A study was made of the introduction rate of radiation defects ΔNdef/ΔD versus the fast electron irradiation dose (D) in semiconductor crystals of n-Si and n-GaP. We take the concentration of ...radiation defects concentration Ndef to be the difference between the carrier concentration of semiconductors before n0 and after irradiation n(D) at the dose D, delivered at room temperature. By application of an appropriate fitting function to the dose dependent curves of the Ndef(D), it was demonstrated that the empiric exponential law of the form Ndef=n0(1−exp(−D/D0)) gives the best agreement with the experimental data, irrespective of the electron energy and irradiation dose. D0 is the irradiation dose, at which the carrier concentration n(D) at a temperature T=300K decreases by a factor of e. The results showed that the formation of radiation defects in the samples studied is not a linear process and ΔNdef/ΔD are found to decrease exponentially with increasing irradiation dose, according to their particular character. Using the same fitting method, it was found that for certain samples, beyond a particular radiation dose level, the rate of carrier mobility versus radiation dose also decreased exponentially.
•Radiation defects' concentration can be shown as an exponential decreasing function.•Radiation defects are formed in silicon crystals by a non-linear process.•Introduction rate of radiation defects depends on nature of the defects themselves.•Generation rate of radiation defects depends on electrically non-active impurities.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Tapping pine sap is a sufficient job to help increase the income of the community around the forest. People are interested in working as tappers if the income earned can meet family needs and ...contribute better income than other jobs. The purpose of this study was to determine the pine sap tapping technique, as well as to find out how much income the tappers had and the factors affecting the income of pine sap tappers in Cenrana Baru Village, Cenrana District, Maros Regency. The sap tapping technique was analyzed using descriptive analysis, while the amount of income and the factors that influenced it were analyzed using descriptive quantitative data analysis. The results showed that the tapping technique used by pine sap tappers in Cenrana Baru Village, Cenrana District, was the koakan technique (quarre) with an average monthly income of IDR 2,523,661.27. The results of the regression analysis showed that the factors that had an effect on income were the tapping area, the production of pine sap and the wages of the pine sap. The tapping activity carried out by sap tappers in Cenrana Baru Village requires guidance from related parties so that these activities can be carried out properly with minimal damage to pine stands. As well as the company needs to consider and determine the determination of wages based on the distance from the tapping site to the sap collection point.
The design and operation of an experimental installation are described, used for simulating those factors that most greatly affect the properties of materials and microelectronic devices in ...conditions of the near Earth (Low Earth Orbit) environment. The simulator apparatus is in the form of a cylindrical metal vacuum chamber constructed and mounted to the electron accelerator facility of the Center for the Advancement of Natural Discoveries using Light Emission Synchrotron Research Institute (Armenia) which allows the production of accelerated electrons with the following parameters: ultra-short pulse duration (τ = 4·10−13 s), electron energy 3.5 MeV, pulse current intensity 60 A/cm2, pulse frequency 12 Hz. A comparison may be made with conventional electron accelerators, which employ micro-second pulse duration, and a far lower current intensity of 2∙10−3 A/cm2. Thus, the specific features of this installation enable the simulation of ultra-fast processes as occur in cosmic space or under other extreme conditions. Here, we present the initial results obtained, concerning the influence of high-density electron irradiation on the behavior of the electro-physical properties of silicon crystals. Peculiarities and differences are presented between the results obtained from silicon crystals irradiated by electrons with an energy of 3.5 MeV and a pulse duration of τ = 4·10−13 s, and those from silicon samples irradiated with 7.5 MeV or 50 MeV energy electrons, using conventional electron accelerators.
•A vacuum chamber was designed and constructed for LEO environment simulation.•The chamber was connected to ultra-short pulse duration electron beam.•The simulator tested and parameters correspond to the main LEO conditions.•First results are presented on silicon properties investigation in the simulator.•The created stand allows in-situ and complex study of materials under LEO factors.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
With a large sample of bright, low-redshift galaxies with optical–near-IR imaging from the GAMA survey we use bulge-disc decompositions to understand the wavelength-dependent behaviour of ...single-Sérsic structural measurements. We denote the variation in single-Sérsic index with wavelength as
$\mathcal {N}$
, likewise for effective radius we use
$\mathcal {R}$
. We find that most galaxies with a substantial disc, even those with no discernable bulge, display a high value of
$\mathcal {N}$
. The increase in Sérsic index to longer wavelengths is therefore intrinsic to discs, apparently resulting from radial variations in stellar population and/or dust reddening. Similarly, low values of
$\mathcal {R}$
(< 1) are found to be ubiquitous, implying an element of universality in galaxy colour gradients. We also study how bulge and disc colour distributions vary with galaxy type. We find that, rather than all bulges being red and all discs being blue in absolute terms, both components become redder for galaxies with redder total colours. We even observe that bulges in bluer galaxies are typically bluer than discs in red galaxies, and that bulges and discs are closer in colour for fainter galaxies. Trends in total colour are therefore not solely due to the colour or flux dominance of the bulge or disc.
Using single-component fits to SDSS/UKIDSS images of galaxies in the G09 region of the GAMA survey we study radial colour gradients across the galaxy population. We use the multi-wavelength ...information provided by MegaMorph analysis of galaxy light profiles to calculate intrinsic colour gradients, and divide into six subsamples split by overall Sérsic index (n) and galaxy colour. We find a bimodality in the colour gradients of high- and low-n galaxies in all wavebands which varies with overall galaxy luminosity. Global trends in colour gradients therefore result from combining the contrasting behaviour of a number of different galaxy populations. The ubiquity of strong negative colour gradients supports the picture of inside-out growth through gas accretion for blue, low-n galaxies, and through dry minor mergers for red, high-n galaxies. An exception is the blue high-n population which has properties indicative of dissipative major mergers.
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FMFMET, NUK, UL, UM, UPUK
Objective To compare synthetic oxytocin infusion regimens used during labour, calculate the International Units (IU) escalation rate and total amount of IU infused over eight hours. Design ...Observational study Setting Twelve countries, eleven European and South Africa. Sample National, regional or institutional-level regimens on oxytocin for induction and augmentation labour Methods Data on oxytocin IU dose, infusion fluid amount, start dose, escalation rate and maximum dose were collected. Values for each regimen were converted to IU in 1000ml diluent. One IU corresponded to 1.67mug for doses provided in grams/micrograms. IU hourly dose increase rates were based on escalation frequency. Cumulative doses and total IU amount infused were calculated by adding the dose administered for each previous hour. Main Outcome Measures Oxytocin IU dose infused Results Data were obtained on 21 regimens used in 12 countries. Details on the start dose, escalation interval, escalation rate and maximum dose infused were available from 16 regimens. Starting rates varied from 0.06 IU/hour to 0.90 IU/hour, and the maximum dose rate varied from 0.90 IU/hour to 3.60 IU/hour. The total amount of IU oxytocin infused, estimated over eight hours, ranged from 2.38 IU to 27.00 IU, a variation of 24.62 IU and an 11-fold difference. Conclusion Current variations in oxytocin regimens for induction and augmentation of labour are inexplicable. It is crucial that the appropriate minimum infusion regimen is administered because synthetic oxytocin is a potentially harmful medication with serious consequences for women and babies when inappropriately used. Estimating the total amount of oxytocin IU received by labouring women, alongside the institution's mode of birth and neonatal outcomes, may deepen our understanding and be the way forward to identifying the optimal infusion regimen.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The relevance of the study is associated with the need to develop and improve technological methods for increasing oil production from the Bazhenov Formation in relation to the depletion of reserves ...in traditional granular reservoirs in the West Siberian oil and gas province. The features of the industrial development of these low-permeability rocks largely depend on their mineral-component composition. To identify different types of reservoirs of the Bazhenov Formation in wells that are not characterized by core material, it is necessary to develop a method for predicting its lithological composition. The main aim: to identify and study the relationships between the mineral component composition, and electrical rocks and radioactive properties of Bazhenov Formation in the central part of the West Siberian sedimentary basin for developing methods of calculating the content of basic rock-forming components in this formation section. The object of the research is the carbonate-argillaceous-siliceous rocks of the Bazhenov Formation, characterized by a large heterogeneity of the mineral-component composition along the section. Methods: identification of relationships between the mineral-component composition of the rocks of the Bazhenov Formation and its electrical and radioactive properties; statistical analysis of the obtained relations; calculation on their basis of the lithological composition of the Bazhenov rocks in the base, as well as in adjacent wells. Results. The article presents the results of an integrated lithological and geophysical interpretation of data from a wide range of electrical and radioactive logging and the results of analytical core studies, on the basis of which a methodological approach to calculating the concentrations of the main rock-forming components of the Bazhenov Formation has been developed. It is based on the identified relationships between the mineral-component composition of rocks and their physical properties. Satisfactory convergence of the calculated values and core data is shown, volumetric lithological models are built for the wells of the Druzhnaya and Povkhovskaya areas. It is shown that the obtained dependences can be used to reliably calculate the lithological composition of the Bazhenov Formation in closely spaced wells that are not characterized by core material. The impossibility of using the proposed methodological approach in thin-layered sections is substantiated due to the fact that the thickness of the interlayers is much less than the resolving power of geophysical borehole probes.
We study how the sizes and radial profiles of galaxies vary with wavelength, by fitting Sérsic functions simultaneously to imaging in nine optical and near-infrared bands. To quantify the wavelength ...dependence of effective radius we use the ratio,
$\mathcal {R}$
, of measurements in two rest-frame bands. The dependence of Sérsic index on wavelength,
$\mathcal {N}$
, is computed correspondingly. Vulcani et al. have demonstrated that different galaxy populations present sharply contrasting behaviour in terms of
$\mathcal {R}$
and
$\mathcal {N}$
. Here we study the luminosity dependence of this result. We find that at higher luminosities, early-type galaxies display a more substantial decrease in effective radius with wavelength, whereas late types present a more pronounced increase in Sérsic index. The structural contrast between types thus increases with luminosity. By considering samples at different redshifts, we demonstrate that lower data quality reduces the apparent difference between the main galaxy populations. However, our conclusions remain robust to this effect. We show that accounting for different redshift and luminosity selections partly reconciles the size variation measured by Vulcani et al. with the weaker trends found by other recent studies. Dividing galaxies by visual morphology confirms the behaviour inferred using morphological proxies, although the sample size is greatly reduced. Finally, we demonstrate that varying dust opacity and disc inclination can account for features of the joint distribution of
$\mathcal {R}$
and
$\mathcal {N}$
for late-type galaxies. However, dust does not appear to explain the highest values of
$\mathcal {R}$
and
$\mathcal {N}$
. The bulge–disc nature of galaxies must also contribute to the wavelength dependence of their structure.
Web applications are ubiquitous, perform mission- critical tasks, and handle sensitive user data. Unfortunately, web applications are often implemented by developers with limited security skills, ...and, as a result, they contain vulnerabilities. Most of these vulnerabilities stem from the lack of input validation. That is, web applications use malicious input as part of a sensitive operation, without having properly checked or sanitized the input values prior to their use. Past research on vulnerability analysis has mostly focused on identifying cases in which a web application directly uses external input in critical operations. However, little research has been performed to analyze the correctness of the sanitization process. Thus, whenever a web application applies some sanitization routine to potentially malicious input, the vulnerability analysis assumes that the result is innocuous. Unfortunately, this might not be the case, as the sanitization process itself could be incorrect or incomplete. In this paper, we present a novel approach to the analysis of the sanitization process. More precisely, we combine static and dynamic analysis techniques to identify faulty sanitization procedures that can be bypassed by an attacker. We implemented our approach in a tool, called Saner, and we applied it to a number of real-world applications. Our results demonstrate that we were able to identify several novel vulnerabilities that stem from erroneous sanitization procedures.
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