bluuebunny/crossref_metadata_2025 huggingface dataset:
Geological Recognition and Expansion Potential Analysis of the New 172-52 Drilling Area
Authors: Zheng Jianghua , Qiao Shasha , Zhao Yue , Yi Jun , Wang Chao
Published: February 2021

Fine reservoir characterization is the basis of tapping the potential of high-yield exploration and evaluation wells. In this paper, the comprehensive prediction of New 172-52 reservoir in high-yield exploration and evaluation well area is carried out by using seismic data combined with drilling data, the sand body in the study area is re-depicted, and the geological understanding after drilling is integrated. It is concluded that the effective thickness of the well area on the east side of the fault in this area changes rapidly and gradually becomes thicker to the southeast, and the sand body is developed and has good connectivity, and there is potential for edge expansion above the oil-water interface. In the well area on the west side of the fault, according to the seismic reservoir attribute, the abandoned well after drilling is at the edge of the sand body, and the sand body extends to the northeast around the well point, and meets the fault block at the high part of the structure, which has the potential of expanding the edge. Through fine reservoir characterization, the boundary and scale of sand bodies are explored, and the productivity potential of high-yield exploration and evaluation wells is tapped.
Reservoir prediction and application of multi-attribute fusion
Authors: Wang Xingye
Published: February 2021

Under the existing well pattern density conditions, there are still uncertainties in the understanding of reservoir distribution in XX Oilfield. The main reasons are that the different sedimentary environments and complex and changeable sedimentary models lead to uncertainties in reservoir prediction under the guidance of sedimentary models; Second, the sedimentary mechanism of different types of sand bodies is different, and there are multiple solutions in cross-well prediction. Therefore, other means must be used for auxiliary analysis in reservoir prediction, so as to improve the accuracy of sand cross-well prediction. This paper focuses on the basic method of reservoir prediction based on seismic multi-attribute fusion, which can further improve the accuracy of cross-well prediction in the cross-well prediction of thick oil layers In addition, the sand body distribution characteristics corrected by multi-attribute fusion slice are applied to measure well selection and layer selection, and comprehensive analysis of remaining oil is carried out by integrating various disciplines, and relatively high-quality potential tapping horizons are determined, which further improves the coincidence rate of potential tapping by measures.
Study on the effect of fluid-structure coupling on the outlet Piping of reciprocating compressor
Authors: Yuan Wei , Wang Ying , Zhao Jie
Published: February 2021

The fluid-structure coupling has been one of the hot issues of academic research in recent years, the achievements in various fields of study also emerge in an endless stream, but on the current research status, The study of fluid structure interaction in the field of moving equipment, especially compressor, is not very common, With the development of industrial compressor, it is developing towards the direction of large scale and high parameter, Coupling analysis of fluid structure interaction can be used to evaluate the safety and stability of the system, and the evaluations are more close to the actual situation. Therefore, it has gradually been valued. Through the comparison and analysis of the vibration test system of the reciprocating compressor before and after the pipeline inflation, the vibration response caused by the coupling factor is obtained, for the correctness verification of the fluid-structure coupling simulation. the numerical model of the experimental system is established based on ANSYS, and the boundary conditions of the model are simulated by the experimental data, verified the feasibility of simulation program. the experimental and simulation results show that the fluid solid coupling characteristics are not obvious in the vicinity of the reciprocating compressor, and the effect is significant at the top of the buffer tank and the installation position of the orifice plate.
Analysis on the Effective Characteristic of Different Displacement Ways of Tertiary Oil Recovery in the Class II Reservoir of Sazhong Development Zone
Authors: Yu An
Published: February 2021

The first industrial tertiary oil recovery of the class II reservoir in the Sazhong Development Zone was the polymer flooding carried out in Block X at the end of 2002, and achieved noticeable effect. As the class II reservoir blocks were exploited one after another, by combining different geological structures and reservoir characteristics with distribution characteristics of remaining oil, the displacement modes successively went through polymer flooding, strong alkali ASP flooding, weak alkali ASP flooding, and salt-resistant polymer flooding, etc. Considering there are big differences in the geological structure, reservoir characteristics and layer combination of different class II reservoir blocks in the Sazhong Development Zone, and the development effects of different displacement modes are different as well; therefore, it is necessary to learn from the phased results achieved in typical blocks and leading pilot, on this basis, further conduct in-depth comparative study of the characteristics of effective rule and the changes of injection-production parameters of the class II reservoir blocks that have carried out tertiary oil recovery under different displacement modes, provide technical support and selection basis for betting modes up and down of the class II reservoir in the future, and it is of great practical significance to the realization of quality and efficiency improvement and sustainable development of the oilfield.
Problems and Research on Underground Charging Safety of Power Battery for Coal Mine Robot
Authors: Ma Long , Chen Qing
Published: February 2021

In order to further study the underground charging safety of power batteries for coal mine robots, this paper proposes to study the energy transfer mechanism of power batteries in confined space and the difference of energy distribution in flammable and explosive special gas environment. On the basis of theoretical research, the safety performance of the temporary flameproof chamber formed during the underground charging process of the robot is verified by constructing the detection experimental platform of the explosion-proof automatic charging device of the robot, so as to solve the problem of potential safety hazard assessment caused by exposed contacts or unreliable docking during the underground charging process of the coal mine robot, and provide theoretical and experimental basis for the underground charging safety.
Quantitative Evaluation Method and Application of Airflow Stability of Mine Ventilation System
Authors: Li Bingrui , Wang Wei , Li Peng , Chen Junkui , An Linghe
Published: February 2021

A quantitative analysis method is proposed for airflow stability evaluation of complex ventilation networks. The influences of resistance change on airflow and its variation laws are analyzed by mathematical statistics method based on the simulation of airflow state in ventilation network. It is proposed that the airflow change rate is used as the quantitative evaluation index of airflow stability, and the sensitivity branches and dominant branches of ventilation system are determined by the airflow change rate matrix. A set of airflow direction discriminants of complex network is derived based on the deep analysis of the correlation among resistance, airflow and airflow change rate of branches. The results show that the stability quantitative analysis results and airflow direction discrimination results of this method are consistent with the results of computer simulation of airflow state, and the airflow direction discriminants can be applied to any complex network.
Research on Resource Utilization of Municipal Solid Waste Landfill
Authors: Ma Jun , Gao Tao , Hu Lidan
Published: February 2021

Due to the advantages of simple landfill treatment process and low treatment cost, it is widely used at home and abroad. At present, many large cities are surrounded by landfills, which severely hinders urban development. This article starts from the existing problems of municipal waste landfills and discusses the realization of municipal waste landfill disposal and resource utilization.
The application of high-pressure rotary jet grouting curtain on the ocean engineering structure
Authors: Liu Wenbin
Published: February 2021

The high-pressure rotary jet grouting curtain is a common water-proof structure in civil engineering. This paper analysed the application of high-pressure rotary jet grouting curtain in ocean engineering based on construction of the western man-made island of the Shenzhen-Zhongshan Channel project, modelling the pile forming, shearing strength, and water proofing effect, and emphasizes the key points in the construction.
Characteristics and farmer’s response to climate variability to support sustainable agriculture: case study in Tasikmalaya, West Java
Authors: Estiningtyas W , Suciantini  , Dermoredjo S K
Published: February 2021

Rice farming is strongly influenced by climate conditions. The availability of water from rainfall is a major consideration for farmers when determining the start of planting, while the beginning rainfall will change due to extreme climate events. The impact of climate variability as floods, droughts and attacks from pests and diseases brings losses for farmers in their food farming. The purpose of this paper is to identify the characteristics and responses of farmers to climate variability for the sustainability of food farming. Farming system in Singaparna sub-district is mostly carried out by farmers who are over 60 years old with primary school education and land ownership < 0.5 ha. Climate variability has an impact in a shift in the beginning of the rainy and dry season. Climate variability has an impact in the form of a shift in the beginning of the rainy season and the beginning of the dry season. The area of land affected by seasonal shifts is a significant factor affecting production. Farmers’ characteristics and responses can be used as a basis for increasing the adaptive capacity of farmers to minimize risks to the impacts of variability and climate change.
Effect of various drying methods on the physical characteristics of arrowroot powder
Authors: Indrasari Y P , Karyadi J N W , Nugraheni N F , Tarwaca S N , Albyan R , Setiyadi I , Ayuni D
Published: February 2021

Arrowroot (Maranta arundinacea) is a large herb found in rainforest habitats. In Indonesia, Arrowroot (or known locally as Ubi garut) is usually processed into a powder ingredient for many foods such as puddings and cookies. One of the crucial processes in producing arrowroot powder is drying. In this study, the effect of various drying methods on the characteristics of arrowroot powder was evaluated. They were solar drying (SD), cabinet drying (CD), and pneumatic drying (PD). The pneumatic dryer used was self-made with a total dimension of 1600×500×2500 mm. It was made from stainless steel plate with 3 mm thickness and equipped with heater, blower, feeder, cyclone, and drying chamber (heater fins of 4,500 watts). The moisture content showed that the CD sample has the lowest moisture content than other methods. The PD has a great potential to be used to produce arrowroot powder while retaining its color and nutritive values.
Estimating of soil moisture using shetran model at Cisanggarung catchment area
Authors: Suroso  , Wahyuni R P , Ardiansyah
Published: February 2021

Soil moisture is one of the essential controls for the hydro-climatology processes. Soil moisture value can be used as an indicator of soil fertility so that it has a vital role in increasing agricultural and plantation production. Understanding the soil moisture variability on a spatial-temporal scale is very interesting in many practical applications such as drought prediction and agricultural modelling. The purpose of this study was to estimate the soil moisture value which distributed in space and time in the Cisanggarung River Basin with the spatial resolution of 500 m × 500 m and daily temporal resolution. The Shetran physical-based hydrological model was applied by utilizing hydro-climatological data derived from the remote sensing measurements from 2001 to 2017. The Shetran model input data consisted of the digital elevation model, land use land cover, TRMM rainfall data, evaporation data, and soil properties data. The results of this study indicate that Shetran hydrological model is reliable to estimate soil moisture in a watershed. This soil moisture values are then validated with the historical data of drought disaster.
Trend analysis of extreme precipitation indices in the southern part of Java
Authors: Abdila W P , Nugroho B D A
Published: February 2021

Global warming causes changing on climate system which driving extreme climate and metrological event. The occurrence of extreme event, such as extreme precipitation can lead to flooding and drought which can have an impact on agriculture production. To observe the extreme event, Expert Team for Climate Change Detection Indices (ETCCDI) developed 27 extreme indices which are 11 extreme precipitation indices and 16 extreme temperature indices. In this study, we analyze the trend of extreme precipitation indices to understand the changing of precipitation in Southern part of Java. Extreme precipitation indices were analyzed using Climpact2. Trend significance of extreme indices time series were calculated using non-parametric Mann-Kendall Test. Spatial distribution of the annual trend in each index illustrated using IDW interpolation. Most of significant trend in extreme precipitation indices occurred in North West station of study area. Negative significant trend only happened on consecutive wet days (CWD) index that means wet days was decrease. Positive significant trend happened in every index exclude consecutive dry days (CDD), Number of heavy precipitation days number of heavy precipitation days (R10mm), and PRCPTOT. Precipitation in study area occur with high intensity in short period.
Physical characteristic of instanised chocolate beverage powder produced with palm sugar and sucrose as sweeteners
Authors: Setiadi P A , Saputro A D , Nurkholisa Z , Hardiyanto Y F , Bintoro N , Karyadi J N W
Published: February 2021

Cold cocoa beverage is one of the derivative products of cacao. It has sweet taste and refreshing sensation which is popular in tropical countries. Sweetener is added mainly to reduce the bitterness of the cocoa powder. Normally, before adding ice cube, hot water is used to dissolve cocoa drink powder. Nevertheless, this method is not efficient. Therefore, a method that can produce cocoa drink powder which can be easily dissolved is required. This study aimed to investigate the impact of palm sugar: sucrose (P:S) proportion and drying duration on the characteristics of cocoa drink powder made using continuous-type steam jet agglomerator. The result showed that the solubility, bulk and tapped density increased as the proportion of palm sugar and drying duration increased. However, the lightness tended to be comparable and moisture content after drying process decreased as the proportion of palm sugar increased.
The hardness analysis of noodles made from modified cassava flour, spirulina (Spirulina platensis) and basil leaves extract (Ocimum sanctum L.)
Authors: Al-Baarri A N , Widayat  , Aulia R , Prahasiwi E K , Mawarid A A , Pangestika W , Lestari F P
Published: February 2021

The alternative solution for high import costs of wheat flour is by substituting wheat flour with mocaf (modified cassava flour). Mocaf is a modification of cassava flour made by fermentation treatment using lactic acid bacteria, acetic acid or enzymes. However, mocaf has a low gluten and protein content so it might produce noodle products with a poor texture. Therefore, it is necessary to add other ingredients in order to increase protein content and change the appearance, one of which is fortification with spirulina. Spirulina has a natural aroma like the smell of fresh seaweed with a slightly fishy aroma that comes from the high protein content. Hence, it is necessary to add basil leaf extract which can give a distinctive smell of basil to overcome the fishy aroma of the noodles. This research was conducted to determine the texture of modified noodles from mocaf with the addition of spirulina and basil leaf extract using a texture analyzer. Based on the research conducted, it was found that the addition of basil and spirulina leaf extracts could affect the texture of mocaf noodles to become more chewy, dense and not easily broken.
Optimization of simple sugar extraction of nagara bean (Vigna unguiculata ssp. Cylindrica) on concentration and proportion of ethanol
Authors: Susi S , Udiantoro  , Gendrosari S
Published: February 2021

Nagara bean, the native bean of South Kalimantan, is not only contains carbohydrates and protein, but also contains oligosaccharide fractions such as raffinose and stachiose that can cause flatulence. Raffinosa Family Oligosacharide (RFO) is an undigested carbohydrate that is naturally found in beans. The presence of the oligosaccharide fraction can be identified through reducing sugar and total sugar content in nagara bean. The yield of this fraction depends on the type of material and extraction method, such as the type of solvent, solvent concentration, contact time and extraction temperature. This study was aimed to optimize the extraction of simple sugar fractions on nagara bean at several concentrations of ethanol with various ratio of nagara bean flour to ethanol using the Response Surface Methods (RSM). Optimization was carried out at the center point ethanol concentration of 50% and the ratio of nagara bean flour and ethanol of 1: 10. The optimization results of the simple sugar fraction extraction process in nagara bean flour were obtained at a concentration of 30% ethanol and a ratio of ethanol to nagara bean flour of 10: 1 at extraction conditions at 50° C and extraction time of 30 minutes.
Endophytic bacteria: an emerging tool for biological control bacterial leaf blight of paddy
Authors: Prihatiningsih N , Djatmiko H A , Lestari P
Published: February 2021

Endophytic bacteria were isolated from the root of paddy, not negative influence even could serve as plant growth promoter and pathogen biocontrol likely Xanthomonas oryzae pv. oryzae caused of bacterial leaf blight. The research was aimed to know the effectivity of controlling the endophytic bacteria against bacterial leaf blight of paddy. Methods of this research were suppressing effect to control bacterial leaf blight with seed dipping and soaking the endophytic bacterial suspension on surrounding plant in the polybag. Nine bacterial and one control were treatment in this assay and three replicates, arranged with randomize completely block design. Endophytic bacteria isolated from roots of paddy were evaluated for their capacity to suppress bacterial leaf blight intensity, infection rate and the effectivity control. The result showed that the endophytic bacteria could suppress the disease, and the isolate of SB1 (from Sumbang 1) is the best for antagonistic effect by 64.16% and 49.14% effectivity at screen house and paddy fields respectively. Infection rate of this disease was slow by 0.024 unit.day−1 and different with the control was 0.088 unit.day−1.
Seed treatment to improve seedling establishment in the anaerobic conditions
Authors: Wahyuni S , Agustiani N , Salma S , Widiastuti M L
Published: February 2021

Limited farm labor in swampy area encourage farmers to apply direct seeding method, however land conditions with excess water caused un-germinated seeds. The purpose of this research was to obtain seed treatments to increase seedling establishment in anaerobic germination conditions. The first experiment was laboratory trial arranged in a factorial design with two factors namely seed treatments and rice varieties. A total of 32 treatments along with control were tested on three rice varieties: Inpara 9 (swampy variety), IR 42 (AG-susceptible), and KHO (Anaerobic Germination/AG tolerant). The results showed that treated seeds show faster germination and has higher germination index. The second experiment was greenhouse trial to confirm the effectiveness of 12 best seed treatments from the first experiment. Water managements were conducted in anaerobic and aerobic conditions. Seeds on anaerobic conditions decreased seedling establishment, shoot length, root length, shoot dry weight, and root dry weight for 44.6, 28.1, 34.4, 80.7, and 74.2%, respectively. KHO showed better performance in anaerobic conditions. Treated seeds had better seedling establishment and seed growth in anaerobic conditions, except for hardening Trichoderma treatment. The best three seed treatments in anaerobic conditions were hardening H2O, thermo treatment 80°C+NaOCl, and hardening ascorbic acid.
Prediction of surface runoff and erosion rate using SWAT (soil water assesment tool) model in Selopamioro catchment as directions of soil and water conservation
Authors: Habib H , Ngadisih  , Tirtalistyani R , Susanto S , Nurudin M
Published: February 2021

Selopamioro catchment part of Oyo Watershed, is located in downstream area of Selopamioro village which consist of steep slope gradient, and has been constantly exposed to intensive farming activities. Thus, this watershed is susceptible to erosion. One of models to predict the impact of land use on hydrological and sedimentary conditions is SWAT (Soil Water Assessment Tool). Therefore, the purpose of this research was to apply the SWAT model in predicting surface runoff and erosion. The result of this study will be used as initial analysis to support the direction of soil and water conservation. Topography, land use, and climate data were collected to simulate erosion and surface runoff. Two adjacent sub-catchments namely DTA 1 and DTA 2 were analyzed. Surface runoff in DTA 1 is 333,660,000 liters/year and in DTA 2 is 316,920,000 liter/year. The erosion rate in DTA 1 is 24.6 mm/year and in DTA 2 is 21 mm/year. The result of SWAT model tends to be overestimate. This shows that SWAT model might not suitable to be used for erosion prediction in tropical agriculture country, such as Indonesia. Updates of SWAT data for physical characteristic in tropical country might need to be carried out for reliable result.
The role of pre-treatment in enhancing yield and antioxidant activity of lemongrass (Cymbopogun citratus) essential oil
Authors: Erminawati  , Naufalin R , Sidik W , Rahman F A
Published: February 2021

Sample preparation before distillation is an important step in producing high yield and good quality of lemongrass (Cymbopogun sitratus) essential oil. In order to improve the production process and to provide information as reference for further practical applications, the effects of sample pre-treatment (with and without microwave heating) and distillation time (3, 4, and 5 h) were studied. In addition, the samples types (dried stem and dried leaf) were compared. Results of the study suggested that the highest antioxidant activity of lemongrass essential oil (86.33%) was obtained from lemongrass dried stem that were heated in microwave and distilled for 4 h with yield of 2.307%. While the highest yield of lemongrass essential oil produced (2.63%) was obtained from lemongrass dried stem that were heated in microwave and distilled for 5 h with antioxidant activity of 69.67%. Based on the results, it can be concluded that lemongrass stem contains higher essential oil compare to that of the leaf and microwave heating before distillation gave higher yield and better quality of the product.
The “PATBO SUPER” technology innovation to increase rice production in rainfed rice fields
Authors: Sari R , Sutrisna N , Surdianto Y , Liferdi
Published: February 2021

SUPER PATBO technology is adoption from IPAT-BO technology with some enhancements to make it suitable for rainfed areas. It has been adapted in several locations. There are five main components of PATBO SUPER technology, namely: (1) New Superior Varieties of the amphibian group; (2) Water management at the macro and micro levels; (3) The use of in situ organic matter and biological fertilizers; (4) An effective and efficient weed control; and (5) Agricultural machinery application. The results of the several studies show that the PATBO SUPER technology has a good performance in several locations, namely in Ujungjaya District, Sumedang District and Palasah District, Majalengka Regency. Rice productivity in Ujungjaya Subdistrict increased by 33.51%, from 5.64 t/ha with the technology commonly applied by farmers to 7.53 t/ha with SUPER PATBO technology. In Palasah District, Majalengka Regency, it can increase rice productivity by 20%, from 5.70 t/ha to 6.84 t/ha. The application of PATBO SUPER technology is also financially profitable as indicated by a BC Ratio of 1.49 and an MBCR of 14.18. The dissemination of PATBO SUPER technology can be accelerated by establishing a field laboratory in each development target area.
The nutritional value of agricultural waste forages fed to ruminants from agroecosystem in Grobogan Regency
Authors: Prasetyo A , Suhendrata T
Published: February 2021

This study examines the nutritional composition of tropical agricultural waste forage fed to cattle, sheep, and goats (ruminants). The explanation for the variation in nutrients between forages depends on soil fertility and water adequacy in upland agroecosystems. Agricultural waste ingredients for ruminant livestock feed come from rice straw, corn, soybeans, and the carrying capacity of these feeds. Agricultural waste feed ingredients are arranged in a complete feed formula. The nutritive value of complete feed includes crude protein, crude fiber, crude fat, energy, and ash. The aim of this study is to make complete feed of ruminants as animal feed for cost efficiency and feed stock in the dry season.
Climate stresses and its impact towards food sufficiency: a case in Bantul regency Yogyakarta-Indonesia
Authors: Fitriana L , Susanto S , Ngadisih  , Setyawan C , Tirtalistyani R
Published: February 2021

Biomass production is influenced by climate, soil, and water. The most uncontrolled factor is climate. Climate change increases the hazard of hydrometeorological disasters such as floods and drought which influences harvest area an agricultural commodity. This study was purposed to identify and analyze the impact of climate stress on food sufficiency in Bantul Regency, at Special Region of Yogyakarta. Later, it was applied to recommend a strategy in achieving food sufficiency in Bantul. Here, dynamic modeling was applied to simulate the supply and demand for food. Rice is staple food in Indonesia, so it was selected in the simulation of food sufficiency in this study. The modeling used rice production, population, urbanization, and rice field area data released by the Statistic Agency of Bantul. The range of data was 10 (ten) years i.e 2010 to 2019. MAPE (Mean Absolute Percentage Error) was used to validate the model. The MAPE of rice production was 8.36%, so the modelling of climate stresses and its impact towards food sufficiency was accepted. This study identified that food sufficiency in Bantul would finish in 2026. The increasing crop index from 2.34 to 3.00 could extend the period of food sufficiency up to 10 years.
Assessing the emerging agribusiness entrepreneurs by using brainwave technology
Authors: Dharmawan B , Rosyad A , Mandamdari A N , Zulkifli L , Sunendar  , Silitonga L M
Published: February 2021

Individual attributes positively influence the success of entrepreneurs, so that it is important to be learnt by potential youths’ entrepreneurs by providing mentor from relevant business. To address this, we introduce Electroencephalography (EEG) or brainwave to investigate the attention and meditation level of students in entrepreneur skill and to develop an original approach to entrepreneurship learning about innovation. We constructed an integrated system of EEG brainwave in which each participant could be engaged in a virtual product design activity. The participant’s creative behavior, brainwave state, and the level of creativity of their virtual product observed and recorded simultaneously to understand the creative process and their creative product were evaluated afterwards. The experiment involved 20 students of agribusiness study program from different semesters. The result of the students’ exam was compared to their level of attention and meditation, then analyzed. The experiment showed that “attention” was more dominated to keep the brainwave technology work rather than to explore many entrepreneur paths explained by the teacher. Further investigation showed the difference of entrepreneur thinking’s priority before and after experiment, i.e. creativity-risk taking-decision making into risk taking-creativity-decision because students had different perceptions on how to become the successful agribusiness entrepreneurs after the experiment.
Research of recognition accuracy of dangerous and safe x-ray baggage images using neural network transfer learning
Authors: Andriyanov N A , Volkov Al K , Volkov An K , Gladkikh A A
Published: February 2021

The article considers the use of neural networks to solve the problem of recognizing dangerous and safe objects carried in the luggage of airport passengers. A comparative analysis is performed to define the accuracy achieved on the test sample for different convolutional neural networks. It also explores the influence of various regularizations on the accuracy of a two-class classification. The increased probability of correct recognition is achieved due to augmentation, reset weights and saturation of the network. The method of transfer training is used to increase the efficiency of the recognizer. In this case, a study was carried out for the transfer of various neural networks.
Identification of factors affecting accidents on the intercity road network
Authors: Baklanova K V , Voevodin E S , Fomin E V , Kashura A S , Cheban E P
Published: February 2021

This article examines the influence of various factors that affect the accident rate on the intercity road network. Ten road sections that differ in the level of accidents, traffic characteristics and geometric parameters were selected for the research. The experiment conducted with the help of specialized equipment showed that these road sections with similar parameters of the roadbed being in compliance with all standards have a strikingly different accident rate. The lack of correlation between the measured standardized indicators of road sections and the accident rate on them indicates the influence of unaccounted factors on the latter indicator, which are not considered by approved methods.
Determination of geometric characteristics of friction areas in contact of the chassis wheel with a solid support
Authors: Balakina E V , Sarbaev D S , Sergienko I V
Published: February 2021

Elastic wheels contain the chassis of airplanes, automobiles and other vehicles. Their tires interact with a solid supporting surface – roads and airfields. As a result of this interaction, only static friction, only sliding friction or a combination of them, depending on the mode of the wheel movement, can be present in the contact patch. The geometric dimensions and relative position of the different friction areas determine the stable, unstable or boundary movement of the elastic wheel. Purpose of work: calculation and measurement of geometric characteristics of static and sliding friction areas in the wheel-to-road contact. Determined that: the slip area appears on the longitudinal axis of the contact patch, at a distance from the center of the contact patch equal to 1/4 of the length of the contact patch, then it increases due to a decrease in the static friction area; the center of the static friction area in the contact patch moves toward the current moment by an amount proportional to the moment; the maximum displacement of the center of the static friction area corresponds to the moment maximum in terms of adhesion, and is 1/3 of the length of the contact patch.
Development of optimal modelling of thin-walled elements in the form of a shell made of composite materials
Authors: Bokhoeva L A , Baldanov A B , Chermoshentseva A S
Published: February 2021

The paper presents the research of the stress-strain state of a multilayer composite shell. The optimal construction of a multilayer shell made of composite materials (CM) in the ANSYS system is determined. The optimal construction of a multilayer composite shell provides maximum strength and rigidity at specified loads. An automated procedure developed for choose the angle of fiber laying in the layer. According to the calculations and constructed models, an experimental model of a multilayer shell made of laminated fiberglass manufactured. For the experimental manufacture of a multilayer shell by cold forming, the working drawings of the press-form made. We manually put the layers of shell made of fiberglass T-25 (BM) TU 6-11-380-76. We made layer-by-layer laying of layers in strict accordance with the calculation model, while observing the sizes of elements and reinforcement angles along the base in each layer. The surface of each layer is an ED-20 epoxy resin with a hardener. This approach can be widely used in the engineering and manufacture of structural elements and products from composite materials.
Influence of inertial links on the distribution of vibration amplitudes of points of the working body of a technological vibrating
Authors: Eliseev A V , Kuznetsov N K , Eliseev S V , Vuong Q T
Published: February 2021

Features of problems of dynamics and formation of dynamic states of working bodies of vibrating technological machines are considered. The purpose of the work is to develop a method for constructing mathematical models of vibration machines that provide the ability to evaluate, control and adjust the forms of movement of working bodies by introducing additional links into the structure of the system, forming a closed internal contour. Methods of structural mathematical modeling are used in the construction of original structural formations of their typical elements. The direction of constructive and technical solutions in the implementation of approaches to configure and adjust the structure of the vibration field of the working body is proposed. The method is implemented using the analytical apparatus of the automatic control theory. The features of dynamic states formation based on the application of transfer functions of structural mathematical models of mechanical oscillatory systems are studied. The use of transfer functions of interpartial connections for the formation of vibration fields of working bodies is proposed. Analytical relations are obtained that determine the possibility of implementing specific dynamic modes, including the decoupling of movements by individual coordinates, taking into account the features of the connectivity of movements by characteristic points of the working body, the manifestation of oscillation nodes or modes of dynamic damping. Features of using structural mathematical modeling methods in problems of dynamics of mechanical oscillatory systems with additional connections are discussed. The work is aimed at specialists in the field of theoretical and applied mechanics, machine science and mechanical engineering.
Mathematical model for studying the braking distance of a car equipped with ABS in winter conditions
Authors: Fedotov A I , Gromalova V O
Published: February 2021

The article aims to develop a mathematical model for analytical studies of the braking process of a car equipped with an anti-lock braking system in order to identify the relationship between the stopping and braking distances of a car and pedestrian visibility in dark winter conditions, when headlights are contaminated with anti-icing materials. The mathematical model of the braking process of a car equipped with ABS was analyzed. Experimental studies of the braking process of a car with running and disabled ABSs were carried out on winter roads. The experimental studies of headlight contamination with chemical anti-icing materials (CAIM) and changes in luminous intensity were carried out in real road conditions in winter. The results are presented in the article. The results of the experimental studies of pedestrian visibility in dark conditions with contaminated headlights are presented. The adequacy of the mathematical model of the braking distance of a car with running and disabled ABSs in winter conditions was assessed. The trends characterizing the effect of headlight contamination on the pedestrian visibility in dark winter conditions are described. The results of the study are presented in tables, diagrams and equations. The values of the stopping distance were determined at different initial braking speed rates. The visibility distance for a car with contaminated headlights was determined in dark winter conditions.
The influence of flank lands of end mills on machined surface in milling in the context of chatter
Authors: Dyadya S I , Kozlova Ye B , Tretiak V I , Kondratyuk E V
Published: February 2021

Reliability and cost-effectiveness are the main requirements for aircraft materials and structure components used in manufacturing of aviation engines. This defines the requirements for them. The majority of components are thin-walled and made of hard-to-machine materials: nickel and titanium alloys, heat-resistant steels. The use of such materials places restrictions on the use of certain cutting modes. During rough milling and semi-finish milling with end-mill cutters chatter occur. The vibrations deteriorate the machined surface of engine parts, tool life decreases and machine units are worn out. Different process technologies and constructive features of tools are used to decrease the intensity of chatter. The use of end mills having lands has yielded mixed results. The influence of land usage on surface condition and decrease of chatter in up-milling and down milling has been studied. The mechanism of influence on machined surface and chatter in up-milling and down milling has been determined. At the experimental stand studies were carried out on its effect on changes in the laws of motion of detail during the cutting process. It has been shown that in up-milling and down milling, a land fl
= 0.05 mm wide on the rear surface along the cutting tooth reduces the intensity of chatter has been shown. The results can be used to select the feed direction to reduce the intensity of chatter when milling thin-walled parts with end mills with a land on the rear surface along the cutting edges.
Formation of spatial responses of the optical field in the region of location of the optical antenna array
Authors: Pasternak Yu G , Safonov K S , Safonov F S , Fedorov S M , Volodko A V , Ischenko E A
Published: February 2021

This article describes a model of an optical antenna array operating in the mode of receiving electromagnetic waves in the frequency range 30-300 THz (in this case, the wavelength varies from 10 ☐ m to 1 ☐m). In the course of numerical experiments (to solve the system of Maxwell equations in the integral formulation, the Weiland method [31] was used) the accuracy of approximation of the spatial structure of the optical field at the points of the “virtual” antenna array elements using the auxiliary field sources method was studied. A study was also carried out on the possibility of using a virtual antenna array formed on the plane of arrangement of elements of a real array to increase the resolution of a multichannel optical system. At the upper frequency of the analyzed range of 300 THz, the wavelength is 1 ☐m. The lattice period was chosen equal to half the minimum wavelength of d=0.5 ☐m, so that it was possible to approximate the spatial distribution of the field in the space between the elements of the antenna array, in accordance with the requirement of the Kotelnikov-Shannon theorem.
Use of “virtual” antenna array methods for reduction of DO A estimation systematic error caused by the scattering of waves on mobile carrier body
Authors: Pasternak Yu G , Ashikhmin A V , Rembovsky Yu A , Fedorov S M , Razinkin K A , Antipov S A
Published: February 2021

Article shows that “virtual” antenna arrays can be used to effectively improve the DOA estimation accuracy of mobile direction finders. “Virtual” antenna arrays are the samples of the spatial field distribution calculated by approximation of the field near a three-dimensional scattering body that supports physical (“real”) antenna system. Signals from the outputs of the “real” array are used as input data for the approximation process. Information on the geometry and material properties of the medium is not required. This procedure can be based on the main provisions of electrodynamics (Kirchhoff-Huygens principle, the Lorenz lemma, method of equivalent currents and fields) or on the use of quasi-static approximation of the field based on the apparatus of the theory of analytic functions of a complex variable (the Cauchy integral and Laurent series). “Virtual” arrays can reduce the error caused by the carrier body without costly and labour-intensive calibration procedures.
Guidance dynamics of the optical load of a multielement manipulator
Authors: Tochilkin N E , Kimyaev A I , Sheval V V
Published: February 2021

The dynamic equations of a flat motion of the angular-type multielement manipulator are considered; the manipulator has the payload as an image formation device of a mobile observed object. Dynamics constraints of a manipulator-driven load via stepper motors are investigated. Nonlinear control algorithms are suggested for the tracking of an observed object via feedback actuators associations operating as one multicoupling control feedback actuator.
Using refrigeration machines and heat pumps in the cycle of oil preheating using electricity
Authors: Osintsev K V , Shishkov A N
Published: February 2021

Tank electric heating systems are designed to compensate for heat losses to the environment. The main way of heating technological machines in the negative ambient temperatures is electric heating. Also, electric heating serves to prevent phase changes in the energy carrier. Furthermore, it is needed to control the required viscosity and maintain the set temperatures. The problem of limited resources has always faced humanity. In the field of energy this problem is now more urgent than ever before, because every year, the planet’s hydrocarbon reserves are becoming less and less. Hydrocarbon cost is increasing, which leads to an increase in the cost of the final product. Therefore, it is necessary to use resources more efficiently, increase the efficiency of equipment, and introduce new technologies. In addition to limited resources, the problem of environmental pollution is no less acute.
Calculation of sealing pressures of shut-off valves
Authors: Pogodin V K , Belogolov Yu I , Gozbenko V E , Kargapoltsev S K , Olentsevich V A , Gladkih A M
Published: February 2021

The proposed algorithm for calculating the sealing pressures of the shut-off valve allows one to take into account the structural features of its components and their elements that affect the amount of sealing pressures. These parts are divided into the mounting system and sealing system. Analytical dependencies for determining the forces acting in these systems allow us to determine the force values when tightening fasteners, during pressure buildup and release, and also when exposed to temperatures. When calculating the specific structure of the shut-off valve, it is shown that the forces in its sealing system and mounting system exceed the values determined by known methods of calculation, respectively, 1.4 and 1.2 times. The magnitude of these discrepancies for different structures of shut-off valves may differ from those indicated and depends on the number of components included in the stop valve station. In this regard, the proposed calculation method allows determining not only the forces in the shut-off valve, but also the optimal number of components and connections that will ensure safe operating conditions. It is shown that the method of calculating forces in the stop valve station used in practice is a special case in which the stiffness coefficient of the stop valve station α = 1. The proposed calculation method makes it possible to more accurately determine the forces acting in the shut-off valve, the sealing conditions and the stress-strain state of the components. The introduction of the developed calculation method is connected with the development of a regulatory document on its basis to replace the existing methods of calculating the stop valve station in shut-off valves.
Method for determining the sealing forces in a shut-off valve
Authors: Belogolov Yu I , Pogodin V K , Gozbenko V E , Kargapoltsev S K , Olentsevich V A , Gladkih A M
Published: February 2021

The developed method for determining the sealing forces in a shut-off valve takes into account the design features of its components and their elements, which affect the amount of sealing pressure. The components and assemblies of the shut-off valve that provide the creation of sealing pressure are referred to the fastening system or the sealing system. Dependences for determining the forces acting in these systems are analytically revealed. The values of forces are determined when tightening fasteners, when increasing and releasing pressure, as well as when they are exposed to temperatures. The calculation of the specific structure of the shut-off valve shutdown showed that the forces in the sealing system of the check valve prototype are 1.4 times higher than the values obtained using known calculation methods, and the forces in the mounting system of this check valve are 1.2 times higher than the calculated values. The magnitude of the discrepancy between the calculated and actual values of the forces for different designs of shut-off valves may differ and depends on the number of components included in the station shut-off valve. The proposed method for determining the sealing forces in the shut-off valve makes it possible to determine not only the forces in the shut-off valve, but also the optimal number of components and connections that will ensure safe operating conditions. It is shown that the method of calculating the forces in the station shut-off valve, used in practice, is a special case in which the stiffness coefficient of the station shut-off valve is equal to unity. The proposed method for determining the sealing forces in the shut-off valve makes it possible to more accurately determine the forces acting on the shut-off valve, the sealing conditions and the stress-strain state of the components. To implement the developed methodology for determining the sealing forces in the shut-off valve of the stop station in the shut-off valves, it is necessary to develop regulatory documents formalizing the application of this method.
Analytical studies of bottom hole assembly dynamics in directional well while drilling with coiled-tubing system
Authors: Zainagalina L Z , Zinatullina E Ya , Safiullina A R
Published: February 2021

The article is devoted to the relevant topic of more accurate selection of the design of the bottom-hole assembly (BHA) with a hydraulic test stand to create the necessary axial stress on the bit during drilling with coiled tubing rigs. A mathematical model of the BHA as a dynamic system with linear coefficients during longitudinal vibrations while drilling wells with a coiled-tubing system has been developed and analytically investigated. Analytical dependencies for determining the dynamic parameters of coiled-tubing BHA by a hydraulic test stand have been refined when operating in a directional well.