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For future mobile phones based on cognitive radio technology, a compact multi-band RF front-end architecture is strongly required and an integrated multi-band RF filter bank is a key component in it. Contour-mode resonators are receiving increased attention for a multi-band filter solution, because its resonant frequency is mainly determined by its size and shape, which are defined by lithography. However, spurious responses including flexural vibration are also excited due to its thin structure. To improve resonator performance and suppress spurious modes, visual observation with a laser probe system is very effective. In this paper, we have prototyped a mechanically-coupled disk-array filter, which consists of a Si disk and 2 disk-type resonators of higher-order wine-glass mode, and observed its vibration modes using a high-frequency laser-Doppler vibrometer (UHF-120, Polytec, Inc.). As a result, it was confirmed that higher order wine-glass mode vibration included a compound displacement, and that its out-of-plane vibration amplitude was much smaller than other flexural spurious modes. The observed vibration modes were compared with FEM (Finite Element Method) simulation results. In addition, it was also confirmed that the fabrication error, e.g. miss-alignment, induced asymmetric vibration.

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A surface acoustic wave (SAW) is perturbed from physical and/or chemical changes of an adjacent medium. If a liquid-phase sensor is realized, a shear horizontal SAW (SH-SAW) must be used. The SH-SAW sensors been investigated since 1987. Measuring objects of the SH-SAW sensor are not only immunoreactions but also liquid properties. Feature of the SH-SAW sensor is simultaneous detection of mechanical and electrical properties of liquid. In this paper, first, theory of the SH-SAW sensor is described. Then experimental results using the SH-SAW sensor on 36YX-LiTaO₃ are introduced. Also, the sensor sensitivities of the SH-SAW sensors which are fabricated on piezoelectric substrates are theoretically compared.

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We have developed a quartz pressure sensor for measuring with high accuracy. This sensor uses a dual tuning fork resonator which has frequency change by stress. Frequency change for full scale (FS) is about 10% on the basis of unloaded frequency. This sensor is good repeatability and hysteresis characteristics which is 0.005% FS and 0.008% FS respectively. In addition, pressure transducer are all fabricated by quartz through the technology of photolithography. Indeed, microprocessor-based measuring system is available with high speed counter timer to measure transducer's frequency and to compensate transducer's temperature characteristics and linearity.

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A cognitive radio system, which is researched to use a limited frequency resource effectively, requires a tunable filter with a wide variable frequency range. A resonator with wide band is required to realize the tunable filter. It was reported that a resonator composed of a Cu-electrode/15°YX-LiNbO₃ had wide bandwidth of 12%. This time, authors attempted to fabricate an one-port resonator composed of a grooved Cu-electrode/4°YX-LiNbO₃. As the result, it had a wider bandwidth of 17% of 1.3 times than that on Cu electrode/4°YX-LiNbO₃. This resonator was applied to a tunable filter, and as the results, the tunable filter having tunable range of 6.8% in center frequency was experimentally realized using a band pass filter type circuit, and those having tunable range of 9 to 12% theoretically using a ladder type circuit.

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A Leaky surface acoustic wave (LSAW) on Al-electrodes/36-48°YX-LiTaO₃ substrates have widely used as filters and duplexers in cell phones because of having a suitable electro-mechanical coupling factor, reflection coefficient and good Q-factor for cell phones. In this paper, a new LSAW structure consisted of upper Al-electrodes stacked on lower grooved Cu-electrodes in the LiTaO₃ is proposed and compared with Al-electrodes (0.1λ)/42°YX-LiTaO₃ which has been considered the best structure ever. As the result, authors have been able to improve characteristics of the LSAW.

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Quasilongitudinal modes in quartz ST cut discovered by Anisimkin gave a new possibility of selecting material for sensing devices. An efficient search method is presented based on analyses previously reported.

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Potassium niobate (KNbO₃; KN) is a well known ferroelectric material with perovskite structure. Recently, this crystal has been given much attention as an environmentally friendly material as well as surface acoustic waves (SAW) and bulk acoustic wave (BAW) devices. It is, however, very difficult to grow KN crystals because KN melts incongruently. In this paper, KN crystal fibers have been successfully grown from stoichiometric melt by micro pulling down (μ-PD) method, and parameters necessary for the reproducible growth of KN fiber have been revealed. Dielectric properties of grown fiber crystal were also measured.

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In this study, to reduce the leaky surface acoustic wave (LSAW) attenuation, a layered structure of air/bulk LiNbO₃(LN) layer/elastically softened LN substrate which can be fabricated by a reverse proton exchange (RPE) process was applied to 10° Y-X LN with a larger coupling factor. First, the LSAW attenuation on a structure of air/bulk LN/modified LN was calculated when all material constants of the buried proton exchange (PE) layer were taken into consideration. It was found that the condition in which the attenuation decreases as compared with the bulk value exists for the free and metallized surfaces. Next, the LSAW propagation properties were measured using IDT pairs with 3.6μm wavelength on 10°Y-X LN with the RPE layer and the buried PE layer. The propagation loss PL for the metallized surface was decreased by carrying out the RPE process from 0.44dB/λ of a virgin wafer to 0.01dB/λ. The decrease in PL for the shorted grating was also observed.

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The dependence of power durability on temperature and input power has been studied in detail by using SAW filter with AlMgCu/Ti/AlMgCu/Ti 4-layered electrodes. In case of SAW filters, acceleration factors of degradation are temperature and input power. These 2 factors are not independent in actual SAW filters, but it is necessary to control the condition to keep the independency of these 2 factors in accelerated deterioration test. As the results of power durability estimation of 4-layered electrodes which had done in consideration of the point above, the activation energy of diffusion showed value of bulk diffusion level in the test using 800MHz band filters, and the dependence of input power was increase in proportion to the frequency of input power. Additionally, we successfully improved power durability of 4-layered electrodes by modifying the layered structure and increasing Mg content in AlMgCu alloy layers. In the former case, the dependency of input power didn't change but the absolute level against input power was improved. On the other hand, the dependency of input power and the absolute level against input power didn't change but the dependence of temperature is increase in the latter case.

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A transducer for a micro ultrasonic scalpel has been fabricated. The micro ultrasonic scalpel can be used with an endoscope for a non-abdominal operation or micro surgery, for example, through a microscope. The ultrasonic transducer was 9.8 mm long and 2.7 mm wide and has stepped horn to amplify vibration velocity; tip of the horn is 0.6 mm wide. The scalpel operated at the resonance frequency in longitudinal mode of 278 kHz. The piezoelectric material was lead zirconate titanate (PZT) that was deposited by the hydrothermal method. The vibration velocity at the tip of the horn in longitudinal direction was 4.0 m/s with 40V_p-p driving voltage in both side electrodes. To demonstrate a beneficial effect of the scalpel, a cutting test that the transducer was stuck into pork fat was carried out.

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Quartz has been widely used for resonators and filters because of its excellent electromechanical characteristics. Quartz has a transition temperature, TC, at 573°C. The electromechanical characteristics of quartz have been well investigated for α-phase (below TC), however the characteristics in β-phase have not been well clarified. We investigated the piezoelectric properties of β-quartz plates from 573°C to about 1,300°C. Clear piezoelectric resonances with high quality factors were observed. By using the large frequency temperature coefficient, β-phase quartz can be applicable to temperature sensors in high temperature region above 600°C. We proposed also an unwired set-up using the β-phase quartz temperature sensor.

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High power piezoelectric characteristics of Mn doped KNbO₃ (KN+MnCO₃ x wt% x=0∼0.8 wt%, KN-Mnx) ceramics were firstly reported in this paper. Mechanical quality factor, Q_m, of KN-Mn x ceramics at small amplitude vibration increased with increasing Mn content and the Q_m of KN-Mn0.8 ceramic reached about 820. The maximum vibration velocity, v_o-p, about 2.3 m/s was obtained for KN-Mn0.8 with Q_m=820. The Q_m at large-amplitude vibration for KN-Mn0.8 and Pb(Zr,Ti)O₃ [PZT]-based ceramics [N6] decreased with increasing the v_o-p. The Q_m of KN-Mn0.8 was smaller than that of N6 at the small-amplitude vibration. However, at the large amplitude vibration, v_o-p>0.6 m/s, the Q_m value of KN-Mn0.8 was larger than that of N6. Therefore, it was clarified that KN-based lead-free piezoelectric ceramics possess superior mechanical stability at large-amplitude vibration. This is very good sign for high power piezoelectric applications.

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Realization of high sensitive biosensors is required. As an acoustic wave based biosensor can detect immunoreactions, it is expected for applying the biosensor. In this paper, a shear horizontal (SH) acoustic wave in layered structures, namely Love wave, is discussed on the basis of numerical calculations. For generating the Love wave, a 36YX-LiTaO₃ is chosen as a piezoelectric substrate. Also, SiO₂, polymer, and gold are chosen as guiding layer materials. First, phase velocity and propagation loss are calculated as a function of layer thickness. Then, an additional mass layer is loaded on the guiding layer for simulating bio-layer deposition. The simulated results indicate that high sensitive biosensor is realized by using gold guiding layer.

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Due to recent environment issues, many research findings on non-lead based materials have been disclosed. The author also reported the possibility of improvements piezoelectric materials by microwave (MW) sintering. We checked relationships between domain size and piezoelectric constant d₃₃ in BaTiO₃ ceramics, and grain boundary and domain properties of ceramics, which are reported herein.

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Two types of transducers for small ultrasound probes were fabricated. Titanium or epoxy resin were used for the backing material of the transducers. The piezoelectric material was lead zirconate titanate (PZT) that was deposited by the hydrothermal method. These transducers were built into a small ultrasound probe and the characteristics were evaluated. As a result, we succeeded in the fabrication of a wideband ultrasound probe with a distance resolution of 16μm, a frequency bandwidth of 69MHz in the range of 39 to 98MHz, and a fractional bandwidth of 86% at the epoxy resin backing probe.

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Because of there excellent features such as small-size, wide bandwidth, and low insertion loss, the ladder-type filters based on surface acoustic wave (SAW) technology have been widely used as radio-frequency (RF) filters in mobile communications. We can make wide bandwidth, and low insertion loss, the ladder-type SAW filters on a Cu-grating/15°LiNbO₃ substrate structure. On the other hand, it is said that wide bandwidth filters is bad temperature characteristic. So this paper discusses dynamic temperature compensation of wideband ladder-type SAW filters. First, we investigate how wide tunability is achievable using variable capacitors parallel- and/or series-connectted to SAW resonators in the filter configuration. Second, we measured the temperature characteristic of resonator. Finally, we simulated temperature compensation of wideband ladder-type SAW filters. As a result, we were able to compensate the change of the characteristic with the ladder-type SAW filter connected variable capacitors.

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A droplet is manipulated by using a surface acoustic wave (SAW). If a sensor is fabricated on a SAW propagating surface, a digital microfluidic system is realized. Our proposed microfluidic system consists of a sensor plate/matching layer/piezoelectric substrate. Droplets are manipulated, mixed and measured on the sensor plate. In this paper, we discuss an acoustic streaming which is caused from longitudinal wave radiation on a micro-laboratory. The acoustic streaming on the three-layer structure was observed in the water tank and compared with it on a 128YX-LiNbO₃. The results indicate that the streaming on the three-layer structure is difference with it on the 128YX-LiNbO₃.

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LiTaO₃ is a key material for surface acoustic wave (SAW) devices, bulk devises, piezoelectric elements, pyroelectric sensors and other applications. However, for almost of their applications the LiTaO₃ single crystal is used. In this paper, authors report the growth of LiTaO₃ films on a metal electrode layer by Chemical Vapor Deposition (CVD) by changing Li source condition. The characteristics of the LiTaO₃ films observed by the X-ray diffraction (XRD) and their polarity dependent on the Li source supply volume. By controlling the Li/Ta ratio, high quality ferroelectric LiTaO₃ films are deposited.

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In this paper, we propose a road traffic control method for reducing traffic congestion with genetic algorithm. In the not too distant future, the system which controls the routes of all vehicles in a certain area must be realized. The system should optimize the routes of all vehicles, however the solution space of this problem is enormous. Therefore we apply the genetic algorithm to this problem, by encoding the route of all vehicles to a fixed length chromosome. To improve the search performance, a new genetic operator called “path shortening” is also designed. The effectiveness of the proposed method is shown by the experiment.

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In this paper, we propose a column generation method for the railway crew scheduling problem with a variety of practical constraints such as lower and upper constraints of one continuous traveling, total working time, admissible number of crews, and meal time constraints. The proposed method consists of the two steps. The first step is to derive a lower bound by the column generation and the second step is to generate a feasible solution by a heuristic method. In the proposed method, a label setting algorithm is developed to solve the pricing problem efficiently to reduce computational time. A new dominance condition is developed to eliminate unnecessary states in the label setting algorithm. A heuristic algorithm is also proposed to reduce the generation of the infeasible solutions violating the constraint on the number of the allocated crews. The effectiveness of the proposed method is evaluated by using a real railway data.

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Ultrasonic motors (USMs) intrinsically have a dead-zone property which is sensitive to load changes. This paper proposes a fictitious reference iterative tuning (FRIT) method for systems with a dead-zone property such as USMs. The standard FRIT method is basically developed for linear systems and may not give a satisfactory control performance for noninvertible nonlinear systems including USMs. In contrast, the proposed FRIT method can achieve such a performance by introducing a right inverse of a dead-zone function as a dead-zone compensator. In the optimization process of FRIT, the so-called covariance matrix adaptation evolution strategy (CMA-ES) is used for simultaneously searching a dead-zone parameter as well as controller parameters. CMA-ES is a kind of stochastic multi-point search techniques and is effective for nondifferentiable and nonconvex optimization problems. Experimental results for a USM are given to show the effectiveness of the proposed method.

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In general, the adaptive system using the structure in which an adaptive filter is placed before the unknown system to estimate the inverse transfer function of the unknown system is called pre-inverse adaptive system. The equalizing type adaptive system that the weights of the adaptive transversal filter inserted after the unknown system are copied to the transversal filter inserted before the system is the representative example. The problem of this system is that the convergence value has the bias error since the adaptive parameters are updated to the direction where the estimation error including the noise was minimized. In this paper we consider a noise free equalizing type adaptive algorithm and its application to the adaptive control of the motor. The convergence of the control system is guaranteed under the assumption of the uncorrelated property of the noise, disturbance and the command input. Finally, these results of theoretical consideration are verified by computer simulation.

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The focus of study is to review the FIM statistical behavior in each EKF update and determine its potential in providing sufficient information about Robotic Localization and Mapping problem with intermittent measurements. We provide theoretical analysis and prove that the FIM can successfully describe both upper and lower bounds for the state covariance matrix whenever measurement data is not arrived during robot observations. This approach can give a better picture on how information are processed in EKF when measurement data is partially unavailable. Some simulation evaluations are also included to verify our results and consistently demonstrate the expected outcome.

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The several papers reported that the errors in land cover classification have been generated around the edge of categories especially. The mixed pixel that includes the multiple categories is one of the error factors. All remotely sensed images include the mixed pixel, particularly the influence of the mixed pixels in the middle- or low-resolution images is more serious.
In this paper the method using the nonlinear mixed pixel model and the filtering of the neighborhood pixels have been proposed. In order to verify the effectiveness of the proposed method, the six simulations have been made; two patterns without the proposed filter are for the linear and for the nonlinear models, and four patterns with the proposed filter are for the proposed nonlinear method.
The results of the simulations have been quantitatively evaluated by calculating the correlation coefficients between the simulated results obtained from Landsat-7/ETM+ image and the model answers made by QuickBird-2 images. It was confirmed that the correlation coefficients of the proposed nonlinear model and the proposed filter were improved than that of the other results.

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The applications of composite dispatching rules for multi objective dynamic scheduling have been widely studied in literature. In general, a composite dispatching rule is a combination of several elementary dispatching rules, which is designed to optimize multiple objectives of interest under a certain scheduling environment. The relative importance of elementary dispatching rules is modeled by weight factors. A critical issue for implementation of composite dispatching rule is that the inappropriate weight values may result in poor performance. This paper presents an offline scheduling knowledge acquisition method based on reinforcement learning using simulation technique. The scheduling knowledge is applied to adjust the appropriate weight values of elementary dispatching rules in composite manner with respect to work in process fluctuation of machines during online scheduling. Implementation of the proposed method in a two objectives dynamic job shop scheduling problem is demonstrated and the results are satisfactory.

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A paper filtering system that supports the effective collection of related journal papers is becoming important as the technological progress has been rapid. However, previous systems realized insufficient filtering effectiveness, because of lack of available information in abstract part of journal papers that is available to the public. In this paper, we propose a paper filtering method using the multiple information such as structure, co-author, subject category, terminology, and terms in patent document.
By the evaluation for 15 examinees using 4,875 journal papers, it became clear that for all examinees the effectiveness of proposed method exceeds the conventional method, when the all information above are used, which became closer to practical use.

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There is a stride value predictor as a technology that eases the data dependency that is the factor to restrict the program parallelism. This mechanism predicts the values that the instruction generates by using Value History Table (VHT). There is a problem of confliction of VHT as a factor to limit the predictive performance. In order to reduce confliction of VHT, we focus on predictability to propose two schemes. One is to update the only predictable instructions to VHT, the other is to suppress the replace frequency of VHT. The evaluation results show that improving the predictive performance without increasing the number of entries of VHT or decreasing the number of VHT entries by small predictive performance loss becomes possible by the addition of small-scale dedicated table.

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The event-related potential (ERP) was measured when subjectively judging the appearance of bottles as an example of food appearance by four-grade scale with the opinion “more favorite”, “favorite”, “like”, and “not like”. In result, the P300 area became larger when the subjects judged as “more favorite”.

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We propose a novel interpolation method which is a modified the Bi-linear interpolation. The Bi-linear interpolation is computationally efficient, but it often generates jaggy-noise around the edges. We deal with the double expansion in this paper. In the case of the double expansion, the accuracy of the interpolation is improved and jaggy noise is disappeared by improving the interpolation method for the interior point. Here, we propose a novel edge-adaptive interpolation method for the interior point. By the experimental results, the effectiveness of the proposed method is verified from the subjective and objective points of view.

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