module over a ring is a general mathematical concept for many examples of mathematicalobjects that can be added to each other and multiplied by scalar numbers.in this paper, we consider a module over a ring as a universe and by using the notion of reference points, we provide local approximations for  subsets of the universe.

background and objective: improved and modified automation will require the development of smart process control systems that provide on-line decisions to release patients’ test results based on high analytical quality assurance formula. materials and methods: we collected patients’ test results from 10840 healthy subjects based on 1.96z as truncation limit for 29 common haematochemical analyte...

background : medical x-rays are the largest man-made source of public exposure to ionizing radiation. while the benefits of computed tomography (ct) are well known in accurate diagnosis, those benefits are not risk-free. ct is a device with higher patient dose in comparison with other conventional radiation procedures. objective: this study is aimed at evaluating radiation dose to patients from...

data envelopment analysis (dea) was developed to help compare the relative performance of decision-making units. it is a non-parametric method for performing frontier analysis. it uses linear programming to estimate the efficiency of multiple decision-making units and it is commonly used in production, management and economics [3]. dea generates an efficiency score between 0 and 1 for each unit...

abstract reference evapotranspiration (eto) is an essential parameter required for proper management of agricultural crop irrigation. eto is influenced by many different hydrological variables and as a result is a very complex procces. eto is usually estimated by empirical or process-orinented models (mathematical relationships) from historical weather data. the need for accurate estimates of e...

background: dna isolation procedure can significantly influence the quantification of dna by real time pcr specially when cell free dna (cfdna) is the subject. to assess the extraction efficiency, linearity of the extraction yield, presence of co-purified inhibitors and to avoid problems with fragment size relevant to cfdna, development of appropriate external dna control (edc) is challenging. ...

introduction the present work describes a study in which, based on patient dose measurements, thermoluminescent dosimeters were used to obtain the diagnostic reference level arising from panoramic radiography. materials and methods ten panoramic units and a sample of 15 patients per x-ray unit were studied. two thermoluminescent dosimeter chips were placed on the skin surface of selected organs...

low frequency noise (lfn) is ubiquitous in both occupational and general environments. mental performance of subjects exposed to lfn is expected to be impaired. individual characters seem to play a significant role in this process. this study aimed to evaluate the effects of moderate levels of lfn (20–200 hz) on mental performance. fifty-three subjects (in two groups) were exposed to low and fl...