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Design of an Efficient RPL objective function for Internet of Things Applications

INTERNATIONAL JOURNAL OF ADVANCED COMPUTER SCIENCE AND APPLICATIONS 2021年第6期12卷 228-235页

作者： Kuwelkar, Sonia Virani, H. G. Goa Coll Engn Elect & Telecommun Dept Ponda Goa India

Over the decade, a rapid growth in use of smart devices connected and communicating over the Internet is seen in various domains. The IPv6 Routing protocol for Low power and Lossy Networks (RPL) is the routing backbone of such IOT networks. RPL is a proactive, distance vector protocol which constructs the routes based on an objective function. The performance of RPL protocol largely depends on the design of objective function. Depending on application requirements, the RPL standard offers flexibility in design of the objective function and scope for improving the routing process. In this paper, an efficient objective function, RPL-FZ, is proposed. Speedy communication across nodes, low energy consumption and reliable data delivery is key to achieve quality of Service. Considering this, RPL-FZ uses relevant metrics like Residual Energy of Node, Delay and ETX (Expected Transmission count) to make the routing decisions. The metrics are combined using fuzzy logic technique to obtain a single metric Quality for each neighbor node. The neighbor with highest value of Quality is chosen as best parent to forward sensed data toward the collection unit. The proposed objective function RPL-FZ is integrated in the Contiki OS and network simulations are performed using the COOJA simulator. The performance evaluation reveals that RPL-FZ achieves 7% higher Packet Delivery rate, 8% lower energy consumption and 8% lesser latency as compared to single metric based standard objective functions OF0 and MRHOF.

关键词： Internet of things low power Lossy Networks IPv6 routing protocol for LLN objective function fuzzy logic

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Time Domain objective function Based on Euclidean Distance Matrix and its Application in Optimization of Short Pulse Power Divider

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IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS 2016年第1期26卷 4-6页

作者： Li, Shunli Liu, Leilei Yin, Xiaoxing Zhao, Hongxin Southeast Univ State Key Lab Millimeter Waves Nanjing 210096 Jiangsu Peoples R China Nanjing Univ Posts & Telecommun Nanjing 210003 Jiangsu Peoples R China

A time domain objective function based on the normalized Euclidean distance (NED) matrix of general short pulse network is proposed and is employed to optimize a short pulse power divider (PD). The NED matrix is obtained directly from the time domain port signals, which describes the performance of the short pulse networks comprehensively and compactly. Frobenius norm of the difference between the non-optimal and the optimal NED matrix is used as the objective function in the optimization. A short pulse PD is optimized using the proposed NED matrix based objective function and then fabricated. The feasibility and effectiveness of the NED matrix based objective function are validated by the optimization procedure and the measured results of the short pulse PD.

关键词： Euclidean distance matrix objective function optimization power divider (PD) short pulse time domain

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FUZZY IDENTIFICATION METHOD BASED ON A NEW objective function

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Chinese Journal of Aeronautics 2000年第3期13卷 162-166页

作者：王宏伟贺汉根黄柯棣 Dept. of Automatic Control Natl. Univ. of Defense Technology Changsha 410073 China

A method of fuzzy identification based on a new objective function is proposed. The method could deal with the issue that input variables of a system have an effect on the input space while output variables of the system do not exert an influence on the input space in the proposed objective functions of fuzzy clustering. The method could simultaneously solve the problems about structure identification and parameter estimation; thus it makes the fuzzy model become optimal. Simulation example demonstrates that the method could identify non linear systems and obviously improve modeling accuracy.

关键词： objective function fuzzy clustering fuzzy identification non linear systems

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The role of an objective function in the mathematical modelling of wide-angle X-ray diffraction curves of semi-crystalline polymers

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ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES 2021年第6期77卷 534-547页

作者： Rabiej, Malgorzata Rabiej, Stanislaw Univ Bielsko Biala Fac Mat Civil & Environm Engn Willowa 2 PL-43309 Bielsko Biala Poland

To decompose a wide-angle X-ray diffraction (WAXD) curve of a semi-crystalline polymer into crystalline peaks and amorphous halos, a theoretical best-fitted curve, i.e. a mathematical model, is constructed. In fitting the theoretical curve to the experimental one, various functions can be used to quantify and minimize the deviations between the curves. The analyses and calculations performed in this work have proved that the quality of the model, its parameters and consequently the information on the structure of the investigated polymer are considerably dependent on the shape of an objective function. It is shown that the best models are obtained employing the least-squares method in which the sum of squared absolute errors is minimized. On the other hand, the methods in which the objective functions are based on the relative errors do not give a good fit and should not be used. The comparison and evaluation were performed using WAXD curves of seven polymers: isotactic polypropylene, polyvinylidene fluoride, cellulose I, cellulose II, polyethylene, polyethylene terephthalate and polyamide 6. The methods were compared and evaluated using statistical tests and measures of the quality of fitting.

关键词： polymers diffraction curves absolute error relative error objective function mathematical modelling

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Towards a reliable objective function for multiple sequence alignments

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JOURNAL OF MOLECULAR BIOLOGY 2001年第4期314卷 937-951页

作者： Thompson, JD Plewniak, F Ripp, R Thierry, JC Poch, O ULP Inst Genet & Biol Mol & Cellulaire Lab Biol & Genom Struct CNRSINSERM F-67404 Illkirch Graffenstaden France

Multiple sequence alignment is a fundamental tool in a number of different domains in modem molecular biology, including functional and evolutionary studies of a protein family, Multiple alignments also play an essential role in the new integrated systems for genome annotation and analysis. Thus, the development of new multiple alignment scores and statistics is essential, in the spirit of the work dedicated to the evaluation of pairwise sequence alignments for database searching techniques. We present here norMD, a new objective scoring function for multiple sequence alignments. NorMD combines the advantages of the column-scoring techniques with the sensitivity of methods incorporating residue similarity scores. In addition, norMD incorporates ab initio sequence information, such as the number, length and similarity of the sequences to be aligned. The sensitivity and reliability of the norMD objective function is demonstrated using structural alignments in the SCOP and BAliBASE databases. The norMD scores are then applied to the multiple alignments of the complete sequences (MACS) detected by BlastP with E-value < 10, for a set of 734 hypothetical proteins encoded by the Vibrio cholerae genome. Unrelated or badly aligned sequences were automatically removed from the MACS, leaving a high-quality multiple alignment which could be reliably exploited in a subsequent functional and/or structural annotation process. After removal of unreliable sequences, 176 (24%) of the alignments contained at least one sequence with a functional annotation. 103 of these new matches were supported by significant hits to the Interpro domain and motif database. (C) 2001 Academic Press.

关键词： bioinformatics sequence alignment objective function alignment quality analysis genome analysis

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COFFEE: An objective function for multiple sequence alignments

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BIOINFORMATICS 1998年第5期14卷 407-422页

作者： Notredame, C Holm, L Higgins, DG European Bioinformat Inst EMBL Outstn Cambridge CB10 1SD England Natl Univ Ireland Univ Coll Cork Dept Biochem Cork Ireland

Motivation: In order to inn-ease rite accuracy of multiple sequence alignments, we designed a new strategy for optimizing multiple sequence alignments by genetic algorithm. We named it COFFEE (Consistency based objective function For alignmEnt Evaluation). The COFFEE score reflects the level of consistency between a multiple sequence alignment and a library containing pairwise alignments of the same sequences. Results: We show that multiple sequence alignments can be optimized for their COFFEE score with the genetic algorithm package SAGA. The COFFEE function is tested on 11 test cases made of structural alignments extracted from 3D ali. These alignments are compared to those produced using five alternative methods. Results indicate that COFFEE outperforms the other methods when the level of identity between the sequences is low. Accuracy is evaluated by comparison with the structural alignments used as references. We also show that the COFFEE score can be used as a reliability index on multiple sequence alignments. Finally, we show that given a library of structure-based painwise sequence alignments extracted fi-om FSSP, SAGA cart produce high-quality multiple sequence alignments. The main advantage of COFFEE is irs flexibility. With COFFEE, any method suitable for making pairwise alignments can be extended to making multiple alignments.

关键词： .comparison designed pairwise structural alignments package accuracy extracted optimizing optimized genetic algorithm multiple sequence alignment test cases objective function FSSP COFFEE an objective COFFEE score level of consistency COFFEE function

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Selecting the objective function during the inverse identification of the parameters of a material model of concrete

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FRATTURA ED INTEGRITA STRUTTURALE 2017年第39期11卷 7-16页

作者： Hokes, F. Kala, J. Brno Univ Technol Fac Civil Engn Veveri 331-95 Brno 60200 Czech Republic

Selecting the correct objective function is the critical precondition for a successful optimization task. The validity of this condition is also required when optimization algorithms are needed for the inverse identification of the unknown parameters of nonlinear material models of concrete, where experimentally measured load-displacement curves can be conveniently applied. In such cases, the objective function expressions can be formulated as the difference between the functional values of the curves or via comparing the characteristic features, which comprise the area under the curve and also the maximum functional value. The proposed article brings a study of the influence of the different formulations of the objectives functions to achieving optimum in the inverse analysis using genetic algorithm. The numerical part of the study was performed in the ANSYS computational system with use of multiPlas library of elasto-plastic material models from which the model based on formulations of Menetrey and Willam was chosen.

关键词： Identification objective function RMSE Optimization Sensitivity analysis

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Design of a load balancing objective function for RPL

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JOURNAL OF HIGH SPEED NETWORKS 2024年第3期30卷 297-319页

作者： Elmahi, M. Y. Osman, N. I. M. Sudan Univ Sci & Technol Khartoum Sudan

Routing protocols for Internet of Things (IoT) play a major role in the performance of the network. The standard Routing Protocol for Low-Power and Lossy Networks (RPL) suffers from a number of limitations including congestion of higher-level nodes and unbalanced topology. This paper proposes a novel objective function called Load Balanced Minimum Rank with Hysteresis objective function (LB_MRHOF), which assigns child nodes to the most suitable parent in the topology. The objective function utilizes a weight of the Expected Transmission Count (ETX) and number of children to calculate the Composite ETX and Number of Children (CENOC) which estimates the load on each node. The attained CENOC is used to select the optimum parent for each node in the topology, where nodes with high CENOC are avoided in the parent selection process. The proposed objective function has been evaluated under random and hierarchical network topologies. In addition, the evaluation has investigated the influence of the number of nodes by testing for small, medium and large-scale networks. Results have shown that the proposed objective function outperforms MRHOF, OF_FUZZY and OF-EC in terms of Packet Delivery Ratio (PDR) and reduces nodal hop-count under all tested scenarios, with no compromise in energy consumption. They have also revealed that the best performance achieved by LB_MRHOF is attained under large-scale networks. The resulting network topology which is formed by the proposed objective function has shown improved balance and more depth.

关键词： Internet of Things RPL objective function Load Balance ETX

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A novel of fuzzy PSS based on new objective function in multimachine power system

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COMPLEXITY 2016年第6期21卷 288-298页

作者： Akbarimajd, Adel Yousefi, Nasser Univ Mohaghegh Ardabili Dept Elect Engn Fac Engn Ardebil Iran Islamic Azad Univ Ardabil Branch Young Researchers & Elite Club Ardebil Iran

This article proposed a new control strategy based on Takagi-Sugeno fuzzy model for deceasing the power system oscillation. This controller is based on the parallel distributed compensation structure, the stability of the whole closed-loop model is provided using a general Lyapunov-Krasovski functional. Also, in this article, a new objective function has been considered to test the proposed Fuzzy Power System Stabilizer in different load conditions which increase the system damping after the system undergoes a disturbance. So, for testing the effectiveness of the proposed controller, the damping factor, damping ratio, and a combination of the damping factor and damping ratio were analyzed and compared with the proposed objective function. The effectiveness of the proposed strategy has been used over 16 machine 68 bus power system. The eigenvalue analysis and nonlinear time domain simulation results proof the effectiveness of the proposed method. (c) 2015 Wiley Periodicals, Inc. Complexity 21: 288-298, 2016

关键词： TS fuzzy controller fuzzy power system stabilizer multimachine power system objective function

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THE USE OF GENERALIZED CELL-SURVIVAL DATA IN A PHYSIOLOGICALLY-BASED objective function FOR HYPERTHERMIA TREATMENT PLANNING - A SENSITIVITY STUDY WITH A SIMPLE TISSUE MODEL IMPLANTED WITH AN ARRAY OF FERROMAGNETIC THERMOSEEDS

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INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS 1994年第4期30卷 929-943页

作者： TOMPKINS, DT VANDERBY, R KLEIN, SA BECKMAN, WA STEEVES, RA PALIWAL, BR UNIV WISCONSIN DEPT MECH ENGNMADISONWI 53792 UNIV WISCONSIN DEPT HUMAN ONCOLMADISONWI 53792

Purpose: A physiologically based objective function for identifying a combination of ferromagnetic seed temperatures and locations that maximizes the fraction of tumor cells killed in pretreatment planning of local hyperthermia. Methods and Materials: An objective-function is developed and coupled to finite element software that solves the bioheat transfer equation. The sensitivity of the objective function is studied in the optimization of a ferromagnetic hyperthermia treatment. The objective function has several salient features including (a) a physiological basis that considers increasing the fraction of cells killed with increasing temperatures above a minimum therapeutic temperature (T-min,T-thera), (b) a term to penalize for heating of normal tissues above T-min,T-thera, and (c) a scalar weighting factor (gamma) that has treatment implications. Reasonable estimates for gamma are provided and their influence on the objective function is demonstrated. The cell-kill algorithm formulated in the objective function is based empirically upon the behavior of published hyperthermic cell-survival data. The objective function is shown to be independent of normal tissue size and shape when subjected to a known outer-surface, thermal boundary condition. Therefore, fractions of cells killed in tumors of different shapes and sizes tan be compared to determine the relative performance of thermoseed arrays to heat different tumors. Results: In simulations with an idealized tissue model perfused by blood at various rates, maxima of the objective function are unique and identify seed spacings and Curie-point temperatures that maximize the fraction of tumor cells killed. In ferromagnetic hyperthermia treatment planning, seed spacing can be based on maximizing the minimum tumor temperature and minimizing the maximum normal tissue temperature. It is shown that this treatment plan is less effective than a plan based on seed spacings that maximize the objective function. Conclusions:

关键词： FERROMAGNETIC HYPERTHERMIA TREATMENT PLANNING FINITE ELEMENT METHOD THERMAL MODELING objective function CELL SURVIVAL

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