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Open Access
Intuitionistic fuzzy and hesitant fuzzy sets based time series forecasting methods
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-12) Bisht, Kamlesh; Sanjay Kumar
In the present research work, various time series forecasting methods using intuitionistic fuzzy, hesitant fuzzy and dual hesitant fuzzy sets are developed to address issue of non stochastic uncertainty and non-stochastic hesitation. These methods are presented in form of various models. Model [1] and Model [4] are computational algorithm based higher order fuzzy time series forecasting models which are based on intuitionistic fuzzy and hesitant fuzzy respectively. Model [2] and Model [3] use hesitant fuzzy set to handle hesitancy in fuzzy time series forecasting. In the present research work, methodology of hesitant fuzzy time series forecasting method is also developed and presented in Model [5]. Model [6] is intuitionistic fuzzy time series forecasting model which is based on dual hesitant fuzzy set. Model [2], Model [3], Model [5] and Model [6] use max-min composition operation. Performance of these developed models over existing fuzzy time series and intuitionistic fuzzy time series forecasting methods is verified by implementing them on two time series data of University of Alabama and SBI share price. The outperformance of all models is tested using RMSE and AFER error measures. Validity of the developed models id tested using correlation coefficients, tracking signal, evaluation parameter and performance parameters. Superiority of developed models is also tested using two tailed t-test at the confidence level 1% and 5%. In forecasting enrollments of University of Alabama, the performance of Model [4] in terms of both RMSE and AFER is found better than model [1], Model [2], Model [3], Model [5] and Model [6]. In forecasting share prices of SBI, the performance of Model [6] in terms of both RMSE and AFER is found better than Model [1], Model [2], Model [3], Model [4] and Model [5]. In forecasting enrollments of University of Alabama, Model [1] outperforms over Model [2] but its performance is equally good as of Model [3], Model [4], Model [5] and Model [6]. Model [2] outperforms over Model [4] and Model [5] but its performance is good as Model [3] and Model [6]. Model [3] performs equally good as Model [4], Model [5] and Model [6]. Model [4] outperforms over Model [6] but its performance is good as Model [5]. Model [5] is equally good in performance as the Model [6]. In forecasting SBI share prices, Model [1] outperforms over Model [2], Model [3] but its performance is good as Model [4], Model [5]. Model [2] outperforms over Model [4], Model [5] and Model [6] but its performance is good as Model [3]. Model [3] outperforms over Model [4], Model [5] and Model [6]. Model [4] performed equally good as Model [5] and Model [6]. Model [5] outperforms over Model [6]. All developed models not only handle the non-stochastic uncertainty and hesitation but also enhance the accuracy in forecasted enrollments and financial time series data of SBI share price.
Open Access
On reliability modeling of complex systems: signature and fuzzy based expressions
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Akshay Kumar; Singh, S.B.
The present research study is based on the development of reliability models with the help of UGF and fuzzy sets. In this study, eight different reliability models have been developed. Model-1 studies the reliability characteristic of sliding window coherent system which consists of n number of components connected in parallel configuration using UGF. Model-2 discusses the signature reliability of complex and k-out-of-n coherent system with the help of reliability functions. Model-3 focuses on reliability metrics of a sliding window coherent system in case of multiple failures. Model-4 deals with a linear multi-state sliding window coherent system which generalizes the consecutive k-out-of-r-from-n:F system in multi-state case. All the aforesaid models evaluated the signature, MTTF, Barlow-Proschan index and expected cost etc. Model-5 studies the reliability of two states consecutive sliding window system consisting of generalized linear multi-state sliding window system having m consecutive independent and identically distributed components. Model-6 introduces and studies the intervalvalued reliability of to 2-out-of-4 system with the help of reliability function using UGF. The considered system consists of 2 numbers of components connected in series. Model7 investigates the intuitionistic fuzzy reliability measure of a linear (circular) consecutive k-out-of-n:F system of non-identical elements with the Weibull lifetime distribution and Markov process. Model-8 deals with series, parallel and consecutive k-out-of-n: F systems, using triangular hesitant fuzzy number and Weibull distribution.
Open Access
Numerical study of some flow problems in nanofluid
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-04) Pandey, Alok Kumar; Manoj Kumar
In the present study numerical scheme have been employed to analyze the boundary layer flow, heat and mass transfer flow past a nanofluid due to various geometries. The flow around immersed bodies in Newtonian and Non-Newtonian fluid streams are commonly encountered in many studies in medical arena, geophysics, mechanical engineering, hydrodynamics, chemical engineering and ocean engineering etc. The boundary layer flow of nanofluid around bodies of various geometries such as wedge, stretching cylinder, stretching surface, parallel plate and divergent/convergent channel have been discussed. The different flow conditions involve various physical phenomenon such as magnetic effect, velocity slip effect, thermal slip effect, suction/injection, Brownian motion and thermophoresis effects, porosity, buoyancy effect, heat generation/absorption, thermal radiation, chemical reaction, viscous dissipation, Ohmic dissipation and nanoparticle volume fraction etc., have been investigate their impact on profiles of nanofluid for velocity, temperature and concentration. Further, their effects on skin friction coefficient, Nusselt and Sherwood number are studied and discussed in details. The pre requisites of essential concepts have been involved in introduction section. The Lie group transformation and similarity transformation have been employed to altered the fundamental equations into similar dimensionless form and then after Runge-KuttaFehlberg scheme of fourth fifth order together with shooting technique is applied to solve them with the aid of standard MATLAB package. To check the validity of our code we have contrasted our results with those reported in previous literature. This investigation declared that boundary layer flow and heat transfer analysis may be performed in large industrial significance including industrial cooling applications as smart fluids, in nuclear reactors, automotive applications, electronic applications and biomedical applications. The MHD nanofluid flow in electrical conducting fluid can manage the rate of cooling and the required class of products can be obtained. The present study may support in the fields of applied science and also for the researchers working in the field of miniaturized technology, medical science and mechanical engineering etc.
Open Access
Analysis and extension of some secret handshake schemes
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-03) Kulshrestha, Preeti; Arun Kumar
Trust establishment during the secure communication is very important as trust establishment become delicate when it involves the exchange of sensitive secret information. Recently introduce secret handshake primitive tackled this problem, which allows two user to authenticate each other secretly and derive a shared common session key only if they both belong to the same organization, otherwise they learn nothing about each other. In this thesis, we present four secret handshake protocols. At first, we focus on secret handshake based on ElGamal and DSA signature and introduce two secret handshake schemes based on variations of DSA signature which are secure under random oracle model. Then we concentrate on ZSS signature and construct two schemes with two different features, one is secret handshake with dynamic matching and another is secret handshake with unlinkability. Both the schemes are secure under bilinear inverse Diffie-Hellman assumption. We also cryptanalysis an existing scheme of unlinkable secret handshake. All developed protocols can be helpful in real life problems in which two entities wish to communicate secretly and want to establish a session key without being observed or detected
Open Access
A study of reliability models based on fuzzy set theoretic approach
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-01) Pawan Kumar; Singh, S.B.
The present work consists of five chapters. A brief summary of these chapters is given below. Chapter one of the thesis is purely introductory in nature and contains history related to reliability theory with several definitions of different reliability tools which are often used in the study of reliability theory. Some different probabilistic distributions are also introduced in this chapter. This chapter also discusses the fundamental concepts of fuzzy set theory and gives some application of fuzzy set theory (FST) to reliability engineering. The chapter two contains review of literature pertaining to classical reliability analysis techniques of different researchers and recent research papers related to reliability theory, fuzzy theory and fuzzy reliability theory. Chapter three describes the different methodology of reliability evaluation of different complex systems using interval-valued intuitionistic fuzzy set, generalized trapezoidal intuitionistic fuzzy number, different types of level ( ߩ, ߣ ) interval-valued fuzzy number, and different types of conflicting bifuzzy failure rates. Concept of intuitionistic fuzzy Weibull lifetime distribution and intuitionistic fuzzy random lifetimes are also discussed in this chapter. The reliability and mean time to failure (MTTF) of the different systems are also evaluated. In chapter four some numerical examples are presented to illustrate how to calculate the fuzzy reliability using different methods under different fuzzy environments. The results obtained from the examples illustrated in this research also support the traditional facts of the system reliability. We can conclude from the present study that the proposed methods have no restrictions and it is applicable in situations where there are subjectivity, imprecision, uncertainty, ambiguity and hesitancy. In the final chapter, conclusions and future works are summarized.
Open Access
Reliability of systems under different fuzzy environments
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2015-07) Deepak Kumar; Singh, S.B.
The present work consists of five chapters. A brief summary of these chapters is given below. The chapter one of the theses is purely introductory in nature and contains history related to reliability theory with several definitions of different reliability tools which are often used in the study of reliability theory. This chapter also discusses the fundamental concepts of fuzzy set theory and the need of fuzzy set theory in reliability evaluation. The chapter two contains review of literature which is a detailed survey of previous work done by different researchers and recent research papers related to reliability theory, fuzzy theory and fuzzy reliability theory. In the chapter three, different methods of reliability evaluation of the different systems using rough fuzzy set, intuitionistic fuzzy set, interval-valued intuitionistic fuzzy set, hesitant fuzzy set, trapezoidal fuzzy number and hexagonal fuzzy number have been developed. Some concepts about bifuzzy set and soft fuzzy set also introduced in this chapter. In the chapter four some numerical examples are presented to illustrate how to calculate the fuzzy reliability using different methods under different fuzzy environments. The results obtained from the examples illustrated in this research also support the traditional facts of the system reliability. Some new concepts about characterisations of α-cut in conflicting bifuzzy set theory and some new operations in soft intuitionistic fuzzy sets are also developed. In the final chapter, conclusions and future works are summarized. We can conclude from the present study that the proposed methods have no restrictions and it is applicable in situations where there are subjectivity, imprecision, uncertainty, ambiguity and hesitancy.
Open Access
Reliability assessment of systems using universal generating function in different environments
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-01) Negi, Seema; Singh, S.B.
Due to the complexity of the real life systems it becomes mandatory to evaluate their reliability. Keeping this fact in view, the focus of the present research is on the development of reliability models with the help of UGF and FUGF. This study proposes nine different reliability models. Model 1 deals with the reliability (unreliability) of circular weighted-(n, f,k): G (F) systems with the application of UGF. In this model some conditions on weight are imposed and reliability have been compared. The sensitivity of the considered systems with respect to different parameters has also been examined. Models 2 introduces and analyzes the fuzzy reliability of linear weighted-(n, f, k, m): G (F) systems with the help of UGF and fuzzy exponential distribution. Also after imposing different conditions on weight, the fuzzy reliability and FMTTF of the proposed systems have also been compared. Model 3 focuses on the reliability, MTTF and sensitivity analysis of a complex system which consists of two non repairable subsystems, namely A and B connected in series and parallel, having non identical and independent components, each having different probabilities of success by using UGF. Model 4 studies a non repairable complex system which consists of two subsystems say A and B, connected in series. The subsystems A and B are weighted k-out-of-n: G and weighted l-out-of-m: G configurations respectively. All the components of the subsystems A and B are arranged in parallel. Five prepositions are developed to express the UGF of the proposed system. This study is further extended to evaluate the reliability characteristics such as reliability, MTTF and sensitivity of the proposed system based on these prepositions. Model 5 studies the fuzzy reliability measures of a linear m-consecutive weighted-kout-of-r-from-n: F system. This model provides an algorithim for the evaluation of fuzzy reliability of the proposed system based on application of UGF and fuzzy exponential distribution. It is assumed in the study that failure rate follows GrSTrFN in fuzzy exponential distribution. Further, GrSTrFN and its arithmetic operations are obtained. Model 6 investigates the fuzzy reliability characteristics of fuzzy weighted- k~-outof-n: G (F) system by using fuzzy exponential distribution and UGF. Expressions for fuzzy reliability, FMTTF and their (α, β)-cut have been discussed when systems follow trapezoidal intuitionistic fuzzy exponential distribution. Model 7 introduces and studies the reliability measures of a weighted-((f / (r, s)), k)/(m, n): G system based on UGF and Rayleigh distribution. In this model some prepositions are formed to understand the behaviour of the proposed system with respect to different varying parameters. Model 8 deals with the reliability analysis of a k-out-of-n: G system with redundancy and load sharing components in which load sharing is dependent on failure rates of working components under certain law by using UGF. Further this study presents the new formulas for load sharing in different environments. Model 9 investigates the fuzzy reliability measures of a redundant consecutive fuzzy weighted- k~-out-of-n FMSSs by using the combination of fuzzified stochastic process and FUGF. These systems is made up of n independent, nonidentical and non-repairable MSEs and a cold standby MSE whose state transition rate (failure rate) are provided by the decision makers as TFN. Also the fuzzy weight and fuzzy performance rate of each MSE is taken as TrIFN and TFN respectively. In this study we have developed formulae for FUGF in two cases: with redundancy and without redundancy. By using these expressions, formulae for fuzzy reliability and FMTTF of the proposed systems have been evaluated. Finally two prepositions are developed to count the effect of fuzzy weight k~on the fuzzy reliability and FMTTF of the proposed FMSSs. At last all the developed models are illustrated through numerical examples.
Open Access
Study of some probabilistic and computational methods for fuzzy and intuitionistic fuzzy time series forecasting
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2013-08) Gangwar, Sukhdev Singh; Sanjay Kumar
Time series forecasting in the environment of fuzzy and intuitionistic finds its scope in various branches of sciences and engineering. The present research work mainly focus on development and implementation of fuzzy and intuitionistic fuzzy time series forecasting models. In this study, 6 different models of fuzzy and intuitionistic fuzzy time series forecasting were developed. Model 1, model 2 and model 3 were computational algorithm based higher order fuzzy time series forecasting models. These models were based on multiple partitions which were created using a ratio formula that uses maximum and minimum of time series data. Model 4, model 5 and model 6 used the concept of IFS to include degree of hesitation in time series forecasting. In model 4, the concept of IFS was used in fuzzification process. In model 5, fuzzy sets induced from IFS were used to establish fuzzy logical relations. Model 6 is purely intuitionistic fuzzy time series forecasting model. Both model 4 and model 5 used max-min composition of fuzzy logical relations and model 6 used max-min composition of intuitionistic fuzzy logical relations. All developed models (model 1 to model 6) were implemented on the time series data of enrollments of University of Alabama and share prices of SBI. Results of all forecasting models have been presented graphically to show their trend with actual time series data. Performance analysis of all models has been discussed in terms of MSE and AFE. Time series data of enrollments of University of Alabama were used to show robustness of all models to show their sensitivity towards the unexpected fluctuation in time series data. In forecasting enrollments of University of Alabama, the performance of model 3 in terms of both MSE and AFE is found better than model 1 and model 2. In forecasting share prices of SBI, the performance of model 1 in terms of both MSE and AFE is found better than model 2 and model 3. In forecasting enrollments of University of Alabama, the performance of model 5 in terms of both MSE and AFE is better than other IFS based forecasting models (model 4 and model 6). In forecasting share prices of SBI, the performance of model 6 in terms of MSE is found better than model 4 and model 5 but the performance of model 5 in terms of AFE is found better other model 4 and model 6. Overall, in the case of forecasting the enrollments of University of Alabama, model 3 outperforms than the model 1, model 2, model 4, model 5 and model 6 in terms of MSE and AFE. In terms of MSE and AFE, model 1 outperforms than the model 2, model 3, model 4, model 5 and model 6 in forecasting share prices of SBI. Model 6, intuitionistic fuzzy time series forecasting model and also gives the good performance with respect to other models. The present study may be helpful in research of many forecasting branches as well as in the fields of fuzzy and intuitionistic fuzzy time series forecasting.
Open Access
Performance analysis of wireless communication networks using Queuing models
(G.B. Pant University of Agriculture and Technology, Pantnagar-263145 (Uttarakhand), 2015-07) Ujarari, Chandan Singh; Pal, A.K.
The whole civilization in the world is dependent on wireless technology. The Gradual growth or development of current environment of the people is not possible without communication. As the use of wireless/ mobile devices increases, there is increment in the requirement of the quality of the service for the users. In this study, we have developed a queueing models for wireless communication using ALOHA and OFDMA-ALOHA which is model 1. In this model, we have derived an adaptive algorithm for ALOHA and OFDMA-ALOHA. The performance of developed model has been evaluated in terms of mean access delay for the saturated case of the two MAC Protocols in model 2. The performance of the contention based services via broadcast polling in unsaturated IEEE 802.16 networks with channel errors is studied in systematic way. The essential characteristics of wireless communications are taken into account, such as network congestion, call block, call drop, deterministic burst intervals and arrivals of transmission packets. The PGF of packet delay and arbitrary moments are evaluated by probability generating function. In model 3 we analyze the comparative study of handoff scheme by comparing its performance analysis of priority within a particular channel in wireless systems. The numerical results demonstrate the effectiveness of our analysis framework and the performance gain for performance analysis of wireless communication. The present study may be helpful in applied scientific fields like performance enhancement of video streaming, multipath transmission, OFDMA-ALOHA, broadcasting techniques and how to reduce the call congestions and handoff failure.

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