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Superposition of Ornstein–Uhlenbeck processes, called supOU process, is an integration of (infinitely) many OU processes via Lévy bases. We present its Monte–Carlo method (MCM) based on the Markovian lift to efficiently handle the infinite-dimensional nature by a finite-dimensional truncation. In this method, the supOU process is discretized in time using an existing explicit scheme, while in the phase space by a quantile discretization. Numerical experiments are carried out to evaluate the performance of the MCM and to compare it with a Fourier inversion method. [ABSTRACT FROM AUTHOR]

Injection overmolding process is promising process for fabrication of thermoplastic composites which has excellent mechanical properties and complex shapes. Concretely, the continuous fiber-reinforced thermoplastic composites are fabricated by stamping process as substrate. Followed by the melt polymer is overmolded onto the substrate by injection molding for fabrication the ribs and bosses. Therefore, in this process, joining strength between two materials is a major factor in the mechanical strength of a product. As the new approach to improve the joining strength, nanofiber-filled thermoplastic film is inserted between the substrate and overmolded polymer for reinforcing the interface directly in nanoscale. In our previous works, we revealed that multi-walled carbon nanotubes (MWCNTs) filled polypropylene (PP) films could improve the interlaminar shear strength. However, it is still unclear cause why interlaminar shear strength increased by adding the films. In this study, to clarify the influence of nanofiller size on the adhesion strength, two kinds of nanofillers, CNTs and vapor grown carbon fibers (VGCFs) were used. As a quantitative evaluation method of adhesive strength, a tensile overlay shear strength test was performed. As a result, it improved the joining strength at CNT contents of 0.5wt% of CNTs film the best. CT scan images confirmed that CNT tangled with polymer chains. This indicated that entanglement between CNTs and injection resin has effect on the adhesion. By diffraction scanning calorimetry (DSC) data, the crystallinity of nanofiller-filled thermoplastic film was lower than PP film and it was considered that addition of nanofiller distracted crystallization PP. Therefore, although the crystallinity of substrate surface decreased by adding nanofibers, CNT contents of 0.5wt% was the best contents for joining strength. Consequently, the relationship between crystallinity and joining strength requires detailed investigation, such as focusing on crystallization behavior during cooling. [ABSTRACT FROM AUTHOR]

Since the increasingly high spread of coronavirus (Covid-19), the government decided to implement the Work From Home (WFH) system. It certainly changes the pattern of daily activities at home, which initially may only consider the house as a place to rest, but now have to do various activities at home. In response to this, the demand for space requirements indeed becomes drastically increased because there are many adjustments needed in daily activities. Besides, space requirements are not the only priority, but the application of design to the Covid-19 response is also needed, such as creating good air circulation and natural lighting in a building. Therefore, this study aims to meet the needs of occupants by prioritizing comfort while producing a good building design taking into account the current Covid-19 pandemic. This journal used qualitative research methodology, which includes; Re-planning the spatial and zoning program of the house based on the activities of the occupants; Interviewing the occupants related to the changes of the clinic during Covid-19; The implementation of several factors to prevent Covid-19, namely in terms of layout and circulation, ventilation and lighting, material, infrastructure, and structure; Final design results. In conclusion, this study aims to fulfill the activities of occupants during the COVID-19 pandemic with the methods applied. [ABSTRACT FROM AUTHOR]

Numerical simulations for seismic loading analysis require data on the material properties of the element under investigation. This study presents a method for estimating the combined hardening parameters for structural steel with various grades based on available cyclic hysteresis data. Voce isotropic hardening and Chaboche kinematic hardening were selected to reflect the cyclic characteristics of various structural steels. A numerical analysis with the obtained combined hardening parameters generates good results data for a wide range of material properties for structural steels with different yield ratios. Based on the obtained parameters, some simple equations that describe the correlation between the combined hardening model and material properties such as the yield ratio are derived. [ABSTRACT FROM AUTHOR]

The 2-dimensional local inertial equations (20 LIE), a computationally efficient approximation of the shallow water equations, has been applied to surface water flow simulation in Tonle Sap Lake (TSL), Cambodia. Focusing on the unique characteristic that the lake flow is dominated by the mainstream of the Mekong River, this study examined the predictability of the water stage TSL from the fixed-point observation data at the Prek Kdam station (PK) (boundary between the Mekong and Tonle Sap Rivers). Considering the fact that flood pulse propagates from PK to TSL, the lag time map showing the delay of flood pulse at each computational mesh of 20 LIE was created. As the result, the lake water stage in the wet season (August to October) mostly corresponds to that at PK with the delay of 3 to 5 days whereas the delay becomes longer (15 to 18 days) in the dry season (February to April) due to smaller flow velocities. Even in the dry season, the RMSE of the estimated water stage is less than 0.5 m in the lake. The result indicated the potential of real time prediction of the lake water stage using the fixed-point observation and the lag time map. [ABSTRACT FROM AUTHOR]

Brilliant synchrotron radiation (SR) has enabled us to investigate fast phenomena even in small samples. At the same instance, the property of sample may be affected by the SR due to the high brilliance. An SR X-ray pump and optical probe measurement has then been performed at a storage ring facility of SPring-8 to investigate the spectral change in the near infrared region of a GaAs single crystal irradiated by an intense X-ray pulsed SR beam with a photon energy of just above the K-edge of As. The transient transmission spectrum was monitored by using a broadband optical pulsed beam and a dispersive spectrometer. We obtained the spectral profile change with a response time of shorter than the pulse duration of SR. The spectrum shows the abrupt change in transmittance at around 880 nm corresponding to the band gap energy of GaAs, and the fringe on the spectrum originated from the interference at the sample with a thickness of about 10μm. The band gap energy and the fringe shift to the opposite direction to each other, the behavior of which is explained to be due to the band gap shrinkage accompanied with the decrease of refraction index originated from the free carriers. The transient band gap shrinkage suggests the nonthermal lattice distortion induced by SR irradiation. [ABSTRACT FROM AUTHOR]

The Asian Nuclear Physics Association (ANPhA) is the central organization representing nuclear physics community in Asia Pacific. ANPhA is now preparing a list of accelerators applicable for nuclear physics experiments in Asia Pacific. Among the listed facilities, world-class "major" accelerator facilities are mainly located in China (Heavy Ion Research Facility in Lanzhou (HIRFL), and its future extension in Huizhou, i.e. HIAF/CiADS, Beijing Tandem Accelerator National Laboratory (BTANL), which is now upgraded to Beijing RI beam Facility (BRIF)), in Korea (RISP/RAON), and in Japan (RIBF at RIKEN, J-PARC, RCNP, and ELPH/LEPS). Characteristics of these "major" facilities including their developments will be briefly reviewed in comparing with similar ones in Europe and North America. [ABSTRACT FROM AUTHOR]

In order to clarify the repulsive vacancy interaction which has been predicted for tungsten in recent theoretical studies, recovery behaviors of electron-irradiation-induced vacancies in high-purity tungsten (99.999 wt%) and tantalum (99.95 wt%) samples were investigated by using positron annihilation lifetime spectroscopy. As a result, attractive interactions between vacancies were observed in both samples. However, since the presence of vacancy-impurity complexes was suggested even in the high-purity tungsten, such impurities might have affected the recovery behavior of vacancies. [ABSTRACT FROM AUTHOR]

In this study, thermal induced flow around a set of thin discs with slits in a straight pipe was investigated using the direct simulation Monte Carlo DSMC method. The surface temperature of one side of each disc was set higher than that of the other side, with the temperature ratio between high and low temperature surfaces (TH/TL) set equal to 1.05. The simulation showed that the pressure rapidly increases before and after the disc, suggesting that the thin disc plays the role of a pump by generating thermal induced flow around the slits in each thin disc. [ABSTRACT FROM AUTHOR]

This study discusses the use of HC-290 with 95.5% propane content as a safe and energy-efficient alternative for retrofitting of R22. The set-up equipment consists of a compressor, condenser, evaporator and capillary tube. The system test is performed using a variation of evaporator entrance temperature as the cooling load. Temperatures were varied 20°C, 23°C, 25°C, 29°C, respectively. The small wall room air conditioner was charged by R22 according to the nameplate and R-290 with a variation of 30%, 40%, 50% and 60% of total mass according to the nameplate. R290 has a higher refrigeration effect than R22. But R22 has cooling capacity higher than R290. The highest electrical consumption was the air conditioner, which was charged by R22 and was followed by propane 95.5% with 60%, 50%, 40% and 30% charging. The average electrical consumption of the air conditioner charged by R22 was 1.5 times the air conditioner to be charged by R290. The highest COP was obtained by propane 95.5% with 60% charging and followed by R22. While propane 95% with 30%, 40%, and 50% charging had low COP. [ABSTRACT FROM AUTHOR]

X-ray diffraction with anomalous scattering (anomalous diffraction) is an effective method to distinguish the positions of atoms which have similar number of electrons in crystal structure. We have been developing a method for anomalous powder X-ray diffraction with synchrotron X-ray by the combination of focused beam, flat sample and area detector and succeeded in the determination of the distribution of cations with neighboring atomic numbers. This method can be applied to analysis of the position of ions with different valence of an atom in crystal structure, therefore we have tried anomalous powder X-ray diffraction experiments of materials that include different valence ions of an atom. LiMn2O4 was an example of such material. In the crystal structure, a normal spinel, the Mn atoms in octahedral site takes mixed valence state of Mn3+ and Mn4+. This material has a phase transition near room temperature and below the phase transition temperature a structure with partial ordering of Mn3+ and Mn4+ has been proposed. In order to examine anomalous scattering effect of Mn3+ and Mn4+, diffraction experiments using X-rays near Mn K edge were conducted. The result of diffraction experiments shows that the diffraction peak intensity change depend on the incident X-ray energy in different manner peak by peak. Powder diffraction data that include anomalous scattering effect can be successfully obtained from material with mixed valence state of Mn3+ and Mn4+. [ABSTRACT FROM AUTHOR]

This paper discusses two issues relating to using 3 small gap insertion devices in series at BL43LXU of SPring-8 to make a uniquely powerful source in the 15-26 keV region of the x-ray spectrum. The issues discussed are (1) damage to the covers of the downstream IDs by radiation from the upstream IDs and (2) proper steering of the electron beam to get the best photon beam properties. After tests in several configurations, including one where an ID was run without an impedance-reducing cover, the damage issue was solved by installing a distributed absorber in the most downstream ID. The steering issues were mostly resolved by the introduction of appropriate corrector magnets and feedback. The paper is written from the viewpoint of an interested beamline scientist impressed with the cooperation of different groups to make a source for new science possible. [ABSTRACT FROM AUTHOR]

Low-mass population III (PopIII) stars could survive up until the present. They would be found in the halo of Our Galaxy, if they exist. Non-detection of low-mass PopIII stars in our Galaxy suggests that PopIII stars have a top-heavy IMF. On the other hand, some claims that the lack of such stars is as a result of metal enrichment of their surface by accretion of heavy elements from interstellar medium (ISM). We investigate effects of the stellar wind on the metal accretion onto low-mass PopIII stars because accretion of the local ISM onto the Sun is prevented by the solar wind even for neutrals. We find that low-mass PopIII stars traveling across the Galaxy forms the stellar magnetosphere in most of their life. Once the magnetosphere is formed, most of neutral interstellar particles are photoionized before reaching to the stellar surface and are blown away by the wind. This demonstrates that low-mass PopIII stars remain pristine and will be found as metal free stars and that further searches for them are valuable to constrain the IMF of PopIII stars. [ABSTRACT FROM AUTHOR]

Low-mass population III (PopIII) stars could survive up until the present. They would be found in the halo of Our Galaxy, if they exist. Non-detection of low-mass PopIII stars in our Galaxy suggests that PopIII stars have a top-heavy IMF, On the other hand, some claims that the lack of such stars is as a result of metal enrichment of their surface by accretion of heavy elements from interstellar medium (ISM). We investigate effects of the stellar wind on the metal accretion onto low-mass PopIII stars because accretion of the local ISM onto the Sun is prevented by the solar wind even for neutrals. We find that low-mass PopIII stars traveling across the Galaxy forms the stellar magnetosphere in most of their life. Once the magnetosphere is formed, most of neutral interstellar particles are photoionized before reaching to the stellar surface and are blown away by the wind. This demonstrates that low-mass PopIII stars remain pristine and will be found as metal free stars and that further searches for them are valuable to constrain the IMF of PopIII stars. [ABSTRACT FROM AUTHOR]

CH3NH3PbI3 added with GeI2 or ZnI2 perovskite photovoltaic devices were fabricated characterized. The surface coverages of the perovskite layers were improved by the addition of GeI2 or ZnI2. Formation of PbI2 observed for the pristine CH3NH3PbI3 was suppressed by the GeI2 or ZnI2 addition, which resulted in the improvement of the conversion efficiencies of the perovskite photovoltaic devices. [ABSTRACT FROM AUTHOR]

CH3NH3PbI3-xClx photovoltaic devices were fabricated, and the effects of hot airflow during spin-coating were investigated. Cubic perovskite crystals that is a high temperature phase were obtained by the hot airflow method. The conversion efficiencies of the devices prepared by the hot airflow were remained even after 56 days. [ABSTRACT FROM AUTHOR]

Fiber-reinforced thermoplastics (FRTPs) have been used for wide variety of applications due to their high mechanical performance and light weight. The properties of molded FRTPs depend on the fiber length and they increase until the finer length in them reaches a certain length. However, it is difficult to keep the length long in the compounding and molding process avoiding the fiber breakage. Based on the above background, the objective of this study was to predict the degree of fiber breakage and control the fiber length in compounding process using the twin screw extruders. Two different laboratory sizes of extruders were used to observe the carbon fiber length in polypropylene matrix. The screw configurations composed of full-flight screws only and the combinations of right, left, and neutral kneading blocks. In the former case, the fiber breakage was caused by the full-flight screw only, suggesting the screw root depth had a significant effect. In the latter, it was cleared that fiber breakage rate was correlated with the mean shear stress obtained by the 3D numerical simulations. [ABSTRACT FROM AUTHOR]

A novel RF ion source equipped with multi-cusp magnets was developed for higher availability of ion beam milling systems without filaments and for active ion species like oxygen. We call it RF bucket ion source. The multi cusp magnets are set inside the RF coil between slits on the Faraday shield around the discharge chamber to confine plasma. This configuration reduced plasma loss and sputtering of the side wall. It enabled high throughput process with long available operation time between maintenances and caused no disturbance in inductively coupling of RF power to plasma. The RF bucket sources produced large area ion beams with beam extraction area of 300mm diameter. Ar ion beam current density is more than 1mA/cm2 with beam current of 0.9A. The RF bucket ion sorces have been installed in the Ar+ ion beam milling systems, which are continuously operating for 24 hours per a day without stop in commercial industrial factories for fabrication processes of micro-structures. The SiO2 milling uniformity of ±0.47 % at the average milling rate of 48.8 nm/minutes was obtained with optimized conditions and grid structures. The ion source could also produce active ion species such as O, F and others, which are expected to contribute to other novel application processes. [ABSTRACT FROM AUTHOR]

Brilliant pulsed x-ray synchrotron radiation (SR) is useful for pump-probe experiment such as time-resolved x-ray diffraction, x-ray absorption fine structure, and x-ray spectroscopy. For laser pump-SR x-ray probe experiments, short pulsed lasers are generally synchronized to the SR master oscillator controlling the voltage for acceleration of electron bunches in an accelerator, and the interval between the laser and the SR pulses is changed around the time scale of target phenomenon. Ideal delay control produces any time delay as keeping the time-precision and pointing-stability of optical pulses at a sample position. We constructed the time delay control module using a continuous phase shifter of radio frequency signal and a frequency divider, which can produce the delayed trigger pulses to the laser without degradation of the time precision and the pointing stability. A picoseconds time-resolved x-ray diffraction experiment was demonstrated at SPring-8 storage ring for fast lattice response by femtosecond pulsed laser irradiation, and suggested the possibility of accurate sound velocity measurement. A delay control unit operating with subpicosecond precision has also been designed for femtosecond pump-probe experiments using a free electron laser at SPring-8 campus. [ABSTRACT FROM AUTHOR]

Focused-beam flat-sample method (FFM) is a new trial for synchrotron powder diffraction method, which is a combination of beam focusing optics, flat shape powder sample and area detectors. The method has advantages for Xray diffraction experiments applying anomalous scattering effect (anomalous diffraction), because of 1. Absorption correction without approximation, 2. High intensity X-rays of focused incident beams and high signal noise ratio of diffracted X-rays 3. Rapid data collection with area detectors. We applied the FFM to anomalous diffraction experiments and collected synchrotron X-ray powder diffraction data of CoFe2O4 (inverse spinel structure) using X-rays near Fe K absorption edge, which can distinguish Co and Fe by anomalous scattering effect. We conducted Rietveld analyses with the obtained powder diffraction data and successfully determined the distribution of Co and Fe ions in CoFe2O4 crystal structure. [ABSTRACT FROM AUTHOR]

Fiber optics for controlling the x-ray beam trajectory has been examined at the synchrotron facility of SPring-8. Up to now, we have achieved beam deflection by several tens of milli-radian and axis shift of around 75 mm with a 1.5 m-long flexible hollow glass capillary. The achievable beam deflecting angle, axis shift, and timing delay are, in principle, proportional to the length, the square of length and the cube of length, respectively. Thus, for further applications, requiring larger beam shift and pulse delay, longer fibers are indispensable. In order to achieve longdistance transport using the fiber, we thus examined the connection transferring x-rays between fibers in an experimental hutch. The acceptance angle at the input end and the throughput efficiency of the second fiber is consistent with the consideration of the output beam divergence of the first fiber. The enhancement of the transfer efficiency is also discussed for the cases of a closer joint and the use of a refractive lens as a coupler. [ABSTRACT FROM AUTHOR]

Low-cost, high-performance non-evaporable getter (NEG) pumps were constructed using commercial NEG pills comprising 70 wt% Zr, 24.6 wt% V, and 5.4 wt% Fe, a conflat flange with an outer diameter of 70, 152, or 203 mm (DN 40 CF, DN 100 CF, and DN 160 CF, respectively), and a tantalum heater. After activation at 400 °C for 30 min, the pumping speeds of a DN 40 CF NEG pump measured with the orifice method were 47-40, 8-6, 24-17, and 19-15 L/s for H2, N2, CO, and CO2 gasses, respectively. NEG pumps using DN 100 CF and DN 160 CF were also developed, and their pumping speeds are estimated. These NEG pumps are favorable alternatives to sputtering ion pumps in VSX beamlines because they do not produce hydrocarbons except during the activation period. The NEG pumps can also be used for accelerators, front ends, end stations, and differential pumping systems. [ABSTRACT FROM AUTHOR]

Difference in NEA activation processes on GaAs(100) has been investigated with high resolution photoemission spectroscopy. It was found that the NEA surface produced by different activation processes cart be classified into three phases having characteristic chemical reactions of Cs and Oxygen with GaAs. A schematic phase diagram is presented to understand NEA activation processes. [ABSTRACT FROM AUTHOR]

We propose a numerical method to approximate a given continuous distribution by a discrete distribution with prescribed moments. The approximation is achieved by minimizing the Kullback-Leibler information of the unknown discrete distribution relative to the known continuous distribution (evaluated at given discrete points) subject to some moment constraints. We study the theoretical error bound and the convergence property of the method. The order of the theoretical error bound of the expectation of any bounded measurable function with respect to the approximating discrete distribution is never worse than the integration formula we start with, and therefore the approximating discrete distribution weakly converges to the given continuous distribution. Moreover, we present some numerical examples that show the advantage of our method. [ABSTRACT FROM AUTHOR]

This article compares isotropic and kinematic hardening rules for square hollow section (SHS) numerical modelling under cyclic bending loading. Hot-rolled and cold-formed SHSs are used. For the cold-formed SHS, the kinematic hardening rule produces hysteresis, which is consistent with the experimental results. However, for the hot-rolled SHS, which has a lower yield ratio, both isotropic and kinematic hardening rules are required. The isotropic hardening parameters for the hot-rolled SHS were obtained using several published equations, and the kinematic hardening parameters were obtained by fitting to existing data. A combined hardening rule was applied to the hot-rolled SHS model, and the obtained hysteresis was consistent with experimental results. The results provide insight into the behavior of hot-rolled and cold-formed SHSs. They can be used to select the hardening rules for cyclic behavior analysis. [ABSTRACT FROM AUTHOR]

It is difficult to detect a closed crack by conventional ultrasonic testing. However, nonlinear ultrasonics may be useful for detection of a closed crack in structures. This study experimentally examined propagation of ultrasonic waves through the interface between contacting solids. We simulated a closed crack by compressing two aluminum blocks. The input frequency was changed in the range of 1.0-2.0MHz and two different types of surface roughness of specimens were used. As a result, generation of low-frequency components at about 600 kHz was found regardless of the input frequency. Such a feature of low-frequency components is different from that of subharmonics. Additionally, this phenomenon was not confirmed in specimens with smoother surface. Therefore, surface roughness can be one of important factors of generating low-frequency components. The results suggest that these low-frequency components can be useful for detecting a closed crack. [ABSTRACT FROM AUTHOR]

The resistance of some bacteria towards current antibiotics calls for a new development of antibiotics. Robusta coffee (Coffea canephora) contains active compounds with antibacterial effects such as chlorogenic acid, caffeine, caffeic acid, and quinic acid. Intracellular ions such as potassium and magnesium have important roles in bacterial life. This study aims to investigate the potential antibacterial effect of Coffea canephora and its possibility in damaging bacterial cell walls and membranes through efflux of potassium and magnesium ions. This experimental study used three types of bacteria Methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae, and Pseudomonas aeruginosa, each divided into a control group and an experimental group with different concentrations. Efflux of potassium and magnesium ions in bacteria was measured using an atomic absorption spectrophotometer (AAS), while changes in bacterial cell wall morphology were observed using a scanning electron microscope (SEM). Coffea canephora is found to significantly increase the magnesium efflux of all bacteria compared to the control group (p < 0.05), while the potassium efflux only significantly increases in MRSA and Klebsiella pneumoniae. In observations using SEM, changes in the morphology of bacterial cell walls are found in the experimental group, indicating a damaging effect caused by Coffea canephora. [ABSTRACT FROM AUTHOR]

The recovery of J-PARC from the big earthquake appeared on 2011 March 11 is reported. Recovery itself was mostly completed by the end of 2011 and we could start the accelerator operation from December 9. Slow extraction from main 50 GeV-accelerator started in February 2012 and the fast extraction for T2K experiment followed it. J-PARC activities on particle and nuclear physics after the earthquake up to now are briefly summarized, and our new 5-year future plan is described, too. [ABSTRACT FROM AUTHOR]

With computer simulations of the hard sphere model, we examine in detail the microscopic pathway connecting the metastable melt to the emergence of crystalline clusters. In particular we will show that the nucleation of the solid phase does not follow a two-step mechanism, where crystals form inside dense precursor regions. On the contrary, we will show that nucleation is driven by fluctuations of orientational order, and not by the density fluctuations. By considering the development of the pair-excess entropy inside crystalline nuclei, we confirm that orientational order precedes positional order. These results are at odd with the idea of a two-step nucleation mechanism for fluids without a metastable liquid-liquid phase separation. Our study suggests the pivotal role of bond orientational ordering in triggering crystal nucleation. [ABSTRACT FROM AUTHOR]

Contrary to the conventional wisdom that there exists only one unique liquid state for any material, there are growing experimental and numerical evidence for the existence of more than two liquid states in a single component substance. The transition between them is called liquid-liquid transition (LLT). LLT has attracted considerable attention because of its counterintuitive nature and its importance in the fundamental understanding of the liquid state. However, the physical nature of the transition has remained elusive. Particularly for water, the possible existence of LLT has special implications not only on its fundamental understanding, but also on a link of various thermodynamic and transport anomalies with critical anomaly associated with LLT. In this paper, we show experimental indications for a LLT in aqueous solutions of glycerol. We demonstrated that LLT proceeds through two types of kinetics characteristic of the first order transition: nucleation-growth (NG) and spinodal-decomposition (SD) type transformation. We also reveal that local tetrahedral ordering of water molecules play a key role, which is suggestive of the presence of LLT in pure water. [ABSTRACT FROM AUTHOR]

Water is known to exhibit a number of anomalous behaviors and to be an exceptionally poor glass-former. However, both features are strongly affected by applying pressure or adding salt. This means that these two parameters have strong influence on physical factors controlling the unusual features of water. By using a water/salt mixture as a model system, we experimentally demonstrate that the glass-forming ability and the fragility of a water/salt mixture are closely related to its equilibrium phase diagram. The key to this link may be frustration between local ordering and global ordering toward the crystal. Relying on the same role of salt as pressure in water anomalies as a breaker of local tetrahedral order, we infer the behavior of water under pressure from that of a water/salt mixture. This scenario not only explains unusual behavior of water-type liquids such as water, Si and Ge under pressure, but also may provide a general explanation on the link between the equilibrium phase diagram, the glass-forming ability, and the fragility of various materials for a wide class of materials. [ABSTRACT FROM AUTHOR]

Here we study the late-stage coarsening dynamics of droplet phase separation in the unstable region of an offsymmetric binary fluid mixtures by using numerical simulations. We show that even when there are no thermal noises, the coarsening process of droplet spinodal decomposition is significantly faster in a fluid mixture than in a solid mixture. We reveal that this is due to spontaneous motion of droplets, which is induced by a non-trivial dynamic coupling between concentration field and hydrodynamic flow. Possible implications of this mechanism are also discussed. [ABSTRACT FROM AUTHOR]

The origin of slow dynamics near glass transition and the mechanism of crystal nucleation are two unsolved fundamental problems associated with the metastable supercooled state of a liquid. So far these phenomena have been considered rather independently, however, we have revealed an intimate link between them. Recently we found that crystallike bond orientational order develops in the supercooled state of (nearly) single-component systems such as spin liquids and weakly polydisperse colloidal liquids. In these liquids, low free-energy configurations in a supercooled liquid have a link to the rotational symmetry which is going to be broken upon crystallization. We argue that this is a direct consequence of that the same free energy governs both glass transition and crystallization at least in this type of liquids. We found that it is such structural ordering at least in this type of liquids that causes glassy slow dynamics and dynamic heterogeneity. Furthermore, we revealed that such structural order also plays a crucial role in crystal nucleation: Crystallization is a process of the enhancement of spatial coherence of crystal-like bond orientational order and 'not' driven by translational order at least in the nucleation stage. These results clearly indicate that the theoretical description at the two-body level is not enough to describe these phenomena and it is crucial to take into account many body correlations, particularly, bond orientational correlations. We argue that there is an intrinsic link between glass transition and crystallization if crystallization does not accompany other processes such as phase separation. If crystallization involves phase separation, on the other hand, such a direct link may be lost. We speculate that even in such a case glassy structural order may still be associated with low free-energy local configurations. [ABSTRACT FROM AUTHOR]

Measurement of negative hydrogen ions (H-) is one of the important diagnostics for development of negative ion sources. Cavity-Ring-Down (CRD) measurement system was successfully implemented for the H- density measurements in the Field-Effect-Transistor based Radio Frequency ion source. Reliability of the CRD system was experimentally confirmed, and basic characteristics of the H- ions and the ion source were studied. The measured H- density varied from 1015 to 1016 m-3 depending on the source parameters, such as input RF power, axial magnetic field in the driver region, and source pressure. The H- density increased linearly with increase of the RF power and the axial magnetic field increased, due to improvement of power transmission and plasma production efficiency. Source gas pressure dependence of the Hdensity showed an increase of H- density with the decrease of pressure. Higher electron temperature and lower neutral gas resulted in increased production of vibrationally excited molecules and decreased destructions of H- ions, which was feasible for in high H- density at low source pressure. [ABSTRACT FROM AUTHOR]

A decade after their first discovery, the origin of giant supermassive black holes (SMBHs), with masses in excess of 109 M⊙, at redshifts as early as z > 6, remains a puzzle. One possibility is that stellar-mass 'seed' BHs, left behind by the first stars, accrete gas at close to the Eddington limit during a large fraction (>= 50%) of the time. While maintaining such a high accretion rate may itself be difficult, here we focus on another, less commonly discussed problem in this scenario: unless BH seed formation and growth are preferentially suppressed in less massive protogalaxies, the mass density in M∼106M⊙ SMBHs at z ∼ 6 already exceeds the locally observed SMBH mass density by several orders of magnitude. We show that the X-rays from the earliest accreting BHs themselves can cause a self-regulation, by partially ionizing and heating the intergalactic medium (IGM). This 'global warming' suppresses the formation and growth of subsequent generations of BHs in low-mass halos, and can produce excellent agreement with recent estimates of the z = 6 SMBH mass function, without impeding the growth of the largest (M>=109M⊙) holes, which reside in the most massive galaxies that formed first. The proposed gravitational-wave observatory eLISA could detect several tens of major mergers between SMBHs at z > 6. [ABSTRACT FROM AUTHOR]

This paper deals with water-surface breakup, spray formation and material damage caused by ultrasonic waves with the frequency of 1 MHz which were focused at the free surface in the cases where a 3 mm thick acrylic plate was present or not. From the observations by means of high-speed photography with the maximum rate of 50,000 frames/sec, together by taking plenty of snapshots, it was found that when nothing was present in a fluid a variety of surface responses took place depending on the acoustic properties of ultrasound, especially acoustic intensity. When an acrylic plate existed in a fluid, wave interaction played an important role to cumulative damage in an acrylic plate. [ABSTRACT FROM AUTHOR]

Under suitable conditions quantum eigenfunctions for mixed systems localize neither on the regular nor on chaotic components in phase space. Such exotic quantum states are called amphibious states, and the flooding of wave functions from regular to chaotic regions, or in the opposite way, are predicted to occur when the eigenstates become amphibious. The emergence of such new states has so far been verified in rather artificial model systems. Here we explore how generically the flooding of wave functions takes place and whether it is an observable phenomenon even in laboratory experiments such as atomic matter-wave systems. Since the flooding occurs as a result of the strong correlation between different types of quantum localization, dynamical tunneling and dynamical localization, there are several competing factors, some of them accelerate but other do not. We study a quasi-periodic kicked rotor with generic phase space to search optimal situations to realize the flooding phenomenon and discuss the compatibility of competing factors between different types of quantum localization. [ABSTRACT FROM AUTHOR]

Spectropolarimetry is one of the most powerful methods to study the multi-dimensional geometry of extragalactic supernovae (SNe). We have performed spectropolarimetric observations of Type Ib/c SNe with the Subaru telescope. The data clearly show the "loop" in the Stokes Q - U plane. By performing 3D radiative transfer simulations, we show that the loop is clear evidence for 3D, non-axisymmetric geometry of SNe. We also summarize the properties of the line polarization of Type Ib/c SNe. We find that a stronger line tends to show a higher line polarization. This effect must be corrected to compare the polarization of different lines or different objects. [ABSTRACT FROM AUTHOR]

Recovery process of J-PARC from the disastrous influences of the Tohoku Regional Pacific Coast Earthquake is briefly summarized. Recovery itself is favorable for J-PARC and will be completed by the end of this year. We aim to perform 2-cycle (2 months) operation by the end of March (end of this Japanese Fiscal Year). Recent Activities of J-PARC on Particle and Nuclear Physics are also described. [ABSTRACT FROM AUTHOR]

Supernova remnants (SNRs) are prime candidates for acceleration sites of cosmic rays. In the last ~15 years, X-ray and TeV gamma-ray observations of SNRs indeed provided evidence that expanding SNR shells are able to accelerate charged particles up to TeV energies. Improved sensitivities of X-ray and TeV gamma-ray instruments enabled not only the detection of nonthermal radiation but also detailed spectral and morphological studies of SNRs. A new window for those studies has recently been opened by the Large Area Telescope (LAT) aboard the Fermi Gamma-ray Space Telescope, which is sensitive to gamma rays in the GeV band. Fermi LAT data put new constraints on emission mechanisms of young SNRs such as RX J1713.7-3946, and RX J0852.0-4622, which are known also as emitters of non-thermal X-rays and TeV gamma rays. Another important finding by the Fermi LAT is bright GeV emission from middle-aged SNRs interacting with molecular clouds, such as W44, W51C, and IC 443. We summarize recent X-ray and gamma-ray observations of non-thermal emission from SNRs. We also discuss possible scenarios to explain multi-wavelength spectra of SNRs. [ABSTRACT FROM AUTHOR]

In this work we evaluate different dark current models applied in QWIPs. In order to avoid empirical parameters we calculate the sequential tunneling probability of the lowest energy state to reproduce the dark current properties. Using the same arguments, the photocurrent is replaced by the tunneling probability modulated by the optical matrix element. Considering the different tunneling models presented in literature we apply a genetic algorithm to evaluate the models role on the election of the optimized infrared sensor. [ABSTRACT FROM AUTHOR]

Toroidal plasma current is started and ramped up by injecting microwave power in the electron cyclotron range of frequency without induction in the LATE device. Radial scanning with hard X-ray pulse height analysis reveals the production of high energy electrons with average energy ∼100 keV in the radial region from R = 28 cm to 40.5 cm, which are heated by electron Bernstein wave. The radial profile of photon counts in the energy range from 25 to 200 keV is very similar to that of perpendicular pressure obtained by magnetic measurement and equilibrium analysis, suggesting that a significant portion of trapped electrons exists outside the last closed flux surface. The plasma current inside the LCFS is carried mainly by passing electrons, while some portion of the outside current may be generated as a result of the toroidal precession of trapped electrons. [ABSTRACT FROM AUTHOR]

We report measurements of neutrino induced pion production processes on carbon target with an average energy of ∼0.8 GeV by SciBooNE experiment at Fermilab. These measurements are important inputs for current and future accelerator-based neutrino oscillation experiments in the interpretation of neutrino oscillation signals. [ABSTRACT FROM AUTHOR]

We discuss the QCD sum rule calculation of the heavy-quark effective theory parameters λE and λH, which represent quark-gluon three-body components in the B-meson wave function. We update the sum rules for λE,H calculating the new higher-order contributions to the operator product expansion for the corresponding correlator, i.e., the order αs radiative corrections to the Wilson coefficients associated with the dimension-5 quark-gluon mixed condensate, and the power corrections due to the dimension-6 vacuum condensates. We find that the new radiative corrections significantly improve stability of the corresponding Borel sum rules, modifying the values of λE,H. [ABSTRACT FROM AUTHOR]

The next generation of compact tandem-type DD or DT neutron generators requires a robust electron stripper with high charge exchange efficiency. In this study, stripping foils of various types were tested, and the H- to H+ conversion efficiency, endurance to the heat load, and durability were investigated in terms of suitability in the tandem-type neutron generator. In the experiments, a H- beam was accelerated to about 180 keV, passes through a stripping foil, and produces a mixed beam of H-, H0, and H+. These ions were separated by an electric field, and detected by a movable Faraday cup to determine the conversion efficiency. The experimental results using thin foils of diamond-like carbon, gold, and carbon nano-tubes revealed issues on the robustness. As a new concept, a H- beam was injected onto a metal surface with an oblique angle, and reflected H+ ions are detected. It was found that the conversion efficiency, H+ fraction in the reflected particles, depends on the surface condition, with the maximum value of about 90%. [ABSTRACT FROM AUTHOR]

In this paper we establish algebraic independence of the values of a certain infinite product as well as its all successive derivatives at algebraic points other than its zeroes, using the fact that the logarithmic derivative of an infinite product gives a partial fraction expansion. Such an infinite product is generated by a linear recurrence. The method used for proving the algebraic independence is based on the theory of Mahler functions of several variables. [ABSTRACT FROM AUTHOR]

It has been considered that a maximal entangled state is needed for complete quantum teleportation. However, Kossakowski and Ohya proposed a scheme of complete teleportation for nonmaximal entangled state [1]. Basing on their scheme, we proposed a teleportation model of 2-level state with a non-maximal entangled state [2]. In the present study, we construct its expanded model, in which Alice can teleport m-level state even if non-maximal entangled state is used. [ABSTRACT FROM AUTHOR]

I review VLF observations of magnetar flares and their numerical simulations. First, I present a brief observational summary of magnetars from the viewpoint of high-energy astrophysics. What I would like to stress here is that peak spectra of giant flares from magnetars are poorly understood due to saturation problems of X-ray and gamma-ray instruments in space, because the peak flux is very huge. VLF amplitude and phase observations enables us to estimate the peak spectra. Second, I present Monte Carlo simulations which are needed to estimate the altitude profile of electron number density when gamma-rays are directed onto the ionosphere. After that, Finite-Difference Time-Domain (FDTD) simulations are shown which simulate VLF wave propagation. Finally, summary and future perspectives are presented. [ABSTRACT FROM AUTHOR]

This paper describes the comparative study of near-field nano-processing of glass and silicon by use of metallic nano-particle and dielectric nano-particle excited by an 820 nm near-infrared femtosecond laser pulse. Near electromagnetic field around metallic nano-particle and dielectric particle shows quite unique properties on the substrate to be near-field processed. It is found that the existing thought that the use of the metallic particle is better than the dielectric particle in a much smaller particle size region than excitation wavelength is NOT always correct. As for near-field enhancement on low refractive index glass substrates by the dielectric particle with appropriate refractive index, an enhancement factor at the TE1 (magnetic dipole mode) resonance mode is found to be higher than that induced by gold particle even at the TM1 (electric dipole mode) resonance mode of gold particle. Conversely, on a high refractive index substrate like silicon, the near-field enhancement factor becomes larger by use of the gold particle at the same particle size. This significant change of the enhanced field intensity stems from the different nature of power flow based on the image charge induced in the substrate. These results indicate that the best combination of the particle and substrate for efficient localized near-field nano-processing is important for selecting either the metallic or dielectric particle. The obtained result gives a useful means for the particle selection and understanding of near-field interaction physics with substrate for efficient nano-processing of the substrate surface. Finally, these theoretical results have been verified by experiment. [ABSTRACT FROM AUTHOR]

The infrared free electron laser (FEL) and the parametric X-ray radiation (PXR) developed on the basis of the 125 MeV electron linac at Nihon University have been applied to studies in a variety of scientific fields. Primary users so far are the faculty members in the university, approximately 2000 hr/year of the machine time having been dedicated to the experiments since 2004. Currently the wavelength range of the FEL served for users’ experiments covers 1500 to 6000 nm at the optical power level of 10 to 30 mJ/macropulse. Combination of the fundamental infrared FEL with BBO non-linear optical crystals yielded higher harmonics with good conversion efficiencies, which has extended the available wavelength range as short as approximately 400 nm. The PXR generator has employed a double-crystal system so that the monochromatic X-ray beam is available at a fixed output port independently of the X-ray center energy. By using a Si(111) crystal as the PXR target the energy variable monochromatic X-ray beam from 5 to 20 keV has been successfully applied to users’ experiments. The latest work on the PXR generation using a Si(220) target crystal has demonstrated availability of the X-ray beam with energies up to approximately 34 keV. [ABSTRACT FROM AUTHOR]