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Universities in Japan are putting efforts into establishing international academic agreements, as they recognize the benefits that these partnerships can bring in terms of research, academic exchange, and cultural understanding. This paper aims to show the current situation of international academic exchange agreements at Tokushima University (TU) in the context of Japan’s higher education. From the situation, breakdown, trends, and challenges of TU’s international partnerships over the years, the authors show their perspectives on the vital importance of agreements are a keyway to collaborating, sharing resources, creating opportunities, promoting global understanding, and preparing students for a world where cross-cultural and international collaboration is becoming increasingly important.

The intensity and energy spatial distributions of collimated laser Compton scattering (LCS) $\gamma$-ray beams and of the associated bremsstrahlung beams have been investigated as functions of the electron beam energy, electron beam phase space distribution, laser optics conditions and laser polarization. We show that the beam halo is affected to different extents by variations in the above listed parameters. In the present work, we have used laser Compton scattering simulations performed with the \texttt{eliLaBr} code (https://github.com/dan-mihai-filipescu/eliLaBr) and real LCS and bremsstrahlung $\gamma$-ray beams produced at the NewSUBARU synchrotron radiation facility. A 500~$\mu$m MiniPIX X-ray camera was used as beamspot monitor in a wide $\gamma$-ray beam energy range between 1.73~MeV and 38.1~MeV.

The intensity and energy spatial distributions of collimated laser Compton scattering (LCS) $γ$-ray beams and of the associated bremsstrahlung beams have been investigated as functions of the electron beam energy, electron beam phase space distribution, laser optics conditions and laser polarization. We show that the beam halo is affected to different extents by variations in the above listed parameters. In the present work, we have used laser Compton scattering simulations performed with the \texttt{eliLaBr} code (https://github.com/dan-mihai-filipescu/eliLaBr) and real LCS and bremsstrahlung $γ$-ray beams produced at the NewSUBARU synchrotron radiation facility. A 500~$μ$m MiniPIX X-ray camera was used as beamspot monitor in a wide $γ$-ray beam energy range between 1.73~MeV and 38.1~MeV.

This work shows the lessons learned from the online course on Basic Medical Japanese for international students conducted between May and July 2020 at Tokushima University. The participants were five graduate students from China, Bangladesh, Thailand, including one male and four females. This course was designed for the learners to master basic medical terms and phrases in Japanese, as well as to be able to make basic conversation in health care context. The course materials were prepared bilingually, consisted of 13 lessons covering practical topics such as “parts of human body”, “basic symptoms”, “medicines and drug store”, “respiratory system”. For each lesson, the learners were introduced to new vocabulary and basic expressions by doing role play, translating sentences, solving quiz, and watching clips. The results of class assessments and end-course assessment had shown improvements of vocabulary capacity and context-based conversation skills for most of the topics. However, the learners showed difficulties in learning topics with more complicated terminology such as “psychiatry”. The learners reported that besides improving their medical Japanese language skills, they had gained more confidence in using Japanese for medical purposes, as well gained motivation for mastering medical Japanese. They found visual aids and English instruction were helpful to absorb the content. These results imply that teaching Japanese for medical purpose may contribute to improving practical Japanese skill and confidence in daily life for international students in Japan.

Intense, quasi-monochromatic, polarized $γ$-ray beams produced by Compton scattering of laser photons against relativistic electrons are used for fundamental studies and applications. Following a series of photoneutron cross section measurements in the Giant Dipole Resonance energy region performed at the NewSUBARU synchrotron radiation facility, we have developed the eliLaBr Monte Carlo simulation code for characterization of the scattered $γ$-ray photon beams. The code is implemented using Geant4 and is available on the GitHub repository (https://github.com/dan-mihai-filipescu/eliLaBr). Here we report the validation of the eliLaBr code on NewSUBARU LCS $γ$-ray beam flux and spectral distribution data and two applications performed with it for asymmetric transverse emittance profiles electron beams, characteristic for synchrotrons. The first application is based on a systematic investigation of transverse collimator offsets relative to the laser and electron beam axis. We show that the maximum energy of the LCS $γ$-ray beam is altered by vertical collimator offsets, where the edge shifts towards lower energies with the increase in the offset. Secondly, using the eliLaBr code, we investigate the effect of the laser polarization plane orientation on the properties of the LCS $γ$-ray beams produced with asymmetric emittance electron beams. We show that: 1. The use of vertically polarized lasers contributes to the preservation of the LCS $γ$-ray beam maximum energy edge by increasing the precision in the vertical collimator alignment. 2. Under identical conditions for the electron and laser beams phase-space distributions, the energy spectrum of the scattered LCS $γ$-ray beam changes with the laser beam polarization plane orientation: the use of vertically polarized laser beams slightly deteriorates the LCS $γ$-ray beam energy resolution.

The monophyly of the tribe Trichopterygini is considered. The currently used Trichopterygini are polyphyletic. Thepresent Trichopterygini are defined by the following autapomorphies: the enlarged metepimeron in both sexes and a pair of triangularexpansions on the male abdominal sternum II, and are redescribed mainly based on adult characters. Phylogenetic relationshipsamong the Japanese genera are analyzed cladistically with the inclusion of two European, three Oriental, and one New Zealandgenera. Japanese Trichopterygini are composed of 15 genera, of which two are new, one is upgraded from a subgeneric rank, and oneis synonymized: Pseudacasis gen. nov., Paratrichopteryx gen. nov., Paralobophora Inoue (upgraded), Lobophorodes Hampson (asenior synonym of Epilobophora Inoue), Lobophora Curtis, Neopachrophilla Inoue, Phthonoloba Warren, Trichopterigia Hampson,Acasis Duponchel, Otoplecta Warren, Esakiopteryx Inoue, Cladara Hulst, Trichopteryx Hübner, Episteira Warren, and Sauris Guenée.Except for Phthonoloba and Lobophorodes, the Japanese genera are classified into four genus-groups: 1, Lobophora genus-groupconsisting of Lobophora and Neopachrophilla; 2, Trichopteryx genus-group consisting of Cladara, Esakiopteryx, Paralobophora,Paratrichopteryx and Trichopteryx; 3, Acasis genus-group consisting of Acasis, Otoplecta, Pseudacasis and Trichopterigia; 4, Sauris genus-group consisting of Episteira and Sauris. The Japanese genera are also redescribed mainly by the adult characters and a key to them is provided. Brief information on morphology, bionomics, and distribution of the Japanese species are also given together with their genital figures. Two Trichopteryx species, T. miracula Inoue and T. muscigera (Butler), are transferred to the genus Cladara. A new tribe Heterophlebini is established for the genera Carige Walker, Heterophleps Herrich-Schäffer, Naxidia Hampson, Palaeomystis Warren and their relatives. http://zoobank.org/.../726a6c43-3e72-4b9f-b367-27db1aef27e3

A compact and low-cost 1 GeV injector linac was designed and constructed to provide injection beams to the soft X-ray synchrotron radiation facility NewSUBARU instead of the SPring-8 injector system, which will be shutdown. The total length of the injector linac needs to be less than 70 m to fit into the existing tunnel. To this end, an RF electron gun with a gridded thermionic cathode directly attached to a 238 MHz RF cavity was developed and adopted. The 500 keV, 0.6 ns, 1 nC beam emitted from the cavity is compressed to 3 ps by velocity bunching driven by a 476 MHz RF cavity and a S-band RF structure. The short-pulsed beams are accelerated up to 1 GeV with 16 C-band RF structures. In the C-band accelerator section, the klystron output of 50 MW is multiplied 4 times by a pulse compressor and fed to the 4 RF structures to generate a high accelerating field of 31 MV/m. A low-level RF system consisting of a MTCA.4 based high-speed digitizers and RF frontend boards has been constructed. This injector system is used at the 3 GeV SR facility currently under construction in Sendai. In this paper, we report the design outline and the operational performance of the injector system., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

This paper proposes an anomaly detection method for the prevention of industrial accidents using machine learning technology.

In fair weather, a clear diurnal variation of atmospheric electric field (AEF), which is distinctly different from the global diurnal variation, i.e., Carnegie curve, was observed during the summer time (July and August) of the year 2010 and 2011 at the summit of Mount Fuji, Japan (3776 m in altitude). The variation of the AEF at the summit showed a local time dependent feature, which means that the AEF increased at sunrise and decreased at sunset. This local diurnal variation is known as a mountain variation. The intensity of AEF in the daytime reached 1.5–3 times larger than that in the nighttime. From the multipoint observations of cloud images and AEF, the mountain variation was found to be attributable to the AEF generated by the positively charged top of a horizontally extensive sea of clouds below the summit. Since the sea of clouds grows with the temperature rise, the AEF variation follows local time.

We have proposed a new selective isotope transmutation method using photonuclear reactions with quasi-monochromatic gamma-ray beams. This method is based on the fact that the particle threshold of a long-lived fission product (LLFP) such as 93Zr, 107Pd, or 79Se is lower than those of stable isotopes of the same chemical element. Therefore, this method has the excellent advantage that LLFPs cannot, in principle, be produced newly even if the target materials include stable isotopes in addition to LLFPs. Furthermore, this method is effective for 126Sn, 135;137Cs, 90Sr, and 3H. The nuclear data involved and suitable gamma-ray sources are discussed. Laser Compton scattering gamma-ray sources and neutron capture gamma-rays in nuclear reactors are candidates for this method.

Strawson argues that there is another way with scepticism which is not an attempt directly to refute it by rational argument drawing on commonsense or theological or quasi-scientific considerations. Vis-à-vis traditional scepticism he proposes the naturalist position. He considers a response which dose not so much attempt to meet the challenge as to pass it by. In characterizing the position he yokes Wittgenstein to Hume. In his naturalism Strawson dose not examine the reason for the certainty with 'unshakeable thing', but argues only the causes of them. According to Wittgenstein, certainty belongs to 'unshakeable thing' that underlies all our ordinary language-games. In the entire system of our language-games 'unshakeable thing' belongs to the foundation of it and the whole language-games rests on this kind of certainty. Ordinary language-games such as about knowledge, doubt, belief, etc. make sense only when our language-game has 'unshakeable thing' as foundation. The status of 'unshakeable things' can be conceived as propositions of grammar; in the system of our empirical propositions they have a peculiar logical role, that is, they have the character of a rule. Strawson fails to grasp the point of view about the system of our language-games.

The oxygen diffusivity of hexagonal barium titanate by the tracer method and its dielectric constants have been evaluated. The oxygen diffusivity of hexagonal barium titanate does not show any direction dependency along [0001] and [1000] directions in lattice. Because of the face-shared position is more favorable position of oxygen vacancy than the corner-shared position. The dielectric constant along [1000] direction is larger than the [0001] direction. The difference of dielectric constant between both directions was gradually decreased with increasing the annealing temperature owing to reduction of the oxygen vacancies.

Although the hexagonal barium titanate has been widely studied, the oxygen diffusivity has not been yet. The oxygen diffusivity is very important property, because the electrical properties are dominated by the amount of oxygen vacancy and the diffusivity. In this study, it is measured the diffusivity of oxygen by the tracer method and its activation energy was obtained from the Arrhenius plot. The oxygen diffusivity of hexagonal barium titanate is smaller than the cubic one and its activation energy, 1.73 eV is also smaller. Because of the formation energy of oxygen vacancy in the hexagonal structure is 0.884eV smaller than the cubic structure. These are depended on the distance of nearest O-O bonding, respectively. The formation energies were calculated by the first principle calculation using VASP code.

大気球シンポジウム 平成21年度 (2009年10月1-2日. 宇宙航空研究開発機構宇宙科学研究本部), 相模原, 神奈川, Balloon Symposium 2008 (October 1-2, 2009. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)), Sagamihara, Kanagawa Japan, 資料番号: AA0064736007

大気球シンポジウム 平成23年度（2011年10月6-7日. 宇宙航空研究開発機構宇宙科学研究所 (JAXA)(ISAS)）, 相模原市, 神奈川県), Balloon Symposium 2011 (October 6-7, 2011. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000067032, レポート番号: isas11-sbs-032

The periodic fluctuations and drifts in the radiation intensity have been observed at the NewSUBARU synchrotron radiation facility. To clarify the cause of this problem we have measured temperatures of air, cooling water, equipments and building with the network-distributed data logger. And we found that temperature fluctuations in both air in the shielded tunnel and the cooling water mainly affect the stabilities of electron beam orbit and optical axis. To maintain a constant temperature, the large doors for carrying equipment at the experimental hall were covered with insulated curtains, and we optimized PID parameters of temperature controllers for air and water. As results, the periodic fluctuations almost disappeared, but some drifts were still remained, which are due to slow variations of equipment temperature. By realizing the automatic COD correction, the drift in electron beam position could be suppressed and the fluctuations of radiation intensity observed at beam-lines became smaller than they used to be. For further stabilization, we recently introduced a XBPM upstream in a beamline to measure the vertical position of radiation axis precisely., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

Transverse beam instabilities were suppressed with chromaticity modulation (CM)* in the electron storage ring, New SUBARU. The horizontal and vertical betatron tune spread inside a bunch were introduced by CM with synchrotron oscillation frequency driven by an AC sextuple magnet**, to obtain Landau damping of the coherent bunch motion. The tune spread in a bunch is usually introduced by octupole field, however, its high nonlinearity reduces the dynamic aperture. And usual feedback against instabilities work only on m=0 mode and it is not easy to be applied to hadron synchrotrons because of their varying revolution period. The CM scheme has not such disadvantages. The damping time of coherent motion excited by external kick was measured and was found as less than 1ms, one order faster than that without CM. To observe the effect on instabilities, we intentionally tuned an HOM in a cavity to excite a horizontal multi-bunch instability. The instability peak in the spectrum of the beam motion was vanished with CM turned on and the instability was suppressed. We also observed the increase of the threshold current of the vertical single-bunch mode-coupling instability by factor 3 with CM., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The intergranular corrosion in stabilized 310 stainless steel polycrystals has been investigated from a view point of crystallographic structure of the grain boundary. The relative orientation of each grain was characterized by the Coincidence Site Lattice (CLS) model, and the Plane Matching model. For the quantitative characterization of corrosion, a scanning electron microscope with two secondary electron detectors was used to provide the profile of the corrosion groove. It was found that Σ= 3 boundaries and some certain CSL boundaries have a high resistance against the intergranular corrosion. The “random” boundaries were corroded in a different extent, particularly high corrosivity. It is concluded that the grain boundaries having low Σ-values do not necessarily provide low corrosivity. It is shown that the dissolution rate depending on the surface orientation of grains also plays an important role in the morphology of intergranular corrosion, and was found to be lowest at (100) and increases as the surface normal changes towards (110), and more so towards (111).

特集 = Special Feature

制度:新 ; 文部省報告番号:甲1507号 ; 学位の種類:博士(理学) ; 授与年月日:2001-02-08 ; 早大学位記番号:新3079 ; 理工学図書館請求番号:2530

The existence and nonexistence of positive classical solutions is discussed for $-\Delta u = K(x) (1-|x|)^{- \alpha} u^{\beta}$ in the unit ball $B$ with Dirichlet boundary condition ${u |_{\partial B}= 0 }$. Our main tools are based on the variational method and Pohozaev's identity. The singularity of coefficients on the boundary will be handled with the symmetry of functions and some approximation procedures.

Crystal structures of the Al-Ti, Al-Hf, Ga-Ti and Ca-Zr alloys in the composition range from A_3B to A_2B were studied by electron diffraction. It was confirmed that the D0_22 structure exists in the Al-Ti and Ga-Ti systems and the D0_ in the Al-Hf and Ga-Zr. In addition, long-period one-dimensional antiphase domain structures (ld-APS) with average domain sizes of non-integer (M) times the basic Ll_2 cell were found to exist in the Al-Ti and Al-Hf systems ; the ld-APS with M=1.33 and the ld-APS's with M=1.60-1.91 were found in the specimens containing 26.5-32.5 at.% Ti, and the ld-APS with M=1.31 was found in the specimens with 29-31.5 at.% Hf.

It is known that at room temperature the tensile stress-strain curve of an aluminum single having tensile orientation becomes flat after about a two percent elongation. (This flat region of the stress-strain curve is named Stage IV). In the previous paper, the propagation of a clustered slip accompanied by a prominent cross slip was observed in the Stage IV region of curve. In the present study, oriented aluminum single crystals were tested in tension at various temperatures so as to clarify the influence of temperature on the deformation mechanisms in Stage IV. At 203K, a few clustered slip lines accompanied by a prominent cross slip occurred, but they did not propagate in the entire region of the specimen. The stress-strain curve became flat only from about a ten percent elongation. In the crystal stretched at 77K, the cluster did not propagate at all from either end of the specimen, and so the stress-strain curve did not become flat. On the other hand, a wavy coarse slip was observed and the curve became flat from about a 0.5 percent elongation at 473K. It was suggested that these wavy slip lines were produced by a frequent repetition of the cross slip on two {111} planes and also possidly on a {110} plane having the same slip direction. It was confirmed that the occurrence of Stage IV is caused by the of the clustered slip accompanied by a prominent cross slip, and is much influenced by the temperature of deformation due to the easiness of the cross slip.

In order to investigate the characteristics of the P-L effect and to obtain additional information on the production of vacancies during tensile and fatigue deformation, tensile and tension-compression tests were performed in Ag-6.3 at.% Al and α-brass polycrystals. It was found that the P-L effect in Ag-Al alloy is well explained by the dynamic strain aging model by Cottrell. The effective activation energy for the migration of a vacancy in Ag-Al alloy is estimated to be 0.6±0.02eV. It was also confirmed, from the experiment of annealing the excess vacancies, that the P-L effect is strongly affected by the accumulation of vacancies produced by strain. The strain exponent m, of a vacancy concentration produced by strain, was determined to be m＝1.35. This is equal to that obtained from the static strain aging experiment, assuming the strain exponent of total dislocation density to be β＝1. In the cyclic straining conducted under the prescribed strain amplitude, the cumulative strain to the onset of the P-L effect is greater for a lower strain amplitude. However, the values subtracted by the sum of a Bauschinger strain β₁ in each half cycle from the cumulative strains give an approximately constant value independent of the magnitude of the strain amplitude. The values are larger than the critical strain for the onset of the P-L effect in unidirectional deformation by an amount of 20% in both alloys. From the results, it can be concluded that vacancies are produced only in the complete plastic strain region subsequent to the Bauschinger strain β₁ during cyclic straining. Hence, the efficiency of the vacancy production would decrease with an increase in the number of cycles. Namely, the saturation of the vacancy production is to be directly correlated to the saturation of the cyclic strain hardening. Furthermore, it is suggested that the efficiency of the vacancy production during the cyclic straining is lower by 20%, even in the complete plastic strain region, probably because of the vacancy-interstitial annililation.

Dislocation arrays in lightly deformed Cu-9 at.% Al bicrystals, whose component crystals have a crystallographic mirror symmetry with respect to the grain boundary, are observed by the etch-pitting technique. Then, the influence of the grain boundary on the Bauschinger effect is discussed. It is shown that the induced secondary slips near the boundary can be explained quantitatively in terms of stress concentration due to the piled-up dislocations of adjacent crystal. Some of them can be also explained by the microscopic incompatibility owing to the mismatch of primary slip bands in each component crystal at the boundary. From the observations of reversed bicrystals, it becomes evident that the induced secondary disloca tions near the boundary, which exist mostly by forming double ended pile-ups between the primary slip bands, are unstable against reverse stress. Namely, most of them are annihilated in the first stage of reverse stressing, and are subsequently recovered by a further reverse stress. It is pointed out that although primary dislocations near the boundary can move even a small reverse stress backwards by the aid of high back stress on dislocations because of the latent hardening by multiple slips and pile-up dislocations, the mean free path of the primary dislocations is thought to be small due to the interference of secondary dislocations. Consequently, the Bauschinger effect in a multiple slip layer is presumably smaller than that in the center of each component crystal.

With a view of solving the cause and essence of the Bauschinger effect, dislocation behaviour under reverse stress has been investigated in Cu-9at% Al alloy single crystals, using an etch-pitting technique. From the direct measurements of the beginnings of backward movements of dislocations, the frictional resistance force to moving dislocations due to solid solution hardening is estimated to be approximately 0.8kg/㎟, which is ≃4/5 of easy glide stress. It is found that pile-up dislocations against a barrier move well under the reverse stress range from 0.6 to 0.7 to the pre-stress level, but then hardly move more than the reverse stress ratio of 0.8. Evidence of almost complete annihilation of double ended pile-ups which are generated by the same source is presented. Another striking evidence of radical annihilation of dislocations within uniformly aligned dislocation groups of the same sign is also discovered. Mechanisms acceptable for explaining such results are proposed respectively, i.e., the mutual annihilation of dislocations of opposite signs, and the double cross-slip mechanism. It is suggested that the characteristics of rearrangements of dislocations against stress reversal are probably connected with the latter mechanism, which would be responsible for cyclic strain hardening.

Two sorts of Cu-Zn-Si pseudo-elastic bicrystals of shape memory alloy were tested in tension to know the effects of the grain boundary. The remaining martensites were observed in the vicinity of the grain boundary, and the propriety of analyses through use of m/m。 and Nᵢj values and of the compatibility of the plastic strain were studied. The variant of martensite occurring primarily in each grain during deformation, can be predicted with use of them value (shear factor of the variant) in general. The analyses through use of m/mᵢ and Nᵢj values and the equations of the plastic strain compatibility are sufficiently useful to know the variant of martensite nucleated additionally in the vicinity of the grain boundary. However, the possibility of activation of slip must be considered in this case. The reversible strain of the isoaxial bicrystal is larger than that of the non-isoaxial bicrystal. However, the relation between the reversible strain and the misorientation of bicrystal is not yet sufficiently known.

It is known that an aluminum single crystal having tensile orientation shows an initial rapid hardening, and that its flow stress increases gradually until failure. However, many problems pertaining to the deformation mechanism of the oriented single crystal remain unsolved. In the present study, to clarify the deformation mode of aluminum single crystals having multiple slip orientations, tensile test were performed at various temperatures on oriented single crystals. At room temperature, the oriented single crystal deformed only by fine multiple slips, and the flow stress increased with an increase of strain until failure. On the other hand, the coarse wavy slips composed of {111} and {100} slips occurred at high temperatures, such as 473K. In the single crystal having a tensile orientation deviated from by a few degrees, the clustered slips were observed in addition to the fine multiple slips. It is concluded that the deformation mode and flow stress of the single crystal are very sensitive to the tensile oriention in the vicinity of .

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