• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.5
• /
• pp.1005-1012
• /
• 2016

LED beacons operated on an isolated marine area are mostly employing the solar power supply system, and this system is well known for increasing the cost of management and maintenance. Recently, a number of researches and demonstrations on self-contained LED beacon is actively conducted to solve this issue. In this work, we propose an self-contained LED beacon with Bluetooth Low Energy function for an effective management of LED beacon. Firstly, control program structure is designed by expanding the status protocol of self-contained LED beacon, and then it is implemented into the form which administrator can easily understand. The control system visualizes the status and control data of self-contained LED beacon, and this enables the rapid decision-making of administrator. Also, minimizing electricity consumption of the beacon, it can transfer and update the status or light information of self-contained LED beacons with smart phone.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.4
• /
• pp.819-824
• /
• 2015

SDN (Software Defined Network) technology, hardware and network control functions should be separated independently of existing switches or routers and data transfer functions and are also refers to a separate network architecture that can develop and run. When planning a network and designed to reflect the network control function by applying the SDN may reflect the resources efficiently. In this study, one people suggest Applications SDN, which offer an absolutely necessary part of a coded program that combines the benefits of the existing IOS (Combined Benefits) applying the model to complete the Controller part through the MPLS IOS. The OpenFlow Controller is a command to the router LER(Label Edge Router), and transmits the packet in accordance with the command to the destination according to the EXP bit. To configure TCP / IP to the IOS through the optimized coding. Using the OpenFlow protocol controller transmits an encapsulation header as defined in the MPLS packet.

• The KIPS Transactions:PartC
• /
• v.12C no.6 s.102
• /
• pp.917-926
• /
• 2005

In this paper, we propose a transport layer mobility support protocol for multimedia streaming services in mobile/wireless environments by extending PR-SCTP to support mobility. We named the proposed scheme to be uPR-mSCTP. The rules related to provide unordered and unreliable data transfer, as well as an approach to minimize handover latency we proposed. Through the simulation results, it is shown that, since uPR-mSCTP reduces transmission rates during handover, not only it reduces the waste of network resources, but it also has the packet loss rate similar to FMIPv6, which is a lot smaller than UDP over MIPv6 or HMIPv6 It also incurs smaller control packet overhead compared to the network layer mobility support approaches.

• Smart Media Journal
• /
• v.9 no.3
• /
• pp.71-79
• /
• 2020

Mobile network is used by many users worldwide for diverse services, including phone-call, messaging and data transfer over the Internet. However, this network may experience massive damage if it is exposed to cyber-attacks or denial-of-service attacks via wireless communication interference. Because the mobile network is also used as an emergency network in cases of disaster, evaluation or verification for security and safety is necessary as an important nation-wide asset. However, it is not easy to analyze the mobile core network because it's built and serviced by private service providers, exclusively operated, and there is even no separate network for testing. Thus, in this paper, a virtual mobile network is built using OpenAirInterface, which is implemented based on 3GPP standards and provided as an open source software, and the structure and protocols of the core network are analyzed. In particular, the S1AP protocol messages captured on S1-MME, the interface between the base station eNodeB and the mobility manager MME, are analyzed to identify potential security threats by evaluating the effect of the messages sent from the user terminal UE to the mobile core network.

• Journal of the Korean Society for Library and Information Science
• /
• v.41 no.2
• /
• pp.359-386
• /
• 2007

This study is to develop the operation models collection and preservation of serials only distributed online. In order to identify all of the requisite items for collection and preservation of the online serials, it conducts Delphi Technique researches with panels of experts from public institutions, organizations, and research institutions. It also deduces the 68 necessary detailed items to develop the operation models for preserving the online serials, and suggests 57 detailed items selected from the compatibility analysis with the investigation and examination of compatibility and urgency. It suggests the automated collection plan of contents with the application of RSS technology of transfer protocol to provide users the updated information from the sites where the contents and data have been constantly and frequently updated. This study strives to design the collection and preservation processes suitable for the online serials.

• Journal of Internet Computing and Services
• /
• v.7 no.6
• /
• pp.87-103
• /
• 2006

Advances in computer and network technology provide new computing environment that were only possible with supercomputers before. In order to provide the environment, a distributed runtime system has to be provided, but most of the conventional distributed runtime systems lack in providing dynamic and flexible system reconfiguration depending on workload variance, due to a static architecture of fixed master node and slave working nodes. This paper proposes and implements a new model for distributed job allocation and management which is a distributed runtime system is P2P environment for flexible and dynamic system reconfiguration. The implemented systems enables job program transfer and management, remote compile and execution among cooperative developers based on P2P standard protocol Jxta platform. Since it makes dynamic and flexible system reconfiguration possible, the proposed method has some advantages in that it can collect and utilize idle computing resources immediately at a needed time for distributed job processing. Moreover, the implemented system's effectiveness and performance increase are shown by applying and processing the crawler jobs, in a distributed way, for collecting a large amount of data needed for internet search.

• Clinical and Experimental Reproductive Medicine
• /
• v.20 no.1
• /
• pp.37-43
• /
• 1993

In 27 patients with the past history of poor response to the gonadotropin superovulation induction due to poor follicular growth or permature surge of endogenous luteinizing hormone, the effectiveness of pituitary supperssion with the gonadotropin releasing hormone agonist(GnRH-a) in in vitro fertilization(IVF) program was evaluated in 43 cycles using a combination regimen of D-Trp-6 LHRH(Decapeptyl, Ferring)and FSH/hMG from June, 1989 to August, 1990 at Korea University Hospital IVF Clinic. At midluteal phase of menstrual cycle, Decapeptyl-CR was administered by long-term protocol to minimize initial agonistic effect of endogenous gonadotropins. After the confirmation of pituitary suppression, about 2-3 weeks after GNRH-a administration, ovarian follicle growth was stimulated with FSH/hMG and followed by transvaginal ultrasonic measurement of follicle size and by monitoring of serm E2 and LH if necessary. When compared with the control group stimulated with gonadotropin regimen only, the cancellation rate and occurrence rate of premature LH surge during gonadotropin treatment were significantly lower in study group(11.6% and 2.4%, respectively). There is no significant differences in the mean number of aspirated oocytes, fertilization/cleavage rate, embryo transfer(ET) rate, and mean number of embryos transferred between the two groups. The pregnancy rate per treatment cycle, 16.3%, and per ET cycle, 23.3%, were significantly higher in the study group compared with those of control group. These data suggest that GnRH-a therapy is effective for previous poor responder In gonadotropin superovulation induction for IVF.

• Journal of Digital Convergence
• /
• v.9 no.5
• /
• pp.225-233
• /
• 2011

Internet telephony is an Internet service which supports voice telephone using VoIP technology on the IP-based Internet. It has some advantages in that voice telephone services can be accompanied with multimedia services such as video communication and messaging services. Recently, the introduction of smart phones has led to a growth in social networking services and thus, the research and development of Internet telephony has been actively progressed and has the potential to become a replacement for the telephone service that is currently being used. In this paper we designed and implemented a recording system which records voice data of SIP-based Internet telephone's voice calls. It is developed on the linux system and has some features such as audio mixing of two in/out voice channels, live packet sniffing, and the ability to transfer mixed audio files to the log file server. These functions are implemented using various open source softwares. Afterwards, this VoIP recording system will be applied as a base technology to advanced services like a VoIP-based call center system.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39C no.11
• /
• pp.1167-1176
• /
• 2014

In this paper, a relay communication scheme for enhancing the WiMedia network performance by device's mobility is proposed. WiMedia protocol is suitable for the application that supports the real-time multimedia service in Ship Area Network since it supports high speed data transfer. However, the device's mobility is caused the dramatic change of link state and network topology, and is occurred the degradation of network performance. Therefore, a relay communication scheme for WiMedia network is proposed in this paper. The proposed technique can intelligently treat the change of link state, and solve the degradation of network performance.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.2
• /
• pp.305-311
• /
• 2010

iATA (Internet Advanced Technology Attachment) is a block-level protocol developed to transfer ATA commands over TCP/IP network, as an alternative network storage solution to address insufficient storage problem in mobile devices. This paper employs RAID5 distributed storage servers concept into iATA, in which the idea behind is to combine several machines with relatively inexpensive disk drives into a server array that works as a single virtual storage device, thus increasing the reliability and speed of operations. In the case of one machine failed, the server array will not destroy immediately but able to function in a degradation mode. Meanwhile, information can be easily recovered by using boolean exclusive OR (XOR) logical function with the bit information on the remaining machines. We perform I/O measurement and benchmark tool result indicates that additional fault tolerance feature does not delay read/write operations with reasonable file size ranged in 4KB-2MB, yet higher data integrity objective is achieved.