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A numerical analysis of a basin-type solar still with a double glass cover is done under winter circumstances of solar radiation, ambient temperature, and wind speed. Equations defining thermal balances of different components of traditional and double glass cover solar stills are used to describe the physical issue, which is then solved using the Gauss-Seidel numerical technique. The effects of solar radiation, ambient temperature, and wind speed on the daily production, internal efficiency, and overall performance of solar stills are calculated and illustrated. The findings demonstrate that a solar still with a double-glass cover is more productive and efficient than a solar still with a single glass cover.

Dominic H. Gavin’s Fascism and Resistance in Italian Cinema: History, Memory and Identity after 1968 reminds the reader that ‘Italian cinema is one of the country’s postwar success stories; the mem...

“A tessellation is a collection of shapes that fit together without gaps or overlap to cover the infinite mathematical plane.” So begins the opening chapter of this superbly illustrated survey of t...

We investigate the boundedness of Fourier multipliers on a compact Lie group when acting on Triebel-Lizorkin spaces. Criteria are given in terms of the Hörmander-Mihlin-Marcinkiewicz condition. In our analysis, we use the difference structure of the unitary dual of a compact Lie group. Our results cover the sharp Hörmander-Mihlin theorem on Lebesgue spaces and also other historical results on the subject.

Ultrasonic-based techniques allow the prediction of the energy required to break the aggregate and have been more commonly used to measure the stability of aggregates. Although they result in the same applied energy, certain combinations of time and power might correspond to different intensities of cavitation. Consequently, different responses in aggregation indexes can be obtained with different configurations of ultrasound techniques. Thus, this work was carried out to evaluate the effects of cavitation intensity in the distribution of aggregates of a Paleudalf under management systems with cover plants and to compare aggregate stability determination methods (ultrasound versus wet sieving). Aggregate samples of the BS (bare soil), OT (black oat + forage turnips) and OV (black oat + hairy vetch) treatments were exposed to ultrasonic irradiation in different combinations of potency and time: (U1) 74.5 W/4 s; (U2) 49.7 W/6 s; (U3) 74.5 W/10 s and (U4) 49.7 W/15 s. After each sonification, the samples were passed in the same set of sieves used in the standard method of wet sieving -WS (8.00 - 4.76, 4.76 - 2.00, 2.00 - 1.00, 1.00 - 0.25 and < 0.25 mm) and the geometric mean diameter (GMD) and mass-weighted mean diameter (WMD) were calculated. The amplitude of vibration exerted a greater influence on soil breakdown than the total energy applied. Compared to the ultrasound method, in the WS method observed higher percentage of retained aggregates in the size class 8-4.76 mm and, consequently, greater aggregation indexes GMD and WMD.

This study focuses on the relationship between the mainstream press and right-wing protests in Brazil. Guided by the “protest paradigm” literature, my goal was to understand how reporters in the Gl...

We prove #P-completeness results for counting edge colorings on simple graphs. These strengthen the corresponding results on multigraphs from [4] . We prove that for any κ ≥ r ≥ 3 counting κ-edge colorings on r-regular simple graphs is #P-complete. Furthermore, we show that for planar r-regular simple graphs, where r ∈ { 3 , 4 , 5 } , counting edge colorings with κ colors for any κ ≥ r is also #P-complete. As there are no planar r-regular simple graphs for any r > 5 , these statements cover all interesting cases in terms of the parameters ( κ , r ) .

A large number of works are devoted to the development of the skin and hair cover of sheep, depending on their breed affiliation, age, feeding conditions and housing. The authors point out that along with other conditions the quality of wool and wool clip is greatly influenced by the conditions of the feeding of animals. A high level of feeding increases the wool clip and improves the quality of the wool and vice versa a low level reduces, causes thinning and worsens other physical properties of the wool. As is known, one of the significant factors that determine the increase in wool clip is the size of the animal and, consequently, the total area of the skin. The purpose of the research was to investigate the morphological traits of the development of the skin and wool cover in sheep of Prikatunsky meat and wool type. The research material was wool samples from four topographic areas of the animal’s body (side/thigh/back/belly) and skin (side) of different sex and age groups, selected from the animals of the studied groups. In the course of research, the quality of wool and indicators of the histostructure of the skin of Prikatunsky meat and wool type of sheep have been investigated. In terms of thick-haired of wool, replacement rams and gimbers of Prikatunsky meat and wool type of sheep were superior by 4,82 pcs. per mm² or 19,0 % and 4,41 pcs. per mm² or 15,8 % of adult animals, respectively. Balance secondary follicles/primary follicles in young animals were higher by 10,3 and 17,3 % compared to breeding rams and ewes. The wool of the replacement young animals was thinner by 7,28 and 4,78 microns and they were more thick-haired. The obtained data will be used in the mating campaign when mating program rams in order to improve the sheep of Prikatunsky meat and wool type.

The Atlantic Forest in Brazil has been suffering natural and anthropic perturbations over the years, which has been impacting, qualitatively and quantitatively, with different degrees and intensities, its canopy cover. These perturbations can be caused by the selective cut of species, burning, natural death of trees, among several other factors, which act directly on the composition and the floristic diversity of fragments of the forest. The main motivation for conducting this work was to alert about the relevance of the Atlantic forest conservation and the need for a constant monitoring system to preserve what has been left of it. This can be partially achieved by permanently estimating its canopy cover. This paper describes the implementation and evaluation of the descriptors: energy, entropy, homogeneity, contrast and the sum of the high-frequency Discrete Fourier Transform (DFT), for estimating canopy cover based on High Resolution Camera (HRC) satellite images. The analyses carried out based on the results of the experiments showed that the energy descriptor was the best descriptor among those used and, comparatively to the others, obtained the higher correlation (r), determination (R) and significance (p). Based on the experiments, the energy descriptor presented an expressive potential to be used in processes for estimating the canopy cover based on satellite images, in large areas of the semi-deciduous forest.

‘Covering’ previously recorded tracks is a central aspect of popular music. Despite an abundance of examples, discourse related to cover-version tracks is limited and includes questionable application of dichotomizing terminology (‘cover’, ‘version’) that can cause problems for interpreting the cover-version genre and diminish the nuanced approaches taken by artists who produce cover-versions. Examining recordings from the Punk Goes… album series reveals many examples that go beyond the either‐or cover/version dichotomy generally presented in musicology. As such, this article has three main aims: to investigate the ways in which Punk Goes… tracks innovatively move between the poles of cover and version, thus requiring a new analytical framework; to explore the connection between imitation and transformation to the ascription of cover and version; and to move beyond prior musicological scholarship that emphasizes formal elements and composer intention. This article presents a reclassification of the terms ‘cover’ and ‘version’ as extreme poles of a ‘cover-version spectrum’ dependent on the listener’s interpretation of the performative character. Analyses challenge assumptions that equate musical phrases with fixed musical meanings, suggesting instead that the interpreted manner of performance is more significant than syntactical concerns. This provides a structure for clearer examination of cover-versions and supports the view that semiotic methods are a vital tool in the analysis of recorded popular music.

Local scour around piers is one of the primary causes of collapse of bridges that cross rivers. The most severe scouring occurs in cold regions where ice cover significantly changes the velocity profile. Having an accurate estimation of the maximum scour depth around bridge piers, especially in cold regions, is necessary for a safer design of piers. In this study, 3D numerical models are compared to laboratory experiments to examine the process of local scour around bridge piers with and without smooth and rough ice cover. By using the equation of Meyer-Peter and Müller, the sediment transport model is validated to approximate the transport of the sediment particles. Numerical results showed good agreements with experimental observations where the maximum scour depth and turbulent kinetic energy around bridge piers were the highest under rough ice cover conditions.

Understanding the dynamic nature of individual growth in stream-dwelling salmonids may help forecast consequences of climate change on northern fish populations. Here, we performed an experimental capture–mark–recapture study in Atlantic salmon (Salmo salar) to quantify factors influencing wintertime growth variation among juveniles under different scenarios for ice-cover reduction. We applied multiple imputation to simulate missing size observations for unrecaptured fish and to account for individual-level variation in growth rates. The salmon parr exhibited substantial body length shrinkage in early winter, suppressed growth through midwinter, and increased growth rates in late winter and particularly in spring. Unexpectedly, the presence of ice cover had no direct effects on wintertime growth. Instead, our results implied increasing energetic costs with reducing ice cover; individuals exposed to absent or shortened ice-covered period gained mass at a lowered rate in spring, whereas the present, long ice-covered period was followed by rapid growth. This study emphasizes natural resilience of Atlantic salmon to wintertime environmental variation, which may help the species to cope with the reductions in ice-cover duration due to climate change.

International audience; Optical parametric oscillators are versatile devices for generating a tunable coherent radiation from an incident laser beam. They rely on nonlinear frequency conversion to cover spectral ranges that are poorly or not covered by direct laser emission. This article presents a short overview of the optical parametric oscillators principles of operation, main implementations and related applications.

The article describes the possibility of using the granulometric analysis of rock cuttings formed in controlled core scratching tests to estimate the angle of internal friction.The study object is the Kovykta gas-condensate field (GCF) that occupies a wide area in the southeastern part of the Irkutsk amphitheater of the Siberian platform. This uniquely complex geological structure holds significant reserves of hydrocarbons. Its sedimentary cover is composed of the Vendian – lower Paleozoic and partly Riphean formations. Their total thickness exceeds 6000 m, as estimated from the new seismic survey data [Vakhromeev et al., 2019].The sedimentary cover of the Kovykta GCF has been studied by surface and borehole geophysical techniques, remote sensing and geostructural methods, in combination with the tectonophysical approach [Seminsky et al., 2018] based on drilling data, including standard and special core sampling data.

Global Frechet regression is an extension of linear regression to cover more general types of responses, such as distributions, networks, and manifolds, which are becoming more prevalent. In such m...

В 2021 году А.А. Драгуновым при помощи системно-геодинамического дешифрирования были выявлены Восточно-Оренбургский и Западно-Оренбургский геодинамически активные очаги генерации углеводородов Оренбургского нефтегазоконденсатного месторождения. Было предположено, что ряд малых залежей юго-запада Оренбургской области также получают от них подпитку. Целью представленной работы являлась попытка проследить вышеуказанные очаги генерации углеводородов в фундаменте и осадочном чехле на основе переинтерпретации временных разрезов региональных сейсмических профилей. Методы работы. Выделение тектонических нарушений проводилось вручную с применением авторских методических приемов приближений и последовательной детализации. После чего выполнялось системное обобщение и анализ полученных результатов в свете перспектив нефтегазоносности юго-запада Оренбургской области. Результаты работы. В результате работ было рассмотрено глубинное строение очагов, отмечены сейсмогеологические особенности их обнаружения. В местах картирования очагов генерации на временных разрезах зафиксированы неотектонические разломы «цветкового» типа, хаотическая вертикально направленная локально усиленная сейсмическая запись под ними ниже отражающего горизонта, отождествляемого с породами фундамента. Прослежена связь глубинных разломов и связанных с ними новейших оперяющих разломов с солянокупольными структурами кунгурского возраста. По результатам комплексного геологического анализа структурных построений выявлена схематическая сеть неотектонических разломов фундамента, судя по которой, Оренбургское нефтегазоконденсатное месторождение и другие, более мелкие месторождения углеводородов и выявленные сейсморазведочными работами структуры юго-запада Оренбургской области имеют закономерное распределение внутри крупной радиально-концентрической структуры диаметром около 180 км. Данная структура, вероятно, представляет собой зону разуплотнения в фундаменте, в пределах которой в осадочном чехле образовались перспективные в плане нефтегазоносности структуры. Уникальное и самое крупное в пределах юго-запада Оренбургской области Оренбургское месторождение находится в центре макроструктуры, являясь, возможно, результатом работы главных очагов генерации УВ в фундаменте. Вдоль радиальных и концентрических разломов сосредоточены более мелкие месторождения углеводородов. Кроме того, Оренбургское месторождение приурочено к зоне наложения двух концентров, что, возможно, является значительным фактором при обнаружении крупных месторождений. В качестве выводов даны рекомендации для дальнейших исследований и поиска возможных геодинамически активных очагов генерации углеводородов в пределах Русской платформы In 2021, A.A. Dragunov, using system-geodynamic decoding, identified the East-Orenburg and West-Orenburg geodynamically active centers of hydrocarbon generation of the Orenburg oil and gas condensate field. It was assumed that a number of small deposits in the south-west of the Orenburg region also receive recharge from them. The aim of the presented work was an attempt to trace the above-mentioned sources of hydrocarbon generation in the foundation and sedimentary cover on the basis of reinterpretation of time sections of regional seismic profiles. Methods. The selection of tectonic disturbances was carried out manually using the author's methodological techniques of approximations and sequential detailing. After that, a systematic generalization and analysis of the results obtained was carried out in the light of the prospects for oil and gas potential of the south-west of the Orenburg region. Results. As a result of the work, the deep structure of the foci was considered, the seismogeological features of their detection were noted. Neotectonic faults of the "flower" type, chaotic vertically directed locally enhanced seismic recording under them below the reflecting horizon identified with the basement rocks were recorded in the places of mapping the generation centers on time sections. The connection of deep faults and the newest feathering faults associated with them with salt-dome structures of the Kungur age is traced. According to the results of a comprehensive geological analysis of structural structures, a schematic network of neotectonic basement faults has been identified, judging by which the Orenburg oil and gas condensate field and other smaller hydrocarbon deposits and the structures identified by seismic surveys in the southwest of the Orenburg region have a regular distribution within a large radial-concentric structure with a diameter of about 180 km. This structure probably represents a zone of decompression in the foundation, within which promising structures in terms of oil and gas potential were formed in the sedimentary cover. The Orenburg deposit, which is unique and the largest within the south-west of the Orenburg Region, is located in the center of the macrostructure, possibly being the result of the work of the main centers of HC generation in the foundation. Smaller hydrocarbon deposits are concentrated along the radial and concentric faults. In addition, the Orenburg field is confined to the zone of overlap of two concenters, which is probably a significant factor in the discovery of large deposits. As conclusions, recommendations are given for further research and search for possible geodynamically active centers of hydrocarbon generation within the Russian platform.

A many-to-many [Formula: see text]-disjoint path cover ([Formula: see text]-DPC) of a graph [Formula: see text] is a set of [Formula: see text] vertex-disjoint paths joining [Formula: see text] distinct pairs of source and sink in which each vertex of [Formula: see text] is contained exactly once in a path. The balanced hypercube [Formula: see text], a variant of the hypercube, was introduced as a desired interconnection network topology. Let [Formula: see text] and [Formula: see text] be any two sets of vertices in different partite sets of [Formula: see text] ([Formula: see text]). Cheng et al. in [Appl. Math. Comput. 242 (2014) 127–142] proved that there exists paired many-to-many 2-disjoint path cover of [Formula: see text] when [Formula: see text]. In this paper, we prove that there exists unpaired many-to-many [Formula: see text]-disjoint path cover of [Formula: see text] ([Formula: see text]) from [Formula: see text] to [Formula: see text], which has improved some known results. The upper bound [Formula: see text] is best possible in terms of the number of disjoint paths in unpaired many-to-many [Formula: see text]-DPC of [Formula: see text].

Remotely sensed ground cover data play an important role in Australian rangelands research development and extension, reflecting broader global trends in the use of remotely sensed data. We tested the relationship between remotely sensed ground cover data and field-based assessments of grazing land condition in the largest quantitative analysis of its type to date. We collated land condition data from 2282 sites evaluated between 2004 and 2018 in the Burdekin and Fitzroy regions of Queensland. Condition was defined using the Grazing Land Management land condition framework that ranks grazing land condition on a four point ordinal scale based on dimensions of vegetation composition, ground cover level and erosion severity. Nine separate ground cover derived indices were then calculated for each site. We found that all indices significantly correlated with grazing land condition on corresponding sites. Highest correlations occurred with indices that benchmarked ground cover at the site against regional ground cover assessed over several years. These findings provide some validation for the general use of ground cover data as an indicator of rangeland health/productivity. We also constructed univariate land condition models with a subset of these indices. Our models predicted land condition significantly better than random assignment though only moderately well; no model correctly predicted land condition class on >40% of sites. While the best models predicted condition correctly at >60% of A and D condition sites, condition at sites in B and C condition sites was poorly predicted. Several factors limit how well ground cover levels predict land condition. The main challenge is modelling a multidimensional value (grazing land condition) with a unidimensional ground cover measurement. We suggest that better land condition models require a range of predictors to address this multidimensionality but cover indices can make a substantial contribution in this context.

At present, 264 species of lichens and allied fungi have been recorded for the territory of the BotanicalGarden of Petrozavodsk State University (Republic of Karelia) and 112 species have been found in its arboretum, wheremore than 200 species of introduced trees grow. The paper presents the results of studying the features of the epiphyticlichen cover of the collection trees of the arboretum of the Botanical Garden of PetrSU (Republic of Karelia). Results of thestudy are based on 1662 descriptions of the epiphytic lichen cover on 209 trees of coniferous species and 1150 descriptions –on 143 deciduous introduced species.The average total projective cover of lichens on the trunks of the studied coniferous introduced species reaches 18 % atthe trunk base, and 19 % – at a height of 130 cm above the ground. The number of species in the descriptions of epiphyticlichen cover varies from 0 to 12 (0.8 in average). The highest values of the projective cover of lichens and the numberof species in the descriptions were observed on the trunks of conifers of the genus Pinus, the lowest – on the trunks oftrees of the genus Thuja. The average total projective cover of lichens on the trunks of the studied deciduous introducedspecies was 8 % at the base, and 25 % – at a height of 130 cm above the ground. The number of species in the descriptionvaries from 0 to 9 (1.0 in average). The highest values of the projective cover of lichens and the number of species in thedescription are noted on the trunks of the genus Quercus, the lowest – on the trunks of trees of the genus Ulmus. Collectiontrees of arboretum tree represent a model object for observing the features of the formation of the epiphytic lichen cover

This essay focuses on the 16th -century Bolognese naturalist and collector Ulisse Aldrovandi (1522-1605) and his enormous image collection of naturalia. Do these images present a specifically Bolognese form of visual natural science, and was his visual format of truthfulness new at the time? Did Local visual culture leave clear marks on Aldrovandi's image collection? On cover:ANNIBALE CARRACCI (BOLOGNA 1560 - ROME 1609), An Allegory of Truth and Time c. 1584-1585.Oil on canvas | 130,0 x 169,6 cm. (support, canvas/panel/str external) | RCIN 404770Royal Collection Trust / © Her Majesty Queen Elizabeth II 2021.

The articles in this issue cover various aspects of economic theory, practice, and policy: and the important link between these categories, not least the importance of having realistic and appropri...

To classify an image, traditional classifiers depend mainly on the spectral and/or textural distinctions between different land-cover units, while this study attempts to explore the properties of s...

This special issue of CFPJ has introduced systemism, a graphic approach to the study of Canadian foreign policy and International Relations (IR). It is beyond the scope of this final essay to cover...

There is a similarity in dynamics and a quantitative difference in the ice cover regime in four consecutive 30-year periods: 1961–1990, 1971–2000, 1981–2010, 1991–2020 are noted. The greatest differences are observed in the regime characteristics of the first and the last periods. The absolute maximum or minimum recorded in at least one of the months from January to May determines the nature of the ice cover of the entire ice season. The sensitivity of the predictive physical-statistical model to the replacement of climatic norms has been investigated. Estimates of the quality of forecasts of the average monthly ice cover are obtained. Keywords: base period, long-term forecast, physical and statistical model, ice cover, climate characteristics, typification, forecast skill scores

Reinforced concrete (RC) in aggressive environments has higher concrete clear cover provided to protect the reinforcement against corrosion. However, providing such higher cover in severe environments could result in increased crack widths for the structural member. Hence, using a combination of fibre-reinforced polymer (FRP) bars and steel reinforcement bars (hybrid reinforcement) has been considered as a suitable solution to develop the full flexural capacity of the section without significantly affecting the serviceability and ductility requirements. This includes utilising the non-corrodible nature of FRP by adding a layer of longitudinal reinforcement made of FRP bars at the corner areas of the cross-section and keeping the main steel reinforcement at sufficient cover depth. This paper studies the flexural behaviour of hybrid glass-fibre-reinforced polymer (GFRP) beams consisting of continuous GFRP bars along with conventional steel reinforcement and comparing them with conventional RC beams through experimental and analytical studies. The test results indicated that the hybrid GFRP beams possess better flexural strength and ductility compared to conventional RC beams and could be considered as a suitable alternative to replace RC beams in aggressive environments.

Ice cover on lakes is subject to atmospheric forcing from above and the influence of water dynamics and heat flux from below. One characteristic example of these influences in some large lakes, such as Lake Baikal in Russia, are the giant ice rings and the associated eddies under the ice cover. In April 2020 a giant ice ring appeared in southern Baikal, and a lens-like eddy was detected below the ice. We analysed the temporal changes of ice cover using satellite images from multiple satellite missions – MODIS on Terra and Aqua, Sentinel-1 SAR, Sentinel 2 MSI, Landsat 8, PlanetScope, satellite photography from the International Space Station, and radar altimetry data from Jason-3. Satellite imagery and meteorological data show unusual temporal changes of ice colour in April 2020, which were explained by water infiltration into the ice followed by the competing influences of cold air from above and the warm eddy below the ice. Tracking of ice floe displacement also makes it possible to estimate eddy currents and their influence on the upper water layer. Multi-satellite data contribute to a better understanding of the development of ice cover in the presence of eddies, the role of eddies in horizontal and vertical heat and mass exchange, and their impact on the chemistry and biology of the lakes and on human activity.

The Racecourse Cu-Au porphyry prospect is found within the Macquarie Arc of the Lachlan Fold Belt, in the Lachlan Transverse Zone, a cross-arc structure hosting significant world-class mineralization, including the Cadia and Northparks districts. Several geochemical and geophysical surveys of the prospect have been complimented by a total of 19,819 m of drilling, with only four holes reaching a depth greater than 300 m. Positive lithogeochemistry (fertility indices, comparisons with the Cadia and Northparks systems) subtle alteration, and mineralized intercepts indicate heightened mineral potential, yet the prospect has lacked a comprehensive geochemical survey outlining the extent of the mineralized target at surface. Soil samples and Monterey pine (Pinus radiata) tree cores were collected above and distal to mineralization intercepted by prior drilling in order to outline the ore deposit footprint and test the viability of dendrogeochemistry as an exploration tool for porphyry Cu mineralization. Ultimately, this study documented the spatial extent of the Racecourse target and identified potential areas for additional Cu mineralization. Soil samples were separated with the

When scanning fresh ice cover in the microwave range at a frequency of 13 GHz, the transmitted radiation power was investigated at four linear polarizations (vertical, horizontal, and polarizations rotated at an angle of +-45) for a long period of time. The measurements were carried out on the ice cover of the lake. Arakhley (Transbaikal region) at a distance of 120 m from the coast in March 2021. We also measured the external parameters of the studied environment, namely, the temperature of the ice cover, meteorological parameters (wind speed, air temperature, pressure). The distance between the generator and the receiver of electromagnetic radiation was 40 meters. The orientation of the instruments is West-East. As a result, variations in the power of the transmitted microwave radiation were detected. These variations are related to the temperature deformations of the ice cover, which were recorded using a deformation sensor installed in the ice cover. Also revealed a feature that was observed earlier in the spring. This is a different temporal behavior of the first Stokes parameter, which is determined by the sum of the powers of two orthogonal polarizations, namely, the sum of the received signals at the vertical and horizontal polarizations, and the sum of the received signals of the two polarizations rotated at an angle of +45 and -45. This difference is also associated with temperature deformations of the fresh ice cover in the spring. Keywords: microwave range, fresh ice cover, Stokes parameters, temperature deformation

Urban trees provide people with a range of ecosystem services. Trees planted along streets have been a large focus of urban forest research and practice, and municipalities invest significant resources in their survival. However, the optimal spacing of street trees is not addressed in the scientific literature, and existing municipal street tree spacing standards are highly variable and poorly enforced. In this study, we examine variability in crown shape and size for street trees to test for possible interaction effects at closer spacings. We measured variability in crown diameters both parallel and perpendicular to street tree rows to test whether changes in crown dimensions can be explained by interaction effects with neighbouring trees, and whether crown interactions lead to a reduction in total crown projection area (i.e., canopy cover). We measured the crown dimensions and diameter at breast height of 1,338 street trees in Halifax, Canada. We used two-way analysis of variance to test whether crown shape and crown projection area were affected by crown interactions and spacing. We found that the effect of narrower spacing and interactions (i.e., crowns touching/overlapping) among trees translated to crowns extending away from the direction of interaction. We also found that these changing crown dimensions were associated with increases in canopy cover. Urban forest ecosystems are a vital resource for the increasingly urban population. There is a need for empirical research on spacing standards and practices that investigate their influence on the supply of ecosystem services, such as stormwater retention, air pollution removal, and cooling.

The results of analytical calculations of T-joints in process pipelines in conformity with GOST 32388-2013, GOST 34233.3-2017, and ASME B31.3-2002 regulatory documents are compared. A numerical study of stresses at T-joints was conducted using finite-elements method. Data were obtained on the influence of dimensions of cover rings on reinforcement of T-joint in pipelines. The results of numerical and analytical calculations of T-joints are compared.

The mechanical behaviour of soils overlying weathered bedrock is often a concern when it comes to the risk of sinkhole occurrence. Cavities often form near the interface between cover soil and fissured bedrock and propagate upwards with internal soil erosion, ultimately resulting in surface collapse known as sinkhole. This paper presents and discusses the mechanical behaviour of sinkholes by investigating the stability associated with the size and depth of the cavity. The two failure modes considered in this study correspond to tensile failure and excessive yielding around a subsurface cavity. Numerical modelling with the finite-difference software Flac was employed to determine the stress distributions and deformations around the cavity. The results of numerical analyses were used to quantify the effects of factors affecting sinkholes such as bedrock depth, cavity size, overburden thickness and soil strength. The results also illustrate the yielding behaviour, which is related to a cover-subsidence sinkhole with a gradual depression over time but no structural collapse. The analysis result shows that the critical overburden thickness of around 25 m turns the yielding condition from unstable to stable.

We consider a generalization of Baum-Katz theorem for random variables satisfying some cover conditions. Consequently, we get the results for many dependent structures, such as END, ϱ*-mixing, ϱ−-mixing and φ-mixing, etc.

The Future of Teaching is, as posited on the cover, ‘a timely tour de force.’ It is, however, marred by Claxton’s (2021) vituperative railing across ten chapters that incites regression to the ‘vit...

Square-rebars have been used in many historical reinforced concrete buildings worldwide. The durability and structural behavior of such historical buildings should be evaluated regularly and accura...

The production of hydrogen via water electrolysis using renewable electricity is a promising carbon-neutral technology. In this contribution, we report insights into the hydrogen evolution reaction (HER) in H2SO4 on Pt(111) and graphene-covered Pt(111), in addition to the electrochemical properties of graphene overlayers. As-prepared graphene overlayers are selectively permeable to H+ ions in the electrolyte, allowing H+ ions into the confined layer between graphene and Pt(111) while excluding SO42- and other anions. We demonstrate that defects in these as-prepared graphene overlayers can be generated from oxidation at high overpotentials or reduction from the production of H-2 bubbles and postulate that HER occurs locally at only Pt(111) in the proximity of defects in graphene overlayers on asprepared G/Pt(111) electrodes, and as defects in graphene increases, more of the Pt(111) surface becomes utilized for HER. Kinetically, the addition of defective graphene overlayers can increase the geometric HER rate by up to 200%, while Tafel slopes and [H+] reaction orders remain unchanged. These results shed kinetic insight into the nature of graphene overlayers and their effect on HER catalysis and also demonstrate the promise of confinement modifications in designing catalysts with properties closer to achieving optimum rates.

Path cover is a well-known intractable problem that finds a minimum number of vertex disjoint paths in a given graph to cover all the vertices. We show that a variant, in which the objective is to minimize the number of length-0 paths, is polynomial-time solvable. We further show that another variant, to minimize the total number of length-0 and length-1 paths, is also polynomial-time solvable. Both variants find applications in approximating the two-machine flow-shop scheduling problem in which job processing has constraints that are formulated as a conflict graph. For the unit jobs, we present a 4/3-approximation for the scheduling problem with an arbitrary conflict graph, based on the exact algorithm for the above second variant of the path cover problem. For arbitrary jobs where the conflict graph is the union of two disjoint cliques, we present a simple 3/2-approximation algorithm.