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Motivated by numerous applications in Monte Carlo techniques and as of late, in deriving non dominated solutions in multi-objective optimization problems, this article addresses generating uniform random variables (λi, λi ≥ 0, i = 1,..., n) over a simplex in ℝ2 (n ≥ 2), i.e., Σi=1 n λi = 1. In this article, first, conditional distribution of λi where Σi=1 n λi = 1 is derived and then inverse method is applied to generate random variables  

A growing number of distributed energy resources (DERs) connected to the distribution network presents operational challenges. Therefore, it is crucial to develop an effective framework to address these challenges. In this paper, a novel transactive energy market (TEM) framework is proposed in two levels based on the concept of a network usage fee (NUF) to address technical issues. We perform the peer matching process using a primal-dual algorithm at a lower level. We consider distribution system operation (DSO) operations (e.g., Volt/VAR control and network reconfiguration) and NUF to maintain network constraints and to provide an optimal network topology to facilitate energy trading. The... 

This paper presents a flexibility-oriented generation expansion planning (GEP) model with the goal of increasing renewable energy penetration. The model incorporates GEP and unit commitment while considering improved reserve requirements. Utilizing GEP and unit commitment results in considering short-term operational constraints. Furthermore, given the increase in renewable portfolio standards (RPS) and the need for accurate reserve requirements determination, it is essential to consider improved reserve requirements in the proposed model. Moreover, this model utilizes a metric that measures power system flexibility deficiency and leads to flexible power system expansion by integrating it... 

Million miles of gravity-fed drinking water and sewage pipelines around the world, especially in rural and urban areas in mountain ranges, have introduced a new renewable energy sources (RES), i.e., in-pipe hydropower systems (IHS). Output power of this technology, similar to other types of RES, suffers from intermittency, while it is still more predictable in comparison to other technologies of RESs. Besides, energy storage systems (ESS) are introduced as a pivotal technology for dealing with the intermittent and non-dispatchable characteristics of IHS through spatio-temporal arbitrage. This paper aims to develop a stochastic mixed-integer linear programming (MILP) formulation that... 

Graphene quantum dots (GQDs) are one of the most uprising nanomaterials that have been used in biomedical applications because of their interesting luminescent properties. This work presents a facile way to attach the LCysteine onto the surface of GQDs, which enhances the applicability of the final molecules in biomedical applications. Furthermore, the luminescent properties of synthesized GQDs and GQDs-LCysteine have been investigated with different methods. The obtained GQDs-LCysteine show a red shift in PL results with an increase in LCysteine content compared to GQDs. According to the results, this platform has the potential to be used in many biological applications, such as bio-imaging... 

The increasing use of electrical energy in nowadays modern societies and industries has brought about a sharp need for more efficient means of electricity generation. It seems rather logical to increase the electricity production proportional to the increasing rate of the demand. Distributed Generation (DG) has been recently accepted to be one of the most efficient means of electricity generation, particularly near to the load centers. The DG has been also considered in the generation expansion planning of power systems. In this paper, three main factors associated with the DGs placement procedure is scrutinized through a multi-objective optimization approach. One of the main factors... 

Open access to transmission networks as well as designing an efficient cost allocation method are the key points that provide free competition for participants in power market. Restructuring in power systems has created new challenges which emphasize the development and fairness of economical criteria such as pricing of different services in market environment. Besides, the charge of network usage is a controversial subject, itself. To address this problem, many methods for transmission line cost allocation have been proposed. Amongst them, MW-Mile methods are based on the extent of use concept. Inability to take various fixed together with variable imposed costs into account can be... 

In market-based planning studies, the financial aspects of transmission grids have been posed as a major challenge since these are important keys to provide a non-discriminative and competitive environment for energy market participants. In this respect, this paper proposes a probabilistic multi-objective transmission expansion planning algorithm considering private investors' preferences, technical concerns, and random nature of power system uncertainties. The combination of Non-Dominated Sorting Genetic Algorithm II, as a widely-used robust multi-objective optimization technique, and point estimation method is employed to handle non-commensurable probabilistic objective functions. The IEEE... 

Deregulation in power systems creates new uncertainties and escalates the previous ones. The presence of these uncertainties causes the transmission network to remain a monopoly and the private investors not to be interested in investing in new transmission lines. This article presents a new merchant-based transmission network expansion planning algorithm from the viewpoint of private investors. The point estimation method is used to handle the uncertainties, and the genetic algorithm is used as the optimization tool. The proposed method provides insights for private investors to deal with the uncertainties and to find appropriate transmission projects in which to invest. Copyright  

With the increasing rate of population in big cities around the world, the tendency to build new buildings in the suburb of main cities or to build large apartments in the main cities has been highlighted. In this regard, building residential complexes has seen a dramatic increase in these areas as it makes it possible to build a large number of residential units within a reasonable space. Although these complexes have brought numerous benefits, they are some challenges regarding their construction processes. One main concern associated with these complexes is how to optimally install energy components such as transformers, combined heat and power (CHP) units, boilers etc., in the shared... 

Nowadays, the high penetration of renewable energy resources, with variable and unpredictable nature, poses major challenges to operation and planning studies of power systems. Employing energy storage systems (ESSs) has been introduced as an effective solution to alleviate these challenges. Several studies have been presented in the literature to provide a framework for expansion planning studies of ESSs. However, they usually have two main drawbacks: i) ignoring the positive effect of independent-locally operated ESSs on the bulk power system preferences, ii) inability to model the charge/discharge schedule of independent-locally operated ESSs based on their investors' acceptable risk... 

The problem of edge dislocation inside the wall of a multi-walled nanotube accounting for the surface effects is addressed. Within the framework of surface elasticity the stress field is obtained, using complex potentials. Furthermore, the stress field and image forces acting on the dislocation, with and without an account of the surface stress, are compared together and discussed  

Behavior of a screw dislocation inside a nanotube (NT) is considered in the context of surface elasticity. The elastic fields as well as the image force acting over the dislocation are derived and analyzed in detail. In contrast with the result of classical elasticity, the screw dislocation is shown to be repelled by free surfaces and occupy two stable equilibrium positions near them. The image force strongly depends on the NT's inner and outer radii as well as surface elastic characteristics  

Along with the increasing demand for electrical power, distributed generations (DGs) have so far found their pivotal roles in the restructured environment of power distribution systems. As an indispensable step toward a more reliable power system, the DGs optimal allocation strategy, deemed to be the most techno-economically efficient scheme, comes to the play and is profoundly taken under concentration in this study. This paper devises a comprehensive multi-objective (MO) optimization approach by which all the crucial and maybe contradictory aspects of great influence in the placement process can be accounted for. Total imposed costs, total network losses, customer outage costs as well as... 

This paper proposes a generalized analytical approach to evaluate the reliability of active distribution networks. The studies are implemented in the context of renewable-based energy hubs. The reliability of energy demands is determined as a function of reliability characteristics of energy hub input resources and converters as well as hub operating strategies. The framework proposed in this paper involves the main attributes of different distributed generation technologies as well as vehicle-to-grid (V2G)-capable vehicles in the reliability studies. Dealing with the uncertainty in energy services provided by the wind turbine output generation and V2G programs, efficient probabilistic... 

Energy developments plays a crucial role in the political power, economic growth, social development and environmental degradation of developing countries. Energy consumption in residential sector is an essential issue for providing a large variety of services that are necessary for social life tasks such as heating, cooling, and lighting. Therefore, there is a need for depiction of energy outlook and selection of appropriate strategies as the main pillars of economic and political stability in each society. The main objective of this research is to design and apply a methodology that helps decision makers for simulation, optimization and analysis of the residential sector energy system. The... 

Long-term distribution network planning (DNP) is considered as one of the most challenging issues for distribution network operators (DNOs). By increasing EVs in cities, it has appeared some new players such as electric vehicles (EVs) owners and electric vehicle parking lots (EVPLs) owners for DNP. In this article, we conduct a new study on the coupled dynamic expansion problem of EVPLs placement and distribution networks. To reach this goal, at first, EVs driving and charging/discharging behavior as some influential factors is modeled using an efficient probabilistic algorithm. An analytical model is then introduced to estimate the number of EVs in EVPLs at different times. To find out the... 

This paper proposes a new framework for home energy management (HEM) in the context of renewable-based residential energy hub using a probabilistic optimization approach. Different energy converters and storages, including combined heat and power, a plug-in hybrid electric vehicle, a heat storage unit, solar panels, and generic household appliances, are considered in the energy hub. The customer's energy cost is considered as the objective of the HEM optimization problem and different operational limits of the energy hub components are modeled as the constraints. The two-point estimate method is incorporated in this paper to model the uncertainty associated with output power of the rooftop... 

Atomic force microscopes (AFM) are widely used for feature detection and scanning surface topography of different materials. Contrast of topography images is significantly influenced by the sensitivity of AFM micro cantilever which means enhancement of sensitivity leads to increase of topography images resolution So, in the last years numerous scientists interested in studying the effects of different parameters such as geometric one on the sensitivity of AFM micro cantilevers. V-shape micro cantilever types of AFMs probe are widely used to scan various types of surfaces. In V-shape micro cantilevers, there are many geometric and design parameters which influence the flexural sensitivity of...