bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pulse‐type bursting neuron model using enhancement mode MOSFETs
Authors: Saeki Katsutoshi , Sekine Yoshifumi , Aihara Kazuyuki 
Published: October 2002

AbstractRecently, research has examined the implementation of brain‐like information processing systems by focusing on the information processing ability of the brains of living organisms, modeling the neural network in the brain, and employing integrated circuit technologies for engineering applications. Since information is transmitted by pulses in the brain, a pulse‐type model that models the actual unmodified pulse waveforms is effective because the basic nature of neurons is considered. Recently, attention has centered on research of models that obtain burst firing that repeats firing and not firing. This research involves both physiological experiments and theoretical models. However, there were few practical models that could be integrated. Previously, the authors proposed a pulse‐type bursting neuron model constructed from depletion‐mode MOSFETs, resistors, and capacitors that could exhibit burst firing. In this paper, we propose a new pulse‐type bursting neuron model corresponding to a modified Bonhoeffer‐van der Pol (BVP) model. This model is constructed only from enhancement‐mode MOSFETs and capacitors that can be applied to the standard method using the CMOS process. First, we explain the theory of our previously proposed pulse‐type bursting neuron model. Then we build a voltage‐controlled negative resistance circuit using the enhancement‐mode MOSFET examined here, and clearly show the changes in the characteristics of the negative resistance by using the voltage of the control terminal as the parameter. We demonstrate that the pulse‐type bursting neuron model corresponding to the modified BVP model can be integrated and implemented. This model can be applied to the standard method using the CMOS process by using this negative resistance circuit, and only enhancement‐mode MOSFETs and capacitors. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(11): 1–7, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10054
Acoustic modeling for speech recognition based on a generalized Laplacian mixture distribution
Authors: Nakamura Atsushi 
Published: October 2002

AbstractIn acoustic modeling for speech recognition, the Gaussian distribution or the Gaussian mixture distribution is widely used. The general reason for preference of the Gaussian distribution in the parametric modeling of an unknown ensemble is the central limit theorem. The Gaussian distribution has many properties that are theoretically clear. For the particular problem, however, in which the time series of an acoustic feature is to be modeled on the basis of a limited number of training samples for speech recognition, there is no guarantee that the method based on the Gaussian distribution is always optimal. Consequently, this paper proposes an acoustic modeling approach based on the generalized Laplacian distribution, which can represent a wider range of distribution shapes, including the Laplacian and Gaussian distributions. The formulation of the generalized Laplacian distribution and the method of estimation of the distribution parameters are described. The acoustic model with the generalized Laplacian mixture output distribution is constructed by retraining of the hidden Markov model with the Gaussian mixture output distribution. It is shown by a continuous speech recognition experiment using natural uttered speech that the recognition performance is improved compared to recognition based on the Gaussian mixture distribution. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(11): 32–42, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10093
A method for detecting fundamental pitch periods of speech utterances using continuity properties of spectral envelopes in the time domain
Authors: Yanagisawa Koichi , Tanaka Kyoko , Yamaura Itsuo 
Published: October 2002

AbstractIn this article, we use the continuity properties of the speech spectral envelope in the time domain to distinguish the true fundamental pitch period (frequency) of an utterance from several candidates for the fundamental period previously obtained by the autocorrelation method, which is itself robust against noise. Because the correlation function is not necessarily a global maximum at the fundamental period due to effects of noise and the like, in using the autocorrelation method, any period at which the correlation function has a maximum must be regarded as a candidate for the fundamental period. In order to distinguish the real period from among these candidates, discrete spectra are generated from the log spectrum by sampling the latter at frequencies that correspond to integer multiples of each candidate fundamental frequency. Each of these discrete spectra then becomes a spectrum envelope candidate. The fundamental period is then determined by using the continuity properties of the shape of the true spectrum envelope in the time domain as criteria. Experimental results indicate that by using this method it is possible to reduce the detection error at a signal‐to‐noise ratio of 0 dB by 5 to 10% compared to ordinary cepstrum and autocorrelation methods under conditions where several kinds of day‐to‐day environmental noise are present. Experiments also confirm that it provides excellent sensitivity in the presence of weak periodic (fan‐motor) noise compared with the autocorrelation method. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(11): 43–55, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10094
A system employing high‐quality speech compression technology to produce voice on demand for visually handicapped persons
Authors: Kaneko Takao , Ohmuro Hitoshi , Mano Kazunori 
Published: October 2002

AbstractWe have developed a voice‐on‐demand system in which a voice reading the latest information such as newspapers and public bulletins or regional information is information‐compressed by a voice coding technique and stored on the disks of a PC server, and then distributed to receivers at the homes of visually handicapped persons via ISDN networks. In the compression of read speech, the low‐rate speech coding technique DualSpeech is developed and introduced. The information content is reduced to about 1/18 with almost no degradation of the quality of the read speech, so that it can be distributed at high speed. Moreover, the one‐megabyte memory embedded in the receiver can store about 60 minutes of the read speech compactly and the stored information content can be retrieved instantly by an index retrieval function. With these merits, the time required in distribution and communication charges are reduced, and a voice‐on‐demand service is realized which has the appeal of allowing repeated listening at any time to information which the visually handicapped persons would like to acquire. Evaluation of the performance of this voice‐on‐demand system indicates that the read speech data can be received in a short time, about 1/8 of the regeneration time, and regenerated speech can be obtained with a high quality equal to that of the personal handy‐phone system (PHS). Moreover, we have performed service experiments using the voice‐on‐demand system employing speech compression for about 50 visually handicapped persons. The following desirable features have become clear from the questionnaire results: enrichment of close‐at‐home information which the visually handicapped persons can select by themselves, increase of the update frequency of the information content, and further enhancement of the operability of the receiver. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(11): 56–70, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10095
A method of preparing thin‐film micro‐PTC thermistors based on BaTiO3 using YAG‐laser irradiation
Authors: Sato Yuichi , Kawamura Toshiaki , Sato Susumu 
Published: October 2002

AbstractA technique is proposed for obtaining thin‐film positive temperature coefficient (PTC) microthermistors made of BaTiO3‐based material. In this technique, stacked layers of Ti and BaO thin films are irradiated in air by a YAG laser beam, which creates BaTiO3 semiconductor microregions with PTC characteristics. The experiments indicate that by suitably choosing the optical power of the laser beam and its scanning rate over the stacked layers, it is possible, and in fact easy, to control the resistance of the resulting BaTiO3 semiconductor microregions. We found that the resistance of the BaTiO3 semiconductor material created in this way must be sufficiently low in order for the material to exhibit PTC characteristics. In this case, the material becomes a thermistor, that is, its resistance increases rapidly with increasing temperature. As the temperature increases, the resistance suddenly begins to increase starting at a certain threshold temperature. In an attempt to control this threshold temperature, we modified the technique described in this research by replacing some of the Ti sites with Zr. This modified technique led us to conclude that, just as in bulk BaTiO3, such control was indeed possible. When our technique is used, high‐temperature heating of the entire substrate is not necessary, either during the deposition of the thin film or after its deposition. In this way we confirm that it is possible to create compound device modules by fabricating multiple thin‐film microdevices on a single substrate, including PTC microthermistors. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(11): 25–31, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.1113
A decade of military support for the Coastal America partnership
Authors: Schlossnagle George , Tippie Virginia K. 
Published: October 2002

AbstractIn 1992 the Army, Navy, and Air Force, and the Department of Transportation signed a Memorandum of Understanding
(MOU) with four other federal departments and the Council on Environmental Quality (CEQ). This
memorandum established the Coastal America Partnership and its principles for action; to protect, restore, and
maintain the nation's coastal living resources. Thus, the military, including the Coast Guard, have worked
with Coastal America Partners in many activities ranging from restoration and protection of coastal ecosystems such
as marshlands and reefs to the removal of obsolete and unsafe dams to restore fish migration paths. Within the
Coastal America partnership, the military partners have worked with communities, states, and other federal partners
to enhance the environment. © 2002 Wiley Periodicals, Inc.
Cost, operational readiness, and environmental benefits for the reutilization of used hydraulic oil
Authors: Mowery Ralph B. , Teefy Dennis A. , Werner Neal C. 
Published: October 2002

AbstractThe U.S. Army, in cooperation with industry, recently developed and demonstrated a methodology for returning
used hydraulic fluid to vehicle service. The effort was conducted in three phases: First, a laboratory
investigation to determine the viability of restoring used fluid to military specification performance. Second,
a field investigation designed to identify commercially available equipment that could successfully process the
used fluid and also demonstrate the performance of the restored fluid in military vehicles. Third, the Army
entered into Cooperative Research and Development Agreements (CRADAs) with commercial companies that
manufacture the certified hydraulic oil recyclers to test on‐line diagnostics aimed at automating and
optimizing the process. Under the aegis of the aforementioned CRADA, industry developed technology that
automates the process of restoring used hydraulic fluid to military specification performance. Testing and
demonstration results indicate that the process of restoring used hydraulic fluid can be automated to require
less labor and eliminate possible incomplete restoration. This paper briefly explains the recommended process
developed by the Fuels and Lubricants Team as presented in the “User's Guide For Recycling Military
Hydraulic Fluid.” Recent military implementation of hydraulic oil restoration programs, studies, and
field demonstrations within the U.S. Army, Navy, and Air Force are discussed.The on‐site reutilization of used hydraulic fluid with a certified hydraulic oil recycler can have a
significant impact on meeting pollution prevention goals. The benefits include reduced fluid disposal costs,
reduced procurement costs for new fluid, increased operational readiness, increased durability of systems, and
an uncomplicated avenue for conservation of natural resources. Procedures and certifications for this program
are now in place. The implementation of a hydraulic oil recycling program will save millions of dollars per
year for each of the U.S. military services, as well as contribute to operational readiness. © 2002 Wiley
Periodicals, Inc.
Evaluation of high levels of lead in select Department of Defense plastic playground equipment
Authors: Belfit Victoria F. , Nix Bryan J. , Graham Stephan C. 
Published: October 2002

AbstractThis paper provides information on evaluations of childhood lead exposures associated with Department of
Defense (DOD) elementary schools and Army family housing and child development center (CDC)
plastic playground equipment (PE). DOD has fully evaluated the elementary school plastic PE. Playground
equipment similar to DOD school PE exists in military housing and CDCs throughout Europe. Surveys of plastic PE
found six brands that contained high levels of lead. Absent federal standards for lead in dust on plastic PE, DOD
applied a standard of 100 μg/ft_, based on the EPA / HUD clearance level for lead in dust on
residential floors. Eleven percent of components tested in 73 schools exceeded the 100
μg/ft_standard. In 2001, EPA lowered this standard to 40 μg/ft_. There is still
equipment present with lead levels between 40 μg/ft_and 100 μg/ft_.
Lead‐containing PE has also been identified within the United States. Army offices are working with Federal
agencies and the services to determine the location of lead‐containing PE within the United States and to
establish consensus standards. © 2002 Wiley Periodicals, Inc.
Patched grid and adaptive mesh refinement strategies for the calculation of the transport of vortices
Authors: Benkenida A. , Bohbot J. , Jouhaud J. C. 
Published: October 2002

AbstractThis paper presents two techniques allowing local grid refinement to calculate the transport of vortices. one is the patched grid (PG) method which allows non‐coincident interfaces between blocks. Treatment of the non‐coincident interfaces is given in detail. The second one is the adaptive mesh refinement (AMR) method which has been developed in order to create embedded sub‐grids. The efficiency of these two methods is demonstrated by some validating tests. Then the PG and AMR strategies are applied in the computation of the transport of vortices. We start with a simple vortex flow in a cubic box. Then, the flowfield around a complex aircraft configuration is calculated using the two refinement techniques. Results are compared with a fine, referenced grid calculation. Copyright © 2002 John Wiley & Sons, Ltd.
Injection/suction boundary conditions for fluid–structure interaction simulations in incompressible flow
Authors: Medic G. , Mohammadi B. 
Published: October 2002

AbstractThis paper presents the analysis of injection/suction boundary conditions in the context of the fluid–structure interactions simulation of the incompressible turbulent flow.First, the equations used in the modelling of the fluid and the structure are presented, as well as the numerical methods used in the corresponding solvers. Injection/suction boundary conditions are then presented with details of different implementation alternatives. Arbitrary Lagrangian–Eulerian (ALE) approach was also implemented in order to test the injection/suction boundary conditions.Numerical tests are performed where injection/suction boundary conditions are compared to ALE simulations. These tests include forced movement of the structure and two‐degrees‐of‐freedom structure model simulations. Copyright © 2002 John Wiley & Sons, Ltd.
Feedback control of the Rayleigh–Bénard convection by means of mode reduction
Authors: Park H. M. , Lee W. J. 
Published: October 2002

AbstractAn optimal feedback control is synthesized for the Rayleigh–Bénard convection by means of empirical reduction of modes. The Boussinesq equation is reduced to a minimal set of ordinary differential equations by using the Karhunen–Loève Galerkin procedure. The state feedback control synthesis, that drives the intensity of convection to a preset trajectory by adjusting heat flux at the bottom of the system, is constructed using this low‐dimensional dynamic model by first performing an extended Kalman filter estimate of the velocity and temperature fields and then developing the optimal feedback law by means of the linear regulator theory. The present technique allows for the practical implementation of modern control concepts to the natural convection and is found to yield satisfactory results. Copyright © 2002 John Wiley & Sons, Ltd.
Loss of G2/M arrest correlates with radiosensitization in two human sarcoma cell lines with mutant p53
Authors: Bache M. , Pigorsch S. , Dunst J. , Würl P. , Meye A. , Bartel F. , Schmidt H. , Rath F.W. , Taubert H. 
Published: October 2002

AbstractWe have examined the modulation of radiosensitivity by using caffeine in two human sarcoma cell lines both with a p53 mutation (US8‐93 and LMS6‐93). In both cell lines a strong irradiation‐induced G2/M arrest was coupled with a low rate of apoptosis. Incubation with caffeine resulted in a low percentage of S and G2/M cells, associated with an accumulation in G1. With a higher caffeine concentration, we detected a lower clonogenic survival with IC50 at 2 mM. In both cell lines incubation with caffeine completely prevents the irradiation‐induced G2/M arrest. This was connected to radiosensitization, but without direct correlation to an induction of apoptosis. The effect of radiosensitization rose with higher irradiation doses. However, in comparison with LMS6‐93, it was stronger in cell line US8‐93. A higher radiosensitization in US8‐93 correlated with the prevention of strong irradiation‐induced G2/M response and higher initial DNA damage. Results of Western hybridization reveal a p53‐independent mechanism of radiosensitization caused by caffeine. Our findings suggest that modulation in G2/M regulation may affect a common checkpoint for tumor cells with defective p53 function. Furthermore, our results show that the enhancer effect of caffeine is dependent on a strong reduction in the number of G2/M arrested cells and on an inhibition of DNA damage repair after irradiation. © 2001 Wiley‐Liss, Inc.
An investigation of a model of percentage depth dose for irregularly shaped fields
Authors: Hossain Murshed , Xiao Ying , Huq M. Saiful 
Published: October 2002

AbstractA significant component of the total dose delivered to tumor and surrounding tissue during a radiation treatment arises from the scattering of the primary beam. Accounting for this component accurately and efficiently is a necessity. In this study we investigate a method for calculating the phantom‐scatter contributions to the total dose by simple summation of scatter dose from a set of individual triangles that span an irregular field. The calculation of phantom scatter is based on a two‐parameter model, which is applicable to regions where electron equilibrium is established. The two physical parameters are the dose‐averaged linear attenuation coefficient and the beam‐hardening coefficient. The advantage of this model is that it is a natural method when an irregular field is shaped by a multi‐leaf collimator (MLC). Accuracy is not compromised by the triangulation since the irregular field is defined by the straight edges of the MLC leaves. The model predicts the percent depth dose with acceptable accuracy for any arbitrary shape of fields. We report on results for 6‐ and 18‐MV photon beams and for a number of irregularly shaped fields. © 2001 Wiley‐Liss, Inc.
IUdR polymers for combined continuous low‐dose rate and high‐dose rate sensitization of experimental human malignant gliomas
Authors: Yuan Xuan , Dillehay Larry E. , Williams Jerry R. , Williams Jeffery A. 
Published: October 2002

AbstractLocal polymeric delivery enhances IUdR radiosensitization of human malignant gliomas (MG). The combined low‐dose rate (LDR) (0.03 Gy/h) and fractionated high‐dose rate (HDR) treatments result in cures of experimental MGs. To enhance efficacy, we combined polymeric IUdR delivery, LDR, and HDR for treatments of both subcutaneous and intracranial MGs. In vitro: Cells (U251 MG) were trypsinized and replated in triplicate 1 day prior to LDR irradiation in media either without (control) or with 10 μM IUdR. After 72 hr, LDR irradiation cells were acutely irradiated (1.1 Gy/min) with increasing (0, 1.25, 2.5, 5.0, or 10 Gy) single doses. Implantable IUdR polymers [(poly(bis(p‐carboxyphenoxy)‐propane) (PCPP): sebaic acid (PCPP:SA), 20:80] (50% loading; 10 mg) were synthesized. In vivo: For flank vs. intracranial tumors, mice had 6 × 106 subcutaneous vs. 2 × 105 intracranial cells. For intracranial or subcutaneous MGs, mice had intratumoral blank (empty) vs. IUdR polymer treatments. One day after implantation, mice had immediate external LDR (3 cGy/h × 3 days total body irradiation) or HDR (2 Gy BID × 4 days to tumor site) or concurrent treatments. For the in vitro IUdR treatments, LDR resulted in a striking increase in cell‐killing when combined with HDR. For the in vivo LDR treatments of flank tumors, the growth delay was greater for the IUdR vs. blank polymer treatments. For the combined LDR and HDR, the IUdR treatments resulted in a dramatic decrease in tumor volumes. On day 60 the log V/V0 were −1.7 ± 0.22 for combined LDR + HDR + IUdR polymer (P < 0.05 vs. combined LDR + HDR + blank polymer). Survival for the intracranial controls was 22.9 ± 1.2 days. For the blank polymer + LDR vs. blank polymer + LDR + HDR treatments, survival was 25.3 ± 1.7 (P = NS) vs. 48.1 ± 3.5 days (P < 0.05). For IUdR polymer + LDR treatment survival was 27.3 ± 2.3 days (P = NS). The most striking improvement in survival followed the IUdR polymer + LDR + HDR treatment: 66.0 + 6.4 days (P < 0.05 vs. blank polymer + LDR + HDR). The polymeric IUdR delivery plus combined continuous LDR and HDR treatments results in growth delay and improved survival in animals bearing the MG xenografts. This treatment may hold promise for the treatment of human MGs. © 2001 Wiley‐Liss, Inc.