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The Influence of Positions and Formats of Mobile Applications on the Advertising Effectiveness of SmartphonesHu, Ting-ting 27 August 2012 (has links)
Compared with the advertisement on traditional media, mobile applications are totally different in usage situation, operating interfaces and communication modes with consumers. The study analyzes the influence of the positions (such as, pre-game advertisement and peripheral game advertisement) and formats (such as, dynamic banners advertisement and rich media advertisement) of advertisement on advertising effects. In addition, flow level is the modifying variable. The study collected a total of 220 effective samples by using judgmental sampling procedures to send out questionnaires over the Internet. Respondents must have experiences in playing Angry Bird on a smart phone
The research results include: (1) The positions of advertisement influence significantly over the advertisement attitudes, brand and product memories; (2) The formats of advertisement influence significantly over the advertisement attitudes, and (3) The positions and formats of advertisement influence significantly over the advertisement attitudes when respondents are in low flow level. On the contrary, the positions and formats of advertisement influence significantly over brand and product memories when respondents are in high flow level.
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A Fault Tolerant Routing/Communication Methodology for Reliability Enhancement in Smart GridsCheng, Bo-Chuan 30 August 2012 (has links)
This paper presents a fault-tolerant (fault tolerant) can enhance the communications capabilities, improve the reliability and efficiency of in smart grid signal transmission. Meter layout with PLC or ZigBee in any topology, meter adopt Minimum Spanning Tree algorithm to achieve shortest distance and lost cost in PLC; when device contain wireless receiver, meter adopt Hungarian algorithm can search nearest itself¡¦s device to receive device information. The paper propose two fault tolerant methods: static and dynamic methods. Static method is a meter transmit to another one with regular communication even if a meter tranfmit with ZigBee; dynamic method is a meter transmit another one, ZigBee has low priority according to cost function in effective communication range.
The paper simulation in any 100m2 topology, randon produce 13 SmartUnit with different number of meters and coordinate, two fault tolerant method can achieve 100% fault coverage in single link fault case; but static method use FTGDB(Fault Tolerant Generalized De Bruijn algorithm) multiple fault coverage can achieve 43% with d=4 case; dynamic method use Kth shortest path algorithm multiple fault coverage can achieve 61% with d=4 case. In other words FTGDB has average 100 communication line allow average 43 communication line fault tolerant ability with d=4 case in 13 SmartHomeUnit; Kth shortest path algorithm has average 100 communication line allow average 61 communication line fault tolerant ability with d=4 case in 13 SmartHomeUnit.
If after fault tolerant achievement, count to demand energy and delay time with PLC and ZigBee, then it can offer electric company information. Electric company evaluate electric cost¡Breal time price etc¡K
The paper propose a online demand response method, the method is Online Priority Tree algorithm to be counted end device¡¦s rank priority according to device importance.
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Controlling Performance of Laminated Composites Using Piezoelectric MaterialsHasan, Zeaid 2010 December 1900 (has links)
Composite materials are increasingly used in aerospace, underwater, and automotive structures. Their use in structural applications is dictated by the outstanding strength and stiffness while being lightweight in addition to their flexibility in tailoring the desired performance in the design of structures. The present study focuses on the failure analysis and shape control of smart composite laminates under coupled hygrothermal, electric and mechanical stimuli. A linear thermo-electro-elastic constitutive model for transversely isotropic materials is used for each ply in the composite laminates. The first-ply failure and ultimate laminate failure criteria of composite laminates are used to predict the failure stress and mode of the composite laminate where we incorporate various commonly known macroscopic failure criteria including Tsai-Hill, Tsai Wu, maximum stress and maximum strain for each lamina.
We study the use of piezoelectric materials such as lead zirconate titanate (PZT) and piezoelectric fiber composites as actuators for controlling deformation in composite laminates; this study focuses on bending deformation. The purpose is to minimize unwanted deformation, such as the one due to hygrothermal effect, by applying counter deformation to avoid failure in such composite laminates. In addition, analysis based on the Classical Laminate Theory (CLT) is performed for Carbon/Epoxy (AS4/3501-6) thin laminate with stacking sequence [90/45/-45/0]s under uniaxial and biaxial in-plane loading.
One of the major types of failure in smart structures is caused by debonding of the actuator from the host structure which is caused by the high stress discontinuity between the interface of the host structure and the active part. By using embedded actuators, such that the active part is incorporated into one of the layers of the composite beam during the manufacturing process, the stress concentration effect can be reduced while obtaining similar actuation values. Moreover, a control algorithm is proposed that enables the composite laminate to overcome the failure load by using piezoelectric materials where a counter electric voltage could be applied which prevents failure from occurring. Furthermore, computer software called “Hyper Composite” was developed using Action Script® and Adobe Flash® in order to perform stress and failure analysis for general composite laminates. Several carpet plots were also generated to show the interacting behavior of two independent variables such as Young’s modulus, Poisson’s ratio, shear modulus and the coefficient of thermal and moisture expansion at different percentile constitutions for the laminate different plies. This computer software is useful for estimating overall properties of smart composite laminates in designing smart composite structures.
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Design, Simulation, and Analysis of Substation Automation NetworksKembanur Natarajan, Elangovan 2011 May 1900 (has links)
Society depends on computer networks for communication. The networks were built to support and facilitate several important applications such as email, web browsing and instant messaging. Recently, there is a significant interest in leveraging modern local and wide area communication networks for improving reliability and
performance in critical infrastructures. Emerging critical infrastructure applications, such as smart grid, require a certain degree of reliability and Quality of Service (QoS). Supporting these applications requires network protocols that enable delay sensitive packet delivery and packet prioritization. However, most of the traditional networks are designed to provide best effort service without any support for QoS. The protocols used in these networks do not support packet prioritization, delay requirements and reliability.
In this thesis, we focus on the design and analysis of communication protocols for supporting smart grid applications. In particular, we focus on the Substation
Automation Systems (SAS). Substations are nodes in the smart grid infrastructure that help the in transportation of power by connecting the transmission and distribution lines. The SAS applications are con figured to operate with minimal human intervention. The SAS monitors the line loads continuously. If the load values are too high and can lead to damage, the SAS declares those conditions as faults. On fault detection, the SAS must take care of the communication with the relay to open the circuit to prevent any damage. These messages are of high priority and require reliable, delay sensitive delivery. There is a threshold for the delay of these messages, and a slight increase in the delay above the threshold might cause severe damages. Along with such high priority messages, the SAS has a lot of background traffic as well. In spite of the background traffic, the substation network must take care of delivering the priority messages on time. Hence, the network plays a vital role in the operation of the substation.
Networks designed for such applications should be analyzed carefully to make sure that the requirements are met properly. We analyzed and compared the performance of the SAS under di erent network topologies. By observing the characteristics of the existing architectures, we came up with new architectures that perform better. We have suggested several modi cations to existing solutions that allow significant improvement in the performance of the existing solutions.
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A New Designed MAC Layer Protocol for Space Division Multiple Access in Wireless Ad Hoc NetworksTseng, Kuo-Shu 03 September 2003 (has links)
Typically, MAC protocols for mobile ad hoc networks assume omnidirectional antennas, and use of directional antennas offers many advantages, such as range extension, reduced co-channel interference, increased the degree of spatial reuse, improved the throughput of networks, and reduced the transmission power. There are many wireless ad hoc MAC protocol have been proposed. However, these protocols do not provide significant improvement of network performance because they can¡¦t let nodes to support multiple simultaneous transmissions or receptions ability.
In this paper, we proposed a newly designed MAC protocols, we used adaptive beam-forming system to reduce the co-channel interference problem, and our proposed MAC protocol will enable nodes with multiple simultaneous transmissions and receptions ability. The handshake mechanism of proposed MAC protocol is that used receiver initialize handshake mechanism such as MACA/BI. We changed the Ready-to-Receive (RTR) control packet, which was used to poll neighbor nodes to be a dual-used control packet, Ready-to-Receive-Transmission (RTRT). Our simulation results will show that our proposed MAC protocol do exploit the advantage of space division multiple access that significantly reduced the problem of poor networks throughput which caused by bottleneck nodes in wireless ad hoc networks.
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Robust Remote Authentication Schemes with Smart CardsChan, Yung-Cheng 14 July 2005 (has links)
Due to low computation cost and convenient portability, smart cards are usually adopted to store the personal secret information of users for remote authentication. Although many remote authentication schemes using smart cards have been introduced in the literatures, they still suffer from some possible attacks or cannot guarantee the quality of performance for smart cards. In this thesis, we classify the security criteria of remote authentication and propose a new remote login scheme using smart cards to satisfy all of these criteria. Not only does the proposed scheme achieve the low computation requirement for smart cards, but it can withstand the replay and the off-line dictionary attacks as well. Moreover, our scheme requires neither any password table for verification nor clock synchronization between each user and the server while providing both mutual authentication and the uniqueness of valid cards.
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Customer Efficient Electronic Cash ProtocolsLin, Bo-Wei 27 July 2005 (has links)
The technology of electronic cash makes it possible to transmit digital money over communication networks during electronic transactions. Owing to the untraceability and unforgeability properties, electronic cash can protect the privacy of customers and guarantee the security of payments in the transactions. This manuscript introduces an efficient electronic cash protocol where it only requires minimal storage for each customer to withdraw w dollars from the bank and spend the w dollars in a sequence of transactions. Compared with traditional electronic cash protocols, the proposed method greatly reduces not only the storage required for the customers but the communication traffic in the transactions as well. Furthermore, the computation cost of the entire protocol is lower than the traditional ones and it also achieves the customer efficiency property. It turns out that the proposed protocol is much more suitable for the storage-limited or hardware-limited environments, such as smart card computing or mobile commerce, than the traditional electronic cash protocols in a sequence of payments. In addition, we examine the security of the proposed electronic cash protocol from the customer¡¦s, the shop¡¦s, and the bank¡¦s points of view, respectively. Since the proposed protocol is based on a generic partially blind signature scheme, it can be implemented by any partially blind signature scheme as long as it is secure and user efficient.
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Tracking-Beam Arrays Implementation of Smart Antennas in DS-CDMA Communication SystemsTsai, Shun-Hwa 21 June 2001 (has links)
Abstract
Because of the rapid development of mobile communications, the bandwidth efficiency and the communication quality have become interesting issues for researchers. Multipath fading and multiple-access interference (MAI) are the main barriers of performance improvement. Fortunately, spread spectrum techniques have an inherent ability of anti-interference and anti-multipath. Thus, the commercialized CDMA systems are developed on the basis of spread spectrum techniques.
Recently, smart antennas using adaptive array techniques have been applied in CDMA communications. There are two different approaches to realize smart antenna systems: one is named as ¡¥switching-beam arrays¡¦; the other is called ¡¥tracking-beam arrays¡¦. Switching-beam arrays use a number of fixed beams at an antenna site. The mobiles select the beam that offers the best signal enhancement and interference reduction. On the other hand, tracking-beam arrays can adjust their pattern to track desired signals, reduce interference, and collect correlated multipath power.
In this thesis, several smart antenna systems based on tracking-beam arrays in DS-CDMA systems are developed. The proposed smart antennas comprise two main structures, i.e., the direction-of-arrival (DOA) tracking and the dynamic beamforming. The improved recursively updated method and the Kalman filter algorithm are employed to track the mobiles¡¦ DOAs. By referring to the estimated DOA, the minimum- variance-distortionless-response (MVDR) dynamic beamformer produces a main beam to target on a certain mobile and simultaneously, interferences from other mobiles are suppressed. Therefore, the MAI in DS-CDMA systems can be suppressed properly at all times. Besides, the inherent processing gain in DS-CDMA systems is utilized to break through the limit that the number of mobiles must be smaller than that of sensors. The proposed smart antennas work properly even the number of mobiles exceeds that of sensor. Simulation results show that the advantages of the proposed technique over the conventional tracking-beam arrays.
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Study on MultiUser Detection with Smart AntennaWang, Wu-Chi 21 August 2003 (has links)
Smart antenna, which weights are obtained by Wiener solution, would suppress some undesired interference signals in spatial domain. The other interference signals that cannot be suppressed by smart antenna or caused by near-far effect will be post-processed by multiuser detectors. In the proposed algorithm, the cross-correlation matrix of desired signal and received signal from smart antenna algorithm would be applied to multiuser detector to reduce the complexity. From computer simulation results, the proposed algorithm has lower complexity and better BER performance than separate smart antenna or multiuser detection algorithms. Detail derivations of complexity and BER performance are also provided in this thesis.
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The development and implementation of an ionic-polymer-metal-composite propelled vessel guided by a goal-seeking algorithmVickers, Jason Aaron 17 September 2007 (has links)
This thesis describes the use of an ultrasonic goal-seeking algorithm while using ionic polymer metal composite (IPMC), an electroactive polymer, as the actuator to drive a vessel towards a goal. The signal transmitting and receiving circuits as well as the goal seeking algorithm are described in detail. Two test vessels were created; one was a larger vessel that contained all necessary components for autonomy. The second was a smaller vessel that contained only the sensors and IPMC strips, and all power and signals were transmitted via an umbilical cord. To increase the propulsive efforts of the second, smaller vessel, fins were added to the IPMC strips, increasing the surface area over 700%, determined to yield a 22-fold force increase. After extensive testing, it was found that the three IPMC strips, used as oscillating fins, could not generate enough propulsion to move either vessel, with or without fins. With the addition of fins, the oscillating frequency was reduced from 0.86-Hz to 0.25-Hz. However, the goal-seeking algorithm was successful in guiding the vessel towards the target, an ultrasonic transmitter. When moved manually according to the instructions given by the algorithm, the vessel successfully reached the goal. Using assumptions based on prior experiments regarding the speed of an IPMC propelled vessel, the trial in which the goal was to the left of the axis required 18.2% more time to arrive at the goal than the trial in which the goal was to the right. This significant difference is due to the goal-seeking algorithmâÂÂs means to acquire the strongest signal. After the research had concluded and the propulsors failed to yield desired results, many factors were considered to rationalize the observations. The operating frequency was reduced, and it was found that, by the impulse-momentum theorem, that the propulsive force was reduced proportionally. The literature surveyed addressed undulatory motion, which produces constant propulsive force, not oscillatory, which yields intermittent propulsive force. These reasons among others were produced to rationalize the results and prove the cause of negative results was inherent to the actuators themselves. All rational options have been considered to yield positive results.
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