bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitivity analysis of factors affecting for the engraving of rifle projectile
Authors: Li J M , Yan W M , Lu D B , Wang Sh , Qu Y J 
Published: January 2021

Abstract
In order to study the primary and secondary relationship between the factors affecting the engraving resistance of one small-caliber rifle projectile, quasi-static push tests were carried out for jacket material by H90 copper and copper clad steel projectile in three kinds of gun barrels with different structures and the corresponding changes of the engraving resistance were obtained and analyzed. At the same time, numerical simulations were carried out for constant high-speed extrusion. Quasi-static test and dynamic simulation results were analyzed, the order of the factors affecting the peak of engraving resistance under quasi-static is the yield strength of jacket>free stroke> engraving length>rifle number> lead, and the factors affecting the peak of extrusion force under high-speed is engraving velocity>yield strength of jacket>free stroke> engraving length >rifle number>lead. It is also found that the relative steady engraving resistance value is close 60% of its peak value under quasi-static, while the same value under high-speed is between 1/8 and 1/6 of the peak value, the results of force peak are basically quite.
Application and verification of Sarrau formula in order to calculate pressure acting on the projectile’s base in the 120 mm Leopard 2 A5 tank’s barrel with piezoelectric pressure sensors and Doppler radar usage
Authors: Wasilewski Aleksander , Weiss Janusz , Kowalik Grzegorz 
Published: January 2021

Abstract
Semi-empiric Sarrau formula relates to a pressure acting on a breech with a pressure acting on the base of a projectile during a shot. Pressure acting on a breech is relatively easy to measure in comparison with pressure acting on projectile’s base. Exact value of projectile’s base pressure can be used in mechanical calculations for projectile, such as strength of a projectile’s body and its acceleration which is essential for example in designing of fuzes. In the paper authors make an attempt for definition coefficient of Sarrau formula to calculate a force acting on projectile’s base. In the paper results of 120 mm Leopard 2 A5 barrel’s shooting tests were used. The results contain pressure in the chamber during a shot measured with a piezoelectric pressure sensor and muzzle velocity measured with a Doppler radar. Piezoelectric sensor registered pressure waveforms. On that basis force acting on the breech was calculated, subsequently force acting on the projectile’s base was calculated with Sarrau formula, kinetic energy and work of the projectile in the barrel. Combining those, muzzle velocity was calculated and compared with muzzle velocity measured with Doppler radar. On that basis the coefficient was determined. The coefficient was later verified with the following shooting tests on 120 mm barrel. Conclusions describe issues during gathering data and results of Sarrau formula verification.
Different aspects connected with the lubricants and harmful exhaust gases
Authors: Esbulatova A , Voinov K , Nasr T , Ghellab Y , Belili O 
Published: January 2021

Abstract
In this paper many important aspects connected with the lubricants are described, namely: the first, the cheapest organic lubricant in the world which effectively saves lubricant between pairs of friction in any operation. The second position is connected with the rational shapes for the lubricants which have to work decreasing wear and tear using the new organic lubricant; moreover, this lubricant is the cheapest in the world. Made experiments confirm this effect in full; some curves are shown in computer program MathCad with calculations. The third part in this article is linked with the plastic lubricant and with the attempt to save it into the tight zone of the contact in pairs of friction. The fourth aspect: there is one physical model which helps to catch car exhausted gases. It’s very important to protect our environment against both the harmful gases and from the overheating for the air in atmosphere. In conclusion, some recommendations are given to realize them into the practice during the operation for the different mechanisms including ecology process.
Study on the information chain of sudden pollution accident
Authors: Liu Y , Zhao W J , Luo Y L , Du Q Y 
Published: January 2021

Abstract
The sudden pollution accident in a river basin is combined with accident cause, cause factor (pollutants) and the receptive environment all together, this study brings up the method to establish the information chain of sudden pollution accidents in a river basin which can describe the causality of all information. Take the sudden oil pollution accident in a river basin as an example, the information system of sudden pollution accidents in a river basin is established from five aspects: pollution source characteristics, pollution characteristics, regional environment characteristics, lash-up treatment technology status and pollution impact characteristics. Through index abstraction and structure representation for the above information, and connect the interactive relationship of the node variables with directed edge line segments, based on which the expert knowledge analysis synthesis method is applied to achieve the optimal causal direction relationship, and the information chain of sudden oil pollution accident in the river basin is ultimately established. This information chain can sufficiently show the causal relationship of each information elements in the sudden pollution accident and can supply decision making basis for examining and distinguishing the status of a sudden water pollution accident in a river basin and determining the precise lash-up treatment technology.
Retrospective analysis of phytoplankton community structure in water bodies of South Ural (Russia)
Authors: Kostryukova A , Mashkova I , Shchelkanova E , Trofimenko V 
Published: January 2021

Abstract
The current paper considers changes of phytoplankton community structure in three South Ural (Russia) water bodies different in trophicity: Lake Uvildy, Lake Ilmenskoe, and Shershnevskoe Reservoir. There is no clear relation between the changes of species structure of phytoplankton communities and water-bodies trophicity. The least significant changes in the phytoplankton community structure are registered for the mesoeutrophic Lake Ilmenskoe, which is located on the territory of the State Reserve. Diatomic, green and blue-green algae groups are the most diverse in composition in the studied periods of 1936-1937, 1964-1984 and 1998-2016. But for the last 20 years, Cyanophyta has increased its contribution into the phytoplankton number and biomass of Lake Ilmenskoe. The representatives of the Bacillariophyta group dominate in oligotrophic Lake Uvildy. In 1965-1985, the Chlorophyta group was the most abundant in Shershnevskoe reservoir (34 % of the total number of species), Bacillariophyta -32 % and Cyanophyta – 18 %. In 2003-2005 and 2017 the number of green algae increased (Chlorophyta – 40 %) and that of diatoms decreased (Bacillariophyta -21%) with the number of blue-green algae being unchanged (Cyanophyta -19 %). The ecological status of the Shershenevskoe Reservoir has transformed from a long-term sustainable mesotrophic to eutrophic. So, for oligotrophic lake Uvildy and mesoeutrophic lake Ilmenskoe, Bacillariophyta group is characterized by the greatest taxonomic diversity. While for eutrophic Shershnevskoe Reservoir the absolute abundance of Chlorophyta algae group is marked, which is growing in time. The growing importance of blue-green algae is one more feature of the change of a trophic status.
Effects of ecological water diversion in coastal plain river network considering different control plans
Authors: Wang J M , Wu J F , Fu L , You A J 
Published: January 2021

Abstract
The water environment in coastal plain river network becomes serious due to its dense population and low flow rate, the ecological water diversion is widely accepted as an effective method to improve the water quality in coastal areas. As a typical coastal city in China, Pinghu city has suffered from the serious water quality problem for years especially in the downtown area. Therefore, the local water diversion project has been constructed since 2010 for the purpose of providing an efficient way to improve the river network water quality. However, a systematic research of the control plan of water diversion is still necessary. In this study, a numerical model is introduced to predict the improvement of river network water quality considering different control plans. The simulation results comparison among different water diversion control plans show than the pre-drainage plan obtains the best water quality in this coastal plain river network, and it becomes a good choice for the local government to further improve the regional water environment.
Study on modulation technology of highway regional wind field
Authors: Li Y Y , He Y K , Hao S F , Jia Y 
Published: January 2021

Abstract
In this paper, through numerical simulation, the modulation effect of trees on the wind field of the highway and the wind load of the traffic is studied. Two tree species were selected, and the effects of different tree species and arrangement numbers on the wind speed on the embankment and the wind pressure on the driving surface were studied, by simulating the single-row distribution of a single tree species and the mixed multi-row distribution of two tree species. The results show that trees play a significant role in wind field modulation, and different tree species have different effects; Compared with the modulation of single tree species, the mixed modulation effect is more effective, and gradually increases with the number of rows, but the trend of enhancement gradually slows down.
Heavy metal pollution characteristics and assessment of environmental quality and safety of facility agriculture soil in Shouguang
Authors: Zhang J , Xue Q , Chen Q F , Zhao C S , Liu W , Li Q 
Published: January 2021

Abstract
Taking Shouguang Facility agriculture in Weifang City as the research object, heavy metals and other pollutants in new and old facility agriculture soil were investigated and analyzed from 2017 to 2019. The content of heavy metals in soil was analyzed, and the environmental quality of heavy metals was evaluated by single-factor pollution index method and Nemerow index method. The correlation between heavy metal content in surface soil and cultivation years, vertical distribution of heavy metal content in soil, frequency distribution of heavy metal in surface soil, and correlation between heavy metals in surface soil and soil nutrients were analyzed. The results showed that the average contents of the eight heavy metals were Cd 0.23 mg•kg−1, Hg 0.05 mg•kg−1, As 8.09 mg•kg−1, Pb 23.31 mg•kg−1, Cr 70.81 mg•kg−1, Cu 38.54 mg•kg−1, Ni 25.87 mg•kg−1 and Zn 147.52 mg•kg−1. Aside from Pb and Ni, the average content of all other heavy metals in the surface soil of facility agriculture was higher than the average of the control and the geochemical background level of soil in Weifang. Compared with the Environmental Quality Evaluation Standard for Farmland of Greenhouse Vegetables Production (HJ333-2006) and the Soil Environmental Quality Risk Control Standard for Soil Contamination of Agricultural Land (trial) (GB15618-2018), the average content of heavy metals met the standards, with Cd, Hg and Zn content in some samples exceeding the standards. Most surface soil environmental quality is clean or relatively clean, but there is also part of the soil has reached the level of mild or moderate pollution. The content of heavy metals in the soil of the old facility agriculture (cultivation years > 10) was higher than that of the new facility agriculture (cultivation years ≤ 10), and the content of heavy metals in the surface soil (0∼20cm) was higher than that in the deep soil. The quality distribution of heavy metals in the surface soil is affected by exogenous heavy metals, among which Hg and Cd have the largest skewness coefficient and are most affected by exogenous. There was significant positive correlation between heavy metals in surface soil and available phosphorus, hydrolytic nitrogen, available potassium and organic matter. The results indicated that the accumulation of heavy metals in soil was related to the application of organic fertilizer, phosphate fertilizer and compound fertilizer.
Monitoring of soil erosion caused by construction projects using remote sensing images
Authors: Qiu T , Lu F C , Zhang J J , Wang R 
Published: January 2021

Abstract
The application of Remote Sensing (RS) images to soil erosion monitoring caused by construction projects can meet the needs of dynamic supervision and early warning, and can also significantly improve the efficiency of supervision. In this paper, a technical process for monitoring soil erosion caused by construction projects was proposed. As an example, the high-definition RS survey of the whole city of Zhoushan was carried out. Firstly, the contour lines of the protection range determined during the approval of the construction project were vectorized. Secondly, RS interpretation of perturbation patches of construction projects was carried out with the aid of interpretation marks. Thirdly, preliminary judgment of perturbation compliance was made through the spatial overlay of the interpretation results and approved prevention scope. Finally, field investigation was done to correct the results of RS image analysis. The results show that this technical process can interpret the activity status of construction projects, effectively determine the compliance of perturbation conditions, and improve the efficiency of soil-water conservation supervision.
Application of smart waste management in the Department of Civil Engineering, Bali State Polytechnic
Authors: Pertiwi I G A I Mas , Kristinayanti W Sri , Andayani K Wiwin , Aryawan I G M Oka , Putri Indrayanti A A , Sudiarta K 
Published: January 2021

Abstract
The existence of the green campus program is expected to create awareness and concern for the campus community to participate and be responsible for reducing global warming. This research is expected to be a guideline in implementing smart waste management in the Civil Engineering Department of the Bali State Polytechnic in particular to improve quality in the environmental sector. The method of analysis in this research includes: Identification, planning of and quantity of waste generation. The analysis conducted in this study used an analysis referring to several standards regarding green campus, namely UI Greenmetric, Green Guide for University and Greening University Toolkits. Waste management in the Department of Civil Engineering has not carried out processing efforts such as recycling, composting or other integrated efforts. The waste generated from teaching and learning activities, practicum and canteen is carried out by making a reservoir and it is carried out by disposing of waste into the trash bins that have been provided, practicum waste is collected in carts, waste management is carried out in the area of the department such as in the room carried out by cleaning services, which is then the final handling in the campus area, namely garbage is disposed of to the Temporary Landfills (TPS) campus then brought to the Landfills (TPA) by the South Kuta District Sanitation Office. The main objective of the campus solid waste management plan is to maximize resource recovery, with the aim of minimizing the disposal of waste to the TPS. The main strategy is to implement a waste hierarchy by avoiding purchasing products that will eventually become waste, repair and reuse, then recycle, and finally if there is no other choice, disposal to the TPS.
Risk management of Material Laboratory, Department of Civil Engineering, Bali State Polytechnic for preparation of Occupational safety and health program
Authors: Pertiwi I G A I Mas , Aryawan I G M Oka , Kristinayanti W Sri , Andayani K Wiwin , Putri Indrayanti A A , Sudiarta K 
Published: January 2021

Abstract
The purpose of this study is to determine the risks and hazards in the laboratory, it is necessary to identify hazards, risk assessment and risk control. Laboratories are often found in research and development institutions, service companies, industry and universities. The material laboratory is a place to carry out student practicum activities and conduct research which has a source of danger that can cause work accidents such as chemical explosion, fire, poisoning and ext. Work accidents can be avoided by improving the quality of Occupational Safety and Health (OSH) which is related to the process of doing work safely and working conditions that are safe and comfortable. One effort that can help is to identify hazards and risk assessments so that effective control efforts can be made to increase work productivity and reduce work accidents. Hazard identification is a process that can be carried out to identify all situations or events that have the potential to cause work-related accidents and diseases that may arise in the workplace [1]. Carry out hazard identification to answer the question of what potential hazards can occur or befall the company organization and how it can occur. Hazard identification is the first step in developing OSH risk management and a systematic effort to understand the existence of organizational hazards and is the foundation of an accident prevention and risk control program [2].
Numerical investigation of the grooves effect on the inlet flow characteristics and hydraulic performance of an axial-flow pump
Authors: Zhang Rui , Mu Tong , Xu Hui , Qian Xiangdong 
Published: January 2021

Abstract
In this paper, the axial position of the grooves effect on the inlet flow characteristics and hydraulic performance of an axial-flow pump is studied by numerical method. The computational results show that setting the grooves on the pump inlet pipe could significantly improve the inflow characteristics of impeller and the saddle zone would be effectively suppressed. Under the deep stall condition, the grooves could improve the axial velocity of inflow and effectively reducing its streamline bending degree, and it also can block and destroy the vortex structures and then dissipate them rapidly. Reducing the axial distance between grooves and impeller can improve the hydraulic performance and the inflow characteristics of axial-flow pump.
Investigation of the groove effect on the tip leakage vortex flow
Authors: Fei Zhaodan , Zhang Rui , Xu Hui , Mu Tong 
Published: January 2021

Abstract
The groove effect on the tip leakage vortex around a NACA0009 hydrofoil was studied by numerical method. The results show that, as the groove angle is 45°, the groove could enhance the turbulence kinetic energy around the TLV, weaken the TLV strength and improve the pressure in the TLV core, resulting in an efficient suppression effect on the TLV cavitating flow. When the groove angle is 0° and 45°, the groove could decrease the tip leakage flow rate and the TLV gets lower and moves away from the tip gap. As the groove angle is 90° and 135°, the tip leakage flow rate gets larger, and the TLV gets higher and closer to the tip gap.
Non-dimensional study on the start-up process of a centrifugal pump and its related pipe system
Authors: Meng L , Wang W P , Liao C L , Zhao L C , He L , Zhang C Y 
Published: January 2021

Abstract
Hydraulic transient processes sometimes bring with it violent or dramatic unsteady phenomenon, which would interfere the normal operation or even damage the system. The start-up of a centrifugal pump with cavitation can lead to serious transient phenomenon. One dimensional calculation (Method of characteristics) was widely used to solve transient problems, but its drawback is lacking of details for the flow characteristics inside the pump, 3D simulation for transient process simulation needs huge computer resources. A simulation method that coupled MOC and 3D simulation (CFD) was frequently used for solving complex transient problems in these years. The results of the coupling simulation are usually complex when cavitation happens and disappears quickly during the short start-up period, a simplified method to describe the process is necessary. A centrifugal pump and its related system were simulated with a coupling method. Dimensionless mass flow rate, head and cavitation conditions of the pump was used to analyse the start-up process. It was proved that the non-dimensional study method can make the whole process more intuitive and easier to understand.
Calibration of Winter-Kennedy coefficients on a Bulb turbine based on current-meter method
Authors: Cao Dengfeng , Pan Luoping , Zhou Ye , Qu Litao 
Published: January 2021

Abstract
Field measurement of discharge has been performed for a Bulb turbine based on current-method in this paper. Winter-Kennedy coefficients of this machine are calibrated based on the test results of integrated discharge and measured flow differential pressure between bulb head and stay cone. Calibration shows that discharge and flow differential pressure of the test machine follow the power model very well. The uncertainty of discharge estimation by Winter-Kennedy method for Bulb turbine is discussed finally.
Comparison of the effects of leakage flow from guide vanes of different hydrofoils using alternative clearance gap approach
Authors: Gautam Saroj , Lama Ram , Neopane Hari Prasad , Thapa Biraj Singh , Chitrakar Sailesh , Zhu Baoshan 
Published: January 2021

Abstract
Sediments flowing along with water through guide vanes induces abrasive and erosive wear in the GV surface. The effect of these wears differs with the shape of GV profiles. This study presents an alternative clearance gap method to compare the effects of clearance gap (CG) in the GV of Francis turbine with different hydrofoils. Numerical prediction of the performance of Francis turbine with symmetrical and asymmetrical hydrofoils is studied with the CG of 0 mm, 2 mm, and 4 mm thickness. Increase in the size of the gap deteriorates the performance of the runner. In case of asymmetrical GV profile, the effects in the runner is found to be less than the symmetrical profile. It is due to lesser pressure difference between the adjacent sides of the GV profile. With the alternative clearance gap approach, it distinguishes the effect of CG and the pressure pulsation due to rotor-stator interaction for a single numerical model.
Numerical investigation on flow distortion in a vertical inline pump
Authors: Tang Yajing , Si Qiaorui , Gan Xingcheng 
Published: January 2021

Abstract
The vertical inline pump is a centrifugal pump with special structures of curved inlet pipe before the impeller, and it is widely used in where the constraint is installation space. However, the elbow inlet with different angles and cross sections also deteriorates the impeller inflow and results in flow distortion in the impeller. For the purpose of further investigation of flow distortion in the vertical inline pump, the unsteady Reynolds averaged Navier-Stokes equations were solved by the commercial CFD code with the shear stress turbulence model. The normalized coefficients of inlet velocity, pressure, helicity, and non-uniformity were applied to quantitatively analyze the flow distortion in the pump. The computational results showed a great agreement with the experimental results. Under the nominal and overload conditions, the flow separation and counter-vortex pair were found on the outer side of the inlet pipe and the intensity of these phenomenon increases along with the rise of flow rate. However, the flow recirculation was observed under the part-load condition which becomes the major reason for the flow distortion in the inline pump.