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Issue Info: 
  • Year: 

    1386
  • Volume: 

    13
Measures: 
  • Views: 

    432
  • Downloads: 

    0
Abstract: 

در این مقاله، شیوه ای جهت انتخاب فضای ویژگیها و کاهش ابعاد، با استفاده از یادگیری تقویتی ارائه می شود. به این منظور از یک سیستم چند عامله اشتفاده شده که در آن عاملهای یادگیرنده می کوشند تا با مواجهه با مساله و همکاری با یکدیگر به یک هدف مشترک، که به دست آوردن مجموعه ای از بهترین ویژگیها میباشد، برسند. یادگیری عاملها به واسطه بررسی میزان تاثیر گروهی از ویژگیها، بر اساس بیشترین جداپذیری که در بین داده ها ایجاد می کنند، با سعی و خطا خواهد بود. این جداپذیری مبتنی بر روش جداپذیری فیشر و استفاده از ضریب همبستگی در جهت بیشینه کردن حداقل فاصله کلاسها می باشد.

Yearly Impact:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Issue Info: 
  • Year: 

    1386
  • Volume: 

    1
Measures: 
  • Views: 

    948
  • Downloads: 

    0
Keywords: 
Abstract: 

در دهه های اخیر، با افزایش چشمگیر وسایل نقلیه و حجم نقل و انتقالات، زمان های سفرهای درون شهری افزایش یافته است. کند شدن شریان توسعه و اقتصاد شهری، افسردگی، کاهش توان فردی، مصرف بسیار زیاد سوخت، افزایش سطح دی اکسید کربن و سایر آلاینده های محیطی، ترافیک را به صورت یک معضل اجتماعی - اقتصادی در آورده است، به گونه ای که مدیریت و کنترل صحیح آن اهمیت زیادی یافته و در دستور کار مسوولین قرار گرفته است.در حال حاضر اکثر سیستم های کنترل ترافیک از قوانین ثابت و از پیش تعیین شده ای استفاده می کنند، که تحت عنوان آیین نامه ها، دارای جامعیت عمومی بوده و کمتر با شرایط و تغییرات محلی سازگارند، در حالیکه، مطالعات جدید نشان می دهد که اتخاذ استراتژی ها به صورت بی درنگ و متناسب با تغییرات محیط، زمان های انتظار در پشت چراغ ها را 5 تا 15 درصد کاهش می دهد.سیستم های کنترل ترافیک به منظور بهبود عملکرد خود می بایست تغییرات تدریجی در محیط ترافیکی را شناسایی کرده، نحوه تغییرات را تخمین زنند، و خود را با آن تطبیق دهند. همچنین اینگونه سیستم ها می بایست قادر به کنترل شرایط غیر قابل پیش بینی نظیر تصادفات نیز بوده، و آنها را به وسیله ابزار ترافیکی (نظیر چراغ های راهنمایی) و همکاری بین آنها کنترل نماید. به منظور طراحی و پیاده سازی چننی عامل هایی روش های یادگیری ماشینی هوشمند انتخاب مناسبی می نماید.این مقاله با ادغام روش های تعمیم و تقریب خطی با داده های اتخاذ شده از حس گرهای متعارف ترافیکی و نیز استفاده از روش یادگیری تقویتی، روشی کارا با بار حافظه ای و محاسباتی کم به منظور کنترل جریان ترافیک ارایه می دهد.

Yearly Impact:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Issue Info: 
  • Year: 

    1395
  • Volume: 

    8
Measures: 
  • Views: 

    695
  • Downloads: 

    0
Abstract: 

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Yearly Impact:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Issue Info: 
  • Year: 

    2018
  • Volume: 

    18
  • Issue: 

    1
  • Pages: 

    388-396
Measures: 
  • Citations: 

    0
  • Views: 

    1114
  • Downloads: 

    0
Abstract: 

In this paper, a robust linear quadratic regulator (LQR) based Reinforcement learning method is designed for a four degree of freedom inverted pendulum. The considered system contains a four degree of freedom inverted pendulum with a concentrated mass at the tip of it. The bottom of inverted pendulum is moved in x-y plane in x and y directions. For tracking control of two angles of inverted pendulum, two plane forces are applied in x and y directions at the bottom of pendulum. The governing equations of the system are derived using the Lagrange method and then a robust linear quadratic regulator (LQR) based Reinforcement learning controller is designed. The inverted pendulum is learned for a range of different angles, different lengths and different masses. The parametric uncertainties are defined as various lengths and masses of inverted pendulum and the disturbances are defined as impact and continuous forces which are applied on the inverted pendulum. After learning, the controller can learn online the system for any arbitrary angle, length, mass or disturbance which are not learned in the defined range. Numerical results show that the good performance of the reinforcement learning controller for the inverted pendulum in the presence of structural and parametric uncertainties, impact and continuous disturbances and sensor noises.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Issue Info: 
  • Year: 

    2012
  • Volume: 

    10
  • Issue: 

    1
  • Pages: 

    40-46
Measures: 
  • Citations: 

    0
  • Views: 

    1796
  • Downloads: 

    0
Abstract: 

Using Information Technology techniques have been increased complication and dynamicity of supply-and-demand systems like auctions. In this paper, we introduce a novel method by applying Reinforcement Learning (RL) price offer as one of the robust methods of agent learning which can be used in interactive conditions with minimum level of information in auction and reverse auction. Negotiation as one of the challengeable and complicated behaviors is caused an agreement on price in auctions. The main aim of our method is maximizing seller’s and customer’s profits. We formulate seller and customer selection in form of two different RL problems. All of the RL parameters like states, actions, and reinforcement function are defined. Also, we describe an experimental method to compare with our proposed method for proving advantages of our method.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

View 1796

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Issue Info: 
  • Year: 

    2019
  • Volume: 

    15
  • Issue: 

    1
  • Pages: 

    50-57
Measures: 
  • Citations: 

    0
  • Views: 

    878
  • Downloads: 

    0
Abstract: 

Introduction: Training deep curriculum learning is a kind of smart agent training in which, first the simple acts, and then, the difficult acts are trained to smart agent. In this study, we proposed a new framework for training deep curriculum learning to defense-based game in particular Dragon Cave. Materials and Methods: Deep reinforcement learning approach with curriculum learning was used to train an intelligent agent in the game Dragon Cave. Curriculum learning paradigm started from simple tasks, and then gradually tried harder ones. Using Proximal Policy Optimization, the intelligent agents were trained in various environments, once in a curriculum-learning environment, and once in an environment without curriculum learning. Then, they started the game in the same environment. Results: The improvement of the agent was observed with deep curriculum reinforcement learning. Conclusion: It seems that the deep curriculum reinforcement learning increases the rate and the quality of intelligent agent training in complex environment of strategic games.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Issue Info: 
  • Year: 

    1387
  • Volume: 

    14
Measures: 
  • Views: 

    588
  • Downloads: 

    0
Abstract: 

یکی از مسایل مطرح در محیط های گرید، مدیریت بار منابع و موازنه بار در سیستم می باشد. ناهمگونی منابع، پویایی محیط گرید و تنوع کارهای ورودی به گرید از جمله مسایلی هستند که توسعه الگوریتم های بهینه موازنه بار را با مشکل مواجه می سازند. در این مقاله با مدل کردن محیط گرید بعنوان یک محیط یادگیری تقویتی و اعمال الگوریتم یادگیری تقویتی SARSA (l) در تصمیمی گیری ها، روشی برای تخصیص کارها به منابع و موازنه بار ارایه داده ایم. در این روش تخصیص کارهای ورودی به منابع بگونه ای است که سطح مطلوبی از توازن بار در گرید حاصل می شود. روش ارایه شده، در یک محیط گرید واقعی مورد آزمایش قرار گرفته و نتایج تجربی نشان دهنده کارایی مناسب و تطبیق پذیری این روش با شرایط پویای گرید می باشد.

Yearly Impact:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Issue Info: 
  • Year: 

    2022
  • Volume: 

    12
  • Issue: 

    1
  • Pages: 

    64-75
Measures: 
  • Citations: 

    0
  • Views: 

    308
  • Downloads: 

    0
Abstract: 

Introduction In developed societies, residential customers use high-level appliances. The progress in the smart grids and the internet of things have eased the way for home energy management to schedule controllable appliances. Looking to demand increment, demand response strategies aiming at energy management, to achieve goals such as demand reduction and improving reliability, has received attention. A deep review of the existing literature shows the notable efforts put into optimizing the home energy management problem through classic and meta-heuristic optimization algorithms such as game theory, genetic algorithm, and PSO. But, it is worth saying that these algorithms are not pragmatic due to the inherent nature of the home energy management problem. To be more precise, as the environment of the problem changes continuously, these algorithms fail to solve the problem. Hence, some essential assumptions such as considering fixed scenarios are presumed in previous works to enable the conventional algorithm to solve the problem. This is while machine learning addresses this issue by extracting the main features from input data and constructing a general description of the environment. Implementation of machine learning-based algorithms to a home energy management problem requires smart appliances. Hence, in the case of having a smart home, taking the advantage of artificial intelligence for energy management would be feasible and useful. It should be noted that electricity cost reduction can make the demand response program inviting, where customer satisfaction is taken into consideration. Accordingly, customer satisfaction should be considered in the problem formulation. Regarding the mentioned issues, lately, with the remarkable progress in machine learning, novel algorithms evolved for solving optimal decision-making problems such as demand response. Machine learning can be categorized into three main categories, namely supervised learning, unsupervised learning, and reinforcement learning (RL). Among them, reinforcement learning has shown notable performance in decision-making problems. Q-Learning is a model-free RL algorithm that solves nonlinear problems through estimating and maximizing the cumulative reward, triggered by decided actions. The fundamental idea of this algorithm is to identify the best action in each situation. This paper aims to provide a day-ahead demand response program for a smart home. It is done by specifying the quantity of the energy consumption of each appliance, aiming to reduce the electricity cost and user dissatisfaction. In this respect, it is presumed that the smart home is equipped with smart appliances. Moreover, smart meters are installed on appliances to monitor the statuses and receive the command signals from the devices at each hour. These appliances can be divided into three categories, non-responsive, time-shiftable, and controllable loads. Dishwasher and washing machine as time-shiftable loads, EV, air conditioner, and lighting system as controllable loads, and TV and refrigerator as non-responsive loads are taken into account. All in all, we recommend an advanced home energy management system proposing the following contributions: i) Proposing a day-ahead multi-agent Q-Learning method to minimize the electricity cost. ii) Proposing a satisfaction-based framework, which employs a precise model of the customer dissatisfaction functions (i. e., thermal comfort, battery degradation, and desirable operation period). Materials and methods In this paper, a multi-agent Q-Learning approach is used to solve the home energy management for a smart home. Q-learning is a popular model-free algorithm among reinforcement learning algorithms, due to the fact that its convergence is proven, and it is feasible to implement, as well. In order to deploy Q-Learning on a home energy management system, first of all, smart home should be formed as a Markov decision process. A Markov decision process consists of four fundamental parameters namely, state, action, reward, and transition probability matrix. Afterward, an agent is trained through experiencing a specific state, taking an action, transition to a new state, and calculating the cumulative reward. By doing so, after visiting a considerable number of states and taking diverse decisions, it will learn gradually to select the optimum action whatever the state is. Another fundamental aspect of this paper is the proposed approach to take customer satisfaction into account. In this paper, a non-linear thermal comfort model, non-linear desirable operation period model, and linear battery degradation model are deployed to consider the customer dissatisfaction, precisely. It should be noted that all simulations have been implemented by python 3. 6 programming language without making use of any commercial solver. Result Various case studies have been designed to verify the effectiveness of the proposed method. Scenario 1 is designed to simulate the behavior of a smart home associated with a random manner of energy usage. Scenario 2 is designed to verify the effectiveness of the proposed home energy management system, where Q-Learning is conducted. In this case, battery degradation is overlooked. Scenario 3 is similar to the previous one, where battery degradation is also taken into consideration. Comparing the obtained results indicates that the proposed algorithm has successfully reduced the electricity bill by 31. 3% and 24. 8% in scenarios 2 and 3, respectively. It is worth saying that customer satisfaction is not violated in mentioned scenarios. Furthermore, in order to evaluate the effect of thermal comfort on the electricity bill, another case study is deployed, where the thermal comfort coefficient is decreased to smaller magnitudes. As expected, the less thermal comfort coefficient, the less electricity bill. The reason behind this is that having a lower thermal comfort coefficient leads to less importance of temperature control compared to the electricity bill. Conclusion This paper proposed a method for home energy management, regarding minimizing the electricity bill and user discomfort. In this paper, a multi-agent reinforcement learning via Q-Learning is used to make optimal decisions for home appliances, which are categorized into non-shiftable loads, time-shiftable loads, and controllable loads. Comparing to classic optimization methods, the proposed approach in this paper is capable of modeling more appliances and solving complex problems, due to the inherent nature of the Q-Learning algorithm. Implementing the proposed method in the numerical study section led to a 24. 8% electricity bill reduction. The numerical results prove the effectiveness of the proposed approach.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Issue Info: 
  • Year: 

    2012
  • Volume: 

    10
  • Issue: 

    1
  • Pages: 

    55-62
Measures: 
  • Citations: 

    0
  • Views: 

    1254
  • Downloads: 

    0
Abstract: 

Extracting bottlenecks improves considerably the speed of learning and the ability knowledge transferring in reinforcement learning. But, extracting bottlenecks is a challenge in reinforcement learning and it typically requires prior knowledge and designer’s help. This paper will propose a new method that extracts bottlenecks for reinforcement learning agent automatically. We have inspired of biological systems, behavioral analysts and routing animals and the agent works on the basis of its interacting to environment. The agent finds landmarks based in clustering and hierarchical object recognition. If these landmarks in actions space are close to each other, bottlenecks are extracted using the states between them. The Experimental results show a considerable improvement in the process of learning in comparison to some key methods in the literature.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Author(s): 

nikfarjam kazem

Journal: 

Issue Info: 
  • Year: 

    2023
  • Volume: 

    4
  • Issue: 

    8
  • Pages: 

    8-23
Measures: 
  • Citations: 

    0
  • Views: 

    120
  • Downloads: 

    22
Abstract: 

A self-adaptive system can modify its own structure and behavior at runtime based on its perception of the environment, of itself and of its requirements. One key element of a self-adaptive system is its self-adaptation logic that encodes when and how the system should adapt itself. When developing the adaptation logic, developers face the challenge of design time uncertainty. To define when the system should adapt, they have to anticipate all potential environment states. However, anticipating all potential environment changes is infeasible in most cases due to incomplete information at design time. Online reinforcement learning (RL) addresses design time uncertainty by learning the effectiveness of adaptation actions through interactions with the system’s environment at run time, thereby automating the development of self-adaptation logic. Online-RL for self-adaptive systems integrates the elements of RL into the MAPE-K loop Existing online RL approaches for self-adaptive systems represent learned knowledge as a value function, so exhibit two shortcomings that limit the degree of automation: they require manually fine-tuning the exploration rate and may require manually quantizing environment states to foster scalability. In this paper, use policy-based deep reinforcement learning, which are structurally quite different, to automate the aforementioned manual activities. Deep RL addresses these disadvantages by representing the learned knowledge as a neural network. learned knowledge is hidden in the neural network. The results of the experiments indicate a high convergence speed of learning.

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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