NHPP-based software reliability model considering testing effort and multivariate fault detection rate

In recent decades,many software reliability growth models（SRGMs） have been proposed for the engineers and testers in measuring the software reliability precisely.Most of them is established based on the non-homogeneous Poisson process（NHPP）,and it is proved that the prediction accuracy of such models could be improved by adding the describing of characterization of testing effort.However,some research work indicates that the fault detection rate（FDR） is another key factor affects final software quality.Most early NHPPbased models deal with the FDR as constant or piecewise function,which does not fit the different testing stages well.Thus,this paper first incorporates a multivariate function of FDR,which is bathtub-shaped,into the NHPP-based SRGMs considering testing effort in order to further improve performance.A new model framework is proposed,and a stepwise method is used to apply the framework with real data sets to find the optimal model.Experimental studies show that the obtained new model can provide better performance of fitting and prediction compared with other traditional SRGMs.

Interaction of straight chain alcohol vapors with self-assembled MOF film by surface plasmon resonance sensing and imaging

Interaction of straight chain alcohol vapors with MOF-199-functionalized films was studied by SPR. The signals had linear relationships with the concentration of alcohols over a wide range from 0 to 70% （v/v） and were reversible in proportional to the chain length, with R2 all above 0.99.

Bacterial Sample Concentration and Culture Monitoring Using a PEG-Based Osmotic System with Inline Impedance and Voltammetry Measurements

Impedance measurements using graphite electrodes were used to detect the increase in culture medium conductivity due to bacteria growth in real time along with simultaneous voltammetric monitoring of pyocyanin concentration.Electrochemical methods were compared to conventional continuous monitoring of bacterial cultures using turbidity measurement at an optical density of 600 nm(OD600).A practical osmotic system was further designed for concentrating bacterial cultures during growth to enable earlier detection using the electrochemical methods.Bacterial cultures,starting from an initial culture density of 1×10^(8) cells/mL,were grown inside a sealed cellulose ester dialysis membrane,while polyethylene glycol in LB medium was used as the draw solution outside the membrane to gradually concentrate the growing cultures.0.7-mm-diameter graphite for mechanical pencils was utilized as working and counter electrodes with a platinum wire reference electrode for electrochemical measurements with and without the osmotic system.In the absence of forward osmosis,impedance meas-urements detected culture growth~1 h faster than conventional OD600.Integrating osmosis showed a twofold decrease in the time to detect pyocyanin production as an indicator for bacterial growth.For impedance monitoring,removal of water by osmosis was conflated with the impedance decrease due to cell growth;however,the results show a promising ability to detect bacteria growth via an observed shift in osmotic impedance profile when bacteria are present in a sample.By monitoring the deviation in the impedance profile,a threefold improvement in detection time was achieved when compared to conventional OD600 measurements.