A Strength Pareto Evolutionary Algorithm 2 (SPEA 2) approach for solving the multi-objective Environmental / Economic Power Dispatch (EEPD) problem is presented in this paper. In the past fuel cost consumption minimization was the aim (a single objective function) of economic power dispatch problem. Since the clean air act amendments have been applied to reduce SO2 and NOX emissions from power plants, the utilities change their strategies in order to reduce pollution and atmospheric emission as well, adding emission minimization as other objective function made economic power dispatch (EPD) a multi-objective problem having conflicting objectives. SPEA2 is the improved version of SPEA with better fitness assignment, density estimation, and modified archive truncation. In addition fuzzy set theory is employed to extract the best compromise solution. Several optimization run of the proposed method are carried out on 3-units system and 6-units standard IEEE 30-bus test system. The results demonstrate the capabilities of the proposed method to generate well-distributed Pareto-optimal non-dominated feasible solutions in single run. The comparison with other multi-objective methods demonstrates the superiority of the proposed method.
A metal mandrel was designed for manufacturing the cathodes of high power electron tube ( Tetrode ) used in broadcasting transmitting tubes type TH558 and CQS200.The cathodes were manufactured in the present work from thoriated tungsten wires ( 2? ThO2- W) with different diameters .These cathodes were carbonized in sequences of processes to determine the carbonization parameters (temperature, pressure, time, current and voltage).Then the carbonized cathodes dimension were accurately measured to determine the deviation due to the high temperature distortion effect at about 1800°C .the distorted cathodes due to the carbonization process was treated when it was subjected inside the vacuum chamber and heat treated again .The carbonized cat
... Show MoreThis research involves the preparation of new ligands 1,1,2,2- tetrakis (sodium acetate thio)ethylene(L1) and 1,1,2- tris(sodiumacetatethio) ethylene(L2), through the reaction of disodium thioglycolate) with tetra chloro ethylene or tri chloro ethylene in (1:4) or (1:3) moler ratio . Homodinucliar complexes of general formlu [M2(L1)] and [M2(L2)ClH2O] , when M= Co(II), Ni(II), Cu (II) and Zn(II) also mono nuclear complexes of general formula [M(L2)] . The prepared complexes were characterized using spectral method (UV/Visible/ IR) , metal content analysis , magnetic and atomic measurements . The spectral and magnetic measurement indicats that some complexes have tetrahedral or square planar complexes environtment .
An adaptive nonlinear neural controller to reduce the nonlinear flutter in 2-D wing is proposed in the paper. The nonlinearities in the system come from the quasi steady aerodynamic model and torsional spring in pitch direction. Time domain simulations are used to examine the dynamic aero elastic instabilities of the system (e.g. the onset of flutter and limit cycle oscillation, LCO). The structure of the controller consists of two models :the modified Elman neural network (MENN) and the feed forward multi-layer Perceptron (MLP). The MENN model is trained with off-line and on-line stages to guarantee that the outputs of the model accurately represent the plunge and pitch motion of the wing and this neural model acts as the identifier. Th
... Show MoreBackground: Diarrheal diseases are still a major public health problem especially in developing countries, due to their high morbidity & mortality rates, moreover the lagest
number of deaths with diarrheal diseases are due to persistent diarrheal states.We attemted to evaluate the size of the problem in our infants, and assess risk factors & outcome.
Methods: A retrospective study was performed in Al-Kadhemya teaching hospital, to evaluate diarrheal cases in under 2 years of age children , admitted to hospital during the period (Dec. 1991- Dec. 2001), from a total of 863, chronic diarrheal cases formed 286 (33.14%) that were evaluated for certain variables; epidemiology & risk factors etiology ,
The research problem is that the traditional methods of internal auditing are somewhat heavy with long and rigid procedures for the members of the audit process team, especially in light of the current developments that are reflected in the business environment and internal audit reports, so it is necessary to reconsider the traditional internal audit work method and assess the extent of its development by agile methods to reduce the time of the audit process on the activities and elements that add value and direct the effort and time to the activities and elements that add value to the work of the economic unit and the report of the internal auditor.
The research aims to study the possibility of applying agile internal auditing
... Show MoreQuantitative and qualitative composition of benthic invertebrate communities was studied during the period from January to December2012 at four stations that were selected on the Tigris River at Baghdad Province. One of the stations S2 located near Al-Rasheed Power Plant (RPP) to represent the ecological features of the plant site, whereas other stations, S1 were located at the upstream of the RPP as a control station to investigate the ecological characters of the Tigris River. Moreover, the two other stations S3 and S4 were located down to the impact of RPP to reflect the possible effects of the plant on the ecology of the river by comparison with the control stations. The present study recorded 44 taxa belong to 4 o
... Show MoreIn this paper, we derive and prove the stability bounds of the momentum coefficient µ and the learning rate ? of the back propagation updating rule in Artificial Neural Networks .The theoretical upper bound of learning rate ? is derived and its practical approximation is obtained
A piezoelectric cantilever beam with a tip mass at its free end is a common energy harvester configuration. This article introduces a new principle of designing such a harvester that increases the generated power without changing the resonance frequency of the harvester: the attraction force between two permanent magnets is used to add stiffness to the system. This magnetic stiffening counters the effect of the tip mass on the efficient operation frequency. Five set-ups incorporating piezoelectric bimorph cantilevers of the same type in different mechanical configurations are compared theoretically and experimentally to investigate the feasibility of this principle: theoretical and experimental results show that magnetically stiffened harve
... Show MoreChina occupies an area of 906 million square km. and lies east Asia. Its population approximately 1,388 people, according to census 2010. China was a global great power for centuries , then shrank its jurisdiction and occupied by European countries and Japan in the 19th century. It regained its strength and independence under the leadership and rule of the Chinese Communist Party since 1949. In the 21st century , the Chinese positions has risen universally due to its achievements in the economic and trade affairs . Nowadays, China became a largest exporting state in the world and a second economic power after USA.