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The CeB6(001) single crystal used as a cathode in a low‐emittance electron gun and operated at the free‐electron laser facility SACLA was investigated using cathode lens electron microscopy combined with X‐ray spectroscopy at SPring‐8 synchrotron radiation facility. Multilateral analysis using thermionic emission electron microscopy, low‐energy electron microscopy, ultraviolet and X‐ray photoemission electron microscopy and hard X‐ray photoemission spectroscopy revealed that the thermionic electrons are emitted strongly and evenly from the CeB6 surface after pre‐activation treatment (annealing at 1500°C for >1 h) and that the thermionic emission intensity as well as elemental composition vary between the central area and the edge of the old CeB6 surface. [ABSTRACT FROM AUTHOR]

A new correction algorithm for closed orbit distortion based on an adaptive feedforward control (AFC) has been developed. At SPring‐8, two helicity‐switching twin‐helical undulators (THUs) had been implemented with conventional feedforward corrections. However, the validity of these corrections turned out to be expiring due to unforeseen variation in the error magnetic fields with time. The developed AFC system has been applied to the THUs dynamically updating the feedforward table without stopping the helicity switching amid user experiments. The error sources in the two THUs are successfully resolved and corrected even while the two THUs are switching simultaneously with the same repetition period. The actual operation of the new AFC system enables us to keep the orbit variations suppressed with an accuracy at the sub‐micrometre level in a transparent way for light source users. [ABSTRACT FROM AUTHOR]

We have developed an advanced LTPS TFT technology in which top‐gate oxide TFTs are used in each pixel and CMOS LTPS TFTs are used in gate drivers and multiplexers in the peripheral circuits. Oxide TFTs have excellent Ids–Vgs characteristics with a small Vth shift under negative bias temperature illumination stress (NBTIS). [ABSTRACT FROM AUTHOR]

The SPring‐8 Ångstrom Compact free‐electron LAser (SACLA) began parallel operation of three beamlines (BL1–3) in autumn 2017 to increase the user beam time of the X‐ray free‐electron laser. The success of the multiple‐beamline operation is based on two technological achievements: (i) the fast switching operation of the SACLA main linear accelerator, which provides BL2 and BL3 with pulse‐by‐pulse electron beams, and (ii) the relocation and upgrade of the SPring‐8 Compact SASE Source for BL1, for the generation of a soft X‐ray free‐electron laser. Moreover, the photon beamlines and experimental stations were upgraded to facilitate concurrent user experiments at the three beamlines and accommodate more advanced experiments. The parallel operation of three free‐electron laser (FEL) beamlines was first conducted using the SPring‐8 Ångstrom Compact free‐electron LAser (SACLA), to offer more opportunities for advanced studies using X‐ray FELs. [ABSTRACT FROM AUTHOR]

We propose an advanced LTPS TFT‐LCD technology in which top‐gate oxide TFTs are used in each pixel, whereas LTPS TFTs are used in the drivers and multiplexer in the frame areas. With this technology, we successfully developed a 538‐ppi TFT‐LCD prototype with 15‐Hz frame‐rate driving, a 0.5‐mm width side border, and lower gate driving voltages of +8.6/−8.0 V. Even after conducting a 500‐h driving test at 70 °C, no degradation was observed. [ABSTRACT FROM AUTHOR]

ABSTRACT Radical polymerization of cyclic analogs of acrylates, ( S)- and ( R)-2-isopropyl-5-methylene-1,3-dioxolan-4-ones ( 1S and 1R), successfully afforded a functional polymer having the tacticity continuously controlled from 29% to ∼100% of meso triad ( mm) over a wide range of temperature only by changing the molar ratio of 1S/ 1R in feed. Plot of the number fractions of the triad versus diad of poly( 1) was in good agreement with the Bernoulli statistics. In the polymerization in chiral solvents having analogs structure of the monomers, the tacticity and specific rotation of the resulting polymer were specifically varied depending on the structure and concentration of the solvents. Model propagation reaction at dimeric radical calculated with density functional theory reproduced a methodical induction of the chirality to the main chain from the branched chiral monomeric unit, which supports the experimental expectations. It is remarkable that the ceiling temperature of 1 is tremendously high, for example, 193 °C in [ 1 ( ee = 72.6%)] = 0.05 mol/L, and the isospecific polymerization is maintained even at such a high temperature, which enabled the control of polymer tacticity over a wide range of temperature. The mechanism of the stereosequence in radical polymerization was discussed experimentally and theoretically. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 184-193 [ABSTRACT FROM AUTHOR]

The design and performance of a soft X-ray free-electron laser (FEL) beamline of the SPring-8 Compact free-electron LAser (SACLA) are described. The SPring-8 Compact SASE Source test accelerator, a prototype machine of SACLA, was relocated to the SACLA undulator hall for dedicated use for the soft X-ray FEL beamline. Since the accelerator is operated independently of the SACLA main linac that drives the two hard X-ray beamlines, it is possible to produce both soft and hard X-ray FEL simultaneously. The FEL pulse energy reached 110 µJ at a wavelength of 12.4 nm (i.e. photon energy of 100 eV) with an electron beam energy of 780 MeV. [ABSTRACT FROM AUTHOR]

ABSTRACT Reversible deactivation radical polymerization (RDRP) of biomass-based acrylates, ( S)- and ( R)-2-isopropyl-5-methylene-1,3-dioxolan-4-ones ( S-MiPDO and R-MiPDO), was successfully performed to produce a well-defined polymer with simultaneously controlled tacticity and molecular weight, and low dispersity ( Đ < 1.3). In particular, meso triad ( mm) of the polymer was continuously controlled as designed from 28.1% to about 100% by changing the molar ratio of S-MiPDO/ R-MiPDO in feed. In kinetic studies, the rate of RDRP was strongly influenced by the stereostructures of the propagating radical, and it was much lower in isospecific RDRP than atactic one in reversible chain transfer catalyzed polymerization (RTCP) in contrast to atom transfer radical polymerization (ATRP) where the rate would not change regardless of the tacticity. Increase of molecular weight and low Đ of the polymer were also observed in reversible addition-fragmentation chain transfer (RAFT) polymerization of MiPDO. In addition, block copolymers including stereoblock copolymers were feasibly synthesized by RTCP of styrene and methyl methacrylate using poly(MiPDO) prepolymer. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 445-456 [ABSTRACT FROM AUTHOR]

ABSTRACT Radical polymerization of lactic acid-based chiral and achiral methylene dioxolanones, a model for conformationally s-cis locked acrylate, was carried out with AIBN to demonstrate an isospecific free radical polymerization controlled by chirality and conformation of monomer. Polymerization of the dioxolanones proceeded smoothly without ring opening to give a polymer with moderate molecular weight and 100% of maximum isotacticity. ESR spectrum indicated a twisted conformation of the growing poly(methylene dioxolanone) radical in contrast to an acyclic analogous radical, suggesting a restriction of the free rotation around main chain CαCβ bond of the growing radical center. Chirality as well as the polarity and bulkiness of monomer affected the polymer tacticity, and chiral alkyl substituent would afford a high isotactic polymer, in which higher the enantiomeric excess of the monomer was, higher the isotacticity of the polymer was. While, achiral or polar substituents including dibenzyl and trichloromethyl groups would afford an atactic polymer. In addition, glass transition temperature ( Tg) of the resulting polymers was significantly high, ranging from 172.2 to 229.8 °C, and even for an isotactic polymer Tg was as high as 206.8 °C. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2007-2016 [ABSTRACT FROM AUTHOR]

In March 2012, SACLA started user operations of the first compact X-ray free-electron laser (XFEL) facility. SACLA has been routinely providing users with stable XFEL light over a wide photon energy range from 4 to 15 keV and an ultrafast pulse duration below 10 fs. The facility supports experimental activities in broad fields by offering high-quality X-ray optics and diagnostics, as well as reliable multiport charge-coupled-device detectors, with flexible experimental configurations. A two-stage X-ray focusing system was developed that enables the highest intensity of 1020 W cm−2. Key scientific results published in 2013 and 2014 in diverse fields are reviewed. The main experimental systems developed for these applications are summarized. A perspective on the facility upgrade is presented. [ABSTRACT FROM AUTHOR]

Thermoresponsive hydrogels based on poly(methyl 2-isobutyramidoacrylate) (PMIBA) were prepared by free-radical crosslinking polymerization of the corresponding monomer using N, N′-methylenebisacrylamide as a crosslinker. The PMIBA hydrogels showed a reversible temperature-induced volume change with a volume phase transition temperature (VPTT) at 19°C, while they contained more than 60 wt % water even in the equilibrium deswollen state. When the external temperature was raised rapidly above the VPTT, the PMIBA gels shrank smoothly with time at a faster rate than conventional poly( N-isopropylacrylamide) hydrogels of the same size. The fast and smooth deswelling response of the PMIBA gel is ascribed to its sponge-like structure with 0.1-1 µm pore sizes formed in the deswollen state. The smooth deswelling response due to the macroporous structure resulted in high durability against repeated changes in the external temperature. The PMIBA gel showed little degradation in the swelling ability when subjected to 50 times of thermal cycling across the VPTT. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2012 [ABSTRACT FROM AUTHOR]

SUMMARY Reinforced concrete (RC) structural walls usually have some eccentric large openings according to the intention of the architectural design. However, the behaviour of such structures that are shear critical under cyclic loading has not been well studied. In this study, three single-span, three-storied, 40% scale specimens of RC structural walls with various eccentric opening ratios were constructed and tested in a lateral reverse cyclic manner until severe shear damage occurred in the walls. The main purposes of these tests were to evaluate the shear behaviour and to recognize the influence of various opening ratios on cracking and shear strength of structural walls under cyclic loading. The shear strength of specimen was calculated combining the shear strength of a structural wall without openings and the reduction factor due to openings. The comparison between the experimental results and the analytical results shows that the shear strength is different depending on the loading direction due to the eccentric opening location, the span length of short span beams may affect the cracking process and the failure mode, the approximate calculation method using Ono's reduction factor could be well applied to RC structural walls with various opening ratios less than 0.46. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this work, we are interested in the study of regularity for the three-dimensional magneto-micropolar fluid equations in Orlicz-Morrey spaces. If the velocity field satisfies [ABSTRACT FROM AUTHOR]

The article offers a hybrid multi-model for peak flood forecasting using the soft computing approach. The hybrid multi-model combines artificial neural network (ANN), fuzzy logic and genetic algorithm (GA). The hybrid multi-model was used in estimating the flood level of the big flood at Chiang Mai, China in 2005 and the 2003 Koriyama flood in Japan. The results are evaluated using efficiency index (EI), root main square error (RMSE) and the peak flood error and then compared to the results of a neuro-genetic model (NGO) and ANFIS model. It is found that the hydrid-multi model can be used effectively in estimating and forecasting peak floods.

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Top-up operation allows SPring-8 to provide highly stable X-ray beams with arbitrary filling patterns. The implementation of top-up operation is described, with a focus on the simultaneous achievement of stability of stored current, beam orbit, purity of an isolated single bunch, and beam injection efficiency. Stored-current fluctuations have been routinely reduced to a level of 10−3. Stored-beam oscillation on frequent beam injection, which was originally regarded as the most serious problem, has been successfully suppressed to a sufficiently low level that it never perturbs imaging experiments. Current impurities in nominally empty buckets have been reduced to a level of 10−9 over more than one week of operation, making possible the measurement of time-resolved spectra using high-current bunches. Finally, excellent injection efficiency, higher than 80%, is routinely obtained, even for small undulator gaps, which is critical for preventing radiation damage to insertion-device magnets and to reduce leakage radiation. The process of achieving highly stabilized top-up operation at SPring-8 and its utility for user experiments are described. [ABSTRACT FROM AUTHOR]

This paper proposes a new neural network (the concepts-of-sentences associative neural network, CSANN) which performs memory and recall of sentences represented by a semantic network, as an approach toward natural language processing. The semantic network is represented in terms of the triples representation of concepts. The triples representation of concepts consists of concepts linked by relations in sentences represented by natural language. CSANN handles sentence data, which are difficult to handle since the data size is not unique, by decomposing the data into triples representations of concepts and integrating them into the semantic network format. It is verified by computer simulation that the proposed network can store sentences and recall sentences even if the input information is incomplete. Thus, the effectiveness of the proposed network in natural language processing is demonstrated. © 2003 Wiley Periodicals, Inc. Syst Comp Jpn, 34(11): 43–54, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10476 [ABSTRACT FROM AUTHOR]

Objective/Methods The origin and clinical implications of spontaneous otoacoustic emissions (SOAEs) have not been well revealed. To investigate the relationship between the ear with endolymphatic hydrops and SOAE, SOAEs were measured in 31 patients with unilateral endolymphatic hydrops and 10 volunteers with normal hearing levels that had less than 25 dB hearing level (HL) on average for five frequencies (0.25, 0.5, 1, 2, and 4 kHz). Results SOAEs were detected in 18 (58%) of the 31 ears with hydrops. In 15 hydropic ears in which the hearing levels were less than 25 dB HL on average, SOAEs were observed in 11 (73%). The results of examining the relationship between changes in hearing level after administering the glycerol test and SOAE frequency showed that four (50%) of eight hydropic ears had SOAEs that were detectable between the frequency in which hearing level improved more than 5 dB and the frequency with no hearing level change in the audiogram. In 28 contralateral ears, except for three cases of delayed endolymphatic hydrops, SOAEs were detected in 17 (61%). In 14 contralateral ears in which the hearing levels were less than 25 dB HL on average for the five frequencies noted above, SOAEs were observed in nine ears (64%). In 20 normal ears, SOAEs were detected in eight (40%). Prevalence of SOAEs in hydropic ears and contralateral ears of the patients with unilateral hydrops tended to be greater than that in normal ears; however, there was no significant statistical difference between them. Conclusion The present results suggest that it is not possible to mention the characteristics of SOAE in the hydropic ear only in terms of the prevalence of SOAEs. SOAEs may occur in a specific portion of the basilar membrane corresponding to the frequency in which hearing levels improve after the glycerol test, in some cases with endolymphatic hydrops. [ABSTRACT FROM AUTHOR]

The feasibility is examined of using the Miller phase-compensation circuit to ensure the stability of the voltage limiter circuit in high-density CMOS DRAMs. First, analytical expressions are obtained for the condition of stabilization to support the comprehensive circuit design and it is shown that both load capacity and load current affect the stability significantly. Second, by using the analytical expressions, parameters for the voltage limiter and the phase compensation circuit are calculated. By computer simulation and experiment voltage variations within the chip are evaluated when the internal circuit operates and external power supply voltage is changed. Results show that the voltage variation caused by the operation of the internal circuit is within 10 perecent, resulting in no problem in practice. The voltage variation caused by the change in the external power supply voltage is 3 percent in the case of low-frequency noise (tr, tf=1 μs) and is as large as 20 percent in the case of high-frequency noise (tr, tf=10 ns) and attention must be paid to the latter case in the circuit design. [ABSTRACT FROM AUTHOR]