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This paper is about the development of Digital Radio Mondiale (DRM) App. It describes overall technology and development motivation that may enable us to overcome the limitation of 1:1 Bluetooth technology. It introduces the DRM compression and modulation, background technology of DRM transmitter and receiver, requirements for DRM signal creation, DRM App configuration, additional tools used for field test, the field test results, and future application of DRM.

A tiny microphone inside the ear canal had been used for capturing the voice that was transferred through the oral and nasal cavities from the vocal code of the speaker. We designed a digital filter optimized for enhancing the transformed voice signal due to the inner facial cavities.

This study identified problems of the existing ecosystem-based fisheries assessment approach, and suggested new methods for scoring risk and for the estimation of fishery risk index. First, risk scores of zero to two for target and limit reference points for each indicator were replaced by those of zero to three, and the risk scores were calculated from new formulae which were developed in this study. Second, a new method for estimating fishery risk index (FRI) was developed in this study, considering the level of indicators. New method was applied to the Korean large purse seine fishery, large pair trawl fishery and drag net fishery. More precise and detailed risk scores were obtained from the new method, which can explain the risks by the wider range of both risk levels for `better than target` and `beyond limit`. The new method for estimating FRI could avoid the basic problem related with duplicated computations of fishery-level indicators, which improved the estimated FRI to be more accurate. Also, a method for estimating variance of FRI using the bootstrap was proposed in this study.

Hearing loss affects hearing impairment at diversely different frequencies, so it is crucial that a good hearing aid should have high frequency resolution. We have developed a 64 channel hearing aid which provides precise control of 125Hz resolution over 8000Hz frequency spectrum with non-linear compression. Probabilistic noise reduction algorithm and feedback cancellation based on frequency domain analysis were developed, which enhances speech clarity while minimizing undesirable ambient noises. The hearing aid can also be controlled and calibrated wirelessly via Bluetooth.

We conducted experiments to compare the catch rate of bigeye tuna and yellowfin tuna between circle hooks and straight shank hook in the Korean tuna longline fishery at the eastern and central Pacific Ocean from 2005 to 2007. We analyzed difference of fork length, survival and hooking location between a circle hook and a straight shank hook for both tunas, respectively. There was no difference in the mean fork length size of yellowfin tuna caught on the two type of hook but bigeye tuna was significant. In case of survival, there was no difference between two hook type, but the difference of hooking location was significant for both species. We also analyzed to find determinants of both tunas catch rate using generalized linear models (GLMs) which were used latitude, longitude, year, month, depth, hook type, bait type and so on as independent variables. Spatial factors, latitude and longitude, and temporal factors, year and month, affected catch rate of bigeye tuna and yellowfin tuna. And also, depth such as a marine environment factor was influenced on catch rate.

The plasticization and/or filler effects of sodium salts of hexanoate (Na6), adipate (Na6Na), dodecanedioate (Na12Na), and dodecylbenzenesulfonate (Na12) on the dynamic mechanical properties of styrene-based ionomers were investigated. When a small amount of Na6, having one carboxylate ionic group at one end of alkyl chain, was added to a styrene-methacrylate ionomer, the salt acted as a very effective plasticizer for the ionomer cluster regions. With increasing salt contents, however, the salts became phase-separated and formed bilayer crystalline domains that acted as filler. In the case of the Na12Na and Na6Na salts, containing two carboxylate ionic groups, one at each end of alkyl chain, they formed phase-separated domains, acting as filler, in the methacrylate ionomers. Na12, possessing one sulfonate ionic group at only one end of a long alkyl chain, acted as a plasticizer in a sulfonated polystyrene ionomer. However, an excess amount of Na12 salt also formed phase-separated domains. It was also found that Na12 showed a filler effect only at much higher salt contents in comparison with Na6.

The most recent trend on digital hearing aid is to increase the ratio of signal to noise by directivity or to develop noise reduction algorithm inside DSP IC chip. This paper designed, fabricated and tested a digital hearing aid directivity testing device in which a micro-mouse-like the stepping motor with a speaker rotates around an examinant. Both ears of the examinant were fixed with ITE hearing aids in order to respond to receiving sound. The experimental results were compared with those of a boundary element method program for verification. The diameter of the directivity testing device was 2 m and the micro-mouse was precisely controlled by PICBASIC micro processor.

This paper describes the application of the coupled FE-BEM (finite element-boundary element method) for the numerical harmonic analysis of the linear dynamic behaviour of a magnetostrictive Terfenol-D rod in water. The magnetostrictive rod is three-dimensionally modeled to transduce applied electric current in a helical coil around the rod to mechanical displacement. The steady-state resonance response of the displacement is shown.

Background: The aim of this study was to investigate the effects of needle-pricking therapy on peripheral facial paralysis. Methods: This study included 162 patients with peripheral facial paralysis, 107 of whom were treated with usual care (conventional and alternative treatments) and 55 of whom were additionally treated with needle-pricking therapy on 3 specific extra-meridian acupuncture points known as ‘Samjoong' (Sānchóng in Chinese). We evaluated changes in facial motor functions and sequelae using the Yanagihara and gross House-Brackmann grading systems before and after treatments. Results: Yanagihara score and House-Brackmann grade significantly improved after treatments in both groups. However, the needle-pricking therapy group showed greater improvements in Yanagihara score and House-Brackmann grade than the usual care group. Conclusion: Our results suggest that Samjoong needle-pricking therapy could be applied as an adjunct therapy to usual care for patients with peripheral facial paralysis.

The Log Amplifier described in this paper is designed for hearing aids (HA) application. It works on a low single-supply voltage (1.3V). The input signal varies between 0.01mV and 100mV. To give enough compensation to the hearing impairment, the amplifier provides a very large gain. The output swing is limited because of the low supply voltage and the large gain. Therefore, the logarithmic amplifier introduced into the design of HA to compress input signal so that the output distortion can be avoid. Another factor we use it here is that the amplifier has enough sensitivity and gain to deal with the compressed input signal without getting extra distortion coursed by the pre-process on input signal. The short channel CMOS devices play an important role in reduction of the supply voltage. DONG-BU ANAM 0.18 μm process is selected.

The noise reduction of the ITE (in‐the‐ear) hearing aid (ha) can be achieved by an array of microphones. Each of the right and the left ears is assumed to be fixed with two HA microphones. This two HA microphone array produces particular patterns of directivity by some time delay between two microphones. The directivity pattern geometrically increases the S/N ratio. The boundary element method (BEM) was used for the three dimensional simulation of the HA directivity pattern with the two pairs microphone arrays. This numerical analysis may then be applied for the calculation of the time delay parameter of the digital hearing aid DSP chip. The separation between two microphones was fixed to 10 mm. The time delay between the two microphones was changed to produce the most narrow directivity pattern in the forefront of the head. The variation of the time delay was examined in accordance with input frequencies.

This paper shows one and two dimensional active linear modeling of cochlear biomechanics using Hspice. The cochlear biomechanical modeling is based on the deductive approach of others but is processed using Hspice which is the most popular analog electric circuit simulator among electrical and electronic engineers. Because Hspice is so generally used for active filter design, the shortage of the present cochlear model may be supplemented with analog active filters added to the present model. This extra filtering may be arbitrary so as to be called second filters. The advantage of the Hspice modeling is that the cochlear biomechanics may be implemented into an analog IC chip. This paper explains in detail how to transform the physical cochlear biomechanics to the electrical circuit model and how to represent the circuit in Hspice code. The comparison between one and two dimensional models is figured.

This study evaluated the effects of electroacupuncture (EA) on endothelial function and endothelial progenitor cells (EPC) in patients with cerebral infarction. In a randomized, placebo-controlled, crossover study, 20 patients with cerebral infarction were randomized into two treatment groups: EA or placebo. Before and after each intervention, pulse amplitude tonometry (PAT) was used to assess endothelial function and peripheral blood was analyzed for the number of EPCs. Circulating EPCs were quantified by flow cytometry as CD45(low) CD34(+) KDR2(+) cells. Plasma vascular endothelial growth factor (VEGF) and interleukin (IL)-10 levels were measured. Seven days later, crossover was performed on each group, with each group receiving the other treatment using the same protocol. The PAT hyperemia ratio ranged from 1.57 ± 0.41 to 2.04 ± 0.51 after EA, representing a significant improvement (P = 0.002); however, there was no improvement in the placebo group (P = 0.48). Circulating EPCs, as measured by flow cytometry, increased to 110.6 ± 74.3/100 μL in the EA group (P = 0.001) but did not change in the placebo group (45.9 ± 35.3/100 μL, P = 0.08). The increases in the number of EPCs and the PAT ratio after treatment were correlated (r = 0.78, P < 0.001). Plasma VEGF levels increased with EA compared to baseline (261.2 ± 34.0 vs 334.9 ± 80.5 pg/mL, P = 0.003). The number of circulating EPCs was positively correlated with plasma levels of VEGF (r = 0.50, P = 0.02). In conclusion, EA induced improvement of EPC levels and the PAT ratio in patients with cerebral infarction.