Over the past years, different approaches have been proposed for circuital modeling photovoltaic modules. Most of these approaches introduce simplifications and/or approximations techniques or exploit inaccurate data ...
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ISBN:
(纸本)9781467381031
Over the past years, different approaches have been proposed for circuital modeling photovoltaic modules. Most of these approaches introduce simplifications and/or approximations techniques or exploit inaccurate data interpolated from the plots representing panel characteristic curves: this in order to overcome the treatment of transcendental equations or to add points for numerical fitting. Unfortunately, this leads to ineffective algorithms and inaccurate results. In this work, we propose a fast and powerful mobile application, named PV Panel Modeling, for the identification of PV panels from datasheet. PV Panel Modeling is based on a complete theoretical and practical analysis on the extraction of one-diode model parameters. In particular, the proposed procedure separates the independent parameters from the dependent ones by using suitable algebraic manipulations of the commonly used equations. Hence, it is possible to verify the open circuit, short circuit and maximum power point conditions, and to reduce the dimensions of the search space of the parameters. The application and its core are designed in order to be cross platform and ensure high performances. Here, we propose an implementation for handheld devices based on Android operating system. Finally, the obtained results have been validated on hundreds of PV panels belonging to the California Energy Commission database.
MIMO systems transmit signals by multiple antennas at the terminals, thus, to get spatial diversity gain and improve system capacity dramatically. Compared with single MIMO systems, the distributed MIMO system has hig...
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ISBN:
(纸本)9781467390880
MIMO systems transmit signals by multiple antennas at the terminals, thus, to get spatial diversity gain and improve system capacity dramatically. Compared with single MIMO systems, the distributed MIMO system has higher coverage and larger capacity. MIMO systems using the joint coding technique through the full diversity of the space-time code can not only obtain the full diversity gain, but also improve spectrum efficiency effectively. But the detection complexity is high at the receiving terminal and information interference exists when transferring between antennas. Space-time coding can reduce the information interference between antennas and obtain diversity gain without sacrificing the bandwidth. The cyclic delay methods can effectively reduce the detection complexity. We present a high rate of distributed cooperative MIMO transmission scheme combining with space-time coding technique and cyclic delay technology. The transmitting terminal sends message to the relay nodes. Meanwhile, the source through the direct channel broadcasts information to all terminals. After the space-time coding, the received information at relay nodes is sent to the transmitters using cyclic delay method and amplifying forwarding (AF) method. This program applies to scene of both the communication source node and relay nodes all configured with multiple antennas. And the simulation results show that this two-way scheme we proposed can significantly improve the diversity gain and the total transmission rate, and enlarge the coverage of wireless network.
In this paper, the non-negative decentralized completion problem of the in-complete internet latency matrix is studied. On the basis of the low-rank approximation of matrix, we componentize this problem into a couple ...
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ISBN:
(纸本)9781467390880
In this paper, the non-negative decentralized completion problem of the in-complete internet latency matrix is studied. On the basis of the low-rank approximation of matrix, we componentize this problem into a couple of convex optimization problems by estimating the 10 norm of this matrix, and then solve it by alternative direction algorithm. Owing to the asymmetry and the negative definite characteristic of the matrix caused by the difference between autonomous system routing strategies, some negative entries inevitably exist in the completed matrix. Unlike traditional non-negative completion algorithms, this paper does not try to prevent the generation of negative entries. As an alternative, this paper presents a novel and much simpler non-negative ensuring scheme named NADeMaC, which calibrates the negative entries by a prior positive estimation value after they appeare. Theoretical analysis shows that the accuracy of our algorithm is at least no less than traditional methods. Furthermore, our experiments show that our method is far better than traditional non-negative ensuring scheme.
The cloud computing paradigm enables the development of applications that can elastically react to changes in their environment by autonomously provisioning and releasing infrastructure resources. However, current app...
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ISBN:
(纸本)9781467372848
The cloud computing paradigm enables the development of applications that can elastically react to changes in their environment by autonomously provisioning and releasing infrastructure resources. However, current applications need to be specifically tailored to a concrete cloud provider infrastructure, leading to vendor lock-in. Migrating applications to the cloud or between cloud providers is challenging due to differences in deployment directives, available services, and programming interfaces. Existing infrastructure as code approaches closely tie application artifacts to their deployment directives and do not allow for a clear separation of application artifacts from deployment infrastructure. In this paper, we present Smart Fabric, a methodology and accompanying toolset for infrastructure-agnostic deployment of application artifact topologies based on a constraint-based, declarative specification of the required deployment infrastructure. Our framework allows for seamless migration of application topologies between deployment targets and enables independent, parallel evolution of both, applications and underlying infrastructure. We discuss the feasibility of the proposed methodology and prototype implementation using representative applications from the internet of Things and smart city domains.
On the base of introducing key techniques such as mobile cloud computing, the trusted third party, REST services, etc, this paper elaborated the construction steps of agent model, introduced the access mode of mobile ...
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ISBN:
(纸本)9781785610899
On the base of introducing key techniques such as mobile cloud computing, the trusted third party, REST services, etc, this paper elaborated the construction steps of agent model, introduced the access mode of mobile cloud computing based on proxy, designed a security management model based on trusted agent who acts as a trusted third party to provide multiple levels, and distributed end-to-end security services.
Two of the prominent dimensions behind the development of cross-platform UIs are the UI distribution and UI migration. In UI distribution, since UI elements of a given application has to be distributed across more tha...
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If (electronic) computations need to be undertaken, then mostly performance or commercial aspects lead to the selection for an optimal executing computer. In case the beneficiary of the computation upshots does not wh...
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ISBN:
(纸本)9783319149769;9783319149776
If (electronic) computations need to be undertaken, then mostly performance or commercial aspects lead to the selection for an optimal executing computer. In case the beneficiary of the computation upshots does not wholly confide in any computers except his ones, trust becomes his major decision criterion instead. Blind computing can do the trick to (re) win the beneficiary's confidence. This paper ameliorates the well-known cryptosystem SecureString 2.0 concerning privacy through pangram ciphertexts and referring integrity through secret sharing. The emerging cryptosystem of this amelioration is called SecureString 3.0 that facilities blind computing on encrypted character strings through an untrusted host.
Usage of wireless networks among the users is apparently high. But, efficiency of the network gets decreased because of the challenges in the network. In proxy mobile IPv6 (PMIPv6), the message exchange for location u...
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Usage of wireless networks among the users is apparently high. But, efficiency of the network gets decreased because of the challenges in the network. In proxy mobile IPv6 (PMIPv6), the message exchange for location update by any mobile device is established in centralized environment. Here, the messages are sent and received through local mobility anchor with centralized feature. As a result, there is devastating traffic at local mobility anchor which increases the cost of network. Also, the location update in distributed mobility environment is vulnerable to attacks such as false binding update, man-in-the-middle, replay attack etc. Therefore, the development of location update scheme necessitates the security enhancement and reduction in cost. Hence, the present paper proposes a new secure and efficient location update scheme using tokenization. It eliminates the additional message exchanges such as proxy binding update, binding query and acknowledgements between the hosts required in the earlier works. Here, the traffic overhead is controlled by distributing the token of mobile node with mobile access gateway in distributed mobility environment. The security of the proposed scheme is validated using AVISPA - a security model checker. Finally, the analysis of security and performance evaluation demonstrates that the proposed scheme shows better security and significant reduction in the cost of signaling messages and data packet delivery. (C) 2015 The Authrs. Published by Elsevier B.V.
As a product of the development of the internet, security issues of cloud computing has attracted much attention whether it is from the cloud providers39; point of view or from the perspective of cloud users. From t...
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ISBN:
(纸本)9781785610899
As a product of the development of the internet, security issues of cloud computing has attracted much attention whether it is from the cloud providers' point of view or from the perspective of cloud users. From the view of information security, risk assessment model is established in this paper using game theory, which involves the damage and the restore of the cloud system. Using the framework, the interaction between attacker and defender has been analysed and risk assessment of vulnerable points in cloud environment is conducted.
This invited paper makes an overview of our works addressing discrete control-based design of adaptive and reconfigurable computing systems, also called autonomic computing. They are characterized by their ability to ...
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ISBN:
(纸本)9783319149769;9783319149776
This invited paper makes an overview of our works addressing discrete control-based design of adaptive and reconfigurable computing systems, also called autonomic computing. They are characterized by their ability to switch between different execution modes w.r.t. application and functionality, mapping and deployment, or execution architecture. The control of such reconfigurations or adaptations is a new application domain for control theory, called feedback computing. We approach the problem with a programming language supported approach, based on synchronous languages and discrete control synthesis. We concretely use this approach in FPGA-based reconfigurable architectures, and in the coordination of administration loops.
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