bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization-based calibration of hydrodynamic drag coefficients for a semisubmersible platform using experimental data of an irregular sea state
Authors: Böhm M , Robertson A , Hübler C , Rolfes R , Schaumann P 
Published: October 2020

Abstract
For the simulation of the coupled dynamic response of floating offshore wind turbines, it is crucial to calibrate the hydrodynamic damping with experimental data. The aim of this work is to find a set of hydrodynamic drag coefficients for the semisubmersible platform of the Offshore Code Comparison Collaboration, Continuation, with Correlation and unCertainity (OC6) project which provides suitable results for an irregular sea state. Due to the complex interaction of several degrees of freedom (DOF), it is common to calibrate drag coefficients with the time series of decay tests. However, applying these drag coefficients for the simulation of an irregular sea state results in misprediction of the motions. By using numerical optimization, it is possible to calibrate multiple drag coefficients simultaneously and effectively, while also considering several DOF. This work considers time series of structural displacements from wave tank tests of the OC6 project and from simulations of the same load cases in OpenFAST. Results are transferred into the frequency domain and the deviation between power spectral densities of surge, pitch and heave from experiment and numerical simulation is used as an objective function to obtain the best fitting drag coefficients. This novel numerical optimization approach enables finding one set of drag coefficients for different load cases, which is a major improvement compared to decay-test-tuned drag coefficients.
Dependence of Floating LiDAR performance on external parameters – Are existing onshore classification methods applicable?
Authors: Wolken-Möhlmann Gerrit , Gottschall Julia 
Published: October 2020

Abstract
Floating LiDAR is a new aspiring technology for replacing offshore meteorological masts for applications like offshore site assessment or power curve measurement. Since the beginning of the development of the first Floating LiDAR Systems (FLS) in the late 2000s, the systems are more and more maturing. The focus of current research is moving from the pure technology development to the application of the obtained data. As a result, procedures for assuring the measurement quality and the assessment of the data quality - or the quantification of estimated measurement uncertainty, respectively - is a key aspect for further increasing the confidence in the data. This is an important pillar for a further distribution of the technology, and for decreasing risks and costs for its application in offshore wind.
In this paper, we introduce the methodologies of FLS verification and classification, with the goal to verify the measurement of individual FLS and study the characteristics of a certain type of LiDAR systems. A classification case study is presented, showing low effects of the buoy motion and sea states on the FLS measurement for the Fraunhofer LiDAR buoy. A detailed study of the interdependencies between influencing parameters and the possible correlations is presented as well.
The robustness and issues of the classification methodology - originally defined for fixed LiDAR systems - is discussed. Especially the non-robustness of the bin-fitting is identified as an issue. Alternative methods for the sensitivity analysis within the classification process are discussed.
A study of radiation tolerance in optical cements
Authors: Tesarek R.J. , Hahn E. , Pla-Dalmau A. , Jr. J.L. Salinas , Wenzl D. 
Published: October 2020

We study the effect ionizing radiation has on light transmission in the wavelength range 190–1100 nm for a number of optically clear epoxies. We find that the transmittance of traditional, commercially available, optical epoxies show significant degradation for exposures of 1×1012MIPs/cm2. Degradation of light transmission progresses from the shortest wavelengths at low doses to longer wavelengths as the dose increases. In epoxy joints that are 0.1 mm thick, we observe that more than 5% of the light is lost for wavelengths less than 400 nm for traditional optical epoxies. Our studies have identified an optically clear epoxy that shows little degradation for radiation exposures up to 5.9× 1014MIPs/cm2(≈ 220 kGy).
Impacts of urbanization, antecedent rainfall event, and cyclone tracks on extreme floods at Houston reservoirs during Hurricane Harvey
Authors: Li Xudong , Zhao Gang , Nielsen-Gammon John , Salazar Joel , Wigmosta Mark , Sun Ning , Judi David , Gao Huilin 
Published: October 2020

Abstract
The objective of this study is to evaluate the effects of urbanization, an antecedent rainfall event (ARE), and varying cyclone tracks on the streamflow—and thus the subsequent reservoir status—during the floods caused by Hurricane Harvey in August–September 2017. Through a hydrological modeling approach, we examined how these factors influenced the inflows, peak pool elevations, and outflows of the two most important detention reservoirs in the Houston region, the Addicks and Barker Reservoirs. A high-resolution rainfall reanalysis dataset for extreme storm events, along with a suite of synthetic rainfall values from a variety of storm tracks, were adopted to represent both the truth and the maximum possible rainfall during the Hurricane Harvey period. The results showed the following: Urbanization only led to slight increases in peak inflows, not necessarily to an increase in peak pool elevations, and the ARE contributed to the peak inflow and pool elevation slightly. In contrast, if the cyclone had followed the most adverse track consistent with earlier forecasts (all else being equal), the total volumetric flow into the two reservoirs would have been significantly larger (37% and 49% respectively), thus increasing the peak pool elevations by 1.06 and 1.37 m respectively. These results suggest that large uncertainties exist for flood management at a watershed scale during hurricanes, because of the uncertainties in the cyclone track. This would remain true even if storm-relative precipitation rates could be predicted perfectly.
Determination of thermal parameters of a shell and tube heat exchanger with increased turbulization of the working fluid
Authors: Nikulin N Yu , Kushchev L A , Feoktistov A Yu 
Published: October 2020

Abstract
Shell and tube heat exchangers are still widely used. This equipment is widely used in heat supply systems, food, chemical and petroleum industries. Therefore, conducting research to improve their performance is an important area. By changing the geometry of the heat exchange surface, the flow of the working fluid is further turbulated and the heat exchange area increases. The heat exchanger with a developed heat exchange surface is proposed, which differs from the serial device (with smooth tubes). Thus, a plate equipped with a cylindrical edge is installed on the heat exchange tube. The working fluid in the inter-tube space, flowing around the edges, is turbulated. This reduces the thickness of the laminar sublayer on the plate and edge. Accordingly, the heat transfer from the heat exchange surface to the streamlined fluid increases. When new elements appear in the design of the heat exchange surface, it is necessary to develop the calculation of temperature parameters for these surfaces. Formulas for calculating the average surface temperature of the edge and plate under conditions of turbulent flow around these surfaces are obtained analytically. The temperatures of the plate and edge will determine the Prandtl criterion Pr. In the future, this is necessary to find the main parameter of the heat exchanger – the heat transfer coefficient.
Simulation of accelerated concrete destruction by inoculation of an association of bacteria of the genus Thiobacillus
Authors: Fomina E V , Sverguzova S V , Goncharova E N , Flores-Vivián I 
Published: October 2020

Abstract
The mechanisms of biogenic destruction of concrete under the influence of microbiological corrosion are described. An accelerated method of inoculation of the association of sulfur-oxidizing thionic bacteria Thiobacillus thioparus and Thiobacillus thiooxidans was used. Beyerink solution was used as a nutrient medium. The impact of two types of microorganisms in model systems imitates microbiocorrosion conditions; this allows reducing the test time and predicting the mechanisms of concrete destruction during operation. The active development of Thiobacilus thioparus promotes the leaching of concrete, further bacteria of the genus Thiobacilus thiooxidans appear with a decrease in pH, and both species actively synthesize sulfuric acid. The kinetics of the bio corrosion process was monitored for 60 days. The bacterial adaptation period is 16–18 days, after which the pH of the aqueous medium decreases. The rate of formation of a biological acid in an aqueous medium determines the leaching of Mg2+, Ca2+, and

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4

2
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ions from concrete. Concrete when exposed to bio acids for two months loses 30% of its strength. The microstructure analysis of bio corrosion products on the concrete surface was carried out with the help of a scanning electron microscope.
Finishing materials in construction using polymer composites
Authors: Klyuchnikova N V , Klepikova M A , Denisova L V 
Published: October 2020

Abstract
Polymer composite materials are increasingly replacing traditional composites such as wood, metal, and natural fibers from the world market of building materials. Polymer composite materials are widely used in the construction industry. Currently, the development of advanced polymer-based composites is a very relevant area. The promising method for modification of epoxy polymer composite with mineral filler schungite is considered. It was found that the introduction of mineral filler increases the composite resistance to impact forces. It is proved that schungite-filled epoxy composites have increased strength and performance properties, which is very important when they are used in the construction industry. After carrying out a number of physical, mechanical and operational studies, it can be concluded that polymer composite materials based on ED-20 resin with the content of mineral filler shungite have the best performance, compared to non-filled composite materials. Thus, the resulting PCM can be used in the construction industry as a finishing material, as it has the necessary complex of strength and performance properties.
Obtaining sorption material from sorghum for aqueous solutions purification from heavy metals
Authors: Fomina E V , Sverguzova S V , Sapronova ZH A , Kozhukhova M I 
Published: October 2020

Abstract
The paper presents the results of using straw (stalks) of sorghum as a sorbent for removing heavy metal ions of Cu (II) from aqueous solutions. The physical and chemical analysis of sorghum has been carried out. The modification of plant materials by exposure to a temperature of 130-150 ° C is proposed. Thermal activation allows obtaining a highly developed surface of the sorghum microstructure and increasing the total pore volume and their average diameter. The regularities of the effect of the concentration of the modified sorbent and the differences of its dispersed particles on the efficiency of water purification are investigated. The purification of an aqueous solution containing 50 mg/dm3 of Cu2+ ions was 95% under using a thermo-treated sorghum of 0.63–0.1 mm in an amount of 2.5 g per 100 ml of an aqueous solution. Thermal modification of sorghum allows you to get an effective sorbent and immediately solve two environmental problems, such as wastewater treatment and utilization of plant waste.
Sustainability of functioning of enterprises of the building materials industry of the Belgorod region in 2018-2019
Authors: Slabinskaya I A , Benderskaya O B 
Published: October 2020

Abstract
Ensuring the sustainability of functioning under all changes in the economic situation in Russia and in the world continues to be one of the most important goals of managing an enterprise in any sector of the real sector of the economy. This article investigates the stability of the functioning of a sample of the most famous enterprises in the construction materials industry of the Belgorod region: OAO Belgorodasbestocement, ZAO Belgorodskij cement, OAO Belgorodstrojdetal’, OAO Zavod ZHBK-1 and AO Strojmaterialy, using the author’s methods for assessing the stability of functioning. The study period is 2018-2019. The informational basis of the study is the public financial statements of enterprises for 2019. The assessment methodology is based on a system of 12 indicators-indicators of the stability of functioning. For a comparative intercompany assessment of enterprises, the author’s method of calculating a comprehensive assessment was used – a modified method of scoring. Based on the obtained values of comprehensive assessments, stability ratings for the functioning of enterprises for 2018 and for 2019 are compiled.
Investigation of stresses and deformations of ball mill support axles taking into account the temperature field by numerical method
Authors: Bondarenko J A , Duyun T A , Bestuzheva O V 
Published: October 2020

Abstract
In the article, the stresses and deformations of the ball mill support axes are studied numerically, taking into account the temperature field. Expressions are given that determine the values of the stress-strain state of the external surface of the ball mill trunnion, depending on the temperature of the internal and external surfaces. The analysis of the behavior of stresses and deformations when changing the temperature parameters of the trunnion is based on the numerical method. Constant values and parameters of the trunnion are set, and the temperature ranges of the external and internal surfaces of the loading and unloading trunnions are set. A numerical simulation of deformations and stresses is presented, described in the form of dependency graphs with varying parameters-the temperature of the internal and external surface of the trunnion within specified limits. The dependences of stresses and deformations of the external surface on temperature changes are analyzed. It is shown that as the temperature difference increases, the stresses in both the circumferential and axial directions increase, and the deformations in the circumferential and axial directions monotonously increase. The unloading axle is subject to a more complex stress-strain state under the influence of a temperature field, and the external surface of the axle has the highest values of stresses and deformations.
Management mechanisms for resolving organizational conflicts in the context of implementing the economic opportunities of organizations in the construction industry
Authors: Tselyutina T V , Avilova Zh N , Timokhina O A 
Published: October 2020

Abstract
The paper presents a critical analysis of the functional representation of the mechanism for managing social and labor conflicts in the process of organizational changes. Network mechanisms and their functionality in the management system of organizational conflicts are updated. The relationship between the level of staff involvement in work and the level of conflict in the organization is determined. To ensure effective management of organizational conflicts, it is necessary to take into account the level of involvement of the personnel of the organization in processes at different levels, as well as to create conditions and economic methods of motivation that ensure the necessary level of involvement. “Portfolio” of empirical tools for comprehensive research of issues and a mechanism for managing organizational conflicts are developed, taking into account the specifics of the activities of construction organizations.
Portland cement foam concrete with a zeolite-containing mineral additive
Authors: Rozhin V N 
Published: October 2020

Abstract
The possibility of obtaining high-quality cement by an environmentally friendly (without CO2 emission into the atmosphere) method of joint grinding of imported Portland cement clinker and local natural mineral raw materials in hard-to-reach areas of the North-East of the Russian Federation is substantiated. The results of an experimental study of the compositions and technological parameters of the manufacture of cement compositions based on portland cement clinker and active mineral additives from zeolite-containing rocks of Khonguruu, allowing non-autoclaved foam concrete with a density of 600-800 kg / m3 and compressive strength of 1,8-2,8 MPa with stable quality parameters are presented (monodisperse pore distribution and hardened inter-pore skeleton, providing stable values of density, strength and thermal conductivity).
Dynamic test method for full body harnesses exploited in cold climates
Authors: Dmitry Prostakishin , Pham Nam Thanh 
Published: October 2020

Abstract
In this paper, a method of testing the dynamic strength of full body harnesses is proposed. The possibility of conducting the method in laboratory conditions is determined by testing the method while maintaining the specified conditions of low temperatures. The main attention is paid to the effect of the set temperature on the full body harnesses, when dynamic shock loads occur in user operation mode. The advantage of the developed method of dynamic testing of full body harnesses is the simplicity in bringing the test sample to the climatic parameters of operation by pre-conditioning. This makes it possible to implement dynamic testing under specified climatic conditions within mass laboratories in the chain of conformity confirmation. Pre-conditioning allows you to conduct research on the influence of climate factors on various characteristics of safety harnesses. The interaction of the binding elements with each other, previously reduced to the specified temperature parameters, is also studied. It is necessary to pay special attention to the resulting impact loads during dynamic tests, and their relationship when conditioning products at different temperature.
Mixing process simulation of the initial building materials components using the DEM Solution EDEM system
Authors: Samsonova P S , Lozovaya S Y , Bogdanov N E , Lozovoi N M 
Published: October 2020

Abstract
Quality of building materials, products and constructions depends on the organization of technological process of their production, and it, as a rule, concerns preparatory operations, such as crushing and in a greater degree mixing of initial compound components of the future products and constructions. Production of high-quality building mixtures is one of the most actual tasks of modern building technologies. Today, the mixing of bulk materials has evolved into a special branch of technological knowledge, which is based on mechanical processes, whose goal is to ensure the highest possible degree of alignment of individual components in the mixture. Due to the development of digital technology, modern industry is able to abandon expensive and long field experiments and tests in favor of digital experiments. The results of digital experiments have a high degree of convergence with real experiments, but are carried out many times faster. To model the influence of the material loading method on the heterogeneity factor of the mixture, digital sampling was carried out using EDEM software in a screw type mixer.
Impact of a pump unit and geothermal pump use on soil condition
Authors: Orlov K P , Orlova V A , Kupriyanov S V , Bojkov Y N 
Published: October 2020

Abstract
The article considers the advantages of air heat pump use. Their positive impact on ecology compared to other types of similar pumps, in particular geothermal ones, is shown. The author aims to focus on the problems of gross interference with the soil structure. In the majority of sources, geothermal pumps are presented as environmentally friendly and recommended pumps. The task of the study is to prove analytically, as well as using general scientific methods, that these sources are wrong. The use of geothermal heat pumps causes damage to the environment, since well drilling in the vast majority of cases is followed by formation segregation, interstratal insulation violation, change in natural processes of water bodies self-purification, rate of mineralization flow, kinetics of microflora and fauna development and die-away. Significant areas of uninhabitable trees and plants are formed due to subsoil cooling and freezing. Various heat pump layouts were analyzed and conclusion on the most environmentally friendly integrated use of heat air pump and solar energy was made.
Dynamic stress-strain state of earth dam considering an inhomogeneous base
Authors: Salyamova K D 
Published: October 2020

Abstract
The design, construction and operation of important water retaining structures (high earth dams) in seismic regions, such as the territory of the Republic of Uzbekistan, require constant improvement of the methods to calculate their behavior under various loads, including seismic ones. A variational statement of the problem of natural vibrations of a plane elastic earth dam with and without an adjacent base is given. The problem is solved numerically by the finite element method. The aim of this study is to determine the effect of a piecewise-inhomogeneous section at the base of an earth dam on the stress-strain state of the dam itself. The result of solving the problem lies in the analysis of eigenfrequencies, vibration modes, stresses of a concrete earth dam.
Method for justification options for housing stock reconstruction
Authors: Biryukov Yu , Makarov R , Dobryshkin E 
Published: October 2020

Abstract
The main contradictions in the theory and practice of housing stock objects reconstruction are revealed. The technical condition of housing stock reconstruction facilities is analysed and a study of the organization and planning of housing stock reconstruction in the North-western federal district is performed. A method of substantiating options for reconstruction of housing stock in the North-Western federal district has been developed. Its practical significance lies in its application to justify the reconstruction option for technical re-equipment and modernization of housing facilities in Federal and municipal authorities implementing state policy in the field of providing the population with comfortable living conditions, as well as in regional departments of contractors, which perform housing facilities repair work, at the stage of design estimates development for the reconstruction of facilities. Thus, the purpose of the study (to improve the efficiency of planning the housing facilities reconstruction in the North-western federal district on the basis of the developed scientific and methodological apparatus) has been achieved.