Strong Dependence of Infection Profiles on Grouping Dynamics during Epidemiological Spreading

Oxygen impurities may significantly influence the properties of nitride ceramics with a strong dependence on the microstructural distribution of the impurity. For example, amorphous oxygen-rich grain boundary phases are well-known to cause high-temperature mechanical strength degradation in silicon nitride whereas solutionized oxygen is known to decrease the thermal conductivity of aluminum nitride. Microanalytical characterization of these impurities by spectral methods in the AEM is complicated by reactions which form oxygen-rich surface phases not representative of the bulk material. Furthermore, the impurity concentrations found in higher quality ceramics may be too low to measure by EDS or PEELS. Consequently an alternate method for the characterization of impurities in these ceramics has been investigated.Convergent beam electron diffraction (CBED) is a promising technique for the study of impurity distributions in aluminum nitride ceramics. Oxygen is known to enter into stoichiometric solutions with AIN with a consequent decrease in lattice parameter.

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What Does Rent Give to Federal Budget (on the Russia's Budget Dependence upon "Oil Dollars")

Voprosy Ekonomiki ◽

10.32609/0042-8736-2004-7-51-69 ◽

2004 ◽

pp. 51-69 ◽

Cited By ~ 2

Author(s):

E. Sharipova ◽

I. Tcherkashin

Keyword(s):

Oil And Gas ◽

Strong Dependence ◽

Oil Prices ◽

Federal Budget ◽

Oil And Gas Industry ◽

Gas Industry ◽

Resource Rent ◽

Tax Legislation ◽

Russian Economy ◽

The Government

Federal tax revenues from the main sectors of the Russian economy after the 1998 crisis are examined in the article. Authors present the structure of revenues from these sectors by main taxes for 1999-2003 and prospects for 2004. Emphasis is given to an increasing dependence of budget on revenues from oil and gas industries. The share of proceeds from these sectors has reached 1/3 of total federal revenues. To explain this fact world oil prices dynamics and changes in tax legislation in Russia are considered. Empirical results show strong dependence of budget revenues on oil prices. The analysis of changes in tax legislation in oil and gas industry shows that the government has managed to redistribute resource rent in favor of the state.

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The Risks of Russia's Debt Policy against the Background of the Global Debt Crisis

Voprosy Ekonomiki ◽

10.32609/0042-8736-2012-3-80-97 ◽

2012 ◽

pp. 80-97

Author(s):

B. Kheifets

Keyword(s):

Debt Crisis ◽

Strong Dependence ◽

Domestic Debt ◽

Debt Market ◽

State Paternalism ◽

High Level ◽

External Borrowing ◽

Pension Liabilities ◽

Policy Problems ◽

Debt Policy

The paper discusses the debt component of the current global crisis, which becomes stronger in 2011—2012. The Russian economy is analyzed in terms of its debt stability: a thorough analysis shows that it is not quite adequate. This paper presents the main problems that could be exacerbated by the global debt crisis (strong dependence of the budget on the volatility of oil prices, deterioration of conditions for external borrowing and overheat of the domestic debt market, too high public pension liabilities, substantial corporate debt and high level of state paternalism in regard to big business). Some measures to address Russian debt policy problems are proposed.

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Microhardness Testing on Via Fill Material for Via In Pad Technology

ISTFA 2003: Conference Proceedings from the 29th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2003p0209 ◽

2003 ◽

Author(s):

Norman J. Armendariz ◽

Carolyn McCormick

Keyword(s):

Printed Circuit Board ◽

Failure Modes ◽

Strong Dependence ◽

Circuit Board ◽

Electrical Performance ◽

Gravimetric Analysis ◽

Passive Components ◽

Root Cause ◽

Fill Material ◽

Signal Routing

Abstract Via in pad PCB (Printed Circuit board) technology for passive components such as chip capacitors and resistors, provides the potential for improved signal routing density and reduced PCB area. Because of these improvements there is the potential for PCB cost reduction as well as gains in electrical performance through reduced impedance and inductance. However, not long after the implementation, double digit unit failures for solder joint electrical opens due to capacitor “tombstoning” began to occur. Failure modes included via fill material (solder mask) protrusion from the via as well as “out gassing” and related “tombstoning.” This failure analysis involved investigating a strong dependence on PCB supplier and, less obviously, manufacturing site. Other factors evaluated included via fill material, drill size, via fill thermal history and via fill amount or fill percent. The factor most implicated was incomplete cure of the via fill material. Previous thermal gravimetric analysis methods to determine level of polymerization or cure did not provide an ability to measure and demonstrate via fill cure level in small selected areas or its link to the failures. As a result, there was a metrology approach developed to establish this link and root-cause the failures in the field, which was based on microhardness techniques and noncontact via fill measuring metrologies.

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Investigation of 18 physiologically dormant Australian native species: germination response, environmental correlations and the implications for conservation

Seed Science Research ◽

10.1017/s0960258520000422 ◽

2020 ◽

pp. 1-9

Author(s):

Justin C. Collette ◽

Mark K.J. Ooi

Keyword(s):

Native Species ◽

Strong Dependence ◽

Ex Situ ◽

Source Population ◽

Seasonal Temperature ◽

Environmental Correlations ◽

Rainfall Season ◽

Germination Response ◽

Rainfall Seasonality ◽

Germination Experiments

Abstract For physiologically dormant (PD) species in fire-prone environments, dormancy can be both complex due to the interaction between fire and seasonal cues, and extremely deep due to long intervals between recruitment events. Due to this complexity, there are knowledge gaps particularly surrounding the dormancy depth and cues of long-lived perennial PD species. This can be problematic for both in situ and ex situ species management. We used germination experiments that tested seasonal temperature, smoke, dark and heat for 18 PD shrub species distributed across temperate fire-prone Australia and assessed how germination was correlated with environmental factors associated with their home environments. We found extremely high levels of dormancy, with only eight species germinating above 10% and three species producing no germination at all. Seven of these eight species had quite specific seasonal temperature requirements and/or very strong responses to smoke cues. The maximum germination for each species was positively correlated with the mean temperature of the source population but negatively correlated with rainfall seasonality and driest months. The strong dependence on a smoke cue for some of the study species, along with examples from other studies, provides evidence that an obligate smoke response could be a fire-adapted germination cue. Germination response correlated with rainfall season of the source populations is a pattern which has often been assumed but little comparative data across sites with different rainfall seasonality exists. Further investigation of a broader range of species from different rainfall season environments would help to elucidate this knowledge gap.

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High Voltage Electric Discharge for Recovery of Chlorogenic Acid from Tobacco Waste

Sustainability ◽

10.3390/su13084481 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4481

Author(s):

Marija Banožić ◽

Antun Jozinović ◽

Jovana Grgić ◽

Borislav Miličević ◽

Stela Jokić

Keyword(s):

Chlorogenic Acid ◽

Process Parameters ◽

Electric Discharge ◽

High Voltage ◽

Treatment Time ◽

Strong Dependence ◽

Extraction Procedure ◽

Polynomial Equation ◽

Experimental Conditions ◽

Tobacco Waste

Three fractions of tobacco waste (scrap, dust and midrib) were subjected to a high voltage electric discharge (HVED) assisted extraction procedure under different experimental conditions: solvent:solid ratio (300, 500, 700 mL/g), frequency (40, 70, 100 Hz) and treatment time (15, 30, 45 min), in order to study the influence of these conditions on the content of chlorogenic acid. The content of chlorogenic acid ranged from 1.54 to 3.66 mg/100 g for scrap, from 1.90 to 2.97 mg/100 g for dust, and from 2.30 to 3.38 mg/100 g for midrib extract, showing a strong dependence on the applied process parameters. The temperature change and the change in pH and electrical conductivity of the extracts after high voltage discharge treatment were also observed. The studied process parameters showed a statistically significant effect on the chemical and physical properties of the extracts from tobacco waste as well as on the content of chlorogenic acid, indicating the potential of HVED assisted processes in the separation of chlorogenic acid from tobacco industry waste. Multiple regression analysis was used to fit the results for the chlorogenic acid to a second order polynomial equation and the optimum conditions were determined.

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Optimisation on Thermoforming of Biodegradable Poly (Lactic Acid) (PLA) by Numerical Modelling

Polymers ◽

10.3390/polym13040654 ◽

2021 ◽

Vol 13 (4) ◽

pp. 654

Author(s):

Huidong Wei

Keyword(s):

Lactic Acid ◽

Numerical Modelling ◽

Temperature Profile ◽

Food Packaging ◽

Strong Dependence ◽

Viscoelastic Model ◽

Poly Lactic Acid ◽

Strain History ◽

Optimal Temperature ◽

Broad Perspective

Poly (lactic acid) (PLA) has a broad perspective for manufacturing green thermoplastic products by thermoforming for its biodegradable properties. The mechanical behaviour of PLA has been demonstrated by its strong dependence on temperature and strain rate at biaxial deformation. A nonlinear viscoelastic model by the previous study was employed in a thermoforming process used for food packaging. An optimisation approach was developed by achieving the optimal temperature profile of specimens by defining multiple heating zones based on numerical modelling with finite element analysis (FEA). The forming process of a PLA product was illustrated by modelling results on shape evolution and biaxial strain history. The optimal temperature profile was suggested in scalloped zones to achieve more even thickness distribution. The sensitivity of the optimal results was addressed by checking the robustness under perturbation.

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Transitioning of Steel Producers to the Steelworks 4.0 –Literature Review with Case Studies

Energies ◽

10.3390/en14144109 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4109

Author(s):

Bożena Gajdzik ◽

Radosław Wolniak

Keyword(s):

Literature Review ◽

Case Studies ◽

Steel Industry ◽

Industry 4.0 ◽

Strong Dependence ◽

Industrial Robots ◽

Basic Material ◽

Sources Of Information ◽

Important Place ◽

Steel Mills

The publication presents a picture of modern steelworks that is evolving from steelworks 3.0 to steelworks 4.0. The paper was created on the basis of secondary sources of information (desk research). The entire publication concerns the emerging opportunities for the development of the steel producers to Industry 4.0 and the changes already implemented in the steel plants. The collected information shows the support environment for changes in the steel sector (EU programs), the levels of evolution of steel mills, along with the areas of change in the steel industry and implemented investment projects. The work consists of a theoretical part based on a literature review and a practical part based on case studies. The work ends with a discussion in which the staged and segmented nature of the changes introduced in the analyzed sector is emphasized. Based on the three case studies described in the paper, a comparative analysis was conducted between them. When we tried to compare methods used in the three analyzed steel producers (capital groups): ArcelorMittal, Thyssenkrupp, and Tata Steel Group, it can be seen that in all organizations, the main problem connected with steelworks 4.0 transition is the digitalization of all processes within an organization and in the entire supply chain. This is realized using various tools and methods but they are concentrated on using technologies and methods such as artificial intelligence, drones, virtual reality, full automatization, and industrial robots. The effects are connected to better relations with customers, which leads to an increase in customer satisfaction and the organizations’ profit. The steel industry will undergo further strong changes, bringing it closer to Industry 4.0 because it occupies an important place in the economies of many countries due to the strong dependence of steel producers on the markets of the recipients (steel consumers). Steel is the basic material needed to make many products, and its properties have been valued for centuries. In addition, steel mills with positive economic, social, and environmental aspects are part of the concept of sustainability for industries and economies.

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Microstructure and Mechanical Performance of Resistance Spot Welded Martensitic Advanced High Strength Steel

Processes ◽

10.3390/pr9061021 ◽

2021 ◽

Vol 9 (6) ◽

pp. 1021

Author(s):

Yunzhao Li ◽

Huaping Tang ◽

Ruilin Lai

Keyword(s):

Mechanical Properties ◽

Failure Modes ◽

Mechanical Performance ◽

Strong Dependence ◽

High Strength ◽

Weld Nugget ◽

Resistance Spot ◽

Pull Out ◽

Cross Tension ◽

Spot Welded

Resistance spot welded 1.2 mm (t)-thick 1400 MPa martensitic steel (MS1400) samples are fabricated and their microstructure, mechanical properties are investigated thoroughly. The mechanical performance and failure modes exhibit a strong dependence on weld-nugget size. The pull-out failure mode for MS1400 steel resistance spot welds does not follow the conventional weld-nugget size recommendation criteria of 4t0.5. Significant softening was observed due to dual phase microstructure of ferrite and martensite in the inter-critical heat affected zone (HAZ) and tempered martensite (TM) structure in sub-critical HAZ. However, the upper-critical HAZ exhibits obvious higher hardness than the nugget zone (NZ). In addition, the mechanical properties show that the cross-tension strength (CTS) is about one quarter of the tension-shear strength (TSS) of MS1400 weld joints, whilst the absorbed energy of cross-tension and tension-shear are almost identical.

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Dipole radiation and beyond from axion stars in electromagnetic fields

Journal of High Energy Physics ◽

10.1007/jhep06(2021)182 ◽

2021 ◽

Vol 2021 (6) ◽

Author(s):

Mustafa A. Amin ◽

Andrew J. Long ◽

Zong-Gang Mou ◽

Paul M. Saffin

Keyword(s):

Electromagnetic Fields ◽

Parametric Resonance ◽

Coupling Strength ◽

Coupling Parameter ◽

Strong Dependence ◽

Dipole Radiation ◽

Large Coupling ◽

External Electromagnetic Fields ◽

Order Of Magnitude ◽

Dimensionless Coupling

Abstract We investigate the production of photons from coherently oscillating, spatially localized clumps of axionic fields (oscillons and axion stars) in the presence of external electromagnetic fields. We delineate different qualitative behaviour of the photon luminosity in terms of an effective dimensionless coupling parameter constructed out of the axion-photon coupling, and field amplitude, oscillation frequency and radius of the axion star. For small values of this dimensionless coupling, we provide a general analytic formula for the dipole radiation field and the photon luminosity per solid angle, including a strong dependence on the radius of the configuration. For moderate to large coupling, we report on a non-monotonic behavior of the luminosity with the coupling strength in the presence of external magnetic fields. After an initial rise in luminosity with the coupling strength, we see a suppression (by an order of magnitude or more compared to the dipole radiation approximation) at moderately large coupling. At sufficiently large coupling, we find a transition to a regime of exponential growth of the luminosity due to parametric resonance. We carry out 3+1 dimensional lattice simulations of axion electrodynamics, at small and large coupling, including non-perturbative effects of parametric resonance as well as backreaction effects when necessary. We also discuss medium (plasma) effects that lead to resonant axion to photon conversion, relevance of the coherence of the soliton, and implications of our results in astrophysical and cosmological settings.

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