A consecutive k-out-of-n:G system with dependent elements—a matrix formulation and solution

The reliability of a consecutive k-out-of-n:G system is studied. The system may involve dependent trials, so that the probability of success of a certain test is increased after carrying out corrective actions. The problem is solved via a matrix formulation, using state space methods. Results are shown to correlate for the case of independent trials with those in the literature.     

Combined k-out-of-n:G, and consecutive k/sub c/-out-of-n:G systems

Qualification tests for a system are normally carried out according to either a k-out-of-n:G scheme, or a consecutive k/sub c/-out-of-n:G structure. The reliability of a combination of the two systems is evaluated, showing its benefit over each of the individual structures. As expected, the mean time to failure of the combined system is larger than any of them. Generalizations of the analysis are presented for tests with multi-state results, and for dependent tests. Illustrative numerical results are presented to substantiate the theory.     

Lifetime modelling with aid of a modified complementary weibull distribution

The complementary Weibull distribution may serve as a lifetime model for various applications. A modification of this distribution is introduced. Its purpose is to enable the calculation of the MTBF integral, which does not exist for the regular complementary Weibull function. An efficient quadrature technique is provided. Its utility is validated through some examples.     

Use of intelligent sensors and software radio technologies foroptimal design of reconfigurable multimedia surveillance networks

In these last years, the increasing request for security coming from civil society led to intensive exploitation of the most advanced technological tools for solving problems related to remote monitoring of public sites. New-generation multimedia surveillance systems will be characterized by such key topics as distribution of processing capabilities among intelligent sensor and central processing levels, and dynamic reconfigurability of the wireless links thanks to innovative software radio technologies. In this work a joint analysis of such aspects is presented in order to provide optimal design strategies for new-generation multimedia surveillance networks, able to take into account the trade-offs between available computing and communications resources and required performance in terms of correct event detection and real-time processing     

Intelligent Cloud IoMT Health Monitoring-Based System for COVID-19

The most common alarming and dangerous disease in the world today is the coronavirus disease 2019 (COVID-19). The coronavirus is perceived as a group of coronaviruses which causes mild to severe respiratory diseases among human beings. The infection is spread by aerosols emitted from infected individuals during talking, sneezing, and coughing. Furthermore, infection can occur by touching a contaminated surface followed by transfer of the viral load to the face. Transmission may occur through aerosols that stay suspended in the air for extended periods of time in enclosed spaces. To stop the spread of the pandemic, it is crucial to isolate infected patients in quarantine houses. Government health organizations faced a lack of quarantine houses and medical test facilities at the first level of testing by the proposed model. If any serious condition is observed at the first level testing, then patients should be recommended to be hospitalized. In this study, an IoT-enabled smart monitoring system is proposed to detect COVID-19 positive patients and monitor them during their home quarantine. The Internet of Medical Things (IoMT), known as healthcare IoT, is employed as the foundation of the proposed model. The least-squares (LS) method was applied to estimate the linear model parameters for a sequential pilot survey. A statistical sequential analysis is performed as a pilot survey to efficiently collect preliminary data for an extensive survey of COVID-19 positive cases. The Bayesian approach is used, based on the assumption of the random variable for the priori distribution of the data sample. Fuzzy inference is used to construct different rules based on the basic symptoms of COVID-19 patients to make an expert decision to detect COVID-19 positive cases. Finally, the performance of the proposed model was determined by applying a four-fold cross-validation technique.     

Acoustic remote sensing of the boundary layer

An acoustic echo sounder (called sodar) has been developed, designed and fabricated. This equipment has been operating successfully for several years and has been shown to have important applications in the areas of air pollution control/studies, microwave and millimetre wave radio communication including troposcatter, aviation and micrometeorology. Work on the development of the sodar was taken up at the National Physical Laboratory (npl) in 1972. At that time, this was one of the few equipment of its kind in the world. It has been designed in the laboratory and has been built with indigenous components. The equipment currently probes the thermal structure of the atmosphere upto a height of 700 m but can be extended to a kilometre. Two sodars are in operation-one at the National Physical Laboratory, Delhi and the other at the Micrometeorological Laboratory, Tarapur in collaboration with barc, Bombay. The design criteria of the npl sodar and experiments with it are described in this paper. We believe that the technique will soon become an important tool in the areas of micrometeorology, radio communication, aviation and air pollution studies.     

Discovery of Inhibitors of Trypanosoma brucei by Phenotypic Screening of a Focused Protein Kinase Library

A screen of a focused kinase inhibitor library against Trypanosoma brucei rhodesiense led to the identification of seven series, totaling 121 compounds, which showed >50 % inhibition at 5 μm . Screening of these hits in a T. b. brucei proliferation assay highlighted three compounds with a 1H‐imidazo[4,5‐b]pyrazin‐2(3H)‐one scaffold that showed sub‐micromolar activity and excellent selectivity against the MRC5 cell line. Subsequent rounds of optimisation led to the identification of compounds that exhibited good in vitro drug metabolism and pharmacokinetics (DMPK) properties, although in general this series suffered from poor solubility. A scaffold‐hopping exercise led to the identification of a 1H‐pyrazolo[3,4‐b]pyridine scaffold, which retained potency. A number of examples were assessed in a T. b. brucei growth assay, which could differentiate static and cidal action. Compounds from the 1H‐imidazo[4,5‐b]pyrazin‐2(3H)‐one series were found to be either static or growth‐slowing and not cidal. Compounds with the 1H‐pyrazolo[3,4‐b]pyridine scaffold were found to be cidal and showed an unusual biphasic nature in this assay, suggesting they act by at least two mechanisms.     

Bradykinin antagonists in human systems: correlation between receptor binding, calcium signalling in isolated cells, and functional activity in isolated ileum

The determination of the relationship between ligand affinity and bioactivity is important for the understanding of receptor function in biological systems and for drug development. Several physiological and pathophysiological functions of bradykinin (BK) are mediated via the B2 receptor. In this study, we have examined the relationship between B2 receptor (soluble and membrane-bound) binding of BK peptidic antagonists, inhibition of calcium signalling at a cellular level, and in vitro inhibition of ileum contraction. Only human systems were employed in the experiments. Good correlations between the studied activities of BK antagonists were observed for a variety of different peptidic structures. The correlation coefficients (r) were in the range of 0.905 to 0.955. In addition, we analyzed the effect of the C-terminal Arg9 removal from BK and its analogs on B2 receptor binding. The ratios of binding constants (Ki(+Arg)/Ki(-Arg)) for the Arg9 containing compounds and the corresponding des-Arg9 analogs varied from about 10 to 250,000. These ratios strongly depend on the chemical structures of the compounds. The highest ratios were observed for two natural agonist pairs, BK/des-Arg9-BK and Lys0-BK/des-Arg9-Lys0-BK.