• Title/Summary/Keyword: Dynamic ID

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An inverse dynamic torque control of a six-jointed robot arm using neural networks (신경회로를 이용한 6축 로보트의 역동력학적 토크 제어)

  • 조문증;오세영
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10a
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    • pp.1-6
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    • 1990
  • Neural network is a computational model of ft biological nervous system developed ID exploit its intelligence and parallelism. Applying neural networks so robots creates many advantages over conventional control methods such as learning, real-time control, and continuous performance improvement through training and adaptation. In this paper, dynamic control of a six-link robot will be presented using neural networks. The neural network model used in this paper is the backpropagation network. Simulated control of the PUMA 560 am shows that it can move a high speed as well as adapt to unforseen load changes and sensor noise. The results are compared with the conventional PD control scheme.

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An Improvement of Bin-slotted Anti-collision Algorithm for Ubiquitous ID System

  • Kim Ji-Yoon;Kang Bong-Soo;Yang Doo-Yeong
    • International Journal of Contents
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    • v.2 no.1
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    • pp.34-38
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    • 2006
  • In this paper, an overview of anti-collision algorithm for RFID system of a standard EPC Class1 protocol is presented, and the binslotted dynamic search algorithm (BDS) based upon the slotted ALOHA and binary tree procedure is proposed and analyzed. Also, the performance is evaluated as comparing the BDS algorithm with the standard bin-slotted algorithm (BSA) through the simulation program. The performance of the proposed BDS algorithm is improved by dynamically identifying the collided-bit position and the collided bins stored in the stack of the reader. As the results, the number of request command that a reader send to tags in the reader s interrogation zone and the total recognition time are decreased to 59% as compared with BSA algorithm. Therefore, the tag identification performance is fairly improved by resolving a collision problem using the proposed BDS algorithm.

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A Study on Fracture Parameters for PVC/MBS Composites under Low Velocity Impact (저속 충격시 PVC/MBS재료의 파괴특성에 관한 연구)

  • 최영식;박명균;박세만
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.837-840
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    • 2002
  • An analysis method for rubber toughened PVC is suggested to evaluate critical dynamic strain energy release rates($G_c$) from the Charpy impact energy measurements. An instrumented Charpy impact tester was used to extract ancillary information concerning fracture parameters in addition to total fracture energies and maximum critical loads. The dynamic stress intensity factor $K_{Id}$ was computed for varying amounts of rubber contents from the obtained maximum critical loads and also toughening effects were investigated as well. The fracture surfaces produced under low velocity impact fur PVC/MBS composites were investigated by SEM. The results show that MBS rubber is very effective reinforcement material for toughening PVC.C.

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A Channel Allocation Protocol for Collision Avoidance between Reader in 2.4GHz Multiple Channel Active RFID System (2.4GHz 다중채널 능동형RFID시스템에서 리더간 충돌회피를 위한 채널 할당 프로토콜)

  • Kim, Dong-Hyun;Lee, Chae-Suk;Kim, Jong-deok
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.139-142
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    • 2009
  • RFID(Radio Frequency IDentification) technology is an automatic identification method using radio frequencies between RFID reader which collects the information and tag which transmits the information. RFID technology develops passive RFID which transmit the only ID to active RFID which transmit the additional information such as sensing information. However, ISO/IEC 18000-7 as active RFID standard has a problem which cannot use multiple channel. To solve this problem, we use the 2.4GHz bandwidth technology and we propose the dynamic channel allocation method which can efficiently allot a channel. we show the operation of the dynamic channel allocation method through design and implement with CC2500DK of Taxas Instrument.

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Dynamic Lung Compliance in Normal Subjects Measured by Pneumatograph (Pneumotachograph 로 측정한 건강인의 동적 폐 Compliance)

  • 이성행
    • Journal of Chest Surgery
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    • v.10 no.2
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    • pp.195-204
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    • 1977
  • Dynamic lung compliance was measured in healthy ten young[mean age, 26 years] male and five young[mean age, 25 years] female. Lung volume was integrated of the rate of flow signal which was obtained by using pneumotachograph and differential pressure transducer[PM 5, Statham]. Intrapleural pressure was measured as that of intraesophagel pressure. Esophageal ballon, 15. 5cm in length, 4ml of luminal capacity and made of thin latex, was connected to the polyethylene tube that had 12-14 side holes and was of 1.5mm of ID. Transpulmonary pressure was traced by means of differential pressure transducer[PM 131, Statham] to which connected the esophageal balloon catheter and connection tube from mouth piece. Lung volume and transpulmonary pressure were photographed by cathode ray oscilloscope camera while the subjects were breathing spontaneously. Dynamic lung compliance loop was displayed on single trace monitor and subtraction was performed for the quasi-static hysteresis. Dynamic lung compliance was measured, 1. by plotting the pressure-volume relationship 2. from the subtracted pressure-volume loop. Results were as follows. 1. Dynamic lung compliances measured by plotting of healthy young male and female were $0.202{\pm}0.06$ and $0.190{\pm}0.023L/cm$ $H_2O$ respectively. 2. When measured from subtraction loop, dynamic lung compliance for male and female were $0.327{\pm}0.107$, and $0.27{\pm}0.06L/cm$ $H_2O$ respectively. 3. Dynamic chest wall and total respiratory system compliance were also measured. 4. Dynamic lung compliance by plotting appeared to be essentially same when compared to that of static compliance reported previously from our laboratory, however, that obtained from subtraction loop revealed higher values than the compliances obtained by plotting and that of static compliance.

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Lessons learned from Operation Iraqi Freedom(OIF) for ROK forces (이라크전쟁의 군사적 교훈)

  • Mun, Gwang-Geon
    • Journal of National Security and Military Science
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    • s.1
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    • pp.71-111
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    • 2003
  • The key lessons of the very complex modern war can be dangerously misleading to the outsiders. The efforts trying to draw lessons learned from the Iraq War (OIF : Operation Iraqi Freedom) may be biased by the view of point by Americans, because most of war episodes have been come from the Western media coverage. More serious bias can be committed thanks to the differences of warfighting doctrines and military technology between US forces and ROK forces. However, OIF-fought allied commanders and outside military experts said this campaign exemplified 21st-century warfare: swift, agile and decisive, employing overpowering technology to bring relentless violence to bear in many places at once. Even though the campaign evolved differently than anticipated, allied forces regrouped and regained the initiative remarkably quickly, thanks in large part to a new command flexibility, tied to new technology that made possible the more rapid sharing of data. These factors permitted "new air-land dynamic". The things that compel that are good sensors networked with good intelligence disseminated through a robust networking system, which then yields speed. Speed turns out to be a very important factor for conducting "Rapid Decisive Operations" relied on joint "Mass of Effects". ROK forces facing the heaviest ground threat in the world may learn more from Cold War era-typed US Army 3rd Infantry Division (3ID), which operating considerably beyond existing doctrine. 3ID flew its personnel into Kuwait to meet up with equipment already located in the region as pre-positioned stock. During OIF, the division conducted continuous offensive operations over 230km deep battlespace for 21 days. The lessons learned for ROK army to prepare tomorrow's war may be found from 3ID in its training, command and control, task organization, firepower and battlespace management, and logistics.

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Fuzzy Relevance-Based Clustering for Routing Performance Enhancement in Wireless Ad-Hoc Networks (무선 애드 혹 네트워크상에서 라우팅 성능 향상을 위한 퍼지 적합도 기반 클러스터링)

  • Lee, Chong-Deuk
    • Journal of Advanced Navigation Technology
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    • v.14 no.4
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    • pp.495-503
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    • 2010
  • The clustering is an important mechanism thai provides information for mobile nodes efficiently and improves the processing capacity for routing and the allocation of bandwidth. This paper proposes a clustering scheme based on the fuzzy relevance degree to solve problems such as node distribution found in the dynamic property due to mobility and flat structure and to enhance the routing performance. The proposed scheme uses the fuzzy relevance degree, ${\alpha}$, to select the cluster head for clustering in FSV (Fuzzy State Viewing) structure. The fuzzy relevance ${\alpha}$ plays the role in CH selection that processes the clustering in FSV. The proposed clustering scheme is used to solve problems found in existing 1-hop and 2-hop clustering schemes. NS-2 simulator is used to verify the performance of the proposed scheme by simulation. In the simulation the proposed scheme is compared with schemes such as Lowest-ID, MOBIC, and SCA. The simulation result showed that the proposed scheme has better performance than the other existing compared schemes.

Precise-Optimal Frame Length Based Collision Reduction Schemes for Frame Slotted Aloha RFID Systems

  • Dhakal, Sunil;Shin, Seokjoo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.1
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    • pp.165-182
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    • 2014
  • An RFID systems employ efficient Anti-Collision Algorithms (ACAs) to enhance the performance in various applications. The EPC-Global G2 RFID system utilizes Frame Slotted Aloha (FSA) as its ACA. One of the common approaches used to maximize the system performance (tag identification efficiency) of FSA-based RFID systems involves finding the optimal value of the frame length relative to the contending population size of the RFID tags. Several analytical models for finding the optimal frame length have been developed; however, they are not perfectly optimized because they lack precise characterization for the timing details of the underlying ACA. In this paper, we investigate this promising direction by precisely characterizing the timing details of the EPC-Global G2 protocol and use it to derive a precise-optimal frame length model. The main objective of the model is to determine the optimal frame length value for the estimated number of tags that maximizes the performance of an RFID system. However, because precise estimation of the contending tags is difficult, we utilize a parametric-heuristic approach to maximize the system performance and propose two simple schemes based on the obtained optimal frame length-namely, Improved Dynamic-Frame Slotted Aloha (ID-FSA) and Exponential Random Partitioning-Frame Slotted Aloha (ERP-FSA). The ID-FSA scheme is based on the tag set estimation and frame size update mechanisms, whereas the ERP-FSA scheme adjusts the contending tag population in such a way that the applied frame size becomes optimal. The results of simulations conducted indicate that the ID-FSA scheme performs better than several well-known schemes in various conditions, while the ERP-FSA scheme performs well when the frame size is small.

Security Analysis and Enhancement of Tsai et al.'s Smart-Card Based Authentication Scheme (스마트카드 기반 Tsai et al. 인증기법의 안전성 분석과 새로운 보안기법 연구)

  • Kim, Myungsun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39B no.1
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    • pp.29-37
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    • 2014
  • In this paper we show that a dynamic ID authentication scheme using smart cards proposed by Tsai et al. is not secure against DoS attack and insider attack. Further we claim that their scheme may raise a security problem when a user changes his/her password. Then we come up with a security-enhanced version only with small additional computational cost. Our scheme is based on the security of cryptographic hash function and the infeasibility assumption of discrete logarithm problem. In addition, we provide details of security and computational cost analysis.

The QoS Guarantees of Multimedia Traffic using MIP-DUDN with RSVP in Mobile Computing Environments (이동 컴퓨팅 환경에서 RSVP가 적용된 MIP-DUDN을 이용한 멀티미디어 트래픽의 QoS 보장)

  • Han, Seung-Jin;Lee, Jeong-Hyeon
    • The KIPS Transactions:PartC
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    • v.8C no.5
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    • pp.667-676
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    • 2001
  • We have solved a problem occurring in case that RSVP is applied to existing wired network in order to guarantee a QoS of multimedia traffic in mobile computing environment in this paper. If MN moves to another area when Mobile IP is applied to RSVP, HA makes new tunnel to FA because SESSION ID of MN is changed. However, we suggest MIP-DUDN method, which applied RSVP. Although MN moves to another area in this method, it does not make new tunnel because it eliminates the problem of existing Triangle Routing Problem. We design the new protocol of RMIP-DUDN and compare with the method of existing Mobile IP applied to RSVP.

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