• International Journal of Internet, Broadcasting and Communication
• /
• v.12 no.3
• /
• pp.9-17
• /
• 2020

In this paper, as part of the research for the infrastructure of very high flexible and reconfigurable data center using very high speed crossbar switches, we developed a simulator that can model two and three dimensional connection structure of switches with an efficient control algorithm using software defined network and verified the functions and analyzed the performance accordingly. The simulator consists of a control module and a switch module that was coded using Python language based on the Mininet and Ryu Openflow frameworks. The control module dynamically controls the operation of switching cells using a shortest multipath algorithm to calculate efficient paths adaptively between configurable computing resources. Performance analysis by using the simulator shows that the three-dimensional switch architecture can accommodate more hosts per port and has about 1.5 times more successful 1:n connections per port with the same number of switches than the two-dimensional architecture. Also simulation results show that connection length in a 3-dimensional way is shorter than that of 2-dimensional way and the unused switch ratio in a 3-dimensional case is lower than that of 2-dimensional cases.

• Journal of KIISE:Computing Practices and Letters
• /
• v.10 no.5
• /
• pp.375-384
• /
• 2004

The Grid is new infrastructure to provide computing environment for grand challenge research by sharing large-scale resources. Currently the Globus becomes a de facto standard middleware to construct Grid and supports core services such as resource management, security, data transfer, information services, and so on. However, it still needs more works and researches to satisfy requirements from various grid applications. A workflow management is becoming a main service as one of the important grid services for complex grid applications. We propose a Meta Scheduling Framework (MSF) in this paper. The MSF provides a XML-based Job Control Markup Language (JCML) for describing information and procedures of grid applications, and a workflow management service for scheduling the job using the JCML and for processing the job effectively.

• Journal of Internet Computing and Services
• /
• v.7 no.3
• /
• pp.31-39
• /
• 2006

Ubiquitous and pervasive environment presents opportunities for a rich set of location aware applications such as car navigation and intelligent robots, interactive virtual games, logistics service, asset tracking etc. Typical indoor location systems require better accuracy than what current outdoor location systems provide, Outdoor location technologies such as GPS have poor indoor performance because of the harsh nature of indoor environments, In this paper we present a novel reducing interference location system that is particularly well suited to support context aware computing. The system, called EEM (Enhance Envelop Method) alms to combine the advantages of real time tracking systems that implement distributed environment with the suitability of infrastructure sensor network.

• Journal of KIISE:Computing Practices and Letters
• /
• v.15 no.10
• /
• pp.715-723
• /
• 2009

The use of medical imaging in hospitals is being gradually increased as it is of utmost importance in treatment and diagnosis of patients. With the drastic increase of the usage of medical imaging in hospitals per day necessitates more speedy and accurate systems for precise diagnosis and the treatment. Hence the modality and development of network infrastructure are also need to be improved day by day and this trend may be continued. Thus there is a great need improvement of PACS concerned. In this paper, by using the computational grid technology, we design a medical image storage system that improve the compression speed, and implement a prototype as a part of PACS. We also demonstrate the performance improvement from experimental results of the prototype.

• Macromolecular Research
• /
• v.14 no.2
• /
• pp.140-145
• /
• 2006

E-science refers to the large-scale science that will increasingly be carried out through distributed global collaborations enabled by the Internet. The Grid is a service-oriented architecture proposed to provide access to very large data collections, very large scale computing resources and remote facilities. Web services, which are server applications, enable online access to service providers. Web portal interfaces can further hide the complexity of accessing facility's services. The main use of synchrotron radiation (SR) facilities by protein crystallographers is to collect the best possible diffraction data for reasonably well defined problems. Significant effort is therefore being made throughout the world to automate SR protein crystallography facilities so scientists can achieve high throughput, even if they are not expert in all the techniques. By applying the above technologies, the e-HTPX project, a distributed computing infrastructure, was designed to help scientists remotely plan, initiate and monitor experiments for protein crystallographic structure determination. A description of both the hardware and control software is given together in this paper.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.5 no.6
• /
• pp.595-601
• /
• 2010

Desktop virtualization technology running on the local computing system in the process of resource depletion or degradation, such as upgrading the system to solve problems and manage critical information and systems must be protected. In addition, a virtualized environment by constructing a convenient stand-virtualized infrastructure and user space, and security from external attack or internal flaw or a problem, even if the service fails to respond quickly and should help to recover. In this paper, a comprehensive virtualization technology based on the client's desktop virtualization technology elements needed to find a local computing environment more comfortable and stable in the proposed new virtualization technologies.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.3
• /
• pp.1014-1025
• /
• 2020

Cloud computing services changed the way the data are managed across the healthcare system that can improve patient care. Currently, most healthcare organizations are using cloud-based applications and related services to deliver better healthcare facilities. But architecting a cloud-based healthcare system needs deep knowledge about the working nature of these services and the requirements of the healthcare environment. The success is based on the usage of appropriate cloud services in the architecture to manage the data flow across the healthcare system.Cloud service providers offer a wide variety of services to ingest, store and process healthcare data securely. The top three public cloud providers- Amazon, Google, and Microsoft offers advanced cloud services for the solution that the healthcare industry is looking for. This article proposes a framework that can effectively utilize cloud services to handle the data flow among the various stages of the healthcare infrastructure. The useful cloud services for ingesting, storing and analyzing the healthcare data for the proposed framework, from the top three cloud providers are listed in this work. Finally, a cloud-based healthcare architecture using Amazon Cloud Services is constructed for reference.

• Journal of Korea Multimedia Society
• /
• v.23 no.2
• /
• pp.328-342
• /
• 2020

As the cloud-based ICT(Information & Communication Technology) infrastructure matures, the existing monolithic software development method is evolving into a micro-service structure based on cloud native computing. To develop and operate the services efficiently under the cloud native environment, DevOps-based application development plans through MSA(Micro Service Architecture) design based are essential. A cloud native environment is an approach to developing and running applications that take advantage of cloud computing models such as automation of source distribution, container-based virtualization, application scalability, resource efficiency, and flexible maintenance through object independence. To implement this approach, the utilization of key elements such as DevOps, continuous delivery, micro service, and containers is essential, but there are not enough previous studies on case analyses or application methods of these key elements. Therefore, in this paper, we analyze the cases of application development in cloud native environment and propose the optimized application development process and development method through small and medium-sized SI projects.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.8 no.4
• /
• pp.83-90
• /
• 2012

With the rapid growth of internet infrastructure, World Wide Web is evolving recently into various services such as cloud computing, social network services. It simply go beyond the sharing of information. It started to provide new services such as E-business, remote control or management, providing virtual services, and recently it is evolving into new services such as cloud computing and social network services. These kinds of communications through World Wide Web have been interested in and have developed user-centric customized services rather than providing provider-centric informations. In these environments, it is very important to check and analyze the user requests to a website. Especially, estimating user preferences is most important. For these reasons, analyzing web logs is being done, however, it has limitations that the most of data to analyze are based on page unit statistics. Therefore, it is not enough to evaluate user preferences only by statistics of specific page. Because recent main contents of web page design are being made of media files such as image files, and of dynamic pages utilizing the techniques of CSS, Div, iFrame etc. In this paper, large log analyzer was designed and executed to analyze web server log to estimate web contents preferences of users. With mapreduce which is based on Hadoop, large logs were analyzed and web contents preferences of media files such as image files, sounds and videos were estimated.

• Journal of the Korea Society of Computer and Information
• /
• v.12 no.1 s.45
• /
• pp.89-98
• /
• 2007

In these days, the use of context in application running on mobile devices such as PDAs and smart Phone has become a crucial requirement for several research areas, including ubiquitous computing. mobile computing. Previous middlewares which support context provisioning uses single strategy. But, this paper proposed middleware integrated multiple strategies for context provisioning, namely internal sensors-based, external infrastructure-based, and distributed provisioning in ad hoc networks. Applications can query needed context items using SQL like context query language and require context information to use different provisioning mechanisms depending on resource availability and presence of external infrastructures.