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Using the recently introduced adaptive density-matrix renormalization-group method, we study the many spin-spin correlations of the spin-$1/2$ antiferromagnetic Heisenberg chain with random coupling constants, namely, the mean value of the bulk and of the end-to-end correlations, the typical value of the bulk correlations, and the distribution of the bulk correlations. Our results are in striking agreement with the predictions of the strong-disorder renormalization group method. We do not find any hint of logarithmic corrections neither in the bulk average correlations, which were recently reported by Shu et al. [Phys. Rev. B 94,174442 (2016)], nor in the end-to-end average correlations. We report computed the existence of logarithmic correction on the end-to-end correlations of the clean chain. Finally, we have determined that the distribution of the bulk correlations, when properly rescaled by an associated Lyapunov exponent, is a narrow and universal (disorder-independent) probability function., (v1) 8 pages, 8 figures; (v2) extended introduction and discussion, 9 pages, 9 figures, published version

Epidermolysis bullosa (EB) is a group of genodermatoses characterized by generalized blisters from mutations in the genes encoding the basement membrane zone (BMZ) proteins.1 The infusion of allogeneic cells such as mesenchymal stem/stromal cells (MSCs), which have intact BMZ genes, is a promising treatment.

In this paper we study the critical properties of the non-equilibrium phase transition of the Susceptible-Exposed-Infected model under the effects of long-range correlated time-varying environmental noise on the Bethe lattice. We show that temporal noise is perturbatively relevant changing the universality class from the (mean-field) dynamical percolation to the exotic infinite-noise universality class of the contact process model. Our analytical results are based on a mapping to the one-dimensional fractional Brownian motion with an absorbing wall and is confirmed by Monte Carlo simulations. Unlike the contact process, our theory also predicts that it is quite difficult to observe the associated active temporal Griffiths phase in the long-time limit. Finally, we also show an equivalence between the infinite-noise and the compact directed percolation universality classes by relating the SEI model in the presence of temporal disorder to the Domany-Kinzel cellular automaton in the limit of compact clusters., Comment: 10 pages, 4 figures

Nesta tese estudamos os efeitos da desordem espacial e temporal na transição de fase entre a sobrevivência e extinção de populações biológicas. Na primeira parte estudamos um modelo epidemiológico com quatro estados. Apesar deste modelo não conter desordem, concluímos que seu comportamento crítico é o mesmo do processo de contato com desordem (espacial) quenched. Na segunda parte estudamos o movimento Browniano fracionário refletido, onde vimos que a combinação dos efeitos do ruído com correlações de longo alcance e a parede refletora cria uma singularidade em lei de potência na densidade de probabilidade da posição do caminhante. Por fim, estudamos a equação logística com desordem temporal através do mapeamento no movimento Browniano fracionário refletido. Neste último estudo vimos como as correlações de longo alcance mudam o comportamento crítico deste sistema. We have studied the effects of spatial and temporal disorder at the phase transition between survival and extinction of biological populations. In the first part we studied a four states biological population model. Despite having no disorder, we have seen that its critical behavior is the same of the contact process with (spatial) quenched disorder. In the second part, we studied the reflected fractional Brownian motion, where the interplay between the correlated noise and the reflecting wall results in a power-law singularity in the probability density of the position of the walker. Finally, we deduced the critical properties of the logistic equation with temporal disorder by mapping it onto the reflected fractional Brownian motion. This mapping allow us to understand how long-range correlations change the critical behavior of this system.

Introduction There is a growing interest in the use of patient-reported outcomes to provide a more patient-centered view on treatment. Forgetting the artificial joint can be regarded as the goal in joint arthroplasty. The goals of the study were to describe changes in joint awareness in the artificial joint after total knee arthroplasty (TKA), and to determine which factors among pain, knee range of motion (ROM), quadriceps strength, and functional ability affect joint awareness after TKA. Hypothesis Patients undergoing TKA demonstrate changes in joint awareness and joint awareness is associated with pain, knee ROM, quadriceps strength, and functional ability. Patients and methods This prospective cohort study comprised 63 individuals undergoing TKA, evaluated at 1, 6, and 12 months postoperatively. Outcomes included joint awareness assessed using the Forgotten Joint Score (FJS), pain score, knee ROM, quadriceps strength, and functional ability. Results Fifty-eight individuals completed all postoperative assessments. All measures except for knee extension ROM improved from 1 to 6 months. However, there were no differences in any measures from 6 to 12 months. FJS was affected most greatly by pain at 1 month and by quadriceps strength at 6 and 12 months. Discussion Patients following TKA demonstrate improvements in joint awareness and function within 6 months after surgery, but reach a plateau from 6 to 12 months. Quadriceps strength could contribute to this plateau of joint awareness. Level of evidence Prospective cohort study, IV.

We analyze the influence of long-range correlated (colored) external noise on extinction phase transitions in growth and spreading processes. Uncorrelated environmental noise (i.e., temporal disorder) was recently shown to give rise to an unusual infinite-noise critical point [Europhys. Lett. 112, 30002 (2015)]. It is characterized by enormous density fluctuations that increase without limit at criticality. As a result, a typical population decays much faster than the ensemble average which is dominated by rare events. Using the logistic evolution equation as an example, we show here that positively correlated (red) environmental noise further enhances these effects. This means, the correlations accelerate the decay of a typical population but slow down the decay of the ensemble average. Moreover, the mean time to extinction of a population in the active, surviving phase grows slower than a power law with population size. To determine the complete critical behavior of the extinction transition, we establish a relation to fractional random walks, and we perform extensive Monte-Carlo simulations., Comment: 11 pages, 12 figures, Final version

A possible mechanism leading to anomalous diffusion is the presence of long-range correlations in time between the displacements of the particles. Fractional Brownian motion, a non-Markovian self-similar Gaussian process with stationary increments, is a prototypical model for this situation. Here, we extend the previous results found for unbiased reflected fractional Brownian motion [Phys. Rev. E 97, 020102(R) (2018)] to the biased case by means of Monte Carlo simulations and scaling arguments. We demonstrate that the interplay between the reflecting wall and the correlations leads to highly non-Gaussian probability densities of the particle position $x$ close to the reflecting wall. Specifically, the probability density $P(x)$ develops a power-law singularity $P \sim x^\kappa$ with $\kappa < 0$ if the correlations are positive (persistent) and $\kappa > 0$ if the correlations are negative (antipersistent). We also analyze the behavior of the large-$x$ tail of the stationary probability density reached for bias towards the wall, the average displacements of the walker, and the first-passage time, i.e., the time it takes for the walker reach position $x$ for the first time., Comment: 24 pages, 11 figures

We report on a dual-pass high current density resonant tunneling diode (RTD) for terahertz wave applications. This technique reduces the overall fabrication complexity and improves the reproducibility for creating low resistance ohmic contacts. With our dual-pass technique, we demonstrate accurate control over the final device area by measuring the RTD current–voltage characteristic during the fabrication process and guiding the emitter current through the full RTD structure with a second contact electrode on the collector side. We go on to show how we may extract important information about the RTD performance using this method.

Fractional Brownian motion, a stochastic process with long-time correlations between its increments, is a prototypical model for anomalous diffusion. We analyze fractional Brownian motion in the presence of a reflecting wall by means of Monte Carlo simulations. While the mean-square displacement of the particle shows the expected anomalous diffusion behavior $\langle x^2 \rangle \sim t^\alpha$, the interplay between the geometric confinement and the long-time memory leads to a highly non-Gaussian probability density function with a power-law singularity at the barrier. In the superdiffusive case, $\alpha> 1$, the particles accumulate at the barrier leading to a divergence of the probability density. For subdiffusion, $\alpha < 1$, in contrast, the probability density is depleted close to the barrier. We discuss implications of these findings, in particular for applications that are dominated by rare events., Comment: 6 pages, 6 figures. Final version as published

Estudamos o modelo epidemiológico denominado susceptível-exposto-infectado (SEI) na rede quadrada por meio de simulações numéricas. Nesse modelo, cada sítio da rede pode estar susceptível, exposto ou infectado. Um sítio susceptível nas vizinhanças de um infectado se torna infectado com uma certa probabilidade e exposto com probabilidade complementar. Sítios infectados ou expostos permanecem para sempre nessa condição. Mostramos que os aglomerados gerados a partir de um único infectado numa rede repleta de suscetíveis são os mesmos aglomerados presentes na percolação isotrópica. Calculamos os expoentes críticos dinâmicos com bastante precisão permitindo colocar o modelo SEI na classe de universalidade da percolação dinâmica. We have studied the epidemiologic model called susceptible-exposed-infected (SEI) on a square lattice by numerical simulations. In this model, each site of the lattice may be susceptible, exposed or infected. A susceptible site in the neighborhood of an infected site becomes infected with a given probability, or exposed with a complementary probability. Infected and exposed sites remain forever in these states. We have shown that clusters generated by a single infected site in a lattice full of susceptible are the same clusters as in the isotropic percolation. The critical dynamic exponents were calculated with large precision allowing to put the SEI model into the dynamical percolation universality class.

We report on a dual-pass high current density InGaAs/AlAs/InP resonant tunnelling diode (RTD) terahertz (THz) emitter. Our dual-pass technique reduces overall fabrication complexity, improves the reproducibility for creating low resistance ohmic contacts, and allows accurate control over the final device area. This has been made possible by measuring the RTD current-voltage (I-V) characteristic during the fabrication process and defining both contact electrodes at the start of the fabrication. We extract information about the RTD performance using this method and demonstrate fundamental room temperature emission at 0.35 THz.

The critical properties of the stochastic susceptible-exposed-infected model on a square lattice is studied by numerical simulations and by the use of scaling relations. In the presence of an infected individual, a susceptible becomes either infected or exposed. Once infected or exposed, the individual remains forever in this state. The stationary properties are shown to be the same as those of isotropic percolation so that the critical behavior puts the model into the universality class of dynamic percolation.

One of the major sources of radiated EMI is attributed to power bus resonance in a printed circuit board (PCB). A fast algorithm, combined with the segmentation method, is applied for calculating resonance characteristics of a power bus whose pattern consists of several segments of rectangles and/or right-angled triangles. Good agreement between the calculated and measured results demonstrates the usefulness and accuracy of the fast algorithm and the segmentation method.

Using spontaneously hypertensive rats (SHR) fed a standard or a Zn-deficient diet for 4 weeks, we examined whether Zn deficiency affects systemic blood pressure (BP) levels in a genetically hypertensive state through a fall in the activity of Cu/Zn-superoxide dismutase (SOD). SHR fed a Zn-deficient diet had a progressive increase in systolic BP during the dietary conditioning. Consequently, SHR fed a Zn-deficient diet exhibited significantly increased levels of systolic BP by 2 weeks after the start of dietary treatment when compared with SHR fed a standard diet. Similarly, levels of basal mean arterial pressure (MAP) observed at the end of dietary treatment were SHR fed a Zn-deficient diet > SHR fed a standard diet. Administration of the nitric oxide synthase (NOS) inhibitor, L-NAME, caused an increase in MAP levels in the two groups of rats, demonstrating the involvement of the vasodilator, nitric oxide (NO), in the regulation of systemic BP in a genetically hypertensive state. The expression of endothelial (e) NOS mRNA and protein in the thoracic aorta paralleled basal MAP levels in the two groups of rats, suggesting the counter-regulation of eNOS against the developed hypertensive state in SHR fed a Zn-deficient diet. On the other hand, administration of the superoxide scavenger, tempol (a SOD mimetic compound), led to a decrease in MAP levels in the two groups of rats, indicating the participation of the oxygen free radical, superoxide, in an increase in systemic BP in a genetically hypertensive state. As reported recently, the mechanism involved is due likely to a decrease in the action of the vasodilator, NO, based on the formation of peroxynitrite coming from the non-enzymatic reaction of superoxide and NO. In addition, tempol treatment completely restored MAP levels in SHR fed a Zn-deficient diet to levels comparable to those observed in SHR fed a standard diet, indicating that a further increase in systemic BP levels seen in SHR fed a Zn-deficient vs. a standard diet is presumably brought by a reduction in the action of the vasodilator, NO, resulting from an increase in the action of superoxide. The activity of the superoxide scavenger, Cu/Zn-SOD, in the thoracic aorta was significantly decreased in SHR fed a Zn-deficient diet relative to SHR fed a standard diet. It appears that a decrease in the activity of Cu/Zn-SOD observed in the thoracic aorta of SHR fed a Zn-deficient diet at least in part plays a role in an increase in the action of superoxide in this model. Thus, Zn deficiency may be a factor to develop genetic hypertension presumably through the oxidative stress caused by superoxide.

We have studied the critical properties of the contact process on a square lattice with quenched site dilution by Monte Carlo simulations. This was achieved by generating in advance the percolating cluster, through the use of an appropriate epidemic model, and then by the simulation of the contact process on the top of the percolating cluster. The dynamic critical exponents were calculated by assuming an activated scaling relation and the static exponents by the usual power law behavior. Our results are in agreement with the prediction that the quenched diluted contact process belongs to the universality class of the random transverse-field Ising model. We have also analyzed the model and determined the phase diagram by the use of a mean-field theory that takes into account the correlation between neighboring sites., 14 pages and 8 figures

This paper presents a simple method to measure the relative permittivity of glass-epoxy printed circuit boards (PCBs). In this method, the relative permittivity as a function of frequency is measured using an actual PCB. In order to estimate the relative permittivity, the reflection coefficient is measured with a network analyzer. The relative permittivity is calculated by observing the frequencies of the resonant cavity modes. We show that the relative permittivity of an FR-4 sample decreases from 4.3 to 4.2 at frequencies from 300 MHz to 2 GHz.

We propose a novel ultrafast (instantaneous response), low-power, and simple demultiplexer for optical time-division multiplexed signals. It requires no ultrafast optical devices such as all-optical gates or electroabsorption modulators. Only a power combiner and a dispersive medium are required as optical components, thus making the system very simple. Furthermore, the separation of control pulses is not required, which also helps to simplify the system. A design optimization in terms of the signal-to-noise ratio was performed, and equations that provide design parameters were derived. The effect of the wavelength fluctuation and the timing jitter of signal pulses were evaluated based on a numerical analysis, which indicated that this demultiplexer shows a small bit error rate (

A novel dataline redundancy suitable for an embedded DRAM macro with wide data bus is presented. This redundancy reduces the area required for spare cells from 6 to 1.6% of the area required for normal cells and improves chip yield from 50 to 80%. In addition, it provides a high-speed data path. An embedded DRAM macro adopting the redundancy achieves 200-MHz operation and provides 51.2-Gbit/s bandwidth. It has been fabricated with 0.25-/spl mu/m technology.

Compact semiconductor-based ultrafast optoelectronic devices are crucial for networks with a throughput in the 1–10 Tb/s range. A variety of ultrafast phenomena in semiconductors are attractive for developing such new optoelectronic devices. This paper discusses the requirements of ultrafast optical-communication systems and necessary optoelectronic devices. Recent progress of ultrafast semiconductor-based optoelectronic devices are described with a focus on all-optical switching devices, including novel devices using electron spin polarization relaxation and intersubband transition both in multiple quantum well structures.

We investigate the transient absorption characteristics of interband (IB) transitions influenced by an intersubband (ISB) control light in an undoped quantum well system with both the coupling light fields in pulsed form. The effect of the dephasing rate of the system and the ISB control pulse characteristics on the IB absorption are investigated. The temporal overlap of the control and the signal light pulses affecting the transient IB absorption are also studied. It is observed that the optical modulation by the control light field depends significantly on the detuning of the signal light from the resonant IB transition energy.

This DRAM macro is suitable for a memory generator implementation. The article shows the expandable floor layout scheme (EFLS) of the DRAM macros. A macro architecture that consists of several banks has a disadvantage that the macro size becomes large, because each bank has peripheral circuits for independent operation. The EFLS eliminates this redundancy by sharing the peripheral circuits among the expansion units of the memory array. Two types of floor layouts are supported by EFLS. One is simple I/O type. The other is doubled I/O type. In both of the arrangements, a DRAM macro is formed by combination of 1 Mb memory array segments and peripheral blocks. Each block is manually designed so the macro size is minimized when all the blocks are combined together. Peripheral circuits that can be shared among 1 Mb segments are placed in the peripheral blocks to save the area.

Effects of lithium (Li) deficiency and/or immobilization stress on the thymus weight and differential blood count of rats were studied. The thymus weight of the rats fed a low Li diet were lighter than those of rats fed a Li supplemented diet, whether the rats were exposed to stress or not. Of the rats not exposed to stress, those in the low Li diet group showed a significant decrease in the ratios of neutrophiles and T helper lymphocytes. However, there was an increase in the total number of lymphocytes in the low Li dietary group. It was shown that Li deficiency altered the responses to stress in rats.

Introduction There is a growing interest in the use of patient-reported outcomes to provide a more patient-centered view on treatment. Forgetting the artificial joint can be regarded as the goal in joint arthroplasty. The goals of the study were to describe changes in joint awareness in the artificial joint after total knee arthroplasty (TKA), and to determine which factors among pain, knee range of motion (ROM), quadriceps strength, and functional ability affect joint awareness after TKA. Hypothesis Patients undergoing TKA demonstrate changes in joint awareness and joint awareness is associated with pain, knee ROM, quadriceps strength, and functional ability. Patients and methods This prospective cohort study comprised 63 individuals undergoing TKA, evaluated at 1, 6, and 12 months postoperatively. Outcomes included joint awareness assessed using the Forgotten Joint Score (FJS), Pain Score, knee ROM, quadriceps strength, and functional ability. Results Fifty-eight individuals completed all postoperative assessments. All measures except for knee extension ROM improved from 1 to 6 months. However, there was no difference in any measure from 6 to 12 months. FJS was affected most greatly by pain at 1 month and by quadriceps strength at 6 and 12 months. Discussion Patients following TKA demonstrate improvements in joint awareness and function within 6 months after surgery, but reach a plateau from 6 to 12 months. Quadriceps strength could contribute to this plateau of joint awareness. Level of evidence Prospective cohort study, IV.

It is important to manage precise power flows in closed small power networks for their reliable operations. This paper describes a method for managing the instantaneous power flows in a local area power network. In order to provide instantaneous power to a load through a power bus without disturbing the other modules, we adaptively adjust the power flow and keep the balance of the instantaneous power. As a tool of the balancing, we use power flows based on Tellegen's theorem and Kirchhoff's voltage law to determine the network states uniquely. Index Terms--Instantaneous power, Power balancing, Power flow, Tellegen's theorem

Magnetic semiconductor GdN thin film has been studied by a conventional X‐band electron spin resonance (ESR). Electron paramagnetic resonance (EPR) of GdN is observed at 100 K while the ferromagnetic resonance (FMR) is clearly observed at 4.2 K, which is confirmed by the typical angular dependence of FMR. The result will be discussed in connection with the magnetic properties obtained previously by our SQUID magnetometer measurement.

The use of optical interconnections between processors, boards, chips, and gates in electronic digital systems to overcome the current performance limitations is described. The advantages of optical interconnections in relation to the interconnection distance, the data capacity, and the interconnection functions are presented. The devices which will support practical implementation of optical interconnections and the integration of optical interconnection devices are discussed. The development of future integrated optoelectronic materials, processing, and fabrication technologies to support integrated optical electronics is also discussed. >

We studied the effect of increased afterload on the ratios of O2 consumption (VO2) to external work (EW), VO2 to the systolic pressure-volume area (PVA), and PVA to EW at control state and with dobutamine in the left ventricles of open-chest dogs. Left ventricular volume was measured with a volumetric conductance catheter and coronary flow with an electromagnetic flowmeter. Hexamethonium bromide and atropine sulfate were administered before changes in end-systolic pressure (Pes) with an infusion of nitroprusside or angiotensin II. Dobutamine enhanced ventricular end-systolic elastance by 100%. In the control, with increases in Pes, EW/VO2 remained unchanged, PVA/VO2 increased by 48%, and EW/PVA decreased by 26%. Dobutamine increased both EW/VO2 and EW/PVA at any given Pes but decreased PVA/VO2. During dobutamine, EW/VO2 increased significantly with increases in Pes. The ratio of measured EW/VO2 to the theoretically predicted maximal EW/VO2 value for a given end-diastolic volume and contractility was 0.83 at a Pes of 70 mmHg, and this ratio decreased by 33% with increases in Pes in the control. During dobutamine, measured EW/VO2 values were almost equal to each corresponding theoretical maximal value, and the average decrease in the ratio with increases in Pes was 7%. Thus the enhanced inotropic state by dobutamine can restore the afterload-induced deterioration of EW/VO2 toward the normal maximal level.

The performance of high-value-added synthetic-fiber products is greatly affected, not only by the properties of the polymer itself, but also by the fiber form and the structure of yarns and fabrics made from the fiber, which can be controlled for particular uses. This paper deals primarily with polyester-fiber fabrics in general, from the viewpoint of the classification of the shape of fibers, which is characterized by the cross-section and surface configuration, and secondly with products characterized by the mutual interactions between the fiber form and the structure of fiber assemblies, such as silk-like fabric, spunize fabric, sweat-absorption polyester-fiber fabric, brilliant-color-developing polyester-fiber fabric, pile fabric, wiping cloth, tickproof quilt covers, and so forth. Finally, some products developed in imitation of the structure and functions of natural fibers are described to indicate a number of directions yet to be taken by synthetic-fiber fabrics. For the development of new high-val...

A new method of mode analysis of multimode microwaves in an oversize waveguide is developed which utilizes infrared camera images of the radiation profile of microwaves launched from the waveguide end. Systematic variations of the radiation pattern with different phase shifts among constituent modes are compared with theoretical predictions to identify the constituent modes and to determine their fraction of power. Characteristics of a step‐wise modulated TE02–TE01 mode converter are examined by using this method. It is demonstrated that this method is useful as a practical means for on‐site analysis of waveguide properties.

This paper reports numerical and experimental analyses of a stepwise modulated TEon mode converter based on the mode‐matching formulation. By systematic analyses, the dimensions of the TE02 to TE01 converter at 41 GHz are optimized so that a power conversion efficiency higher than 99.3% is theoretically obtained with a reflection coefficient less than 0.2%. The simple structure of the converter not only allows easy manufacturing with ordinary machining but it also enables the converter characteristics to behave well and be readily adjusted on the laboratory site. Based on the numerical analyses, a mode converter is designed and fabricated for use in the ECRH experiment on the GAMMA 10 tandem mirror. Preliminary tests show that the converter works well at a high power, above 100 kW. The transmittable power is limited by external nonaxisymmetric modes which can eventually be suppressed with efficient mode filters.

A Ba2YCu3O7−y high Tc superconductor degrades with time in air. In this paper we discuss the early stage of the degradation from a microscopic standpoint by using transmission electron microscopy (TEM). It has been shown by a high resolution TEM that the degradation has two modes. One is the formation of amorphous and polycrystalline phases, the latter of which are perhaps BaCO3. It has been clarified that the origin of the formation of the amorphous and polycrystalline phases is the reaction of Ba2YCu3O7−y phase with the water vapor, and the polycrystalline phase is formed sequentially after the formation of the amorphous phase. The other is the formation of planar defects which are introduced between Ba‐O and Ba‐O layers even in dry air. It is thought that the planar defects are formed to relax the strain energy of the dislocation caused by the migration of ions.

California has several health insurance programs for children. However, the system for enrolling into these programs is complex and difficult to manage for many families. Express Lane Eligibility is designed to streamline the Medicaid (called Medi-Cal in California) enrollment process by linking it to the National School Lunch Program. If a child is eligible for free lunch and the parents consent, the program provides two months of presumptive eligibility for Medi-Cal and a simplified application process for continuation in Medi-Cal. For those who are ineligible, it provides a referral to other programs. An evaluation of Express Lane shows that while many children were presumptively enrolled, nearly half of the applicants were already enrolled in Medi-Cal. Many Express Enrolled children failed to complete the full Medi-Cal enrollment process. Few were referred to the State Children's Health Insurance Program or county programs. Express Lane is less useful as a broad screening strategy, but can be one of many tools that communities use to enroll children in health insurance.

We have been developing an LSI model for EMC simulation in electronic control units. EMI simulations have been applied to some units using an LSI EMI model. These models have been called the LECCS Model and ICEM Model, but there are few examples of EMS simulation in printed circuit boards. Therefore , we studied the LSI EMS model and attempted to perform an EMS simulation of a printed circuit board. The LSI was tested through the DPI method (IEC61967-4). The EMS in this test system was analyzed, and the usefulness of this method of analysis was confirmed. The analysis was also applied to a product.

Highly sensitive control of anisotropic optical polarization in CdMnTe quantum wires has been studied theoretically using multi-band effective mass method. A magnetic field dramatically changes the transition probability via the sp-d exchange interaction.

Electron transfer between different redox molecules was studied using Langmuir-Blodgett (LB) muitiiayers. Porphyrin and flavin LB multilayers were deposited on a gold electrode to form a flavin-porphyrin heterojunction and the cyclic voltammograms were analyzed with a developed model of cyclic voltammetry. The electron transfer from flavln to porphyrin is found to be much faster than from porphyrin to flavin. Also as the first step to address a singieelectroactive LB molecule, the structure of the flavin LB monolayer was studied using scanning tunneling microscope (STM) and transmission electron microscope (TEM). The monolayer has fibrous structure. Flavin ring could be also identlfied.

A test flow using a auto repair technique has also been proposed. It assumes a conventional wafer testing, but puts much weight on the post-package test by utilizing the proposed auto repair technique. This is implemented in a 36 Mb embedded DRAM macro of 6ns cycle time. It consists of internal compare circuit, redundancy analyzer, and anti-fuses. The internal auto programming of anti-fuse fixes post-packaging failures that might appear by final at-speed test and contributes to yield improvement.

We have investigated spontaneously accumulated two‐dimensional electrons at the long‐range ordered Ga0.5In0.5P/GaAs interface as a function of the order parameter. Raman‐scattering and photoluminescence measurements reveal that the accumulated electron density and interface built‐in electric field depend systematically on the order parameter. These results agree well with self‐consistent calculations taking into account electronic band structure with the two‐dimensional electrons.

In this paper, we review some of the progresses in quantum- and nano-structure semiconductor devices with a particular focus on femtosecond all-optical switches based on intersubband transition in quantum wells (QWs) and ultrafast quantum dot semiconductor optical amplifiers (QD-SOAs).

A wind velocimeter using scintillation of the laser beam has been developed for a portion of a gas flux monitor, which has been modified common eddy correlation method. The velocimetry system shares the laser beam with a laser absorption spectrometry (LAS) system and can obtain the wind velocity in the quite same location that the LAS system monitors gas density. To confirm the performance of the velocimetry system under the natural condition, some outdoor experiments were carried out to monitor upward current of air. In this paper, some results of outdoor experiments are demonstrated.

Ultrafast optoelectronic devices are crucial for fulfilling the future requirement of network throughput to enter the 1 Tb/s to 10 Tb/s range. A variety of ultrafast phenomena in InP-based semiconductors are attractive for developing such new optoelectronic devices. This paper discusses the requirements of ultrafast optical communication and signal-processing systems and devices necessary for them. Recent advances in the development of ultrafast semiconductor-based optoelectronic devices, such as ultrashort pulse lasers and ultrafast all-optical switches, are described,.

This paper describes a design technique of decoupling circuits that can reduce high frequency current rushing into the power/ground planes of a digital PCB. In this technique, the IC is modeled as a current source of high frequency, and a parameter that represents the effect of the high frequency current reduction is derived. Then, by using the parameter, a design procedure to obtain the optimal bypass capacitor and the decoupling inductor is shown. Furthermore, validity of this modeling is shown by experimental study.

The authors report a detailed determination of the structure of damage formed by CH/sub 4/-RIE (reactive ion etching) of InP, using a combination of three different characterization techniques for chemical, physical, and optical properties. X-ray photoelectron spectroscopy (XPS) and Rutherford back scattering (RBS) techniques were employed for the characterization of the chemical and physical structure of the damage. Photoluminescence (PL) measurement was performed at 4.2 K for optical characterization. The results obtained demonstrate the layered structure of the damage and also indicate the recovery of optical damage due to hydrogen passivation and high-temperature annealing. >