• Title/Summary/Keyword: web-based control

Search Result 1,025, Processing Time 0.026 seconds

Load Control Mechanism for Real-Time Web Server Systems Based on Feedback Control Theory (피드백 제어 이론을 이용한 실시간 웹서버 시스템의 부하 제어 기법)

  • Kang, Bong-Jik;Jung, Suk-Yong;Kim, Young-Il;Choi, Kyung-Hee;Jung, Gi-Hyun;Yoo, Hae-Young
    • The KIPS Transactions:PartA
    • /
    • v.10A no.6
    • /
    • pp.615-626
    • /
    • 2003
  • This paper proposes a mechanism for managing overload Introduced by excessive web requests in real-time web service system. The many previous mechanisms statically manage the overload and thus the dynamic characteristics are not reflected. This paper proposes a mechanism that models system load based on control theory approach and includes its dynamic characteristics. We design a controller that is able to meet performance requirement. A feedback control system is implemented applying the proposed mechanism and the stable operation of system is verified through various simulation environments.

A Study on the Development of Web-based Full Motion Video E-mail System using MPEG-4 (웹을 기반으로 한 MPEG-4 동영상 E-mail 시스템의 개발)

  • 고재승
    • Journal of the Korea Computer Industry Society
    • /
    • v.3 no.3
    • /
    • pp.283-294
    • /
    • 2002
  • Now is the time for web-based video e-mail system because of world wide use of internet. But video data is so large, then data compression is much needed for transmission by web. In this paper, my colleagues and I implement full motion video e-mail system using MPEG-4, the international standards for audio-visual data. This video e-mail system is made of web-based active-X control, so easily accessible by web, and applies real-time audio-video compression. It's possible for everyone to send video e-mail for free to everywhere in the world if this system is used. The main application areas of this system are multimedia mailing service, web-based video advertisement, remote education, remote medical service and shopping mall construction, etc.

  • PDF

Automatic Extraction Method of Control Point Based on Geospatial Web Service (지리공간 웹 서비스 기반의 기준점 자동추출 기법 연구)

  • Lee, Young Rim
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.22 no.2
    • /
    • pp.17-24
    • /
    • 2014
  • This paper proposes an automatic extraction method of control point based on Geospatial Web Service. The proposed method consists of 3 steps. 1) The first step is to acquires reference data using the Geospatial Web Service. 2) The second step is to finds candidate control points in reference data and the target image by SURF algorithm. 3) By using RANSAC algorithm, the final step is to filters the correct matching points of candidate control points as final control points. By using the Geospatial Web Service, the proposed method increases operation convenience, and has the more extensible because of following the OGC Standard. The proposed method has been tested for SPOT-1, SPOT-5, IKONOS satellite images and has been used military standard data as reference data. The proposed method yielded a uniform accuracy under RMSE 5 pixel. The experimental results proved the capabilities of continuous improvement in accuracy depending on the resolution of target image, and showed the full potential of the proposed method for military purpose.

A Web GPS based Logistics Vehicle Control Management System using MVC Design Patterns (MVC 디자인 패턴을 활용한 Web GPS 기반의 물류차량 출하 관제 시스템)

  • Sim, Choon Bo;Kim, Kyoung Jong
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.6 no.1
    • /
    • pp.131-142
    • /
    • 2010
  • In this paper, we propose a web GPS based logistics vehicle control management system using MVC design patterns. The proposed system is designed by applying design patterns of object oriented modeling called mini-architecture to enhance reliability of software as well as promote stability of overall system design. In addition, we can get a position information by means of the GPS embedded in PDA and communicate between client and monitoring server using CDMA network so that the position of client can be identified directly by the map service. The system provides an moving object indexing technique which extends the existing TB-tree to manage and retrieve a transporting trajectory of logistics efficiently. Finally, with development of the logistics vehicle control service called WG-LOGICS system, we can verify the usefulness of our system which is able for monitoring a vehicle preparation, allocating registration, loading a burden, transfer path, and destination arrival in real world.

An Implementation of Image Security System Based on Web (웹기반 화상 감시 시스템의 구현)

  • Park Young-Seak;Cho Pyung-Kee
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.1 no.1
    • /
    • pp.74-81
    • /
    • 2000
  • In this paper we have developed an image security system based on Internet Web in order to overcome the problem of existing systems that use the dedicated network. The developed system resolves the safety problem of the centralized control model by adapting the distributed control model based on Web, and has the functions of remote control and automatic monitoring for grouped multiple sites on remote Web browser. And the system can operate various computers or operating system because it' s operating software was designed by the concepts of Java Virtual Machine and Virtual Instrument. Also, our system has not need of additional cost for network construction by using Internet and can greatly improve the managemental efficiency of system because the maintenance and publishing of software updates can be performed through Web Server.

  • PDF

Controller Design for Web Winding Process (웹재료의 와인딩 공정을 위한 제어기 설계)

  • 박기홍;허승진
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.20 no.5
    • /
    • pp.99-107
    • /
    • 2003
  • In a winding process, important control specifications include regulation of web tension and velocity. In this research, an adaptive controller has been developed for controlling web tension and velocity in winding processes. For the controller design, the linear quadratic regulator theory has been adopted and a gain-scheduling scheme has been incorporated. A prototype winding system has been constructed, and the controller has been implemented in a real-time PC-based environment. The performance of the closed loop system has been evaluated via simulation and experiments, and it was observed that both the web tension and velocity could be regulated within a small tolerance.

Effectiveness of Web-Based Learning in Basic Nursing Practice Education - focusing on Asepsis technique practice - (기본간호학 실습 교육에서 웹 기반 학습의 효과 - 무균술 실습교육을 중심으로 -)

  • Nam Mi-Ra
    • Journal of Korean Academy of Fundamentals of Nursing
    • /
    • v.12 no.3
    • /
    • pp.290-297
    • /
    • 2005
  • Purpose: This study was done to compare the effectiveness of web learning versus traditional education for learning Asepsis technique in Basic Nursing Practice. Method: This research was a quasi-experimental study. The participants were 60 students who were taking Basic Nursing at a nursing college in G city. Thirty students each were assigned to the experimental and the control group. Data were collected between September 26 and 30, 2005, The data were analyzed using descriptive statistics, Independent t-test and ANCOVA Results: The mean score for competence in Asepsis technique practice in the experimental group was 24.73 and in the control group 22.80. This result was statistically significant(t = 3.723, P = .001). The mean score for knowledge in the experimental group was 42.93 and in the control group 38.93. This result was statistically significant(t = 2.119, P = .038). The mean score for satisfaction with degree of study in the experimental group was 55.50 for the pre-test and 56.17 for the post-test, and in the control group 60.23 and 58.00 respectively. This result was statistically significant(F = 10.537, P = .002). Conclusion: The Web based learning was found to be effective in nursing practice, student satisfaction and knowledge, but web-based programs have to be continuously managed and various demands from learners have to be accepted. Eventually we have to use web-based program as educational medium to promote effective learning nursing education.

  • PDF

RCBAC(Relationship-Content based Access Control) Model for User Privacy Protection of Digital Contents in Web 2.0 Environment (웹 2.0 환경에서 사용되는 디지털 컨텐츠의 사용자 프라이버시 보호를 위한 RCBAC 모델)

  • Cho, Eun-Ae;Moon, Chang-Joo;Park, Dae-Ha;Kim, Jeong-Dong;Kang, Dong-Su;Baik, Doo-Kwon
    • Journal of Digital Contents Society
    • /
    • v.9 no.4
    • /
    • pp.697-705
    • /
    • 2008
  • The recent web technology has been developed by three mainsprings which include integration, virtualization, and socialization. The web technology provides the increment of the social networking ability. However it deepens the exposure of privacy about personal information as more complicating and difficult problems. Representatively, it is impossible to define and manage the specific relation, so the personal information and interest can be inferred from collecting and summarizing the contents. Also, there are some problems that it is hard to construct the information owner's own social network. Thus this paper proposes the RCBAC(Relationship-Content based Access Control) Model which applies both the concepts of Relationship and Content Semantic to the existing access control methods to protect the user's own digital contents in web 2.0 environment. This method prevents privacy such as personal inclination from being exposed and enables to define and manage the specific relation. By doing this the information owners can construct their social network. This social network can be applied and extended to web contents.

  • PDF

A Performance Isolation Mechanism Considering SLA in High Available Heterogeneous Cluster Web Systems (SLA를 고려한 클러스터 기반 고가용성 이질 웹 시스템의 성능 분리 기법)

  • Kang, Chang-Hoon;Park, Kie-Jin;Kim, Sung-Soo
    • The KIPS Transactions:PartA
    • /
    • v.12A no.7 s.97
    • /
    • pp.613-620
    • /
    • 2005
  • To provide reliable differentiated service for internet clients, many studies on differentiated service are widely done. According to the types of the request of the clients in cluster-based web systems, SLA (Service Level Agreement) between service provider and the clients is considered. In this Paper, we study primary-backup web switch in the web systems that distribute the request of clients to each of web servers and also study performance isolation and admission control schemes of heterogeneous web systems which distinguish the servers into each different function domains. We analyze the availability, the response time and the performance of admission control through various simulated experiments on the proposed web systems.

Protocol Implementations for Web Based Control Systems

  • Shoo Sugoog
    • International Journal of Control, Automation, and Systems
    • /
    • v.3 no.1
    • /
    • pp.122-129
    • /
    • 2005
  • We describe the MiniWeb[7] TCP/IP stack (mIP), which is an extremely small implementation of the TCP/IP protocol suite running 8 or 32-bit micro controllers intended for embedded control systems, and satisfying the subset of RFC1122 requirements needed for host­to-host interoperability over different platforms. Our TCP/IP implementation does sacrifice some of TCP's mechanisms such as fragmentation, urgent data, retransmission, or congestion control. Our implementation is applicable to web based controllers. The network protocols are tested in operational networks using CommView and Dummynet where the various operational parameters such as bandwidth, delay, and queue sizes can be set and controlled.