The present work includes a design and characteristics study of a controlling the wavelength of high power diode laser by thermoelectric cooler [TEC] . The work includes the operation of the [TEC] to control the temperature of the diode laser between ( 0- +30) °C by changing the resistance of thermistor. We can control a limited temperature of a diode laser by changing the phase cooling between hot and cold faces of the diode, this process can be attempted by comparator type [LM –311] .The theoretical results give a model for controlling the temperature with, the suitable wavelength.
thirty adult NewZealand rabbits used in this study, they were divided in to two groups (control and treaded with Helium — Neon laser). A square skin flap done on the medial aspect of the auricle of both sides, a square piece of cartilage incised, pealed out from each auricle and fixed in the site of the other, then the flaps sutured .The site of the operation in the rabbits of the treated group were irradiated using a Helium —Neon laser with (5mw) power for (10 days) began after the operation directly, (3 rabbits) from each group used for collection of specimens for histopathological examination at the weeks (1,2,3,4, & 6) weeks post the operation .The results revealed Early invasion of the matrix with elastic fibers which continue to t
... Show MoreThe current standard for treating pilonidal sinus (PNS) is surgical intervention with excision of the sinus. Recurrence of PNS can be controlled with good hygiene and regular shaving of the natal cleft, laser treatment is a useful adjunct to prevent recurrence. Carbon dioxide (CO2) laser is a gold standard of soft tissue surgical laser due to its wavelength (10600 nm) thin depth (0.03mm) and collateral thermal zone (150mic).It effectively seals blood vessels, lymphatic, and nerve endings, Moreover wound is rendered sterile by effect of laser. Aim of this study was to apply and assess the clinical usefulness of CO2 10600nm laser in pilonidal sinus excision and decrease chance of recurrence. Design: For 10 patients, between 18 and 39 year
... Show MoreThis research investigated the effectiveness of using different thickness values of polyimide (PI) interfacial layer in order to improve electrical and thermal properties of Al/ PI /c-Si capacitor. The PI spectra produced by poly(amic acid) (PAA) were characterized by using FT-IR analysis. After imidization of PAA, some absorption peaks vanished, whereas PI peaks appeared, due to the complete conversion of PAA to PI.
The results show that thermal decomposition resistance of polyimide films increases with the increase of polyimide thickness, because of the increase of the imide bond and the decrease of the average distance between amide groups.
In this work, we studied the effect of power variation on inductively coupled plasma parameters using numerical simulation. Different values were used for input power (750 W-1500 W), gas temperature 300K, gas pressure (0.02torr), 5 tourns of the copper coil and the plasma was produced at radio frequency (RF) 13.56 MHZ on the coil above the quartz chamber. For the previous purpose, a computer simulation in two dimensions axisymmetric, based on finite element method, was implemented for argon plasma. Based on the results we were able to obtain plasma with a higher density, which was represented by obtaining the plasma parameters (electron density, electric potential, total power, number density of argon ions, el
... Show MoreIn this paper, the 5 minutes measured wind speed data for year 2012 at 10 meter height for Tweitha have been statically analyzed to assess the time of wind turbine electrical power generation. After collection Tweitha wind data and calculation of mean wind speed the cumulative Weibull diagram and probability density function was ploted, then each of cumulative Weibull distribution, cut-in and furling turbine wind speed could be used as a mathematical input parameters in order to estimate the hours of electrical power generation for wind turbine during one day or one year. In Tweitha site, found that the average wind speed was (v= 1.76 m/s), so five different wind turbines were be selected to calculate hours of electrical generation for A
... Show MoreOne of the serious problems in any wireless communication system using multi carrier modulation technique like Orthogonal Frequency Division Multiplexing (OFDM) is its Peak to Average Power Ratio (PAPR).It limits the transmission power due to the limitation of dynamic range of Analog to Digital Converter and Digital to Analog Converter (ADC/DAC) and power amplifiers at the transmitter, which in turn sets the limit over maximum achievable rate.
This issue is especially important for mobile terminals to sustain longer battery life time. Therefore reducing PAPR can be regarded as an important issue to realize efficient and affordable mobile communication services.
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تتحقق اهداف الدول عبر توظيف امكانياتها ومواردها ، وهذا التوظيف يقترن بوسائل مختلفة باختلاف الامكانيات المتاحة. وتتفاوت هذه الوسائل ما بين الاكراه والترغيب ، واحياناً من الممكن استخدام كلا الوسيلتين ، وتندرج هذه الوسائل من حيث تصنيفها ضمن نوعين رئيسين هما: القوة الصلبة ]القوة العسكرية والاقتصادية[ والقوة الناعمة ]استخدام جميع ادوات الترغيب وتسخيرها من اجل ان تُعجب بها الدول الاخرى وتنصاع
... Show MoreLaser scanning has become a popular technique for the acquisition of digital models in the field of cultural heritage conservation and restoration nowadays. Many archaeological sites were lost, damaged, or faded, rather than being passed on to future generations due to many natural or human risks. It is still a challenge to accurately produce the digital and physical model of the missing regions or parts of our cultural heritage objects and restore damaged artefacts. The typical manual restoration can become a tedious and error-prone process; also can cause secondary damage to the relics. Therefore, in this paper, the automatic digital application process of 3D laser modelling of arte
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, an
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Black paint laser peening (bPLP) technique is currently applied for many engineering materials , especially for aluminum alloys due to high improvement in fatigue life and strength . Constant and variable bending fatigue tests have been performed at RT and stress ratio R= -1 . The results of the present work observed that the significance of the surface work hardening which generated high negative residual stresses in bPLP specimens .The fatigue life improvement factor (FLIF) for bPLP constant fatigue behavior was from 2.543 to 3.3 compared to untreated fatigue and the increase in fatigue strength at 107 cycle was 21% . The bPLP cumulative fatigue life behav
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