An analytical method and a two-dimensional finite element model for treating the problem of laser heating and melting has been applied to aluminum 2519T87and stainless steel 304. The time needed to melt and vaporize and the effects of laser power density on the melt depth for two metals are also obtained. In addition, the depth profile and time evolution of the temperature before melting and after melting are given, in which a discontinuity in the temperature gradient is obviously observed due to the latent heat of fusion and the increment in thermal conductivity in solid phase. The analytical results that induced by laser irradiation is in good agreement with numerical results.
Photonic Crystal Fiber Interferometers (PCFIs) are widely used for sensing applications. This work presents the fabrication and the characterization of a relative humidity sensor based on a polymer-coated photonic crystal fiber that operates in a Mach- Zehnder Interferometer (MZI) transmission mode. The fabrication of the sensor involved splicing a short (1 cm) length of Photonic Crystal Fiber (PCF) between two single-mode fibers (SMF). It was then coated with a layer of agarose solution. Experimental results showed that a high humidity sensitivity of 29.37 pm/%RH was achieved within a measurement range of 27–95%RH. The sensor also showed good repeatability, small size, measurement accuracy and wide humidity range. The RH sensitivity o
... Show MoreMany of mechanical systems are exposed to undesired vibrations, so designing an active vibration control (AVC) system is important in engineering decisions to reduce this vibration. Smart structure technology is used for vibration reduction. Therefore, the cantilever beam is embedded by a piezoelectric (PZT) as an actuator. The optimal LQR controller is designed that reduce the vibration of the smart beam by using a PZT element.
In this study the main part is to change the length of the aluminum cantilever beam, so keep the control gains, the excitation, the actuation voltage, and mechanical properties of the aluminum beam for each length of the smart cantilever beam and observe the behavior and effec
... Show MoreThe main aim of this research paper is investigating the effectiveness and validity of Meso-Scale Approach (MSA) as a modern technique for the modeling of plain concrete beams. Simply supported plain concrete beam was subjected to two-point loading to detect the response in flexural. Experimentally, a concrete mix was designed and prepared to produce three similar standard concrete prisms for flexural testing. The coarse aggregate used in this mix was crushed aggregate. Numerical Finite Element Analysis (FEA) was conducted on the same concrete beam using the meso-scale modeling. The numerical model was constructed to be a bi-phasic material consisting of cement mortar and coarse aggregate. The interface between the two c
... Show MoreIn this paper, the Azzallini’s method used to find a weighted distribution derived from the standard Pareto distribution of type I (SPDTI) by inserting the shape parameter (θ) resulting from the above method to cover the period (0, 1] which was neglected by the standard distribution. Thus, the proposed distribution is a modification to the Pareto distribution of the first type, where the probability of the random variable lies within the period The properties of the modified weighted Pareto distribution of the type I (MWPDTI) as the probability density function ,cumulative distribution function, Reliability function , Moment and the hazard function are found. The behaviour of probability density function for MWPDTI distrib
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Irak’ın osmanlıcada yazılan sayısız elyazmalar çeşitli illerinde bulunur. Bunlardan Irak’ın başkenti olan Bağdat’tır. Irak Ulusal Müzesi Bağdad’ın uygarlık yerlerindendir. Elyazması Evi müzenin en önemli bölümleri sayılır. Orada osmanlıcada yazılan çok değerli elyazmalar bulunur. Bu elyazmalarından birisini ( fotokopi ) elde edip üzerinde çalışılmaktadır. Eser Antoloji şeklinde yazılmış. Bu eserden Sadullah Pâşâ’nın On Dokuzuncu Asır Manzumesini seçip ele alınmaktadır.
İki sayıfa ve 25 sat
... Show MoreThe First World War (1914-1918) was one of the most atrocious events in human history in which millions of people were killed and injured. Young men were widely recruited through a very strong persuasive propaganda, which portrayed the war as an opportunity for young men to defend their country and raise its banner high in the battlefields, prove their bravery and heroism, enjoy the adventure of action and taste the delight of battles. Military parades were usually held in the streets of towns where crowds, including young beautiful girls, stood along, hailing the new recruits who felt high pride in their uniform amidst the cheering applause of the happy audience. Newspapers and magazines used to publish so many stories of heroism about
... Show MoreThirteen morphometric characters of catfish
Two series of 1,3,4-oxadiazole derivatives at the sixth position of the 2,4-di-