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In Iran, People Who Inject Drugs (PWID), Female Sex Workers (FSW), and prisoners are the main key populations at risk of HIV infection. This study aimed to evaluate the trend of HIV incidence among PWID, FSW and prisoners as an impact measure of HIV harm reduction and prevention efforts in Iran. Data were obtained from the two rounds of national bio-behavioral surveillance surveys among FSW (2010

The use of this material under current conditions is supported by existing information. 1,1-Diethoxyheptane was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from the read-across analog octanal dimethyl acetal (CAS # 10022-28-3) show that 1,1-diethoxyheptane

Nowadays, we live in a society with billions of devices that are interconnected and interact together to improve the quality of our lives. The management and processing of information and knowledge have by now become our main resources, and the fundamental factors of economic and social development, and it is achieved through Big Data Frameworks (BDFs). The amount of such data is becoming larger e

The operator Riccati equation associated with a distributed parameter quadratic cost-linear dynamics control process is considered.Making use of ideas from transport theory, a derivation of a generalized version of the X-Y functions of radiative transfer is given, and it is seen that, under commonly occurring conditions, the new equations may be easier to numerically resolve than the original Ricc

In this paper some of the numerical problems associated with computing the generalized inverse of a matrix are discussed and illustrated by a detailed analysis of an iteration of Ben-Israel and Cohen.

The problem of identifiability of processes using measurements obtained under closed loop operation is treated. Single input-single output systems are considered. It is assumed that the feedback is time invariant, linear and noise free. It is also assumed that no external input signal is injected. Conditions, which are simultaneously necessary and sufficient for identifiability are derived. The re

Tin whiskers are hair-like single crystals that spontaneously grow from tin-coated surfaces. Whiskers are commonly found in electronic components, where tin coatings are used in, e.g., soldering applications, and to protect components from corrosion. Whiskers are known to cause short-circuits leading to failure of electronic components. The exact mechanisms responsible for whisker formation and gr

In this paper five different recursive identification methods will be analyzed and compared, namely recursive versions of the least squares method, the instrumental variable method, the generalized least squares method, the extended least squares method and the maximum likelihood method. They are shown to be similar in structure and need of computer storage and time. Making use of recently develop

A class of identification methods, proposed in [3], are based on the instrumental variable principle. This correspondence contains a continued analysis of convergence of the parameter estimates of these methods. Alternative, sufficient conditions for convergence to correct values are given. It is also shown by construction of counter-examples that the methods do not converge under general conditio

ERP systems became popular with large organizations in the 1990s. In the 21st Century, these products were expanded by addition of supply chain management (SCM) and customer relationship management (CRM), as well as access through the Web, creating the ERP II concept. Efforts to increase the market led vendors to serve not only large organizations, but also focus more on small-to-medium sized ente

Applications of the generalized least squares method proposed by Clarke [1] have been reported by various authors. However, no analysis of the convergence of the method has been published. This correspondence gives examples for which the method converges to false solutions.

Convergence properties of the generalized least squares method are analyzed. The method can be interpreted as optimization of a likelihood function. The number of local maximum points of the likelihood function is examined. It is shown that this number is influenced by the signal to noise ratio. This theoretical result is illustrated by numerical examples using plant measurements. It is also prove

The current study demonstrates through experiment, the effect of solid lubricant assisted minimum quantity cooling lubrication (MQCL) when turning tempered (~60 HRC) alloyed steel Uddeholm Caldie with cemented carbide tools on the process performance. In MQCL application, nanosized graphite nanoplatelets (GnP) solid lubricant powder was dispersed (0.2% vol.) in rapeseed oil based lubricant “ECOLUB

The maximum likelihood method of identification is a powerful tool for obtaining mathematical models of dynamic processes. To apply this method a loss function has to be minimized. The aim of the paper is an investigation of the local minimum points of this loss function for a common structure of a general form. If the loss function has more than one local minimum point, numerical problems can occ

The presence of graphite particles in gray cast iron commonly implies a good machinability, especially if compared to common steels. However, increasing industrial demands have resulted in a new interest for high-speed machining of these materials with higher performing tool materials than the traditionally used. Thus, the research presented in this paper focuses on evaluating the active tool wearThe presence of graphite particles in gray cast iron commonly implies a good machinability, especially if compared to common steels. However, increasing industrial demands have resulted in a new interest for high-speed machining of these materials with higher performing tool materials than the traditionally used. Thus, the research presented in this paper focuses on evaluating the active tool wear

Aim of the Study. To assess the frequency of and identify contributing factors to wound dehiscence after posterior sagittal anorectoplasty (PSARP) in children born with anorectal malformations (ARM). Methods. Ethical approval was obtained (DNR 2017/191). Charts of all children with anorectal malformations (ARM) reconstructed with PSARP, limited PSARP, or PSARVUP at a tertiary centre of paediatric

Objective: In the 2016 American College of Rheumatology/European League Against Rheumatism classification criteria for primary Sjögren’s syndrome (pSS), pre-existing lymphoma is not an exclusion criterion for pSS diagnosis, as in earlier criteria. We aimed to explore whether there are differences between pSS patients with and without pre-existing lymphoma at pSS diagnosis. Method: Patients with IC

To Ask for the King’s Permission to Marriage: Applications for Marriage between Relatives in Eighteenth Century Sweden. In early modern Western society regulations against incestuous relationships were primarily justified by religion, and kinship by blood and kinship by marriage were treated equally. In the seventeenth and eighteenth centuries Swedish law was among the strictest in these matters,