A 6 K-gate GaAs gate array with a new large-noise-margin SLCF circuit

Hot-carrier (HC) degradation phenomena in p-channel lightly doped drain (LDD) MOSFETs and the effects of an LDD structure in minimizing HC degradation are described. Hot-electron injection in p-channel LDD MOSFETs causes effective channel length shrinkage. This phenomenon is also observed in conventional p/sup +/-drain MOSFETs but differs greatly from that in n-channel LDD MOSFETs. This is because hot electrons trapped in gate SiO/sub 2/ accumulate carriers (holes) along the channel region near the drain and decrease the pinchoff region. On the other hand, the LDD region in p-channel MOSFETs reduces HC generation to one-tenth of that in p/sup +/-drain MOSFETs under the same applied voltage. Moreover, the lifetimes of the LDD MOSFETs defined as how long it takes the transconductance deviation to reach 10% are longer by two orders of magnitude than those of the p/sup +/-drain MOSFETs under the same HC generation conditions. To obtain the best lifetime, it is shown that the optimum boron dose in the LDD region is between 1 and 3*10/sup 13/ cm/sup -2/. >

VLSI computing is critical in chip fabrication in today's digital age. Moore's law demands that "the number of transistors on a microchip doubles every two years" in addition to that "the count of transistors employed in a chip size is reduced". As a result, this rule is dictating the electronics industry by reducing chip area, size, and power consumption while simultaneously enhancing chip fabrication strength. The arithmetic circuits are constructed in this work, by boosting the efficiency of circuits by considering die space as a constraint. Overall, arithmetic circuits have a bunch of usages in processing architecture. The XOR gate and multiplexer are utilized in this study to make compressor circuits more efficient by taking into account area, power, and delay. To examine the arithmetic circuit's performance, the load capacitance is customized and the power dissipation across the capacitor is studied.

A guideline for n/sup /spl minus// fully gate overlapped (FOLD) structure design optimization has been studied. From the viewpoint of reliability, the greatest reduction in substrate current directly leads to the most reliable n/sup /spl minus// design for the FOLD structure. The current path modulation phenomenon due to the trapped charge at the n/sup /spl minus// extension region dominates the hot-carrier induced characteristics change for conventional lightly doped drain (LDD) structure with side-wall spacer. This phenomenon is minimized in the FOLD structure due to its higher controllability of the gate electrode than the LDD structure at the n/sup /spl minus// extension region. Furthermore, it was also confirmed that the 0.3 /spl mu/m optimized FOLD structure can achieve high circuit performance at 3.3 V operation, maintaining hot-carrier resistance. >

Optimization of the n/sup -/ region concentration for n-channel MOSFET's with a lightly doped drain (LDD) structure was investigated, based on an analysis of the substrate current characteristics. When a substrate current tailing is observed, which is peculiar to the LDDFET with a low-concentration n-region, a gate current is not observed, which suggests strong resistance against hot-carrier injection. This was confirmed by a bias stress test. The optimized surface concentration for the n/sup -/ region ranges from 1 x 10/sup18/ cm/sup -3/ to 2.5 X 10/sup 18/ cm/sup -3/ under negligible V/sub TH/ shift and less than 25-percent driving capability degradation, compared to values for a conventional MOSFET.

PurposeThe existence of the advertising delay effect and its impact on supply chain operations have been demonstrated in the current study. Therefore, this study develops a timely inventory control strategy for the fresh produce supply chain to address the advertising delay effect in the fresh produce supply chain.Design/methodology/approachThis study proposes a game model based on the Nerlove-Arrow time delay differential equation and Pontryagin's maximum principle. Through comparative analyses of the optimal equilibrium strategies, the authors compare the optimal equilibrium strategies, product goodwill and optimal inventory trajectories for suppliers and retailers under secondary replenishment decisions and decentralized decisions.FindingsThe authors find that (1) Only when the sales cycle meets certain conditions can the overall profit of the supply chain under the secondary replenishment decision be greater than that under the decentralized decision. As the price markup coefficient increases, the total profit of the supply chain first increases and then decreases. (2) With the increase in the delay time, the replenishment quantity during the initial period gradually decreases. After the delay time elapses, the inventory depletion rate under secondary replenishment decisions is faster than that under decentralized decision-making. (3) Although there is a continuously increasing maximum value of product goodwill with the increase in delay time, it becomes difficult to achieve this value for longer delays.Practical implicationsThe authors’ findings provide a theoretical basis for supply chain members of fresh agricultural products to select replenishment and inventory control strategies when adopting different levels of delay in advertising marketing.Originality/valueFirstly, this paper explains the impact of advertising delay effect on fresh produce supply chain from a dynamic perspective, and secondly, it provides guidance on advertising formulation and inventory replenishment for fresh produce retailers under the influence of advertising delay effect.

On June 8, 2008, at 12:25 GMT, a M W 6.4 earthquake, the Movri Mountain earthquake, occurred in the area of northwest Peloponnese, western Greece. The epicenter was located in the municipality of Movri, 35 km southwest of Patras. For this study, a crustal anisotropy analysis was performed in the epicentral area of the Movri Mountain earthquake. Specifically, the shear-wave splitting phenomenon and its temporal evolution in relation to the Movri Mountain earthquake was studied, using the cross-correlation method. The data analysis revealed the presence of shear-wave splitting in the study area. Both before and after the Movri Mountain earthquake, the polarization directions of the fast component of the shear waves followed a general NNW-SSE direction. The observed mean fast polarization direction was not consistent with the regional stress field, which showed a general E-W direction of the maximum horizontal compressive stress. The differences between the estimated fast polarization directions and the properties of the regional stress field suggest the presence of a local stress field in the area around the fault. An increase in time delays was observed soon after the Movri Mountain earthquake. The average value of the delay times before the earthquake was ca. 18 ±2.6 ms, while after the earthquake this was ca. 40 ±4.6 ms. This increase in the time delay indicates changes in the crustal properties, which were possibly caused by variations in the preexisting micro-crack system characteristics related to the Movri Mountain earthquake, and the possible involvement of over-pressured fluids.

510 Background: In treatment of rectal adenocarcinoma, an increased time delay (TD) of 6-12 weeks from the end of radiation therapy to surgery may increase the rate of complete pathologic response (pCR), but the optimal TD with respect to survival has not been established. This study evaluates the impact of TD on overall mortality. Methods: The NCDB was queried for patients with adenocarcinoma of the rectum and no evidence of metastasis at diagnosis, who underwent preoperative chemoradiation followed by radical surgical resection. Standard statistical methods were employed for descriptive statistics and Cox model development. Results: The study included 6805 patients, predominantly Caucasian (87.2%) and males (63.9%) who generally were treated with low anterior resection (57.3%), colonanal reanastomosis (8.4%), or abdominoperineal resection (28.4%), and had median survival of 66.6 months. The effects of age, surgical margins (-/+), comorbidity index, time to discharge after surgery, TMN pathologic staging, surgical volume, and patient income significantly impacted mortality after radiation and surgery (p<0.05 for all values). There was a significant relationship between TD and pCR (p=.0002). At TD less than 30 days, 4.0% of patients achieved pCR, while 9.3% of patients have achieved pCR by 75 days. In TD of greater than 75 days, the rate of pCR decreased. Overall, 6.8% of patients (n=461) achieved pCR. Using a refined cox model, a TD of more than 60 days was associated with 20% greater risk of mortality (95% CI 1.068 – 1.367). This effect became more pronounced with increasing TD; a TD of greater than 75 days was associated with 28% (95% CI 1.06-1.55) increased risk of mortality, while patients with TD less than 60 days saw a survival benefit. Conclusions: Though an interval up to 75 days between radiation and surgery may achieve higher rates of complete pathologic response, delay of more than 60 days from radiation to surgical resection and subsequent systemic chemotherapy decreases overall survival in patients with rectal cancer.

This paper presents the stability and bifurcation of the Hindmarsh–Rose neuronal model with time delay. First, we discuss the existence and stability of the equilibria, revealing that the system can have a maximum of three equilibria which exhibit always stable, always unstable, and stability switching dynamics, depending on the stability of the equilibria when there is no time delay. Furthermore, an explicit formula for the time delay at which Hopf bifurcation occurs is derived, and the direction and stability of the Hopf bifurcation are also given. Finally, numerical simulations are carried out to support our theoretical results. We find that due to the existence of time delay, our system can exhibit many interesting dynamical behaviors depending on the number of equilibria and the increase in time delay. For instance, with increasing time delay, bistability transitions to the coexistence of a periodic solution and a stable equilibrium, followed by the emergence of quasi-periodic motion alongside stable equilibria, and eventually leading to chaotic motion coexisting with a stable equilibrium.

In this paper, we establish a stochastic dynamical grazing ecosystem with time delays and fluctuations. The effects of time delay, Gaussian noise and Lévy noise on the stationary probability distribution (SPD), the mean first passage time (MFPT) and stochastic resonance (SR) are analyzed. Our research results show the following: (i) For small time delay, the increasing Gaussian noise intensity leads to catastrophic regime shift (CRS) from high vegetation state to low vegetation state, while the increasing Lévy noise intensity contributes to the recovery of these shifts. For large time delay, the increasing Gaussian noise intensity or Lévy noise intensity causes the CRS phenomenon, the larger the time delay, the more frequent the CRS phenomenon. (ii) The increasing Gaussian noise intensity can diminish the stability of the high vegetation state and low vegetation state, the increasing Lévy noise intensity and Lévy stability index can enhance the stability of the high vegetation state and diminish the stability of the low vegetation state. The increasing Lévy noise intensity can lead to noise-enhanced stability (NES) of the high vegetation state, and the larger the time delay, the more pronounced the NES phenomenon. (iii) The increase of time delay can weaken SR phenomenon when signal-to-noise ratio (SNR) is a function of Gaussian noise intensity and Lévy noise intensity.

Previous studies have shown that epithelial Na+ channels (ENaCs) are activated by laminar shear stress (LSS). ENaCs with a high intrinsic open probability because of a mutation (betaS518K) or covalent modification of an introduced Cys residue (alphaS580C) in the pre-second transmembrane domain (pre-M2) were not activated by LSS, suggesting that the pre-M2 region participates in conformational rearrangements during channel activation. We examined the role of the pore region of the alpha-subunit in channel gating by studying the kinetics of activation by LSS of wild-type ENaC and channels with Cys mutations in the tract Ser576-Ser592. Whole cell Na+ currents were monitored in oocytes expressing wild-type or mutant ENaCs prior to and following application of LSS. Following a 2.2-s delay, a monoexponential increase in Na+ currents was observed with a time constant (tau) of 8.1 s in oocytes expressing wild-type ENaC. Cys substitutions within the alpha-subunit in the tract Ser580-Ser589 resulted in: (i) a reduction (Ser580-Trp585, Gly587) or increase (Ser589) in delay times preceding channel activation by LSS, (ii) an increase (Gln581, Leu584, Trp585, Phe586, Ser588) or decrease (Ser589) in the rate of channel activation, or (iii) a decrease in the magnitude of the response (Ser583, Gly587, Leu584). Cys substitutions at a putative amiloride-binding site (alphaSer583 or betaGly525) or within the selectivity filter (alphaGly587) resulted in a reduction in the LSS response, and exhibited a multiexponential time course of activation. The corresponding gamma-subunit mutant (alphabetagammaG542C) had a minimal response to LSS and exhibited a high intrinsic open probability. These data suggest that residues in the pore region participate in the sensing and/or transduction of the mechanical stimulus that results in channel activation and are consistent with the hypothesis that the ENaC pore region has a key role in modulating channel gating.

Impact of time delay on population model with Allee effect

<p>Seismic anisotropy across the Hikurangi subduction zone measured from shear-wave splitting exhibits strong lateral changes over distances of about 250 km. Teleseismic S-phases show trench-parallel fast polarisations with increasing delay times across the forearc and arc region. In the arc region, delay times reach up to 4.5 s, one of the largest delay times measured in the world. Such large delay times suggest strong anisotropy or long travel paths through the anisotropic regions. Delay times decrease systematically in the backarc region. In contrast, local S-phases exhibit a distinct change from trench-parallel fast orientations in the forearc to rench-perpendicular in the backarc, with average delay times of 0.35 s. In the far backarc, no apparent anisotropy is observed for teleseismic S-phases. The three different anisotropic regions across the subduction zone are interpreted by distinct anisotropic domains at depth: 1) In the forearc region, the observed "average" anisotropy (about 4%) is attributed to trench-parallel mantle flow below the slab with possible contributions fromanisotropy in the slab. 2) In the arc region, high (up to 10%) frequency dependent anisotropy in the mantle wedge, ascribed to melt, together with the sub-slab anisotropy add up to cause the observed high delay times. 3) In the far backarc region, the mantle wedge dynamic ends. The apparent isotropy must be caused by different dynamics, e.g. vertical mantle flow or small-scale convection, possibly induced by convective removal of thickened lithosphere. The proposed hypothesis is tested using anisotropicwave propagation in two-dimensional finite difference models. Large-scale models of the subduction zone (hundreds of kilometres) incorporating the proposed anisotropic domains of the initial interpretation result in synthetic shear-wave splittingmeasurements that closely resemble all large-scale features of real data observations across the central North Island. The preferred model constrains the high (10%) anisotropy to the mantle wedge down to about 100 kmunder the CVR, bound to the west by an isotropic region under the western North Island; the slab is isotropic and the subslab region has average (3.5%) anisotropy, down to 300 km. This model succeeds in reproducing the constant splitting parameters in the forearc region, the strong lateral changes across the CVR and the apparent isotropy in the far backarc region, as well as the backazimuthal variations. The influence of melt on seismic anisotropy is examined with different small-scale (tens of kilometres) analytical modelling approaches calculating anisotropy due to melt occurring in inclusions, cracks or bands. Conclusions are kept conservative with the intention not to over-interpret the data due to model complexities. The models show that seismic anisotropy strongly depends on the scale of inclusions and wavelengths. Frequency dependent anisotropy for local and teleseismic shear-waves, e.g. for frequency ranges of 0.01-1Hz can be observed for aligned inclusions on the order of tens of meters. To test the proposed frequency dependence in the recorded data, two different approaches are introduced. Delay times exhibit a general trend of -3 s/Hz. A more detailed analysis is difficult due to the restricted frequency content of the data. Future studies with intermediate frequency waves (such as regional S-phases) are needed to further investigate the cause of the discrepancy between local and teleseismic shear-wave splitting. An additional preliminary study of travel time residuals identifies a characteristic pattern across central North Island. Interpretation highlights the method as a valuable extension of the shear-wave splitting study and suggests a more detailed examination to be conducted in future.</p>

We investigated the lifetimes for various poly-Si thin film transistor (TFT) structures. A gate-overlapped lightly doped drain (GOLDD) structure was self-aligned by the side etching of Al-Nd in an Al-Nd/Mo gate electrode. The dopant activation process in the LDD regions of GOLDD TFTs was performed by using a H/sub 2/ ion-doping technique. We also observed the effect of lifetime on the source/drain activation process. The thermal annealing of the source/drain region was found to extend the lifetime. The predicted lifetime of our GOLDD poly-Si TFT is superior to those of non-lightly doped drain (non-LDD) and lightly-doped drain (LDD) poly-Si TFTs. The trapped-electron density at the drain junction after bias-stressing was also investigated using a two-dimensional (2-D) simulation.

Since time delays are very vital and inevitable in the transmission of neurons, this paper is mainly concerned with the dynamic analysis of the magnetic flux e-HR neuron model with time delays. Specifically, the stability of the system at the equilibrium point and the conditions for bifurcations are analyzed to explore the impact of time delays on dynamics behavior. Results show that the system exhibits Hopf bifurcation within the specific range of time delay. Moreover, the increase of time delay can induce the tip discharge behavior. In addition, we investigate the stability and bifurcation behavior of the model with dual time delays. Our results indicate that the system displays rich dynamics performance under certain conditions. Furthermore, numerical simulations show time delays play a crucial role in the dynamics process for the magnetic flux e-HR neuron model.

One of the crucial issues in ecology is related to algal bloom in lakes. Vast amount of efforts has been channeled to combat this problem, but for successful implementation of any algae eradication effort, their impact on the dynamics of water body must be studied explicitly. In view of this, we propose and analyze a mathematical model to assess the effect of applying efforts for removal of algae and detritus from a lake on the occurrence of algal bloom. The system is governed by the interactions of four variables, namely, concentration of nutrients, density of algae, density of detritus and efforts applied to remove algae as well as detritus from the lake. The biologically feasible equilibria and their stability properties are analyzed and discussed. Considering the growth rate of applied efforts as time dependent, we also obtain the optimal control strategy to minimize both the algae and the associated costs. The optimality system is derived and solved numerically. Further, to make the system more realistic, two discrete time delays; one in conversion of detritus into nutrients and other in applying the control efforts are considered. We study various cases for the time delays and show that in general the system develops limit cycle oscillation through a Hopf-bifurcation for increasing time delays. However, we observe that in some cases, increase in time delays may diminish the oscillations. Our results indicate that high concentration of nutrient intensifies the occurrence of algal bloom and in that case applied efforts play a pivotal role in reducing the bloom.