• The Journal of the Korea Contents Association
• /
• v.20 no.4
• /
• pp.396-405
• /
• 2020

In this study, we used the big data of Voice of Customer (VOC) related to high-speed Internet products to look at the causes of perceived quality and the possibility of proactive service. In order to verify the possibility of proactive service, we collected VOC data from 13 facilities and equipment of a mobile communication service company, and then conducted 𝒙² test to verify that there was a statistically significant difference between the actual VOC observation values and expected values. We found statistical evidence that proactive service is possible through real-time monitoring for the six disability alarms among the 13 facilities and equipment, which are FTTH-R Equipment ON/OFF, FTTH-EV Line Error Detection, Port Faulty, FTTH-R Line Error Detection, Network Loop Detection, and Abnormal Limiting Traffic. Companies are able to adopt the proactive service to improve their market share and to reduce customer service costs. The results of this study are expected to contribute to the actual application of industry in that it has diagnosed the possibility of proactive service in the telecommunication service sector and further suggested suggestions on how to provide effective proactive service.

• Journal of Digital Contents Society
• /
• v.17 no.6
• /
• pp.581-592
• /
• 2016

WebRTC has quickly grown to be the world's advanced real-time communication in several platforms such as web and mobile. In spite of the advantage, the current technology in WebRTC does not handle a big-streaming efficiently between peers and a large amount request of users on the Signaling server. Therefore, in this paper, we put our work to handle the problem by delivering the flow of data with dynamical load balancing algorithms. We analyze the request source users and direct those streaming requests to a load balancing component. More specifically, the component determines an amount of the requested resource and available resource on the response server, then it delivers streaming data to the requesting user parallel or alternately. To show how the method works, we firstly demonstrate the load-balancing algorithm by using a network simulation tool OPNET, then, we seek to implement the method into an Ubuntu server. In addition, we compare the result of our work and the original implementation of WebRTC, it shows that the method performs efficiently and dynamically than the origin.

• Journal of Broadcast Engineering
• /
• v.22 no.4
• /
• pp.484-495
• /
• 2017

The development of display devices and the increase of network transmission bandwidth bring demands for over 2K high resolution video such as panorama video, 4K ultra-high definition commercial broadcasting, and ultra-wide viewing video. To compress these image sequences with significant amount of data, High Efficiency Video Coding (HEVC) standard with the highest coding efficiency is a promising solution. HEVC, the latest video coding standard, provides high encoding efficiency using various advanced encoding tools, but it also requires significant amounts of computation complexity compared to previous coding standards. In particular, the complexity of HEVC decoding process is a imposing challenges on real-time playback of ultra-high resolution video. To accelerate the HEVC decoding process for ultra high resolution video, this paper introduces a data-level parallel video decoding method using slice and/or tile supported by HEVC. Moreover, deblocking filter process is further parallelized. The proposed method distributes independent decoding operations of each tile and/or each slice to multiple threads as well as deblocking filter operations. The experimental results show that the proposed method facilitates executions up to 2.0 times faster than the HEVC reference software for 4K videos.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.54 no.1
• /
• pp.55-69
• /
• 2017

Recently, the IoT (Internet of Things) environment is being developed rapidly through network which is linked to intellectual objects. Through the IoT, it is possible for human to intercommunicate with objects and objects to objects. Also, the IoT provides artificial intelligent service mixed with knowledge of situational awareness. One of the industries based on the IoT is a car industry. Nowadays, a self-driving vehicle which is not only fuel-efficient, smooth for traffic, but also puts top priority on eventual safety for humans became the most important conversation topic. Since several years ago, a research on the recognition of the surrounding environment for self-driving vehicles using sensors, lidar, camera, and radar techniques has been progressed actively. Currently, based on the WAVE (Wireless Access in Vehicular Environment), the research is being boosted by forming networking between vehicles, vehicle and infrastructures. In this paper, a research on the recognition of a traffic signs on highway was processed as a part of the awareness of the surrounding environment for self-driving vehicles. Through the traffic signs which have features of fixed standard and installation location, we provided a learning theory and a corresponding results of experiment about the way that a vehicle is aware of traffic signs and additional informations on it.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.25 no.5
• /
• pp.1123-1129
• /
• 2015

Macro(automatic hunting) of mobile game is a program that touch the screen by defined rules like a game bot in PC online games, and it is used by make various ways like android application or windows application program. This gives honest users deprivation and make to lose their interest. Finally they would leave the game and gradually game life would be shorten. Although many studies to prevent these problems in PC online game are conducted, applying mobile game to PC's way is difficult because mobile games are limited to use the network and device performance is different with PC. In this paper, we propose a framework for macro detection by using the touch event information. A touch event on the mobile game is a necessary control command to the game. Because macro touches the screen with the same pattern, there is a difference between normal user's behavior and macro's operation. In mobile games that casual games are mostly, Touch event is the best difference that identify normal user against macro for a short period of time. As a result of detecting macros used in real mobile game by using the proposed framework it showed 100% accuracy and 0% false positive rate.

• Journal of Bio-Environment Control
• /
• v.20 no.3
• /
• pp.169-175
• /
• 2011

The adaptive neuro-fuzzy inference system (ANFIS) based automatic control system framework was proposed for integrated environment management of ubiquitous plant factory which can collect information of crop cultivation environment and monitor it in real-time by using various environment sensors. Installed wireless sensor nodes, based on the sensor network, collect the growing condition's information such as temperature, humidity, $CO_2$, and the control system is to monitor the control devices by using ANFIS. The proposed automatic control system provides that users can control all equipments installed on the plant factory directly or remotely and the equipments can be controlled automatically when the measured values such as temperature, humidity, $CO_2$, and illuminance deviated from the decent criteria. In addition, the better quality of the agricultural products can be gained through the proposed automatic control system for plant factory.

• Journal of Korean Society of Transportation
• /
• v.19 no.3
• /
• pp.101-113
• /
• 2001

Since late 1970s. one of the principal research areas in transportation problem is dynamic traffic assignment (DTA). Although many models have been developed regarding DTA, yet they have some limits of describing real traffic patterns. This reason comes from the fact that DTA model has the time varying constraints such as state equation, flow propagation constraint, first in first out(FIFO) rule and queuing evolution. Thus, DTA model should be designed to satisfy these constraints as well as dynamic route choice condition, dynamic user equilibrium. In this respect, link-based DTA models have difficulty in satisfying such constraints because they have to satisfy the constraints for each link, while path-based DTA models may easily satisfy them. In this paper we develop a path-based DTA model. The model includes point queue theory to describe the queue evolution and simulation loading method for depicting traffic patterns in more detail. From a numerical test, the model shows promising results.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.11
• /
• pp.602-609
• /
• 2020

In the event of a large-scale disaster such as an earthquake, typhoon, landslide, and building collapse, the disaster situation awareness and timely disaster information sharing play a key role in the disaster response and decision-making stages for disaster management, such as disaster site control and evacuation of residents. In this paper, an exited field investigation system of NDMI (National Disaster Management Research Institute) was enhanced with an LTE-VPN- based wireless communication system to provide an effective on-site response in an urgent disaster situation and share observation data or analysis information acquired at the disaster fields in real-time. The required performance of wireless communication for the disaster field investigation system was then analyzed and evaluated. The experimental result for field data transmission performance of an advanced wireless communication investigation system showed that the UDP transmission performance of at least 4.1Mbps is required to ensure a seamless video conference system between disaster sites. In addition, a wireless communication bandwidth of approximately 10 Mbps should be guaranteed to smoothly share the communication and field data between the survey equipment currently mounted on the survey vehicle.

• The Journal of the Korea Contents Association
• /
• v.13 no.12
• /
• pp.575-584
• /
• 2013

Data types used for big-data analysis are very widely, such as news, blog, SNS, papers, patents, sensed data, and etc. Particularly, the utilization of web documents offering reliable data in real time is increasing gradually. And web crawlers that collect web documents automatically have grown in importance because big-data is being used in many different fields and web data are growing exponentially every year. However, existing web crawlers can't collect whole web documents in a web site because existing web crawlers collect web documents with only URLs included in web documents collected in some web sites. Also, existing web crawlers can collect web documents collected by other web crawlers already because information about web documents collected in each web crawler isn't efficiently managed between web crawlers. Therefore, this paper proposed a distributed web crawler. To resolve the problems of existing web crawler, the proposed web crawler collects web documents by RSS of each web site and Google search API. And the web crawler provides fast crawling performance by a client-server model based on RMI and NIO that minimize network traffic. Furthermore, the web crawler extracts core content from a web document by a keyword similarity comparison on tags included in a web documents. Finally, to verify the superiority of our web crawler, we compare our web crawler with existing web crawlers in various experiments.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.30 no.4
• /
• pp.413-422
• /
• 2012

After development of GPS in the 1960's, the United States released SA(Selective Availability) in 2000 and then the GPS has become commercialized to the present. The result of repeatedly developed GPS observation, the GPS real-time observation methods is RTK which basically always needs two base stations and has a fault of the accuracy decreasing as the distance between a mobile station and a receiver is increasing. Because of these weakness, VRS method has come out. VRS(Virtual Reference Station) generates the imaginary point near mobile station from several observatory datum of GPS, sets the accurate location of mobile station, thus shows high reliability and mobility. Now, the cadastral datum point is used with azimuth, repetition, and graphical traversing method for traverse network. The result of measurement indicates many problems because of different accomplishment interval given point, restrictions on the length of the conductor, many errors on the observations. So, this study did comparative analysis of the cadastral datum points through VRS method by Continuously Operating Reference Station. Through the above comparative analysis, The comparative result between surveyed result with repetition method through total station observed Cadastral Control Points and surveyed result with VRS-RTK has shown that average error of x-axis is -0.08m, average error of y-axis, +0.07m and average distance error is +0.11m.