• Title/Summary/Keyword: polling

Search Result 263, Processing Time 0.035 seconds

An Information Transmission Method of DC Switch Gear for Light Railway Vehicle using Communication Network (통신망을 이용한 경량전철용 직류배전반의 정보 전송방식)

  • Lee H.D.;Jeon Y.J.;Kim S.N.;Baek B.S.;Ryu S.P.;Seo K.D.
    • Proceedings of the KIEE Conference
    • /
    • summer
    • /
    • pp.953-955
    • /
    • 2004
  • This paper describes the information transmission method using communication networks between Remote Terminal Unit(RTU) and Protection and Control system(PCU) of the direct current switchgear for Light Railway Vehicle, and also represents the test result, which carried out in the laboratory. In this test, transmission signal waveform, polling time, response time and request/response frame were measured between RTU and PCU. The field test including the measurements of analog signal and status of the digital logic operation of PCU will be conducted in near future.

  • PDF

Design of an efficient learning-based face detection system (학습기반 효율적인 얼굴 검출 시스템 설계)

  • Kim Hyunsik;Kim Wantae;Park Byungjoon
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.19 no.3
    • /
    • pp.213-220
    • /
    • 2023
  • Face recognition is a very important process in video monitoring and is a type of biometric technology. It is mainly used for identification and security purposes, such as ID cards, licenses, and passports. The recognition process has many variables and is complex, so development has been slow. In this paper, we proposed a face recognition method using CNN, which has been re-examined due to the recent development of computers and algorithms, and compared with the feature comparison method, which is an existing face recognition algorithm, to verify performance. The proposed face search method is divided into a face region extraction step and a learning step. For learning, face images were standardized to 50×50 pixels, and learning was conducted while minimizing unnecessary nodes. In this paper, convolution and polling-based techniques, which are one of the deep learning technologies, were used for learning, and 1,000 face images were randomly selected from among 7,000 images of Caltech, and as a result of inspection, the final recognition rate was 98%.

Political Regionalism in Korean Congressional Elections 1988$\sim$2004: A case study with provincial border regions Yeongdong, Muju and Kimcheon (총선으로 본 지역주의 -영동.무주.김천 지역을 중심으로-)

  • Kim, Jai-Han
    • Journal of the Korean association of regional geographers
    • /
    • v.13 no.4
    • /
    • pp.381-395
    • /
    • 2007
  • After the democratization process since 1988, the national scale voting behavior in congressional elections has changed from a rural-government party and urban-opposite party connection to a political regionalism oriented pattern. In this context, the case study with provincial border regions aims to investigate possible party identification change of the region, and to find a relationship between polling score ratio and socio-political characteristics of the candidates. As a result, Yeongdong shows a strong negation to the presumed Chungcheong local party and shows a continuous party identification with the Kyungsang local party. Muju reveals a more or less weakened identification with the Jeolla local party, on the contrary, Kimcheon shows a unchanged strong identification with the Kyungsang local party. The regional neighborhood effect was verified quite partly between the subdivision districts of the border regions. With a application of linear fitting method, it is certified that voters have attached great importance to the belonging party, native place, as well as political career of the candidates as a voting criterion.

  • PDF

Design and Development of Network for Housing Estate Security System

  • Nachin, Awacharin;Mitatha, Somsak;Dejhan, Kobchai;Kirdpipat, Patchanon;Miyanaga, Yoshikazu
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2003.10a
    • /
    • pp.1480-1484
    • /
    • 2003
  • This paper presents the design and development of network for housing estate security system. The system can cover up to 961 houses which can be up to 1,200 meters long transfer rate of 9,600 bps. This system uses checking and warning the abnormal situation. More over this system has ability to control switch on/off the electrical equipment in the house via AC line control system. The system consists of 4 parts. The first part is a security system of each house using MCS-51 microcontroller as a central processing unit scan 32 sensors and control 8 appliances and send alarm. The MCS-51 microcontroller received control signal via telephone used DTMF circuit. The second part is distributed two levels master/slave network implementing after RS-485 serial communication standard. The protocol its base on the OSI (Open Systems Interconnection) 7 layers protocol model design focus on speed, reliability and security of data that is transferred. The network security using encrypt by DES algorithm, message sequence, time stamp checking and authentication system when user to access and when connect new device to this system. Flow control in system is Poll/Select and Stop-and-Wait method. The third part is central server that using microcomputer which its main function are storing event data into database and can check history event. The final part is internet system which users can access their own homes via the Internet. This web service is based on a combination of SOAP, HTTP and TCP/IP protocols. Messages are exchanged using XML format [6]. In order to save the number of IP address, the system uses 1 IP address for the whole village in which all homes and appliance in this village are addressed using internal identification numbers. This proposed system gives the data transfer accuracy over 99.8% and maximum polling time is 1,120 ms.

  • PDF

Development of Vehicle LDW Application Service using AUTOSAR Platform on Multi-Core MCU (멀티코어 상의 AUTOSAR 플랫폼을 활용한 차량용 LDW 응용 서비스 개발)

  • Park, Mi-Ryong;Kim, Dongwon
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.14 no.4
    • /
    • pp.113-120
    • /
    • 2014
  • In this paper, we examine Asymmetric Multi-Processing Environment to provide LDW service. Asymmetric Multi-Processing Environment consists of high-speed MCU to support rapid image processing and low-speed MCU for controlling with other ECU at the control domain. Also we designed rapid image process application and LDW application Software Component(SW-C) according to the development process rule of AUTOSAR. To communicate between two MCUs, timer based polling based IPC was designed. Also to communicate with other ECUs(Electronic Control Units), we designed CAN messages to provide alarm information and receiving CAN message to catch the Turn signal. We confirm the possibility of the various ADAS development using an Asymmetric Multi-Processing Environment and AUTOSAR platform. We also expect providing ISO 26262 functional safety.

Modelling of Differentiated Bandwidth Requests in IEEE 802.16m Systems

  • Yoon, Kang Jin;Kim, Ronny Yongho;Kim, Young Yong
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.7 no.4
    • /
    • pp.726-747
    • /
    • 2013
  • In order to support a large number of mobile stations (MSs) with statistical multiplexing in cellular networks, a random access scheme is widely used for uplink (UL) bandwidth request (BR). In the design of a random access based BR scheme, there are two important requirements: short connection delay and diverse Quality of Services (QoSs) support. Such requirements are crucial for IMT-Advanced systems like IEEE 802.16m to provide various types of fourth generation (4G) data services. IEEE 802.16m provides advanced UL BR schemes for non-real time polling service (nrtPS) and best-effort (BE) service to meet the requirements of short connection time and multiple QoS level support. In order to provide short connection time and multiple QoS support, three-step and differentiated BR procedures are adopted. In this paper, a novel modelling of IEEE 802.16m contention based BR scheme is proposed that uses a 2-dimensional discrete time Markov chain. Both the short access delay three-step BR procedures and normal five-step BR procedure are considered in the model. Our proposed model also incorporates the IEEE 802.16m differentiated BR procedure. With the proposed model, we extensively evaluate the performance of IEEE 802.16m BR for two different service classes by changing QoS parameters, such as backoff window size and BR timer. Computer simulations are performed to corroborate the accuracy of the proposed model for various operation scenarios. With the proposed model, accurate QoS parameter values can be derived for the IEEE 802.16m contention-based BR scheme.

A Study on an Improvement of Network Monitoring Performance by Adding Time Variables in SNMP PDU (SNMP PDU의 시간변수 추가를 통한 네트워크 모니터링 성능 향상에 관한 연구)

  • 윤천균;정일용
    • Journal of Korea Multimedia Society
    • /
    • v.6 no.7
    • /
    • pp.1266-1276
    • /
    • 2003
  • Multimedia information containing voice and image is transmitted on Internet, which is ten times or hundred times larger than ordinary information. Analysis types for network management in this environment consist of a real time analysis, a basic analysis and an intensive analysis. The intensive analysis is useful for gathering the trend information of specific objects periodically for certain period in order to monitor network status. When SNMP is applied to collect the trend information of intensive analysis, it brings on the increase of network load, the delay of response time and the decrease of data collection accuracy since an agent responds to manager's every polling. In this paper, an efficient SNMP is proposed and implemented to add time variables in the existing SNMP PDU. It minimizes unnecessary traffic in the intensive analysis between manager and agent, and collects trend information more accurately. The results of experiments show that it has compatibility with the existing SNMP, decreases the amount of network traffic greatly and increases the accuracy of data collection.

  • PDF

Service Class Priority Controlled DBA Scheduling Method and Performance Evaluation in Ethernet PONs (Ethernet PONs에서 서비스 클래스별 전송 우선순위를 적용한 DBA 스케쥴링 방식 및 성능 분석)

  • Nam Yoon-Seok
    • The KIPS Transactions:PartC
    • /
    • v.12C no.5 s.101
    • /
    • pp.679-686
    • /
    • 2005
  • Because EPON access network shares a medium and aggregates the traffic from EPON subscribers, scheduling media access control on EPON bandwidth allocation is very important. Furthermore DBA mechanism of EPON based on TDMA is out of specification and up to implementation. This paper deals with a DBA method to guarantee the QoS of the delay sensitive traffic on the base of best-effort service and delay priority queue management. The proposed method performs virtual scheduling algorithm for the integrated traffic. It uses the same MAC messages and tries to guarantee the QoS of higher priority traffic first with a simple DBA architecture. We evaluate the algorithm for traffic delay according to polling interval and traffic load of upstream and downstream. The results show that the proposed method can guarantee the QoS of the delay sensitive traffic with priority of the service classes.

A Study on the Theme Park Users' Choice behavior -Application of Constraints-Induced Conjoint Choice Model- (주제공원 이용자들의 선택행동 연구 -Constraints-Induced Conjoint Choice Model의 적용-)

  • 홍성권;이용훈
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.28 no.2
    • /
    • pp.18-27
    • /
    • 2000
  • The importance of constraints has been one of major issues in recreation for prediction of choice behavior; however, traditional conjoint choice model did not consider the effects of these variables or fail to integrate them into choice model adequately. The purposes of this research are (a) to estimate the effects of constraints in theme park choice behavior by the constraints-induced conjoint choice model, and (b) to test additional explanatory power of the additional constraints in this suggested model against the more parsimonious traditional model. A leading polling agency was employed to select respondents. Both alternative generating and choice set generating fractional factorial design were conducted to meet the necessary and sufficient conditions for calibration of the constraints-induced conjoint choice model. Th alternative-specific model was calibrated. The log-likelihood ratio test revealed that suggested model was accepted in the favor of the traditional model, and the goodness-of-fit($\rho$$^2$) of suggested and traditional model was 0.48427 and 0.47950, respectively. There was no difference between traditional and suggested model in estimates of attribute levels of car and shuttle bus because alternatives were created to estimate the effects of constraints independently from mode related variables. Most parameters values of constraints had the expected sign and magnitude: the results reflected the characteristics of the theme parks, such as abundance of natural attractions and poor accessibility in Everland, location of major fun rides indoor in Lotte World, city park like characteristics of Dream Land, and traffic jams in Seoul. Instead of the multinomial logit model, the nested logit model is recommended for future researches because this model more reasonably reflects the real decision-making process in park choice. Development of new methodology too integrate this hierarchical decision-making into choice model is anticipated.

  • PDF

A New Bandwidth Allocation Scheme for Hard Real-time Communication on Dual IEEE 802.11 WLANs (이중 IEEE 802.11 WLAN에서 경성 실시간 통신을 위한 대역폭 할당)

  • Lee, Jung-Hoon;Kang, Mi-Kyung
    • Journal of KIISE:Information Networking
    • /
    • v.32 no.5
    • /
    • pp.633-640
    • /
    • 2005
  • This paper proposes and analyzes a message scheduling scheme and corresponding bandwidth allocation method for the hard real-time communication on dual standard 802.11 Wireless LANs. By making the superframeof one network precede that of the other by half, the dual network architecture can minimize the effect of deferred beacon and reduce the worst case waiting timeby half. The effect of deferred beacon is formalized and directly considered to decide the polling schedule of PCF phase. Simulation results executed via ns-2 show that the proposed scheme can improve the schedulability by 3$36\%$ for real-time messages and give $9\%$ more bandwidth to non-real-time messages for the given stream sets, compared with the network whose bandwidth is just doubled with the same MAC.