A technique calledin vivomagnetic resonance spectroscopy (MRS) can be performed along with magnetic resonance imaging (MRI) to obtain information about the chemical content of musculoskeletal lesions. This information can be used for several clinical applications, such as improving the accuracy of lesion diagnosis and monitoring the response to cancer therapies. Initial MRS studies of musculoskeletal tumors show promising results, and the technique has been incorporating into the MRI routine protocols. This article introduces1H MRS of the musculoskeletal tumors, reviews the literature, discusses current methods and technical issues, and describes applications for treatment monitoring and lesion diagnosis.
An error-compensated pulse width modulator (ECPWM) is proposed to improve the baseband harmonic performance and the switching loss of voltage source inverters (VSIs). Selecting between harmonic distortion and switching loss is a design tradeoff in the conventional space vector pulse width modulation. In this work, an accumulated difference in produced and desired phase voltages is considered to adjust the reference signal. This mechanism can compensate for the voltage error in the previous carrier period. With error compensation every half-carrier period, the proposed ECPWM allows one-half reduction in carrier frequency without scarifying baseband harmonic distortion. The proposed modulator is applied to a three-phase VSI with R-L load and a motor-speed-control system for experiments. The measured efficiency and operating temperature of switches confirm the effectiveness of the proposed scheme.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.