue. In this paper, we have compared and analyzed the IoT connectivity, QoS, and security requirements of devices using Wi-Fi 6 network.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.11
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• pp.3680-3693
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• 2022

The handover procedure of IEEE 802.11 wireless local area networks (WLANs) introduces significant delay, which can degrade the quality of service (QoS) especially for delay-sensitive applications. Although studies have been conducted to support handover in SDN-based WLAN, there is no research to reduce the channel scanning procedure that takes up the most delay time in the handover process. The channel scanning procedure is essential to determine the appropriate access point (AP). To mitigate this problem, this paper proposes a SWITCH: SDN-WLAN integrated handover scheme for QoS-Guaranteed mobile service. In SWITCH, each AP periodically broadcasts beacon frames through different channels in a predetermined order that includes the operating channel information of the AP. This allows mobile stations (MSs) to receive the beacon frames of nearby APs, and therefore they can determine the appropriate APs for handover without the channel scanning procedure. By reporting the information of the newly moved AP to the SDN controller, a flow rule is installed in advance to provide fast handover, and packet loss is reduced by buffering data destined for MS. In addition, the proposed scheme can adaptively operate SWITCH to consider the user location and QoS requirement of flow to save radio resource overhead. Performance evaluation results demonstrate that SWITCH can reduce the handover delays, flow table utilization ratio and radio resource overhead while improving the network throughput.

• Nuclear Engineering and Technology
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• v.55 no.3
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• pp.839-849
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• 2023

The development of automation technology to reduce human error by minimizing human intervention is accelerating with artificial intelligence and big data processing technology, even in the nuclear field. Among nuclear power plant operation modes, the startup and shutdown operations are still performed manually and thus have the potential for human error. As part of the development of an autonomous operation system for startup operation, this paper proposes an action coordinating strategy to obtain the optimal actions. The lower level of the system consists of operating blocks that are created by analyzing the operation tasks to achieve local goals through soft actor-critic algorithms. However, when multiple agents try to perform conflicting actions, a method is needed to coordinate them, and for this, an action coordination strategy was developed in this work as the upper level of the system. Three quantification methods were compared and evaluated based on the future plant state predicted by plant parameter prediction models using long short-term memory networks. Results confirmed that the optimal action to satisfy the limiting conditions for operation can be selected by coordinating the action sets. It is expected that this methodology can be generalized through future research.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.3
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• pp.19-42
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• 2011

This research focuses on the case studies for operating scheme of technology venture incubation centers located at science parks, technology parks, and foreign universities. Technology venture incubation centers in foreign countries commonly vitalize local economy, create job markets, and promote new venture industry. There is a distinct difference in many ways between foreign and domestic incubation centers. Foreign countries consider the position of incubation centers at national policy level. They characterize the operation of incubation centers into technology fields. They install the networks cooperating with experts and promote the management. Tenant companies moved in incubation centers enhance the degree of completion through industry-university cooperation. Universities and research centers utilize the results of R&D to make the business, accelerate to venture establishment with technical skills, and foster technology entrepreneurs by spin-offs. Through case studies we propose implications helpful to manage domestic technology incubation centers and management methods to be successful centers.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.9
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• pp.841-851
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• 2014

Wireless technologies sharing the same frequency band and operating in the same environment often interfere with each other, causing severe decrease in performance. In this paper, we propose a algorithm based on traffic scheduling techniques that mitigate interference between different wireless systems operating in the 2.4-GHz industrial, medical, and scientific band. In particular, we consider IEEE 802.11 wireless local area networks (WLANs) and Bluetooth data transfer, showing that the proposed algorithms can work when the two systems are able to exchange information as well as when they operate independently of one another. Results indicate that the proposed algorithm remarkably mitigate the interference between the WLAN and Bluetooth technologies at the expense of a small additional delay in the data transfer.

• Journal of Korean Library and Information Science Society
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• v.51 no.1
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• pp.43-70
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• 2020

In the context of accelerating the establishment of specialized libraries, this study aims to reestablish the entire system of specialized libraries scattered by Gimpo City as the Gimpo City Library has been in operation for 20 years. It aims to establish a specialized vision and strategy. In this study, the operational problems of the Gimpo library were discussed from three perspectives. First, there is a problem in selecting a special theme. Next is the problem of using specialized materials. Lastly, it is a matter of not operating the actual specialized program. Based on this analysis, three directions for the development of specialized topics were proposed. First, the selection of specialized topics based on local content and user needs. Second, it is necessary to prepare a plan to activate specialized services. Third, local specialty networks should be strengthened.

• The Korean Journal of Emergency Medical Services
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• v.6 no.1
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• pp.153-168
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• 2002

Since 1992, conventional fire fighting businesses have been converted into a metropolitan autonomous fire fighting system to be ready for a variety of disasters. However, the corresponding investment has been overlapped due to the non-integration of businesses to prevent any potential disasters, and a series of collaborative systems have been not functioning so well. In the meantime, our fire fighting sector has been trying to set up its own clean and faithful position by abolishing any inconvenient system or outsourcing private sectors, and expanded its work scope from conventional fire fighting even to rescue and emergency works. While focusing on handling disaster, the fire fighting sector has been widely trusted and reliable throughtout our nation. Moreover, our fire fighting sector has secured nation wide mobile organizations, technical personnel by field, special equipments and independent communication network. In addition, the fire fighting sector has knowledges, expertise and capabilities required for managing disasters, while in charge of almost every disaster management works including fire, explosion, collapse, disaster and flood. It becomes an organization for comprehensive disaster management under an absolute national trust, which is based on the system for prevention, preparation and countermeasure against a variety of disasters. Thus, our fire fighting sector must make many efforts and try to modernize conventional education and training. The ways to facilitate rescue and emergency works may include the nurture of technical fire fighting personnel along with modernized equipments, the reinforcement of rescue and emergency education, the facilitation of operating civil defense corps, the facilitation of operating volunteer fire fighting corps, the better arrangement of 119 briefing room for public healthcare in provincial offices, the sterilization of rescue instruments and equipments the better repair education for emergency rescue member, the establishment of regional emergency assistant system and the expansion of fire fighting personnel and equipments. In terms of reinforcing the functions and services of rescue 119 and emergency corps, we must review the following considerations: Building up security system along with operational expansion, building up a system for emergency medical treatment, building up a comprehensive information management system for rescue and emergency, constructing a provincial safety museum and so forth. For the ways to better the works of rescue 119 we can review the following considerations : Improving the education for fire fighting training corps under Jeju Provincial Fire and Disaster Management Department, providing rescue members with more opportunities for clinical practices, enhancing the morale of rescue members, installing a comprehensive briefing room for emergency rescue members, building up medical networks along with reasonable policies for information service, operating the consulting system for rescue 119 and so on. If these requirements are met, it is expected that the fire fighting departments in Jeju province can cope with every accident and disaster a little more rapidly and quickly in compliance with local needs, so that they can keep their own position as a public fire fighting organization which may be trusted by the public.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.10
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• pp.1189-1196
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• 2015

In this paper, a microstrip-fed multiband monopole antenna for GPS(Global positioning system)/WiMAX(:Worldwide interoperability for microwave access)/WLAN(Wireless Local Area Networks) for applications was designed, fabricated and measured. The proposed antenna is based on a microstrip-fed structure, and composed of two rectangular double rings and L strips pair and then designed in order to get triple band characteristics. To obtain the optimized parameters, we used the simulator, Ansoft's High Frequency Structure Simulator(HFSS). The proposed antenna is made of $27.0{\times}54.0{\times}1.0mm3$ and is fabricated on the permittivity 4.4 FR-4 substrate. The experiment results shown that the proposed antenna obtained the -10 dB impedance bandwidth 300 MHz (1.325~1.625 GHz), 400 MHz (2.275~2.675 GHz), and 600 MHz (3.15~3.75 GHz) covering the GPS/WiMAX/WLAN bands. Also, the proposed antenna measured gain and radiation patterns characteristics for required operating bands.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.4
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• pp.441-448
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• 2015

In this paper, a CPW-fed dual-band monopole antenna with two branch strips for WLAN(Wireless Local Area Networks) applications was designed, fabricated and measured. The proposed antenna is based on a CPW-feeding structure, and composed of two branch strips and then designed and tuned the length of two branch lines to obtained required frequencies bands. To obtain the optimized parameters, we used the simulator, Ansoft's High Frequency Structure Simulator(HFSS) and carried out simulation about parameters $L_5$, $L_8$, $W_3$, $W_5$, $W_9$. The proposed antenna is fabricated on the FR-4 substrate using the obtained parameters. The numerical and experiment results demonstrated that the proposed antenna obtained the -10 dB impedance bandwidth 1,095 MHz (1.57~2.665 GHz) for 2.4 GHz band and 1,680 MHz (4.99~6.67 GHz) for 5 GHz band satisfied requirement while simultaneously covering the WLAN bands. And characteristics of gain and radiation patterns are determined for WLAN operating bands.