Evaluating mixed-mode stress intensity factors from full-field displacement fields obtained by optical methods

A method for evaluating mode I, mode II and mixed-mode stress intensity factors from in-plane displacement fields using the method of nonlinear least-squares is proposed in this paper. Along with stress intensity factors, crack tip location and rigid body displacement components are determined simultaneously from both displacement components obtained using full-field optical methods or numerical methods. The effectiveness is validated by applying the proposed method to mixed-mode displacement fields obtained through digital image correlation, displacement fields obtained by analysis using elasto-plastic finite element method, and displacement fields around a fatigue crack obtained by electronic speckle pattern interferometry. Results show that the proposed method can extract stress intensity factors from the displacement fields both accurately and easily. Furthermore, they can be determined even if the material at a crack tip exhibits small-scale yielding. It is expected that the proposed method is applicable to various fracture problems during experimental and numerical evaluation of structural components.     

Extracting fuzzy control rules from experimental human operatordata

This paper proposes an approach where the interpretation of manual control strategies is carried out by modeling the human operator as a fuzzy logic controller. The linguistic rules thus obtained can provide a better insight into the operator's actions, allowing mistakes to be more easily pinpointed and corrected. Instead of extracting the control rules directly from raw experimental data, an intermediary ARMA model for the operator is employed to improve the data consistency. For illustration, this method is applied to the problem of supervising an apprentice operator, with basis on rules extracted from the actions of an experienced manual operator.     

Bit error rate degradation due to a dip in the frequency responseof an equalizing amplifier

This paper describes an analysis of bit error rate (BER) degradation due to a dip in the frequency response of an equalizing amplifier. An equivalent circuit simulation clarifies the BER degradation factors: (1) the output amplitude decrease of a specific binary sequence that has a repetition frequency equal to the dip frequency and (2) the oscillation in output voltage after rise and fall of signal level. A simple model shows that the center frequency and bandwidth of the dip as well as the depth of the dip strongly affect BER. A circuit simulation and experiment show that a dip at around one tenth the data rate causes the worst BER. The dip tolerance of a dc-suppressed transmission code is also discussed     

Analyses of mild hydrogenation products of coals treated with zinc and butyl iodide

Butylation using zinc and butyl iodide under mild conditions (130 °C and atmospheric pressure) is an effective method to convert solid coals to soluble products in poor solvents such as hexane and benzene. Because of mild conditions and high solubility, the butylation of coals is found to be applicable for estimating coal structures. Until now, two typical coals, Taiheiyo and Yubari coals, were converted to hexane soluble products significantly. However they were too heavy to obtain much information on the structure of the original coals. In order to analyze the structural features of the coals butylated with zinc and butyl iodide, the polar mixture (PM) fractions separated from hexane soluble products (HS) from butylated Yubari and Taiheiyo coals were hydrogenated using Adkins catalyst. The HS products of hydrogenated PM fractions were fractionated by gel permeation chromatography (GPC), and the GPC fractions were further analyzed. After hydrogenation, structural parameters of HS products separated from PM fractions did not change so much, but molecular weight decreased. The GPC fractions (Fr.1–Fr.7) from both coals had similar high σal (degree of aliphatic chain substitution) as well as low fa (aromaticity) to the original PM fractions. These results indicated that the GPC fractions were highly butylated. Many structural parameters of GPC fractions except for Fr.7 were similar with each other. For Taiheiyo coal, the ring sizes of GPC fractions were 1–2, and similar to those from pyridine soluble products. For Yubari coal they were 2–3, and smaller than those from pyridine soluble product, 4 due to reductive butylation. The ring sizes of the Fr.7 from both coals were as small as one. Because the solvent soluble products were subject to reductive butylation, the naphthenic rings of the fractions seemed to be ruptured by hydrogenation. These findings suggest that high hexane extractability of the coals butylated with zinc and butyl iodide was caused by reductive butylation.     

Evaluating the Effect of Lenvatinib on Sorafenib-Resistant Hepatocellular Carcinoma Cells

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related deaths worldwide. Sorafenib has been used as a first-line systemic treatment for over a decade. However, resistance to sorafenib limits patient response and presents a major hurdle during HCC treatment. Lenvatinib has been approved as a first-line systemic treatment for advanced HCC and is the first agent to achieve non-inferiority against sorafenib. Therefore, in the present study, we evaluated the inhibition efficacy of lenvatinib in sorafenib-resistant HCC cells. Only a few studies have been conducted on this topic. Two human HCC cell lines, Huh-7 and Hep-3B, were used to establish sorafenib resistance, and in vitro and in vivo studies were employed. Lenvatinib suppressed sorafenib-resistant HCC cell proliferation mainly by inducing G1 cell cycle arrest through ERK signaling. Hep-3B sorafenib-resistant cells showed partial cross-resistance to lenvatinib, possibly due to the contribution of poor autophagic responsiveness. Overall, the findings suggest that the underlying mechanism of lenvatinib in overcoming sorafenib resistance in HCC involves FGFR4-ERK signaling. Lenvatinib may be a suitable second-line therapy for unresectable HCC patients who have developed sorafenib resistance and express FGFR4.     

Fully electrical 40-Gb/s TDM system prototype based on InP HEMTdigital IC technologies

This paper presents a fully electrical 40-Gb/s time-division-multiplexing (TDM) system prototype transmitter and receiver. The input and output interface of the prototype are four-channel 10-Gb/s signals. The prototype can be mounted on a 300-mm-height rack and offers stable 40-Gb/s operation with a single power supply voltage. InP high-electron mobility transistor (HEMT) digital IC's perform 40-Gb/s multiplexing/demultiplexing and regeneration. In the receiver prototype, unitraveling-carrier photodiode (UTC-PD) generates 1 V_pp output and directly drives the InP HEMT decision circuit (DEC) without any need for an electronic amplifier. A clock recovery circuit recovers a 40-GHz clock with jitter of 220 fs_pp from a 40-Gb/s nonreturn-to-zero (NRZ) optical input. The tolerable dispersion range of the prototype within a 1-dB penalty from the receiver sensitivity at zero-dispersion is as wide as 95 ps/nm, and the clock phase margin is wider than 70° over almost all the tolerable dispersion range. A 100-km-long transmission experiment was performed using the prototype. A high receiver sensitivity [-25.1 dBm for NRZ (2⁷-1) pseudorandom binary sequence (PRBS)] was obtained after the transmission. The 40-Gb/s regeneration of the InP DEC suppressed the deviation in sensitivity among output channels to only 0.3 dB. In addition, four-channel 40-Gb/s wavelength-division-multiplexing (WDM) transmission was successfully performed     

Energy saving system with high effluent quality for municipal sewage treatment by UASB-DHS

An up-flow anaerobic sludge blanket (UASB) - down-flow hanging sponge (DHS) was applied to Japanese municipal sewage treatment, and its treatability, energy consumption, and sludge production were evaluated. The designed sewage load was 50 m(3)/d. The sewage typically had a chemical oxygen demand (COD) of 402 mg/L, a suspended solids (SS) content of 167 mg/L, and a temperature of 17-29 °C. The UASB and DHS exhibited theoretical hydraulic retention times of 9.7 and 2.5 h, respectively. The entire system was operated without temperature control. Operation was started with mesophilic anaerobic digested sludge for the UASB and various sponge media for the DHS. Continuous operational data suggest that although the cellulose decomposition and methanogenic process in the UASB are temperature sensitive, stable operation can be obtained by maintaining a satisfactory sludge volume index and sludge concentration. For the DHS, the cube-type medium G3-2 offers superior filling rates, biological preservation and operational execution. The SS derived from the DHS contaminated the effluent but could be removed by optional sand filtration. A comparison with conventional activated sludge (CAS) treatment confirmed that this system is adequate for municipal sewage treatment, with an estimated energy requirement and excess sludge production approximately 75 and 85% less than those of CAS, respectively.     

Route and Regulation of Zinc,Cadmium, and Iron Transport in Rice Plants (Oryza sativa L.) during Vegetative Growth and Grain Filling: Metal Transporters,Metal Speciation,Grain Cd Reduction and Zn and Fe Biofortification

Zinc (Zn) and iron (Fe) are essential but are sometimes deficient in humans, while cadmium (Cd) is toxic if it accumulates in the liver and kidneys at high levels. All three are contained in the grains of rice, a staple cereal. Zn and Fe concentrations in rice grains harvested under different levels of soil/hydroponic metals are known to change only within a small range, while Cd concentrations show greater changes. To clarify the mechanisms underlying such different metal contents, we synthesized information on the routes of metal transport and accumulation in rice plants by examining metal speciation, metal transporters, and the xylem-to-phloem transport system. At grain-filling, Zn and Cd ascending in xylem sap are transferred to the phloem by the xylem-to-phloem transport system operating at stem nodes. Grain Fe is largely derived from the leaves by remobilization. Zn and Fe concentrations in phloem-sap and grains are regulated within a small range, while Cd concentrations vary depending on xylem supply. Transgenic techniques to increase concentrations of the metal chelators (nicotianamine, 2′-deoxymugineic acid) are useful in increasing grain Zn and Fe concentrations. The elimination of OsNRAMP5 Cd-uptake transporter and the enhancement of root cell vacuolar Cd sequestration reduce uptake and root-to-shoot transport, respectively, resulting in a reduction of grain Cd accumulation.     

Design of output feedback controllers for sampled-data fuzzy systems

In this paper, the design problem of output feedback controllers for sampled-data fuzzy models is considered. We consider the case where the premise variable coincides with the state variable. We give observers and output feedback controllers for an approximation of the original system. We then apply the observers and output feedback controllers to the original system and give sufficient conditions for the asymptotic convergence and stability respectively. A design example is given to illustrate the theory.     

H 8 control for Takagi?Sugeno fuzzy systems

In this paper the design problem of output feedback H