A new equivalent circuit for inverters and its application for the determination of coupling matrix elements of narrow RF bandpass filters

A new equivalent circuit for inverters is presented. Using this circuit, expression for the elements of the coupling matrix of narrow RF band pass filters is derived. The derivation is based on frequency independent coupling assumed in the synthesis of narrow RF band pass filters. Our expression is different from an earlier expression obtained using lumped circuit representations of different types of coupling and their analysis. It is shown that the earlier expression can be derived from our analysis if the coupling is assumed frequency‐variant. Unlike earlier work, our derivation shows how the sign of the coupling coefficient can be obtained. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010.     

Taxol induces bcl-2 phosphorylation and death of prostate cancer cells

Treatment of prostate cancer cell lines expressing bcl-2 with taxol induces bcl-2 phosphorylation and programmed cell death, whereas treatment of bcl-2-negative prostate cancer cells with taxol does not induce apoptosis. bcl-2 phosphorylation seems to inhibit its binding to bax since less bax was observed in immunocomplex with bcl-2 in taxol-treated cancer cells. These findings support the use of the anticancer drug taxol for the treatment of bcl-2-positive prostate cancers and other bcl-2-positive malignancies, such as follicular lymphoma.     

Cyberloafing in the workplace: mitigation tactics and their impact on individuals’ behavior

With the Internet permeating every aspect of daily life, organizations of all types are increasingly concerned about the degree to which their employees are cyberloafing by shirking their work responsibilities to surf the Internet, check e-mail, or send text messages. Although technological interventions against cyberloafing have been shown to be effective, they might be perceived by employees as an invasion to their privacy, and are expected to have repercussions on employee behavior and loyalty. The main objectives of this study are to (1) examine how the introduction of such technological interventions might affect employees’ emotions and fairness perceptions, and (2) understand the effect of the interventions on behavioral outcomes, i.e., employees’ intentions to cyberloaf and their loyalty to the company. We developed a justice-based framework that we empirically test using a field experiment composed of field surveys complemented with hypothetical scenarios describing new organizational initiatives to curb employees’ cyberloafing. Our findings suggest that technological interventions, although associated with perceptions of unfairness, are effective at controlling cyberloafing, albeit at the expense of employee loyalty. On the other hand, contrary to prior findings, we find that fairness perceptions of technological interventions, although reinforcing employee loyalty, are ineffective at curbing cyberloafing. These findings are especially enlightening in that they contradict a common belief that perceived fairness encourages employees, as a sign of their appreciation for this fairness, to curb their misuse of IT. The findings also help managers fine-tune their cyberloafing policies to achieve a long-lasting remedy to their employees’ cyberloafing while maintaining a necessary level of employee loyalty.     

Strategic Conversations Under Imperfect Information: Epistemic Message Exchange Games

This paper refines the game theoretic analysis of conversations in Asher et al. (J Philos Logic 46:355–404, 2017) by adding epistemic concepts to make explicit the intuitive idea that conversationalists typically conceive of conversational strategies in a situation of imperfect information. This ‘epistemic’ turn has important ramifications for linguistic analysis, and we illustrate our approach with a detailed treatment of linguistic examples.     

Characterisation of electric current-treated austenite using misorientation angle distributions in martensite

ABSTRACT

The angle misorientation distribution of martensite formed from electric current treated and non-treated austenite samples are studied using electron backscatter diffraction. The electric currents are pulsed with a loading width of 80 μs, at a frequency of 100?Hz and current density of 4.21 A/mm² supplied by a DC Voltage. The majority of angle misorientations are < 5° and exist within the martensite grains, while only a minority of all misorientations are derived from the prior austenite grain boundary and were found to lie in the range 20–50°. Distinct textures develop in both electric current treated and non-treated samples with increased quenching temperature. Analysis of the prior austenite shows reduced grains in the electric current treated samples at all quenching temperatures considered.

This paper is part of a themed issue on Materials in External Fields.     

Nighttime visual refinement techniques for surveillance video: a review

Video surveillance systems substitute manual efforts in various safety critic domains such as border area, assisted living, banking, service stations, and transportation. The multimedia-based surveillance system has a significant role in security and forensic systems because people tend to be easily convinced after observing voice, image, and video. Hence, these videos are strong evidence in the forensic investigation. However, most of the criminal activities such as ATM robbery and assassination are occur at nighttime because of the crime supporting dark environment. Many of the night surveillance systems in military, as well as commercial applications, are equipped with infrared and thermal based night vision systems. Its poor capability of texture and color interpretations are the major issues to ensure secure nighttime video monitoring. Specifically, visual refinements of nighttime surroundings and foreground objects provide a valuable assistance in the nighttime security system. In this scenario, it is highly recommended a review of the state-of-the-art nighttime visual refinement approaches. We conducted an extensive literature review and classified the nighttime visual refinement approaches into nighttime restoration and enhancement. This comparative literary analysis identified the research gap fields to explore future research directions in nighttime visual enhancement techniques. Finally, we discussed various open issues and future directions in the context enhancement based nighttime enhancement research.

     

Effect of nano CuO addition on the tribo-mechanical behavior of alumina ceramics in non-conformal contact

Sintering of alumina from 1500°C to 1650°C and tribo-mechanical properties at room temperature had been investigated using nano CuO as a sintering aid. Bulk density gradually increases with sintering temperature from 1500°C to 1600°C and is optimized at 1600°C, beyond this, bulk density does not significantly increase at 1650°C. The addition of 2 wt% CuO showed the best result on densification. Densification of about 97.74% was attained at 1600°C with the incorporation of 2 wt% CuO. Nano CuO at grain boundaries forms CuAl₂O₄ liquid which modifies the morphology of the grain and improves mechanical properties. The formation of self-lubricating tribo-film on the wear track results in a low coefficient of friction <0.2 and reduces specific wear rate. 4 wt% CuO addition increases contact tensile stress (σ_max) by 51.2% and high Hertzian contact pressure (P_max≈1.51 GPa) causes plastic deformation of wear track. The re-solidified strengthening bond phase on the wear track simultaneously increases in friction coefficient and wear resistance with CuO addition. The optimizing effect of CuO addition shows that 2 wt% significantly decreases wear rate, and increases hardness and fracture toughness.     

Electrochemical oxidation behavior of titanium nitride based electrocatalysts under PEM fuel cell conditions

Titanium nitride (TiN) is attracting attention as a promising material for low temperature proton exchange membrane fuel cells. With its high electrical conductivity and resistance to oxidation, TiN has a potential to act as a durable electrocatalyst material. Using electrochemical and spectroscopic techniques, the electrochemical oxidation properties of TiN nanoparticles (NP) are studied under PEM fuel cell conditions and compared with conventional carbon black supports. It is observed that TiN NP has a significantly lower rate of electrochemical oxidation than carbon black due to its inert nature and the presence of a native oxide/oxynitride layer on its surface. Depending on the temperature and the acidic media used in the electrochemical conditions, the open circuit potential (OCP) curves shows the overlayer dissolved in the acidic solution leading to the passivation of the exposed nitride surface. It is shown that TiN NP displays passive behavior under the tested conditions. The XPS characterization further supports the dissolution argument and shows that the surface becomes passivated with the O-H groups reducing the electrical conductivity of TiN NP. The long-term stability of the Pt/TiN electrocatalysts is tested under PEM fuel cell conditions and the trends of the measured electrochemical surface area at different temperatures is shown to agree with the proposed passivation model.