A Branching Time Temporal Framework for Quantitative Reasoning

Temporal logics such as Computation Tree Logic (CTL) and Linear Temporal Logic (LTL) have become popular for specifying temporal properties over a wide variety of planning and verification problems. In this paper we work towards building a generalized framework for automated reasoning based on temporal logics. We present a powerful extension of CTL with first-order quantification over the set of reachable states for reasoning about extremal properties of weighted labeled transition systems in general. The proposed logic, which we call Weighted Quantified Computation Tree Logic (WQCTL), captures the essential elements common to the domain of planning and verification problems and can thereby be used as an effective specification language in both domains. We show that in spite of the rich, expressive power of the logic, we are able to evaluate WQCTL formulas in time polynomial in the size of the state space times the length of the formula. Wepresent experimental results on the WQCTL verifier.     

Scattering by a perfectly conducting and a coated thin wire using aphysical basis model

A traveling-wave model is used in conjunction with a Galerkin's solution of the exact integral equation to solve for the scattering by a thin perfectly conducting and a thin dielectrically coated wire. The proposed current model consists of three weighted traveling-wave components; one is associated with the current on the infinite wire whereas the other two describe the reflected traveling waves from the wire terminations. Several current distribution and scattering patterns are presented which serve to validate the accuracy of the model and the derived analytical formulas     

Deactivation of metal exchanged zeolite catalysts during exposure to chlorinated hydrocarbons under oxidizing conditions

Deactivation of modified cation exchanged zeolite catalysts was studied during complete oxidation of methylene chloride, trichloroethylene and carbon tetrachloride over a temperature range of 175 to 400°C. Coking was found to be the cause of deactivation. However, the catalysts could be completely regenerated by oxidation in air at 450°C. Two different formulations of modified cobalt exchanged Y zeolite catalysts were tested to determine the coking and deactivation rates. Increased cation content increased deactivation and coking over a period of about 1000 hours. Changing the type of zeolite from larger pore Y to medium pore mordenite increased deactivation. The type of chlorinated feed also affected coking and deactivation with the rate of deactivation increasing in the order of trichloroethylene> methylene chloride> carbon tetrachloride. Both coking and deactivation increased with decreasing temperature. Higher space velocity produced more deactivation for trichloroethylene oxidation at 275°C. Based on these results a mechanism for coking is proposed with CO as the possible reaction intermediate that leads to the formation of coke.     

Evaluation of argyrophilic nucleolar organizer regions (AgNORs) in oral carcinomas in relation to human papillomavirus infection and cytokinetics

The numbers of argyrophilic nucleolar organizer regions (AgNORs) were quantified in oral carcinomas (n = 39) with or without human papillomavirus (HPV) infection. The AgNOR counts of the HPV-positive samples (7.15 +/- 2.13) were not significantly (P = 0.09) higher than those of the HPV-negative ones (6.16 +/- 1.89). Furthermore, the lesions infected with multiple HPV types had greater counts than those with HPV type 16/18 infection alone. Significant differences were observed between the mean counts of the poorly (10.50 +/- 0.54), moderately (7.31 +/- 1.07) and well- (5.12 +/- 0.85) differentiated carcinomas. The mean AgNOR numbers in the oral carcinomas at TNM stages III/IV were found to be significantly (P < 0.01) higher than the numbers in corresponding stage II lesions. Cytokinetics of the lesions assessed by the bromodeoxyuridine (Brdu) labelling index (LI%) showed a linear correlation (r = 0.91; P < 0.0001) with their respective mean AgNOR counts.     

Stability of Silicate Coatings on Pyrite Surfaces in a Low pH Environment

The suppression of pyrite oxidation due to the formation of stable coatings of Fe3+–silica and/or Fe3+–hydroxy–silica complexes over pyrite surfaces in near-neutral and neutral solution pHs is well documented. On the contrary, there is currently no convincing experimental evidence that proves the existence of such a coating under low pH environments. Aqueous continuous flow kinetic experiments were conducted using coating solutions containing Na2SiO3?5H2O and H2O2 at pH 6, 4, 3, and 2. Results showed that at pH 2, pyrite oxidation in the presence of silica is pseudofirst order and oxidation is not inhibited by silica. At pH 6, silica significantly reduced pyrite oxidation via a pseudofirst-order reaction that takes on several stages related to changes in the relative contributions of H2O2 and Fe3+. Iron speciation data suggests a surface adsorption mechanism at pH 6 and an electrochemical mechanism at pH 2 for pyrite oxidation. Scanning electron microscopy and energy dispersive x-ray spectroscopy also support the kinetic model and showed the absence of any significant silica coating at pH 2.     

Electrochemical Study of Diffusion Bonded Joints between Micro-duplex Stainless Steel and Ti6A14V Alloy

In the present study,corrosion behavior of diffusion bonded joints formed between micro-duplex stainless steel(MDSS) and Ti6AI4V alloy(TiA)(at 900 ℃ for 60 min under 4 MPa uniaxial pressure in vacuum) was investigated in 1 mol/L HCI and 1 mol/L NaOH solutions using various electrochemical measurements such as open circuit potential(OCP),electrochemical impedance spectroscopy(EIS) and potentiodynamic polarization(PD).For comparison,corrosion behavior of base metals(MDSS and TiA) was also evaluated.Bonded joint was characterized by light optical microscopy and scanning electron microscopy using backscattered electron mode.The layer wise σ phase and λ + FeTi phase mixture has been observed at the bond interface and the bond tensile strength and shear strength were ~556.4 MPa and ~420.2 MPa,respectively.     

A novel DSP‐based PFC‐DPLL with fuzzy controlled acquisition aid to improve acquisition performance and noise immunity

This paper proposes a new digital signal processing (DSP)‐based phase frequency controlled digital phase locked loop. Here, a very simplistic form of fuzzy logic controller with the help of carrier phase and frequency error as input data is used to provide an acquisition aid. A frequency discriminator is employed to generate frequency error, and phase detector output is taken for phase error. This addition of an acquisition aid helps the loop to achieve the minimum acquisition time and maximum noise rejection simultaneously. An additional phase control in the digitally controlled oscillator makes the loop perform even better towards this goal. The implementation of the proposed loop is carried out on a reconfigurable logic platform using System Generator^®;, a tool from Xilinx^®; used to design real‐time DSP application. A significant improvement of time domain characteristics are observed as well as the performance in presence of additive white Gaussian noise is demonstrated in terms of the reduction in steady‐state phase jitter and enhancement in output signal to noise ratio in the proposed loop. Copyright © 2014 John Wiley & Sons, Ltd.     

Thermoelectric cold-chain chests for storing/transporting vaccines in remote regions

The cold chain is one of the key elements of the preventive health-care delivery system. Vaccines have to be carried long distances, stored in remote places and during this period the temperature has to be maintained within certain specified values. Realizing the needs of such requirements, the Department of Science & Technology, New Delhi (Govt. of India) assigned a project to the R&D Division of MECON, Ranchi for development of Thermoelectric Cold-Chain Chest operated by 12 V DC vehicular battery. The resulting portable thermoelectric (i.e. Peltier effect) Cold-Chain Chest (TCC) operated successfully even in an ambient environment of 45 °C, mainly for preserving and transporting life-saving medicines for urban as well as rural areas.