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A Plan to Reclaim Deuterons Escaping from the Loss Cone of a Magnetic Mirror

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Journal of Modern Physics 2022年第8期13卷 1197-1203页

作者： mitsuaki nagata Soft Creator Company Kyoto Japan

Research on magnetic mirror reactors has had two serious problems since the beginning stage. One is the magnetohydrodynamic instability due to the negative curvature of the magnetic field lines around the center region of a mirror bottle. Another is the loss of charged particles escaping from the loss cone of a magnetic mirror. We have continued to inquire into a means to solve the latter problem. We here propose a new way which will be able to make a magnitude of a loss angle of a magnetic mirror for deuterons virtually zero.

关键词： Magnetic Mirror Control of Escaping Deuterons Plasma Heating by an Extraordinary Wave

Transport of Relativistic Electrons Scattered by the Coulomb Force and a Thermionic Energy Converter with a Built-in Discharge Tube

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Journal of Modern Physics 2021年第12期12卷 1708-1720页

作者： mitsuaki nagata Soft Creator Company Kyoto Japan

A transport equation of momentum for relativistic electrons scattered isotropically was previously reported. Here, a momentum-transport equation for relativistic electrons “scattered anisotropically” by the Coulomb force is inquired into. An ideal plasma consisting of electrons and deuterons is treated again. Also, to raise a generation-ability of a thermionic energy converter, a means of introducing external electric and magnetic fields within “a converter in which an emitter plate and a collector plate face simply each other” is proposed.

关键词： Transport of Relativistic Electrons Coulomb Force Scattering Thermionic Energy Converter with Some Supplemental Equipments

Electron Transport under the Influence of Two Kinds of Friction in an Electron-Deuteron Plasma

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Journal of Modern Physics 2020年第11期11卷 1751-1760页

作者： mitsuaki nagata Soft Creator Company Kyoto Japan

We discuss an electron transport in an ideal plasma which consists of electrons and deuterons. With respect to a frictional force to suppress an unlimited increase of a drift velocity, the Boltzmann equation with the Fokker-Planck collision term takes into consideration only a dynamical frictional force coming from the many-body collisions through the Coulomb force. However, we here bring forward a problem that there may be another frictional force besides the dynamical frictional force. Another frictional force was found in the weakly ionized plasma and appears only in the case where free paths (nearly straight lines in no external force field) can be defined. Then, we have inquired into the existence of physical quantities like free paths (or free times) in the field of the scattering through the Coulomb force and the existence of an effective radius of the Coulomb force of a deuteron.

关键词： Conductivity of Electrons in a Perfectly Ionized Plasma Many-Body and Two-Body Collisions Effective Radius of the Coulomb Force

Control of Deuteron Ions to Escape from the Magnetic Mirror Bottle by a Perpendicular Supplemental Mirror

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Journal of Modern Physics 2019年第11期10卷 1394-1400页

作者： mitsuaki nagata Soft Creator Company Shinmachi Nakagyo-ku Kyoto Japan

We have inquired into a means to decrease the number of charged particles escaping from a loss cone of a magnetic mirror reactor as many as possible. We previously reported the way of installing a supplemental magnetic mirror (which has a cyclotron heating space within) at the exit of a main magnetic bottle. The cyclotron heating space was set to increase a reflection-efficiency of the supplemental mirror. We could not suppress the loss of the escaping deuteron ions sufficiently even with a very long mirror and a very powerful electric field. Then, in this work we propose a new plan of installing another supplemental mirror besides the previous supplemental mirror. A new mirror is set perpendicularly to the center axis of the main bottle. By the addition of the perpendicular mirror, an efficiency of sending back of escaping deuteron ions is considerably theoretically improved. Also in the previous work, since we did not touch how to supply a high-frequency electric field to the cyclotron heating space, here we consider supplying it by an extraordinary-wave with a cyclotron frequency. It is mentioned that propagation of an extraordinary-wave with an electron cyclotron frequency depends on a magnetic field strength and density of escaping electrons.

关键词： Magnetic Mirror Reactor Control of Escaping Deuteron Ions Electron and Deuteron Ion Heating by Extraordinary Waves

Further Improvement of Reflection Efficiency of a Magnetic Mirror and Replenishment against Loss of Escaping Deuteron Ions

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Journal of Modern Physics 2019年第2期10卷 145-156页

作者： mitsuaki nagata Keiichi Sawada Soft Creator Company Kyoto Japan

We reported previously the idea to improve reflection-ability of a magnetic mirror by installing a cyclotron resonance space in the front part of the mirror. However, since the previous analysis was insufficient from the examination after that, we complement the following two things in this work: 1) A simpler procedure of design to make a supplemental magnetic mirror with the simplest magnetic configuration, compared with the procedure reported previously. 2) A peculiar characteristic arising only in reflection of a nonrelativistic charged particle (a deuteron ion).

关键词： Magnetic Mirror Cyclotron Resonance Heating Reflection and Replenishment of Deuteron Ions

Bell Operator Method to Classify Local Realistic Theories

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Chinese Physics Letters 2010年第3期27卷 29-32页

作者： Koji nagata Department of Agriculture and of Veterinary Medicine National Research Center for Protozoan Diseases University of Obihiro West 2-13 Inada Obihiro Hokkaido 080-8555 Japan

We review the historical fact of multipartite Bell inequalities with an arbitrary number of settings. An explicit local realistic model for the values of a correlation function, given in a two-setting Bell experiment （two-setting model）, works only for the specific set of settings in the given experiment, but cannot construct a local realistic model for the values of a correlation function, given in a continuous-infinite settings Bell experiment （infinite-setting model）, even though there exist two-setting models for all directions in space. Hence, the two-setting model does not have the property that the infinite-setting model has. Here, we show that an explicit two-setting model cannot construct a local realistic model for the values of a correlation function, given in an M-setting Bell experiment （M-setting model）, even though there exist two-setting models for the M measurement directions chosen in the given M-setting experiment. Hence, the two-setting model does not have the property that the M-setting model has.

关键词： Quantum information and quantum mechanics

Advances in traction methods for endoscopic submucosal dissection:What is the best traction method and traction direction?

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World Journal of Gastroenterology 2022年第1期28卷 1-22页

作者： Mitsuru nagata Department of Endoscopy Shonan Fujisawa Tokushukai HospitalKanagawa 251-0041Japan

Endoscopic submucosal dissection(ESD)has been developed as a treatment for superficial gastrointestinal neoplasms,which can achieve en bloc resection regardless of the lesion ***,ESD is technically difficult because endoscopists cannot bring their hand into the gastrointestinal tract,unlike surgeons in regular *** is difficult to obtain sufficient tension in the dissection plane and a good field of ***,ESD is associated with a long procedure time and a high risk of adverse events in comparison with endoscopic mucosal *** methods have been developed to provide sufficient tension for the dissection plane and a good field of vision during the ESD ***,traction direction is limited in most traction methods,resulting in insufficient effect in some *** traction direction is considered important,there have been few investigations of its *** the first half of this review,important traction methods are discussed,including traction *** second half,appropriate traction methods for each organ are *** important considerations for traction method,such as ability to adjust traction strength,interference between traction device and endoscope,and the need for specialized devices are also discussed.

关键词： Endoscopic submucosal dissection Traction method Countertraction Traction direction Vertical traction

Experimental Study on Load Characteristics in a Floating Type Pendulum Wave Energy Converter

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Journal of Thermal Science 2014年第5期23卷 465-471页

作者： Tengen Murakami Yasutaka Imai Shuichi nagata Institute of Ocean Energy Saga University

A floating type pendulum wave energy converter(FPWEC) with a rotary vane pump as the power take-off system was proposed by Watabe et *** *** showed that this device had high energy conversion *** the previous research,the authors conducted 2D wave tank tests in regular waves to evaluate the generating efficiency of FPWEC with a power take-off system composed of pulleys,belts and a *** a result,the influence of the electrical load on the generating efficiency was ***,the load characteristics of FPWEC are pursued experimentally by using the servo motors to change the damping coefficient in this *** a later part of this paper,the motions of the model with the servo motors are compared with that of the case with the same power take-off system as the previous *** the above experiment,it may be concluded that the maximum primary conversion efficiency is achieved as high as 98%at the optimal load.

关键词： pendulum wave energy converter floating type load characteristics primary conversion efficiency

Adaptive Learning with Large Variability of Teaching Signals for Neural Networks and Its Application to Motion Control of an Industrial Robot

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International Journal of Automation and computing 2011年第1期8卷 54-61页

作者： Fusaomi nagata Keigo Watanabe Department of Mechanical Engineering Faculty of Engineering Tokyo University of Science Department of Intelligent Mechanical Systems Graduate School of Natural Science and Technology Okayama University

Recently, various control methods represented by proportional-integral-derivative （PID） control are used for robotic control. To cope with the requirements for high response and precision, advanced feedforward controllers such as gravity compensator, Coriolis/centrifugal force compensator and friction compensators have been built in the controller. Generally, it causes heavy computational load when calculating the compensating value within a short sampling period. In this paper, integrated recurrent neural networks are applied as a feedforward controller for PUMA560 manipulator. The feedforward controller works instead of gravity and Coriolis/centrifugal force compensators. In the learning process of the neural network by using back propagation algorithm, the learning coefficient and gain of sigmoid function are tuned intuitively and empirically according to teaching signals. The tuning is complicated because it is being conducted by trial and error. Especially, when the scale of teaching signal is large, the problem becomes crucial. To cope with the problem which concerns the learning performance, a simple and adaptive learning technique for large scale teaching signals is proposed. The learning techniques and control effectiveness are evaluated through simulations using the dynamic model of PUMA560 manipulator.

关键词： Neural networks large-scale teaching signal sigmoid function adaptive learning servo system PUMA560 manipulator trajectory following control nonlinear control.