Development of a Chirp Stimulus PC-Based Auditory Brainstem Response Audiometer

Hearing losses during infancy and childhood have many negative future effects and impacts on the child life and productivity. The earlier detection of hearing losses, the earlier medical intervention and then the greater benefit of remediation will be. During this research a PC-based audiometer is designed and, currently, the audiometer prototype is in its final development steps. It is based on the auditory brainstem response (ABR) method. Chirp stimuli instead of traditional click stimuli will be used to invoke the ABR signal. The stimulus is designed to synchronize the hair cells movement when it spreads out over the cochlea. In addition to the available hardware utilization (PC and PCI board), the efforts confined to design and implement a hardware prototype and to develop a software package that enables the system to behave as ABR audiometer. By using such a method and chirp stimulus, it is expected to be able to detect hearing impairment (sensorineural) in the first few days of the life and conduct hearing test at low frequency of stimulus. Currently, the intended chirp stimulus has been successfully generated and the implemented module is able to amplify a signal (on the order of ABR signal) to a recordable level. Moreover, a NI-DAQ data acquisition board has been chosen to implement the PC-prototype interface

Development of a Chirp Stimulus PC-Based Auditory Brainstem Response Audiometer

Hearing losses during infancy and childhood have many negative future effects and impacts on the child life and productivity. The earlier detection of hearing losses, the earlier medical intervention and then the greater benefit of remediation will be. During this research a PC-based audiometer is designed and, currently, the audiometer prototype is in its final development steps. It is based on the auditory brainstem response (ABR) method. Chirp stimuli instead of traditional click stimuli will be used to invoke the ABR signal. The stimulus is designed to synchronize the hair cells movement when it spreads out over the cochlea. In addition to the available hardware utilization (PC and PCI board), the efforts confined to design and implement a hardware prototype and to develop a software package that enables the system to behave as ABR audiometer. By using such a method and chirp stimulus, it is expected to be able to detect hearing impairment (sensorineural) in the first few days of the life and conduct hearing test at low frequency of stimulus. Currently, the intended chirp stimulus has been successfully generated and the implemented module is able to amplify a signal (on the order of ABR signal) to a recordable level. Moreover, a NI-DAQ data acquisition board has been chosen to implement the PC-prototype interface

Detektor Ml Untuk Komunikasi Antena Jamak

Simple ML Detector for Multiple Antennas Communication System. In order to support providing broadbandwireless communication services against limited and expensive frequency bandwidth, we have to develop a bandwidthefficient system. Therefore, in this paper we propose a closed-loop MIMO (Multiple-Input-Multiple-Output) systemusing ML (Maximum Likelihood) detector to optimize capacity and to increase system performance. What is especiallyexciting about the benefits offered by MIMO is that a high capacity and performance can be attained without additionalfrequency-spectral resource. The grand scenario of this concept is the attained advantages of transformation matriceshaving capability to allocate transmitted signals power suit to the channel. Furthermore, product of these matrices formsparallel singular channels. Due to zero inter-channels correlation, thus we can design ML detector to increase thesystem performance. Finally, computer simulations validates that at 0 dB SNR our system can reach optimal capacityup to 1 bps/Hz and SER up to 0.2 higher than opened-loop MIMO

DETEKTOR ML UNTUK KOMUNIKASI ANTENA JAMAK

Simple ML Detector for Multiple Antennas Communication System. In order to support providing broadbandwireless communication services against limited and expensive frequency bandwidth, we have to develop a bandwidthefficient system. Therefore, in this paper we propose a closed-loop MIMO (Multiple-Input-Multiple-Output) systemusing ML (Maximum Likelihood) detector to optimize capacity and to increase system performance. What is especiallyexciting about the benefits offered by MIMO is that a high capacity and performance can be attained without additionalfrequency-spectral resource. The grand scenario of this concept is the attained advantages of transformation matriceshaving capability to allocate transmitted signals power suit to the channel. Furthermore, product of these matrices formsparallel singular channels. Due to zero inter-channels correlation, thus we can design ML detector to increase thesystem performance. Finally, computer simulations validates that at 0 dB SNR our system can reach optimal capacityup to 1 bps/Hz and SER up to 0.2 higher than opened-loop MIMO.Keywords: fading, MIMO, SVD, M

MODEL SINUSOIDA SECARA SEGMENTAL UNTUK PENGKODEAN SINYAL SUARA

Segmental Sinusoidal Model for Speech Signal Coding. Periodic signal can be decomposed by sinusoidal componentwith Fourier series. With this characteristic, it can be modeled referring by sinusoidal form. By the sinusoidal model,signal can be quantized in order to encode the speech signal at the lower rate. The recent sinusoidal method isimplemented in speech coding. By using this method, a block of the speech signal with 20 ms to 30 ms width is codedbased on Fourier series coefficients. The new method proposed is quantization and reconstruction of speech signal bythe segmental sinusoidal model. A segment is defined as a block of the speech signal from certain peak to consecutivepeak. The length of the segment is variable, instead of the fixed block like the recent sinusoidal method. Coder consistsof the encoder and the decoder. Encoder works to code speech signal at variable rate. Then coded signal will betransmitted to receiver. On the receiver, coded signal will be reconstructed, so that the reconstruction signal has the nearquality compared with the original signal. The experimental results show that the average of segmental SNR is morethan 20 dB.Keywords: peak, period, quantization, segmental, sinusoida

Model Sinusoida Secara Segmental Untuk Pengkodean Sinyal Suara

Segmental Sinusoidal Model for Speech Signal Coding. Periodic signal can be decomposed by sinusoidal componentwith Fourier series. With this characteristic, it can be modeled referring by sinusoidal form. By the sinusoidal model,signal can be quantized in order to encode the speech signal at the lower rate. The recent sinusoidal method isimplemented in speech coding. By using this method, a block of the speech signal with 20 ms to 30 ms width is codedbased on Fourier series coefficients. The new method proposed is quantization and reconstruction of speech signal bythe segmental sinusoidal model. A segment is defined as a block of the speech signal from certain peak to consecutivepeak. The length of the segment is variable, instead of the fixed block like the recent sinusoidal method. Coder consistsof the encoder and the decoder. Encoder works to code speech signal at variable rate. Then coded signal will betransmitted to receiver. On the receiver, coded signal will be reconstructed, so that the reconstruction signal has the nearquality compared with the original signal. The experimental results show that the average of segmental SNR is morethan 20 dB

Concepts for increasing gentamicin release from handmade bone cement beads

Background and purpose Commercial gentamicin-loaded bone cement beads (Septopal) constitute an effective delivery system for local antibiotic therapy. These beads are not available in all parts of the world, and are too expensive for frequent use in others. Thus, orthopedic surgeons worldwide make antibiotic-loaded beads themselves. However, these beads are usually not as effective as the commercial beads because of inadequate release kinetics. Our purpose was to develop a simple, cheap, and effective formulation to prepare gentamicin-loaded beads with release properties and antibacterial efficacy similar to the commercially ones. Methods Acrylic beads were prepared with variable monomer content: 100% (500 μL/g polymer), 75%, and 50% to increase gentamicin release through creation of a less dense polymer matrix. Using the optimal monomer content, different gel-forming polymeric fillers were added to enhance the permeation of fluids into the beads. Polyvinylpyrrolidone (PVP) 17 was selected as a suitable filler; its concentration was varied and the antibiotic release and antibacterial efficacy of these beads were compared with the corresponding properties of the commercial ones. Results Gentamicin release rate and the extent of release from beads prepared with 50% monomer increased when the PVP17 content was increased. Beads with 15 w/w% PVP17 released 87% of their antibiotic content. This is substantially more than the gentamicin release from Septopal beads (59%). Acrylic beads with 15 w/w% PVP17 reduced bacterial growth by up to 93%, which is similar to the antibacterial properties of the commercial ones. Interpretation A simple, cheap, and effective formulation and preparation process has been described for hand-made gentamicin-releasing acrylic beads, with better release kinetics and with antibacterial efficacy similar to that of the commercial ones

Development of a Chirp Stimulus PC-Based Auditory Brainstem Response Audiometer

Hearing losses during infancy and childhood have many negative future effects and impacts on the child life and productivity. The earlier detection of hearing losses, the earlier medical intervention and then the greater benefit of remediation will be. During this research a PC-based audiometer is designed and, currently, the audiometer prototype is in its final development steps. It is based on the auditory brainstem response (ABR) method. Chirp stimuli instead of traditional click stimuli will be used to invoke the ABR signal. The stimulus is designed to synchronize the hair cells movement when it spreads out over the cochlea. In addition to the available hardware utilization (PC and PCI board), the efforts confined to design and implement a hardware prototype and to develop a software package that enables the system to behave as ABR audiometer. By using such a method and chirp stimulus, it is expected to be able to detect hearing impairment (sensorineural) in the first few days of the life and conduct hearing test at low frequency of stimulus. Currently, the intended chirp stimulus has been successfully generated and the implemented module is able to amplify a signal (on the order of ABR signal) to a recordable level. Moreover, a NI-DAQ data acquisition board has been chosen to implement the PC-prototype interface

Simple ML Detector for Multiple Antennas Communication System

In order to support providing broadband&nbsp;wireless communication services against limited and expensive frequency bandwidth, we have to develop a bandwidth&nbsp;efficient system. Therefore, in this paper we propose a closed-loop MIMO (Multiple-Input-Multiple-Output) system&nbsp;using ML (Maximum Likelihood) detector to optimize capacity and to increase system performance. What is especially&nbsp;exciting about the benefits offered by MIMO is that a high capacity and performance can be attained without additional&nbsp;frequency-spectral resource. The grand scenario of this concept is the attained advantages of transformation matrices&nbsp;having capability to allocate transmitted signals power suit to the channel. Furthermore, product of these matrices forms&nbsp;parallel singular channels. Due to zero inter-channels correlation, thus we can design ML detector to increase the&nbsp;system performance. Finally, computer simulations validates that at 0 dB SNR our system can reach optimal capacity&nbsp;up to 1 bps/Hz and SER up to 0.2 higher than opened-loop MIMO.</p