Measurement of sound pressure sensitivity of high-frequency microphone using multiple harmonics in intense ultrasonic beams

the impact of musical texts on the text recall of young learners of english in isfahan junior high schools

abstract although music possesses some kind of power and using it has been welcome by many students in language classrooms, it seems that they take a non-serious image of the lesson while listening to songs and they may think that it is a matter of fun. the main objective of the present study was to investigate whether learning a foreign language through musical texts (songs) can have an impac...

Low-Frequency Loudspeaker Assessment by Nearfield Sound-Pressure Measurement*

GLOSSARY OF SYMBOLS r distance from pressure sample point to center of piston a radius of circular radiator R_ dc resistance of driver voice coil ao radius of diaphragm, = _/SD/_r E surface area ay radius of circular vent, = 5/Sv/_r SD effective projected surface area of driver diaphragm c velocity of sound in air, = 343 m/s Sv cross-sectional area of vent ein voltage applied to driver input SP...

focus on communication in iranian high school language classes: a study of the role of teaching materials in changing the focus onto communication in language classes

چکیده ارتباط در کلاس به عوامل زیادی از جمله معلمان، دانش آموزان، برنامه های درسی و از همه مهم تر، مواد آموزشی وابسته است. در تدریس ارتباطی زبان که تاکید زیادی بر توانش ارتباطی دارد، کتاب درسی به عنوان عامل موثر بر پویایی کلاس محسوب میگردد که درس ها را از طریق فراهم آوردن متن ارتباط کلاسی و هم چنین نوع تمرین زبانی که دانش آموزان در طول فعالیت های کلاسی به آن مشغول اند، کنترل می کند. این حقیقت ک...

A High Polarization Target for Intense Beams

Sub-shot-noise phase quadrature measurement of intense light beams.

We present a setup for performing sub-shot-noise measurements of the phase quadrature of intense pulsed light without the use of a separate local oscillator. A Mach-Zehnder interferometer with an unbalanced arm length is used to detect the fluctuations of the phase quadrature at a single sideband frequency. With this setup, the nonseparability of a pair of quadrature-entangled beams is demonstr...