• Proceedings of the KIEE Conference
• /
• 2004.11c
• /
• pp.89-91
• /
• 2004

In SCADA systems, an RTU is a device installed at a remote location that collects data, codes the data into a format that is transmittable and transmits the data back to a central station, or MTU. An RTU also collects information from the master device and implements processes that are directed by master device. RTUs are equipped with input channels for sensing or metering, output channels for control, indication or alarms and a communications port. In general, the data are transmitted via a wired communication infrastructure such as RS422 or RS485 between RTU and MTU. But, limited range of wired communication doesn't allow the system to cover remote areas over the limitation, and building a wired communication network is not easy in the circumstances. In this Paper, we design and implement a smart cost-effective Web-RTU that can communicate with MTU via Web. Web is of benefit to the Web-RTU, because it is not only free from the distance limitations, but also is built easily and cost-effectively wherever Internet resources are available. Additionally, Web can be easily applied to the SCADA system with the development of hardware and software for communications. The Web-RTU has a program memory, a data memory and a RAM inside, and uses Atmega128, low-cost 8 bit micro-processor with eight AI(Analog Input). It performs well enough to implement all existing roles of RTU.

• Journal of Information Technology Services
• /
• v.8 no.1
• /
• pp.193-202
• /
• 2009

Cloud computing emerges as a new computing paradigm which targets reliable and customizable services. The term builds on decades of research in virtual machine, distributed and parallel computing, utility computing, and more recently networking, web service, and software as a service. In this paper, we provide a seamless connection migration of web services. This is useful for cloud computing environment in which many client terminals have mobility. With the wireless internet facility, those mobile users can move place to place during internet communication. Therefore, we provide solutions to the two major problems in current virtualization based migration: communication failure problems and connection re-establishment. Communication channel flushing by zero window notification helps to resolve the communication failure problems and TCP port inheritance prevents connection re-establishment errors during socket reconstruction. Thus, our web service migration facility is now able to preserve open network connections, and even for server sockets. This is a highly transparent approach, in that we did not Introduce additional messages for channel flushing and did not make any modification to the TCP protocol stack. Experimental results show that the overhead due to connection migration of web services is almost negligible when compared with time to take the conventional web service migration.

• Proceedings of the Korea Society of Design Studies Conference
• /
• 2001.05a
• /
• pp.56-57
• /
• 2001

• Archives of design research
• /
• v.16 no.3
• /
• pp.351-360
• /
• 2003

The concept of genre used to be applied to classify the fine arts also can investigate various way of communication system and classification. The structuring element of genre was identified by form and contents in that field. But the classification of the web, which is new communication tool, was made by defining the purpose of the web. In this paper the genre system, which consists of form, contents, and function, is applied to classify the web so that we offer tile opportunity to identify dearer characteristics of it. In order to investigate the genre elements in the communication process the structure of the semiotic triad after Charles S. Peirce was adapted, which was labeled as representamen, object, and interpretant. The representamen substitutes for the web function, the object does for the form of the web, and the representamen does for the web contents. According to the Peirce's the representamen identify the object but on the other hand it is identified by the interpretant. Logical structure of the fact that form of the web is identified by its function, and the function is identified by the contents is proved by following the theory. Therefore, the concept of web genre is supported by the element of genre having a logical structure activating in the communication process. We suggest that in recent complicated communication circumstance the genre concept should be adapted to implement the effective web communication design.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.13 no.3
• /
• pp.517-524
• /
• 2018

This Paper presents the real time things control method through Web browser that has no limited by time and place. To design and realize the system that not only makes it possible to communicate with other protocols but also reinforces the advantages of each protocol, the real time communication environment, based on the WebSocket technology of HTML5 whose international standardization has recently been completed, is realized. Also, the message communication environment in the low electricity and limited communication environment is realized using MQTT(Message Queue Telemetry Transport) protocol which is in the spotlight as the optimum protocol in the IoT environment. And by designing intuitive and simple hardware and realizing the responsive web interface which is not limited by the user's contact devices, the interactive system in which the user receives real time data from the hardware and reversely the user controls the things is designed and realized.

• Proceedings of the IEEK Conference
• /
• 1998.06a
• /
• pp.557-560
• /
• 1998

In this paper, we presetn the WWW (world-wide-web) base dtelePACS, which uses the communication network as asymmetric satellite data communication system (ASDCS). Web-based telePACS is imple-mented with JAVA language. Through the internet, web-based TelePACS can make it possible for remote hospital or doctor to access PACS data and information easily and cheaply. The ASDCS uses receive-only satellite links for data delivery and PSTN (Public switched telephone Network) modem or N-ISDN (narrow band integrate services digital network) for communication. The satellite communication linking shows the very high-seed performance such as 10-30 times faster than the modem linking.To solve the speed limits of internet, JPEG and wavelet compression methods were adapted in WWW-based TelePACS and were evaluated by PSNR (peak signal-to-noise ratio) and by radiological experts that 10:1 or less JPEG and wavelet compression may be acceptable for diagnostic purposes. Consequently, we get the conslusion that our system is suitable for tele-radiology and telemedicine world widely.

• Archives of design research
• /
• v.14 no.1
• /
• pp.111-118
• /
• 2001

The primary purpose of this research is to identify effects of the complexity levels of visual factors on user's communication in the web-sites. In this study, six complexity levels of visual factors were manipulated with four items(graphics, moving graphics, size and links) to test communication effects. As a result, user's communication was influenced by the complexity of illustration. This result shows that web sites with moderate levels of illustration complexity are more preferred than with complex or simple levels of visual complexity.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2001.10b
• /
• pp.1057-1060
• /
• 2001

Web Security를 위한 방법으로서 anonymity에 대한 개념에 대해서 살펴보고, 멀티캐스트 그룹환경에서 web 보안을 위해 익명 서비스를 제공하는 anonymiser 를 사용하여 보다 효율적인 web 보안과 익명 서비스를 적용할 수 있는 방안을 제안 한다.

• Journal of information and communication convergence engineering
• /
• v.8 no.5
• /
• pp.473-478
• /
• 2010

Today's engineering design is carried out in a distributed fashion geographically or physically. This places new requirements on the computational environments such as efficient integration and collaboration. With the advances of the Internet and Network environment recently, many researches have been proposed and at the same time, Web-based distributed design gives to a new paradigm in design and manufacturing fields. That is, Web-based technologies lead to reduce the product development times and to ensure a competitive product in order to exchange and interact of real-time design information that integrates the distributed design environment between departments as well as companies via Internet and Web. So, an efficient data communication for design information sharing is the foundation for collaborative systems in the distributed environment. Design data communication techniques such as CORBA, DCOM and RMI have been considered in the existing research but they have some problems that are limitations of interoperability and firewall problems in the Web. Therefore, this paper presents a Web-based distributed design application where distributed design information resources are integrated and exchanged using Web Services for supporting XML and HTTP without the interoperability and firewall problems through the 330K VLCC case.

• Asia pacific journal of information systems
• /
• v.16 no.4
• /
• pp.179-202
• /
• 2006

The objective of this study is to identify the impacts of communication reinforcement on performance of learning in Web-PBL. Communication reinforcement is defined as the combination of information sharing and co-construction. As factors facilitating communication reinforcement, we propose learner's characteristics, task characteristics, and group characteristics. Learner's characteristics are collaboration-orientation, openness, holistic approach, and online community-orientation which reflects e-learning environment. Collaboration-oriented tasks as group projects were developed and given to groups with 5-6 members. The group characteristics are categorized into 'horizontal' and 'vertical', according to the patterns of communication between a group leader and members. To verify empirically the proposed research model, an experimental design was performed to learners who took on-line and off-line courses with group projects. We found important results as follows; First, field dependence has positive impacts on information sharing, and online community-orientation has positive impacts on co-construction. These results correspond with prior studies on relationship between field dependence and collaborative learning. Second, collaboration-oriented task directly impacts on information sharing, and indirectly affects co-construction, This result implicates that information sharing is pre-requisite of co-construction. Third, 'horizontal' was identified as a factor giving positive effects on information sharing and co-construction. This result implies that horizontal communication is very important to facilitate communication reinforcement.