• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.12
• /
• pp.2852-2859
• /
• 1997

Video-On-Demand system provides electronic video rental services from remote video servers on a broadband communication networks. Most of proposed VOD systems are typically designed for one-to-one conncetion between a user and video server. Therefore, video server stream services to customers individually by allocating a dedicated transmission channel and a set of video server resources for each customer. However, it is inefficiency and wxpensive way when server support multiple users who access the same video stream with a dedicated video channel. Therefore, to achieve cost-effectiveness, batching have studied method that uses multicast communication to simultaneously service all users requesting the same video with a single video with a single video stream. However, the application of the multicast communication by batching detract from the VCR-like function and on-demand nature of the system. In this paepr, we propose a scheme that can support an interactive VCR for all user requesting the same video stream with batching. To reduce a server I/O and network bandwidth requirement, dynamic buffer is allocated to access node which has variable playout poit. Consequently, it makes possible interactive VCR operation as if customer uses true VOD system. Also, this scheme can just deliver a multicast stream without delay after an initial request or VCR action occurred. The policy can guarantee acceptable services to number of users at minimum cost.

• The KIPS Transactions:PartA
• /
• v.10A no.6
• /
• pp.595-604
• /
• 2003

A Digital TV system is necessary for data Processing as well as video and audio processing. Especially in the case of interactive broadcasting, it should manage returning channel created by the Internet, PSTN, and so on. Because of many functionalities and multitasking jobs, it needs an Operating System. Embedded Linux as open source program can increase a cost effectiveness in market and has many advantages - reusable device drivers and application programs, more convenient developing environment using shell and file system, and easy problem resolution within Open Source Community. In this paper, we modified Embedded Linux kernel and cross developing environment for a big-endian system, redesigned devices for kernel execution, and configured system memory map in order to load a linux kernel. Also we developed an device driver for entire system control.

• Korean journal of communication and information
• /
• v.39
• /
• pp.102-139
• /
• 2007

This research studied how political online discussion participation and experiencing opinion disagreement during the discussion affect on civic attitudes(interpersonal trust and reciprocity) and civic participation through pretest-posttest control group experimental treatment. For results, first of all, online political discussion positively affects on civic attitude of participants, but it's effect was partial. Next, experiencing opinion disagreement can help to have rather improving civic attitude than reducing civic attitude. Finally, civic attitude consists of interpersonal trust and reciprocity acquired from online discussion also partially and positively affects on civic participation which is more affected by reciprocity than interpersonal trust. Regard to these effect of online discussion, civic attitude can be extended by participating political communication(discussion), and participating communicative associations lead to encourage civic attitude of them and function to reinforce social integration and social ties.

• Journal of Information Technology Application
• /
• v.3 no.1
• /
• pp.1-21
• /
• 2001

The explosive growth of the Internet and the increasing popularity of the World Wide Web have generated significant interest in the development of electronic commerce in a global online marketplace. The rapid adoption of the Internet as a commercial medium is rapidly expanding the necessity of Web advertisement as a new communication channel. if proper Web advertisement could be suggested to the right user, then effectiveness of Web advertisement will be raised and it will help company to earn more profit. So, this article describes a personalized advertisement technique as a part of intelligent customer services for an electronic newspaper provide. Based on customers history of navigation on the electronic newspapers pages, which are divided into several sections such as politics, economics, sports, culture, and so on, appropriate advertisements (especially, banner ads) are chosen and displayed with the aid of machine learning techniques, when customers visit to the site. To verify feasibility of the technique, an application will be made to one of the most popular e-newspaper publishing company in Korea.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2014.02a
• /
• pp.340.2-340.2
• /
• 2014

최근 비정질 산화물 반도체는 가시광 영역에서의 투명도와 낮은 공정 온도, 그리고 높은 Field-effect mobility로 인해 Thin film transistors의 Active channel layer의 재료로 각광 받고 있다. ZnO, IZO, IGO, ITGO등의 많은 산화물 반도체들이 TFT의 채널층으로의 적용을 위해 활발히 연구되고 있으며, 특히 비정질 IGZO는 비정질임에도 불구하고 Mobility가 $10cm^2/Vs$ 정도로 기존의 a-Si:H 보다 높은 Mobility 특성을 나타내고 있어 대화면 디스플레이와 고속 구동을 위한 LCD에 적용 할 수 있으며 또한 낮은 공정 온도로 인해 플렉서블 디스플레이에 응용될 수 있다는 장점이 있다. 우리는 RF magnetron sputtering법으로 증착한 비정질 IGZO TFT(Thin Film Transistors)의 전기적 특성과 IGZO 박막의 특성에 미치는 RF power의 영향을 연구하였다. 제작한 TFTs의 Active channel layer는 산소분압 1%, Room temperature에서 RF power별(50~150 W)로 Si wafer 기판 위에 30nm로 증착 하였고 100 nm의 $SiO_2$가 절연체로 사용되었다. 또한 박막 특성을 분석하기 위해 같은 Chamber 분위기에서 100 nm로 IGZO 박막을 증착하였다. 비정질 IGZO 박막의 X-ray reflectivity(XRR)을 분석한 결과 RF Power가 50 W에서 150 W로 증가 할수록 박막의 Roughness는 22.7 (${\AA}$)에서 6.5 (${\AA}$)로 감소하고 Density는 5.9 ($g/cm^3$)에서 6.1 ($g/cm^3$)까지 증가하는 경향을 보였다. 또한 제작한 IGZO TFTs는 증착 RF Power가 증가함에 따라 Threshold voltage (VTH)가 0.3~4(V)로 증가하는 경향을 나타내고 Filed-effect mobility도 6.2~19 ($cm^2/Vs$)까지 증가하는 경향을 보인다. 또한 on/off ratio는 모두 > $10^6$의 값을 나타내며 subthreshold slope (SS)는 0.3~0.8 (V/decade)의 값을 나타낸다.

• Journal of Internet Computing and Services
• /
• v.4 no.1
• /
• pp.53-65
• /
• 2003

I/O processing speed of relatively sluggish storage devices incurs overall performance degradation in computer systems. As a solution to improve the situation, SAN(Storage Area Network) has been proposed. In order to utilize a SAN system more effectively, where storage devices are directly connected with a high speed network such as Fibre Channel, a proper management tool is needed. In this paper, we present a design and implementation of a performance monitoring and configuration management tool for the SANtopia system which supports global file sharing in the SAN environment The developed tool is to monitor the performance of the Linux hosts composing the SANtopia system and to manage the configuration of the hosts and storage devices. It also supports GUI(Graphic User Interface) environment using the JAVA programming language.

• The Journal of the Convergence on Culture Technology
• /
• v.5 no.4
• /
• pp.209-215
• /
• 2019

The purpose of this study is to suggest the development of interactive services and technologies in the media industry. Through the analysis of domestic two-way broadcasting contents service, this study analyzed platform and services type according to service type of terrestrial broadcasting, SO operator and Telco. Also, by identifying the characteristics of interactive programs(open, interactive, personalized, stereoscopic), this study propose important convergence possibilities of the future providers and development plans through supporting technologies and services for each characteristic. In the case of terrestrial broadcasters, ARS, web sites and mobile apps were mostly provided in both directions, and SO and satellite broadcasting operators were found to provide diversity in interactive service operation using data domain. In the case of IPTV companies, most of them provide interactive services with additional video or information service through adjustment button or app, and cable TV operators had more adjustment data broadcasting than exclusive use data broadcasts. Therefore, domestic interactive broadcasting service type needs convergence type of revenue model needs and needs to be converted into new competitive interactive broadcasting program service environment.

• Economic and Environmental Geology
• /
• v.36 no.2
• /
• pp.123-131
• /
• 2003

Geophysical surveys(electrical resistivity, self-potential, seismic refraction, GPR) were conducted to investigate the physical properties of the subsurface, and to delineate the flow channel of leachate from a AMD(acid mine drainage), buried rock wastes and tailings, and drainage pipes at an abandoned mine(Kwangyang mine). Especially in rainy season the sites appear to be abundant in AMD leachate, characterized by electrical conductivities of 0.98-1.10 ms/S. Electrical resistivity sections indicate that the leachate flows running in two directions at southern part rise up through the narrow fracture zones at the central part and contaminates the surrounding soil and stream. Such schematic features at the anomalous zone are well correlated with negative peaks in self-potential data, the limited penetration depth in GPR data and low velocity zone in seismic refraction data. Shallow high-resistivity zone is associated with the buried rock wastes which cause the diffractions in GPR image. In addition, the events at depth of approximately 1-1.25 m in GPR sections must be the metal pipes through which AMD is drained off to the inner bay.

• Journal of Broadcast Engineering
• /
• v.13 no.6
• /
• pp.941-950
• /
• 2008

The quality of projector output image is influenced by the surrounding conditions such as the shape and color of screen, and environmental light. Therefore, techniques that ensure desirable image quality, regardless of such surrounding conditions, have been in demand and are being steadily developed. Among the techniques, radiometric compensation is a representative one. In general, radiometric compensation is achieved by measuring the color of the screen and environmental light based on an analysis of camera image of projector output image and then adjusting the color of projector input image in a pixel-wise manner. This process is not time-consuming for small sizes of images but the speed of the process drops linearly with respect to image size. In large sizes of images, therefore, reducing the time required for performing the process becomes a critical problem. Therefore, this paper proposes a fast radiometric compensation method. The method uses color filters for eliminating the color mixing between projector and camera because the speed of radiometric compensation depends mainly on measuring color mixing between projector and camera. By using color filters, there is no need to measure the color mixing. Through experiments, the proposed method improved the compensation speed by 44 percent while maintaining the projector output image quality. This method is expected to be a key technique for widespread use of projectors for large-scale and high-quality display.

• Journal of dental hygiene science
• /
• v.4 no.2
• /
• pp.61-73
• /
• 2004

In this study, I have analyzed domestic dental clinics which had introduced CRM for customer satisfaction management. The purpose of this study is to provide information for designing efficient CRM. I would suggest some strategies to carry out CRM as followed. First, promote long-term relationship with customers. Second, select a target patient group and classify customers. Third, set a systematic database up. Fourth, make various channels to communicate with customers. In addition, the following ways are essential to be successful in implementing CRM. First, strengthen the service provided at the Moment of Truth (MOT). Second, organize learning in hospital and all the staff should be customer-oriented. Third, perform systematic "internal marketing".