@article { author = {}, title = {Synthesizing a specification-based monitor for safety requirements}, journal = {Iranian Journal of Science and Technology Transactions of Electrical Engineering}, volume = {34}, number = {3}, pages = {235-256}, year = {2010}, publisher = {Shiraz University}, issn = {2228-6179}, eissn = {}, doi = {10.22099/ijste.2010.821}, abstract = {Safety-critical systems such as medical and avionic ones are the systems in which failure to satisfy the user requirements may put man’s life and resources in jeopardy. Since the adequate reliability of the software of such systems may be unobtainable via formal methods and the software testing approach single-handedly, verification of run-time behavior of software against user requirements violation is considered as a complementary approach. However, the synthesis of such a run-time verifier, hereafter we have called it a monitor, is confronted with the challenging problem of verifying low-level run-time behavior of target software against high-level user requirements violation. To solve this problem, we propose an approach in two phases. In the first phase, we obtain­ user requirements and then specify their violation formally. This formal specification is a high-level version of user requirements violations and should be mapped to a low-level one. To this end, in the second phase we extract a tabular automaton from the formal specification of user requirements violations in order to determine a state-based specification of the violations. This low-level specification, which constitutes the core of the monitor, determines those states which target software should not reach. To show the effectiveness of our approach, we apply it to the synthesis of a monitor for verifying behavior of the Continuous Insulin Infusion Pump(CIIP) system.          }, keywords = {Safety-critical systems,run-time verification,event-based specification,state-based specification}, url = {https://ijste.shirazu.ac.ir/article_821.html}, eprint = {https://ijste.shirazu.ac.ir/article_821_52b1ba4f0a1454f546f7734935a60734.pdf} } @article { author = {}, title = {Modulation classification for burst-mode QAM signals in multipath fading channels}, journal = {Iranian Journal of Science and Technology Transactions of Electrical Engineering}, volume = {34}, number = {3}, pages = {257-274}, year = {2010}, publisher = {Shiraz University}, issn = {2228-6179}, eissn = {}, doi = {10.22099/ijste.2010.822}, abstract = {We present a new and efficient method for identifying the modulation type of a bursty QAM signal in the presence of additive white Gaussian noise (AWGN) in unknown fading channels and with unknown carrier phase. Our approach is based on an iterative combination of blind equalization and soft-clusteringtechniques, utilizes the constant modulus algorithm (CMA) for an initial reconstruction of the received signal constellation, and employs a nonparametric soft clustering method to identify a small set of possible modulations based on the partition coefficient (PC) criterion. We then use an iterative approach in utilizing the decision adjusted modulus algorithm (DAMA) to refine our choices until we reach two hypotheses. Besides, we propose a parallel implementation of the proposed method, and provide an asymptotic analysis as well as simulation results to demonstrate the validity and usefulness of the proposed method. Simulation results indicate that our proposed method achieves a significant gain as compared to the cumulant-based approach for burst mode transmissions in fading channels.          }, keywords = {Blind equalization,modulation classification,multipath fading channel,soft clustering}, url = {https://ijste.shirazu.ac.ir/article_822.html}, eprint = {https://ijste.shirazu.ac.ir/article_822_0ec768fd2b6e70517168b450fd920610.pdf} } @article { author = {}, title = {A multistage model for distribution expansion planning with distributed generation in a deregulated electricity market}, journal = {Iranian Journal of Science and Technology Transactions of Electrical Engineering}, volume = {34}, number = {3}, pages = {275-287}, year = {2010}, publisher = {Shiraz University}, issn = {2228-6179}, eissn = {}, doi = {10.22099/ijste.2010.823}, abstract = {Distribution systems management is becoming an increasingly complicated issue due to the introduction of new technologies, new energy trading strategies and a new deregulated environment. In the new deregulated energy market and considering the incentives coming from the technical and economic fields, it is reasonable to consider Distributed Generation (DG) as a viable option for systems reinforcement in competition with voltage regulator devices, to solve the lacking electric power supply problem and meet the load growth requirements with a reasonable price as well as the system power quality problems. The problem of optimal placement and size is formulated in two stages; minimization of the total costs to find optimal sizing and mounting of DG with different payback time, and maximization of the social welfare to find optimal payback time. In this framework, the object function is investment costs, which are evaluated as the annualized total investment cost, plus total running cost as well as cost of Energy Not Supply (ENS) and losses. Different system conditions are assumed to indicate the effect of the system conditions on planning decision as well as the effect of DG placement on improvement of system conditions. An optimal placement, size and investment payback time is identified. The proposed two-stage model aspects of system operation and economic aspects of market operation act as good indicators for the placement of Microturbine as a common type of DG, especially in a market environment. A software package is developed for this reason, which runs each type of planning problem very fast. The proposed methodology is tested in the IEEE 30-bus test system.           }, keywords = {distributed generation (DG),distribution company (DISCO),GAMS-MATLAB interface,investment payback time,microturbine,Social Welfare}, url = {https://ijste.shirazu.ac.ir/article_823.html}, eprint = {https://ijste.shirazu.ac.ir/article_823_ad2d5a89b33ca009d4b898135f102278.pdf} } @article { author = {}, title = {Computation of the split factor of earth fault currents by considering the proximity effects}, journal = {Iranian Journal of Science and Technology Transactions of Electrical Engineering}, volume = {34}, number = {3}, pages = {289-305}, year = {2010}, publisher = {Shiraz University}, issn = {2228-6179}, eissn = {}, doi = {10.22099/ijste.2010.824}, abstract = {To determine a safe substation grounding grid in power systems, it is important to compute the split factor for earth fault current including the proximity influences among the grid and the earthing systems of the incoming/outgoing transmission lines' towers. In this paper, a novel, simple and accurate method is developed for computing this factor that can correctly take into account the proximity effects. The results are compared with those that have been published (for the cases that they are able to compute) which show good agreement and accuracy.           }, keywords = {Split factor,proximity effects,earth fault currents,touch and step voltages,grounding grid design}, url = {https://ijste.shirazu.ac.ir/article_824.html}, eprint = {} } @article { author = {}, title = {Multi-objective planning model for integration of distributed generations in deregulated power systems}, journal = {Iranian Journal of Science and Technology Transactions of Electrical Engineering}, volume = {34}, number = {3}, pages = {307-324}, year = {2010}, publisher = {Shiraz University}, issn = {2228-6179}, eissn = {}, doi = {10.22099/ijste.2010.825}, abstract = {This paper presents a long-term dynamic multi-objective model for distributed generation investment. The proposed model optimizes three objectives, namely active losses, costs and environmental emissions and determines the optimal schemes of sizing, sitting of DG units and specially the dynamics of investment over the planning period. The Pareto optimal solutions of the problem are found using a GA algorithm and finally a fuzzy satisfying method is applied to select the optimal solution considering the desires of the planner. The solutions of Pareto optimal front are analyzed to extract general useful information for planners about the appropriate DG technologies and placement schemes. The effectiveness of the proposed model is demonstrated by applying it on a test distribution system and the results are presented, discussed and compared to other methods.           }, keywords = {Distributed generation,Genetic Algorithm,dynamic planning,Multi-objective optimization,active loss reduction}, url = {https://ijste.shirazu.ac.ir/article_825.html}, eprint = {https://ijste.shirazu.ac.ir/article_825_a5866bb9f77adbabcc4c8b920dc647eb.pdf} } @article { author = {}, title = {Generation expansion planning for Iran power grid}, journal = {Iranian Journal of Science and Technology Transactions of Electrical Engineering}, volume = {34}, number = {3}, pages = {325-333}, year = {2010}, publisher = {Shiraz University}, issn = {2228-6179}, eissn = {}, doi = {10.22099/ijste.2010.826}, abstract = {Generation expansion planning is one of the major modules of power system planning studies, normally performed for the next 10-30 years. Optimal generation expansion planning is a non-linear and limited optimization problem. All solutions are compared to each other in order to reach final optimal solution. Some simplifications are made to reduce the problem dimensions which will not lead to unreal results. In this paper, WASP software package, one of the well known power expansion planning softwares, is used to optimizeIrangeneration expansion planning. For modeling the power system, WASP uses the probabilistic simulation, while for optimization the dynamic programming method is used. In this paper, the generation system expansion planning is performed from 2009 till 2024 (a duration of 16 years). Finally, the sensitivity analysis is performed on the capital cost and the fuel cost of power plants.           }, keywords = {Optimal generation expansion planning,WASP software package,Sensitivity analysis}, url = {https://ijste.shirazu.ac.ir/article_826.html}, eprint = {https://ijste.shirazu.ac.ir/article_826_a78da5685241e133233f421f65d48135.pdf} }