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Performance Estimation of Heat Exchanger Operates By Evaporative Cooling Manner
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        In this study the design and installation of evaporative air cooler was carried out using completely outdoor air (fresh air) according to two stage evaporative cooling principle. The laboratory equipment was installed by designing and manufacturing a cross flow plate heat exchanger, where aluminum plates used for this purpose with dimensions (50 × 30 × 40 cm). The surfaces of heat exchanger were covered by sawdust from wetted channels side, to increase the percentage of wetting these surfaces and hence improve the performance and efficiency of air cooler.

        An experimental study was carried out to estimate the performance of cooling system, where some of the dominant effective parameters were studied like air flow rate and flow rate and effect the static pressure drop of air and the heat transfer of performance .Air flow rate was ranged between (142.90 to 1461.50 m3 / hr) and water flow rate was varied from (144 L / hr) to (1050 L / hr).

        The experimental results showed that the optimum flow rate of air prepared by the air cooler is (824.7 m3 / hr), As it to be seen from the study that treating the heat exchanger surfaces by sawdust improves the air cooler efficiency about (10 %), but in the other hand leads to increase the static pressure drop in proportion (21%) approximately, and hence increase consumed power about (9 %).The results also show the air cooler can not be used in regions that have moisture content accedes (11.90 g moisture/kg dry air).

 

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Publication Date
Tue Nov 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Performance evaluation of policies and programs accordance with guide prepared by a dutch court of audit and the board of supreme audit (case study in wasit state company for textile industries)
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Abstract\

preparation process of performance evaluation in organizations is of extreme importance, and under development in organizations and the opening of markets and technological developments in the industry and heightened competition among industrial organizations imposed systems are built for performance give a clear picture about performance and competition,  And centered research problem in answering the following questions: Is performance evaluation system is available in Wasit State Company for Textile Industries(Research sample ), This research aims to assess the performance of policies and programs in the company, according to guide performance evaluation of programs and policies prepared by the Dutch Cou

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Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Economics And Administrative Sciences
Estimating the Population Mean in Stratified Random Sampling Using Combined Regression with the Presence of Outliers
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In this research, the covariance estimates were used to estimate the population mean in the stratified random sampling and combined regression estimates. were compared by employing the robust variance-covariance matrices estimates with combined regression estimates by employing the traditional variance-covariance matrices estimates when estimating the regression parameter, through the two efficiency criteria (RE) and mean squared error (MSE). We found that robust estimates significantly improved the quality of combined regression estimates by reducing the effect of outliers using robust covariance and covariance matrices estimates (MCD, MVE) when estimating the regression parameter. In addition, the results of the simulation study proved

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Publication Date
Fri Jan 31 2025
Journal Name
Journal Of Al-qadisiyah For Computer Science And Mathematics
Modified LASS Method Suggestion as an additional Penalty on Principal Components Estimation – with Application-
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This research deals with a shrinking method concernes with the principal components similar to that one which used in the multiple regression “Least Absolute Shrinkage and Selection: LASS”. The goal here is to make an uncorrelated linear combinations from only a subset of explanatory variables that may have a multicollinearity problem instead taking the whole number say, (K) of them. This shrinkage will force some coefficients to equal zero, after making some restriction on them by some "tuning parameter" say, (t) which balances the bias and variance amount from side, and doesn't exceed the acceptable percent explained variance of these components. This had been shown by MSE criterion in the regression case and the percent explained v

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Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Use Generalized Pareto Survival Models to Estimation Optimal Survival Time for Myocardial Infarction Patients
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The survival analysis is one of the modern methods of analysis that is based on the fact that the dependent variable represents time until the event concerned in the study. There are many survival models that deal with the impact of explanatory factors on the likelihood of survival, including the models proposed by the world, David Cox, one of the most important and common models of survival, where it consists of two functions, one of which is a parametric function that does not depend on the survival time and the other a nonparametric function that depends on times of survival, which the Cox model is defined as a semi parametric model, The set of parametric models that depend on the time-to-event distribution parameters such as

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Publication Date
Tue Jan 01 2019
Journal Name
Baghdad Science Journal
Hazard Rate Estimation Using Varying Kernel Function for Censored Data Type I Article Sidebar
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n this research, several estimators concerning the estimation are introduced. These estimators are closely related to the hazard function by using one of the nonparametric methods namely the kernel function for censored data type with varying bandwidth and kernel boundary. Two types of bandwidth are used: local bandwidth and global bandwidth. Moreover, four types of boundary kernel are used namely: Rectangle, Epanechnikov, Biquadratic and Triquadratic and the proposed function was employed with all kernel functions. Two different simulation techniques are also used for two experiments to compare these estimators. In most of the cases, the results have proved that the local bandwidth is the best for all the types of the kernel boundary func

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Publication Date
Thu Nov 02 2017
Journal Name
Iraqi Journal Of Laser
Enhancement the Sensitivity of Humidity Sensor Based on an Agarose Coating Transmission-Type Photonic Crystal Fiber Interferometer
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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

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Publication Date
Sat Dec 31 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Performance Study of Electrodialysis for Treatment Fuel Washing Wastewater
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In this work, electrodialysis (ED) has been demonstrated to be appropriate technique for reducing the electrical conductivity of real wastewater from fuel washing unit, which has been previously treated by other electrochemical technology (electrocoagulation and electrooxidation).  A five cell electrodialysis stack, with an active membrane area of 60 cm2 per cell was employed. During a batch recirculation mode ED system, the effects of parameters such as electrical potential applied (6-18 V) and flow rate of streams (0.5-1.7 L/min.) on the performance of the total dissolved solids (TDS) separation and specific power consumption (SPC) were studied. The results indicate that the process of ED under potential (15 V) and flow

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Publication Date
Tue Jan 01 2019
Journal Name
Energy Procedia
Analysing of Hueckel Edge Detector Performance Using Satellite Image
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In this research, an analysis for the standard Hueckel edge detection algorithm behaviour by using three dimensional representations for the edge goodness criterion is presents after applying it on a real high texture satellite image, where the edge goodness criterion is analysis statistically. The Hueckel edge detection algorithm showed a forward exponential relationship between the execution time with the used disk radius. Hueckel restrictions that mentioned in his papers are adopted in this research. A discussion for the resultant edge shape and malformation is presented, since this is the first practical study of applying Hueckel edge detection algorithm on a real high texture image containing ramp edges (satellite image).

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Publication Date
Fri Jun 01 2018
Journal Name
International Journal Of Electrical And Computer Engineering (ijece)
Improvement of Fading Channel Modeling Performance for Wireless Channel
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Fading channel modeling is generally defined as the variation of the attenuation of a signal with various variables. Time, geographical position, and radio frequency which is included. Fading is often modeled as a random process. Thus, a fading channel is a communication channel that experiences fading. In this paper, the proposed system presents a new design and simulate a wireless channel using Rayleigh channels. Rayleigh channels using two approaches (flat and frequency-selective fading channels) in order to calculate some path space loss efforts and analysis the performance of different wireless fading channel modeling. The results show that the bite error rate (BER) performance is dramatically improved in the value of signal to

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Publication Date
Sat Oct 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
The role of performance management in Achieving Organizational success
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The idea of this research is the basis of the role exercised by the dimensions of performance management (Performance Planning- performance evaluation- improve the performance and development- feedback - Review and Performance Monitor) In order to achieve the success Organizational Is through the (strategic vision- the operational activity- development of the company- selection of personnel- the company's culture- Leadership and Management- Personal Development - Assessment and Review).And The research aims to identify the extent of the responsibility of performance management in achieving success  Organizational through main hypotheses branched out by the sub-hypotheses to knowing out the&nbs

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