Estimating multivariate location and scatter with both affine equivariance and positive break down has always been difficult. Awell-known estimator which satisfies both properties is the Minimum volume Ellipsoid Estimator (MVE) Computing the exact (MVE) is often not feasible, so one usually resorts to an approximate Algorithm. In the regression setup, algorithm for positive-break down estimators like Least Median of squares typically recomputed the intercept at each step, to improve the result. This approach is called intercept adjustment. In this paper we show that a similar technique, called location adjustment, Can be applied to the (MVE). For this purpose we use the Minimum Volume Ball (MVB). In order to lower the (MVE) objective function. An exact algorithm for calculating the (MVB) is presented. As an alternative to (MVB) location adjustment we propose () location adjustment, which does not necessarily lower the (MVE) objective function but yields more efficient estimates for the location part. Simulations Compare the two type of location adjustment.
Electrical Discharge Machining (EDM) is a widespread Nontraditional Machining (NTM) processes for manufacturing of a complicated geometry or very hard metals parts that are difficult to machine by traditional machining operations. Electrical discharge machining is a material removal (MR) process characterized by using electrical discharge erosion. This paper discusses the optimal parameters of EDM on high-speed steel (HSS) AISI M2 as a workpiece using copper and brass as an electrode. The input parameters used for experimental work are current (10, 24 and 42 A), pulse on time (100, 150 and 200 µs), and pulse off time (4, 12 and 25 µs) that have effect on the material removal rate (MRR), electrode wear rate (EWR) and wear ratio (WR). A
... Show MoreIn this work the radioactive wastes in the Old Russian
Cemetery Al -Tuwaitha site were classified according to risks for
workers who are involved in the retrieval process. The exposure
assessment results expressed as estimates of radionuclide intakes by
inhalation and ingestion, exposure rates and duration for external
exposure pathways, and committed effective dose equivalents to
individuals from all relevant radionuclides and pathways. Results
showed the presence of natural radionuclides Ra-226, Th-234 and K-
40, as well as the produced radionuclide Cs-137 and Eu-152 in the
cemetery wells. The absorbed doses from the waste were classified to
two categories; exempt waste and low level waste according to
Foreign direct investment has seen increasing interest worldwide, especially in developing economies. However, statistics have shown that Yemen received fluctuating FDI inflows during the period under study. Against this background, this research seeks to determine the relationship and impact of interest rates on FDI flows. The study also found other determinants that greatly affected FDI inflows in Yemen for the period 1990-2018. Study data collected from the World Bank and International Monetary Fund databases. It also ensured that the time series were made balanced and interconnected, and then the Auto Regressive Distributed Lag method used in the analysis. The results showed that the interest rates and
... Show MoreThe aim of this work was to develop and validate a rapid and low cost method for estimation of ibuprofen in pharmaceutical suspensions using Reverse-Phase High Performance Liquid Chromatography. The proposed method was conducted and validated according to International Conference on Harmonization (ICH) requirements. The chromatographic parameters were as follows: column of octyldecylsilyl C18 with dimensions (150 × 4.6) mm, mobile phase composed of acetonitrile with phosphoric acid with a ratio of 50 to 50 each using isocratic mode, flow rate of 1.5 mL/min and injection volume of 5 μL. The detection was carried out using UV detector at 220 nm. The method was validated and showed short retention time for ibuprofen peak at 7.651 min, wit
... Show MoreThe research aims to shed light on the amount of proceeds annual tax for each of the way the contract total and percentage of completion method - see which is better - as well as the current problems arising from the application method of the contract in full in settling accounts tax - to identify problems - related to postpone settling accounts tax in accordance with the way the contract fully and determine the advantages and disadvantages of each of the methods through practical application , and then use the results as inputs to help in the decision to confirm the continuation of the GCT using a full decade in settling accounts tax for long-term construction contracts or forgo them.
Were the result of research the existence of
... Show MoreThe research involves preparing gold nanoparticles (AuNPs) and studying the factors that influence the shape, sizes and distribution ratio of the prepared particles according to Turkevich method. These factors include (reaction temperature, initial heating, concentration of gold ions, concentration and quantity of added citrate, reaction time and order of reactant addition). Gold nanoparticles prepared were characterized by the following measurements: UV-Visible spectroscopy, X-ray diffraction and scanning electron microscopy. The average size of gold nanoparticles was formed in the range (20 -35) nm. The amount of added citrate was changed and studied. In addition, the concentration of added gold ions was changed and the calibration cur
... Show MoreThis research deals with a very important subject as it tries to change the theoretical and scientific heritage and some professional rules adopted in the newsroom. Most media students have difficulties in writing news for press correctly. The researcher tries to identify the compatibility of what is published in local news agencies with professional and academic standards.
The research finds detailed editorial rules for a number of news formats which will play an important role in writing news for press easily, especially for the beginners and newcomers. Also, it discovers a new fact denying the beliefs of some researchers and writers in not having news conclusion in news edited according to the inverted pyramid pattern.
The re
In this study, we used Bayesian method to estimate scale parameter for the normal distribution. By considering three different prior distributions such as the square root inverted gamma (SRIG) distribution and the non-informative prior distribution and the natural conjugate family of priors. The Bayesian estimation based on squared error loss function, and compared it with the classical estimation methods to estimate the scale parameter for the normal distribution, such as the maximum likelihood estimation and th
... Show MoreThe aim of the thesis is to estimate the partial and inaccessible population groups, which is a field study to estimate the number of drug’s users in the Baghdad governorate for males who are (15-60) years old.
Because of the absence of data approved by government institutions, as well as the difficulty of estimating the numbers of these people from the traditional survey, in which the respondent expresses himself or his family members in some cases. In these challenges, the NSUM Network Scale-Up Method Is mainly based on asking respondents about the number of people they know in their network of drug addicts.
Based on this principle, a statistical questionnaire was designed to
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