Preferred Language
Articles
/
ijs-2003
Effect of Surface Recombination on Diffusion Length and Active Cavity Life time

This work presents an analytical study for simulating a Fabry-Perot Bi-stable etalon (F-P cavity) filled with a dispersive optimized nonlinear optical material (Kerr type) such as semiconductors Indium Antimonite (InSb). Depending on the obtained results and because of a trade-off between the optical path length of the sample and active cavity lifetime, an optimization procedure was applied on the InSb etalon/CO laser parameters; critical switching irradiance (Ic) was applied via simulation systems  of optimization procedures of optical cavity (Matlap program was used to study the optical Bi-stability of a nonlinear Fabry-Perot cavity). In order to achieve minimum switching power and faster switching time, the optimization surface recombination on the diffusion length and effective cavity lifetime was studied.

In addition, for a specific absorption value 400 cm-1, the lifetime coefficient  values were 0.33 , 0.091 , 0.0172 ns for sample thickness (D) = 500 , 60 , 20 mm, respectively. Also, for a bulk recombination time (Tl) of 200 ns, specific absorption (α) of 50 cm1, and D of 20 mm, the surface recombination speed value was  2.845 x 105 cm/sec, whereas the active lifetime, which is defined as the thickness over the surface recombination speed (sÏ…) (D/2sÏ…), was equal to 3.5ns.

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Jun 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Design Sampling Plan when Life Time Follows Logistic Distribution

Design sampling plan was and still one of most importance subjects because it give lowest cost  comparing with others, time live statistical distribution should be known to give best estimators for  parameters of sampling plan and get best sampling plan.

Research dell with design sampling plan when live time distribution follow Logistic distribution with () as location and shape parameters, using these information can help us getting (number of groups, sample size) associated with reject or accept the Lot

Experimental results for simulated data shows the least number of groups and sample size needs to reject or accept the Lot with certain probability of

... Show More
Crossref
View Publication Preview PDF
Publication Date
Thu Jun 08 2023
Journal Name
Iraqi Journal Of Laser
PDF The effect of nanoelectrodes number and length on enhancing the THz photomixer performance

Abstract: Despite the distinct features of the continuous wave (CW) Terahertz (THz) emitter using photomixing technique, it suffers from the relatively low radiation output power. Therefore, one of effective ways to improve the photomixer emitter performance was using nanodimensions electrodes inside the optical active region of the device. Due to the nanodimension sizes and good electrical conductivity of silver nanowires (Ag-NWs), they have been exploited as THz emitter electrodes. The excited surface plasmon polariton waves (SPPs) on the surface of nanowire enhances the incident excitation signal. Therefore, the photomixer based Ag-NW compared to conventional one significantly exhibits higher THz output signal. In thi

... Show More
View Publication Preview PDF
Publication Date
Wed Apr 01 2015
Journal Name
Mathematical Methods In The Applied Sciences
Scopus (28)
Crossref (21)
Scopus Clarivate Crossref
View Publication
Publication Date
Thu Mar 21 2024
Journal Name
International Development Planning Review
Publication Date
Sun Jul 04 2010
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Effect of active smoking on the tympanometry findings in adult men.

Background: Tympanometry findings are considered by many investigators to be associated with passive and active smoking.
Patients and methods: One hundred forty healthy adult men aged (20-50 years). 70 smokers and 70 nonsmokers were recruited for the study. The examination included otoscopy, and screening tympanometry. Smoking history was ascertained by self –report. For each subject, age, smoking status and number of cigarettes per day were noted.
Results: There is a tendency for more negative middle ear pressure in smokers than in non-smokers though this difference may not clinically significant. There were no significant differences in ear canal volume, middle ear compliance and presence of Staped

... Show More
Crossref
View Publication Preview PDF
Publication Date
Thu Jan 01 2015
Journal Name
Journal Of Engineering
Experimental Study of the effect of closed cavity wall on buildings cooling loads saving

The experimental study showed the use of closed cavity wall (the thickness of the cavity 5cm) made a percentage reduction in the cooling load caused by heat gain from the wall by (21.5 %) compared with the conventional wall. also the thermal resistance of the closed cavity was an average (0.2 m2.oC/W).

The experimental results of the study showed that the use of closed cavity wall reduced the average temperature of the inner surface of the wall during the day, and that the reduction was an average (0.45 oC)  when compared with the conventional wall , as well as the use of closed cavity wall reduced the temperature difference range of the inner surface of the wall during the day, and that the

... Show More
View Publication
Publication Date
Fri Jan 01 2016
Journal Name
Applied And Computational Mathematics
Crossref (2)
Crossref
View Publication
Publication Date
Fri Mar 29 2024
Journal Name
Iraqi Journal Of Science
Determination of Timewise-Source Coefficient in Time-Fractional Reaction-Diffusion Equation from First Order Heat Moment

     This article aims to determine the time-dependent heat coefficient together with the temperature solution for a type of semi-linear time-fractional inverse source problem by applying a method based on the finite difference scheme and Tikhonov regularization. An unconditionally stable implicit finite difference scheme is used as a direct (forward) solver. While by the MATLAB routine lsqnonlin from the optimization toolbox, the inverse problem is reformulated as nonlinear least square minimization and solved efficiently. Since the problem is generally incorrect or ill-posed that means any error inclusion in the input data will produce a large error in the output data. Therefore, the Tikhonov regularization technique is applie

... Show More
Scopus Crossref
Preview PDF
Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Study affects Pulse Parameters versus cavity length for both Dispersion Regimes in FM mode locked.: Bushra.R.Mhdi|Gaillan H.Abdullah|Mohand M.Azzawi|Nahla.A.Hessin|Basher.R.Mhdi

To demonstrate the effect of changing cavity length for FM mode locked on pulse parameters and make comparison for both dispersion regime , a plot for each pulse parameter as Lr function are presented for normal and anomalous dispersion regimes . The analysis is based on the theoretical study and the results of numerical simulation using MATLAB. The effect of both normal and anomalous dispersion regimes on output pulses is investigate Fiber length effects on pulse parameters are investigated by driving the modulator into different values. A numerical solution for model equations using fourth-fifth order, Runge-Kutta method is performed through MATLAB 7.0 program. Fiber length effect on pulse parameters is investigated by driving th

... Show More
Crossref
View Publication
Publication Date
Mon Jan 01 2018
Journal Name
Surface And Coatings Technology
Scopus (10)
Crossref (10)
Scopus Clarivate Crossref
View Publication