bluuebunny/crossref_metadata_2025_split huggingface dataset:
Series of split silencers for ventilation systems
Authors: Plitsyna O V , Rogova T N 
Published: September 2020

Abstract
The paper is devoted to the prospects of noise reduction in ventilation systems with large cross-section main air ducts. The design schemes of a split silencer for various systems obtained as a result of calculations and experiments are proposed. For a silencer whose split ducts are formed by successive narrowings and expansions the parameters ensuring minimum noise reduction of 7.5 dB and pressure loss of up to 120 Pa are shown and the recommendations for usage in systems where two-phase flows propagate are given. For a silencer whose split ducts contain internal elements the parameters that provide a minimum noise reduction of 10 dB and pressure loss of up to 90 Pa are identified and the recommendation for usage in supply ventilation systems with the required disinfection is presented. For a silencer that combines two sections with oppositely oriented split ducts its applicability in systems without aerodynamic restrictions and with increased acoustic requirements was noted. For additional silencer section composed from Helmholtz split resonators the parameters that ensure even noise reduction are shown and the recommendation for usage in systems without restrictions on the length of the main duct and with increased low-frequency noise reducing requirements is given.
Improving special motor vehicle internal combustion engines to raise environmental safety
Authors: Kondratyuk A A , Evtyukov S A , Vorobev S A 
Published: September 2020

Abstract
The paper presents the results of theoretical and experimental studies of the environmental characteristics of internal combustion engines for commercial and public motor vehicles operating on the Diesel cycle using a hydrogen additive. An analysis of literary sources confirmed that there are different data on harmful emissions when using a hydrogen additive for internal combustion engines operating on the Diesel cycle. The results of theoretical and experimental studies of the environmental characteristics of internal combustion engines for commercial and public motor vehicles operating on the Diesel cycle using a hydrogen additive suggest the adequacy of the built model, since the error between the theoretical and experimental data did not exceed 14.5%. It was found that the concentration of NOx emissions in an internal combustion engine using a hydrogen additive operating on the Diesel cycle decreased by 52%. The above research results confirm the prospects for the use of hydrogen additive for internal combustion engines operating on the Diesel cycle, which was first used for commercial and municipal motor vehicles. It guarantees improved environmental safety in urban agglomerations.
Development of the non-destructive monitoring methods of the pavement conditions via artificial neural networks
Authors: Elshamy M M M , Tiraturyan A N , Uglova E V , Zakari M 
Published: September 2020

Abstract
Non-structural parameters like surface defects and ride quality were frequently used, as a practical index for the rehabilitation selection process. The key purpose of this study was the assessment of using artificial network technology as a support for decision-makers about paving maintenance concerning the structural condition compared to the conventional, time-consuming, effort, and costly methods. The structural model was established based on the deflections from the FWD, (asphalt and base) layers thickness, surface temperature, precipitation rate, AADTT, traffic volume of class 9 and base layer type. The data used in building the developed ANN model is related to a previous study of flexible pavement structures on the M4 highway in the Russian highways network during the five years 2013-2017. The ANN model was built, trained, and tested by the Matlab program. The focus was on calculating roughness, fatigue, and rutting values as they are the most common pavement distress on site. We used the logistic model equations, developed by the Federal Highway Administration’s Long-Term pavement Performance (LTPP) to calculate the three pavement distress that will be used as output variables while training the ANN model. The ANN model presented a high performance in predicting the three pavement distress (fatigue, roughness, and rutting) where the R- squared value was equal (1, 0,999, and 1), respectively for the forecasting sections.
Conditions modelling of low-temperature cracks existence in the road upper layer
Authors: Gavrilov T , Kolesnikov G 
Published: September 2020

Abstract
Cracks, including low-temperature cracks, reduce to the greatest extent road surfaces quality, increase the cost their repair. This problem is most relevant in the regions with seasonal soil freezing. The purpose of this study is to develop a model of interaction between the asphalt concrete layer and the underlying layer by means of friction and adhesion forces at a negative temperature, also the analyze the conditions low-temperature cracks formation of in the asphalt concrete layer, in order to reduce the risk of cracking. Methods: as a research tool used numerical methods of structural mechanics. Results: the study found that the distribution of tensile forces in the segment of an asphalt-concrete layer is approximated by a polynomial of the second order with a maximum in the middle of the length of the segment. Shear forces are unevenly distributed along the length of the segment; the intensity of the shear forces is equal to zero in the middle of the length of the segment. The greatest shear strains and stresses are localized near the transverse boundaries of the segment of the layer. A shear deformation can lead to an increase in the crack width. The validity of the numerical simulation results is confirmed by their consistency with the known analytical solution of the same problem.
A new approach to thyristor-based converter commutation configuration for AC-wire DC-motor electric locomotive traction and energy regeneration modes
Authors: Vlasyevskiy S V , Malysheva O A , Melnichenko O V , Barinov I A , Boginskiy S A 
Published: September 2020

Abstract
The widespread use of power converters in modern electric locomotives provides multiple opportunities for railway electric transport, one of them being smooth supply voltage regulation. For electric locomotives with smooth voltage regulation the overall efficiency of energy consumption is dependent on power factor of its power converters, both in traction and regenerative braking modes. Power factor of thyristor-based converters universally used on Russian railways remains to be relatively low. The paper presents a technical proposal to modernize the type AC-wire DC-motor electric locomotive power circuit by introducing a semiconducting discharge shunt in parallel with the subcircuit of rectified current, which allows for a revision of the traditional control algorithm of the converter’s thyristor arms. Mathematical modelling of the proposed circuit suggests a 4.6 % increase in converter power factor in traction mode and an 18.5 % increase in regenerative braking mode under nominal load conditions.
Anderson transition in the cation-substituted compounds ReXMn1-XS
Authors: Kharkov A M , Sitnikov M N , Begisheva O B , Kretinin V V , Abdelbaki Hichem 
Published: September 2020

Abstract
The electrical properties of cation-substituted ReXMn1-XS (Re = Gd, Sm, Ho) compounds are investigated in the temperature range of 77-1200 K. A change in the type of conductivity from semiconductor to “metal” in ReXMn1-XS compounds at a critical concentration of Xc with an increase in the degree of cationic substitution is detected. The metal-dielectric concentration transition in the GdXMn1-XS system is accompanied by a decrease in the value of the specific electrical resistance by 12 orders of magnitude. For Sm0.2Mn0.8S, a sharp maximum of resistance is detected at T = 100 K, which can be caused by scattering of conduction electrons on spin fluctuations of localized electrons. The metal type of conductivity was established for Sm0.25Mn0.75S. In the HoXMn1-XS system, the Anderson transition was detected for XC = 0.3 with a decrease in the value of the specific electrical resistance by 10 orders of magnitude.
Factors influencing flexoelectric polarization in liquid crystals
Authors: Denisova O A 
Published: September 2020

Abstract
The work experimentally investigated the factors affecting the formation and physical parameters of flexoelectric polarization in liquid crystals (LC) with nematic as well as smectic A- and C-phases. Factors such as the heating temperature of the sample, orientation effects near the nematic – isotropic state (N-I) phase transition, and the initial orientation of LC molecules were studied. The thickness of the studied layers is from 10 to 100 μm, the frequency of exposure is 1000 Hz. It was found that the flexosignal takes maximum value in homeotropically oriented samples in the nematic phase. When approaching the N-I phase transition, the magnitude of the flex signal increases, which is associated with an increase in the deviation angle of the director of the LC. As the dipole moment grows, the quadrupole moment also increases. This is due to the tendency of LC molecules to form dipole pairs with antiparallel orientation of electric moments. The estimate of the flexural value U1ω
yielded (for example, for MBBA) with a planar orientation 3 times less than with a homeotropic one. The presence of the second harmonic U2ω
is a consequence of the orientational instability of surface polarization. The rapid growth of U2ω
is associated with an increase in the square of the director deviation angle

θ

¯

d

2

.
Optimization of energy supply schemes using GA
Authors: Bodrenkov E A , Korovkin N V 
Published: September 2020

Abstract
Presented a methodology for determining the optimal configuration of electric circuit by criterion of minimum active power losses in circuit using genetic algorithm. The advantage of the proposed approach is the reduction of number of operations required to calculate the parameters of the electric network mode and as a result increase the speed of search. The theoretical significance lies in the possibility of explicit determination of sensor elements when defining nodal loads by resistances. Practical significance lies in the possibility of applying the approach by electric grid organizations. The algorithm is tested on a model of an electric network with a voltage of 110 kV.
Photonic hook - a new type of self-bending structured light beams
Authors: Baranov P F , Zatonov I A , Bui D B 
Published: September 2020

Abstract
During the last 2 years, it was shown that an electromagnetic beam configuration can be bent after propagation through an asymmetrically shaped (Janus) dielectric particle, which adds a new degree of simplicity for generation of a curved light beam. This effect is termed “photonic hook” (PH) and differs from Airy-family beams. PH features the smallest curvature radius of electromagnetic waves ever reported which is about 2 times smaller than the wavelength of the electromagnetic wave. The nature of a photonic hook is a the dispersion of the phase velocity of the waves inside a trapezoid or composed particle, resulting in an interference afterwards.
Remote radiation monitoring device
Authors: Kulikova V A , Yakovlev V V , Tumanov A Yu , Tumanov V A , Kulinkovich A V 
Published: September 2020

Abstract
This article is devoted to the issue of the necessity of implementation of a remote radiation monitoring device. The main purpose of the article is to present a model of a remote monitoring device. During the research, the author considers the application areas of the device and presents technical requirements and design descriptions of the monitoring. Moreover, the researcher conducts the spectrometric equipment analysis of the device for accurate measurement of the level of radiation pollution. The device model proposed in the article is capable for secure monitoring for personnel and the public in the event of a radiation accident. The author states the importance of such monitoring device, which is primarily designed for automated radiation monitoring of environmental pollution during the operation of ships with nuclear power plants, ships of nuclear-technological services and ships transporting nuclear materials and radioactive substances.
Investigation of the capabilities of convolutional neural networks in object classification problems
Authors: Kozhevnikova T V , Kadura E V , Manzhula I S 
Published: September 2020

Abstract
This paper considers convolutional neural networks to solve the problem of improving the quality of images compressed by the JPEG algorithm. To analyze the qualitative characteristics of networks, the convolutional network L04 is implemented using the Caffe framework. By choosing the optimal optimization algorithm for training the network, its qualitative characteristics have been improved.
Chiral current reversal induced by a quadratic field in the three-leg magnetic lattice
Authors: Sun Tongyue , Zheng Yi , Yang Shi-Jie 
Published: September 2020

Abstract
We study the chiral current of non-interacting bosons in a three-leg lattice subjected to a uniform magnetic flux. The model is equivalent to a spin-1 bosonic lattice with three internal degrees of freedom or a one-dimensional lattice with a three-site synthetic dimension. By manipulating a bias field between the legs which acts as a quadratic Zeeman shift, we can effectively reverse the chiral current on the lattice. The current can also be reversed by increasing the magnetic flux or the inter-leg hopping coefficients, provided that the quadratic field is applied. Three types of current reversal, either related or unrelated to the Meissner-vortex phase transition, are revealed.
A novel system for the comprehensive collection of nonvolatile molecules from human exhaled breath
Authors: Chen Dapeng , Bryden Wayne A , McLoughlin Michael 
Published: September 2020

Abstract
Characterization of nonvolatile molecules in exhaled breath particles can be used for respiratory disease monitoring and diagnosis. Conventional methods for the collection of nonvolatile molecules in breath heavily rely on the physical properties of exhaled breath particles. Strategies taking advantage of their chemical properties have not yet been explored. In the present study, we developed a column system in which the surface chemistry between organic nonvolatile molecules and octadecyl carbon chain was exploited for the comprehensive collection of metabolites, lipids, and proteins. We demonstrated that the collection system had the capture efficiency of 99% and the capacity to capture representative nonvolatile molecules. The collection system was further evaluated using human subjects and proteins collected from human exhaled breath were characterized and identified using gel electrophoresis and bottom-up proteomics. The identified 303 proteins from mass spectrometry were further searched against reported bronchoalveolar lavage fluid proteomes and it was shown that 60 proteins have the tissue origin of lower respiratory airways. In summary, we demonstrate that our collection system can collect nonvolatile molecules from human exhaled breath in an efficient and comprehensive manner and has the potential to be used for the study of respiratory diseases.
Erosion and Sedimentation at Headwater Stream: A Case Study for Pergau Water Intake
Authors: Sulaiman Mohd Sofiyan , Mohd Amin Mohamad Faiz , Yusoff Abdul Hafidz , Samsudin Mohd Fikri , Shukor Aisah Md 
Published: September 2020

Abstract
Headwater stream can be defined as colluvial and fluvial system located at mountainous areas where stream order of less than four is recorded from the source to the outlet point of interest. This river system is crucial not only for impounding activities but high kinetic energy at highland areas able to entrain and transport large amount of sediment particles from upstream to the downstream river reach. Due to strategic location for water intake facilities, a study was carried out to determine the extent of erosion and sedimentation process at Pergau water intakes that conveyed water into Pergau Lake. Three specific aims were formulated: Soil loss determination at catchment scale, sediment load determination at reach scale and river bank stability and toe erosion near the intake facility. A desktop study using remote sensing and GIS tools was executed to determine the extent of soil loss at catchment scale. The sediment load and river bank stability were measured in the field using wading technique. It was concluded that all seven TNB water intake are having low soil loss rate (<10 ton/ha.year) should the current settings of forest land cover is maintained. The recorded sediment load (bed load) only occurred at Suda and Renyok 1 water intake with a rate of 0.0024 kg/s and 0.03 kg/s, respectively. High eroded material at toe was simulated at Renyok 1 and Suda Intake. The high sediment load at Renyok 1 is a manifest from unstable toe material near the water intake. Therefore, a close monitoring should be attained at the upstream from Renyok 1 intake to assess any land use change or disturbance activities.
Effect of Monsoonal Period toward Night-time Ground Level Ozone in East Coast Malaysia
Authors: Mohamad Nazir Amni Umirah , Awang Norrimi Rosaida , Ramli Nor Azam , Daliman Shaparas , Aziz Hasifah Abdul 
Published: September 2020

Abstract
This study aims to identify the effect of monsoonal period toward nighttime ground level ozone in East Coast Malaysia depending on different land use area which is industrial and urban areas. The concentration of O3, NO, NO2 temperature (T), relative humidity (RH) and wind speed (WS) were used and collected from Air Quality Division of the Department of Environment, Malaysia. The data proceeded in descriptive analysis and statistical analysis. Temperature, relative humidity and wind speed parameters (symbol of East Coast Monsoonal period), was compared with O3, NO and NO2 concentration with Pearson correlation analysis. During nighttime, O3 concentration continuously decreasing starting at 7 p.m. promotes by chemical removal and other removal processes. The highest nighttime O3 concentration was recorded 65 ppb (Kemaman) with the lower nighttime ozone achieved zero value. Meanwhile, nighttime O3 concentration in Kota Baharu (nighttime) was recorded lower with maximum (612 ppb) and mean (9.15±8.60 ppb) compared to Kemaman. The temperature and relative humidity correlation with O3 concentration in both locations shown different correlation as Kemaman - 0.149 and 0.212 while Kota Baharu exhibited 0.137 and -0.159. Meanwhile, wind speed has a positive correlation in both locations as Kemaman is 0.388 and Kota Baharu is 0.462 which indicates wind was a factor that induces ozone formation as ozone was transported to the monitoring area. Therefore, NO, NO2, T, RH and WS was not the only factor influences ozone depletion during nighttime as the correlation display was lower.
A GIS-Based Flood Vulnerability Assessment in Pasir Mas, Kelantan
Authors: Mohamd Hanan Nur Aniza , Abas Muhamad Azahar , Md Nor Amal Najihah , Mohd Amin Mohamad Faiz , Hassin Nor Hizami , Yusoff Abdul Hafidz , Awang Norrimi Rosaida , Mohamed Sulzakimin , Wee Seow Ta 
Published: September 2020

Abstract
The flood events are now intense because of localized physical and climatic factors, resulting in risks to the environment and the population. Besides, the difficult to identify the flood vulnerable area at Pasir Mas, Kelantan had become the main problem because lack of comprehensive information which as a medium to communicating the flood risk, new unplanned developments and insufficient drainage systems. Hence, the development of a vulnerability map for flood risk of flooding management still lacks, which made the situation more considerable. Vulnerability is the primary construct in flood risk management. Therefore, this study aims to identify the variables which contribute to the risk of flooding based on the characteristics of the area and develop a flood vulnerability map using Geographical Information Systems (GIS) and Remote Sensing. In this study, the land use data, amount average of rainfall data and digital elevation model (DEM) data were used to produce a vulnerable flood map for the study area. The hydrology and weight overlay (spatial analyst) techniques were used to determine the flood vulnerable area on physical and climatic factors that cause flooding in Pasir Mas and to develop the vulnerable flood map in Pasir Mas. The vulnerability area had been determined based on the scale 1 (no vulnerability), 2 (low vulnerability), 3 (reasonable vulnerability), 4 (moderate vulnerability) and 5 (high vulnerability). The findings show that the area located at the water bodies recorded the most highly vulnerable compared to another area because water bodies store the water. When surface water run-off from the surrounding area exceeds the level of water bodies, it increases the flow capacity of the water and causes the flood. From here, it makes the water bodies and area surrounded it more vulnerable. It is expected within this vulnerable flood map will able to assist the responsible parties to communicate and give an option to those affected people to ensure the effectiveness of the emergency response assistance and aid to victims for better preparedness capability.
Impact of land use changes on forest catchment area in Pergau Lake, Kelantan
Authors: Muhamad Nor Amal Najihah , Bahri Ayuni Samsul , Nor Shukor Md. , Yusoff Abdul Hafidz , Abas Muhamad Azahar , Jamil Rohazaini Muhammad , Aziz Hasifah Abdul , Nawawi Aisyah , Ibrahim Norfadhilah , Mohd Amin Mohamad Faiz 
Published: September 2020

Abstract
The Pergau lake basin is a man-made water catchment area comprise of 460 hectares due to the construction of hydroelectric dams in Pergau. It is located about 125 km southwest of Kota Bharu in the Jeli district in Kelantan and managed by Tenaga Nasional Berhad. The lake is rich in natural resources and the forest in the basin acts as a reservoir through water absorption and storage. Forests within the area catchments and basins can control soil erosion and erosion of river banks as well slope collapse is one of the sources of risk floods in terms of damage to property and infrastructure such as bridges and road. However, rapid population growth and urbanisation induced the pressure from human activities have been expanded into the forest catchment area. Therefore this study was conducted in the Pergau Lake (Dam) to safeguard their importance for socio-economic, well-being, ecotourism potential and sustaining its biodiversity. This study aims to predict the land use changes in the study area for 2035, parameterised with satellite images in 1988, 2003 and 2018 and the physical parameter such as slope, road, elevation, distance from built up area, green space edge and waterbody. The integrated approach of remote sensing, Geographical Information System (GIS) and Land Change Modeler-Markov Change Model were used to analyze the changes and their spatial pattern. The results showed that between 1994 and 2004, and between 2004 and 2014 the forest landscape in the Pergau Lake were decreased due to the development of the built-up area. Thus, the results will hopefully take into consideration for land use planning and forest protection for sustainable management planning of the forest catchment area. It is indicated that the spatial effect of green space is influenced by the historical spatial changes, implementation of the previous master planning efforts and uncontrolled land use expansion. This study is designed to provide the novel integrated approach for predicting landscape changes for the forest catchment area to provide the initial guideline for sustainable planning and management of forest catchment area.