An efficient calibration algorithm for an ambulatory audiometric test system is proposed. This system utilizes a personal digital assistant (PDA) device to generate the correct sound pressure level (SPL) from an audio...An efficient calibration algorithm for an ambulatory audiometric test system is proposed. This system utilizes a personal digital assistant (PDA) device to generate the correct sound pressure level (SPL) from an audiometric transducer such as an earphone. The calibrated sound intensities for an audio-logical examination can be obtained in terms of the sound pressure levels of pure-tonal sinusoidal signals in eight-banded frequency ranges (250, 500, 1 000, 2 000, 3 000, 4 000, 6 000 and 8 000 Hz), and with mapping of the input sound pressure levels by the weight coefficients that are tuned by the delta learning rule. With this scheme, the sound intensities, which evoke eight-banded sound pressure levels by 5 dB steps from a minimum of 25 dB to a maximum of 80 dB, can be generated without volume displacement. Consequently, these sound intensities can be utilized to accurately determine the hearing threshold of a subject in the ambulatory audiometric testing environment.展开更多
A precision measurment of inclusive electron scattering cross sections is carried out at Jefferson Lab in the quasi-elastic region for 4 He, 12 C, 56 Fe and 208 Pb targets. The longitudinal （R L ） and transverse （R...A precision measurment of inclusive electron scattering cross sections is carried out at Jefferson Lab in the quasi-elastic region for 4 He, 12 C, 56 Fe and 208 Pb targets. The longitudinal （R L ） and transverse （R T ） response functions of the nucleon need to be extracted precisely in the momentum transfer range 0.55 GeV/c≤ ｜ q ｜ ≤1.0 GeV/c. To achieve the above goal, a NaI （Tl） calorimeter is used to distinguish good electrons from background, including pions and low energy electrons rescattered from the walls of the spectrometer magnets. Due to a large set of kinematics and changes in HV settings, a number of calibrations are performed for the NaI （Tl） detector. Corrections for a few blocks of NaI （Tl） with bad or no signal are applied. The resolution of the NaI （Tl） detector after calibration reached δE/E^（1/2） ≈ 3% at E=1 GeV. The performance of the NaI （Tl） detector is compared with a simulation. The good calibration and background analysis for the NaI（Tl） detector are very important for the reduction of the systematic error of cross sections and the separation of R L and R T .展开更多
基金supported by the grant of the Korean Ministry of Education, Science and Technology (The Regional Core Research Program/Chungbuk BIT Research-Oriented University Consortium)
文摘An efficient calibration algorithm for an ambulatory audiometric test system is proposed. This system utilizes a personal digital assistant (PDA) device to generate the correct sound pressure level (SPL) from an audiometric transducer such as an earphone. The calibrated sound intensities for an audio-logical examination can be obtained in terms of the sound pressure levels of pure-tonal sinusoidal signals in eight-banded frequency ranges (250, 500, 1 000, 2 000, 3 000, 4 000, 6 000 and 8 000 Hz), and with mapping of the input sound pressure levels by the weight coefficients that are tuned by the delta learning rule. With this scheme, the sound intensities, which evoke eight-banded sound pressure levels by 5 dB steps from a minimum of 25 dB to a maximum of 80 dB, can be generated without volume displacement. Consequently, these sound intensities can be utilized to accurately determine the hearing threshold of a subject in the ambulatory audiometric testing environment.
基金Supported by National Natural Science Foundation of China (10605022,10875053)US Department of Energy (DE-AC05-84ER-40150) under which Jefferson Science Associates operates the Thomas Jefferson National Accelerator Facility
文摘A precision measurment of inclusive electron scattering cross sections is carried out at Jefferson Lab in the quasi-elastic region for 4 He, 12 C, 56 Fe and 208 Pb targets. The longitudinal （R L ） and transverse （R T ） response functions of the nucleon need to be extracted precisely in the momentum transfer range 0.55 GeV/c≤ ｜ q ｜ ≤1.0 GeV/c. To achieve the above goal, a NaI （Tl） calorimeter is used to distinguish good electrons from background, including pions and low energy electrons rescattered from the walls of the spectrometer magnets. Due to a large set of kinematics and changes in HV settings, a number of calibrations are performed for the NaI （Tl） detector. Corrections for a few blocks of NaI （Tl） with bad or no signal are applied. The resolution of the NaI （Tl） detector after calibration reached δE/E^（1/2） ≈ 3% at E=1 GeV. The performance of the NaI （Tl） detector is compared with a simulation. The good calibration and background analysis for the NaI（Tl） detector are very important for the reduction of the systematic error of cross sections and the separation of R L and R T .
