K-band cross section

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Temperature dependent ozone absorption cross section spectra measured with the GOME-2 FM3 spectrometer and first application in satellite retrievals

Temperature dependent ozone absorption cross section spectra measured with the GOME-2 FM3 spectrometer and first application in satellite retrievals

Abstract. The Global Ozone Monitoring Experiment-2 (GOME-2) Flight Model (FM) absorption cross section spec- tra of ozone were measured under representative atmospheric conditions in the laboratory setup at temperatures between 203 K and 293 K in the wavelength range of 230–790 nm at a medium spectral resolution of 0.24 to 0.54 nm. Since the exact ozone amounts were unknown in the gas flow system used, the measured ozone cross sections were required to be scaled to absolute cross section units using published liter- ature data. The Hartley, Huggins and Chappuis bands were recorded simultaneously and their temperature dependence is in good agreement with previous studies (strong tempera- ture effect in the Huggins band and weak in the Hartley and Chappuis bands). The overall agreement of the GOME-2 FM cross sections with the literature data is well within 3 %. The total ozone column retrieved from the GOME-2/MetOp-A satellite using the new cross section data is within 1 % com- pared to the ozone amounts retrieved from the standard re- trieval performed for GOME-2.
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Radar micro Doppler signatures of drones and birds at K band and W band

Radar micro Doppler signatures of drones and birds at K band and W band

Along with presenting bird micro-Doppler results at K-band and W-band simultaneously for the first time, this paper also reports on the experimental results of drone micro-Doppler at the same two frequency bands. For a low power system like that we have used during data collection (transmit power about 200 mW and antenna gain of about 33 dBi), the K-band radar will have a range coverage for a typical drone or bird (RCS approxi- mately − 20 dBsm) with a 10 dB SNR of about 700 m, for a single shot measurement. In contrast, a W-band radar with similar parameters will have a range coverage of about 380 m. Even though higher frequency radars may have reduced range coverage, they offer other attributes which are advantageous from an end-user’s perspective. Hence, W-band might be chosen as it will require a small antenna, thus yielding a very compact system. On the other hand, a K-band system may be a very good trade-off between longer ranges at the expense of a physically larger system whilst leveraging low cost radar chipsets. To investigate thoroughly the micro-Doppler characteris- tics at these frequency bands, different types of drones and birds have been used. The results shown in this paper clearly demonstrate the characteristic micro-Doppler properties of drones and birds separately, at K-band and W-band, as well as how the properties compare and contrast with respect to each other. It should be noted that whilst the data also contain information on the absolute radar cross section (RCS) of the targets, as all the radars were very well calibrated, the detailed analysis of their RCS is reported in a separate publication 19 . This paper
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Speech Enhancement Using Cross Correlation Compensated Multi Band Wiener Filter Combined with Harmonic Regeneration

Speech Enhancement Using Cross Correlation Compensated Multi Band Wiener Filter Combined with Harmonic Regeneration

The output signal S k ˆ i   or s t ˆ   in time domain, ob- tained by the multiband Wiener filter presented in the previous section still suffers from distortions. This is inherent to the estimation errors introduced by the noise spectrum estimation since it is very difficult to get reliable instantaneous estimates in single channel noise reduction techniques. Since 80% of the pronounced sounds are voiced in average, the distortions generally turnout to be harmonic distortion. Indeed, some harmonics are consid- ered as noise only components and are suppressed. For that reason, we propose to process the distorted signal to create a fully harmonic signal where all the missing har- monics are regenerated. This signal will then be used to compute a spectral gain able to preserve the speech har- monics. This will be called the speech harmonic regen- eration step and can be used to improve the results of any noise reduction technique and not only the multiband Wiener filter.
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Fast and Accurate Radar Cross Section Computation Using Chebyshev Approximation in Both Broad Frequency Band and Angular Domains Simultaneously

Fast and Accurate Radar Cross Section Computation Using Chebyshev Approximation in Both Broad Frequency Band and Angular Domains Simultaneously

The RCS is a function of both frequency and incident angle. The RCS contains both frequency and angle information simultaneously. In many practical applications, it is desirable to predict the three- dimensional RCS pattern of an arbitrary shaped object in both a frequency band and angular domains simultaneously. In [15], a simultaneous extrapolation technique based on AWE technique is proposed to predict RCS in both angular and frequency domains. However, this method trades reduced CPU time for increased memory. The expected effect frequency band is limited by the inherent property of the Taylor series, and the memory needed is greatly increased on account of the high-order derivatives of the dense impedance matrix and excitation matrix with respect to k and θ simultaneously.
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Stress in V section band clamps

Stress in V section band clamps

V-band clamps are also frequently employed within the aerospace industry to fasten satellites to the delivery vehicle during launch and ascent. In this exacting environment, the importance of the satellite–launch vehicle interface on the dynamic behaviour of the satellite has been recognized by Stavrinidis et al. { 3}. Lin and Cole { 4}also identiŽ ed the stiffness of the clamp as a key variable in their dynamic analysis and stated that stiffness values presented by the manufacturers were inaccurate. The difŽ culty of using clamps of this type has been recognized by NASA { 5}who recommend that when clamps are installed, they are loaded incrementally and tapped around the periphery to help produce a uniform internal circumferential force. It is also recommended that this force be monitored using a number of strain gauges. In order to avoid this complicated and time-consuming procedure, Lancho et al. { 6}have proposed a clamp system using a much stiffer band than normal, which is effectively shrunk on to the interface  anges.
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Plastic deformation in flat section band clamps

Plastic deformation in flat section band clamps

Flat band clamps are widely used for connecting flexible tubes or hoses to comparatively rigid ducts or pipes. They consist of a simple circular band of material carrying two trunnion straps, as shown in Fig. 1. The band is tightened using a T-bolt connecting the two trunnions. The purpose of the flat-section band clamp is to provide a pressure seal between the components by supplying the required radial pressure on the flexible component of the joint. Band clamps have been available for many years, and developments to try to ensure that the radial load is evenly distributed have taken place over a similar period. These include overlap- ping the ends of the band, as suggested by Jones [1], and including inserts in the area under the T-bolt, as advocated by Schaub [2]. Recently, Shoghi et al. [3] have described the elastic behaviour of such clamps and demonstrated that, owing to frictional effects, it is unlikely that the radial load will be evenly distributed.
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Afipia clevelandensis antibodies and cross-reactivity with Brucella spp. and Yersinia enterocolitica O:9.

Afipia clevelandensis antibodies and cross-reactivity with Brucella spp. and Yersinia enterocolitica O:9.

Afipia clevelandensis is a recently described gram-negative bacterium whose potential pathogenic role in hu- man disease is under investigation. Only one strain, from the pretibial lesion of a patient hospitalized with necrotizing pancreatitis for 5 months, has been isolated. Using an indirect immunofluorescence assay to detect anti-A. clevelandensis antibodies, we found a seroprevalence of 1.5% among 30,194 sera routinely submitted for laboratory diagnosis of rickettsial diseases. However, among the 52 patients who were clinically evaluable and who exhibited detectable antibodies against A. clevelandensis, 42% were eventually diagnosed as certainly or probably having brucellosis and 15% were eventually diagnosed as certainly or probably having Yersinia enterocolitica O:9 infection, which is the serotype most often encountered in Europe. Western immunoblotting and cross-adsorption tests showed that an 11.5-kDa proteinase K-labile band and a 21-kDa proteinase-stable band, presumably lipopolysaccharide, were responsible for cross-reactivity among A. clevelandensis, Brucella abortus, and Y. enterocolitica O:9. Other diagnoses included nosocomial infections and various community- acquired diseases for which the role of A. clevelandensis remains undefined. Physicians and clinical microbi- ologists should be aware of this cross-reactivity in future assessments of the role of A. clevelandensis in human pathology.
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Corm damage caused by banana weevils Cosmopolites sordidus (Germar) collected from different banana growing regions in Uganda

Corm damage caused by banana weevils Cosmopolites sordidus (Germar) collected from different banana growing regions in Uganda

Background: In this study, both healthy tissue culture plantlets and maiden suckers of the Nakitembe cultivar were used to assess the damage level variation caused by banana weevils collected from different banana growing regions. Seventy-nine (79) tissue culture plantlets and fifty (50) suckers were established in buckets in a randomized complete block design for 5 months. Ten adult weevils (5 females and 5 males) were introduced at the base of each plant, and the buckets were covered with a weevil proof mesh. Weevil damage was estimated as a percentage at 60 days after the weevil introduction by estimating the peripheral damage (PD), total cross section corm damage (XT) and above the collar damage (ACD).
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Origins of improved carrier multiplication efficiency in elongated semiconductor nanostructures

Origins of improved carrier multiplication efficiency in elongated semiconductor nanostructures

Nanorod solar cells have been attracting a lot of attention recently, as they have been shown to exhibit a lower carrier multi- plication onset and a higher quantum efficiency than quantum dots with similar bandgaps. The underpinning theory for this phenomenon is not yet completely understood, and is still the subject of ongoing study. Here we conduct a theoretical investiga- tion into CM efficiency in elongated semiconductor nanostructures with square cross section made of different materials (GaAs, GaSb, InAs, InP, InSb, CdSe, Ge, Si and PbSe), using a single-band effective mass model. Following Luo, Franceschetti and Zunger we adopt the CM figure of merit (the ratio between biexciton and single-exciton density of states) as a measure of CM efficiency and investigate its dependence on the aspect ratio for both (a) constant cross section (i.e. varying the volume) and (b) constant volume (i.e., varying the cross section), by decoupling electronic structure effects from surface-related effects, increased absorption and Coulomb coupling effects. The results show that in both (a) and (b) cases elongation causes an increase in both single- and bi-exciton density of states, with the latter, however, growing much faster with increasing energy. This leads to the availability of more bi-exciton states than single-exciton states for photon energies just above the bi-exciton ground state and therefore suggests a higher probability of CM at these energies for elongated structures. Our results therefore show that the ori- gin of the observed decrease of the CM threshold in elongated structures can be attributed purely to electronic structure effects, paving the way to the implementation of CM-efficiency-boosting strategies in nanostructures based on the lowering of the CM onset.
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Numerical Study of Non-Newtonian Flow Through Rectangular Microchannels

Numerical Study of Non-Newtonian Flow Through Rectangular Microchannels

increases and the wall shear stress, and consequently the friction factor, increases. For a given power law index and channel aspect ratio, an increase in the slip coefficient leads to a decrease in the product of the friction factor and the Reynolds number. This decrease in f  Re is caused by lower wall velocity gradients due to higher slip coefficients. The results of Fig. 7 and Table 6 emphasize the importance of the aspect ratio. Indeed, narrowing the cross section by increasing the aspect ratio enhances f.Re because of the resulting higher velocity gradient close to the walls.
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Reanalysis of rate data for the reaction CH3 + CH3 → C2H6 using revised cross sections and a linearized second-order master equation

Reanalysis of rate data for the reaction CH3 + CH3 → C2H6 using revised cross sections and a linearized second-order master equation

corrected CASPT2/cc-pvdz potential energy surface. They applied a 15% reduction in the rate coefficient to correct for local re-crossings of the transition state dividing surface, deduced from dynamical calculations. They obtained = 1.57 × 10 -9 T -0.538 exp(-68 K/T). As shown in Fig. 6, this expression shows a steeper temperature dependence than obtained from Model I, but is comparable to the results from Model II. The agreement is good at 300 K and differs at 2000 K by 27% for Fit 5 and only 4% for Fit 6; the difference for the mean value expression quoted above is 16%. This is very satisfactory agreement given the long extrapolation in p and T involved. Fig. 6 also shows the calculated results obtained by Klippenstein and Harding 11 in an earlier analysis based on an MRCI potential, without a dynamical correction. A further plot is shown of the data of Zheng et al. 61 who used density functional theory (M06-L), obtaining a stronger negative T dependence. Fig. 6 also shows the results from Hessler and Ogren, 15 based on fitting experimental data to a number of analytic representations of k(p,T). They recommended = 8.78 × 10 -11 exp(-T/723 K), which shows a stronger negative temperature dependence than the present analysis. In a later paper, Hessler 63 showed that the data are compatible with a range of T dependences, including one close to that found here, depending on the fitting method used.
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The SCUBA-2 Cosmology Legacy Survey: the clustering of submillimetre galaxies in the UKIDSS UDS field

The SCUBA-2 Cosmology Legacy Survey: the clustering of submillimetre galaxies in the UKIDSS UDS field

flux density for the SMG sample at redshifts 1 < z < 3. We found no significant trend, however, since the uncertainties were too large. Finally, it is worth noting that clustering measurements per- formed with single-dish surveys are subjected to a blending bias (e.g. Hodge et al. 2013; Karim et al. 2013; Cowley et al. 2016). This describes the contribution to the clustering signal due to the blending of SMGs into single submillimetre sources as a result of the low resolution. We discuss this in detail in Section 4.3. Summa- rizing briefly, Cowley et al. (2016) simulated this effect at 850 µ m to match observations in the SCUBA-2 map. They suggest that the confusion between the sources can artificially increase the galaxy bias measurements by a factor of ∼ 2 and that any galaxy bias mea- sured with a single-dish survey must be corrected for by this factor. We note that the factor ∼ 4 derived in Cowley et al. (2016) ap- plies to the clustering amplitude, A, for which this quantity scales with the galaxy bias squared b 2 . In addition, surveys with larger
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An upper bound on the total inelastic cross section as a function of the total cross section

An upper bound on the total inelastic cross section as a function of the total cross section

The Froissart-Martin bound has been seminal both to the development of the field of high energy theorems in axiomatic field theory (see e.g. the review [6])and to that of phenomenological models leading to accurate predic- tions of total and elastic cross sections before their ex- perimental measurem ents [7]. Remarkably, one of us (A. M.) has recently obtained a bound on the total inelastic cross section at high energy [8],

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An Approach for Transmission Loss Validation and Measurement of Various Reactive Mufflers with FEA Acoustic Module

An Approach for Transmission Loss Validation and Measurement of Various Reactive Mufflers with FEA Acoustic Module

A muffler is an important noise control element for reduction of machinery exhaust noise, fan noise and other noise sources involving flow of a gas. Basically, muffler is designed for two reasons: 1) High noise attenuation performance, a basic necessity of a muffler. 2) Minimum back pressure, it represents the extra static pressure acted by the muffler on the engine. Mufflers are of two types: the reactive type and absorptive type. Reactive mufflers work on the principle of impedance mismatch by use of sudden changes in the area of cross-section, perforated elements, resonators etc.
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Planning and Analysis of Irrigation Tunnel

Planning and Analysis of Irrigation Tunnel

The tunnel is laid in rock surface is about 10Kms. The width of the tunnel is 6.5m and the height of the tunnel is 7.15m. The sequence of the project that we followed are estimation of water quantity discharge, arrival of cross section, analysis of cross section, design of cross section, rate analysis of tunnel cross section. The drawing plan is done using AutoCAD software.

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Cross section distribution dynamics

Cross section distribution dynamics

The data are taken from OECD statistics, in particular the GDP (and its components) is drawn from National Accounts, 1960-1991 which uses the System of National Accounts (SNA) definitions. The sample covers 24 countries over a period of 31 years (1960-1990). Every nominal variable has been transformed in real terms by using its price index from National Accounts, then expressed in national dollars of 1985 by using estimated PPPs from 1990 for each aggregate. PPPs series are calculated involving only OECD countries10. The basic variable of analysis is the per-capita GDP in each individual country relative to the same variable for the entire OECD as a whole11. Figure 3 is a three dimensional plot of the variable, for the 24 economies over the 31 years of the sample. It is clear that both dimensions of variation in the data appear to be very important and the regression analysis is missing a significant amount of the dynamics. It is precisely this two dimensional dynamics that we are interested in, for which conventional convergence analysis is not well suited. For example, the cross-section analysis simply takes the slope of the linear time trend for each country over the time sample and studies the dynamics of that slope across economies. In this way most of the time dimension is lost Alternatively estimating (2.3) for each individual country the cross-section dynamics is lost.
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FT IR Microspectroscopic Imaging of Cross Sectioned Human Hair during a Bleaching Process

FT IR Microspectroscopic Imaging of Cross Sectioned Human Hair during a Bleaching Process

terfacing with the cuticle in the hair bleached for 30 min. The areas having strong ab- sorbance for cysteine monoxide are spread throughout the cortex. Presumably, the hy- drogen peroxide that had permeated from the cuticle penetrated the cortex region. Af- ter 90 min of bleaching, the absorbance band due tocystine monoxide can be seen to cover the entire cross-sectioned hair, indicating that the entire hair, from the cuticle to the cortex, was significantly attacked by hydrogen peroxide. Although this observation may not necessarily correlate with the actual color change upon bleaching, we can, nevertheless, conclude that 1) the cleavage and oxidation of disulfide bonds is complete within the first 90 minutes of hydrogen-peroxide treatment, and 2) the formation of cystine derivatives does not affect the protein’s tertiary structure (i.e., keratin’s helical structure) significantly.
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Article Compulsory Schooling and Returns to Education: A Re-Examination

Article Compulsory Schooling and Returns to Education: A Re-Examination

we change its prior stance to explicitly specify s as an imperfect indicator of the latent variable, ‘aptitude’. However, measurement error can provide 𝛽 in (3) with a plausible interpretation differently from that of 𝛽 . However, this interpretation would undermine the basic IV-based claim of 𝛽 being the consistent estimator of ARTE with respect to s, and openly recognise (1) and (3) as two different models, with (3) effectively yielding ARTA. As for selection bias, the argument extends to the situation where CSL treatment could alter the population composition of educated workers, as compared to that of the pre-treatment population, e.g., through a diluted concentration level of ‘aptitude’ (see Angrist and Pischke 2009, chp. 4). Consequently, the post-treatment schooling effect becomes significantly different from the pre-treatment one due to a change in level of ‘aptitude’ for different years of schooling post-treatment. Two problems hinder this argument. First, there lacks a credible way to verify that a compositional shift, if it has occurred, is adequately reflected by 𝑠 generated via (2). From the perspective of retrospective cross-section data, empirical assessment of the possibility of such a shift entails disaggregation. Specifically, we need to carefully divide the available samples into two parts—an L-treated part versus a CSL unaffected part—so as to investigate
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Effect of hydraulic coefficient on membrane performance for rejection of emerging contaminants

Effect of hydraulic coefficient on membrane performance for rejection of emerging contaminants

Figure 3 illustrates the cross-section images of PSf and mixed matrix membranes. EDAX study of the membrane was performed and it shows presence of Al, Si, and N in the membrane, which confirms the presence of PANi-HNT in the membrane matrix. Of particular interest, Fig. 3(b – d) exhibit mixed matrix membranes with the concentration of PANi-HNT increases from 0.25 to 1%, respectively. The cross-section reveals the presence of a dense layer, a fi nger like middle layer and a bottom supportive layer system. The fi nger like projections are narrow in PSf membrane, whereas increasing the concentration of PANi-HNT, this projection became broad while micro channels on the surface layer become thinner. In the bottom layer, however, the macrovoids are longer with the increase in the concentration of the PANi-HNT, below the finger like projections. There are two important parameters, effec- tively for such macrovoids during phase inversion are; i) hydrophilicity and ii) viscosity of the casting solution [28]. Hydrophilicity increases the intake of non-solvents (water) in the solvent/non-solvents exchange and higher the viscosity decreases the rate of solvent exchange which causes macrovoids [29]. In this case the PANi-HNT is hydrophilic in nature meanwhile metal oxides decrease the viscosity of the casting solution. Hence, macrovoids are larger with respect to higher con- centration of PANi-HNT The hydrophilicity of the membranes also supports the above phenomenon, and was confirmed by water uptake and contact angle studies. In higher concentration, the water movement is irregular because of more hydrophilic interaction doing phase in- version. Hence, twisted finger like projections were observed in higher concentration of PANi-HNT membranes.
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Reading K 12 Section 35

Reading K 12 Section 35

*Competencies and skills incorporate the scientifically based reading research (SBRR) and the components of Florida's formula for reading success addressing improved reading outcomes f[r]

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