bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal Detection for Free Flight
Authors: Tallman Jake , Yu David , Pantoja Maria
Published: March 2021

Thermals are regions of rising hot air formed on the ground through the warming of the surface by the sun. Thermals are commonly used by birds and glider pilots to extend flight duration, increase cross-country distance, or simply to conserve energy. This kind of powerless flight using natural sources of lift is called soaring. Once a thermal is encountered, the pilot flies in circles to keep within the thermal, so gaining altitude before flying off to the next thermal and towards the destination. A single thermal can net a pilot thousands of meters of elevation gain. Estimating thermal locations is not an easy task, pilots look for different indicators like color variation on the ground because the difference in the amount of heat absorbed by the ground varies based on the color/composition, birds circling in an area, and certain types of cloud formations (cumulus clouds). The above methods are not always reliable enough and pilots study the conditions for thermals by estimating solar heating of ground (cloud cover and time year/date) and also the lapse rate and dew point of air. In this paper, we present a Machine Learning based solution to forecast thermals. Since pilots in general record many of their flights locally and sometimes upload them to databases, we use the flight data uploaded to determine where the pilot encountered thermals and together with other information (weather and satellite images corresponding to the location and time of the flight) train an algorithm to automatically predict the location of thermals given as input the current weather conditions and terrain information (obtained from Google Earth Engine). Results show that our model is able to converge on the training and validation set with a loss bellow 1%.
Educational Gaps in Latin American childhood: Regional Inequality in Learning Deprivation with Local Modulations
Authors: Sánchez-Restrepo Harvey , Louçã Jorge
Published: March 2021

This research is a secondary analysis of a multivariate dataset coming from a large-scale assessment, coordinated by UNESCO in 15 Latin American countries (LAC), which was carried out for estimating the level of learning achievements of students at the end of primary education. The objective is to estimate the lack of quality in education across the region, based on the sociological concepts of absolute and relative deprivation, through a new learning deprivation index, as well as to offer robust evidence on the deep inequalities in learning outcomes among groups of population. Main results show strong evidences on how big gaps in learning outcomes are associated with socioeconomic status of students, pointing out that the profound lack of equity in LAC has become structural inequality beyond borders. This study establishes three milestones in educational research using the best available data. First, provides a direct method for estimating learning deprivation. Second, intra-and inter-country inequality is estimated from comparable socioeconomic deciles at regional level. Third, it was found that the intensity of learning deprivation, as a function of the SES, has an interplay with the wealth of the country and it is not possible to apply same strategies in all countries for developing inclusive and equitable educational for all.
Two Degree-of-freedom μ Synthesis Control for Turbofan Engine with Slow Actuator Dynamics and Uncertainties
Authors: Zhu Meiyin , Wang Xi , Miao Keqiang , Pei Xitong , Liu Jiashuai
Published: March 2021

To address the robust control problem of turbofan engine with slow actuator dynamics and uncertainties, we present a two degree-of-freedom (TDOF) μ synthesis control scheme. The actuators with slow dynamics and parameter uncertainties are considered in the control design. To handle the problem of rapid change of reference command, feed forward control (one freedom) is adopted, and feedback control (another freedom) is introduced to ensure good servo tracking and disturbance attenuation. The performance and the control output weighting functions are properly devised to guarantee servo tracking and disturbance attenuation performance of the devised controller. The D-K iterative algorithm is adopted to calculate the TDOF μ synthesis controller. A turbofan engine with slow actuator dynamics and parameter uncertainties is adopted for simulation. The effectiveness and superiority of the devised TDOF μ synthesis controller are verified by a series of simulation analyses. The simulation analyses show that the TDOF μ synthesis control scheme developed in this paper can handle the robust control problem of turbofan engines, despite the negative influence of the slow actuator dynamics and uncertainties. The comparison shows that the TDOF μ synthesis controller provides better performance than the PI controller and the LMI optimization gain scheduled controller do.
Two-Timescale Missile Autopilot Design Based on Suboptimal Control
Authors: Li Zongxing , Zhang Rui
Published: March 2021

Aiming at the missile longitudinal motion model with obvious aerodynamic nonlinearity, this paper proposes a two-timescale design method of missile autopilot based on suboptimal control. By dividing the system states into fast and slow states based on different timescales, the corresponding fast and slow control inputs are designed. This paper introduces suboptimal control and robust control to enable the system to have good dynamic response characteristics, and the system’s ability to suppress various uncertainties is guaranteed. By applying the Lyapunov method, the stability conditions of the system are given. Finally, the simulation results show that the system has good dynamic characteristics and robustness.
Research and Engineering Implementation of Laser Point Cloud 3D Target Recognition Algorithm in Complex Scene
Authors: Shi Shixi , Zhou Yifu , Sun Yang , Ding Ziquan , Hou Xiaoxiang , Li Tao , Cao Jihong , Tan Yijun , Deng Bu , Li Hongyi , Zhang Jun , Gu Yaping
Published: March 2021

Here are many challenges for target detection in the complex scenes. In the real scene, such as the diversity of the type, quantity and shape of the parts on the workpiece plates, the model construction and rapid detection need to deal with the complex and changeable scene, and the large-scale massive point cloud data challenges the operational efficiency and accuracy of visibility analysis technology. In this paper, the 3D modeling method based on computer graphics is proposed by using the displacement laser sensor as the digital representation of 3D complex scene on the scanning point cloud, which realizes the fast extraction of semantic target feature parameters under complex conditions. The multi-dimensional parameter-based saliency feature and fusion multiple filtering algorithm is built to obtain a fast and high-precision intelligent template recognition detection method. Based on SOC embedded engineering technology, the detection algorithm is realized by software programming. The two-dimensional mechanical motion platform is developed to test the workpiece plate applied to wheel hub of high-speed rail train, and the recognition accuracy is more than 99%.
Iterative PSO Algorithms for RAP Problems with k-out-of-n:G Subsystems and Mixing of Components and Changing k Values
Authors: Li Dongkui , Wulantuya  , Zhu Yanlong , Li Xuebao , Yang Liiping , Xia Yuqin
Published: March 2021

The subsystem is k-out-of-n: G configuration, and the subsystem has component mixing (that is, subsystem components can be selected from different kinds of components), and the minimum number of normal working elements (k value) that can be selected as well as can change RAP problem. On the basis of giving a solution construction method and generating a new solution by symmetric bit transformation technology, an iterative DPSO (discrete particle swarm optimization) algorithm with fixed-compression coefficient and dynamic inertia weight is designed to solve the model. The calculate results indicate that the algorithm can effectively give the optimal solution for each test case (which is consistent with the existing optimal results in the literature). PSO algorithm can effectively solve the RAP problem of subsystems with mixed components and varyingkvalues. When the size of subsystems (k-out-of-n: G) is large, and the solution of the model is limited by microcomputers.
Prediction and Optimization of Full-Vehicle Road Noise Based on Random Response Analysis
Authors: Cao Cheng , Meng Dejian , Zhao Ye , Shu Yuan , Zhang Menghao , Zhang Lijun
Published: March 2021

Based on the theory of random response analysis, a road noise prediction method is proposed. A finite element model of acoustic-structure coupling for the full-vehicle was established, and the road surface texture measured in the actual vehicle test was converted into a power spectrum, which is the excitation of FE model. Under the conditions of coast down from 80km/h to 20km/h on Belgian pavement, the prediction of road noise in the 20- 200Hz frequency band was achieved. The driver’s ear sound pressure obtained from the simulation is in good agreement with the test results, which verifies the effectiveness of the simulation model and prediction method. The sensitivity of the driver’s ear-side sound pressure level to the stiffness of the suspension mounts was further analysed. The stiffness of the bushings that had a large impact was determined. The Response Surface Methodology was used to optimize road noise. The results show that the average sound pressure level near the driver’s ear is reduced by 1.81 dBA. The simulation analysis and optimization methods introduced in this paper can provide a reference for the virtual development process of vehicle road noise.
Variable Parameter and Real-time Co-simulation Method and Its Application in the Analysis of Train Dynamic Air Consumption Law
Authors: Zuo Jianyong , Huang Shuling
Published: March 2021

System simulation technology is currently the mainstream technology for system design optimization. Parametric design can greatly improve the speed of model generation and modification by establishing various constraint relations. In this paper, the parameter design method is improved and combined with the system simulation technology, and the variable parameter and real-time co-simulation method is proposed. In order to verify the feasibility of the method in system dynamic performance analysis, this paper builds a real-time co-simulation platform based on AMESim, and applies it to the analysis process of train dynamic air consumption law. The results prove that the method is beneficial to reduce the workload of designers, and can be applied to the design optimization, analysis and tracking of complex systems.
Gamification for climate change engagement: review of corpus and future agenda
Authors: Fernández Galeote Daniel , Rajanen Mikko , Rajanen Dorina , Legaki Nikoletta-Zampeta , Langley David J , Hamari Juho
Published: March 2021

Both bottom-up and top-down initiatives are essential for addressing climate change effectively. These include initiatives aiming to achieve widespread behavioral change towards reduction of greenhouse gas emissions as well as pursuing education regarding adaptation measures. While awareness of the issue of climate change is now pervasive, and actions are being taken at all levels of society, there is still much to do if international goals are to be met. Games and gamification offer one approach to foster both behavioral change and education. In this paper, we investigate the state-of-the-art of game-based climate change engagement through a systematic literature review of 64 research outputs comprising 56 different gamified approaches. Our analysis of the literature reveals a trend of promising findings in this nascent and growing area of research, suggesting the potential to impact multiple engagement dimensions simultaneously, as well as create an engaging gameful experience. Overall, the corpus appears to offer a fruitful balance in foci between climate science, mitigation, and adaptation, as well as a variety of formats in game-based approaches (i.e. digital, analog, and hybrid). However, shortcomings were also observed, such as geographic and demographic imbalances and the short duration of interventions. The reviewed studies yield a large number of results indicating climate change engagement through gamification, especially in the form of cognitive engagement, affect towards climate change-related topics, and in-game behavioral engagement with others. Nevertheless, heterogeneity in terms of contexts, designs, outcomes, and methods, as well as limited rigor in research designs and reporting, hinders drawing overall conclusions. Based on our review, we provide guidelines regarding contexts, interventions, results, and research quality and internal validity for advancing the space of game-based interventions for climate change engagement.
Near lightcone thermal conformal correlators and holography
Authors: Parnachev Andrei
Published: March 2021

Heavy–heavy–light–light (HHLL) correlators of pairwise identical scalars in CFTs with a large central charge in any number of dimensions admit a double scaling limit where the ratio of the heavy conformal dimension to the central charge becomes large as the separation between the light operators becomes null. In this limit the stress tensor sector of a generic HHLL correlator receives contributions from the multi stress tensor operators with any number of stress tensors, as long as their twist is not increased by index contractions. We show how one can compute this leading twist stress tensor sector when the conformal dimension of the light operators is large and the stress tensor sector approximates the thermal CFT correlator. In this regime the value of the correlator is related to the length of the spacelike geodesic which approaches the boundary of the dual asymptotically AdS spacetime at the points of light operator insertions. We provide a detailed description of the infinite volume limit. In two spacetime dimensions the HHLL Virasoro vacuum block is reproduced, while in four spacetime dimensions the result is written in terms of elliptic integrals.
Study on Rule of Heavy Metal Cu2+ in Small and Medium-Sized Tailings Ponds under Rainfall-Evaporation-Transpiration Coupling
Authors: Chen Hongdan , Hao Zhe , Zhang Ying , Teng Da , Wang Xiaoming , Zhang Qian
Published: March 2021

In order to research the heavy metal migration rule of small and medium-sized tailings ponds under the action of climate, vegetation and groundwater, this paper consider the rainfall-evaporation-transpiration and coupling effect of groundwater, establish the model of different dam height, slope ratio, permeability coefficient and migration time impact on the migration of heavy metals of tailings dam, applied to Geostudio software, based on the orthogonal design method of factors significant difference analysis and design method of the comprehensive factors analysis, make up the simulation of the tailings heavy metal pollutants concentration of Cu2+ migration law. The results show that the height of tailing dam is inversely proportional to the average migration velocity of pollutant Cu2+. The effect of slope ratio on migration concentration of Cu2+ pollutant in tailings pond is not significant. The permeability coefficient has a highly significant influence on the migration of heavy metal Cu2+. At the same depth of tailings pond, when Cu2+ migrated for 365 days, the permeability coefficient increased with the increase of pollutant Cu2+ concentration. The concentration of heavy metal increased with the increase of migration time.
Study on the Effect of Chemical Conditioning on the Consolidation Characteristics of Municipal Sludge in Landfill Depot
Authors: Zhan Xinjie , Li Wenwei , Xu Xiaolong , Zhu Qunfeng
Published: March 2021

Vacuum preloading is one of the effective methods for in-situ dewatering and reduction treatment of municipal sludge landfill, but because the consolidation coefficient of municipal sludge is 1 or 2 orders of magnitude smaller than that of sludge, the drainage consolidation technology will face the problem of vacuum for too long. In order to improve the consolidation characteristics of sludge, combined with the chemical conditioning technology in the field of water treatment, firstly, the chemical conditioner suitable for landfill sludge was selected. The effects of different conditioning combinations on sludge dewatering characteristics were studied by microscopic testing techniques (zeta potential analysis and environmental scanning electron microscope analysis) and vacuum filtration test and consolidation test. The results show that the combination of ferric chloride and calcium oxide can significantly improve the dewatering characteristics of sludge. After conditioning with 10% ferric chloride and 10% calcium oxide (relative to sludge dry base), the specific resistance of sludge is reduced from 2 × 1013m/kg to 3 × 1012m / kg, and the consolidation coefficient is 3.5-10 times higher than that of original sludge, which lays a foundation for improving the efficiency of vacuum preloading treatment. In addition, from the results of vacuum filtration test and consolidation test of sludge, it can be found that there is a good negative linear relationship between specific resistance and consolidation coefficient of sludge. Compared with the consolidation test, the vacuum filtration test is simple and easy, so it can be used as an effective means to select sludge conditioner or test the conditioning effect.
Assessment of Heavy Metals in Sediments of Different Functional Areas along the Yangzong Lake Coast, Yunnan Province
Authors: Li Yanli , Fan Fu , Li Jin , Ying Xi
Published: March 2021

Contents of Cu, Zn, Ni, Cr, Fe, Mn, V, Mo, Co, Sr, Li, Be, Cd, As, Pb, Al, Ba and Ti in 40 coast sediment samples collected from the industrial, tourism and agriculture area adjacent to Yangzong Lake Coast were analyzed. Enrichment coefficient method and potential ecological risk index method have been adopted to evaluate heavy metal pollution and ecological risk. The results showed that pollution degree of Cu, Zn, Ni, Cr, Mn, Co, V from high to low was as follows: agriculture area > tourism area > industrial area. The enrichment performance of Be, As, Cd, Al, Ti, Li, Fe from high to low was as follows: agriculture area>industrial area>tourism area. The pollution degree of Mo, Pb, Sr from high to low was as follows: industrial area > tourism area > agriculture area. The pollution degree of Ba from high to low was as follows: tourism area > industrial area > agriculture area. According to the potential ecological risk coefficients, Cd, As, Cu, Co were the most hazardous elements in industrial area, tourism area and agriculture area. The request potential ecological risk index indicated that industrial area and tourism area were low-moderate potentical ecological risk, agriculture area was moderate-considerable potentical ecological risk.
Temporal and Spatial Distribution Characteristics of Precipitation over Guangzhou, China
Authors: Chen Guangxin , Chen Kui , Yang Kai , Guo Qinghao
Published: March 2021

The current study probed the spatial distribution and temporal variation of precipitation extremes over the Pearl River Delta region (PRD) depended on meteorological observation data for 1960-2019. The daily precipitation for the major 7 synoptic stations in the Guangdong province of China was analyzed. It is found that the spatiotemporal heterogeneity were the distribution characteristics of PRD precipitation. In terms of spatial distribution, more precipitation value in the eastern coastal areas of Guangdong province. In general, the average annual precipitation presented an increasing trend form 1960 to 2019. At the same time, the probability and intensity of extreme precipitation with increasing tendency were analyzed in this time period. It was indicated the continuing situation of climate fluctuation that adjusted the precipitation regime of Guangzhou. Summer became the season with the largest number of statistically significant trends of extreme precipitation, mostly increasing ones.
Study on the Construction of Water Environment Promotion Joint Control and Joint Regulation System in Plain River Network Area
Authors: Xie Chen , Pan Xiaobao , Ding Rui , Liu Guoqing , Liu Yang
Published: March 2021

There are many river networks in Southeast plain cities of China, such as dense river network, many water projects, poor connectivity, strong pollution load into the river, and difficulty in regulation and control. The water environment problem of river network has become the bottleneck restricting the sustainable economic and social development of plain river network area. In order to improve the river water environment, it is very important to carry out reasonable intelligent regulation of regional river system. In view of the current situation that the water environment regulation is mainly based on manual operation and has not formed intelligent dispatching decision-making, this paper integrates the technology of water power and water quality joint control of urban river network, researches and develops the joint control and joint dispatching system of water environment improvement in plain river network area, and establishes a full coverage, full element three-dimensional monitoring and warning, dispatching and intelligent decision-making system, driven by monitoring data, with model as the core and remote control as the core with the goal of hydrodynamic, water level and water quality as the target, relying on the model cloud, the intelligent one click precise scheduling is realized.
Effect of Vegetation on the Flow of a Partially-Vegetated Channel
Authors: Tang Xiaonan , Guan Yutong , Zhang Yujia , Zhang Wenxuan , Jiang Yanzhen , Liu Tong , Yi Xintong
Published: March 2021

A vegetated channel commonly exists in the natural environment. Over recent decades, many researchers have taken an interest in this field. The hydraulic characteristics of flow over vegetated channels are complex. Vegetation significantly affects the flow resistance and turbulence, resulting in sediments, nutrients, and contaminants transportation. Thus, understanding the impact of vegetation on flow structures is important for river and environment management. However, most attention on vegetated channel flow focuses on single-layered vegetated channels. There are few studies on the impact of double-layered, partially placed vegetation on open channel flow. To fill this research gap, this paper aims to investigate the impact of vegetation on the flow velocity of a double-layered, partially placed vegetated channel.
Experimental Study of Smooth Asymmetric Compound Channels Flow: An Investigation of the Interaction of Flow Using Scaling Argument for Prediction of Overall Discharge
Authors: Singh P , Tang X , Guan Y
Published: March 2021

A simple model for the apparent shear stress on the vertical interface between the floodplain and main channel in asymmetric smooth compound channels is proposed using experimental data obtained in this study. The turbulent structure, including Reynolds shear stress in asymmetric compound channel flows, is investigated for three different flow depths. The lateral distribution of the apparent shear stress obtained shows that the total apparent shear stress has a negative peak near the junction edge in the main channel. Furthermore, the intensity of the advection terms and the Reynold shear stress near the interface are investigated as the function of the bankfull height and floodplain width. The momentum transport due to Reynolds stress and secondary current between main channel and floodplain is finally modeled as depth ratio using scaling argument. The validation of the current model on three datasets shows an accurate prediction of overall discharge for the asymmetric smooth compound channels.
Design and Research of Micro Pile Drilling Rig for UHV Transmission Line in Mountainous Area
Authors: Liu Ruijun , Liu Quan , Liu Fuhai , Tu Lei , Zhang Jixu , Guan Qing
Published: March 2021

In order to comply with the local economic development and reduce the project investment, the UHV line projects are mostly along the hilly areas, and the mountainous areas are mostly difficult to construct. At the same time, the mountainous environment is complex, the traffic is inconvenient, and it is difficult for large machinery to transport to the operation site, which makes the construction of UHV line foundation pile less mechanized, and has always relied on manpower and small tools. With the large-scale development of power grid construction, the problems of labor intensity, poor operation safety and low construction efficiency caused by relying on human construction are increasingly apparent. In view of this kind of problem, the micro pile drilling machine realizes the mechanized construction of micro pile foundation in UHV transmission line project through modular design scheme. Micro pile foundation is a new type of light foundation pile foundation (pile diameter is generally 300-400mm) specially designed for mountainous UHV transmission line engineering. It has the advantages of small pile diameter, small working surface, small hole digging torque, high bearing capacity, and small excavation volume, which is conducive to environmental protection. It is a special equipment suitable for the construction of micro pile foundation under complex mountain conditions.
Design of WZFT Mountain Rig in Mining Industry
Authors: Liu Ruijun , Wang Guigen , Li Yong , Fu Yanlong , Huang Guanglong , Ding Xiaowu
Published: March 2021

With the development of China’s mining industry, in order to promote China’s mineral exploration to the deep to meet the new round of industry demand, mining enterprises on mining machinery and equipment demand is increasingly high, especially drilling, field mining equipment; Improve mining machinery equipment level and efficiency of artificial intelligence is necessary, and can eliminate the safety hidden trouble, the comprehensive implementation of related equipment localization, an urgent need to study to design new functional drill, solution to meet the construction efficiency, reduce the risk of construction personnel safety, reducing the project cost and reduce soil and water loss protect the environment. The mine machinery equipment WZFT designed in this paper is specialized in drilling equipment used for blasting in various mines and drilling holes, and it is produced by Jiangxi Dongrui Machinery Co., LTD., and it is proposed to develop drilling machine in the direction of intelligentization and unmanned in the future.
Technologies for efficient development of hydrocarbon resources on the Arctic and sub-Arctic shelf of Russia
Authors: Dziublo Alexander , Storozheva Anna
Published: March 2021

This article discusses the technical capabilities and results of the application of modern technologies for geological exploration, well drilling, development and operation of offshore oil and gas fields on the Arctic and sub-Arctic shelf of Russia. Based on the scientific and production experience of the authors, analysis of the results of search and exploration in the seas of the Arctic and the Far East, a consistent system of technologies for geological exploration is proposed. The use of such an integrated set made it possible to discover large and unique oil and gas fields in the Barents-Kara region (Medynskoe-more, Dolginskoe, Varandey-more, Kamennomysskoe and others). The features of geophysical work and technologies for achieving high quality seismic material the transition zone (land-sea) in the Ob bay, where due to the presence of permafrost in the upper part of the geological section, there is a significant change in the velocities and absorbing properties of rocks, are shown. Using the example of the Varandey-more field, a technology for integrating 3D deep-sea seismic data and seismic surveys in the land-sea transition zone is described, which made it possible to update the geological model of the field, detail the structural plans of oil-bearing horizons. As a result, after the completion of the interpretation of the survey data in the transit zone, it was recommended to drill an exploration well in the southern part of the field. It has been substantiated that the efficient shelf field exploitation is ensured through the use of new technologies (drilling of long horizontal wells; 4D seismic surveys at the Piltun-Astokhskoye and Lunskoye fields; well designs providing high gas production rates; subsea production at the Kirinskoye field).
Improvement of Design of Diesel Injector Nozzles
Authors: Markov Vladimir , Devyanin Sergey , Kamaltdinov Vyacheslov , Sa Bowen
Published: March 2021

The relevance of the article is explained by the necessity of improving fuel spraying and mixture formation processes in diesel engines. A design of injector nozzles enhancing the quality of the fuel injecting and spraying in diesel engines was proposed. The improvement of these processes is achieved by using a modified nozzle with different lengths of nozzle holes for injectors asymmetrically installed in diesel engines. Experimental studies of a D-245.12S diesel engine equipped with the injector nozzles serially produced and the modified injector nozzles were carried out. The possibility of improving the exhaust gas toxic characteristics of the diesel engine equipped with the modified injector nozzles was demonstrated. The installation of such nozzle in the diesel engine has allowed reducing the emission of nitrogen oxides by 2.1%, of carbon monoxide by 9.5%, and of unburned hydrocarbons by 10.9%, and reducing the average specific effective fuel consumption by 2.5 g/(kW•h), when the engine was operating in the 13-mode cycle ECE R49.
Specialized ecological polygon as one of the tools to reduce pharmaceutical pollution of the environment
Authors: Belov Vladimir , Komandresova Tatyana , Samarkin Alexander
Published: March 2021

The article discusses the problems of pollution of natural objects of the environment by medicines. The main sources of pharmaceutical waste, the causes of their occurrence, as well as the ways of penetration of drugs, the results of their metabolic transformation in the bodies of patients into environmental systems are characteristic. It has been shown that the main suppliers of pharmaceutical waste are medical organizations, chemical and pharmaceutical companies and the population. It is noted that the main channels of penetration of medicines into the environment are wastewater and landfills. Some data on the emergence of pharmaceutical substances in the natural environment are analysed. The composition of the recommendations and measures necessary to reduce the level of environmental risks associated with pollution is described. Particular attention is paid to the Environmental Monitoring Service, which provides laboratory support for environmental monitoring of environmental facilities, including hydro- and geochemical analysis of water, soil and air environment. It is proposed to improve the effectiveness of the environmental monitoring service in view of the degree of impact of controlled drugs on the natural environment by deploying a specialized ecological polygon.
Blended learning as a tool for professional training of specialists for the Arctic region: modern practices in the context of digitalization of education
Authors: Shcherbakova I O , Belozerova N V , Mahmudova T V
Published: March 2021

Blended learning now is becoming a popular technology which combines the traditional methods and tools with modern e-learning strategies. This paper focuses on contemporary approaches applied in the sphere of professional training of specialists for the Arctic and examines the experience of the two leading Universities of Russia which train highly qualified personnel for the Arctic region. In the context of digitalization of education a combination of different elements of electronic information and educational environment has been created and is actively developing. The authors use the official data and methodological documents and describe the latest practices applied in educational process in the context of digitalisation of education. The educational practices presented by the researchers reflect the experience of using the information and training portal “Arctic Safe” created in Saint-Petersburg University of the State Fire Safety Service and show capabilities of the electronic educational environment including distance learning system “FARVATER” which is used in Admiral Makarov State University of Maritime and Inland Shipping. The represented systems provide the students and teachers as well as the administration with the effective tools to organize the educational process.
Improving oil recovery for Arctic offshore oilfields using efficient multifunctional systems
Authors: Naletov V A , Glebov M B , Yu Naletov A
Published: March 2021

This work presents the main properties of multifunctional systems designed for improving oil production for Artic offshore fields. The processes were developed using a system approach to the optimal organization of complex technological objects. This approach employs the principles of general systems theory, which are based on information theory developed by C. Shannon and W. Weaver and can be used to formulate the organization criteria of a technological system with hierarchical structure. This can be applied in technology for creating multifunctional processes with synergistic properties. Technological solutions were designed in order to address a number of important issues associated with the development of offshore oil fields in the Artic region, namely: improving oil recovery, energy saving, environmental problems (problems associated with the conservation of a unique ecosystem) and ensuring the operation of the production platforms. These solutions will allow to solve these problems simultaneously in multifunctional systems that combine power generation modules based on the Brayton and Rankine cycles and modules for carbon dioxide capture. The efficiency of the proposed solution exceeds that of analogous solutions overseas.
Research of the features of the formation of the structure and properties of building composites based on clinker-free binders of alkaline activation with the use of unconditional natural and secondary raw materials
Authors: Salamanova Madina , Murtazaev Said-Alvi , Khubaev Magomed , Gatsaev Zurab
Published: March 2021

The anthropogenic load on the natural resource potential of the planet is growing rapidly. Therefore, special attention is paid to the development of less costly and low energy-consuming technologies for obtaining new building materials. Those materials do not require high-temperature and expensive technological processing, and this will allow the use of local secondary and substandard raw materials. The development of formulations for linker-free binders of alkaline activation based on fine powders of aluminosilicate nature will make it possible to obtain new effective building composites. The work reveals issues related to the theoretical foundations of the structure formation and strength of cement stone based on an alkaline activator. The research results, in our opinion, have a practical importance for the construction industry, since the proposed formulations of clinker-free cements can replace expensive and energy-intensive Portland cement, allowing creating strong and durable concrete and reinforced concrete structures. The results presented in this article were obtained in the framework of research on the implementation of scientific project No. 05. 607.21.0320. “Development of technology for new building composites based on linker-free binders of alkaline activation using substandard natural and secondary raw materials” supported by the Federal Target Program “Research and Development in Priority Areas of Development of the Scientific and Technological Complex of Russia for 2014-2020” The unique identifier for the agreement is RFMTFI60719X0320.
The public administration of the socio-economic development of the Arctic zone based on a stakeholder approach
Authors: Sakharova Swetlana , Avdeeva Irina , Golovina Tatyana , Parakhina Larisa
Published: March 2021

The need to form an effective system of public administration of the Arctic zone socio-economic development is driven by the current processes aimed at the working out of a new Arctic Development Strategy until 2035. This strategy should combine the activities of national projects, government programs, investment projects of state corporations, programs for the development of the Arctic regions and cities. The purpose of this study is to develop theoretical and methodological provisions of the stakeholder approach in the system of public administration of the Arctic development. Scientific novelty consists in the formation of an effective system of public administration, taking into account the specifics of economic and managerial relations with stakeholders, which is aimed at the balanced development of the Arctic. The study presents an assessment of the current state regional policy on the territory of the Arctic zone of the Russian Federation. A model of public administration of its socio-economic development based on a stakeholder approach was developed. Strategic measures of state management of the Arctic were identified on the basis of the regulation of the effects distribution between stakeholders.
Assessment of factors affecting the development and implementation of investment projects in the Russian Federation Arctic Zone
Authors: Babkina Lyudmila , Kozin Mikhail , Skotarenko Oksana
Published: March 2021

The article gives reasons for dividing strategic goals of Arctic Zone socioeconomic development into levels. The first level includes major mid-term goals until 2035, the second one strategic vectors of development or condition goals, and the third one programme goals, including the government programme “Socioeconomic Development of the Russian Federation Arctic Zone”. This hierarchy of goals is based upon a systemic, comprehensive, and programme-goal methodological approach and an analysis of regulatory documents applicable to socioeconomic development of and investment activities in the Russian Federation Arctic Zone. Therefore, any government programme, including the Socioeconomic Development of the Russian Federation Arctic Zone is aimed at achieving major strategic development goals and based on successful implementation of investment projects. The authors have therefore developed and tested a method to assess the importance of factors affecting implementation opportunities and threats (risks) of an investment project. The article contains an assessment of opportunities and threats (risks) caused by small-scale and large-scale external factors and internal factors affecting successful implementation of a company project in the Russian Federation Arctic Zone.
The model of an information system for monitoring remote sensing data of the Arctic region
Authors: Bizyukin Makar , Abrahamyan Gennady
Published: March 2021

The work is aimed at developing a model of an information system for the analysis and monitoring of remote sensing data by the example of processing hyper- and multispectral satellite images, which are widely used to analyze the state of static and dynamic objects in the Arctic region of the Russian Federation. For automatic analysis and decryption of Arctic data in the development of the model, methods of high-performance computing, radiometric calibration, filtering and clustering of images, as well as intelligent data processing methods using deep learning convolutional neural networks were used. Object-oriented design and united modeling language notation were used to develop the model. A data-level model, a conceptual model of the structure of system modules, including a resource storage center, a resource and results management center, and a presentation-level interface have been developed. To develop a diagram of the use cases of the information system, the structure of actors, use cases and their interrelations were identified. The logical model of the information system was created on the basis of a class diagram consisting of the Resource and Results Manager Center, Intellectual Information System, Functional Neural Modules packages. The practical significance of the study is due to the fact that the results obtained will allow the development of a prototype of an information system that can be used for effective monitoring of “useful data” of the Arctic region of the Russian Federation, as well as to automate the processes of analysis, updating, storage and processing of data from objects in various areas of the Arctic infrastructure.
Russia’s geopolitical and socio-economic interests in the Arctic: regulatory issues
Authors: Boldyreva Olga , Ilyin Viktor , Sergeeva Galina , Plesnyakova Vera , Mezinova Olga , Deshin Mikhail
Published: March 2021

This article is a comprehensive analysis of the Arctic legislation of the Russian Federation in the context of the implementation of the main geopolitical and socio-economic interests of the country in the Arctic region. The relevance of the presented research is determined by the need for further development of international legal norms regulating various aspects of the development of the Arctic region, as well as domestic legislation that defines Russia’s strategic interests in the Arctic zone and the competence of state authorities in the implementation of these interests, taking into account the basic principles and provisions of international public and private law and the Constitution of the Russian Federation.
Multi-objective groundwater management using genetic algorithms in Kerbala desert area, Iraq
Authors: Khalaf Rasul M. , Hassan Waqed H.
Published: March 2021

Kerbala desert is one of the most important areas in Iraq, due to the large number of groundwater aquifers in the region. Based on this, many agricultural investment projects have been established in this area recently, with multiple new wells being drilled in the desert. All such wells penetrate the Dammam confined aquifer to a depth of 260 to 300 m, and uncontrolled use of these wells, and the additional wells expected as the area develops, is likely to lead to problems with groundwater sources, including depletion of water levels, well interference, and groundwater pollution. This study introduces a multi objectives groundwater management model based on an integrated simulation-optimisation (S/O) model. The simulation of groundwater flow was developed using a finite-difference numerical model, MODFLOW, under GMS software for various conditions, and evaluation of calibration of the transient model was determined by observing the measured and calculated aquifer heads. A multi-objective optimisation model was applied to maximise the pumping rate and minimise pumping costs, and this was solved using a genetic algorithm method supported by two further mechanisms, Pareto optimality ranking and fitness sharing. A set of Pareto optimal solutions as determined in the final generation was thus created for the multi-objective function (maximum pumping rate and minimum pumping cost) to help decision-makers (DM). Based on the Pareto solutions set, a DM or the designer may thus choose a preferred solution, or a compromise solution may be derived by considering the full set of Pareto optimal solutions.
Experimental Study on Beam-Column Connections of Concrete Encased Cold-formed Steel Beams to Concrete-filled Steel Tube Columns
Authors: Mosheer Khamail Abdul-Mahdi , Dawood M B , Ghalib M H
Published: March 2021

Experimental testing was done to investigate the flexural behaviours of internal roof beam-column connections. Four specimens were studied under static loads, one of which was specified as a reference reinforced concrete beam-column connection with regular bars as a conventional reinforcement for beam and column. The other specimens featured cold-formed steel plates with the equivalent area to regular bars as reinforcement, with square steel tube cross-sections filled with concrete used for columns. The results showed an increase in load carrying capacity and toughness for the experimental specimens as compared with conventional reinforcement beam-column connection. The concrete prevented local buckling of the cold-formed steel sections and improved the flexural bending capacity.
Development of a model to estimate concrete compressive strength using ultrasonic testing based on previous models
Authors: Mahmmod Laith Mohammed Ridha , Alameer Sara Alaa Abed , Abdulrasool Abdulrasool Thamer
Published: March 2021

Ultrasonic pulse velocity test is one of the most important non-destructive tests for exploring the essential properties of concrete such as compressive strength. Many previous researchers have examined relationship between ultrasonic pulse velocity and the compressive strength of concrete, developing equations to link these factors; however, comparing the calculated compressive strengths created by applying different equations to the same ultrasonic pulse velocity value, the results are rarely even close. This research aimed to develop new model based on seven such previous equations using a statistical program (Minitab) to calculate the compressive strength of concrete more accurately. The compressive strength thus obtained was equal or very close to the average results obtained from all seven equations, and the results were verified against a dataset of 100 results from ultrasonic pulse velocity test for multi-story concrete building. The obtained results were also compared with the average results from the seven equations used within the experimental program. The comparisons confirmed that, the new model can be used as an alternative approach to calculating compressive strength instead of using all seven equations.
Acoustic and thermal insulation properties of recycled aggregate mortar
Authors: Hussein W Gh Abdul , Al-Sultan A A , Al-Ani F H
Published: March 2021

This study focuses on the design of a lightweight cement mortar with recycled fine aggregates of wood, plastic, and glass. The normal fine aggregate (sand) was replaced with 20%, 40%, and 60% by weight of sand of recycled aggregates, prepared by cleaning wood sawdust, broken plastic, and broken glass with mechanical milling and then using a mill to obtain a similar gradation to that of the sand. The main goal of this paper was to study the effects of using these recycled aggregates on acoustic and thermal properties as compared with those of the reference cement mortar. Acoustic insulation tests were thus carried out on samples with dimensions of 23 × 23 × 0.8 cm prepared for this purpose at the age of 28 days, with three models for each replacement ratio. The acoustic isolation results showed that cement mortar with sawdust at replacement ratios 20%, 40%, and 60% showed better acoustic isolation properties than cement mortar with plastic and glass with the same replacement percentages or ordinary cement mortar. The thermal insulation of the samples was tested in samples with dimensions of 10 × 5 × 2 cm at 28 days. The results for thermal conductivity coefficients were 0.2353 W.m-1K-1, 0.1981 W.m-
1K-1, and 0.1609 W.m-1K-1 for the replacement ratios 20%, 40%, and 60%, respectively. These results show that the cement mortar with sawdust offered less thermal insulation than cement mortar with plastic debris, while cement mortar with crushed glass was even less thermally isolated.