bluuebunny/crossref_metadata_2025 huggingface dataset:
Psychodiagnostic toolkit of combat stress for aviation specialists
Authors: Maksymenko Sergey , Blinov Oleg , Shatilo Yuliya , Timkin Ivan
Published: May 2021

The article is dedicated to the analysis of psychological techniques used in psychological practice to determine the combat stress among aviation professionals. The relevance of the article is due to the active interest of modern researchers in this problem as the appropriate psychological toolkit doesn’t exist. The study is performed in compliance with medical psychology, together with the study of combat stress phenomenology and the development of psychological tools for psychodiagnostics, psychocorrection, and psychotherapy. The author presents express-methods that allow both to establish the signs of combat stress and to assess it in points, to work with tools in the field at any weather and season or hospital conditions. The suggested comprehensive approach to the study of the combat stress phenomenon among the specialists through its understanding of the integrative internal content where one of its elements is psychological resources. This approach allows us to study combat stress in the dynamics of its changes, as a state of mental stress among the servicemen during their adaptation to combat conditions using the resource potential. The analysis showed that the proposed methods are universal and allow a comprehensive consideration of the combat stress problem among the servicemen.
New educational technologies in the educational and professional motivation of undergraduate students in the field of ecology
Authors: Shefer Olga , Kraineva Svetlana , Lebedeva Tatyana
Published: May 2021

The article presents a study of the influence of the specifics of the formation of the motivational sphere of undergraduate students on their readiness and ability to perform their labor functions for obtaining a quality education. High-quality education is the basis for a decent life and sustainable personal and social development, which contributes to changing the labor market in all countries of the world, blurring the boundaries between the physical, digital, and psychological and biological spheres. The study of this topic is extremely important for Russia, which seeks to overcome the negative consequences on the labor market and lag behind global trends in development through the implementation of the strategy 2016-2030. As a result of the work, a cluster of pedagogical technologies “UnInd of motivations” was created, which has wide opportunities and allows to implement the educational process in a new way in the modern conditions of the university, namely: to create conditions for improving the training of a university student, increasing the motivation of learning by solving case problems of a practice-oriented nature, to create conditions for further self-improvement in the professional sphere.
Energy-saving potential of heating networks in Russia
Authors: Gagulina Natalya , Zaedinov Andrei
Published: May 2021

The paper is devoted to the study and search for solutions to one of the most important problems within the modern Russian economy – the problem of energy saving. The relevance of this topic is due to the unprofitability of the heat supply industry, the one main reasons of which is the unsatisfactory condition of fixed assets. The paper considers the most important element of heat supply: the transfer of heat energy to consumers through the heat network. It has been presented an overview and analysis of the state of heating networks in 2014-2019 on average in Russia and particularly: in Moscow, St. Petersburg, and the Northwestern Federal District. The value of economic losses incurred by heat supply organizations due to heat losses in their heating networks is obtained. In monetary terms, the energy-saving potential was obtained while reducing heat losses in the pipelines up to 4%. For the whole country, this potential amounted to more than 100 billion rubles a year. As the analysis of the experience of foreign countries with similar climatic conditions, such as Denmark, Norway, and Finland, has shown, Russia can significantly increase the efficiency of heat supply through the use of innovative technologies.
Controlling in the management of a regional power grid company
Authors: Sovetov Pavel , Sovetova Nadezhda
Published: May 2021

The tasks of improving the methods and tools of strategic enterprise management determine the relevance of including the controlling mechanism in the process of managing the enterprise's activities. The purpose of the paper is to substantiate the need to use controlling in the process of strategic enterprise management. The authors use general logical methods and research techniques: a systematic approach, generalization, analysis and synthesis. The paper notes the plurality of views of management theorists and practitioners about the essence of controlling and discrepancies in its functional purpose, which entail the problems of organizing and effectively using the controlling mechanism in enterprise management. In this regard, the authors emphasize the view of controlling as a function of strategic management, systematize the list of implemented controlling tasks and factors that predetermine them, indicate the special role and place of controlling as a kind of tool in the analytical mechanism of self-assessment of the effectiveness of the goal-setting and goal-implementing function of enterprise management, the action of which (i.e. tool) is possible with an adjusted feedback model in the control loop. The prerequisites have been identified and a model for the consistent development of controlling in enterprise management has been tested in relation to the object of research - the regional power grid company PJSC “IDGC of North-West”. The result of the first stage of mastering the controlling functionality is the ability to partially relieve the top management of the company from operational and technical issues in favor of preparing and implementing management decisions of a strategic focus and content. The spectrum of orientation of the controlling functional in the management of PJSC “IDGC of North-West” towards achieving tactical and strategic goals for the long-term existence and development of the company is shown. Prospects for further research into the problem of organizing effective controlling are in the development of methodological support for the process of integrating information flows using digital technologies. Scientific novelty lies in the presentation of controlling as a management function that ensures the company’s activities in accordance with plans in the interests of achieving established goals.
Evaluation of the effective porosity of an open cell foam material for using in heat and mass transfer numerical simulations
Authors: Soloveva Olga , Solovev Sergei , Zaripova Rimma , Khamidullina Faniia , Tyurina Marina
Published: May 2021

A comparison of the efficiency of the open cell foam (OCF) models is carried out. Geometrical models are constructed by the methods of simple cubic, body-centered cubic, and face-centered cubic. The parameter of the material efficiency is defined as the composition of the material surface area and the gas residence time in the porous media. The analytical evaluation shows different values of effective porosity for different construction models of the material. In this case, for all considered models, the effective porosity is in the range of 0.741-0.821.
Visualization of the sustainable development model of the green core of the agglomeration: the neogeography of the Chelyabinsk urban pine forest
Authors: Gordeev Sergey , Kocherov Andrey , Merker Vera
Published: May 2021

In the study on building a model of spatial development, the issues of problem-oriented zoning of territories, transformation of the settlement framework, integration of the most significant objects of social transformations are considered. Such objects in the heterogeneous social Eurasian space are, first of all, the zones of agglomerations. Taking into account the regional specifics when identifying a heterogeneous set of key spatial objects, the main provisions of the spatial development of the territory as a complex multi-level socio-economic system are determined. The solution to the issues of strategic planning of such systems is associated with the problematic adaptation of visualization technologies, the joint use of a special format of cartographic and digital information. The main research results create the prerequisites for a significant expansion of the number of tasks of managing regional and municipal development of the natural and ecological framework.
Balance assessment of material and energy biosphere flows and the energy industry in an industrial region
Authors: Dvinin Dmitry , Davankov Aleksey
Published: May 2021

The balance assessment of biosphere material and energy flows and those resulting from economic activity in the industrial region is carried out. The analysis is based on the use of stability indicators of the region's socio-ecological and economic system. For balance assessment of material and energy biosphere flows and economic activity, the total material input criterion was used, where the consumed natural resources are reduced to a single value. It was found that the functioning of the energy sector operating on fossil fuels created significant imbalances in the material and energy flows. The balance indicator is calculated for the regions of the Ural Federal District. In all regions of the Ural Federal District, except for the Yamal-Nenets Autonomous Area, the balance indicator is higher than the presence of general instability. The study allowed determining the magnitude of the ecological and economic effect in developing promising renewable energy sources. In 2 regions of the Ural Federal District, the scenario of replacing traditional energy with renewable energy will reduce the material intensity, which means that it will increase the level of balance of material and energy flows by more than 10 times.
Current state of production and consumption of rhenium abroad
Authors: Argimbaev Kaerbek , Ligotsky Dmitry , Loginov Egor
Published: May 2021

The relevance of the article does not raise any doubts, especially in the context of modern consumption of rhenium. Rhenium is an industrial metal that has gained increasing recognition and is widely used not only in Russia but also in foreign countries, mainly in the form of alloys with other elements, imparting special physicochemical properties to alloys based on wolfram and molybdenum. The most popular alloys with the addition of molybdenum and tungsten are recognized. Adding of a minor amount of rhenium reduces the transition temperature of wolfram and molybdenum to the fragile state and at the same time makes it possible to maintain elasticity at high temperatures. The objective of this article is to analyze the demand for rhenium abroad and its production by analyzing the market for mineral raw materials, by studying reports, literary sources, reports of companies for the production and consumption of rhenium, which are leaders in their field of activity. The article presents the results of the analysis of rhenium global production and consumption.
Psychometrische Evaluation einer deutschen Version der Lang- und Kurzform der Prejudice towards People with Mental Illness Scale (PPMI-D)
Authors: Sander Christian , Rieckhof Sophia , Peter Lina-Jolien , Horsfield Philipp , Speerforck Sven , Angermeyer Matthias C. , Schomerus Georg
Published: May 2021

Ziel der Studie Vorstellung einer deutschen Version der Prejudice towards People with Mental Illness Scale in Lang- (PPMI-DL) und Kurzform (PPMI-DK) und psychometrische Evaluierung an einer deutschen Bevölkerungsstichprobe.

Methodik Deutsche Übersetzung und Überprüfung auf Passung zur Originalversion nach Rückübersetzung und Durchführung einer Online-Befragung (N = 1004).

Ergebnisse Itemschwierigkeiten und Trennschärfen liegen im wünschenswerten mittleren Bereich. Hohe bis exzellente interne Konsistenzen (PPMI-DL: α = 0,919; PPMI-DK: α = 0,872) in der Gesamtskala. Mittels konfirmatorischer Faktoranalysen konnten die 4 Subskalen der Originalskala bestätigt werden. Mittlere Korrelationen mit autoritären Einstellungen (KSA-3) und gering negative Zusammenhänge mit Sozialer Erwünschtheit (KSE-G). Normwerte für die PPMI-Subskalen werden berichtet.

Schlussfolgerung Die PPMI-D kann im deutschsprachigen Raum eingesetzt werden, um Vorurteile gegenüber psychisch kranken Menschen zu erheben.
Male and Female Collegiate Ice Hockey Athletes’ Body Composition Over Competitive Seasons
Authors: Dengel Donald R. , Roelofs Erica J. , Czeck Madeline A. , Bosch Tyler A.
Published: May 2021

Eighty-three male and female (49/34) athletes underwent determination of total fat mass (FM), lean mass (LM), bone mineral density (BMD) and visceral adipose tissue (VAT) by dual X-ray absorptiometry during the pre-season, in-season and off-season. Athletes were classified by position of Goalie (G; M/F=7/6), Forward (F; M/F=26/18), or Defenseman (D; M/F=16/10). In males, all positions were similar in weight, FM, LM, BMD and VAT. In females, F weighed less than D and G. FM and VAT was lower in F than D and G, but D was not different from G. LM was lower in F compared to D, but not G, with no differences between D and G. There were no differences in BMD between positions. There were no seasonal changes in males for body composition variables. In females, FM, LM and VAT decreased from pre-season to in-season, while BMD increased. From in-season to off-season, LM increased and BMD decreased. From off-season to pre-season, FM and VAT increased. In conclusion, there were no differences across position or seasonal changes in body composition in males. However, there were positional and seasonal changes in body composition in females, indicating possible differences in training regimens during the off-season compared to males.
Organocatalyzed Oxa-Diels–Alder Reactions: Recent Progress
Authors: Biswas Anup , Kundu Samrat , Maji Modhu Sudan , Pal Dhananjoy , Pal Amit
Published: May 2021

The oxa-Diels–Alder reaction is a straightforward, atom-economical process for the construction of six-membered oxacycles, which are privileged structures due to their very common occurrence in several pharmaceuticals and natural products. As with many other asymmetric transformations, organocatalysis provides an elegant pathway to their synthesis via [4+2] annulation under mild reaction conditions. The oxa-Diels–Alder reaction utilizes either an α,β-unsaturated carbonyl as an oxa-diene with a suitable dienophile or a simple carbonyl as a dienophile with other dienes. A range of organocatalysts has been explored in the past decade to execute this strategy. The catalysts induce stereoselectivities via two basic reactivities: (1) The formation of chiral intermediates, or (2) selectively activating suitable reactants via a transition state. The present short review compiles organocatalyzed asymmetric oxa-Diels–Alder reactions published over the last ten years, along with detailed discussions on mechanistic approaches.

1 Introduction

2 Catalysis through Covalent Activation

2.1 N-Heterocyclic Carbenes

2.2 Amines

2.3 Isothiourea Catalysis

2.4 Phosphines

3 Catalysis through Non-Covalent Activation

3.1 Bifunctional Amines

3.2 Brønsted Acids

3.3 Guanidines

4 Multicatalysis through Both Covalent and Non-Covalent Activation

5 Conclusion
Validation of Arylphosphorothiolates as Convergent Substrates for Ar-SF4Cl and Ar-SF5 Synthesis
Authors: Cornella Josep , Wang Lin , Ni Shengyang
Published: May 2021

In this manuscript we describe the oxidative fluorination of aryl phosphorothiolates to access Ar-SF4Cl compounds. These compounds serve as precursors for the highly coveted Ar-SF5 compounds. The use of phosphorothiolates as starting materials permits access to Ar-SF4Cl from a wide variety of available starting materials, namely boronic acids, diazonium salts, aryl iodides, thiophenols, or simple arenes. The protocol has been demonstrated for >10 examples and showed good tolerance to various functional groups. Finally, we demonstrated that AgBF4 can be used as a fluorinating agent, affording good yields of an Ar-SF5.
Surface structure repels water droplets at room temperature, ice at colder temperatures
Authors: McConnon Aili
Published: May 2021

Designing a doubly reentrant cavity structure that achieves promising hydrophobicity and icephobicity
Influence of Cr and Al to FeCoNiCrxAl2-x alloys synthesised by mechanochemistry
Authors: Zhang Yingzhe , Li Xiaopeng , Qin Qingdong , Li Juan , Zhao Honglong , Gao Xingyong , Su Xiangdong , Chen Ding
Published: May 2021

In this study, soft magnetic FeCoNiCrAl high-entropy alloys (HEAs) were synthesised by high-energy ball milling using Fe, Co, Ni, Cr and Al powders as raw materials. The phase evolution was detected by X-ray diffraction, and the results showed that only 12 h were required to convert all the raw materials into the HEAs nanoparticles. It was shown that the prepared particles formed aggregates of approximately 1 μm in size. Furthermore, the influence of the amounts of Cr and Al on the formation process, magnetic properties and microwave absorption of the FeCoNiCr xAl2- x alloys was investigated. The saturation magnetisation reached 80.43 emu g−1 when x = 1, and the minimum calculated reflection loss reached 41.99 dB at 2.40 GHz with a layer thickness of 4.2 mm when x = 1.5.
Fuelling the female athlete: Carbohydrate and protein recommendations
Authors: Moore Daniel R. , Sygo Jennifer , Morton James P.
Published: May 2021

Optimal carbohydrate and protein intakes are vital for modulating training adaptation, recovery, and exercise performance. However, the research base underpinning contemporary sport nutrition guidelines has largely been conducted in male populations with a lack of consensus on whether the menstrual phase and associated changes in sex hormones allow broad application of these principles to female athletes. The present review will summarise our current understanding of carbohydrate and protein requirements in female athletes across the menstrual cycle and provide a critical analysis on how they compare to male athletes. On the basis of current evidence, we consider it premature to conclude that female athletes require sex specific guidelines in relation to CHO or protein requirements provided energy needs are met. However, there is a need for further research using sport‐specific competition and training related exercise protocols that rigorously control for prior exercise, CHO/energy intake, contraceptive use and phase of menstrual cycle. Our overarching recommendation is to use current recommendations as a basis for adopting an individualised approach that takes into account athlete specific training and competition goals whilst also considering personal symptoms associated with the menstrual cycle.
Wetland loss in Turkey over a hundred years: implications for conservation and management
Authors: Ataol Murat , Onmuş Ortaç
Published: May 2021

The aims of this study were to provide a complete inventory of wetlands in Turkey including their past status (1910–1930) in comparison to the present time (2014). The types of wetlands and their area sizes were determined by using cartographical maps of 1/200,000 in scale made between 1910s and 1920s vs. 2006 CORINE Land Cover data, which were updated with Landsat 8 satellite images in 2014. The effect of possible climate change on wetlands sizes various local, national and regional rainfall datasets were analysed by correlation and regression analysis. A hundred years ago, the total number of natural wetlands was 1299 with a total surface area of 1,376,505 hectares. In 2014, the total number of natural wetlands had decreased to 900, with a total surface area of 1,085,936 hectares, so that 21.2% of the original wetlands were lost (291,339 hectares). The observed changes in the number of wetlands and their relative sizes cannot be attributed directly to changes in climate. Wetland drainage was largely responsible for observed wetland losses, but local changes in precipitation regimes partially contributed to this loss. Urgent conservation and restoration of wetlands are recommended to avoid further loss of wetlands in Turkey.
Large N-ightmare dark matter
Authors: Morrison Logan , Profumo Stefano , Robinson Dean J.
Published: May 2021

A dark QCD sector is a relatively minimal extension of the Standard Model (SM) that admits Dark Matter (DM) candidates, but requires no portal to the visible sector beyond gravitational interactions:
a “nightmare scenario” for DM detection.
We consider a secluded dark sector containing a single flavor of light, vector-like dark quark gauged under (N).
In the large-N limit, this single-flavor theory becomes highly predictive, generating two DM candidates whose masses and dynamics are described by few parameters:
a light quark-antiquark bound state, the dark analog of the η' meson, and a heavy bound state of N quarks, the dark analog of the Δ++ baryon.
We show that the latter may freeze-in with an abundance independent of the confinement scale,
forming DM-like relics for N ≲ 10, while the former may generate DM via cannibalization and freeze-out.
We study the interplay of this two-component DM system,
and determine the characteristic ranges of the confinement scale,
dark-visible sector temperature ratio, and N that admit non-excluded DM,
once effects of self-interaction constraints and bounds on effective degrees of freedom at the BBN and CMB epochs are included.
A highly birefringent photonic crystal fiber with compact cladding layers suitable for fiber optic gyroscope application
Authors: Alishacelestin X , Sivanantha Raja A , Selvendran S
Published: May 2021

A size reduced cladding layer of highly Birefringent photonic crystal fiber (PCF) that is suitable for fiber optic gyroscope application is proposed in this paper. A pair of minimized and enlarged air holes in the innermost layer of PCF is responsible for high birefringence and enlarged outer layer air holes are responsible for low confinement loss. The optimized geometrical parameters for this novel PCF are chosen so as to ensure high birefringence and low confinement loss. Fabrication of this proposed PCF is simplified by reducing the cladding layers. Obtained birefringence of this PCF is about 6.1 × 10−4 and the confinement loss is about 2.8 × 10−4 dB km−1.
Simulations on the multi-shell target ignition driven by radiation pulse in Z-pinch dynamic hohlraum*
Authors: Chen Shi-Jia , Ma Yan-Yun , Wu Fu-Yuan , Yang Xiao-Hu , Yuan Yun , Cui Ye , Cui Ye , Ramis Rafael
Published: May 2021

We present the first simulation results of a multi-shell target ignition driven by Z-pinch dynamic hohlraum radiation pulse. The radiation pulse is produced with a special Z-pinch dynamic hohlraum configuration, where the hohlraum is composed of a single metal liner, a low-Z plastic foam, and a high-Z metallic foam. The implosion dynamics of a hohlraum and a multi-shell target are investigated separately by the one-dimensional code MULTI-IFE. When the peak drive current is 50 MA, simulations suggest that an x-ray pulse with nearly constant radiation temperature (∼ 310 eV) and a duration about 9 ns can be obtained. A small multi-shell target with a radius of 1.35 mm driven by this radiation pulse is able to achieve volumetric ignition with an energy gain (G) about 6.19, where G is the ratio of the yield to the absorbed radiation. Through this research, we better understand the effects of non-uniformities and hydrodynamics instabilities in Z-pinch dynamic hohlraum.
Electrochemical safety limits for clinical stimulation investigated using depth and strip electrodes in the pig brain
Authors: Vatsyayan Ritwik , Cleary Daniel , Martin Joel R , Halgren Eric , Dayeh Shadi A
Published: May 2021

Objective. Diagnostic and therapeutic electrical stimulation are increasingly utilized with the rise of neuromodulation devices. However, systematic investigations that depict the practical clinical stimulation paradigms (bipolar, two-electrode configuration) to determine the safety limits are currently lacking. Further, safe charge densities that were classically determined from conical sharp electrodes are generalized for cylindrical (depth) and flat (surface grid) electrodes completely ignoring geometric factors that govern current spreading and trajectories in tissue. Approach. This work reports the first investigations comparing stimulation limits for clinically used electrodes in two mediums: in benchtop experiments in saline and in vivo in a single acute experiment in the pig brain. We experimentally determine the geometric factors, the water electrolysis windows, and the current safety limits from voltage transients, for the sEEG, depth and surface strip electrodes in both mediums. Using four-electrode and three-electrode configuration measurements and comprehensive circuit models that accurately depict our measurements, we delineate the various elements of the stimulation medium, including the tissue-electrode interface impedance spectra, the medium impedance and the bias-dependent change in the interface impedance as a function of stimulation parameters. Main results. The results of our systematics studies suggest that safe currents in clinical bipolar stimulation determined in vivo can be as much as 24 times smaller than those determined from benchtop experiments (for depth electrodes at a 1 ms pulse duration). Our detailed circuit modeling attributes this drastic difference in safe limits to the greatly dissimilar electrode/tissue and electrode/saline impedances. Significance. We established the electrochemical safety limits for commonly used clinical electrodes in vivo and revealed by detailied electrochemical modeling how they differ from benchtop evaluation. We argue that electrochemical limits and currents are unique for each electrode, should be measured in vivo according to the protocols established in this work, and should be accounted for while setting the stimulation parameters for clinical applications including for chronic applications.
Adjustable capillary imbibition enhancement in double-walled nanotubes with concentric tube length difference
Authors: Lu Yangchao , Wang Yangjie , Chen Jige
Published: May 2021

Capillary imbibition of water plays a significant role in various applications at both the macroscopic and microscopic scales. However, it is still unclear whether capillary imbibition could be manipulated by the geometry structure of the nanotubes. In this paper, we adjust the concentric tube length difference ∆L of the double-walled nanotubes (DWNTs) to manipulate the capillary imbibition by molecular dynamics simulations. Three configurations are considered, i.e. ∆L = 0 (the common DWNT structure, labeled as configuration I), ∆L < 0 (configuration II, the inner tube is shorter than the outer tube), and ∆L > 0 (configuration III, the inner tube is longer than the outer tube). By comparing with the single-walled nanotube, it is found that the imbibition velocities of the water molecules in the DWNT are weakened 9.1% in configuration I and enhanced 30%–46.5% in configuration II and 10% in configuration III. By analyzing the microscopic structure of the water molecules, it is found that the imbibition velocity adjustment originates from the potential energy difference of the water molecules in the water reservoir and at the entrance of the nanotube at the nanotube cylindrical pore. An exponential relation between the imbibition velocity v

L
and the potential energy difference ΔE is obtained as

v

L

(

t

)

∼

e

−

Δ
E

k

B

T

. Furthermore, it is found that imbibition velocity is independent from the radius differences in all three configurations. Our results suggest a possible way to manipulate the capillary imbibition behavior and it has significant implications for water treatment, nano-switches, catalysis engines and biological sensors.
Modified spectral method for optimal estimation in linear continuous-time stochastic systems
Authors: Rybakov K
Published: May 2021

The spectral method to solve estimation problems for linear continuous-time stochastic systems with polynomial measurements is presented. It is based on both the spectral form of mathematical description (the representation of deterministic functions and random processes by orthogonal series) and the particle filter. The main goal of this work is to implement the continuous-time particle filter without a time discretization. The proposed spectral method provides the possibility to solve estimation problems such as filtering, smoothing and prediction.
Combined system for indeterminate non-affine plant with control delay on the set of functioning states
Authors: Eremin E. L. , Nikifororva L. V. , Shelenok E. A.
Published: May 2021

In the present paper authors consider the synthesis of combined nonlinear control law for non-affine control plant with delay in the input variable with step-by-step changing of its dynamics. The control plant operates in conditions of a priori parametric and structural uncertainties in the presence of external noise and measurement of the controlled variable only. The structure of the control system includes the predictor-compensator and the filter-corrector.
Approximate methods of the solution of an optimal control problem on an operators network
Authors: Baturin V.A. , Sizykh V.N.
Published: May 2021

The mathematical models describing behaviour of an operators network, and in particular multi-stage processes, are quite common in practice. In this work, the authors propose approximate methods for solving the control problem with parameters on the network of operators. They are based on the methodology developed in works [1-4].
Technique for classifying the social network profiles according to the psychological scales based on machine learning methods
Authors: Branitskiy A. , Doynikova E. , Kotenko I.
Published: May 2021

A technique for classifying the social network users and groups by psychological scales of the Ammon’s test has been developed. To analyze user profiles, we have used several types of artificial neural networks (support vector machine, linear regression, multilayer neural network and convolutional neural network), and for group analysis, we applied text classifiers (bag of words, weighted bag of words, continuous bag of words, skip-gram and fastText classifier). The scope of the technique is identifying deviations in the psychological state of users of social networks and monitoring these changes considering users’ groups to detect destructive influences. An experiment was carried out, as a result of which it was found that a multilayer neural network with an activation function of the ReLU type has the best accuracy.
Optimization of the interplanetary flight to Mars with three-pulse approach to Phobos based on Lagrange principle
Authors: Samokhin A.S. , Samokhina M.A.
Published: May 2021

The problem of optimal control of the spacecraft interplanetary flight from the Earth to Mars with a three-pulse approach to the Phobos tracking orbit is considered. The departure of the spacecraft from the Earth is also approximated by pulses. The attraction of the Earth and Mars is taken into account. The problem is solved numerically on the basis of Lagrange principle. The results are compared with the scheme of a full turn free approach to Phobos. The initial approximation is carried out based on a combination of Lambert problems solutions. The software package is developed. Ephemerides are taken into account in the calculations, and the NASA SPICE package is used.
Intelligent system for data analysis and decision-making on test results
Authors: Saitova G.A. , Elizarova A.V.
Published: May 2021

Intelligent data analysis systems are designed to minimize the efforts of a decision-maker in the process of data analysis. The article deals with the tasks of intelligent processing and analysis of data from an electronic engine control system unit during testing. An intelligent data analysis system is proposed with the subsequent decision-making on the states of the engine and the electronic control system during test flights. With the help of artificial intelligence methods, causal relationships and regularities of the parameters of a turbojet engine have been revealed.
Results of computer simulation of force impact of difficult marine conditions on underwater objects
Authors: Guryev Y. V. , Slutskaya M. Z.
Published: May 2021

The paper presents a numerical method for calculating the hydrostatic and hydrodynamic reactions of marine underwater objects moving in an arbitrary manner under conditions of internal waves and sea currents. The method is based on the theory of potential, eddy and wave currents. The effect of viscosity on hydrodynamic reactions is taken into account indirectly by introducing a special eddying system that simulates the effect of longitudinal vortices on the hull on the pressure distribution. The paper presents the results of a computational experiment are presented, which made it possible to identify both new and confirm previously obtained regularities of the influence of the object’s parameters and hydrophysical conditions on the desired reactions. The developed mathematical and software tool can be recommended for use in the design of underwater objects and the creation of simulators for their dynamics.
Universal pause of the human-perceived winter warming in the 21st century over China
Authors: Ding Ting , Gao Hui , Li Xiang
Published: May 2021

Low-temperature weather accompanied by strong chill wind is considered as a great risk factor for human health in winter, especially in some extreme weather conditions. Based on the observation data and the NCEP/NCAR reanalysis data of air temperature and wind velocity in 1961–2019, the warming pause of wind chill temperature (WCT) in the 21st century in China is first revealed in this paper. A significant increasing trend of WCT is found during 1961–1999 (P1), and a slight decreasing trend in 1999–2019 (P2) is detected by a 21 year running trend analysis. The extreme cold WCT day (WCD) with the WCT index below the 10th percentile also shows a decreasing trend in P1 but a slight increasing trend in P2. Both the WCT and the extreme WCD consistently display the warming pause in seven climatic regions in China. That means the slowdown or even decrease of human bioclimatic temperature in recent two decades may lead to an increasing risk of frostbite and other cold-related diseases in the country. Both the decreasing trend of mean temperature and the increasing trend of the wind speed contribute to the slowdown of the human-perceived warming in the 21st century, and this conjoint contribution could be linked to the East Asian winter monsoon circulations over Siberia, i.e. the Siberian high. The variation of averaged sea level pressure over the central region of the Siberian high shows high consistency with both the WCT and the extreme WCD in the whole study period, by a decreasing rate of −1.28 hPa per decade in P1 and an increasing rate of 1.26 hPa per decade in P2.
Smart Trowel Tool for Smooth Plastering Work
Authors: Doraisamy S V
Published: May 2021

Plastering is the most important activity in construction works. It is done widely as a finishing technology for interior and exterior walls made of bricks, concrete or timber, as it provides heat insulation, sound absorption and protection against air pollution and weather, thus providing a clean, level surface for further finishing tasks. Plastering work usually consumes time and involves a lot of cement wastage. A trowel is used as a tool in plastering work but yet time consumption is high in completing the work. It is because the design of the trowels and the quality of the trowel itself is not suitable for plasterers. This study focuses on designing a smart trowel tool for smooth plastering work for low-cost residential building, and to compare the time consumption for the smart trowel tool with the conventional method. The smart trowel tool was tested with 4 experts from the construction industry at the end. The main aspect that was taken into consideration in determining the most suitable materials to build this tool was the time factor in conducting and completing the plastering works. The feedbacks given through expert validation was positive and suggested that such a tool should be marketed in the related field. This is mainly because the smart trowel tool that was build tends to give comfortability and convenience to its’ users. The tool further plays the role of as environmentally friendly that contributes towards sustainability. Lastly, the smart trowel tool consumes lesser time compared to the conventional method.
Physical and mechanical properties of cement board made from oil palm empty fruit bunch fibre: A review
Authors: Maynet W , Samsudin E M , Soh N M Z Nik
Published: May 2021

Oil palm empty fruit bunch (OPEFB) fibre has been introduced to replace current materials mainly such as wood fibre that was not encouraged to be used as a construction sourced due to the sustainability of wood fibres and prevents the high demand of forest resources. In Malaysia, the cultivation and use of the oil palm and its products have increased because of high market demand, and this has resulted in the abundant availability of the empty fruit bunch (EFB). The EFB fibre geometry and particle size in the EFB cement bonded boards have their own mechanical and physical properties. The fibre to cement ratios are also different to boards made out of wood fibres. This experimental research work has been conducted by other researchers. The larger the particle size, the better the compaction of EFB-CB effects of cement setting by much larger surface on the board area. Short particles lead to low values of modulus of elasticity (MOE), caused by inadequate of empty fruit bunch (EFB) particles to cement substances. Nevertheless, short particles avoid large void spaces and irregularities towards cement board. Using different Cement-EFB fibre ratio has direct influence on thickness swelling (TS), modulus of rupture (MOR), and modulus of elasticity (MOE). Strength of EFB-CB depends on the bonding between fibre and cement composites. The pre-treatment fibre was indicated where the EFB fibre composite were dimensionally stable for bonding mechanisms and could be used for both interior and exterior building utilizations based on the tested physical and mechanical properties on cement-boards.
Structural behaviour of PSCC slab panel under four-point bending test
Authors: Iman M A , Mohamad N , Samad A A A , George Steafenie , Tambichik M A , Bosro M Z M
Published: May 2021

Precast Self-Compacting Concrete (PSCC) is one of many types of approach in Industrialised Building System (IBS) that were used to speed up construction to meet consumer’s demand. The usage of Self-Compacting Concrete (SCC) will profit in many ways such as faster construction, reduction in manpower, easier placing, uniform and complete consolidation, better surface finishes, improved durability, increased strength, and safer working environment. The addition coir fibre in PSCC can improve the tensile strength and flexural strength in the concrete mixture.by combining the two elements of SCC and CF in PSCC slab panel, the desired structural behaviour can be achieved. The four-point bending test was conducted on the all 4 type of PSCC slab panel that is solid control, solid CF, hollow control, and hollow CF. The solid PSCC-CF slab panel has the best structural performance compared to the other 3 other PSCC slab panel. The crack and ultimate load of the solid PSCC-CF slab panel recorded are 24.5 kN and 35 kN respectively compared to the reading collected from the other 3 slab panels. The crack propagation on the solid PSCC-CF slab panel also less propagated due to the addiction of CF that build concrete bridges. The load-deflection profile of solid PSCC-CF slab panel also shown the best result compared to the other slab panel. The load-strain profile recorded also shown the highest values of 105 micro strain on top and 53.14 micro strain on side of solid PSCC-CF slab panel.
Strength Performance of Oil Palm Shell Lightweight Aggregate Concrete
Authors: Jamellodin Zalipah , Sim Lam Phooi , Qing Huang Chai , Adnan Suraya Hani , Salleh Norhafizah , Hamid Noor Azlina Abdul
Published: May 2021

The concrete consumption that is high in the construction industry had resulted in uncontrolled aggregates exploitation. The extraction of these natural resources has raised great environment concerns that the use of waste materials as replacement of aggregates is proposed. Oil palm shell lightweight aggregate concrete (OPS LWAC) is produced by full replacement of oil palm shell (OPS) to coarse aggregate. OPS is the lightweight aggregates that potentially produce lightweight aggregate concrete (LWAC). Palm oil fuel ash (POFA) is also the byproduct of the palm oil industry that can be utilized to partially replace the fine aggregates. The objective of this study is to investigate the effect of POFA as partial fine aggregates replacement on density, compressive and tensile strength of OPS LWAC and to determine the optimum replacement percentage of fine aggregates with POFA. The control mixes were prepared with 100% OPC in the concrete while modified mixes contained various percentages of POFA, which were 5%, 10%, 15% and 20% as the replacement of fine aggregate. The specimens of cubes sizes 100 mm x 100 mm x 100 mm and cylindrical specimens with diameter of 100 mm and height of 200 mm were prepared and tested. The concrete mixtures were mixed according to the Department of Environment (DoE) method followed by the trial mixed. Mixes with 10% replacement of POFA to fine aggregate obtained the highest compressive strength and tensile splitting tensile strength which were 26.3 MPa and 2.37 MPa respectively. The property of POFA plays a role in the concrete strength determination. The higher replacement percentages resulted in lower density of OPS LWAC.
Utilization of Fruit Wastes (Jackfruit and Mango Seeds and Banana Trunk) as Natural Coagulants in Treating Municipal Wastewater
Authors: Shahimi Nur Shahzaiwa Wafa , Zaidi Nur Syamimi , Bahrodin Muhammad Burhanuddin , Amran Amir Hariz
Published: May 2021

The adequacy of chemical coagulant such as alum is all around perceived. However, there are numerous drawbacks including impeding impacts on human well-being and generation of high sludge volumes. Therefore, this study was conducted to investigate potential of fruit wastes - jackfruit (artocarpus heterophyllus) seeds, banana trunk peduncles (musa) and mango (mangifera indica) seeds in becoming natural coagulant to treat wastewater. A series of jar test was performed to determine the effect of individual coagulants on turbidity removal, coagulation activity and COD removal under various operating factors such as type and concentration of solvents used for extraction, pH and coagulant dosage. From the findings, optimum solvent concentration of 2.5M of sodium hydroxide (NaOH) reacted with banana trunk peduncles at optimum pH and dosage of pH 7 and 50 mg/L, respectively with turbidity removal of 90.2%, coagulation activity of 83.4% and chemical oxygen demand (COD) removal of 94.8%.
Physical Simulation for Effect Seasons and Fertilizer on Solidified Fabric Peat Soil; A Soil Column Model Study
Authors: Tajuddin S A M , Rahman J A , Mohamed R M S R , Al-Gheethi A
Published: May 2021

Soil stabilization is a method to improve the weakness of fabric peat soil structure which is a result of larger particle size pore. Therefore, the fabric peat soil is solidified using mixture of cement, fly ash and bottom. The present study aimed to investigate a physical simulation of soil column model as a response for affecting the wet and dry seasons and fertilizer on the solidified fabric peat soil. The column mode was investigated by analysis the water leaching micronutrient using atomic adsorption spectroscopy (AAS). The results revealed that the nitrate has the highest concentration (35.55 mg/L) on Run 3 (Fibric, rainwater, solidified peat and fertilizer) at upper area in the dry season. In comparison, potassium (K) recorded the lowest concentrations (1.14 mg / L) on Run 2 (fibric, rainwater and fertilizer) at upper area in the wet season. The highest (22.92 mg/L) and lowest (0.10 mg/L) calcium was recorded on Run 3 and Run 2 with both at upper area in wet season. These findings indicated that the chemical binder used as stabilization soil influenced the nutrient quality especially calcium which is one of the major compound materials in cement.
A Column Study on The Efficiency and Reusability of Kapok Fibre as Car Wash Wastewater Treatment
Authors: Hashim N H , Chen W C , Ibrahim M S S , Abdullah N M , Abdullah Z
Published: May 2021

The car washing industry which consumes large amount of water produces Car Wash Wastewater (CWW) which were likely to exceeds the standard set in both Malaysia’s and Singapore’s regulation. Kapok Fibre (KF) is a natural adsorbing material which have large lumen and low density is believed to be able to act as an adsorbent to manage the CWW. This study was done to determine the characteristic of KF and CWW and investigate the efficiency of KF in treating CWW along with the reusability of KF through a column study with Organic Loading Rate (OLR) of 12.41g COD/L.day. The CWW contains a certain concentration of Chemical Oxygen Demand (COD, Oil and Grease (O&G), and Anionic Surfactant (AS) though the interaction between KF and AS is novel. KF found out to has the capability in removing COD, O&G, and AS up to 88.37%, 100%, and 83.8% respectively. However, in reusability experiment there is limitation to KF in which by exceeding the operation time to 600 minutes of treatment, the efficiency in removing COD, O&G, and AS were found to drop to 62.02%, 75%, and 55% respectively. This shows that KF could be an avant-garde, low-cost sustainable treatment to treat CWW instead of the conventional high cost and complex operating system.
Correlation between Pump Discharge and Operational Cost of Polder System: Case Study of Pekalongan Regency
Authors: Susanto Deddy , Wahyudi Slamet Imam , Niam M Faiqun
Published: May 2021

The coastal area in Pekalongan has a big problem of flood that is caused by rain and tidal flood. To overcome the situation, in 2018-2019, a drainage with polder system has been built at Mrican-Wonokerto area, Pekalongan Regency, equipped with the 5 km embankment and long storage. The aim of this study was to acquire correlation model between pump discharge and fuel oil consumption of Mrican-Wonokerto Polder System and to conduct simulation of operational cost from the fuel oil to the electricity provided by PLN. The method used is quantitative method with daily data in the form of pump operation record of Silempeng and Sengkarang pump houses. The analysis results indicated that the equation of the relation between the pumping volume capacity (X) (in m3) and fuel oil consumption (Y) (in liter) of Silempeng and Sengkareng pump house were linear equations. The equations were Y = 0.2509+ 0.0044X with a correlation coefficient (r) of 0.928 for Silempeng and Y = 0.5608+0.0035X with r=0.981 for Sengkarang. The equation of relation between the actual pumping volume and and fuel oil consumption during the absent of rain was Y=0.5292+0.0067X with r=0.8328, while the rainy days was Y= 0.6605+0.005X with r=0.8329. The simulation of change from propulsion of diesel pump machine to electric propultion proofed that the change could generate efficiency 45.12% at Silempeng and 30.53% at Sengkarang pump house in the aspect of operational cost. The results of this study are used to a guidance for pump operational financing by the government.