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AbstractThe problem of comparing the means of two independent Poisson distributions has been addressed in the literature. A generalization of the Poisson distribution to accommodate over- and under-dispersion in the data is the two-parameter Poisson distribution developed by Conway and Maxwell. This distribution has nice properties, and it includes geometric, Poisson and binomial distributions as its special cases. The present work considers the problem of comparing the means of two independent reparametrized Conway-Maxwell Poisson distributions assuming the dispersion parameter to be known. The proposed test procedures make use of the conditional, exact, asymptotic and likelihood ratio test approaches. The test statistic under various approaches is derived, and the respective powers and effect sizes are evaluated and compared through a simulation study. A numerical illustration of the applicability of the tests is provided through real-life data. [ABSTRACT FROM AUTHOR]

This paper describes radio frequency identification (RFID) projects, designed and implemented by students in the College of Engineering at the University of North Texas, as part of their senior-design project requirement. The paper also describes an RFID-based project implemented at Rice Middle School in Plano, TX, which went on to win multiple prizes both at the school and regional level. The goal of the RFID endeavor is to develop an RFID elective course that is current, industry-oriented, and methodically built to enable faculty to design, develop, and deliver the course to a diverse group of engineering students. The sequence of events through which the course evolved was as follows: 1) conduct an industry-supported workshop for students in the College of Engineering with funding received from the National Science Foundation (NSF); 2) assign an RFID-based design project for the senior students who attended the workshop; 3) use the first senior design project as a model to encourage subsequent senior students to create their own RFID projects or enable the students to contact companies seeking to accomplish RFID solutions to a problem; 4) involve middle school students in RFID-based projects by using the senior design projects as an enticement; 5) use the successful projects as the basis for practical laboratory experiences to be created in a new elective course on RFID. (Contains 4 figures.)

A study on the examination of morphological defects in 4H-SiC and defects visible in electron beam-induced current (EBIC) images and their effects on the electrical characteristics of Schottky diodes were carried out. The results shows that most of the morphological defects do not affect the reverse characteristic when no micropipes are present, but lower the barrier height and worsen the ideality factor.

In this paper, by considering an M|M|1|1 queueing model, Bayesian estimation of traffic intensity and measures of system performance are worked out under the squared error loss function (SELF) based on the observed data on independent interarrival and service times. Further, minimum posterior risk associated with Bayes estimators of traffic intensity and system performance measures are obtained under SELF. Numerical illustration of the performance of the estimates is given through simulation study. It is shown that Bayes estimators perform better than the maximum likelihood estimators under the influence of prior informations. [ABSTRACT FROM AUTHOR]

By considering an M | D | 1 queueing system, the maximum likelihood and consistent estimators of traffic intensity are derived by observing the number of entity arrivals during the service time of an entity. Uniform minimum variance unbiased estimators for the expected waiting times per entity in the system and queue are obtained. Further, Bayes estimators of traffic intensity, measures of system performance, minimum posterior risk, and minimum Bayes risk associated with these estimators are derived. Also, the Bayes estimator of traffic intensity and its risk function are derived under LINEX loss function. [ABSTRACT FROM AUTHOR]

In literature, Lindley distribution is considered as an alternative to exponential distribution to fit lifetime data. In the present work, a Lindley step-stress model with independent causes of failure is proposed. An algorithm to generate random samples from the proposed model under type 1 censoring scheme is developed. Point and interval estimation of the model parameters is carried out using maximum likelihood method and percentile bootstrap approach. To understand the effectiveness of the resulting estimates, numerical illustration is provided based on simulated and real-life data sets. [ABSTRACT FROM AUTHOR]

Defects in SiC degrade the electrical properties and yield of devices made from this material. This article examines morphological defects in 4H–SiC and defects visible in electron beam-induced current (EBIC) images and their effects on the electrical characteristics of Schottky diodes. Optical Nomarski microscopy and atomic force microscopy were used to observe the morphological defects, which are classified into 26 types based on appearance alone. Forward and reverse current–voltage characteristics were used to extract barrier heights, ideality factors, and breakdown voltages. Barrier heights decrease about linearly with increasing ideality factor, which is explained by discrete patches of low barrier height within the main contact. Barrier height, ideality, and breakdown voltage all degrade with increasing device diameter, suggesting that discrete defects are responsible. Electroluminescence was observed under reverse bias from microplasmas associated with defects containing micropipes. EBIC measurements reveal several types of features corresponding to recombination centers. The density of dark spots observed by EBIC correlates strongly with ideality factor and barrier height. Most morphological defects do not affect the reverse characteristics when no micropipes are present, but lower the barrier height and worsen the ideality factor. However, certain multiple-tailed defects, irregularly shaped defects and triangular defects with 3C inclusions substantially degrade both breakdown voltage and barrier height, and account for most of the bad devices that do not contain micropipes. Micropipes in these wafers are also frequently found to be of Type II, which do not run parallel to the c axis. [ABSTRACT FROM AUTHOR]

The development of any probe to detect cluster adducts requires an in depth understanding on the binding affinity of probes to these adducts. In this context, we attempted to study the interaction of known DNA molecular switch [Ru(phen)2(dppz)]2+ with mono‐ and cluster DNA adducts in 16‐mer NarI sequence (5′‐CTCTCG1G2CG3CCATCAC‐3′) where guanine bases are modified with N‐acetyl‐2‐aminofluorene(AAF). Luminescence studies show that [Ru(phen)2(dppz)]2+ (phen: 1,10‐phenanthroline and dppz: dipyrido[3,2‐a:2′,3′‐c]phenazine) binds to AAF adduct at G1 and G3 which possesses minor‐groove(W) and stacked conformation(S) exhibit two fold enhancement while G2 with major groove B‐conformer exhibit 1.6 fold enhancement when compared to control. In diadducts, RuII binds to G2G3 AAF adduct lower than that of other two diadducts G1G3 and G1G2. With triadducts, phenazine moiety of RuII complex adopts canted geometry to the DNA due to the very unstable structure at the adducted site. From microscale thermophoretic data, the kd of RuII was determined and found to be consistent with luminescence data. The present study provides an overall insight of role of conformation of AAF structure embedded in different sequence context that dictates the sensitivity of the DNA molecular light switch, in turn, facilitates in developing highly efficient probe to distinguish these cluster adducts. [Ru(phen)2(dppz)]2+ differentiates the binding with mono‐ and cluster arylamine‐DNA adducts in a conformation‐specific manner. RuII complex sensitize the stacked conformer (S) of acetylaminofluorene DNA adduct better compared to major groove conformer(B). [ABSTRACT FROM AUTHOR]

Abstract The authors used mesoporous silica microspheres as a support for the immobilization of inulinase from Aspergillus brasiliensis MTCC 1344 by the process of cross‐linking. Under optimized operating conditions of pH 6.0, particle/enzyme ratio of 2.0:1.0 and glutaraldehyde concentration of 7 mM, a maximum immobilization yield of 90.7% was obtained after a cross‐linking time of 12.25 h. Subsequently, the cross‐linked inulinase was utilized for the hydrolysis of 5% inulin, and a maximum fructose concentration of 31.7 g/L was achieved under the optimum conditions of pH 6.0 and temperature 60°C in 3 h. Furthermore, on performing reusability studies during inulin hydrolysis, it was observed that the immobilized inulinase could be reused up to 10 subsequent cycles of hydrolysis, thus providing a facile and commercially attractive process of high‐fructose syrup production.

Statistical analysis of standby systems with more than two units has received little attention because of mathematical intricacies involved in analyzing them. Also, such systems have been studied assuming the lifetime and repair time of the units to be independent. The present article is an attempt to study certain inferential aspects of a three unit hot standby system with dependent structure, assuming quadrivariate exponential distribution for the lifetimes of online unit, standby units and the repair time of a failed unit. [ABSTRACT FROM AUTHOR]