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Reliability Evaluation of Renewable Energy Share in Power Systems  [PDF]
Zeyad A. Haidar, Abdullah M. Al-Shaalan
Journal of Power and Energy Engineering (JPEE) , 2018, DOI: 10.4236/jpee.2018.69006
Abstract: In this research, Renewable Energy (RE) represents the existing power systems with different levels. However, because of the intermittent nature of these sources, it is necessary to analyze systems’ reliability with different RE penetration levels. This work presented a simulation method for reliability evaluation of renewable penetrated power systems. Some reliability indices were proposed for the case of power systems with renewable power plants. The adopted approach used the historical data of renewable energy resources, mainly wind and solar to estimate the power that can be generated and compared with the demand to find the power mismatch. Therefore, this approach can be utilized to determine the penetration level that renewable energy can be shared, and it also helps the system operators in deciding the percentage of the generation that RE power plant can provide.
On the reliability of a renewable multiple cold standby system  [PDF]
E. J. Vanderperre
Mathematical Problems in Engineering , 2005, DOI: 10.1155/mpe.2005.269
Abstract: We present a general reliability analysis of a renewable multiple cold standby system attended by a single repairman. Our analysis is based on a refined methodology of queuing theory. The particular case of deterministic failures provides an explicit exact result for the survival function of the duplex system.
On the reliability of a renewable multiple cold standby system
Vanderperre E. J.
Mathematical Problems in Engineering , 2005,
Abstract: We present a general reliability analysis of a renewable multiple cold standby system attended by a single repairman. Our analysis is based on a refined methodology of queuing theory. The particular case of deterministic failures provides an explicit exact result for the survival function of the duplex system.
Optimal Power Allocation for Renewable Energy Source  [PDF]
Abhinav Sinha,Prasanna Chaporkar
Mathematics , 2011,
Abstract: Battery powered transmitters face energy constraint, replenishing their energy by a renewable energy source (like solar or wind power) can lead to longer lifetime. We consider here the problem of finding the optimal power allocation under random channel conditions for a wireless transmitter, such that rate of information transfer is maximized. Here a rechargeable battery, which is periodically charged by renewable source, is used to power the transmitter. All of above is formulated as a Markov Decision Process. Structural properties like the monotonicity of the optimal value and policy derived in this paper will be of vital importance in understanding the kind of algorithms and approximations needed in real-life scenarios. The effect of curse of dimensionality which is prevalent in Dynamic programming problems can thus be reduced. We show our results under the most general of assumptions.
Safety reliability optimal allocation of food cold chain  [PDF]
Yifeng Zou, Ruhe Xie, Guanghai Liu
Agricultural Sciences (AS) , 2013, DOI: 10.4236/as.2013.49B012
Abstract:

This paper applied the safety reliability of food cold chain logistics to establish reliability allocation model for cold chain systems, designed optimization algorithms, and made a case analysis. By applying system reliability allocation principle, this article firstly built safety reliability allocation model of food cold chain logistics system without cost constraint based on the safety reliability model of food cold chain logistics system, and then it set up optimal decision- making model of food cold chain logistics system with cost constraint using the functional relationship between the time, temperature of cold chain logistics and logistics costs. Next, according to the characteristics of the model, a heuristic algorithm was proposed to allocate safety reliability of the system to each cold chain unit so as to achieve the goal of operatingcosts optimization subject to assurance ofoverall safety reliability of the cold chain system. Taking the safety impact factor of food cold chain unit as a weight, the article also deduced the equation of reallocation of safety reliability of food cold chain system. In the end, these models were used to optimize the allocation of safety reliability in an example of Sushi cold chain process. It provided a new thought and method to optimally plan the unit safety of food cold chain system as well as reduce the cost of food cold chain.

Indices to Assess the Integration of Renewable Energy Resources on Transmission Systems  [PDF]
Alexandros I. Nikolaidis,Francisco M. Gonzalez-Longatt,C. A. Charalambous
Conference Papers in Science , 2013, DOI: 10.1155/2013/324562
Abstract: The continuous increase on the penetration levels of Renewable Energy Sources (RESs) in power systems has led to radical changes on the design, operation, and control of the electrical network. This paper investigates the influence of these changes on the operation of a transmission network by developing a set of indices, spanning from power losses to GHG emissions reduction. These indices are attempting to quantify any impacts therefore providing a tool for assessing the RES penetration in transmission networks, mainly for isolated systems. These individual indices are assigned an analogous weight and are mingled to provide a single multiobjective index that performs a final evaluation. These indices are used to evaluate the impact of the integration of RES into the classic WSCC 3-machine, 9-bus transmission network. 1. Introduction European Union countries have a set of specific targets to promote the use of energy from Renewable Energy Source (RES) in accordance with the Directive 2009/28/EC of the European Parliament [1]. These National Action Plans (NAPs) consider and set targets for the final use of energy for heating and cooling, electricity generation, and transportation. In particular, electricity generation is of great interest as it requires the liberalization of the electricity markets. The 16% of global final energy consumption comes from renewable sources during 2012, with 10% coming from traditional biomass, which is mainly used for heating and 3.4% from hydroelectricity. New renewable sources (small hydro, modern biomass, wind, solar, geothermal, and biofuels) accounted for another 2.8% and are growing very rapidly [2]. The share of renewable sources in electricity generation is around 19%, with 16% of global electricity coming from hydroelectricity and 3% from new renewable sources [2]. Nevertheless, RESs have not been a significant part of the energy mix for the vast majority of countries around the world, fact which has led governments to provide incentives to entities that are interested in investing in RES electricity generation, in most cases using wind and solar power. Consequently, it is of crucial importance to investigate how RES generation affects the network’s operational ability and which potential configurations could prove beneficial. Hence, a series of technical aspects must be considered by the planners in order to evaluate the pros and cons of such penetration. In particular, the minimization of power losses has so far been the most important issue for the planners [3, 4]. However, other grid related technical aspects
Media content allocation based on insisting indices
M.Krishnamoorthy, 2 P.Deepa, 3 R.Rajasekar
International Journal of Computer Trends and Technology , 2011,
Abstract: Media content allocation using insist indices is to attain a given average delay target with lowest possible utilization of the central server by using the hybrid scheme. The analysis is carried out in an order scaling depending on the total potential mass of customers in the market. The study explains the relative performance of peer-to-peer and centralized client–server schemes, as well as a hybrid of the two: both from the point of view of consumers as well as the media content allocation. The allocation is totally based on the insisting indices. The necessary insists can be used to take provisioning decisions. It can be exceptionally responsive to bursty insist by increasing their service capacity exponentially, while exhibiting nice performance scaling to the offered loads during stationary regimes
Assessment of Operating Condition Dependent Reliability Indices in Microgrids  [PDF]
Rafael Medeiros, Xufeng Xu, Elham Makram
Journal of Power and Energy Engineering (JPEE) , 2016, DOI: 10.4236/jpee.2016.44006
Abstract: Reliability results are important for proper planning and operation of utility companies. At the base of this method of analysis is the failure rate of the system components. In the traditional method, this probability of failure is determined by the components’ manufacturer and is considered to be constant. This study proposes a dynamic modeling of failure rate, taking the system operating conditions into consideration. With this new consideration, an IEEE test system has seven of its reliability indices quantified for comparison. The inclusion of the newly modeled failure rate leads to a worsening of 11.07% in the indices, on average. A second analysis is performed considering the presence of DG sources within the microgrid, namely PV and wind based. An improvement of 0.71% on the indices is noticed, once the DG sources are introduced. Finally, the effects of storage systems in the microgrid are investigated through a third scenario, in which two 2 MWh battery systems are introduced, and an improvement of 3.05% is noticed in the reliability indices.
An Innovative Approach for Improving the Reliability of Reticulated Porous Ceramics
An Innovative Approach fro Improving the Reliability of Reticulated Porous Cermaics

Xinwen ZHU,Dongliang JIANG,Shouhong TAN,
XinwenZHU
,DongliangJIANG

材料科学技术学报 , 2002,
Abstract: An innovative approach has been developed to fabricate reticulated porous ceramics (RPCs) with uniform macrostructure by using the polymeric sponge as the templates. In this approach, the coating process comprises of two stages. In the first stage, the thicker slurry was used to coat uniformly the sponge substrate. The green body was preheated to produce a reticulated perform with enough handling strength after the sponge was burned out. In the second stage, the thinner slurry was used to coat uniformly the preform. The population of the microscopic and macroscopic flaws in the structure is reduced significantly by recoating process. A few filled cells and cell faces occur in the fabrication and the struts were thickened. A statistical evaluation by means of Weibull statistics was carried out on the bend strength data of RPCs, which were prepared by the traditional approach and innovative approach, respectively. The result shows that the mechanical reliability of RPCs is improved by the innovative approach. This innovative approach is very simple and controlled easily, and will open up new technological applications for RPCs.
Decentralized Energy Allocation for Wireless Networks with Renewable Energy Powered Base Stations  [PDF]
Dapeng Li,Walid Saad,Ismail Guvenc,Abolfazl Mehbodniya,Fumiyuki Adachi
Computer Science , 2015,
Abstract: In this paper, a green wireless communication system in which base stations are powered by renewable energy sources is considered. This system consists of a capacity-constrained renewable power supplier (RPS) and a base station (BS) that faces a predictable random connection demand from mobile user equipments (UEs). In this model, the BS powered via a combination of a renewable power source and the conventional electric grid, seeks to specify the renewable power inventory policy, i.e., the power storage level. On the other hand, the RPS must strategically choose the energy amount that is supplied to the BS. An M/M/1 make-to-stock queuing model is proposed to investigate the decentralized decisions when the two parties optimize their individual costs in a noncooperative manner. The problem is formulated as a noncooperative game whose Nash equilibrium (NE) strategies are characterized in order to identify the causes of inefficiency in the decentralized operation. A set of simple linear contracts are introduced to coordinate the system so as to achieve an optimal system performance. The proposed approach is then extended to a setting with one monopolistic RPS and N BSs that are privately informed of their optimal energy inventory levels. In this scenario, we show that the widely-used proportional allocation mechanism is no longer socially optimal. In order to make the BSs truthfully report their energy demand, an incentive compatible (IC) mechanism is proposed for our model.
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