bluuebunny/crossref_metadata_2025 huggingface dataset:
Production of highly-charged ions by nitrogen gas target irradiated with ultrashort high-intensity pulse laser
Authors: Namba Shinichi , Kawachi Tetsuya , Hasegawa Noboru , Nagashima Keisuke , Sukegawa Kouta , Kado Masataka , Tanaka Momoko , Daido Hiroyuki , Kato Yoshiaki
Published: December 2018

High-density nitrogen gas was irradiated with an ultrashort high-intensity pulse laser (pulse width: 1.5 ps, intensity:≥ 10 ^{15} W/cm ^{2} ). It was found that highly charged ions were produced effectively as the gas density became higher. From distribution of population densities of high-lying levels of lithium like nitrogen ions, the electron temperature in a recombining phase was estimated. This electron temperature together with a calculation using a collisional-radiative model, in which doubly excited levels of beryllium like ions are included, indicated that the electron density was n_{e} = 3× 10 ^{19} cm ^{-3} . Moreover, the spectra also showed that population inversions between some excited states of hydrogen-, helium-, lithium like nitrogen ions were generated under this plasma conditions.
Diagnostics of ultrashort electron bunch by coherent transition/diffraction radiation
Authors: Watanabe T. , Sugahara J. , Yoshii K. , Ueda T. , Uesaka M. , Yoshimatsu T. , Kondo Y. , Sugiyama Y. , Sasaki S. , Ishi K. , Shibata Y.
Published: December 2018

Measurements of longitudinal bunch length of picosecond electron bunches have been performed by the femtosecond streak camera, the interferometer and the polychromator and their results were compared with one another. As regards the radiation, transition radiation and diffraction radiation were investigated through the diagnostics. As a result, the fine agreements between them within 200 fs were obtained and the reliability of the interferometer and the polychromator for the diagnostics of less than picosecond electron bunch were verified. Furthermore, nondestructive diagnostics for subpicosecond bunches was performed utilizing coherent diffraction radiation (CDR) interferometry.
High quality electron beam science at Waseda University
Authors: Kashiwagi S. , Hama Y. , Hara S. , Ishikawa H. , Kuroda R. , Kobuki T. , Oshima T. , Sato K. , Washio M. , Yada A. , Urakawa J. , Hayano H.
Published: December 2018

At Waseda University, we have started a new research project named"High-Tech Research Center Project" which is supported by the Ministry of Education, Culture, Sports, Science and Technology. In this project, a laser photo-cathode rf-gun with 1.6 acceleration cells has been installed for production of low emittance and short bunched electron beam. The high quality electron beam is very powerful tool for the study on radiation physics, radiation chemistry, material science etc. Development of pulsed X-ray generation by the inverse Compton scattering between high quality electron beam and laser pulse obtained from an all-solid-state Nd:YLF laser system will be started in 2001 fiscal year. The system will be applied to the pulse radiolysis experiments for the studies on radiation physics and chemistry. In this paper, we will describe the X-ray generation experiment at Waseda University.
Force measurements for levitated bulk superconductors in electromaglev system
Authors: Tachi Yasuharu , Nishikawa Tsuyoshi , Sawa Koichiro , Murakami Masato , Iwasa Yukikazu
Published: December 2018

We have directly measured the levitation force of levitated bulk superconductors in an electromaglev system. The levitation force had a hysteresis loop during increasing and decreasing field processes. Such a hysteretic behavior can be explained in terms of hysteretic penetration of external field to the superconductor. Based on such magnetization, we performed numerical simulations of the levitation forces, which were in fairly good agreement with experimental data.
Study on mechanical jointing of high temperature superconductors
Authors: Ito S. , Hashizume H. , Kitajima S.
Published: December 2018

In the present design, the superconducting magnets can not be separated into several parts of the magnet, because of problems caused by heat generation and electromagnetic force. For the future commercial fusion reactor, however, the mountable magnets are desired to make the reactor maintenance and repair easy. In this research, therefore, a study on mechanical jointing of HTc S.C. will be performed to clarify its possibility. Two methods of the jointing are employed to compare the results. In the first method a piece of S.C. tape is put on another tape where the stress between two tapes is controlled. In the second method cross sections of two S.C. tapes are directly jointed. The voltage drop is measured to estimate the resistance in those regions and the possibility of jointing is discussed.
Synthesis and magnetization of high-T_c bulk superconductors and their application as superconducting permanent magnets
Authors: Mizutani U. , Ikuta H. , Oka T. , Itoh Y. , Yanagi Y. , Yoshikawa M.
Published: December 2018

We synthesized the c-axis oriented single-domain Ag-bearing Sm123 superconductors with 36∼mm in diameter and magnetized them by either static field or single pulsed-field. By using the Sm123 bulk superconductor magnetized by static field, we succeeded in fully magnetizing the Nd-Fe-B plate with 50 × 50 × 5 mm ^3 in size by scanning the plate over the bulk superconductor. As another example, we present the construction and performance of a face-to-face superconducting permanent magnet system, which is driven by magnetizing the Sm123 superconductor cooled to 35 K by the pulsed field technique we developed.
Development of mechanical SMA urethral valve with transcutaneous energy transmission system
Authors: Tanaka Mami , Sakamoto Tetsushi , Wang Feng , Namima Takashige , Tanahashi Yoshikatsu , Chonan Seiji
Published: December 2018

This paper presents the development of a mechanical SMA urethral valve driven by a portable transcutaneous energy transmission system, which is powered by batteries. Structure of the valve was improved by introducing a bite mechanism in order to prevent the pinch of urethra by the valve. The cycling characteristics and energy transmission efficiency were examined by laboratory tests. Experimental results show that the stable operation can be obtained by introducing a voltage regulating circuit to the energy transmission system and utilizing the sinusoidal oscillation in the energy transmission system can enhance the transmission efficiency. Furthermore, the function of the valve system was tested by the in vitro and in vivo animal experiments.
Analysis of the QRS complex in three-dimensional magnetocardiogram by use of a wavelet transform based band pass filters
Authors: Liu Mai , Uchikawa Yoshinori
Published: December 2018

A wavelet transform based band pass filters were used to analyze the QRS complex in a three-dimensional magnetocardiogram (3-D MCG) recorded from normal subjects and a patient with anterior myocardial infarction (MI). The high frequency components of the QRS complex related to the ventricular late fields (LF) were detected from the patient with anterior MI at different scale. The weak magnetic signals were quantified by calculating root-mean-square (RMS) value at different scale. In order to discuss the activities of the heart between the normal subject and the patient with anterior MI, the spatial energy distribution (SED) of the QRS complex was also evaluated by displaying isoenergy contour maps at different scale.
Profile of development to genes under extremely low frequency magnetic fields with caenorhabditis elegans
Authors: Miyakawa Tomokazu , Harada Shin-ichi , Ishimori Takayuki , Yamamoto Hiroshi , Hosono Ryuji , Yamada Sotoshi
Published: December 2018

Responses of the small heat shock protein gene, hsp-16, were examined in transgenic Caenorhabditis elegans exposed to extremly low frequency magnetic fields (ELFMFs). Expression of the hsp-16-lacZ gene was enhanced when transgenic animals were exposed to magnetic fields up to 0.5 T at 60 Hz. The hsp-16 promoter was more efficiently expressed at the embryonic than at the post-embryonic stage irrespective of exposure. Promoter activity was more sensitive to the stimulus in the intestine at the post-embryonic stage. Evidence is presented that the induction occurs at the transcriptional step of hsp-16.
Magnetically induced currents in a three-dimensional human body model
Authors: Golovanov Carmen , Urma Daniela , Albu Mihaela , Ioan D.
Published: December 2018

Transmission and distribution lines together with the power transformers produce electromagnetic fields that represent a subject for many controversial issues. A special problem is to evaluate the electric field induced in a human body, when this is exposed to low-frequency magnetic field. In this paper, a 3D human body model is proposed in order to determine the current densities induced by a 50∼Hz magnetic field.
Visually evoked magnetic fields associated with pattern recognition
Authors: Huang Shiann-fong , Iramina Keiji , Yumoto Masato , Ueno Shoogo
Published: December 2018

In this study, we are interested in the endogenous negativity of the earlier negative component (designated NA) for observing some aspects of cognitive processes. We recorded the visual NA magnetic field with a 204-channel whole-scalp SQUID gradiometer and estimated the equivalent current dipoles (ECD) to clarify the source localization of NA. Visual evoked magnetic fields (EMFs) were recorded during a simple response task (SRT) and a discriminative response task (DRT) to examine the endogenous negative component, NA. The characters of the NA curves for all subjects were the same [1]. The ECD sources for one subject were localized in the parietal section of the brain. Our data suggest the possibility of visual NA research in evoked magnetic fields.
Cleavage pattern modulation of frog's egg under magnetic fields of 10 tesla order
Authors: Iwasaka M. , Ueno S. , Shiokawa K.
Published: December 2018

In the present study, a possible influence of intense magnetic fields on cleavage patterns during the early embryonic development of frogs was studied. The early cleavages in Xenopus laevis were disordered by horizontal magnetic fields of 10 T order. However, the magnetic field effect did not remain until when they become tadpoles.
Frequency characteristics of a magnet-magnetic fluid element on a vibrating table
Authors: Sudo S. , Ise K. , Nishiyama H. , Tani J.
Published: December 2018

The results of an experimental study of frequency characteristics of a permanent magnet-magnetic fluid element on a vertically vibrated table were presented and discussed in some detail. Some effects of excitation frequency on the motion of the magnet-magnetic fluid element were noted. The dynamic behavior of magnetic fluid surface was also revealed by two high speed digital cameras.
Haptic sensor for monitoring skin conditions
Authors: Tanaka Mami , Hiraizumi Jun , Lévêque Jean Luc , Chonan Seiji
Published: December 2018

The present paper is concerned with the development of a haptic sensor that evaluates the human skin conditions. The base of the sensor is an aluminum shell, around which a rubber sponge layer, PVDF film, a protective layer of acetate film and gauze are stacked in sequence. The sensor is attached on to the tip of an elastic cantilevered beam and pressed against an the surface of the skin. It is then slid over the skin to collect the surface morphological features. Characteristics of data are examined by calculating the variance and the power intensity ration over several segmented frequency ranges. The sensor is applied to seeing the variation of skin conditions depending on ages.
FMR Investigation of the amorphous CoFeSiB glass-covered wires in the presence of mechanical tension
Authors: Tufescu Florin Mihai , Chiriac Horia , Óvári Tibor-Adrian , Stancu Alexandru
Published: December 2018

Results on the FMR investigation of the effect of applied tensile stresses on the surface magnetic anisotropy of Co6 _{8.25} Fe _{4.5} Si _{12.25} B _{15} amorphous glass-covered wires are reported. Axially applied stresses lead to a decrease of the resonance field and absorption intensity that correspond to the main resonance peak, indicating a reinforcement of the circumferential magnetoelastic anisotropy from the wire's surface region. The FMR spectra determined at 8.5 GHz -- the lowest employed frequency of the microwave field -- display a compound aspect, i.e. a secondary resonance peak is observed at slightly larger values of the dc magnetic field. This fact indicates that one can detect a region with different anisotropy direction towards the wire's inner zone when the magnetic penetration depth is large enough. The obtained results are valuable as regards the sensor applications of such materials.
Reversible structural phase transition in Ni-Mn-Ga alloys in a magnetic field
Authors: Cherechukin A.A. , Dikshtein I.E. , Ermakov D.I. , Glebov A.V. , Koledov V.V. , Shavrov V.G. , Takagi T. , Tulaikova A.A.
Published: December 2018

A reversible field-induced structural phase transition in shape-memory ferromagnetic alloys Ni _{2+x} Mn _{1-x} Ga has been observed at fixed temperature and pressure in magnetic fields about 100 kOe. The theoretical results are in qualitative agreement with experiment.
A fast forward analysis scheme for nonlinear static electromagnetic problems
Authors: Chen Zhenmao , Preda Gabriel , Mihalache Ovidiu , Miya Kenzo
Published: December 2018

In this paper, a rapid forward scheme is proposed for simulation of the static magnetic flux leakage (MFL) signals arisen from an object of ferromagnetic material. By storing precalculated distribution data of the unflawed magnetic field into a database, the analysis region for solving the field perturbation due to a crack is greatly reduced by applying the feature that only the magnetic field in the vicinity of a crack can be significantly perturbed due to the presence of a crack. Having implemented the new scheme into an FEM-BEM hybrid code of the polarization method, the validity of the proposed method is proved by comparing numerical results of the fast forward solver with those obtained by the FEM-BEM polarization code.
Forward solution method for the reconstruction of the shape of thin metal deposit on plate specimen
Authors: Pávó József
Published: December 2018

A forward calculation method is presented for the analysis of the interaction of a pancake type eddy current testing (ECT) coil and an arbitrary shape thin metal deposit located on the reverse side of a plate specimen. The deposit is modelled as an infinitesimally thin layer where the impedance type boundary conditions are enforced. The given boundary conditions result an integral equation which solution provides the actual distribution of secondary sources modelling the presence of the deposit. Knowing these secondary sources, the signal of the ECT probe is calculated. Based on the developed forward solution, a proposal for a method reconstructing the shape of the deposit from measured ECT signal is outlined.
A numerical approach for current source detection
Authors: Albanese Raffaele , Rubinacci Guglielmo , Tamburrino Antonello , Villone Fabio
Published: December 2018

The paper presents the main features of a numerical model for the reconstruction of current sources, on the basis of the knowledge of a set of magnetic measurements. The problem, one of the key issues in biomagnetics research, is solved by extending a method developed in the frame of NDE, for the detection of volume cracks.
A soft computing approach to reconstruct defects on metallic plates
Authors: Morabito F.C. , Calcagno S. , Versaci M.
Published: December 2018

Eddy current techniques (ECT) for Nondestructive Testing and Evaluation (NDT/NDE) of conducting materials is one of the most application-oriented field of research within electromagnetics. In this work, a fuzzy approach is proposed to estimate the presence of holes in metallic plates starting from a set of experimental eddy current measurements, carried out at the NDT Lab in Reggio Calabria. The above inverse problem is solved by means of a system that extracts information on the specimen under test from the measurements and implements a priori constraints to facilitate the detection and characterization of the defect. The method utilizes the concepts of fuzzy inference in order to estimate the location of the defect from a reduced set of features.
Reconstruction of Parallel Cracks by ECT
Authors: Cheng Weiying , Miya Kenzo
Published: December 2018

This paper presents a two-step algorithm to reconstruct parallel cracks from ECT (eddy current testing) signals. The number, the approximate locations and lengths of cracks are determined in the separation stage by employing the eddy current imaging, and the profiles of cracks are obtained in the reconstruction stage.
A novel efficiency measurement of moving-magnet-type linear oscillatory actuator
Authors: Tsutomu Mizuno , Takuya Yaegashi , Masaki Takai , Makoto Utsuno , Hideo Yamamoto , Kouyou Shibuya , Hajime Yamada
Published: December 2018

This paper deals with the efficiency characteristics of a moving-magnet-type linear oscillatory actuator (LOA) for compressor by using a novel measuring method. In this measurement, another linear motor is used as the load instead of compressor. The relationship between efficiency and the phase of the load current is investegated. Maximum efficiency of the LOA reaches to 87% at the output power of 61 W.
The magneto-impedance (MI) effect of coupled magnetic ribbons in a non-uniform magnetic field
Authors: Iida Satoko , Suzuki Daisuke , Kambe Shiro , Ishii Osamu
Published: December 2018

We investigated the application of a magnetic ribbon to a highly sensitive magnetic sensor. The sensor employs the impedance change in a coupled magnetic ribbon when a radio frequency (rf) current is passed through it and an external magnetic field is applied. When the non-uniform external field was applied the coupled ribbon structure was conformed to have high sensitivity, which was about ten times higher than that in the uniform external field. This phenomenon was attributed to the magnetostatic coupling between coupled magnetic ribbons.
Object-oriented genetic algorithms for two-dimensional design optimization of the magnetic circuit of a mobile magnetic resonance device
Authors: Popella Hartmut , Henneberger Gerhard
Published: December 2018

The mobile usage of a magnetic resonance imaging device commonly known as MRI requires a handy kind of magnetic circuit device for production of the main magnetic field B_0 . This device is called a Mobile Universal Surface Explorer (MOUSE). The requirements of homogeneity and field strength for MRI applications as well as low weight make great demands on the geometrical shape of the magnetic circuit. By genetic optimization of several FEM models of the MOUSE a suitable solution shall be found which meets the demanded requirements. The paper presents a genetic optimizer for static computation of the MOUSE' field distribution and describes the implementation using object-oriented design patterns.
Inversion of eddy current NDE signals using genetic algorithm
Authors: Yusa Noritaka , Chen Zhenmao , Miya Kenzo
Published: December 2018

The present paper presents an inversion scheme that reconstructs crack profile from eddy current signals. The scheme is based upon the genetic algorithm and reconstructs crack profile from the signals obtained by numerical simulations with use of an accelerated FEM-BEM coupling code. The cracks are assumed to have uniform electrical conductivity in order to model natural cracks that occur in steam generator tubes of pressurized nuclear power plants. On the basis of calculated eddy current signals in the previous generations, the inversion scheme is accelerated by eliminating individuals that are obviously different from the global optimum solution. Reconstruction results are shown in the paper, which reveal that the scheme is very promising.
Semi-analytical electromagnetic field computation
Authors: Watazawa Yasuyuki , Hayano Seiji , Saito Yoshifuru
Published: December 2018

Any of the numerical methods for electromagnetic field analysis essentially require a subdivision of a problem region. By notifying this subdivision, we have previously proposed a new methodology by applying the analytical solution to each of the discretized parts. The first trial of this semi-analytical electromagnetic filed computational methodology has made it possible to simulate the complex electromagnetic field distributions not obtainable by the conventional numerical schemes, such as finite and boundary elements means. However, our semi-analytical method encounters some difficulty when analyzing the high frequency electromagnetic field distributions because of the displacement currents.In the present paper, we propose a new semi-analytical approach taking the displacement currents into account to overcome this difficulty.
Magnetic sensor signal analysis by means of the image processing technique
Authors: Senoo Isamu , Saito Yoshifuru , Hayano Seiji
Published: December 2018

We have been proposing the image processing methodology where the human voice signals are transformed into the three-dimensional image data by means of the three-dimensional Lissajous diagram [1]. In this paper, we apply the image cognition technology to the cognition of the magnetic sensor signals. At first, the time domain signals are converted into the three-dimensional images, which construct the database system. Secondly, when we measure a time domain signal, this signal is also converted into a three-dimensional image. This three-dimensional image becomes an input vector of a least squares means. Least squares solution gives a composite signal as a linearly combined database signals. Extracting the most dominant term from the least squares solution reveals the cognized signal. Thus, we have succeeded in the time domain magnetic sensor signal cognition by means of the image cognitive technology [2].
Magnetic fields control by single-sided exciting coils
Authors: Ema Akira , Hayano Seiji , Saito Yoshifuru
Published: December 2018

In the present paper, we propose the methodologies in order to realize the desired magnetic field distributions by using single-sided exciting coils. As a result, it is revealed that a combination of the least squares and the generalized vector sampled pattern matching method suggests the practically realizable exciting coil layout.
Magnetic sensor signal analysis
Authors: Shigeta Yukiyasu , Hayano Seiji , Saito Yoshifuru
Published: December 2018

In the present paper, we propose a method of analysis for the magnetic sensor signals. Based on the physical characteristic value such as a time constant of the electric circuits, our methodology tries to work out an equivalent characteristic value reflecting the physical property of the target metallic material [1,2,3]. Our smart magnetic sensor developing is to recognize a datum from the signal database. This is applied to the space domain signal cognition. As a result, this paper reports that the equivalent characteristic value is an extremely useful quantity in order to examine the physical nature of the target.
Simulation of visual prosthesis in virtual space
Authors: Terasawa Y. , Fujikado T. , Yagi T.
Published: December 2018

In developing a visual prosthesis, it is essential for us to determine its specifications which meet the minimal needs in daily lives of patients. For that purpose, we have proposed a prosthetic vision simulator which enables us to experience prosthetic vision in the virtual space. This time, we applied this system to quantitative evaluation of the reading ability. Experimental results suggested that the electric current intensity in stimulation has small effects to the reading ability.
Characteristics of the forced vibration with magnetic damping
Authors: Tanaka Yoshikazu , Horie Tomoyoshi
Published: December 2018

It is required to clarify the characteristics of forced vibration with magnetic damping for an earthquake-resistant design of conductive thin shell structures located in an electromagnetic field. In this paper, the characteristics of forced vibration are examined using finite element tightly coupled analysis and single-degree-of-freedom coupled model. The results show that the change of resonance frequency is different from that of general viscous damping problems for some combinations of material properties and magnetic fields. It is pronounced when the eddy current decay rate is close to the natural period of the structure.
Some effects of grain boundaries on the field distribution on the surface of grain oriented electrical steels
Authors: Moses A.J. , Konadu S.N.
Published: December 2018

A non-destructive system using a Hall effect I.C. sensor has been used to measure the distribution of the vertical component of stray magnetic field on the opposite surfaces of a magnetised specimen of high permeability, grain-oriented electrical steel. An optical microscope was used to establish positions of grain boundaries in order to explain differences in field profiles outside the systematic accuracy of measurements. It was found that unlike previously assumed, grain boundaries may not necessarily be perpendicular to the sheet surface so different field distribution may occur. This should be considered when evaluating local power loss from surface sensor movements. Future studies are also necessary to quantify the effect of this phenomenon in the interpretation of surface or bulk properties of electrical steels using surface field sensors.
Compact inverse compton scattering hard X-ray source based on X-band linac
Authors: Fukasawa Atsushi , Kobayashi Tetsuya , Uesaka Mitsuru , Urakawa Junji , Higo Toshiyasu , Akemoto Mitsuo , Hayano Hitoshi
Published: December 2018

Compact inverse Compton scattering hard X-ray source based on the X-band linac is numerically designed. The theoretical scaling law for emittance vs. charge / RF frequency was confirmed by the numerical analysis. The 3.5 cell RF gun with the field strength at the cathode surface 140 MV/m can produce the 2.1 MeV, 240 pC electron bunch, although the energy spread, 8% only 10^{5} photons/shot in this system, we have proposed several schemes to achieve 10^{11} photons/10ms based on state-of-the-art technologies.
High brightness gamma-ray generation via laser-electron collision: Experiment and quantitative considerations
Authors: Dobashi K. , Fukuda M. , Hirose T. , Kamiya Y. , Sakai I. , Aoki T. , Higurashi A. , Oshima T. , Washio M. , Kurihara Y. , Okugi T. , Omori T. , Urakawa J.
Published: December 2018

We performed an experiment of high brightness gamma(γ)-rays production through laser-electron(e ^{-} ) collisions using an insertion device with a short focal length of laser optics. Number of generatedγ-rays with the bunch length of 26 psec (r.m.s) was 0.92 × 10^5 /bunch, thus leading to brightness 2.5 × 10^{17} /(mm ^2 · mrad ^2 · 0.1% band-width · sec). Quantitative considerations on the basis of numerical model permitted to elucidate how characteristics of ^{-} and laser beam influence collision mechanisms.
Computational modeling of electrodynamic and transport phenomena in materials processing systems
Authors: Li B.Q. , He R.
Published: December 2018

This paper discusses the numerical modeling of coupled electromagnetic and transport (fluid flow and heat and mass transfer) phenomena in materials processing systems under both terrestrial and microgravity conditions. Two types of magnetically induced transport phenomena are considered and both require iterative numerical computations. For the former, the flow is activated through Faraday's law and the computational methodology entails the use of the boundary element method to model the free space region and of the finite element method to model the interior region of the liquid. Computations involve the iterative solution of magnetic fields, fluid flow and surface stress balance when free surface deformation occurs. For the later, the fluid motion is suppressed by an applied DC magnetic field and flow and magnetic fields are coupled so that iterative computational procedure is again required. For this later case, computational costs are substantially reduced by carefully designing the finite element global matrix structure.
Neural networks for environmental data processing: a research project of relevant national interest for the Italian Government
Authors: Burrascano Pietro
Published: December 2018

A group of Italian researchers in the field of neural processing systems proposed to the Italian government a project in the field of Neural Networks for environmental data processing. The project has been funded, and started to be operative at the beginning of 2001. A major objective of the project is that of focusing the potential of the research group in the field of neural modelling to the problem of environmental management in order to produce, at the end of the project period, powerful prediction tools in environmental applications. Air and electromagnetic pollution together with water resources management are the specific environmental problems to which the predictive neural models will be particularised and applied.
Non-linear control of electrically driven micromirrors by means of inverse dynamics
Authors: Enge Olaf , Maißer Peter , Jungnickel Uwe
Published: December 2018

Based on a unified mathematical approach for modelling electromechanical systems (EMS), this paper shows a method to control dynamically the motion of an electrically driven micromirror on a nominal trajectory. For every time interval, this is done in three steps: Inverse dynamics of the mechanical subsystem, calculation of appropriate charges to produce the control forces electrically, and inverse dynamics of the electrical subsystem. The usage of an augmented PD-control law in the first step guarantees global exponential stability of the mirror on the nominal trajectory. The second step is carried out by an optimization method of linear programming. In the third step, the voltages are computed neglecting the dynamics of the electrical subsystem. Finally, these voltages are applied at the simulation model of the micromirror.
Broad band RF cavity for ion synchrotron using all-pass network
Authors: Rizawa Takahito , Tamura Hitoshi , Sato Kenji
Published: December 2018

A new concept of a tuning free cavity for an ion synchrotron is described, which is based on an idea of applying an all-pass network to a ferrite LC resonator. Though the new type cavity has a smaller and simpler structure than bias-tuned one, it can produce comparably high RF voltage and a wide frequency range. After high power tests of newly developed ferrite materials and a proto-type cavity proved the concept practicable, beam acceleration tests were performed at HIMAC successfully. The course of developing the cavity is described with its unique merits and further applicability.
Analysis on saccade-related EEG with independent component analysis
Authors: Funase Arao , Yagi Tohru , Barros Allan K. , Kuno Yoshiaki , Uchikawa Yoshiki
Published: December 2018

The purpose of our study is to analyze the relationship between the fast eye movements, i.e., "saccade", and the electroencephalogram (EEG). The recorded EEG during saccade was analyzed with the independent component analysis (ICA) method. During visually guided saccade experiments, we observed a sharp change of the ICA signals more frequently immediately before eye movement than at other peak point of reference signals, while this was not the case under the condition of no eye movement. These results indicate that the phenomenon of signal change is possibly related to the motion processing of saccade, or to the attention to the visual stimulus.
Capacitance computation of thin conductors with the fast multipole method
Authors: Buchau André , Rucker Wolfgang M.
Published: December 2018

Computing the capacitance coefficients of a multiconductor system embedded in multiple piecewise homogeneous dielectrics with the boundary element method in combination with the fast multipole method, the memory requirements and the computational cost for the solution of the system of linear equations are approximately proportional to the number of unknowns. In this paper it will be shown, that the calculation of the free charges on the conductors and with it the calculation of the capacitance coefficients can be accelerated, if the fast multipole method is also used for the post-processing.
Orthogonality of the eigenfunctions of the plane transient eddy current problem
Authors: Ehrich Matthias , Fichte Lars Ole , Lüer Michael
Published: December 2018

The plane transient eddy current problem of a system of N arbitrary conductors with different magnetic permeability is solved in the time domain by time-separation. This leads to an eigenvalue problem which we treat by evaluating several volume and boundary integral equations for the vector potential. It is shown that the eigenfunctions of the different integral equations form complete orthogonal systems. As examples of application we calculate the transient behavior of the conductor system after connecting it to sources of direct voltage or direct current at time t=0.
Dynamic shape control of beam-type structures by piezoelectric actuation and sensing
Authors: Irschik Hans , Krommer Michael , Pichler Uwe
Published: December 2018

In the present paper the concept of dynamic shape control of structures is addressed. The term "shape control", not to be confused with automatic control, means to identify the spatial distribution (or shape) of an actuating control agency, such that a structural displacement field with a desired spatial distribution (or shape) is reached. This field aspect requires a spatially distributed control actuation, which, in the present paper, is performed by means of assigned piezoelectric eigenstrains. The goal of our proposed dynamic shape control procedure is to shape the piezoelectric actuation such as to obtain a displacement field coinciding with a dynamic displacement field induced by external forces. Equivalently, we may eliminate the force induced dynamic displacements. Bending vibrations of straight composite piezoelectric beams are studied in more detail. First, the coupled electro-mechanical field equations are developed and then the dynamic shape control problem is solved in closed form for this coupled formulation. It turns out that exact elimination of force induced vibrations is possible when the shape of the piezoelectric actuation coincides with a statically admissible bending moment distribution of the force loaded beam. Distributions characterizing non-unique solutions are discussed, and aspects of collocated sensing are addressed.
A communication system for ALS patients using eye blink
Authors: Takeshita Kazuhiro , Uchibori Akihiko , Mizukami Yoshiki , Satoh Taiji , Tanaka Kanya , Uchikado Shigeru
Published: December 2018

The purpose of our research is to design a communication system for ALS patients who have difficulty in using their hands and mouth. In the proposed system, eye blink is adopted as a switch to tell judging patient's intention by using several image processing. A list of intentions is displayed on the PC monitor; each intention is displayed with an adequate time interval. The patient can select the candidate intention by blinking his/her eye.

To investigate the efficiency of the proposed system, we conducted experiments on 10 subjects. The experimental results show that the proposed system distinguished conscious and unconscious eye blink.
A dry-contact method for transmitting higher frequency components of ultrasound
Authors: Tohmyoh Hironori , Saka Masumi
Published: December 2018

Although it is possible to achieve higher resolution by conventional ultrasonic technique, it suffers from a disadvantage because testing has to be performed in a liquid medium. In contrast with the conventional technique, a dry-contact ultrasonic technique, which can be carried out without wetting the testing parts, is preferable. In a new technique that is developed by the authors, a dry-contact interface is used by inserting a membrane between water and the tested parts. Experiments were also carried out in search of membrane that can transmit higher frequency components. Dry-contact ultrasonic transmission using two kinds of plastic films and a silicone rubber sheet was performed on an acrylic resin. It was shown that the plastic films far excel in transmitting higher frequency components than the silicone rubber sheet.
Robust control for nonlinear dynamic systems
Authors: Im Kyumann , Ham Cheoljoo , Ham Woonchul
Published: December 2018

In this paper, a robust control scheme for a class of nonlinear dynamical system is proposed by using output-feedback linearization method. The presented control scheme is based on the VSS. We assume that the nonlinear dynamical system is minimum phase, i.e., the relative degree of the system is p=r_1+r_2+ … +r_m ≤ n and zero dynamics is stable. We also assume that the states of zero dynamics are not accessible. It is also shown that the global asymptotically stability is guaranted. And we verified that the proposed control scheme is then applied to the control of a two degrees of freedom (DOF) robotic manipulator with payload.
Remarks on multi layer neural networks involving chaos neurons
Authors: Takahashi Kazuhiko
Published: December 2018

This paper investigates multi layer neural networks that involves the chaos neurons to achieve high efficiency of neural networks learning. Two types of neural networks are proposed. One of the multi layer neural network has the chaos neural network in its hidden layer. The other multi layer neural network is composed only using the chaos neurons. The learning ability of the neural networks involving the chaos neurons and/or chaos neural network is evaluated by benchmark experiment with XOR problems. Experimental results show the feasibility of the chaos neurons to improve the learning of neural networks. As an engineering application example, the multi layer chaos neural network is applied for identifying nonlinear dynamical systems and its effectiveness is demonstrated.
Magnetoelastic stresses in a circular shell subject to a point magnetic source
Authors: Lin Chun-Bo , Chen Shin-Cheng
Published: December 2018

The magnetoelastic problem of a circular shell subjected to the magnetic loadings is considered. In this paper the magnetic loadings include a point magnetic source in the domain outside or inside the circular shell or a uniform magnetic induction applied at infinity. Based upon the complex variable theory and the method of analytical continuation, the solutions of magnetic field quantities and the tangential magnetoelastic stresses in the shell and its outer and inner regions are obtained. The tangential magnetoelastic stresses for a thin shell in air under different magnetic loadings are also provided and compared with some special case of which the solution can be found in the literature, which reveals that the present solution is exact and general.
Eigen-material constants, mode and failure criterion for piezoelectric media
Authors: Kuang Zhen-Bang , Zhou Zhi-Dong , Chen Yue , Zhao She-Xu
Published: December 2018

In this paper the normalized generalized stress and strain vectors in 9-D space are introduced. A method of constructing the eigen-compliance constants and material modes for the piezoelectric material is presented, which is applied to design a new failure criterion based upon the concept of strain energy modes. In this theory, normalized generalized stress and strain vectors can be additively decomposed into nine independent and non-interaction modal components {\overline T}^{(i)} and {\overline S}^{(i)} respectively, whose directions are called material modes, and the total strain energy is additively composed with nine independent modal energy components. Along each material mode, there is a modal energy given by {\overline T}^{(i)}{\overline S}^{(i)}/2 and it is assumed that the role of different modal energies is different in the failure event. It is postulated that the failure will occur when one of the modal energies or an appropriate linear combination of these energy modes reaches a critical value. PZT-4 piezoelectric ceramic is used as a numerical example to demonstrate the adequacy of the theory with experiment for the piezoelectric failure problem. The calculated result seems to be in good qualitative agreement with experimental data.
Optimal design of magnetic scale for linearizing magnetic flux density and force
Authors: An Kwang-Ok , Im Chang-Hwan , Lee Chang-Hwan , Jung Hyun-Kyo
Published: December 2018

The new design of magnetic scale that uses magnetic levitation force is proposed. The optimal design for linearizing magnetic flux density and force is presented. The linearity of magnetic flux density and force can be improved by implementing additional metal structure on the magnet. The scale is analyzed using axis-symmetric finite element method (FEM). Global optimization is performed using evolution strategy (ES) and then more detailed shape optimization is done using sensitivity analysis. The validity of the proposed design is verified by comparing the magnetic field quantities between conventional and proposed model.
Electromagnetic topology optimization using large-step markov chain method with novel local optimization algorithm
Authors: Im Chang-Hwan , Kim Hong-Kyu , Jung Hyun-Kyo
Published: December 2018

In this paper, a new technique for electromagnetic topology optimization is proposed. The proposed technique is based on the large-step Markov chain (LSMC) method with novel local optimization algorithm. Because the proposed algorithm keeps a good convergence characteristic of LSMC, very fast convergence is assured. The proposed LSMC is verified by an application to an inverse reconstruction problem.
About coupling of domain decomposition methods to a boundary element technique
Authors: Boubendir Yassine
Published: December 2018

A non-overlapping domain decomposition method based on the coupling of a finite-element and boundary-element method is proposed. Several improvements concerning the convergence of the iterative algorithms are given by modifying the transmission conditions at the artificial interfaces between the connected domains.
Application of a superconductor to the shield of a remote field eddy current testing probe
Authors: Yusa Noritaka , Demachi Kazuyuki , Chen Zhenmao
Published: December 2018

This paper proposes the application of a superconductor to a remote field eddy current testing probe in order to shorten the probe length and then overcome many of the disadvantages of the remote field eddy current testing, such as the small signal amplitude and the difficulty in handling the probes. Numerical simulations were carried out to confirm that a superconductor located between the exciter and the detector of a remote field eddy current testing probe inhibits the magnetic flux from coming directly from the exciters. Then, a remote field eddy current testing probe equipped with a superconducting shield was designed and fabricated. Experimental results confirmed that a superconducting shield can shorten the probe length and provide clearer signals due to artificial wall thinnings machined on the outside surface of a ferromagnetic tube.
Power formulation for the optimal control of an industrial induction heating process for thixoforming
Authors: Masserey Alexandre , Rappaz Jacques , Rozsnyo Roland , Touzani Rachid
Published: December 2018

We present an extension of a 2D cartesian electromagnetic and thermal model to achieve the optimal control of an industrial induction heating system. The control variables are the frequency and the power. We explain how to derive the discrete optimal control algorithm and show the numerical results we obtained for a specific case.
Induced voltage analysis of interior permanent magnet motor taking into account Y- or Δ-connected circuit using 3-D finite element method
Authors: Yamaguchi Tadashi , Kawase Yoshihiro , Sano Shinya , Nagai Hidenori , Nakamura Masanori
Published: December 2018

In this paper, we introduce the three-dimensional finite element method (3-D FEM) taking into account the Δ-connected circuit for obtaining the induced voltages of the three-phase motor. We calculate the induced voltage of interior permanent magnet (IPM) motor taking into account the Y- or the Δ-connected circuit of motors using the proposed method. The effects of the connection on the induced voltage are numerically analyzed. The validity of our method is clarified by comparing the calculated results and measured ones.
Magnetic driven valve system and valve timing control mechanism for internal combustion engines
Authors: Nagaya Kosuke , Kobayashi Hiroyuki , Suzuki Takaaki , Koike Kazuya , Takahashi Noriaki , Zhang Xujing
Published: December 2018

A new type driven valve system for combustion engines has been presented, in which a cam is made of permanent magnet, and a roller rocker arm is made of cylindrical permanent magnet. In this system, an attractive force between the cam and the rocker arm due to the magnetic force suppresses jumps and bounces. This makes the friction in the driven valve system decrease. Hence, the resisting torque is decreased by use of this system. This implies that the energy loss decreases. In addition, since the attractive force suppresses the bounce phenomenon, noise due to the bounce is also suppressed in the present system. The analysis for obtaining the critical speed has been presented, and to validate the theoretical results, experimental test has been carried out. In order to have high-energy efficiency, an electric drive valve phase control system is presented. The valve phase control is carried out for the proposed driven valve system by using our control system.
Meshless local Petrov-Galerkin method and its application to electromagnetic field computations
Authors: Ni Guangzheng , Ho S.L. , Yang Shiyou , Ni Peihong
Published: December 2018

A truly meshless local Petrov-Galerkin method to study electromagnetic field problems is introduced with the goal of eliminating the tedious mesh generations required by traditional numerical methods such as Finite Element Methods. The local weighted residual form, together with the penalty approach, is used to develop the discrete mathematical models.
A comparison between parametric and PCA methods of dimension reduction application to an eddy current non destructive evaluation
Authors: Brusquet Laurent Le , Davoust Marie-Eve , Fleury Gilles
Published: December 2018

The remote field eddy current technique is used to inspect conductive pipes and to estimate the dimensions of grooves liable to exist in the conductive material. The problem is to calculate an estimation of groove size from observed data. A two-step inversion is proposed. The first step consists of a reduction of the observed data. For that purpose, a parametric approach and a principal component analysis approach are presented. The second step is based on a polynomial regression and a least square method is used for the two approaches described in the first step. Both approaches are finally compared in terms of precision and robustness.
A 3D stationary Langevin-Lorentz-Poisson model for the analysis of ion transport across cell membranes
Authors: Oliveri Maria E. , Coco Salvatore , Gazzo Daniela S.M. , Giuffrida Cinzia , Laudani Antonino
Published: December 2018

A 3D stationary Langevin-Lorentz-Poisson (LLP) coupled model is presented to investigate the ion transport across excitable cell membranes in the presence of external ELF magnetic field. The strategy proposed is based on an iterative scheme which alternates the solution of a Poisson problem with the time-domain integration of the Langevin-Lorentz equation. A Fokker-Planck analysis of the latter equation is perfomed to compute the statistical parameters of ion motion. This approach has been especially set up in order to take into account explicitly the ion-ion interaction inside ionic channels which has not been considered in literature. The simulations performed show that ELF magnetic field of low intensity (100 μT) can effect significantly the dynamical parameters of ion motion inside the channel provided that the ion-ion interaction is considered.