• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2017.11a
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• pp.79-81
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• 2017

최근 오디오 기반의 그룹 대화 통신 기술이 급격히 발전하고 있는데 이는 원거리 간의 회의 또는 긴급 구조망, 음성 인식을 활용한 기술 분야에서 필요로 하기 때문이다. 과거 오디오 그룹 간의 실시간 서비스는 영상 통신보다 타이밍에 있어서 사용자에게 딜레이 되는 값을 전송하는 즉 버퍼 컨트롤이 문제가 되어 잘 사용되지 않았었다. 하지만 최근 다중경로 라우팅, QoS 전송량 감소 기술들이 소개되면서 N:N의 대화가 가능하게 되었다. 본 연구에서는 UDP Socket 방식을 활용하여 N:N 실시간 음성 서비스를 개발한다. 이는 무선단말기를 활용하여 3~4인이 그룹핑 되어 노래 경쟁을 할 수 있는 앱에 적용하여 개발하였다. 운전자가 혼자 운전할 때, 다른 지역에서 운전하는 사람들과 음성인식 인터페이스를 활용하여 즉각적인 그룹을 만들고, 자신과 다른 사람들이 노래를 부르고, 듣고 평가하는 과정에서 재미를 느끼게 함으로써 졸음을 방지할 수 있도록 개발하였다.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.6
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• pp.1045-1054
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• 2020

In this paper, we designed a TCP/IP based ring buffer system that can stably transfer bulk data streams in the unstable network environments. In the scheme we proposed, The observation data stream generated and output by each radio observatory's backend system as a UDP frame is stored as a UDP packet in a large capacity ring buffer via a socket buffer in the client system. Thereafter, for stable transmission to the remote destination, the packets are processed in TCP and transmitted to the socket buffer of server system in the correlation center, which packets are stored in a large capacity ring buffer if there is no problem with the packets. In case of errors such as loss, duplication, and out of order delivery, the packets are retransmitted through TCP flow control, and we guaranteed that the reliability of data arriving at the correlation center. When congestion avoidance occurs due to network performance instability, we also suggest that performance degradation can be minimized by applying parallel streams.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10a
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• pp.119-123
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• 2006

컴퓨터와 하드웨어의 발달과 더불어 데이터 통신기술은 인터넷을 필두로 하여 괄목할만한 발전을 가져왔다. 아울러 FTP, Telnet, SMTP, HTTP, DHCP등의 네트워크 응용 프로토콜도 속도와 유저 인터페이스에 있어서 수많은 변화가 있었다. 하지만 이러한 외형적인 변화에도 불구하고 TCP, UDP 방식의 Socket 프로토콜은 네트워크 프로그래밍의 가장 기초적인 원리를 제시하고 있는데, 초보 학습자들에게 있어서 Socket을 구성하는 많은 시스템 함수들을 모두 이해하고 이것을 프로그래밍에 적용하기란 쉬운 일이 아니다. 본 연구에서는 Socket의 많은 함수들을 API기반의 모듈로 캡슐화 하여 C/C++ 기반의 네트워크 프로그래밍을 보다 손쉽고 효율적으로 수행할 수 있고, 또한 네트워크 프로그래밍의 동작 원리를 효과적으로 프로그래밍 학습에 적용할 수 있는 전산 교육시스템인 네트워크 프로그램 소스 생성기를 제안 한다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2019.07a
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• pp.245-246
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• 2019

본 논문에서는 GUI(Graphical User Interface)를 이용하여 다수의 드론을 동시 제어하는 시스템 구현 결과를 보인다. 네트워크 소켓(Network Socket) 응용 프로그램인 Packet Sender를 이용하여 다수의 드론을 AP(Wireless Access Point)에 연결하였다. Python 응용 프로그램으로 UDP(User Datagram Protocol) 소켓을 통해 AP에 연동된 드론으로 명령을 전송하여 제어한다. Python GUI 모듈인 Tkinter를 이용하여 사용자에게 GUI를 제공함으로써 접근성(Accessibility)을 높인 시스템을 개발하였다.

• IEMEK Journal of Embedded Systems and Applications
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• v.17 no.3
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• pp.185-190
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• 2022

We propose a high speed data communication method for motor drive systems with fast control cycle in order to collect state variables of motor control without degrading control performance. Ethernet is chosen for communication device, and multi-core DSP architecture is exploited for communication processing load distribution. The communication program including network protocol stack and motor control program are assigned to two separate cores, and data between two cores are exchanged using interrupt-based inter-process communication mechanism, which enables to achieve a high-speed communication performance without degrading the motor control performance. The performance of developed communication method is demonstrated by real experiments using TCP, UDP and Raw Socket protocols in an experimental setup consisting of TI's TMS320F28388D motor control card and MS Windows PC.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.737-740
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• 1998

Under the worldwide booming internet environment, there has been increasing demand for various multimedia services. Especially the demand for effective video services has been rapidly increased. In this paper, we describe the implementation of video service system for internet use based on H/263 video compression technique and UDP socket on the TCP/IP environment. In addition, by using the plug-in-play technique, the implemented system improved user interface for correct retrieval and easy usage.

• KIPS Transactions on Computer and Communication Systems
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• v.7 no.1
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• pp.19-26
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• 2018

Recently, DDoS amplification attacks using servers that provide Microsoft Active Directory information using CLDAP protocol are increasing. Because CLDAP is an open standard application that allows a wide range of directory information to be accessed and maintained in a network, the server is characterized by its openness to the Internet. This can be exploited by the Reflector server to perform an amplification attack by an attacker. In addition, this attack can be attacked with a packet that is amplified 70 times more than the conventional UDP-based flooding attack, and it can block service to small and medium sized server. Therefore, in this paper, we propose an algorithm that can reduce the DDoS amplification attack using CLDAP server and implement the corresponding CLDAP server environment virtually, and implement and demonstrate the corresponding algorithm. This provides a way to ensure the availability of the server.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.1
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• pp.78-85
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• 2014

The Mu-communication board supported by hybrid communication is designed with Cortex M3, which is a low power energy consumption 32-bit microcontroller. The Cortex M3 microcontroller has UART(Universal asynchronous receiver/transmitter) ports which can set appropriately using the command line interpreter (CLI) program with each port. URAT ports are used for hybrid communication modems, GPS modules, etc. When the socket type was compared with the short message service type, the socket type was proven to be better. By improving the receiving performance in the control and management system of the AtoN, data loss was minimized. During the testing of the socket and SMS, data was collected from each buoy for 12 hours every 1 minute and the receiving rate of the data was found to be more than 98.58 % and 99.42 % respectively.

• Journal of Internet Computing and Services
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• v.3 no.1
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• pp.81-90
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• 2002

Large-scale distributed applications based on Internet and client/server applications have to deal with series of problems. Load balancing, unpredictable communication delays, and networking failures can be the example of the series of problems. Therefore. sophisticated applications such as teleconferencing, video-on-demand, and concurrent software engineering require an abstracted group communication, CORBA does not address these paradigms adequately. It mainly deals with point-to-point communication and does not support the development of reliable applications that include predictable behavior in distributed systems. In this paper, we present our design, implementation and performance analysis of the group communication using the CORBA-ORB. JAVA-RML and Socket based on distributed computing Performance analysis will be estimated latency-lime according to object increment, in case of group communication using ORB of CORBA the average is 14.5172msec, in case of group communication using RMI of Java the average is 21.4085msec, in case of group communication using socket the average is becoming 18.0714msec. Each group communication using multicast and UDP can be estimated 0.2735msec and 0.2157msec. The performance of the CORBA-ORB group communication is increased because of the increased object by the result of this research. This study can be applied to the fault-tolerant client/server system, group-ware. text retrieval system, and financial information systems.

• Journal of Convergence for Information Technology
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• v.10 no.6
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• pp.140-146
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• 2020

Since the current crime prevention systems have a standard mechanism that victims request for help by themselves or ask for help from a third party nearby, it is difficult to obtain appropriate help in situations where a prompt response is not possible. In this study, we proposed and developed an automatic rescue request model and system using Deep Learning and OpenCV. This study is based on the prerequisite that immediate and precise threat detection is essential to ensure the user's safety. We validated and verified that the system identified by more than 99% of the object's accuracy to ensure the user's safety, and it took only three seconds to complete all necessary algorithms. We plan to collect various types of threats and a large amount of data to reinforce the system's capabilities so that the system can recognize and deal with all dangerous situations, including various threats and unpredictable cases.