bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of the freight transportation system within the raw material enterprises
Authors: Trofimova Liudmila , Pantina Tatiana , Pevnev Nikolay , Borodulina Svetlana , Trofimov Boris
Published: November 2021

The article presents the results of a study to establish the relationship between the planned indicators formed in the operational work of the road transport enterprise when transporting goods and the indicators formed in the current work. The authors consider the functioning of a road transport enterprise in the current mode on the methodological basis of the theory of road freight transport, the theory of rolling stock maintenance, the system approach, using economic and mathematical methods. The criterion for optimising planning is the profit of the road transport company, and the constraints are the output, mileage and labour intensity of maintaining the rolling stock, which depends on the probability values of the length of the ride with freight, the mass of the freight, average technical speed and time for loading and unloading. The application of the developed methods and mathematical model to optimise planning will make it possible to study the functioning of a road transport enterprise as a probabilistic system and to determine planning indicators, considering the influence of random factors that appear in the current and operational work of the road transport enterprise.
Influence of immersion depth of the sheet pile on the intensity of suffusion processes in pressure hydraulic structures
Authors: Bik Iurii , Degtiareva Vera , Pridanova Oksana , Kudriashov Aleksandr , Dubrovin Ruslan
Published: November 2021

The research examines the influence of constructive features of a pressure hydraulic structure on the intensity of suffusion processes in the tailwater. The equations of non-vortex filtration fluid motion under a hydraulic structure in the form of a sheet pile wall are calculated by the finite element method using the Neumann and Dirichlet boundary conditions. The influence of immersion depth of the sheet pile on the erosion processes in the tailwater is investigated. The possibility of protecting the pressure head structure by creating an apron in the tailwater which prevents soil suffusion is analyzed. Calculations show that the greatest pressure gradients are observed at the sheet pile tip and at the outlet to the tailwater. From the point of view of the suffusion process, the zone at the lower end of the sheet pile is not dangerous; therefore, predictions about the suffusion intensity for a particular structure should be made on the basis of the output gradients at the tailwater border. Calculations show that the constructive features of a pressure hydraulic structure have a significant impact on the processes of suffusion and pile heave. The graphs are based on the calculation results; they clearly demonstrate that the filtration rate in the structure tailwater sharply decreases with an increase in the depth of driving the sheet pile, regardless of the soil type of the structure base. Besides, an additional protective effect is provided by a structure in the apron tailwater.
A deteriorating food preservation supply chain model with downstream delayed payment and upstream partial prepayment
Authors: Ghosh Prasanta Kumar , Kumar Manna Amalesh , Dey Jayanta Kumar , Kar Samarjit
Published: November 2021

This paper investigates a food supply chain model consisting of the supplier, food producer and multi-retailer of a deteriorating item under fully delay-in-payment and partial advance payment scheme. The deterioration rate of raw material is dependent on temperature and other environmental factors with respect to time. Here, the food producer prepares food after collecting the raw material from the supplier and then storing it in cold storage. The refrigeration cost is dependent on the occupied volume in the cold storage (where the products are preserved for freshness) and power consumption. The supplier offers delay-in-payment to stimulate the food producer to buy more raw material (which minimizes the holding cost and earns more revenues), whereas the food producer takes the partial advance payment on purchase cost from the retailers to ensure the order quantity. A mathematical model is developed to obtain optimal production time and the optimal number of deliveries so that the average profit of the food producer is maximum. Finally, a numerical example and sensitivity analysis of the key parameters are provided to illustrate and test the feasibility of the proposed model.
Designing a single-vendor and multiple-buyers’ integrated production inventory model for interval type-2 fuzzy demand and fuzzy rule based deterioration
Authors: Rout Chayanika , Kumar Ravi Shankar , Paul Arjun , Chakraborty Debjani , Goswami Adrijit
Published: November 2021

In this paper, a single-vendor and multiple-buyers’ integrated production inventory model is investigated where demand of the item at the buyers’ location is considered as interval type-2 fuzzy number (IT2FN). Deterioration rate of the item is assumed to change in accordance with the weather conditions of a particular region. It relies upon the values of certain attributes that have a direct influence on the extent of deterioration. These parameter values are easily forecasted and thereby can be utilized to determine the item depletion rate, which is executed here using Mamdani fuzzy inference scheme. Besides, a nearest interval approximation formula for the defuzzification of IT2FN is developed and applied in the proposed integrated production inventory model. The model optimizes the total number of shipments to be made to the buyers within a complete cycle so as to minimize the overall integrated cost incurred. A detailed illustration of the theoretical results is further demonstrated with the help of numerical example, followed by sensitivity analysis which provides insights into better decision making.
Iron Ore Use as a Potential of Sustainable Development of Industrial Regions of Ukraine: Aspects of Environmental Taxation
Authors: Hromozdova Larysa , Bodyuk Adam , Makhortov Uriy , Baranik Zoya , Khamska Nelina , Kukhar Nina , Adami Carlo
Published: November 2021

The article investigates the resources potential of Ukraine, which is not used effectively enough for the needs of sustainable economic development of industrial regions. The article aims to identify ways to increase the eco-tax base in order to improve the budget support for sustainable development of the iron ore subsoil use and synergetic development of industrial regions of Ukraine. The normative-legal base of subsoil users' taxation is investigated. The necessity of ecological taxation is substantiated as the consequence of enterprise activity is actual environmental pollution. Applied innovations in the method of calculating the environmental tax are proposed. They consider the factor of ownership of natural resources and the discount change in their value over time, which will ultimately increase tax revenues to the budget. It is recommended to introduce the author's approach in the methods of calculating the environmental tax in the field of iron ore subsoil use, which synergistically affects the development of industrial regions of Ukraine. It is justified that the COVID - crisis is a heavy burden on local and state budgets. Therefore, it is necessary to further optimize the system of environmental taxation in order to increase environmental contributions to the budget.
The Gravity of Cryptocurrency and Prospects in a Post-Pandemic Economy
Authors: Abuselidze George , Zoidze Gia
Published: November 2021

Today, everything in the world is changing rapidly; businesses that ten years ago may not have existed at all now exist and bring with them a significant income. Change in almost every field has one key feature: it is digitalisation. There are innovations in payment methods as well; the most high-profile issue in recent years in this regard is the emergence of cryptocurrencies. Within a few years of its appearance, it has become popular not even locally but worldwide. The method of data processing and analysis, quantitative and qualitative research methods, statistical-economic analysis methods are mainly used when working on the paper. The research aims to identify the main directions of cryptocurrency development in globalisation threats and challenges. Most cryptocurrencies are built on blockchain technology. The technology of the future is designed to securely store information, expedite transactions, reduce international transaction costs, replace cb-money with e-money and eliminate intermediary circles.
Main Points of Digital Agency Business Processes Management: Foodtech Sector Case
Authors: Omelyanenko Elena , Tirto Teofilo , Volodin Dmitry , Omelyanenko Vitaliy , Kovtun Galina
Published: November 2021

The research deals with the analytics of the features of business processes of a digital agency and the identification of promising aspects of digital marketing as a tool for B2B interaction in the Foodtech market. It is noted that the primary trend of the Foodtech sector deals with digital transformation. From the strategic point of view of creating a business model, it is necessary to understand that digital transformation involves the installation of modern hardware or software and fundamental changes in approaches to management, corporate culture, and communications. To increase the efficiency of the digital agency’s business model, the authors propose to consider digital marketing. The analysis of the effectiveness of the business model of the digital agency allowed us to identify the most problematic and, at the same time, promising components of the business model. Based on generalized approaches to business model management in the case of a digital agency in the design of relevant services, it is proposed to consider maximizing the speed and efficiency of business model transformation and minimizing the uncertainty of further digital service development based on customer relationship management.
Insolvency Law Adaptation to the Covid-19 New Challenges: the Process of Destigmatisation and the Focus on the Rehabilitation of Business
Authors: Koshcheeva Elena S. , Minnullina Kamilla A. , Folgerova Julia N.
Published: November 2021

The institution of insolvency (bankruptcy) occupies a special place in the state institutions system to support business entities in the recovery process from the crisis, given the selection mechanisms and rehabilitation opportunities inherent in it. Bankruptcy on the global economy scale serves as one of the anti-crisis regulation tools to improve financial and economic stability. The Covid-19 pandemic has actualised the ensuring the bankruptcy law institutional capacity problem by maximising its anti-crisis potential. Given its spread scale, the insolvency law adaptation to the Covid-19 new challenges is a challenge faced by all legal systems without exception. The findings of this study reveal that fragmented and uncoordinated national responses have common trends caused by the unity goal of minimising economically and financially destructive effects of the pandemic. This study objective was to identify the most effective strategy for the bankruptcy institute modernisation, which solution is based on the elements comparative analysis and convergence methods. In conclusion, the bankruptcy institute development basic tendencies and patterns have been revealed. Their analysis has allowed designating the legislation perfection most effective and perspective strategies in this sphere, which are determined by the course to aim at its anti-crisis potential development.
The Role of Cultural and Creative Industries Sector for Post-COVID Recovery
Authors: Prause Gunnar
Published: November 2021

Cultural and Creative Industries (CCIs) have been intensively studied within the last decades due to their high economic growth potential and positive impact on innovation. In recent years, research shows increasing efforts to unfold CCIs’ potential for innovation partnerships in cross-sectoral cooperation with traditional companies. This classical role of CCI has been discussed in the new context in the frame of COVID-19. Here, the CCI sector itself had to find other channels to meet their clients, but besides that, an extended role of the CCI sector for post-COVID recovery is debated by several key players, including OECD. The paper analyses the current socio-economic situation that is still shadowed by the ongoing COVID pandemic and discusses sustainable and inclusive growth paths of a post-COVID recovery driven by creativity concepts. The Baltic Sea Region (BSR) as the first macro-region with its own macro-regional strategy and its strong innovation power, domination of SME sector, low population density, its heterogeneous business structures resulting from its characteristic mixture of old and new EU Member States can be considered as a test lab for the whole Europe. From the CCI perspective, its long Hanse history that generated a common Baltic identity opens the opportunity to deploy common cultural approaches for successful inter-cultural recovery concepts.
Impact of the Covid-19 Pandemic on Entrepreneurial Capacity and Financial Security in Ukraine
Authors: Derbenova Yana , Kashyna Ganna , Leontovych Serhii , Ablova Olena , Dmitrieva Oksana , Yaremenko Lyudmyla
Published: November 2021

The article analyzes the impact of the COVID-19 pandemic on business activities in Ukraine and the world and its financial security. The analysis showed that the economy of Ukraine and most countries of the world suffered significant losses from the introduction of anti-epidemic restrictions on business activity, which turned out to be in the fall of GDP, index of industrial production investment activity. Because of temporary or complete shutdown of business the unemployment rate increased significantly. The pandemic crisis also negatively impacted the financial results of enterprises, which decreased significantly in all kinds of economic activities, especially in industry, transport, temporary accommodation and catering, where the share of unprofitable enterprises reaches 73%. Thus, the problem of ensuring the financial security of business becomes relevant. The aim of the work is to develop methodological approaches to assessing the impact of the pandemic crisis on the financial security of business and to identify effective ways of ensuring such security. In the process of research methods of scientific abstraction, comparative and system analysis and synthesis, systematization and logical generalization were used. It was determined that the pandemic affected small and medium businesses most of all, where a strong negative impact was experienced by more than 60% of entrepreneurs. Large businesses were less affected, but they also suffered significant losses due to the decline in business activity and demand in the domestic and foreign markets. Agriculture was least affected by the pandemic, which suffered the least losses, primarily due to the insignificant impact of restrictions affecting the activities of this business. The paper systematized the risks arising from the factors of the pandemic crisis, identifying their manifestations and financial implications for business. As shown by the research, such consequences are manifested in the form of full or partial loss of profits, problems with debt repayment, reduction of financial stability, liquidity, increase in accounts receivable, increased costs for anti-epidemic measures, etc. Thus, the procedure for assessing the business’s financial security is to take into account all factors that shape the financial situation of business entities during a pandemic crisis in a comprehensive manner.
Microfluidic photoreactor to treat neonatal jaundice
Authors: Lahmann John M. , Faase Ryan A. , Leu Hsuan Yu , Jacques Steven L. , Scottoline Brian , Schilke Kate F. , Baio Joe E. , Higgins Adam Z.
Published: November 2021

While in most cases, jaundice can be effectively treated using phototherapy, severe cases require exchange transfusion, a relatively risky procedure in which the neonate's bilirubin-rich blood is replaced with donor blood. Here, we examine extracorporeal blood treatment in a microfluidic photoreactor as an alternative to exchange transfusion. This new treatment approach relies on the same principle as phototherapy but leverages microfluidics to speed up bilirubin removal. Our results demonstrate that high-intensity light at 470 nm can be used to rapidly reduce bilirubin levels without causing appreciable damage to DNA in blood cells. Light at 470 nm was more effective than light at 505 nm. Studies in Gunn rats show that photoreactor treatment for 4 h significantly reduces bilirubin levels, similar to the bilirubin reduction observed for exchange transfusion and on a similar time scale. Predictions for human neonates demonstrate that this new treatment approach is expected to exceed the performance of exchange transfusion using a low blood flow rate and priming volume, which will facilitate vascular access and improve safety.
Probing microstructural differences that manifest in human blood after taking aspirin using thixo-elasto-visco-plastic modeling and series of physical processes
Authors: Armstrong Matthew , Milner Erin , Bailey Dorian , Pincot Andre , Brown Thomas , Nguyen Lam , O’Donovan Kevin , Nguyen Chi , Corrigan Trevor
Published: November 2021

Although prophylactic use of low dosage acetylsalicylic acid (aspirin) to inhibit the effects of platelet aggregation is common, a few, if any, rheological studies validating the change in the physical and mechanical properties of human blood post-aspirin administration have been reported. Recent work modeling the rheological behavior of thixo-elasto-visco-plastic materials, such as human blood, indicates that they have all the hallmark features of a complex material, including shear-thinning, viscoelasticity, yield stress, and thixotropy. Using human blood rheological data collected on a Discovery Hybrid Rheometer, before and after a 14-day protocol of once daily 81 mg aspirin tablet, we compare the mechanical properties with the recently published enhanced thixotropic modified Horner–Armstrong–Wagner–Beris thixo-elasto-visco-plastic model and sequence of physical processes. We do so to highlight the subtle shift in mechanical properties in terms of the “liquid-like” and “solid-like” nature of blood. We will show both before and after parametric analysis, profile, and comparison, as well as the before and after aspirin elastic and viscous properties of the human blood.
Uniform subwavelength high-aspect ratio nanogratings on metal-protected bulk silicon produced by laser-induced periodic surface structuring
Authors: Bronnikov Kirill , Dostovalov Alexander , Terentyev Vadim , Babin Sergey , Kozlov Aleksey , Pustovalov Eugeny , Gurevich Evgeny L. , Zhizhchenko Alexey , Kuchmizhak Aleksandr
Published: November 2021

Formation of highly ordered nanostructures on a crystalline silicon surface is highly demanded for novel optoelectronic and nanophotonic designs pushing toward development of inexpensive and high-performing nanostructuring technologies. Here, we demonstrate that laser-induced periodic surface structuring of c-Si protected by a thin Hf over-layer allows one to fabricate extremely uniform high-aspect-ratio gratings with a characteristic periodicity of ≈900–950 and 450 nm. Corresponding ordering originates from interference of incident IR femtosecond laser pulses with surface plasmons as well as doubling of the grating period via interference of counter-propagating plasmons. A high-melting-point Hf over-layer regulates the c-Si ablation in the plasmon-mediated interference maxima and prevents its excessive oxidation upon multi-pulse exposure in ambient environment. Considering unique high-aspect ratio morphology (a depth-to-period ratio of up to 1.24 and a depth-to-width ratio of up to 8) of the reported nanogratings, their outstanding uniformity, and rather fast printing rate of ≈0.2 mm2/s as well as possibility for its further upscaling, we envision high practical applicability of this technology in novel optoelectronic devices, visible and near-IR optics, all-dielectric metasurfaces, and sensors.
Wrestling with Light
Authors: Dakin James T.
Published: November 2021

This book presents a chronology of the science and technology of light and focuses on the phenomena and joy of discovery rather than mathematical theories and derivations. The book presents an easy-to-read guide to the integration of science and engineering, and combines it with the history of discoveries, inventions, and applications involving light phenomena.

Wrestling with Light: History, Science and Applications features:A chronological approach to the study of lightThe combination of scientific principles and commercial product developmentInteresting historical details about the disruption of the lighting industry caused by globalization and changes in technology

Researchers, graduate, and undergraduate students in optics and physics will find this an inspiring resource. Those fascinated by light or professionals considering careers related to light will find this an interesting overview.
Electromagnetism, Quanta, and Materials
Authors: Dakin James T.
Published: November 2021

Mysteries of the late 19th century were mostly resolved as the science of light was consolidated by around 1930. Key developments were Maxwell's equations, Planck's introduction of quanta to explain blackbody radiation, Einstein's associating these quanta with light to explain the photoelectric effect, and the contributions of many to develop quantum mechanics to explain the structures of atoms, molecules, and solids. Few questions of a basic scientific nature remained. Out of the new science emerged critical advances such as the p-n junction, the laser, and new materials to manipulate light. Light could be both a particle and a wave at the same time.
QED, Quarks, and the Standard Model
Authors: Dakin James T.
Published: November 2021

The photon of light plays a central role in the standard model of elementary particles, both as a tool in establishing the model and as its charter member. The field of elementary particle physics grew in the mid-20th century, and blossomed in the late 20th century. By then it was understood that, at the most basic level, the forces between charged particles could best be explained with quantum electrodynamics, in which the photon, not an electric field, transmits force. The photon of light played a central role in key experiments at the Stanford Linear Accelerator Center (SLAC), which solidified the existence of quarks as basic nuclear constituents. In the standard model, which grew out of this work, the photon is the charter member.
Reflections
Authors: Dakin James T.
Published: November 2021

A review of the earlier chapters brings several interesting themes to light, most of which are broader than light. First is the relationship between basic scientific understanding and practical application. Second is the multidisciplinary character of most applications, with the special importance of materials and manufacturing processes. Third is the important role of religion in the early development of science. Fourth is the question of whether an advance can be attributed to an individual celebrity, or to a collective effort. Fifth is a revisiting of the premise that the broad, deep story of light cannot be found in any single book or university course. Sixth is reflection on the absence of women in the history of light and science in general.
Invasive Japanese foraminifera in a south-west Australian estuary
Authors: Tremblin Clément M. , Holzmann Maria , Parker Justin H. , Sadekov Aleksey , Haig David W.
Published: November 2021

An invasive foraminiferan is recorded for the first time in an Australian estuary. Trochammina hadai, originally described as endemic from Japan and subsequently found to be alien in coastal waters of California and Brazil, has been identified in estuarine sediment in the vicinity of Bunbury Port in Western Australia. Species determination is based on morphological, molecular and ecological similarities to the Japanese type. The species has not been recorded in other estuaries in Australia. Bunbury Port is a major exporter of woodchip to Japan and the introduction of T. hadai may have come from ballast water out of shallow-draught woodchip vessels. Small sediment samples of estuarine mud obtained at water depths of ~5 m contain abundant T. hadai (on average ~0.4 mm in adult diameter) that are easily recognised in microscopic view of the sediment surface by their bright reddish-brown colour. The collection of sediment samples from the estuarine floor and ballast water, and the examination of these for foraminifers, may provide a useful indicator in estuaries for the possible presence of other exotic species, particularly in the vicinity of ports.
Distributional conformal prediction
Authors: Chernozhukov Victor , Wüthrich Kaspar , Zhu Yinchu
Published: November 2021

Significance

Prediction problems are important in many contexts. Examples include cross-sectional prediction, time series forecasting, counterfactual prediction and synthetic controls, and individual treatment effect prediction. We develop a prediction method that works in conjunction with many powerful classical methods (e.g., conventional quantile regression) as well as modern high-dimensional methods for estimating conditional distributions (e.g., quantile neural networks). Unlike many existing prediction approaches, our method is valid conditional on the observed predictors and efficient under some conditions. Importantly, our method is also robust; it exhibits unconditional coverage guarantees under model misspecification, under overfitting, and with time series data.
Nonlinear nanoelectrodynamics of a Weyl metal
Authors: Shao Yinming , Jing Ran , Chae Sang Hoon , Wang Chong , Sun Zhiyuan , Emmanouilidou Eve , Xu Suheng , Halbertal Dorri , Li Baichang , Rajendran Anjaly , Ruta Francesco L. , Xiong Lin , Dong Yinan , McLeod Alexander S. , Sunku Sai S. , Hone James C. , Moore Joel , Orenstein Joe , Analytis James G. , Millis Andrew J. , Ni Ni , Xiao Di , Basov D. N.
Published: November 2021

Significance

Nonlinear optics in topological semimetals is a burgeoning field of research with an expanding list of new materials but limited choice of probes. We devised, modeled, and implemented an approach for investigating nonlinear optics at the nanoscale with a metallic tip. Far-field nonlinear optics are diffraction-limited and probe the in-plane response only. Our tip-based approach circumvents the diffraction limit and provides strong field enhancement for both in-plane and out-of-plane fields. We therefore gain access to complete nonlinear tensors including components not attainable before. One immediate application of our approach is the separation of surface state and bulk nonlinear responses in Weyl semimetals. Applying near-field probes to topological semimetals constitutes a new paradigm of research on nanoscale nonlinearity.
Linguistic territoriality in Switzerland
Authors: Burckhardt Till
Published: November 2021

This article argues that the linguistic territoriality principle cannot be considered as a general guideline for the design of language policy but rather as a tool to find the right balance between linguistic freedom and linguistic peace under given circumstances. The article traces the origin and evolution of language policy principles during the drafting process of the new constitutional article in its three official language versions. The Swiss language regime is embedded in an institutional system of executive federalism in which mostly monolingual cantons and municipalities are in charge of implementing nearly all public policy. This significantly reduces the relevance of the inconsistency between a formally personalistic multilingual federal language regime and linguistic territoriality deriving from cantonal language regimes. The point of the new federal regulation is to provide room for manoeuvre for cantonal policymakers to adopt legislation based on linguistic territoriality. The relevant constitutional article recognises that territorial language policies can be implemented to ensure linguistic peace. At the same time, the personality principle may be adopted to protect autochthonous linguistic minorities.
Dynamic compression behaviour and microstructure of ZK60 alloy under different strain rates
Authors: Wang Zhi , Huang Shouben , Wang Feng , Zhou Le , Tie Di , Mao Pingli , Liu Zheng
Published: November 2021

In this study, the split Hopkinson pressure bar was used to investigate the effect of ageing treatment on dynamic compression properties and microstructure of extruded ZK60 alloy under different strain rates. The experimental results demonstrated that the amount of the precipitated MgZn and MgZn2 phases increases after ageing treatment. The peak flow stress increases with increasing strain rate. Due to ageing precipitation strengthening, the dynamic compressive strength of the ZK60 alloy is improved. EBSD and TEM results indicated that the dynamic compression deformation mechanism of the ZK60 alloy is the interaction of twins, dislocations, and dynamic recrystallisation. Furthermore, the extension twinning boundaries and the precipitated phases hinder the slip of dislocations during deformation, which significantly affects dislocation strengthening.
Reconstitution of human atlastin fusion activity reveals autoinhibition by the C terminus
Authors: Crosby Daniel , Mikolaj Melissa R. , Nyenhuis Sarah B. , Bryce Samantha , Hinshaw Jenny E. , Lee Tina H.
Published: November 2021

ER network formation depends on membrane fusion by the atlastin (ATL) GTPase. In humans, three paralogs are differentially expressed with divergent N- and C-terminal extensions, but their respective roles remain unknown. This is partly because, unlike Drosophila ATL, the fusion activity of human ATLs has not been reconstituted. Here, we report successful reconstitution of fusion activity by the human ATLs. Unexpectedly, the major splice isoforms of ATL1 and ATL2 are each autoinhibited, albeit to differing degrees. For the more strongly inhibited ATL2, autoinhibition mapped to a C-terminal α-helix is predicted to be continuous with an amphipathic helix required for fusion. Charge reversal of residues in the inhibitory domain strongly activated its fusion activity, and overexpression of this disinhibited version caused ER collapse. Neurons express an ATL2 splice isoform whose sequence differs in the inhibitory domain, and this form showed full fusion activity. These findings reveal autoinhibition and alternate splicing as regulators of atlastin-mediated ER fusion.
Review of the thermoelectric properties of layered oxides and chalcogenides
Authors: Romanenko A I , Chebanova G E , Chen Tingting , Su Wenbin , Wang Hongchao
Published: November 2021

The current state of investigation on thermoelectric properties of layered chalcogenides and oxides is considered. The relationship between the quasi-two-dimensionality of electronic transport properties and thermoelectric properties is confirmed. A decrease in the dimension of electron transport from three-dimensional to quasi-two-dimensional in materials with a layered structure increases the thermopower with a slight change in electrical conductivity. The bismuth tellurides, bismuth selenides and its alloys are currently one of the outstanding state of the art bulk thermoelectric materials with layered structure. Layered transition metal dichalcogenides MX2 (M is a transition metal, X is a chalcogen) are efficient thermoelectric materials at higher temperatures (500–800 K). In these materials, an increase in thermoelectric properties associated with the two-dimensionalization of electron transport is also observed. Layered monochalcogenides MX (M = Sn, Pb, Ge; X = S, Se, Te) are also a promising class of thermoelectric materials. In SnSe single crystals,

Z
T
∼
2.6

is obtained at 923 K due to the very low thermal conductivity along the b axis (0.23 W (m K)−1 at 973 K). Layered chalcogenides CuCrX2 (X = S, Se, Te) containing magnetic Cr atoms are effective thermoelectrics at higher temperatures (up to 800 K) due to the presence of phonon glass–electron crystal state led to a significant decrease in thermal conductivity at high temperatures. Magnetic atoms in CuCrX2 compounds lead to the presence of magnetic phase transitions affecting their thermoelectric properties. Interest in oxide-based thermoelectric materials has significantly increased due to their stability in air and higher temperatures for maximum efficiency. The most promising thermoelectric oxide materials Ca3Co4O9, Na
x
CoO2, Bi2Ca2Co2O
x
, and CaCo2O4 have a layered structure and contain magnetic Co atoms leading to magnetic ordering and influence on thermoelectric properties. The presence of phase transitions affects the thermoelectric parameters of thermoelectrics and the thermoelectric figure of merit ZT.
Exploring metastable states in UO2 using hybrid functionals and dynamical mean field theory
Authors: Ratcliff Laura E , Genovese Luigi , Park Hyowon , Littlewood Peter B , Lopez-Bezanilla Alejandro
Published: November 2021

A detailed exploration of the f-atomic orbital occupancy space for UO2 is performed using a first principles approach based on density functional theory (DFT), employing a full hybrid functional within a systematic basis set. Specifically, the PBE0 functional is combined with an occupancy biasing scheme implemented in a wavelet-based algorithm which is adapted to large supercells. The results are compared with previous DFT + U calculations reported in the literature, while dynamical mean field theory is also performed to provide a further base for comparison. This work shows that the computational complexity of the energy landscape of a correlated f-electron oxide is much richer than has previously been demonstrated. The resulting calculations provide evidence of the existence of multiple previously unexplored metastable electronic states of UO2, including those with energies which are lower than previously reported ground states.
An adaptive multiple time domain synchronous averaging method and its application in vibration signal feature enhancement
Authors: Yin Na , Meng Zong , Guan Yang , Fan Fengjie
Published: November 2021

The time domain synchronous averaging (TSA) method is a typical time domain signal denoising method, which is widely used in the state detection of rotating machinery. In order to solve the difficult problem of extracting vibration signal features from strong interference, an adaptive multiple time domain synchronous averaging method based on signal period is proposed in this paper. In view of the blindness and randomness of period selection in the TSA method, a new evaluation index of periodic impulse characteristics is proposed. In this method, the signal is resampled then the iteration stop threshold is set, and then the calculation period of interest is determined by two cycle screening. Finally, reconstructed signals with enhanced features are obtained by copying and stitching. Experimental results show that the proposed method is robust and superior in the feature detection of rolling bearing vibration signals.
Medical image segmentation with generative adversarial semi-supervised network
Authors: Li Chuchen , Liu Huafeng
Published: November 2021

Recent medical image segmentation methods heavily rely on large-scale training data and high-quality annotations. However, these resources are hard to obtain due to the limitation of medical images and professional annotators. How to utilize limited annotations and maintain the performance is an essential yet challenging problem. In this paper, we try to tackle this problem in a self-learning manner by proposing a generative adversarial semi-supervised network. We use limited annotated images as main supervision signals, and the unlabeled images are manipulated as extra auxiliary information to improve the performance. More specifically, we modulate a segmentation network as a generator to produce pseudo labels for unlabeled images. To make the generator robust, we train an uncertainty discriminator with generative adversarial learning to determine the reliability of the pseudo labels. To further ensure dependability, we apply feature mapping loss to obtain statistic distribution consistency between the generated labels and the real labels. Then the verified pseudo labels are used to optimize the generator in a self-learning manner. We validate the effectiveness of the proposed method on right ventricle dataset, Sunnybrook dataset, STACOM, ISIC dataset, and Kaggle lung dataset. We obtain 0.8402–0.9121, 0.8103–0.9094, 0.9435–0.9724, 0.8635–0.886, and 0.9697–0.9885 dice coefficient with 1/8 to 1/2 proportion of densely annotated labels, respectively. The improvements are up to 28.6 points higher than the corresponding fully supervised baseline.
Ion transit effects on sheath dynamics in the intermediate radio-frequency regime: excitations of ion-acoustic waves and solitons
Authors: Shihab M , Elbadawy A , El-Siragy N M , Afify M S
Published: November 2021

Capacitively coupled plasma is investigated kinetically utilizing the particle-in-cell technique. The argon (Ar) plasma is generated via two radio frequencies. The plasma bulk density increases by increasing the voltage amplitude of the high frequency (⩾13.56 MHz), which is much greater than the ion plasma frequency. The intermediate radio frequencies (≈1 MHz), which are comparable to the ion plasma frequency, cause a considerable broadening of the ion energy distribution, i.e. ions gain energies higher and lower than the time-averaged energy. The good agreement between published experimental results and our theoretical calculations via the ensemble-in-spacetime model confirms the modulation of ions around time-averaged values. Intermediate frequencies allow ions to partially respond to the instantaneous electric field. The response of ions to the instantaneous electric field is investigated semi-analytically. The dispersion relation of the plasma sheath and bulk are derived. Stable ion acoustic modes are found. Ion-acoustic modes have two different velocities and carry energy from the sheath edge to the electrode. In addition, intermediate frequencies excite solitons in the plasma sheath. The results may help to explain the ion density, flux, and energy modulation, and, consequently, the broadening of the ion energy distribution.
Quantum simulation of molecules without fermionic encoding of the wave function
Authors: Mazziotti David A , Smart Scott E , Mazziotti Alexander R
Published: November 2021

Molecular simulations generally require fermionic encoding in which fermion statistics are encoded into the qubit representation of the wave function. Recent calculations suggest that fermionic encoding of the wave function can be bypassed, leading to more efficient quantum computations. Here we show that the two-electron reduced density matrix (2-RDM) can be expressed as a unique functional of the unencoded N-qubit-particle wave function without approximation, and hence, the energy can be expressed as a functional of the 2-RDM without fermionic encoding of the wave function. In contrast to current hardware-efficient methods, the derived functional has a unique, one-to-one (and onto) mapping between the qubit-particle wave functions and 2-RDMs, which avoids the over-parametrization that can lead to optimization difficulties such as barren plateaus. An application to computing the ground-state energy and 2-RDM of H4 is presented.
Actively Q-switched Nd:YLF laser emitting at 908 nm
Authors: Zhang Jiale , Ma Jian , Lu Tingting , Zhu Xiaolei
Published: November 2021

An actively Q-switched quasi-three-level Nd:YLF laser emitting at 908 nm, for the first time to our knowledge, was demonstrated. A RTP double-crystal scheme was used to realize electro-optical Q-switcher, and a L-shaped cavity structure was designed to suppress parasitic oscillation at 1047 nm. An 806 nm laser diode was used as the pump source with about 480 μs pulse width. With 46.4 mJ pump pulse energy input at repetition rate of 100 Hz, maximum output pulse energies of 0.84 mJ and 0.73 mJ were obtained with output transmissions of 6.5% and 11%, respectively. The corresponding peak pulse powers were up to 14.3 kW and 12.1 kW, and the output pulse widths were 58.6 ns and 60.3 ns. The central laser wavelengths were both at 908.3 nm with spectral bandwidth of over 0.7 nm.
Thermodynamic effects of Bardeen black hole surrounded by perfect fluid dark matter under general uncertainty principle
Authors: Nie Zhenxiong , Liu Yun , Chen Juhua , Wang Yongjiu
Published: November 2021

The thermodynamics of Bardeen black hole surrounded by perfect fluid dark matter is investigated. We calculate the analytical expresses of corresponding thermodynamic variables, e.g., the Hawking temperature, entropy of the black hole. In addition, we derive the heat capacity to analyze the thermal stability of the black hole. We also compute the rate of emission in terms of photons through tunneling. By numerical method, an obvious phase transition behavior is found. Furthermore, according to the general uncertainty principle, we study the quantum corrections to these thermodynamic quantities and obtain the quantum-corrected entropy containing the logarithmic term. Lastly, we investigate the effects of the magnetic charge g, the dark matter parameter k and the generalized uncertainty principle parameter α on the thermodynamics of Bardeen black hole surrounded by perfect fluid dark matter under general uncertainty principle.
FPGA implementation and image encryption application of a new PRNG based on a memristive Hopfield neural network with a special activation gradient
Authors: Yu Fei , Zhang Zinan , Shen Hui , Huang Yuanyuan , Cai Shuo , Du Sichun
Published: November 2021

A memristive Hopfield neural network (MHNN) with a special activation gradient is proposed by adding a suitable memristor to the Hopfield neural network (HNN) with a special activation gradient. The MHNN is simulated and dynamically analyzed, and implemented on FPGA. Then, a new pseudo-random number generator (PRNG) based on MHNN is proposed. The post-processing unit of the PRNG is composed of nonlinear post-processor and XOR calculator, which effectively ensures the randomness of PRNG. The experiments in this paper comply with the IEEE 754-1985 high precision 32-bit floating point standard and are done on the Vivado design tool using a Xilinx XC7Z020CLG400-2 FPGA chip and the Verilog-HDL hardware programming language. The random sequence generated by the PRNG proposed in this paper has passed the NIST SP800-22 test suite and security analysis, proving its randomness and high performance. Finally, an image encryption system based on PRNG is proposed and implemented on FPGA, which proves the value of the image encryption system in the field of data encryption connected to the Internet of Things (IoT).
Nonlinear burn control in ITER using adaptive allocation of actuators with uncertain dynamics
Authors: Graber V. , Schuster E.
Published: November 2021

ITER will be the first tokamak to sustain a fusion-producing, or burning, plasma. If the plasma temperature were to inadvertently rise in this burning regime, the positive correlation between temperature and the fusion reaction rate would establish a destabilizing positive feedback loop. Careful regulation of the plasma’s temperature and density, or burn control, is required to prevent these potentially reactor-damaging thermal excursions, neutralize disturbances and improve performance. In this work, a Lyapunov-based burn controller is designed using a full zero-dimensional nonlinear model. An adaptive estimator manages destabilizing uncertainties in the plasma confinement properties and the particle recycling conditions (caused by plasma–wall interactions). The controller regulates the plasma density with requests for deuterium and tritium particle injections. In ITER-like plasmas, the fusion-born alpha particles will primarily heat the plasma electrons, resulting in different electron and ion temperatures in the core. By considering separate response models for the electron and ion energies, the proposed controller can independently regulate the electron and ion temperatures by requesting that different amounts of auxiliary power be delivered to the electrons and ions. These two commands for a specific control effort (electron and ion heating) are sent to an actuator allocation module that optimally maps them to the heating actuators available to ITER: an electron cyclotron heating system (20 MW), an ion cyclotron heating system (20 MW), and two neutral beam injectors (16.5 MW each). Two different actuator allocators are presented in this work. The first actuator allocator finds the optimal mapping by solving a convex quadratic program that includes actuator saturation and rate limits. It is nonadaptive and assumes that the mapping between the commanded control efforts and the allocated actuators (i.e. the effector model) contains no uncertainties. The second actuator allocation module has an adaptive estimator to handle uncertainties in the effector model. This uncertainty includes actuator efficiencies, the fractions of neutral beam heating that are deposited into the plasma electrons and ions, and the tritium concentration of the fueling pellets. Furthermore, the adaptive allocator considers actuator dynamics (actuation lag) that contain uncertainty. This adaptive allocation algorithm is more computationally efficient than the aforementioned nonadaptive allocator because it is computed using dynamic update laws so that finding the solution to a static optimization problem is not required at every time step. A simulation study assesses the performance of the proposed adaptive burn controller augmented with each of the actuator allocation modules.
Intensification of heat exchange by an ultrasound source for milk pasteurization.
Authors: Biryukov D A , Mironov I S , Shvydkya A V
Published: November 2021

The goal of this article is to investigate the effect of ultrasonic vibrations on the process of milk pasteurization. Ultrasound can potentially intensify heat transfer and reduce the formation of thermal sediment (soot deposit) on the walls of heat-exchange devices. The paper presents the results of experimental studies demonstrating the growth rate of thermal sediment on the wall of the heat-exchange apparatus and its amount in the volume of milk under the influence of ultrasonic vibrations and without it.
Investigation of water-air flows in nozzles
Authors: Chernykh A A , Sharapov A I , Arzamastsev A G , Shatskikh Y V
Published: November 2021

The undoubted importance of these problems allows us to conclude that the research aimed at creating and using a simple model of the flow of a two-phase medium is relevant and of interest not only from a scientific, but also from a practical point of view. Two approaches to their description can be distinguished: the study of flows of two-phase media taking into account relaxation processes between phases with a microscopic description of the interaction between phases, or the study of flows of two-phase media with a macroscopic description of the medium in the form of a one-speed one-temperature continuum. However, sometimes, when calculating, it is possible to ignore the structural two-phase medium and consider the medium as a one-speed one-temperature continuum. This proposal allows us to calculate the averaged flow parameters of a two-phase medium, which is required for engineering calculations. In this paper, the calculation of the flow of the gas-drop flow in the Laval nozzle is given. The method is described, which is based on integral energy equations for two-phase dispersed currents. In the calculations, the two-phase flow is considered as a single-speed, single-temperature continuum. When modeling in the ANSYS Fluent software package, a package of Euler equations is used to compare with analytical results obtained from integral energy equations.