doi:10.30723/ijp.v11i20.380

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Publication Date

Mon Feb 25 2019

Journal Name

Iraqi Journal Of Physics

Volume

11

Issue Number

20

DOI

10.30723/ijp.v11i20.380

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The nuclear level density parameter

Exciton model

level density parameter

state density

Rasha S.

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The nuclear level density parameter in non Equi-Spacing Model (NON-ESM), Equi-Spacing Model (ESM) and the Backshifted Energy Dependent Fermi Gas model (BSEDFG) was determined for 106 nuclei; the results are tabulated and compared with the experimental works. It was found that there are no recognizable differences between our results and the experimental -values. The calculated level density parameters have been used in computing the state density as a function of the excitation energies for ⁵⁸Fe and ²⁴⁶Cm nuclei. The results are in a good agreement with the experimental results from earlier published work.

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Publication Date

Mon Apr 24 2017

Journal Name

Spe Kingdom Of Saudi Arabia Annual Technical Symposium And Exhibition

Optimization of Infill Drilling in Whicher Range Field in Australia

machine learning

reservoir simulation

asset and portfolio management

cumulative production

transient drainage area

production rate

reservoir model

infill well

tight gas reservoir

Modeling & Simulation

Omar

Aswin R.

Md Mofazzal

Akim H.

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Abstract<p>Now that most of the conventional reservoirs are being depleted at a rapid pace, the focus is on unconventional reservoirs like tight gas reservoirs. Due to the heterogeneous nature and low permeability of unconventional reservoirs, they require a huge number of wells to hit all the isolated hydrocarbon zones. Infill drilling is one of the most common and effective methods of increasing the recovery, by reducing the well spacing and increasing the sweep efficiency. However, the problem with drilling such a large number of wells is the determination of the optimum location for each well that ensures minimum interference between wells, and accelerates the recovery from the field. Detail</p> ... Show More

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(8)

Publication Date

Tue Oct 20 2020

Journal Name

Ibn Al-haitham Journal For Pure And Applied Sciences

Comparison Among Three Estimation Methods to Estimate Cascade Reliability Model (2+1) Based On Inverted Exponential Distribution

inverted exponential distribution

Maximum Likelihood method

Uniformly Minimum Variance Unbiased method

Single Stage Shrinkage Estimator

Mean Squared Error and Cascade Reliability Model (2 1)

Sairan

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In this paper, we are mainly concerned with estimating cascade reliability model (2+1) based on inverted exponential distribution and comparing among the estimation methods that are used . The maximum likelihood estimator and uniformly minimum variance unbiased estimators are used to get of the strengths and the stress ;k=1,2,3 respectively then, by using the unbiased estimators, we propose Preliminary test single stage shrinkage (PTSSS) estimator when a prior knowledge is available for the scale parameter as initial value due past experiences . The Mean Squared Error [MSE] for the proposed estimator is derived to compare among the methods. Numerical results about conduct of the considered

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Publication Date

Sun Sep 04 2011

Journal Name

Baghdad Science Journal

Pulse Profile Rule in Laser Heating of Opaque Targets in Air

A theoretical model is developed to determine time evolution of temperature at the surface of an opaque target placed in air for cases characterized by the formation of laser supported absorption waves (LSAW) plasmas. The model takes into account the power temporal variation throughout an incident laser pulse

(i.e. pulse shape

or simply: pulse profile). Three proposed profiles are employed and results are compared with the square pulse approximation of a constant power.

Bassam H.

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A theoretical model is developed to determine time evolution of temperature at the surface of an opaque target placed in air for cases characterized by the formation of laser supported absorption waves (LSAW) plasmas. The model takes into account the power temporal variation throughout an incident laser pulse, (i.e. pulse shape, or simply: pulse profile).
Three proposed profiles are employed and results are compared with the square pulse approximation of a constant power.

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Publication Date

Tue Oct 01 2013

Journal Name

Journal Of Economics And Administrative Sciences

أثـر الأدوات الداخلية لحوكمة الشركة على رأس المال الـعـامـل وانعكاسهما علـى القيـمـة الاقتصـادية المضـافـة: دراســة تطبيقيـة علـى عينــة مـــن الشـركــات الصنــاعــيــة المـدرجــة في بورصــة عـمّــان لــلأوراق المـالـيـة

/ Corporate Governance Instrument- Net Working Capital- Economic Value Added- Weighted Average Cost of Capital- Capital Asset Pricing Model

أدوات حوكمة الشركات- صافي راس المال العامل- القيمة الاقتصادية المضافة- المتوسط الموزون لكلفة راس المال- نموذج تسعير الاصول الرأسمالية.

ارشد فؤاد

احمد فارس

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Abstract

Objective of this research focused on testing the impact of internal corporate governance instruments in the management of working capital and the reflection of each of them on the Firm performance. For this purpose, four main hypotheses was formulated, the first, pointed out its results to a significant effect for each of corporate major shareholders ownership and Board of Directors size on the net working capital and their association with a positive relation. The second, explained a significant effect of net working capital on the economic value added, and their link inverse relationship, while the third, explored a significant effect for each of the corporate major shareholders ownershi

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Publication Date

Thu Mar 30 2023

Journal Name

Journal Of Economics And Administrative Sciences

Comparison of Some Methods for Estimating Nonparametric Binary Logistic Regression

Binary logistic regression model

Nadaraya–Watson method

Local Scoring algorithm

Cross validation method

generalized Cross validation

Plug in method.

انموذج الانحدار اللوجستي الثنائي

طريقه ناداريا –واتسون

خوارزمية التهديف الموضعي

طريقة العبور الشرعي

العبور الشرعي المعمم

طريقة الملئ المباشر .

Narjes

Lekaa

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In this research, the methods of Kernel estimator (nonparametric density estimator) were relied upon in estimating the two-response logistic regression, where the comparison was used between the method of Nadaraya-Watson and the method of Local Scoring algorithm, and optimal Smoothing parameter λ was estimated by the methods of Cross-validation and generalized Cross-validation, bandwidth optimal λ has a clear effect in the estimation process. It also has a key role in smoothing the curve as it approaches the real curve, and the goal of using the Kernel estimator is to modify the observations so that we can obtain estimators with characteristics close to the properties of real parameters, and based on medical data for patients with chro

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Publication Date

Sat Oct 01 2016

Journal Name

Journal Of Theoretical And Applied Information Technology

Factors affecting global virtual teams’ performance in software projects

Today the trend is to perform software development work via distributed geographical area among team

individual or even as an organization. However

due to the global market and international presence of many companies

there is a need to implement a global virtual teams. The global virtual team members are gradually engaged in globalized business environments across space

time and organizational boundaries via information and communication technologies. A global virtual team relies on communication

collaboration

and information exchange are the most important criteria in global virtual teams’ operations. The purpose of this paper is to answer two research questions. The first research question is to identify the factors affecting global virtual teams’ performance. A systematic literature review was conducted to answer the first research question. The second research question is on what the rank of the factor affecting the global virtual teams’ performance according to their level of effect on global virtual teams’ performance. Online survey was conducted within 103 developers and IT managers from eight IT companies to answer the second research question. The Statistical Package for Social Science (SPSS 22) was used to analyze the collected data. In this study

we investigated factors that affect global virtual teams’ performance

factors considered include cultural differences

language problems

time-zone differences

team size

technical problems

lack of trust

lack of sufficient training

and ICT problems. Also the findings indicated that lack of sufficient training is the highest level of effect on global virtual teams’ performance. On the other hand

Ali Yahya Gheni

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(23)

Publication Date

Mon Apr 06 2020

Journal Name

August

INFLUENCE OF SOME FACTOR ON SOMATIC EMBRYOS INDUCTION AND GERMINATION OF DATE PALM CV BARHI BY USING CELL SUSPENSION CULTURE TECHNIQUE

This study was done to examine different concentrations of mercuric chloride (Hgcl2) for Explants sterilization and different concentration of NAA) mg/L with 2iP for their effect on initiation primary callus and subsequent embryogenesis in Phoenix dactyliferae cultivar Barhi. Leaf primordial and shoot tips were excised from 2-3 years old offshoot. The result showed that contamination percentage decreased with an increase in concentration of Hgcl2 for two explants where in the control (0.0)% gave highest value 75% and 62.5% of contamination for leaf primordial and shoot tip respectively while the addition (0.1)% gave a significant decrease 37.5 and 0% for explants respectively. The Explants were inoculated onto Murashiege and Skoog

1962 (MS) medium supplemented with 2iP 3mg/L and containing 0

25

50 or 100 mg/L of NAA

the addition (50) mg/L of NAA gave highest value 68.8% in percentage of callus initiation with significant difference from addition 0% gave lowest value (18.8)%

as well Explants of shoot tip gave significant difference was 53.1% while leaf primordial gave 28.1%

Primary callus was transferred to fresh MS medium containing (0

5

10 and 20) mg/L of NAA with 3mg/L 2iP

Results were recorded after 12 weeks. A highest value of embryonic callus induction percentage or fresh weight and dry weight 87.5% or 1.56g and 0.47g for the character respectively for the treat 20 mg/L while control treatment 0.0 gave the lowest value 12.5% or 0.37g and 0.14g for same character respectively. Inoculated 1g fresh biomass into a 250 ml Erlenmeyer flask containing 50 ml MS liquid medium supplemented with NAA 20mg/L and agitated at 150 rpm by shaker to making suspension culture the measurements of packed cell volume ( pcv) or fresh and dry weight taken weekly for 12 weeks

maximum values were reached in the eighth week of PCV and fresh weight but the dry weight reached to highest value in seventh week

then the curve began to decline gradually until it reached stability in the last two weeks. The cell suspension was Diluted to different initial cell density of 100

500

10000

50000 and 100000 cells /ml with hemocytometer. The initial cell number of (10000) cells gave significant different of plating efficiency PE (11.6)% while (100) cells gave lowest value 1.8% of PE.

Ali A.

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Publication Date

Fri Mar 01 2019

Journal Name

Applied Acoustics

Theoretical model of absorption coefficient of an inhomogeneous MPP absorber with multi-cavity depths

Micro-perforated panel (MPP) absorber has been known as an alternative absorber to classical porous material given its facile installation

long durability

environmental friendliness and attractive appearance. Extensive studies of MPP absorber proposing the improvement of its absorption frequency bandwidth have been published. This study presents a MPP absorber introduced with inhomogeneous perforations and with multi-cavity depths. The MPP is divided into two sub-area

where each area has different hole diameter

perforation ratio and a separated backed cavity depth. The acoustic impedance is modelled using electrical equivalent circuit and the absorption coefficient is calculated under normal-incidence of sound. It is found that the inhomogeneous MPP can have good bandwidth of absorption by designing the sub-MPP of smaller perforation ratio with large hole diameter and the one having the larger perforation ratio with smaller hole diameter. The absorption bandwidth can be conveniently controlled by adjusting the cavity depth of each sub-MPP. The results from the experimental work show good agreement with the theoretical model.

Ali Ibrahim

Azma

Roszaidi

Iwan

Al-Ameri

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