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Yuri Kwon,1 Sang Hoon Park,1 Ji-Won Kim,1 Yeji Ho,1 Hyeong-Min Jeon,1 Min-Jung Bang,1 Gu-In Jung,1 Seon-Min Lee,3 Gwang-Moon Eom,1,2 Seong-Beom Koh,3 Jeong-Whan Lee,1,2 Heung Seok Jeon41Biomedical Engineering, 2Research Institute of Biomedical Engineering, Konkuk University, Chungju, Korea; 3Department of Neurology, Korea University College of Medicine, Seoul, Korea; 4Department of Computer Engineering, Konkuk University, Chungju, KoreaPurpose: Freezing of gait (FOG), increasing the fall risk and limiting the quality of life, is common at the advanced stage of Parkinson’s disease, typically in old ages. A simple and unobtrusive FOG detection system with a small calculation load would make a fast presentation of on-demand cueing possible. The purpose of this study was to find a practical FOG detection system.Patients and methods: A sole-mounted sensor system was developed for an unobtrusive measurement of acceleration during gait. Twenty patients with Parkinson’s disease participated in this study. A simple and fast time-domain method for the FOG detection was suggested and compared with the conventional frequency-domain method. The parameters used in the FOG detection were optimized for each patient.Results: The calculation load was 1,154 times less in the time-domain method than the conventional method, and the FOG detection performance was comparable between the two domains (P=0.79) and depended on the window length (P<0.01) and dimension of sensor information (P=0.03). Conclusion: A minimally constraining sole-mounted sensor system was developed, and the suggested time-domain method showed comparable FOG detection performance to that of the conventional frequency-domain method. Three-dimensional sensor information and 3–4-second window length were desirable. The suggested system is expected to have more practical clinical applications.Keywords: Parkinson’s disease, freezing of gait, acceleration, detection system, ti

Computational experiments were run using an optimization criterion based on independently motivated definitions of perceptual contrast, articulatory cost and learning cost. The question: If stop+vowel inventories are seen as adaptations to perceptual, articulatory and developmental constraints what would they be like? Simulations successfully predicted typologically widely observed place preferences and the re-use of place features (‘phonemic coding’) in voiced stop inventories. These results demonstrate the feasibility of user-based accounts of phonological facts and indicate the nature of the constraints that over time might shape the formation of both the formal structure and the intrinsic content of sound patterns. While phonetic factors are commonly invoked to account for substantive aspects of phonology, their explanatory scope is here also extended to a fundamental attribute of its formal organization: the combinatorial re-use of phonetic content., tmh_import_11_12_14. QC 20120104

Computational experiments focused on place of articulation in voiced stops were designed to generate ‘optimal’ inventories of CV syllables from a larger set of ‘possible CV:s’ in the presence of independently and numerically defined articulatory, perceptual and developmental constraints. Across vowel contexts the most salient places were retroflex, palatal and uvular. This was evident from acoustic measurements and perceptual data. Simulation results using the criterion of perceptual contrast alone failed to produce systems with the typologically widely attested set [b] [d] [g], whereas using articulatory cost as the sole criterion produced inventories in which bilabial, dental/alveolar and velar onsets formed the core. Neither perceptual contrast, nor articulatory cost, (nor the two combined), produced a consistent re-use of place features (‘phonemic coding’). Only systems constrained by ‘target learning’ exhibited a strong recombination of place features., tmh_import_11_12_14 QC 20111229

Computational experiments focused on place of articulation in voiced stops were designed to generate ‘optimal’ inventories of CV syllables from a larger set of ‘possible CV:s’ in the presence of independently and numerically defined articulatory, perceptual and developmental constraints. Across vowel contexts the most salient places were retroflex, palatal and uvular. This was evident from acoustic measurements and perceptual data. Simulation results using the criterion of perceptual contrast alone failed to produce systems with the typologically widely attested set [b] [d] [g], whereas using articulatory cost as the sole criterion produced inventories in which bilabial, dental/alveolar and velar onsets formed the core. Neither perceptual contrast, nor articulatory cost, (nor the two combined), produced a consistent re-use of place features (‘phonemic coding’). Only systems constrained by ‘target learning’ exhibited a strong recombination of place features., Giampiero Salvis adress: KTH, Dept of Speech Music and Hearing, SE 10044 StockholmRandy Diehl & Sang-Hoon Park: Dept of Psychology, University of Texas at Austin, Austin, Texas 78712, USA

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004., Includes bibliographical references (p. 113-119)., We report measurements of the temperature and power dependence of the microwave frequency intermodulation distortion (IMD) in high quality pulsed laser deposition (PLD) Yttrium Barium Copper Oxide (YBCO) on LaAlO3 substrate. A low-temperature (T < 30 K) increase in IMD is the observation of an upturn of the nonlinear coefficient of the quadratic field dependence of the penetration depth. This IMD upturn is limited by the nonlinear Meissner effect that has been predicted for d-wave high-T, superconductors. Various amounts of IMD increase are observed for different films with impurity (Ni, Zn and Ca) doping and other defects. The demonstration of the IMD upturn and the nonlinear Meissner effect were possible because the IMD measurement is an extremely sensitive method to detect the penetration depth change at even less than 0.01 nm. IMDs from various samples tend to merge at a single universal value at 0 K regardless of disorder, defects, and impurities due to the node singularity at 0 K. There is a similar converging trend in IMD towards the transition temperature T, due to the quasiparticle thermal excitation and depletion of superelectrons. It is most likely that IMD has both intrinsic and extrinsic contributions., (cont.) The 1/T2 divergence at low T of the IMD was theoretically predicted and confirmed with high quality PLD YBCO on LaA103 substrate from below 30 K. We found that Ni-doped YBCO gave an IMD increase comparable to high quality PLD YBCO. This finding agrees with the evidence that Ni (magnetic impurity) does not destroy superconductivity and preserves d-wave symmetry as shown in scanning tunneling microscope experiments. The off-the-resonance excitation experiment indicates that the response time scale of nonlinearity in IMD generation is not affected by the magnitude of two-tone separation [delta]f = f2 - fl in YBCO on LaA103 substrate. But, at low temperature ([delta] < 20 K) and low output power at fundamental frequency (Pit < -30 dBm), the response time scale slows down IMD generation as the [delta]f increases in YBCO on MgO substrate., by Sang-Hoon Park., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004., Includes bibliographical references (p. 113-119)., We report measurements of the temperature and power dependence of the microwave frequency intermodulation distortion (IMD) in high quality pulsed laser deposition (PLD) Yttrium Barium Copper Oxide (YBCO) on LaAlO3 substrate. A low-temperature (T < 30 K) increase in IMD is the observation of an upturn of the nonlinear coefficient of the quadratic field dependence of the penetration depth. This IMD upturn is limited by the nonlinear Meissner effect that has been predicted for d-wave high-T, superconductors. Various amounts of IMD increase are observed for different films with impurity (Ni, Zn and Ca) doping and other defects. The demonstration of the IMD upturn and the nonlinear Meissner effect were possible because the IMD measurement is an extremely sensitive method to detect the penetration depth change at even less than 0.01 nm. IMDs from various samples tend to merge at a single universal value at 0 K regardless of disorder, defects, and impurities due to the node singularity at 0 K. There is a similar converging trend in IMD towards the transition temperature T, due to the quasiparticle thermal excitation and depletion of superelectrons. It is most likely that IMD has both intrinsic and extrinsic contributions., (cont.) The 1/T2 divergence at low T of the IMD was theoretically predicted and confirmed with high quality PLD YBCO on LaA103 substrate from below 30 K. We found that Ni-doped YBCO gave an IMD increase comparable to high quality PLD YBCO. This finding agrees with the evidence that Ni (magnetic impurity) does not destroy superconductivity and preserves d-wave symmetry as shown in scanning tunneling microscope experiments. The off-the-resonance excitation experiment indicates that the response time scale of nonlinearity in IMD generation is not affected by the magnitude of two-tone separation [delta]f = f2 - fl in YBCO on LaA103 substrate. But, at low temperature ([delta] < 20 K) and low output power at fundamental frequency (Pit < -30 dBm), the response time scale slows down IMD generation as the [delta]f increases in YBCO on MgO substrate., by Sang-Hoon Park., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004., Includes bibliographical references (p. 113-119)., We report measurements of the temperature and power dependence of the microwave frequency intermodulation distortion (IMD) in high quality pulsed laser deposition (PLD) Yttrium Barium Copper Oxide (YBCO) on LaAlO3 substrate. A low-temperature (T < 30 K) increase in IMD is the observation of an upturn of the nonlinear coefficient of the quadratic field dependence of the penetration depth. This IMD upturn is limited by the nonlinear Meissner effect that has been predicted for d-wave high-T, superconductors. Various amounts of IMD increase are observed for different films with impurity (Ni, Zn and Ca) doping and other defects. The demonstration of the IMD upturn and the nonlinear Meissner effect were possible because the IMD measurement is an extremely sensitive method to detect the penetration depth change at even less than 0.01 nm. IMDs from various samples tend to merge at a single universal value at 0 K regardless of disorder, defects, and impurities due to the node singularity at 0 K. There is a similar converging trend in IMD towards the transition temperature T, due to the quasiparticle thermal excitation and depletion of superelectrons. It is most likely that IMD has both intrinsic and extrinsic contributions., (cont.) The 1/T2 divergence at low T of the IMD was theoretically predicted and confirmed with high quality PLD YBCO on LaA103 substrate from below 30 K. We found that Ni-doped YBCO gave an IMD increase comparable to high quality PLD YBCO. This finding agrees with the evidence that Ni (magnetic impurity) does not destroy superconductivity and preserves d-wave symmetry as shown in scanning tunneling microscope experiments. The off-the-resonance excitation experiment indicates that the response time scale of nonlinearity in IMD generation is not affected by the magnitude of two-tone separation [delta]f = f2 - fl in YBCO on LaA103 substrate. But, at low temperature ([delta] < 20 K) and low output power at fundamental frequency (Pit < -30 dBm), the response time scale slows down IMD generation as the [delta]f increases in YBCO on MgO substrate., by Sang-Hoon Park., Ph.D.