A challenge when using current magnetic resonance (MR)-based attenuation correction in positron emission tomography/MR imaging (PET/MRI) is that the MRIs can have a signal void around the dental fillings that is segmented as artificial air-regions in the attenuation map. For artifacts connected to the background, we propose an extension to an existing active contour algorithm to delineate the o...

Real-time magnetic resonance imaging (RT-MRI) is a powerful tool to study the dynamics of vocal tract shaping during speech production. The dynamic articulators of interest include the surfaces of the lips, tongue, hard palate, soft palate, and pharyngeal airway. All of these are located at air-tissue interfaces and are vulnerable to MRI off-resonance effect due to magnetic susceptibility. In R...

absorption spectrometer with Zeeman background correction, which eliminates the effect of interfering impurities. It is the only high sensitivity and selectivity instrument that does not require gold amalgam pre-concentration and subsequent regeneration steps. This enables the user to conduct real time monitoring and detection of a mercury vapor. Being combined with an RP-91 Cold Vapor accessor...

Silicones are an important class of hydrophobic compounds in widespread use. To evaluate their fate in the environment, an accurate value of the air-water partition (Henry's law) constant is necessary, which, unfortunately, is lacking at present. A static head space and a newly developed dynamic vapor entry loop method were used to obtain the air-water partition constant for six volatile methyl...

The events of September 11, 2001, have raised troubling questions regarding the reliability and security of American commercial air travel. This article applies the concepts and logic of highreliability organizations to airport security operations. Contemporary decision theory is built on the logic of limited or buffered rationability and is based on the study of error-tolerant organizations. T...

Laser induced fluorescence is used to develop a 2D measurement technique for mixture formation analysis of fuel and air in a broad temperature regime from 398 K up to 548 K. The measurement principle is called FARLIF (fuel-air ratio by laser-induced fluorescence). Its application is tested on the tracer toluene in the non-fluorescent model fuel isooctane as well as on an auto-fluorescing nearst...

background: measuring and monitoring of air pollutants are one of environmental and all' pollution controls tools. due to lack of widespread data in iran, this study was performed to estimate the trends of major pollutant emissions to atmosphere in the uk from 1980 to 1996. methods: this investigation is a retrospective study that the data were collected from the departments of environment, tra...

Abstract. An upper-air simulator (UAS) has been developed at the Korea Research Institute of Standards and Science (KRISS) to study effects solar irradiation commercial radiosondes. In this study, uncertainty in radiation correction a Vaisala RS41 temperature sensor is evaluated using UAS KRISS. First, environmental parameters including (T), pressure (P), ventilation speed (v), irradiance (S) a...

We consider the energy efficiency of error correction mechanisms on a system consisting of a generalpurpose processor and a wireless interface. Since high error rates are inevitable to the wireless environment, energy efficient error control is an important issue for mobile computing systems. We will show that it is not sufficient to concentrate on the energy efficiency of error control mechani...