Miracle-dz/UniFAR-FTUs huggingface dataset:
Total electron and proton energy input during auroral substorms: Remote sensing with IMAGE-FUV

[1] The IMAGE satellite carries three FUV imagers observing N2 LBH, O I 1356 A, and HI Lyman α emissions in the polar aurora. These simultaneous observations are used to characterize the precipitating electron and proton energy fluxes. The proton energy flux is derived from the Lyman α measurements on the basis of efficiency curves calculated with a Monte Carlo simulation of the proton aurora. The resulting proton contribution to the N2 LBH and O I 1356 A emissions is calculated and subtracted to obtain the electron contribution in the other two channels. These two quantities are used to determine the precipitating electron average energy and energy flux. The proton and electron energy fluxes are integrated over the hemisphere to obtain the rate of auroral energy dissipation (hemispheric power) carried by the protons and electrons separately. The time development of the proton and electron aurora during four winter time events is examined. Although the onsets of the proton and electron aurora coincide in time and space, the time of the peak of energy dissipation and the recovery time are often found to differ. The fractional energy flux carried by the protons is highest during quiet periods and reaches a minimum during the most active phase of the substorms. This result is in agreement with the dependence of the fractional proton hemispheric power on magnetic activity measured by NOAA 15. The hemispheric power deduced from the FUV images is compared to the NOAA-deduced values and found to be in reasonable agreement. Sources of uncertainties in the determination of the hemispheric power are discussed on the basis of several sensitivity tests. In particular, it is found that the most critical factor is the assumption made on the energy of the auroral protons if this energy is <25 keV.
Far-infrared observations of NGC 4945 and the Circinus galaxy

Results of observations of NGC 4945 and the Circinus galaxy carried out with a 1 m balloon-borne far-infrared telescope are reported. While only an upper limit (5 σ) of 150 Jy for the 150 μm flux density is obtained for Circinus, the central region of NGC 4945 has been mapped in two bands with effective wavelengths of ∼58 and ∼150 μm. Pointed observations of IRAS, using survey detectors, have been deconvolved to get higher angular resolution intensity maps at 12, 25, 60, and 100 μm, respectively, for both of these galaxies
Single‐microphone method for certain applications of the sound intensity technique

Recent developments of the two‐microphone intensity technique offer the possibility of improving measurements of acoustic impedance in impedance tube, sound transmission loss, and sound absorption coefficient in reverberation room. In these applications, the cross spectrum Gρ1ρ1 of the two microphone signals taken simultaneously is required. However, with the application of a deterministic source signal such as the periodic pseudorandom sequence [W. T. Chu, J. Acoust. Soc. Am. 76, 475–478 (1984)], Gρ1ρ2 can be obtained using a single microphone to measure the pressure at the two locations sequentially. Some of the inherent difficulties associated with the two microphone method are thus eliminated. The proposed method and some of the preliminary results will be presented.
Electron-impact ionization of the helium metastable 2 3S state

By performing multi-core electron–helium Born calculations we present a systematic study of the high-energy behaviour of the 2 3S total single ionization cross section which takes into account autoionization and ionization with excitation processes. We found that our results are in substantial disagreement with the previously reported Bethe–Born results of Briggs and Kim (1971 Phys. Rev. A 3 1342–9). We have also performed new close-coupling calculations within the frozen-core model and used them together with the multi-core Born calculations to establish theoretical estimates over the entire energy range of interest. At low energies the cross sections are only marginally higher than the other recently reported theoretical results, and therefore still substantially below the experimental data of Dixon et al (1976 J. Phys. B: At. Mol. Phys. 9 2617–31). At high energies we find that the multi-core calculations lead to significantly higher cross sections than the corresponding frozen-core calculations. However, as at the lower energies, experiment still remains substantially above the latest theory.
The Atlantic Climate Change Program

The Atlantic Climate Change Program (ACCP) is a component of NOAA's Climate and Global Change Program. ACCP is directed at determining the role of the thermohaline circulation of the Atlantic Ocean on global atmospheric climate. Efforts and progress in four ACCP elements are described. Advances include (1) descriptions of decadal and longer-term variability in the coupled ocean-atmosphere-ice system of the North Atlantic; (2) development of tools needed to perform long-term model runs of coupled simulations of North Atlantic air-sea interaction; (3) definition of mean and time-dependent characteristics of the thermohaline circulation; and (4) development of monitoring strategies for various elements of the thermohaline circulation. 20 refs., 4 figs., 1 tab.
NMR Chemical Shifts in Hard Carbon Nitride Compounds

We show that NMR chemical shift spectroscopy could help to identify the crystalline phases of hard carbon nitride compounds. To this purpose we compute the NMR chemical shifts of defect zinc-blende, cubic, {alpha}{minus} , {beta}{minus} , and graphitic C{sub 3}N{sub 4} with a newly developed {ital ab initio} method. The C shifts can be used to identify the CN bonds and to characterize C hybridization. The N shifts distinguish the {alpha}-C{sub 3}N{sub 4} from the {beta}-C{sub 3}N{sub 4} phases, and indicate the presence of the graphitic phase. {copyright} {ital 1998} {ital The American Physical Society}
Determination of optimal nudging coefficients

A four-dimensional variational assimilation (4D-Var) scheme is now widely used by meteorologicalcentres in a operational way. However, most of these applications do not take account of model error.Indeed, the classical 4D-Var with imperfect model formulation is unaffordable for current computationalmeans. This paper presents a low-cost method for dealing with model errors in 4D variationalassimilation. This method can be formally compared to a Kalman filter. This new scheme is tested ontwo configurations: first on a Burger equation, which allows one to calibrate the method, and secondon a more relevant shallow-water equations model, both in a twin experiment framework. It is shownthat, compared to classical 4D-Var results, this method provides a noticeable improvement.
On-Line Temperature Measurement Inside a Thermal Barrier Sensor Coating During Engine Operation

Existing thermal barrier coatings (TBCs) can be adapted enhancing their functionalities such that they not only protect critical components from hot gases but also can sense their own material temperature or other physical properties. The self-sensing capability is introduced by embedding optically active rare earth ions into the thermal barrier ceramic. When illuminated by light, the material starts to phosphoresce and the phosphorescence can provide in situ information on temperature, phase changes, corrosion, or erosion of the coating subject to the coating design. The integration of an on-line temperature detection system enables the full potential of TBCs to be realized due to improved accuracy in temperature measurement and early warning of degradation. This in turn will increase fuel efficiency and will reduce CO2 emissions. This paper reviews the previous implementation of such a measurement system into a Rolls-Royce jet engine using dysprosium doped yttrium-stabilized-zirconia (YSZ) as a single layer and a dual layer sensor coating material. The temperature measurements were carried out on cooled and uncooled components on a combustion chamber liner and on nozzle guide vanes (NGVs), respectively. The paper investigates the interpretation of those results looking at coating thickness effects and temperature gradients across the TBC. For the study, a specialized cyclic thermal gradient burner test rig was operated and instrumented using equivalent instrumentation to that used for the engine test. This unique rig enables the controlled heating of the coatings at different temperature regimes. A long-wavelength pyrometer was employed detecting the surface temperature of the coating in combination with the phosphorescence detector. A correction was applied to compensate for changes in emissivity using two methods. A thermocouple was used continuously measuring the substrate temperature of the sample. Typical gradients across the coating are less than 1 K/μm. As the excitation laser penetrates the coating, it generates phosphorescence from several locations throughout the coating and hence provides an integrated signal. The study successfully proved that the temperature indication from the phosphorescence coating remains between the surface and substrate temperature for all operating conditions. This demonstrates the possibility to measure inside the coating closer to the bond coat. The knowledge of the bond coat temperature is relevant to the growth of the thermally grown oxide (TGO) which is linked to the delamination of the coating and hence determines its life. Further, the data are related to a one-dimensional phosphorescence model determining the penetration depth of the laser and the emission.
Band bending mechanism for field emission in wide-band gap semiconductors

A theoretical model based on the band bending theory was developed for explaining the field-emission mechanism of wide-band gap semiconductors (WBGSs). It was shown that the maximum value of the band bending, which is nearly linearly proportional to the band gap of WBGSs, may amount to a few eV. Furthermore, the calculated field-emission energy distribution combined with the band bending analyzed on cubic boron nitride (c-BN) as typical one of WBGSs, indicated that the electron emission originates from the conduction band minimum resulting from the band bending. These results present a perspective to explain the field-emission mechanism, in which it is considered that the band bending, as well as the negative electron affinity, is of equal importance to the excellent field emission performances of WBGSs.
A Improved Infrared and Visible Images Matching Based on SURF

Images matching is the basis of image registration. For their difference, a improved SURF(speeded up robust features) algorithm was proposed for the infrared and visible images matching. Firstly, edges were extracted from the images to improve the similarity of infrared and visible images. Then SURF algorithm was used to detect interest points, and the dimension of the point descriptor was 64. Finally, found the matching points by Euclidean distance. Experimental results show that some invalid data points were eliminated.
Optimization Techniques For Edge And Contour Detection

This paper presents two new approaches for optimum detection of edges and contours in a gray level image of a scene with a constant background. The first algorithm determines the optimum tolerance for edge tracking that maximizes the number of edge pixels in each object in the image, while the second algorithm utilizes an iterative thresholding scheme in conjunction with a golden-section optimization technique to determine the optimum threshold that maximizes the number of contours and the number of pixels in the contours.
A comparison of low‐frequency radio noise amplitude probability distribution models

One of the most commonly modeled statistics in atmospheric radio noise studies is the noise envelope voltage amplitude probability distribution (APD). Although a number of models have been introduced to characterize atmospheric noise envelope APDs, the quantity of real data that exist to verify their accuracy is somewhat limited, especially in the ELF and VLF bands. This paper presents the results of a statistical analysis in which thousands of hours of ELF/VLF noise are processed to derive APDs, which are then compared with various APD models to determine which of the models is most accurate. The error criterion used to find the optimal parameters of each APD model, as well as to compare the models against each other, is the expected value of the log error squared (where the log error is the difference in decibels between the data histogram and the model histogram). This criterion provides a means by which the models may be evaluated and compared numerically. The most accurate model is found to depend on geographic location, time of year and day, bandwidth, and center frequency, but two of the simplest models (i.e., each with only two parameters) are found to give extremely good performance in general. These are the Hall and alpha‐stable (or α‐stable) models, both of which approximate the Rayleigh distribution for low‐amplitude values but decay with an inverse power law for high‐amplitude values. This paper concludes that the Hall model is the optimal choice in terms of accuracy and simplicity for locations exposed to heavy sferic activity (e.g., lower latitudes) and the α‐stable model is best for locations relatively distant from heavy sferic activity (e.g., the polar regions).
Advanced self-aligned double patterning development for sub-30-nm DRAM manufacturing

Although the Numerical Aperture (NA) has been greatly improved from 0.93 (dry) to 1.35 (wet) by the introduction of modern water immersion 193nm scanner since 2001, the realistic single exposure photolithography printing for mass production is still limited to ~40nm, even with the help of a variety of Resolution Enhancement Techniques (RETs). Theoretically, the 193nm immersion scanner with high index fluid or Extreme UV (EUV) scanner with a significantly shorter wavelength of 13.5nm would be the logical successors to water immersion 193nm scanner. However, considering tremendous technical difficulties to work with high index fluids and relatively immature and very low productivity of EUV at the moment, it's likely that both candidates have little chance to entering production prior to 2012. Additionally, the production schedule can be further pushed out due to formidable initial investment for the costly equipment and consumables associated with EUV given the present worldwide economic recession. Nano-imprint may be attractive for its low cost and versatile nature, however, long-term stability and logistics under production stress yet to be established. The hope to continue the thrust of Moore's Law into the sub-40nm regime before EUV era heavily counts on the success of the so-called Double Patterning Techniques (DPT). A variety of integration schemes have been developed or are still under development to harness the full capacity of DPT. Among them the spacer double patterning approach stands out because of the self-aligned characteristics and a cumulative great deal of experience on the handling of the spacer-related processes in traditional CMOS process integration. The final goal of most research works around Self-Aligned Double Patterning (SADP) focuses on achieving minimal added cost and high quality printing at the same time. However, most of the time the quality and the cost are compromised by applying non-production proven new material/new hardware and/or fancy integration approaches. In our study we purposely apply a more "classical" and relatively conservative integration scheme, with all unit process steps long proven in previous volume production. By carefully optimizing the relative CMP, films deposition, etch and cleaning processes, we are able to demonstrate 30nm line/space patterns by an NA 0.93 dry 193nm scanner with optimal CDU better than 3nm and high frequency line edge roughness (LER) close to 2nm/side. Additionally, by analyzing wafer quality for alignment and alignment residual in various alignment & overlay mark designs, projected residual overlay as little as 4nm can be readily obtained.
Developments in laser processing for silica-based planar lightwave circuits

Laser processing offers an attractive way of manufacturing both optical and biomedical devices including microfluidic channels and biochips. Laser processing is also promising for the fabrication and trimming of silica-based planar lightwave circuits (PLCs). PLCs are key functional components for use in optical telecommunication systems since they offer compactness and high functionality in addition to excellent stability. A laser light that strongly interacts with glass, such as ultraviolet (UV) light or femtosecond pulses, can increase the refractive index of glass. This phenomenon can be used to improve the performance of PLCs as well as to enhance their functionality. UV laser trimming is useful in that it can be used to change the refractive index of fabricated waveguides and thus compensate for fabrication errors. Fabrication errors have various detrimental effects on PLC performance including deviation from the designed wavelength, polarization dependence and crosstalk degradation. UV laser trimming can greatly improve PLC performance by compensating for these errors. In addition, laser processing can provide PLCs with new functionalities. For example, a UV laser can be used to produce band-reflection mirrors in external cavity lasers in PLCs. Direct waveguide writing is also an attractive way to enhance circuit layout flexibility. Recently, a femtosecond laser was found to be effective for writing 3-dimensional waveguides, and it can also be used to interconnect waveguides flexibly. This enables us to expand PLC geometry from two to three dimensions. This talk will review trends in laser processing for PLC fabrication and recent R and D topics.
Stochastic Kolmogorov-Type Population Dynamics with Variable Delay

In general, population systems are often subject to environmental noise. To examine whether the presence of such noise affects population systems significantly, we stochastically perturb the delay Kolmogorov-type system = diag(x 1(t),…, x n (t))f(x(t), x(t − δ(t))) into the stochastic delay differential equation dx(t) = diag(x 1(t),…, x n (t))[f(x(t), x(t − δ(t)))dt + g(x(t), x(t − δ(t)))dw(t)]. Under the traditional diagonal dominance condition, we study the existence and uniqueness of the global positive solution of this stochastic system, and its asymptotic-bound properties. These properties are natural requirements from the biological point of view. As the special cases, we also discuss some stochastic Lotka–Volterra systems.
A General Theory of X-ray Intensity Statistics for Twins by Merohedry

A general theory of X-ray intensity statistics for twins by merohedry is developed based on mathematical analogy of this problem to a one-dimensional random walk. Probability distribution functions are derived (a) for intensities from a single twinned specimen, and (b) for the differences in intensities from two separate twinned specimens. Theoretical values of a discrepancy index between observed intensities from a twin, and calculated intensities from both correct and incorrect structural models are evaluated. A new method for determining volume fractions of crystals in a twin is also proposed, based on the distribution of differences in intensities between twin-related reflections. These results have implications for the treatment of isomorphous replacement data collected from twins by hemihedry.
Spectral dyadic Green's function formulation for planar integrated structures

The problem of the complete determination of the dyadic spectral Green's function for an integrated planar structure with a grounded dielectric slab has been considered and solved in a rigorous way by using the spectral theory of the electromagnetic field. The reciprocity theorem and the geometrical symmetry of the structure have demonstrated the different roles played by the independent terms of the spectral Green's function in the evaluation of the electromagnetic characteristics of the grounded slab excited with a general source. Furthermore, an equivalent circuit representation of the structure, allowing a noteworthy simplification in the determination of the total power, has been obtained. These equivalent circuits and the derived spectral Green's function presented here can be used to analyze and design microstrip antennas of arbitrary shape with a general type of loading, such as matched or unmatched loads, parasitic, and shorting pins. >
Measurement of acoustic impedance using a capillary: An attempt to achieve optimization

The choice of the dimensions of capillary tubes used for acoustic impedance measurements (with applications to wind musical instruments or materials) depends on the frequency and impedance ranges. It is shown that there is an optimum range for the ratio of the length of the tube to its area, in order to have a flat amplitude response over a wide range of frequency. Several shapes of capillaries, in particular a narrow slit with arbitrary shape, such as a hexagon inscribed in a circle, using an approximate theory of viscothermal effect are studied. The upper limit of frequency does not depend on the shape, but only on the length of the capillary. Therefore, the choice of the dimensions starts with the frequency range, and our study allows one to deduce successively the length, the transverse dimension related to the width of the slit, and finally, from the impedance range, the transverse dimension related to the number of capillaries.
Analysis of cavitating flow structure by experimental and numerical investigations

The unsteady structure of cavitating flows is investigated by coupled experimental and numerical means. Experiments focus on the structure and dynamics of sheet cavitation on the upper side of a two-dimensional foil section in the ENSTA cavitation tunnel. Various flow conditions are investigated by varying the pressure, the flow velocity, and the incidence of the foil section. High-frequency local measurements of volume fractions of the vapour phase are performed inside the liquid/vapour mixture by a X-ray absorption method. The numerical approach is based on a macroscopic formulation of the balance equations for a two-phase flow. The assumptions required by this formulation are detailed and they are shown to be common to almost all the models used to simulate cavitating flows. In the present case we apply a single-fluid model associated with a barotropic state law that governs the mixture density evolution. Numerical simulations are performed at the experimental conditions and the results are compared to the experimental data. A reliable agreement is obtained for the internal structure of the cavity for incidence varying between 3° and 6°. Special attention is paid to the mechanisms of partial and transitional instabilities, and to the effects of the interaction between the two sides of the foil section.