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Michelson interferometer modulators (MIMs) have superior modulation efficiency but shortcomings in high-frequency performance. We combine broadband technologies, the inductive and T-coil peaking technologies, with folded Michelson interferometer modulators (FMIMs) to make the device footprint more compact and improve the bandwidth of these modulators. A series of FMIMs are explored with different additional electric structures and electrode distribution with only 250-μm modulation areas. The on-chip insertion loss is about 1.22 dB for all FMIMs. Under 2 V reverse bias, the calculated Vπ-Ls of the modulators with GSG and GS electrodes are 0.933 V·cm and 1.284 V·cm. Both broadband technologies can enhance the high-frequency performances of FMIMs. The measured electro-optical (EO) bandwidths can reach 28.4 GHz for inductive peaking FMIMs at −6 V bias, which is 44 GHz for T-coil peaking at –2 V. The T-coil peaking FMIMs with the GSG lumped electrode (LE) and a 30-ohm terminal resistor can achieve a better trade-off between various performances with the clearer eye diagrams of 60 GBaud 4-level pulse amplitude Modulation (PAM4) and 60 Gbps On-Off Keying (OOK).

Highly Pr-doped Ba2In2O5 (PBI) was successfully fabricated and its ionic conduction and power generation characteristics were studied in this work. Two PBI materials of different concentration ratio were evaluated: Pr:Ba:In = 0.9:1.1:1 (PBI910) and Pr:Ba:In = 1:1:1 (PBI000). PBI910 material was confirmed as single phase with cubic perovskite structure. However, PBI000 had both cubic phase and impurity phase. In a hydrogen concentration cell, the measured proton transfer number of PBI910 at 500degC was 0.81 and then decreased with increasing temperature, whereas the oxide ion transfer number was 0.07 and then increased with increasing temperature. Power generation experiments were evaluated at 500degC to 900degC using PBI as electrolyte and H2 as fuel. Results revealed that and showed different dependency on temperature and significantly affected the power density. Proton conduction dominated from 500degC[?]600degC, and power density increased with increasing operating temperature due to improved proton conductivities. However, at 600[?]800degC, proton conductivities decreased, which caused a decrease in power density. Further increase in temperature into the 800degC[?]900degC range showed oxide ion conduction to then dominate, and the consequent improved oxide ion conductivity again increased the power density despite a decrease in open current voltage (OCV).

Rechargeable Direct Carbon Fuel Cells (RDCFCs) use deposited pyrolytic carbon as fuel. With a batch-type charging system, the change in the amount of deposited carbon as a function of pyrolysis time was monitored in order to estimate the optimal pyrolysis time and to improve the propane-based fuel utilization. When the pyrolysis time was 5 min, the propane-based fuel utilization efficiency of RDCFCs was improved from 3% to 35% at a power density between 60-80 mW/cm2 compared to previous RDCFCs. The improvement was due to a high conversion rate to carbon (73%) from propane to solid carbon caused by longer pyrolysis time. The effects of hydrogen in RDCFC power generation were also investigated because in the pyrolysis of hydrocarbon, hydrogen is also produced. Results indicate that existence of hydrogen seems to promote the utilization of solid carbon.

We present a wave generalization of the classic Schwarzschild method for constructing self-consistent halos--such a halo consists of a suitable superposition of waves instead of particle orbits, chosen to yield a desired mean density profile. As an illustration, the method is applied to spherically symmetric halos. We derive an analytic relation between the particle distribution function and the wave superposition amplitudes and show how it simplifies in the high-energy (WKB) limit. We verify the stability of such constructed halos by numerically evolving the Schrödinger-Poisson system. The algorithm provides an efficient and accurate way to simulate the time-dependent halo substructures from wave interference. We use this method to construct halos with a variety of density profiles, all of which have a core from the ground-state wave function, though the core-halo relation need not be the standard one. [ABSTRACT FROM AUTHOR]

Recently, digital twins (DTs) have become a research hotspot in smart manufacturing, and using DTs to assist defect recognition has also become a development trend. Real-time data collection is one of the advantages of DTs, and it can help the realization of real-time defect recognition. However, DT-driven defect recognition cannot be realized unless some bottlenecks of the recognition models, such as the time efficiency, have been solved. To improve the time efficiency, novel defect class recognition is an essential problem. Most of the existing methods can only recognize the known defect classes, which are available during training. For new incoming classes, known as novel classes, these models must be rebuilt, which is time-consuming and costly. This greatly impedes the realization of DT-driven defect recognition. To overcome this problem, this paper proposes a deep lifelong learning method for novel class recognition. The proposed method uses a two-level deep learning architecture to detect and recognize novel classes, and uses a lifelong learning strategy, weight imprinting, to upgrade the model. With these improvements, the proposed method can handle novel classes timely. The experimental results indicate that the proposed method achieves good results for the novel classes, and it has almost no delay for production. Compared with the rebuilt methods, the time cost is reduced by at least 200 times. This result suggests that the proposed method has good potential in the realization of DT-driven defect recognition.

One-dimensional and two-dimensional Laser Doppler Velocimeter (LDV) were used respectively to measure velocity of smooth-wall open channel flows with channel bed slopes varying between 0.25% and 3%. Turbulent flows were all supercritical with Froude numbers varying from 1.5 to 3.5 and Reynolds number having a magnitude of 105. Using 1-D LDV the law of the wall and the law of the wake were examined and the von Karman constant K was verified to be 0.4 universally, while the integral constant A might change with distance from the side wall. The law of the wake exists clearly with a wake strength Π of about 0.3. Moreover, from the 2-D LDV measurements, the influence of channel slopes on the turbulent characteristics were fully investigated.

Abstract: Crude oils from different basins in China, Australia and New Zealand were analyzed to character ize aromatic hydrocarbons produced in different environments by means of GC/MS. The distributions of some common compounds such as naphthalene, phenanthrene, ehrysene, pyrene, fluoranthene, fluorene, dibenzothiophene and dibenzofuran were found to be related to sedimentary environments. Especially the relative contents of fluorenes, dibenzofurans and dibenzothiophenes can be used to divide the oils into three types: (1) saline or marine carbonate environment; (2 ) fresh-brackish water lake; (3) swamp and coal-bearing sequence. Aromatic biomarkers (e.g. retene, nor-abietene, derivatives of lupeol and β-amyrin) represent higher plant inputs with respect to the precursors of crude oils. High contents of sulphur-containing compounds like benzothiophene and dibenzothiophene series indicate a reducing sulphur-abundant diagenetic condition. The benzohopane series (C32–C35) was identified both in hypersaline and coal-bearing basins, and it is postulated to be the result of strong bacteria activity. In all the samples, a complete series of alkyl benzenes was analyzed. The similarity of its carbon-number distribution with that of n-alkanes probably suggests their genetic relationship. The distribution of the methylphenanthrene series reflects the evolution degree of crude oils, MPI holding a positive correlation with C29-sterane 20S/(20S+20R).

A fuzzy dark matter halo consists of a soliton core close to the center and a Navarro-Frenk-White-like density profile in the outer region. Previous investigations found that the soliton core exhibits temporal oscillations and random walk excursions around the halo center. Analyzing a set of numerical simulations, we show that both phenomena can be understood as the results of wave interference--a suitable superposition of the ground (solitonic) state and excited states in a fixed potential suffices to account for the main features of these phenomena. Such an eigenmode analysis can shed light on the evolution of a satellite halo undergoing tidal disruption. As the outer halo is stripped away, reducing the amplitudes of the excited states, the ground state evolves adiabatically. This suggests diminished soliton oscillations and random walk excursions, an effect to consider in deducing constraints from stellar heating. [ABSTRACT FROM AUTHOR]

The efficiency and safe range of LipofectamineTM2000 (LF2000)/bcl-xl applied in human keratocytes, the optimal ratio of LF2000/bcl-xl and the bcl-xl gene expression in human keratocytes were investiaged. By using trypan-blue staining, the effects of LF2000 and bcl-xl on the survival rate of the cultured human keratocytes were measured respectively. By using semi-quantitative RT-PCR, the efficiency and the expression of LF2000-mediated bcl-xl transfection into keratocytes were examined. The results showed that the survival rate of human keratocytes had no signficant change in the presence of LF2000 (20 μg/ml) or bcl-xl (10 μg/ml) for 24 h. LF2000 could effectively mediate the transfection of exogenous gene bcl-x1 into human keratocytes. The best transfection efficiency could be obtained when the ratio of bcl-xl/LF2000 was 1∶8. One day after transfection, the positive cells for bcl-x1 could be detectable, and the positive rate reached the peak on the post-transfection day 3 (48.3%), then gradually decreased. Fifteen days after transfection, there were few positive cells. It was suggested that LF2000 could effectively transfer the exogenous gene bcl-xl into human keratocytes without obvious toxicity during a concentration range. LF2000/bcl-xl may be likely to play an important role in gene therapy of human keratocytes.

With the improvement of computer performance and the gradual maturity of the computational methods, numerical wind tunnel in the simulation based on computational fluid dynamics has been developed rapidly and turned into one of the hottest investigated topics in computational wind engineering. Simulation method of turbulence, inflow turbulence generator method and the size of the grid scale are mainly included in the influence factors of the wind-induced response around the building in the computational domain. The above influence was analysed and summarized. The results show that the numerical wind tunnel in the simulation has made some good progress, but there are still a lot of contents that need to be further studied.

We investigate nonlinear structure formation in the fuzzy dark matter (FDM) model using both numerical and perturbative techniques. On the numerical side, we examine the virtues and limitations of a Schrödinger-Poisson solver (wave formulation) versus a fluid dynamics solver (Madelung formulation). On the perturbative side, we carry out a computation of the one-loop mass power spectrum, i.e. up to third order in perturbation theory. We find that (1) in many situations, the fluid dynamics solver is capable of producing the expected interference patterns, but it fails in situations where destructive interference causes the density to vanish--a generic occurrence in the nonlinear regime. (2) The Schrödinger-Poisson solver works well in all test cases, but it is demanding in resolution: suppose one is interested in the mass power spectrum on large scales, it is not sufficient to resolve structure on those same scales; one must resolve the relevant de Broglie scale which is often smaller. The fluid formulation does not suffer from this issue. (3) We compare the one-loop mass power spectrum from perturbation theory against the mass power spectrum from the Schrödinger-Poisson solver, and find good agreement in the mildly nonlinear regime. We contrast fluid perturbation theory with wave perturbation theory; the latter has a more limited range of validity. (4) As an application, we compare the Lyman-alpha forest flux power spectrum obtained from the Schrödinger-Poisson solver versus one from an N-body simulation (the latter is often used as an approximate method to make predictions for FDM). At redshift 5, the two, starting from the same initial condition, agree to better than 10% on observationally relevant scales as long as the FDM mass exceeds 2×10-23 eV. We emphasize that the so called quantum pressure is capable of both enhancing and suppressing fluctuations in the nonlinear regime--which dominates depends on the scale and quantity of interest. [ABSTRACT FROM AUTHOR]