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A power converter is required to be compact, lightweight and low loss, and the various approaches have thus been carried out so far. For a forward converters (FC) used for step-down of medium-capacity, many papers that aims at its miniaturization by coupling the isolation transformers and the output reactors have been reported. Each method of the integrated magnetic components (IMC) shows that the position of the windings and the gaps are different and the total volume becomes smaller than that before coupling. However, it is not clear which method should be adopted to obtain the desired performance and what kind of characteristics it can judge from. Therefore, we classified the FC's IMC from the way of the coupling and investigate the operation of the FC depending on the winding of the IMC in this paper. As results from simulation and experimental analysis, the winding position suitable for the FC, the way of reducing the volume of the magnetic component and suppressing the ripple of the input/output current became clear.

Background: Patients with encephalopathy heralded by a prolonged seizure as the initial symptom often have abnormal subcortical white matter on diffusion-weighted MRI (DWI). Objective: To determine if these patients share other common features. Methods: Patients with encephalopathy heralded by a prolonged seizure and followed by the identification of abnormal subcortical white matter on MRI were collected retrospectively. Their clinical, laboratory, and radiologic data were reviewed. Results: Seventeen patients were identified, ages 10 months to 4 years. All had a prolonged febrile seizure (longer than 1 hour in 12 patients) as their initial symptom. Subsequent seizures, most often in clusters of complex partial seizures, were seen 4 to 6 days after the initial seizure in 16 patients. Outcome ranged from almost normal to severe mental retardation. MRI performed within 2 days of presentation showed no abnormality. Subcortical white matter lesions were observed on DWI between 3 and 9 days in all 17 patients. T2-weighted images showed linear high intensity of subcortical U fibers in 13 patients. The lesions were predominantly frontal or frontoparietal in location with sparing of the perirolandic region. The diffusion abnormality disappeared between days 9 and 25, and cerebral atrophy was detected later than 2 weeks. Three patients having only frontal lesions had relatively good clinical outcome. Conclusions: Although the pathophysiologic mechanism remains unknown, these patients seem to have a distinctive encephalopathy syndrome. MRI is helpful in establishing the diagnosis of this encephalopathy.

This note considers the swinging up of a cart-pendulum system with viscous friction by energy control. An experimental result indicates that a complete swinging up of the pendulum cannot be achieved by the control strategy of Lozano et al. when the effects of the friction are not negligible. It is shown that the performance is improved when a slight modification is introduced to the control algorithm by cancellation of the friction term in the closed-loop equation of the pendulum. The effectiveness of the proposed controller is demonstrated experimentally.

The design and performance of a LiNbO/sub 3/ optical modulator and switch, which employ superconducting circuits, have been studied. Based on a novel design method of the booster circuit using superconducting coplanar waveguide transmission lines, we designed a voltage amplifier with center frequency of 10 GHz, bandwidth of 5 MHz, and the voltage gain of 33 dB using an electromagnetic wave simulator. We also designed a high speed optical switch combining optical directional coupler and Mach-Zehnder interferometer. A preliminary experiment with YBCO electrode on MgO substrate flip-chip-bonded on LiNbO/sub 3/ optical waveguide has been made.

The effect of the chain length distribution on the phase behavior, the structure of liquid crystals, and physicochemical properties was investigated in water/ polyglycerol fatty acid ester. Polyglycerol fatty acid esters with sharply distributed polyglycerol (10G*0.7L) and with broadly distributed polyglycerol (10G0.7L) were used. Unreacted polyglycerol in both surfactants was removed. 10G*0.7L forms hexagonal liquid crystals at a higher concentration than 10G0.7L. The effective cross-sectional area of the lipophilic parts in the hexagonal phase of 10G0.7L is smaller than that of 10G*0.7L owing to the difference in the chain length distribution. Evidently, 10G0.7L molecules are tightly packed in aggregates; therefore, 10G0.7L decreased the surface tension more strongly and promoted emulsification.

We have applied the first-principles molecular dynamics simulation based on the linearized-augmented-plane-wave (LAPW) method to Se8 and Se8 + clusters. The equilibrium structures are obtained for Se8 and Se8 + clusters: for the ionized cluster Se8 +, we have found a remarkable structural change from that for the neutral cluster, which reflects the strong electron-lattice coupling in the cluster. The vibrational properties for Se8 are also presented.

The equiliblium structures of small selenium clusters are obtained via first-principle molecular dynamics calculations based on the linearized-augmented-plane-wave (LAPW) method. Resulting equiliblium structures show a good agreement with experimental data and other firstprinciple calculations.

The equilibrium structures of small selenium clusters are obtained via first-principle molecular dynamics calculations based on the linearized-augmented-plane-wave (LAPW) method. Resulting equilibrium structures show a good agreement with experimental data and other first-principle calculations.

The paper deals with the stability of zeros of sampled-systems that are composed of a fractional-order hold, a continuous-time plant and a sampler in cascade. The stability conditions of the limiting zeros for sufficiently small or large sampling periods are derived. It is also shown that one can determine the range of the sampling period for stable zeros of the sampled system by calculating an analytical form of a criterion under a lowpass assumption on a continuous plant.

Some liquid metals can be regarded as a binary mixture of ions and electrons interacting via binary interparticle interactions with each other. It is shown exactly on the basis of the density-functional method that a liquid metal can be taken as a quasi one-component system only via a pairwise interatomic interaction (without a many-body force) to obtain the radial distribution function, provided that a liquid metal can be thought of as an ion-electron mixture with binary interactions.

By regarding a liquid metal as a mixture of electrons and nuclei, the quantal hypernetted-chain (QHNC) equations have been derived from the density-functional theory. These integral equations for the ion-ion and electron-ion radial distribution functions (RDFS) can give the electron distribution function of a neutral pseudoatom rho (r) and the effective interionic potential upsilon eff(r) self-consistently, using the atomic number ZA as the only input data. The authors apply these equations to liquid potassium at 338 K. The ion-ion RDF gII(r) and structure factor SII(Q) obtained from QHNC agree with the experimental results from X-ray diffraction very well. The electron-ion RDF is calculated to be self-consistent with the effective interionic potential giving the ion-ion RDF in the QHNC framework. For comparison, the results of the pseudopotential method with Ashcroft's model potential (core radius rC=1.225 AA) are also shown; this method can give the same ionic structures, but it provides slightly different electron distributions from the QHNC results. These differences between the QHNC and pseudopotential methods in the electron distribution are not observed in liquid sodium, and are attributed to the fact that the Ashcroft potential omega bAC(r) cannot appropriately approximate the direct correlation function CeI(r), which plays the role of a non-linear pseudopotential.

On the basis of the density-functional theory with the use of the hypernetted-chain approximation, a set of integral equations for the ion-ion and electron-ion radial distribution functions (RDFs) have been derived for a liquid metal as a nucleus-electron mixture; its liquid and electronic structures can be determined from the atomic number ZA. This formulation is applied to liquid metallic sodium at temperature 100 degrees C; these integral equations are solved in a self-consistent manner to obtain the ion-ion and electron-ion RDFS, the electron-density distribution of a pseudoatom rho (r), and the effective interatomic potential veff(r) at the same time. The ion-ion structure factor of Na at 100 degrees C, thus calculated, shows an excellent agreement with the experiment as well as the ion-on RDF; the effective interatomic potential veff(r) giving this ion-on RDF indicates a quite similar behaviour to that extracted from the measured structure factor by Reatto et al. (1986), especially near the repulsive-core region. However, the electron-ion RDF and the pseudoatom-electron density rho (r), obtained recently from the difference between structure factors from X-ray and neutron experiments, show large deviations from the calculated ones; this means that to extract these quantities the experiment should be performed in a more precise manner. For comparison, an effective interatomic potential is constructed by the use of the Ashcroft pseudopotential with a core radius 0.905 AA, which yields almost the same electron-ion RDF and the same screening charge rho (r) except near the core region in addition to the ion-ion RDF as obtained by the full self-consistent method; the Ashcroft pseudopotential is shown to be appropriate in treating liquid Na in contrast with liquid Li, where it is totally invalid.

One of the approaches to sampled-data controller design for nonlinear continuous-time systems consists of obtaining an appropriate model and then proceeding to design a controller for the model. Then, it is important to derive a good approximate sampled-data model because the exact sampled- data model for nonlinear systems is often unavailable to the controller designers. Recently, Yuz and Goodwin have proposed an accurate sampled-data model which includes extra zero dynamics, so-called the sampling zero dynamics, corresponding to the relative degree of the continuous-time nonlinear system. This paper shows that a more accurate sampled-data model is required for a controlled Van der Pol system with the relative degree two. The reason is that the closed-loop system becomes unstable when a controller design method based on cancellation of the zero dynamics is applied, and the phenomenon seems related to the instability of the sampling zero dynamics of the more accurate sampled-data model. Further, this paper derives a more accurate model than that of Yuz and Goodwin for continuous-time nonlinear systems with the relative degree two, and presents a condition which assures the stability of the sampling zero dynamics of the obtained model.

The conventional series-resonant power frequency modulated DC-DC converter with a high-frequency (HF) transformer link designed for driving the magnetron of microwave ovens has the problem of the hard switching commutation at turn-on and turn-off the active power switching devices due to the influence of the magnetizing current of the high-frequency transformer. This paper presents a novel prototype of high-frequency transformer parasitic parameters with a lossless inductive snubber and a series resonant capacitor assisted series- resonant zero current switching pulse frequency modulated DC-DC power converter, which is designed for industrial use of high power magnetron for microwave ovens. In order to implement a complete and efficient soft switching commutation, the performance of the new converter topology is practically confirmed and evaluated in the prototype of power microwave generator for plasma application from practical point of view.

The conventional series-resonant power frequency modulated DC-DC converter with a high-frequency transformer link designed for driving the magnetron of microwave ovens has the problem of the hard switching commutation at turn-on and turn-off the active power switching devices due to the influence of the magnetizing current of the high-frequency transformer. This paper presents a novel prototype of high-frequency transformer parasitic parameters with a lossless inductive snubber and a series resonant capacitor assisted series-resonant zero current switching pulse frequency modulated DC-DC power converter, which is designed for industrial use of high power magnetron for microwave ovens. In order to implement a complete and efficient soft switching commutation, the performance of the new converter topology is practically confirmed and evaluated in the prototype of power microwave generator for plasma application from practical point of view.

The conventional series-resonant power frequency modulated DC-DC converter with a high-frequency transformer link designed for driving the magnetron of microwave ovens has the problem of the hard switching commutation at turn-on and turn-off the active power switching devices due to the influence of the magnetizing current of the high-frequency transformer. This paper presents a novel prototype of high-frequency transformer parasitic parameters with a lossless inductive snubber and a series resonant capacitor assisted series-resonant zero current switching pulse frequency modulated DC-DC power converter, which is designed for industrial use of high power magnetron for microwave ovens. In order to implement a complete and efficient soft switching commutation, the performance of the new converter topology is practically confirmed and evaluated in the prototype of power microwave generator for plasma application from practical point of view.

This paper considers the problem of constructing the adaptive pole assignment control system for unknown linear time-invariant continuous-time plants using the state estimate from the adaptive observer. A similar problem has been solved by Kreisselmeier and Minamide et al. In this paper, a different type of adaptive algorithm using continuous-time least squares method with a forgetting factor as the parameter adaptation scheme is proposed, so that the adaptive control loop is simplified. The stability of the total closed-loop system is proved under the sufficient richness assumption of the filter signals without assumption of the boundedness of these signals. In particular, it is noted that this algorithm has exponential convergence rate with respect to parameter identification errors and the rate does not depend on the system dynamics. The effectiveness of the scheme proposed in this paper is confirmed by applying it to an experimental thermal system.

Single-phase current-fed PWM inverter using IGBTs has some unique advantages for small scale distributed utility-interactive power supply system as compared with voltage-fed PWM inverter. In particular, this is more suitable and acceptable for a nonisolated type utility-interactive power conditioner, which is going to be widely used for residential solar photovoltaic power generation (PVG) system in Japan. In practice, this current-fed PWM inverter has a significant disadvantage. The output current of this inverter includes large harmonic contents when the inductance of smoothing reactor in its DC side is not large enough to eliminate its current ripple components of this inverter. In order to overcome this problem, a new conceptual pulse area modulation scheme of this inverter is introduced as an alternative scheme of conventional PWM. This paper presents a new effective control implementation of used as a novel PVG conditioner using current-fed inverter which is able to reduce the harmonic contents in the output current produced by the single-phase current-fed pulse area modulated inverter even when the ripple current in its smoothing DC reactor is sufficiently downsizing. The basic operating principle of the proposed control strategy for this inverter type PV conditioner system is described, and its simulation results to confirm this operation are discussed and evaluated herein.

This paper presents a practical prototype of a new conceptual electromagnetic induction-based fluid heating appliance using a voltage source type series capacitor-compensated load resonant high-frequency inverter with a phase-shifted PWM scheme. The feasible system implementation of electromagnetic induction-based appliance liquid or gas heating appliance is described from a practical point of view, along with its operating principle in steady-state and remarkable features.

This paper describes an advanced prototype of voltage-fed zero voltage soft-switching PWM resonant inverter with an active voltage clamped capacitor, which is used in the field of consumer power electronics put into practice for high-frequency high-power induction-heated appliances. This application-specific quasiresonant inverter using the latest generation IGBTs for soft-switching can regulate its output power under a principle of a fixed frequency ZVS-PWM strategy. Its operating principal and unique features are presented as compared with a conventional quasiresonant ZVS inverter, together with its power regulation characteristics on the basis of its computer-aided simulation and experimental results. The steady-state performances of this inverter developed for multiburner type induction-heated food cooking appliance induction-heated boiler and induction-heated fryer are discussed and evaluated from a practical point of view and evaluated in experiment.

A variety of high voltage DC power supplies employing the high frequency inverter have difficulty in achieving soft switching considering a quick response and no overshoot response under the wide load conditions which are used in a medical-use X-ray high voltage generator ranging from 20 kV to 150 kV in the output voltage and from 0.5 mA to 1.25 A, respectively. The authors develop a soft switching high voltage DC power supply designed for X-ray power generator applications, which uses lossless inductor snubber-assisted series resonant inverter circuit topology with a multistage voltage multiplier instead of a conventional high voltage diode rectifier connected to the secondary side of a high frequency high voltage transformer with a large turns ratio. A constant on-time dual mode frequency control scheme operating under a principle of zero-current soft switching commutation is described. Introducing the multistage voltage multiplier, the secondary side of turn numbers and stray capacitance of high voltage high frequency transformer is greatly reduced. It is proved that the proposed zero current switching (ZCS) DC-DC high voltage converter topology with dual mode frequency modulation mode control scheme can obtain good transient response and steady-state performance in high voltage X-ray tube load. The effectiveness of this high voltage converter with a high frequency link is evaluated and discussed on the basis of simulation analysis and observed data in experiment.

The improved loss of multilayer ceramic miniaturized band-pass filters and the improvement of the Q-factors by 10 percent are shown by putting the coaxial resonators into the multilayer structure. To find this solution, several typical resonators are optimized and the relationships between the volume and Q-factors are examined, with practical ceramic material parameters.

This paper is concerned with a study on the high-frequency current source-fed type parallel inductor-compensated load-resonant inverter for an ozonizer, together with some output regulation characteristics. In addition, an effective power control method for a current-source inverter type ozonizer is introduced. This inverter can operate under the principle of the PDM (pulse density modulation) and PWM hybrid power regulation strategy. It is noted that this inverter makes the control system simple, thus leading to improve the ozone generation efficiency.

For a sampled control system, replacing zero order hold with fractional order hold has been shown to improve the stability of zeros of the system. However, it is difficult to use the fractional order hold in practice. In this study, an approximated method of using fractional order hold is proposed. The theorem for stability of zeros of the sampled system is proved as the sampling period is small. It is shown that the approximated fractional order hold has the same advantages as the accurate one. The results could be useful in the design of a digital control system.

It is desirable that a plant has all stable zeros in many control schemes. Stability conditions of sampled multivariable systems have been considered by (Hayakawa et al., 1983). They have shown how the zeros of the sampled system are located when the sampling period tends to zero. Their result has shown that those zeros corresponding to continuous-time zeros approach 1 and the remaining zeros converge to the specific constant values determined by some definite polynomials. The stability condition of the former zeros has been given by them. Some zeros of the latter reach -1 and there remains the possibility that they approach from inside the unit circle. It is an unresolved problem. The purpose of this paper is to give an answer to this problem. It shows when the zero of sampled two-input two-output, third order systems goes to -1 from inside the unit circle.

To find a more convenient and tolerable schedule than the tri-weekly or weekly schedules, we conducted a dose escalation study of bi-weekly docetaxel.Between March 1998 and June 1999, 16 patients entered this phase I study. The starting dose was 40 mg/m2, with planned dose escalation to 45, 50 and 55 mg/m2, in consecutive patient cohorts. Patients continued to receive the assigned treatment at the same dose level bi-weekly, provided that they did not develop progressive disease, refuse further treatment, or experience unacceptable toxicity.Grade 4 neutropenia lasting for more 4 days was seen at dose level 3 in all three patients. Only one patient who had previously received intensive chemotherapy required granulocyte colony stimulating factor (G-CSF) to prevent neutropenic fever and there were no actual episodes of neutropenic fever. Grade 3 asthenia and Grade 3 elevation of serum glutamic oxaloacetic transaminase were noted in only one patient treated at a dose of 40 mg/m2. Grade 3 skin toxicity and grade 2 elevation of serum glutamic oxaloacetic transaminase were seen in only one patient treated at a dose of 55 mg/m. Cumulative toxicity was not severe in all patients. Although grade 3 and/or grade 4 neutropenia were noted in eight patients (50%), all except one who received treatment at dose of 55 mg/m2 did not need G-CSF. Nail toxicity and peripheral edema seemed to be related to the number of treatment cycles. Severe fatigue and asthenia were never seen in all patients.1) The maximum-tolerated dose of docetaxel when administered by this bi-weekly schedule was 55 mg/m2; 2) Docetaxel administered on a bi-weekly basis well tolerated.

We analyzed the ability of a recombinant replication-defective adenovirus vector with the carcinoembryonic antigen (CEA) promotor to transfer the thymidine kinase gene of herpes simplex virus (HSVtk) into gastric cancer cells to confer sensitivity to ganciclovir (GCV). CEA-producing gastric cancer cell lines (MKN28 and MKN45), a CEA-nonproducing gastric cancer cell line (MKN1), and a human uterine cervical cancer cell line (HeLa) were infected with a recombinant adenovirus carrying lacZ reporter gene coupled to the CEA promoter (AdCEAlacZ). The efficiency of AdCEAlacZ-mediated gene transfer was correlated with the amount of CEA produced by each cell line. Furthermore, the 50% growth inhibitory concentrations (IC50) of GCV were 21 and 5.8 microm for MKN28 and MKN45, respectively, when infected with a recombinant adenovirus carrying the HSVtk gene coupled to the CEA promoter (AdCEAtk). However, MKN1 and HeLa cells infected with AdCEAtk remained resistant to GCV (IC50300 microm of GCV). In addition, a bystander killing effect was demonstrated against MKN45 cells when only 20% of AdCEAtk-infected cells were mixed with uninfected cells. These data indicate the potential for targeted gene therapy using the cell type-specific promotor of the CEA gene against gastric cancers that produce CEA.

Perfect extraction of intrinsic membrane proteins or enzymes from intact cells and reconstitution of them without any denaturation and deactivation are basic requirement in investigation of the function of membrane proteins and/or the utilization of them in membrane protein engineering. For this purpose, artificial cell, liposome, seems to be a desirable and promising tool in both basic investigation and application.

Optical properties in conjugated polymers such as poly(p-phenylenevinylene) and poly(9,9-dialkyl-fluorene) have been studied using time-dependent density functional theory. In the calculations of the optical properties, real-space and real-time techniques are employed. We follow the linear responses of the systems under externally applied perturbations in the real time. To estimate the polymer spectra, we have calculated the responses of oligomers of different lengths and obtained the extrapolated values. The estimated polymer spectra agree with the experiments reasonably well.

To avoid water penetrating into cable insulation through jacket two simple structures are considered; one is that the metal laminated tape layer is positioned beneath the jacket, and the other is on the cable core. This paper outlines the former case, which is furnished with a newly developed laminate lead tape layer beneath the PVC jacket. The new laminated lead tape is composed of a semi-conducting PVC layer, lead foil layer and reinforcing plastic layer. This tape was found to be applicable to large-sized cables without any trouble during manufacturing. This XLPE cable with new laminated waterproof jacket was clear to have excellent waterproofness and higher reliability more than the XLPE cable with PVC jacket through long-term test in water immersion and can be used satisfactorily for actual cable lines.