مقدمة في المجلة
علمی
به مجله تخصصی ریاضی خوش آمدید.
نویسندگان عزیز آگاه باشند که نام مجله به
Theory of Approximation and Applications
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المقالات الأكثر مشاهدة
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1 - An extension of stochastic differential models by using the Grunwald-Letnikov fractional derivative
Mohammad Ali Jafari Narges Mousaviyالعدد 1 , المجلد 16 , زمستان 2022Stochastic differential equations (SDEs) have been applied by engineers and economists because it can express the behavior of stochastic processes in compact expressions. In this paper, by using Grunwald-Letnikov fractional derivative, the stochastic differential model أکثرStochastic differential equations (SDEs) have been applied by engineers and economists because it can express the behavior of stochastic processes in compact expressions. In this paper, by using Grunwald-Letnikov fractional derivative, the stochastic differential model is improved. Two numerical examples are presented to show efficiency of the proposed model. A numerical optimization approach based on least square approximation is applied to determine the order of the fractional derivative. Numerical examples show that the proposed model works better than the SDE to model stochastic processes with memory. تفاصيل المقالة -
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2 - Constacyclic Codes over Group Ring (Zq[v])/<v^q-v>G
Alireza Soleimaniالعدد 1 , المجلد 15 , زمستان 2021Recently, codes over some special finite rings especially chain rings have been studied. More recently, codes over finite non-chain rings have been also considered. Study on codes over such rings or rings in general is motivated by the existence of some special maps calle أکثرRecently, codes over some special finite rings especially chain rings have been studied. More recently, codes over finite non-chain rings have been also considered. Study on codes over such rings or rings in general is motivated by the existence of some special maps called Gray maps whose images give codes over fields. Quantum error-correcting (QEC) codes play a crucial role in protecting quantum information. The construction of quantum codes via classical codes over 2 F was first introduced by Calderbank and Shor [4] and Steane [13] in 1996. This method, known as CSS construction, has received a lot of attention and it has allowed to find many good quantum stabilizer codes. Later, construction of quantum codes over larger alphabets from classical linear codes over q F has shown by Ketkar et al. in [10]. One direction of the main research in quantum error correction codes is constructing quantum codes that have large minimum distances [9] for a given size and length. In [14], based on classical quaternary constacyclic linear codes, some parameters for quantum codes are obtained. In [8, 9], respectively based on classical negacyclic and constacyclic linear codes some parameters for quantum MDS codes are presented. In this work, we determine self-dual and self-orthogonal codes arising from constacyclic codes over the group ring(Zq[v]/G تفاصيل المقالة -
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3 - Application of Box-Behnken Method for Optimization and Modeling of 1,5-Benzodiazepine Production Reaction by CuFe2O4/Clinoptilolite Nanocatalyst
Nazanin Gholamrezaeenya Kazem Mahanpoor Keivan Ghodrati Azam Majani Masoomeh Abdoli-Senejaniالعدد 1 , المجلد 17 , بهار 2024Abstract. In this study, the Box-Behnken design (BBD) was used in the response surface method (RSM) to investigate the modeling and optimization parameters in the synthesis of a 1,5-Benzodiazepine. This method was used to optimize the influencing factors in the synthesi أکثرAbstract. In this study, the Box-Behnken design (BBD) was used in the response surface method (RSM) to investigate the modeling and optimization parameters in the synthesis of a 1,5-Benzodiazepine. This method was used to optimize the influencing factors in the synthesis process of this material, including the amount of nanocatalyst, temperature, and reaction time. The obtained mathematical model was analyzed by variance analysis. To determine the optimal conditions, graphs of graphic counters and response levels were used. The results showed that the amount of nanocatalyst has the greatest effect on the synthesis reaction of 1.5 Benzodiazepines. The maximum efficiency for the synthesis of the product was determined at a temperature of 283 K, the amount of CuFe2O4/Clinoptilolite = 6 grams per liter and time = 60 minutes. تفاصيل المقالة -
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4 - Balaban Index of C4C8(S) Nanotubes
Abbas Heydariالعدد 2 , المجلد 14 , بهار 2020where m is the number of edges, μ is the cyclomatic number of G, d(u) is thesum of distances between vertex u and all of the vertices of G, and the summationgoes over all edges from the edge set E(G). In this paper we obtain amethod for calculating the Balaban index أکثرwhere m is the number of edges, μ is the cyclomatic number of G, d(u) is thesum of distances between vertex u and all of the vertices of G, and the summationgoes over all edges from the edge set E(G). In this paper we obtain amethod for calculating the Balaban index of nanotubes which have square andoctagon structure and denoted by C4C8(S) nanotubes. تفاصيل المقالة -
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5 - Entropy Method to Analyze the Impact of Eco-Friendly Consumer Attitudes on Green Brand Intention: Apple Brand Consumers
Maryam Ghiasabadi Farahani Peyman Ghafari Ashtiani Majid Shadmandالعدد 2 , المجلد 15 , بهار 2021The present study seeks to investigate the impact of environmental friendly consumers' attitude on green brand intention. Based on literature review and identified gaps the study proposed an integrated theoretical model. To empirically test the proposed model this study أکثرThe present study seeks to investigate the impact of environmental friendly consumers' attitude on green brand intention. Based on literature review and identified gaps the study proposed an integrated theoretical model. To empirically test the proposed model this study collected data from 384 individual customers of questionnaire survey method. The study utilized Structural Equation Modeling (SEM) technique to statistically analyses measurement and structural models. The results show the positive effect of variables (environmental concern, attitude to environment, green brand quality and empirical satisfaction on green brand) on green purchase intention and negative impact of variable (environmental knowledge) on green purchase intention is. تفاصيل المقالة -
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6 - Imprecise Revenue Efficiency under Productivity Change
Mohsen Rostamy-Malkhalifehالعدد 2 , المجلد 15 , بهار 2021Traditional data envelopment analysis (DEA) models evaluate the performance of decision-making units (DMUs) with the exact data and do not assume evaluation in the condition that the environment is uncertain. When some data are unknown, such as interval data, the DEA mo أکثرTraditional data envelopment analysis (DEA) models evaluate the performance of decision-making units (DMUs) with the exact data and do not assume evaluation in the condition that the environment is uncertain. When some data are unknown, such as interval data, the DEA model is called imprecise DEA (IDEA). In this paper, we develop a new Malmquist productivity index(MPI) for dealing with interval data in DEA. Then, an approach for measuring the Malmquist productivity index using revenue efficiency is extended, too. The capabilities of the presented approach are shown by means of an example. تفاصيل المقالة -
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7 - PROVIDING A MODEL FOR REDUCING DRUG SUPPLY CHAIN COST WITH USING DESIGN OF EXPERIMENTS; CASE STUDY: IMAM ALI (AS) CARDIOVASCULAR HOSPITAL OF KERMANSHAH CITY
Mohammad Ehsanifar Parastu Farhaadi Sina Shalibeikالعدد 1 , المجلد 15 , زمستان 2021Abstract:The objective of this study was to optimize the costs of health logistics in the studied system and to cope with the planned budget cuts for health and treatment for the studied system. The question was that; what was the most influential factor in increasing c أکثرAbstract:The objective of this study was to optimize the costs of health logistics in the studied system and to cope with the planned budget cuts for health and treatment for the studied system. The question was that; what was the most influential factor in increasing costs, which reduced the planned healthcare budget concerning the studied system? At first a number of variables were defined. Using one-way analysis of variance, we examined the costs in the 12 months of 2016, whether the total costs in the 12 months of 2016 were equal or not. Then, using the Fisher test investigated among the 12 months, which month (s) were the most expenditure; after that, it is important to determine what has caused this high costs. Finally, we presented a model for optimizing and reducing costs. For these cases, the design of experiments and the full factorial design were used. The results of one-way ANOVA showed that the total amount of costs in the 12 months of 2016 were not equal. Fisher test showed that the second and fifth months had the highest cost; also, design of experiments with full factorial method showed that the cost-increasing factors were orders, stockroom and demand, respectively. تفاصيل المقالة -
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8 - Deep Learning: Concepts, Types, Applications, and Implementation
Fereshteh Aghabeigi Sara Nazari Nafiseh Osati Iraqiالعدد 2 , المجلد 16 , بهار 2022Today, deep learning has attracted attention in various scientific and non-scientific fields. Deep learning is a branch of machine learning that simulates the human brain for various applications like recognizing voice, face, handwriting, identifying kinship, image proc أکثرToday, deep learning has attracted attention in various scientific and non-scientific fields. Deep learning is a branch of machine learning that simulates the human brain for various applications like recognizing voice, face, handwriting, identifying kinship, image processing, and etc. In deep learning, a set of representation algorithms is used to model high-level abstract concepts through learning at different levels and layers. Deep learning has become popular due to its capabilities like automatic feature extraction, high extendibility, and wide application in different fields. In this paper, it is tried to describe different deep learning models and architectures, how they are trained, and the required hardware and software structures. تفاصيل المقالة -
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9 - C*-Algebra-Valued Fuzzy Metric Spaces in Coupled Fixed Point with Applications
Samuel Anikiالعدد 2 , المجلد 16 , بهار 2022Coupled fixed point has been a major area of research interest in the field of fixed point theory. This work establishes coupled fixed point for C*-algebra-valued contractions in fuzzy metric spaces. Also, application in integral equations to back up our claim was given أکثرCoupled fixed point has been a major area of research interest in the field of fixed point theory. This work establishes coupled fixed point for C*-algebra-valued contractions in fuzzy metric spaces. Also, application in integral equations to back up our claim was given. The results of our findings are an improvement to some existing works in the literature تفاصيل المقالة -
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10 - The investigation of loss aversion in investment companies in Tehran stock exchange
Zahra Madahi Roya Derakhshaniالعدد 1 , المجلد 15 , زمستان 2021Loss aversion, the principle that losses loom larger than gains, is among the most widely accepted ideas in the social sciences. Behavioral finance is a division of finance science that investigates the behavior of the financial markets regarding their psychology. Loss أکثرLoss aversion, the principle that losses loom larger than gains, is among the most widely accepted ideas in the social sciences. Behavioral finance is a division of finance science that investigates the behavior of the financial markets regarding their psychology. Loss aversion is among the behavioral effects of the investors that have bad consequences and leads to a decrease in the portfolio return and makes the potential of receiving benefit limited. considering the salience of the role of the investing companies in selecting the optimal investment portfolio in the stock exchange of Tehran. Investors unfamiliar with financial markets and investor retailers have reduced their risk by turning to investment firms and expecting them to attract the best possible returns on their investments. The current research has investigated the disposition effect of loss aversion in the portfolio of 50 investment companies that includes 1100 companies for 3 succeeding years from 2017 to 2019 monthly. In order to categorize the data and define the variables and analyze them, two software has been used "Eviews" and "Excel". The results of the research confirm that there exists a disposition effect of the loss aversion in the investment companies of the stock exchange of Tehran. تفاصيل المقالة
