In the context of a government-owned public firm that competes with a private firm, this paper demonstrates how the government can maximize its true objective by assigning the public firm a different objective functio...
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In the context of a government-owned public firm that competes with a private firm, this paper demonstrates how the government can maximize its true objective by assigning the public firm a different objective function. Interestingly, this assigned objective function need bear no resemblance to the actual objective being sought, enabling the government to disguise a politically unpopular agenda and/or outside influence. (C) 2002 Elsevier Science B.V. All rights reserved.
In order to improve the setting accuracy of rolling force model, a comprehensive parameters adaptive objective function of rolling force was established. During the adaptive process, the adaptive coefficients of frict...
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ISBN:
(纸本)9783038351016
In order to improve the setting accuracy of rolling force model, a comprehensive parameters adaptive objective function of rolling force was established. During the adaptive process, the adaptive coefficients of friction coefficient and deformation resistance were taken as the optimized parameters, and the Rosenbrock algorithm was used to search the optimal solution of the objective function. The proposed adaptive method has been applied successfully to a 1450mm 5-stand tandem cold mill. Application results show that the forecast accuracy of rolling force model has been improved significantly.
This paper concerns the optimization of EEG signal parameters for epileptic seizure detection. In a previous study, a macroscopic model has been used to model various waveforms of EEG signal and to optimize its parame...
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ISBN:
(纸本)9781467366731
This paper concerns the optimization of EEG signal parameters for epileptic seizure detection. In a previous study, a macroscopic model has been used to model various waveforms of EEG signal and to optimize its parameters by means of a genetic algorithm (GA). In the GA-based method for EEG parameters estimation, an optimization procedure is used. The aim of the optimization procedure is to minimize an objective function. The minimized error function compares the desired waveform (real EEG signal) and the waveform of the signal provided by the model both in the time domain and frequency domain. In the present study, we propose a time-scale based representation for the objective function as an alternative to the time and frequency based objective function used in the early study. The proposed objective function takes into account the non-stationary nature of the EEG signal. The performance of the proposed wavelet-based objective function is compared to that of the spectral objective function.
Smart Grid Communication Network (SGCN) is the core architecture of the smart grid. In large-scale network deployment and heavy load scenarios, many existing routing protocols still present low reliability and instabi...
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ISBN:
(纸本)9781665495752
Smart Grid Communication Network (SGCN) is the core architecture of the smart grid. In large-scale network deployment and heavy load scenarios, many existing routing protocols still present low reliability and instability issues, which need to be optimized and improved. This paper studies a highly reliable routing protocol in the application scenario of the smart grid Aiming at the network load balancing problem under heavy load, we propose a high-reliability objective function (OF-HR). Furthermore, we modify the sending timer of the DODAG Information Object (DIO) to achieve the reliability of the routing protocol at the expense of certain node energy consumption. The simulation results based on the Contiki system and Cooja tool show that the OF-HR proposed in this paper improves the packet delivery by up to 32.2% in the same network topology compared with the objective function in the mainstream algorithms. In the circumstance of 60-80 Packets / (Point * Minute), DIO sending interval is reduced to about 1 minute indicating that our algorithm has high stability and robustness under the heavy load of the smart grid.
The amount of data represented by the Internet of Things (IoT) is continually growing and is expected to reach more than one third of the total amount of Internet traffic by 2020. Wireless sensors pose a great challen...
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ISBN:
(纸本)9781538647271
The amount of data represented by the Internet of Things (IoT) is continually growing and is expected to reach more than one third of the total amount of Internet traffic by 2020. Wireless sensors pose a great challenge because of the varying radio conditions and the limited energy and computational capabilities they have. This is why we have developed an objective function (OF) that uses fuzzy logic to dynamically adapt to variable environments in wireless networks. Simulation results will show that the proposed algorithm increases performance compared to other solutions by up to 15% in terms of throughput and by up to 14% in terms of Packet Delivery Ratio (PDR) without compromising energy consumption.
Within the context of the Internet of Things (IoT), the distance-vector IPv6 Routing Protocol for Low-power and Lossy Networks (RPL) is one of the most popular choices for the network routing layer. Within RPL, distan...
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ISBN:
(纸本)9781538672723
Within the context of the Internet of Things (IoT), the distance-vector IPv6 Routing Protocol for Low-power and Lossy Networks (RPL) is one of the most popular choices for the network routing layer. Within RPL, distance calculation is abstracted by the objective function (OF) and two OF implementations have been standardized, namely OF0 and MRHOF. However, these OFs build network topologies where bottleneck nodes may suffer from excessive unbalanced traffic load. The load distribution problem is a major issue for existing OFs defined in RPL because it decreases network performance and the network's lifetime. In this paper, we propose a new OF called the Traffic Aware objective function (TAOF), which balances the traffic load that each node processes in order to ensure node lifetime maximization. To implement this OF, we altered the DIO message format, introduced a new RPL metric, named Traffic Rate, and used a new parent selection algorithm. Simulation experiments have been conducted to examine the performance of our proposal. The results show that TAOF achieves enhanced performance in terms of Packet Delivery Ratio (PDR) and that it builds more stable networks with fewer parent changes.
Low power and lossy networks (LLNs) are constrained networks that need specific routing protocols able to meet application requirements such as latency and reliability. RPL was designed by the IETF ROLL working group ...
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ISBN:
(纸本)9781538677476
Low power and lossy networks (LLNs) are constrained networks that need specific routing protocols able to meet application requirements such as latency and reliability. RPL was designed by the IETF ROLL working group for such challenging networks. It defines an objective function (OF) that can operate according to a set of metrics and constraints to make nodes select best parents and then construct paths. Considering the vast areas of applications for RPL, used metrics and constraints combinations was left an open issue for implementation. In this paper, we propose an opportunistic fuzzy logic based OF (OPP-FL) that takes into consideration a novel routing metric measuring neighbor load in addition to traditional IETF ROLL specified metrics. Our proposed scheme combine through a fuzzy logic process the traditional expected transmission count (ETX) and Hop Count (HC) metrics to proposed Children Number (CN) metric. Simulation results reveal that compared to the based ETX OF, namely MRHOF and the OF-EC a fuzzy logic based OF has achieved better performances in terms of PDR and acceptable results in terms of delay when the network size expands without inducing high traffic overhead.
An unconstrained optimization model applicable to radial deviation measurement is established for assessing axis straightness errors by the minimum zone method. The properties of the objective function in the optimiza...
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ISBN:
(纸本)9783642232251
An unconstrained optimization model applicable to radial deviation measurement is established for assessing axis straightness errors by the minimum zone method. The properties of the objective function in the optimization model are thoroughly researched. On the basis of the modern theory of convex functions, it is strictly proved that the objective function is a continuous and non-differentiable and convex function defined on the four-dimensional Euclidean space R4. The minimal value of the objective function is unique and any of its minimal point must be its global minimal point. Any existing optimization algorithm, so long as it is convergent, can be used to solve the objective function to get the wanted values of axis straightness errors by the minimum zone assessment. An example is given to verify the theoretical results presented.
Over the most recent couple of years, the Internet of Things (IoT) has end up being an intriguing and promising worldview that means to add to endless applications by interfacing more physical "things" to th...
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ISBN:
(纸本)9781665440868
Over the most recent couple of years, the Internet of Things (IoT) has end up being an intriguing and promising worldview that means to add to endless applications by interfacing more physical "things" to the Internet. The Internet Engineering Task Force (IETF) created RPL as the routing protocol for low power and lossy networks (LLNs). RPL (Routing Protocol for Low-Power and Lossy Networks) is a routing protocol for remote sensors with low power consumptions and is flexible to handle. To be useful in various applications of LLN, RPL isolates packet handling and sends information from the same routing objective. In this paper, we mainly focus on analysis and studying existing RPL routing protocol and performance is carried out using Contiki OS. Furthermore, the existing RPL objective function (MRHOF and OF0) are analysis under different metrics such as Packet Delivery, average delay and energy consumption conducted over Cooja with Z1 mote. Finally the result helps in better understanding of the existing objective functions and their performance towards the RPL protocol. This analysis will be useful in providing guidelines for improving the RPL protocol in future works.
This paper presents a novel objective function to obtain the optimum relay settings of directional over-current relays (DOCRs). The proposed improved objective function (IOF) is developed to solve the problems of prev...
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ISBN:
(数字)9789811502064
ISBN:
(纸本)9789811502064;9789811502057
This paper presents a novel objective function to obtain the optimum relay settings of directional over-current relays (DOCRs). The proposed improved objective function (IOF) is developed to solve the problems of previously proposed OFs. The proposed research work modifies the previous OFs by introducing a new weighting factor and adding a new term, for fixing mis-coordination problem and minimizing the operating times of both primary and backup relays. The performance of the proposed IOF is evaluated by using 3- and 8-bus test systems. The simulation results reflect the superiority of IOF, compared to other variety of OFs presented in the literature.
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