bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accurate ground-to-ground laser time transfer by diffuse reflections from tumbling space debris objects
Authors: Liu T , Eckl J J , Steindorfer M , Wang P , Schreiber K U 
Published: January 2021

Abstract
The optical two-way time transfer between two widely separated laser ranging ground stations in common view of a space debris target can be achieved from diffuse laser pulse reflections. The round-trip time-of-flight measurements augmented by the detection and epoch timing of diffusely scattered laser light from the second ground station allows accurate clock comparisons, provided that the mean location of the point of reflection on the target structure can be recovered with sufficient fidelity. We have set up a target delay model that derives the tumbling motion of rocket bodies from a combination of laser ranging and photometric measurements. Combined with the simultaneously measured short arc orbit, we obtain the applicable in situ propagation delay for the time transfer signal between the two ground stations in order to establish the clock offset between them. We show an example where the uncertainty of this clock synchronization for a time-of-flight comparison already reaches 3 ns. We point out that there is still significant room for improvement.
Growth signals determine the topology of evolving networks
Authors: Vranić Ana , Dankulov Marija Mitrović 
Published: January 2021

Abstract
Network science provides an indispensable theoretical framework for studying the structure and function of real complex systems. Different network models are often used for finding the rules that govern their evolution, whereby the correct choice of model details is crucial for obtaining relevant insights. Here, we study how the structure of networks generated with the aging nodes model depends on the properties of the growth signal. We use different fluctuating signals and compare structural dissimilarities of the networks with those obtained with a constant growth signal. We show that networks with power-law degree distributions, which are obtained with time-varying growth signals, are correlated and clustered, while networks obtained with a constant growth signal are not. Indeed, the properties of the growth signal significantly determine the topology of the obtained networks and thus ought to be considered prominently in models of complex systems.
An Ergonomics Approach of The Prayer Mat Size
Authors: Karim Abdul Alimul , Suprapto Sena Sukmananda , Gufron Muhammad 
Published: January 2021

Abstract
Currently, Indonesia does not have a standard size for prayer mats. For this reason, the size of the prayer mat should be designed according to Islamic requirements and laws. This can be done by measuring the human body which is directly related to determining the dimensions of the prayer mat. The length and width of the prayer mat can be determined by knowing the length of the prostration and the width of the shoulders. This research was conducted using an ergonomic approach with anthropometric methods and the cosine formula. This study focuses on male and female adult prayer mats. This research resulted in the length of the prayer mats 1277.12 mm and 1229.1 mm, while the widths of the prayer mats were 805 mm and 744 mm.
Firefly Algorithm for Multi-type Vehicle Routing Problem
Authors: Jamil Ahmad , Abdallah Bayu Nur , Leksono Vridayani Anggi 
Published: January 2021

AbstractThe problem of distribution is a problem that cannot be separated from the industrial world. These problems are because these problems have a considerable influence on the cost and level of service to consumers. Therefore we need a way so that the distribution process can run smoothly and on time. One way that can be done in the distribution process is to optimize vehicle routes so that the time spent serving two consumers is more efficient and the goods can get to consumers on time. The problem of optimizing vehicle routes is known as vehicle routing problem (VRP). VRP which aims to form an optimal route to serve consumers with capacity constraints and Type of Vehicle is called Multi-type vehicle routing problem (MTVRP). In solving the MTVRP problem, two methods will be combined namely the exact method and the heuristic method. The firefly algorithm has been widely used in solving VRP problems. The results are obtained total distance of 2488 km.
Analysis of Using Regularization Technique in The Convolutional Neural Network Architecture to Detect Paddy Disease for Small Dataset
Authors: Mujahidin S , Azhar N F , Prihasto B 
Published: January 2021

Abstract
In some instances, convolutional neural network (CNN) methods such as large numbers of datasets can show very high accuracy. However, in cases such as the small number of datasets, the accuracy performance of CNN often decreases. This also intersects with the constraints of applying CNN to recognize types of diseases in rice with a small number of datasets. This research applied the combination of regularization techniques and CNN methods to recognize rice disease types with a total dataset reaching 120 leaf images. It is found that using CNN-regularization techniques shows better performance than standard CNN architecture. With an accuracy value reaching an average of 85, 878%, it is expected to open further research opportunities.
Evaluation of The Application of Hospital Management Information System (SIMRS) in RSUD Dr. Kanujoso Djatiwibowo Using The HOT-Fit Method
Authors: Setiorini Adani , Natasia Sri R , Wiranti Yuyun Tri , Ramadhan Dean A 
Published: January 2021

Abstract
Hospital Management Information System (SIMRS) is a system that can process and integrate the entire hospital service process flow in the form of a network of coordination, reporting and administrative procedures to obtain accurate data and information. At the RSUD Dr. Kanujoso Djatiwibowo (RSKD) of Balikpapan City, the application of SIMRS experienced problems such as the high number of troubleshooting cases and the redundancy of patient medical record numbers. This case is considered to inhibit the performance of hospital services related to efficiency. Based on this problem, the evaluation of SIMRS in the RSKD was carried out by using the constructed Human, Organization, Technology-Fit (HOT-Fit) model. This model involves eight variables which consists of System Quality, Information Quality, and Service Quality, System Use, User Satisfaction, Structure, and Environment, and Net Benefits. The results indicate that the proposed model either directly or indirectly affects the benefits obtained from implementing the SIMRS. Further implications of the results toward improvement of the system are provided.
Numerical Study of Secondary Flow Characteristics on the Use of the Winglets
Authors: Setyo Hariyadi S P , Sutardi  , Widodo Wawan Aries , Sonhaji Imam 
Published: January 2021

Abstract
The upper surface of the wing is constantly observed by experts on the wing. In this area, a variety of phenomena cause how much aerodynamic performance is demonstrated. Changing or adding geometry to the wing changes the flow characteristics of the upper surface. The use of winglets will certainly change the flow characteristics around the wingtip which will have a large effect on the area behind and next to the winglet itself. This research was carried out using Ansys 19.1 and the turbulent k-ω SST model. The airfoil used is Eppler 562 which is commonly used in unmanned aerial vehicles. Freestream flow velocity that will be used is 10 m/s (Re = 2.34 x 104) with an angle of attack (α) = 12° and 15°. From this study, it was found that the pressure contour in the y-z plane showed a reduction in area and intensity through the use of winglets. Secondary flow formed by using the forward wingtip fence results in a smaller area around the wingtip area than other configurations. Besides, the value of pressure on the upper surface which is equipped with a forward wingtip fence shows that pressure is still quite high when compared to the others.
Simulation of Illipe Butter Purification Originated from West Kalimantan by SuperPro Designer
Authors: Ramadhani Nurul Hikmah , Darmawan Muhammad Arif , Perdana Harahap Andre Fahriz , Arya Ramadhan Muhammad Yusuf , Silalahi Ursula Chriseva , Gozan Misri 
Published: January 2021

Abstract
Tengkawang is one of the commodities of non-timber forest products which has been a life of support for people around the forest. Seeds produced by Tengkawang trees are one of the export commodities. However, unfortunately, the process of exporting Tengkawang seeds abroad often requires a long time to reduce the quality of the Tengkawang seeds. Processing of Tengkawang seeds into oil is a solution to the decline in quality of Tengkawang seeds. Like standard crude vegetable oil, Tengkawang oil also contains impurities. Therefore, a purification process to remove these impurities is needed. This research was conducted to produce purified Tengkawang fat optimally. Purification stages include degumming, neutralization and bleaching. This research will focus on the simulation of purified Tengkawang fat production. In this case, the simulation is carried out as an estimator of the feasibility value roughly whether a fat purification plant can be realized or not.
Kinetic Studies of Methylene Blue Degradation using CaTiO3Photocatalyst from Chicken Eggshells
Authors: Ernawati Lusi , Yusariarta Ade Wahyu , Laksono Andromeda Dwi , Wahyuono Ruri Agung , Widiyandari Hendri , Rebeka Rebeka , Sitompul Virginia 
Published: January 2021

AbstractThis study details the kinetic of photodegradation of methylene blue in aqueous medium using CaTiO3photocatalyst. The CaTiO3catalyst was prepared by sol-gel reaction using CaCO3derived from chicken eggshell and anatase TiO2powder. The CaTiO3particles were prepared using a mixture of starting materials in of (1:1); (1:3); (2:5) and (2:7) CaCO3/TiO2molar ratio at T = 900°C. The physical and microstructural properties of CaTiO3microstructural were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), Fourier Transform Infrared (FTIR) and UV/vis spectrometer. As prepared CaTiO3particles with various composition of CaCO3/TiO2were then applied for removal of dye molecules under simulated UV irradiation. The effect of initial dye concentration, catalyst composition, and degradation time on the adsorption property of CaTiO3was systematically investigated. The results reveal that methylene blue (MB) molecules are efficiently adsorbed and degraded within 120 min using CaTiO3catalysts. Considering the low-cost preparation process and considerably high photocatalytic performance obtained in this work, CaTiO3can further be used as an efficient photocatalyst for organic pollutant removal from industrial wastewater.
Synthesis of Chitosan/Hydroxyapatite Nanofibers as A Wound Dressing via Electrospinning Method
Authors: Fauziyah M , Salsabila T , Setyawan H , Widiyastuti W 
Published: January 2021

Abstract
Nanotechnology had been widely developed for medical application in various forms, either nanoparticles or nanofibers. One of the most attractive use is nanofibers as a wound dressing. An ideal wound dressing should have characteristics of easily sterilized, non-toxic, biodegradable, good oxygen circulation, and anti-microbial performance. Those characteristics could be obtained by using a biomaterial composite which had a good biocompatibility on human body tissues, such as chitosan and hydroxyapatite (HA). Chitosan had an anti-microbial property, while HA could increase the cell generation rate. Therefore, this work would synthesize a chitosan/HA nanofiber as a potential wound dressing via electrospinning method. HA was firstly prepared by electrolysis using alternating electrode configuration. The dope solution of chitosan/HA for electrospinning was prepared by adding polyvinyl alcohol (PVA) as a coadjutant polymer. The morphology of the obtained nanofibers was investigated by SEM. It was revealed that the nanofibers had an average diameter of 261.87 nm which was spun each other forming many pores which was good for oxygen circulation. Therefore, chitosan/HA nanofibers could be a promising material for wound dressing application.
Design of impeller blades in the intermediate stage of centrifugal pump to a preset shape of meridional flow pattern
Authors: Kostornoi A S , Tkach P Yu , Bondariev O O , Podopryhora N N 
Published: January 2021

Abstract
While designing the stages of a centrifugal pump, there is an important and difficult task of impeller blade design. This article deals with an approach to impeller blade design that is based on analytical choice of dependency of flow change along the streamline. The given approach is implemented at JSC “VNIIAEN” in form of custom software which lets the user build a line drawing based on given parameters in normal duty of intermediate stage by designing the blade and calculating the geometrical dimensions of the impeller. The given method has been tested and proven with a physics experiment.
Numerical simulation and experimental investigation of submersible sewage mixer performance
Authors: Błoński D , Szulc P , Machalski A , Rogula J 
Published: January 2021

Abstract
This work focuses on methods of submersible sewage mixer performance evaluation comparison. In the paper an experiment with a submersible mixer with a published and known geometry has been presented. The authors measured thrust, torque rotation speed and electric power. Experiment was compared with results obtained with a steady state numerical simulation. Next CFD results were checked with a theoretical approach for the mixing range. Both theoretical and numerical methods showed good applicability for the industry.
Influence of construction and operating pump parameters on pressure pulsations amplitude
Authors: Sotnyk M I , Moskalenko V V , Strokin O O , Antonenko S S , Sapozhnikov S V 
Published: January 2021

Abstract
The research results that presented in the article are focused on decreasing the intensity of pressure pulsations in the flowing part of centrifugal pumps. The aim of the work is researching influence of changes in construction and/or operating pump parameters on pressure pulsations amplitude. Basing on the research results, were determined the main sources of pressure pulsations in the flowing part of the spiral centrifugal pumps and the reasons of increasing their amplitude during pump operation mode at supply 0.3Qopt…0.7Qopt. The article presents information about dependencies of pump head and pressure pulsations amplitude on construction and operating pump parameters, such as: number of blades (z), blade width at the impeller outlet (b2), ratio of volute initial diameter to impeller outer diameter (D3/D2), angle of output edge inclination (φ), rotor rotation frequency (n) and blades position of impeller halves in relative to each other (shift step - ψ).
Investigation of the operating process of a high-pressure centrifugal pump with taking into account of improvement the process of fluid flowing in its flowing part
Authors: Kondus V Y , Gusak O G , Yevtushenko J V 
Published: January 2021

Abstract
Centrifugal pumps are used in most industries. In particular, they are effectively used in the technological processes of oil production to create reservoir pressure at oil fields. Due to increasing demand for petroleum products, there is a need to improve such pumps to increase reservoir pressure by increasing their pressure. The research considered the possibility of improving the centrifugal pump impeller design by changing its blade system. It is theoretically possible to increase the pump head by changing the blade outlet angle at the impeller outlet β2 to 75°. The design of additional wedge-shaped blades of the second tier of the impeller was developed to reduce some additional hydraulic losses zones. They made it possible to stabilize the fluid flow in the impeller intervane channels, to reduce additional hydraulic losses. In the research, the impeller head was increased up to 26.7% for the proposed design impeller compared to the standard one. The research was performed with a comprehensive analysis of the pump installation life cycle cost. Thus, the development of new ones and the upgrading of pumping installations rooted in the industry with the aim of increasing the head is possible while achieving the minimum pump installation life cycle cost.
The influence of the impeller construction on the performance of one channel pump
Authors: Szulc P , Moliński G , Moloshnyi O 
Published: January 2021

AbstractThe paper presents the comparison of the impeller’s construction on the operating parameters of the sewage pump. Three types of impellers were taken into consideration. The main geometrical parameters were identical, the differences were applied in the meridional cross–section and in the shape of the passages. These three objects of research represent three approaches of the construction of single channel pumps. The analysed impellers were cooperated with the same spiral casing where the flow was identified by means of numerical simulation. The obtained results allow to choose appropriate parameters of the pump in terms of the operating point and shape of the characteristic curves.
Optimal design of vortex chamber pump
Authors: Rogovyi A , Korohodskyi V , Khovanskyi S , Hrechka I , Medvediev Y 
Published: January 2021

Abstract
The difficult operating conditions during the pumping of abrasive solid mediums lead to the rapid wear of the mechanical parts of the pumps. The use of jet pumps can significantly increase the reliability and durability of pumping equipment. However, direct-flow jet pumps have low efficiency. The use of the centrifugal force led to the creation of new jet pumps - vortex chamber pumps. Their performance indicators are better than direct-flow jet pump ones. The geometric parameters of the flow channel of the vortex chamber pumps were optimized. The study was carried out experimentally and numerically. Numerical simulation is based on solving the RANS equations with the shear stress transport turbulence model. The geometrical dimensions of the vortex chamber pump with the best performance indicators such as pressure and flow are found. The maximum achievable operating parameters of the vortex chamber pump are analyzed. The comparison of simulation results with experimental data is made.
Experimental and numerical research on influence of winglets arrangement on vortex pump performance
Authors: Machalski A , Skrzypacz J , Szulc P , Błoński D 
Published: January 2021

Abstract
Vortex pumps are widely used in wide range of hydro-transportation applications. Main disadvantage of this type of pump design is low efficiency. Despite ongoing effort to improve vortex impeller performance precise algorithm for their optimal design doesn't exist. One of the ideas is to use winglets (super-vortex) on the tip of the impeller blades. Conducted literature studies have shown that there is not yet clarified principle of winglet design. Authors have performed numerical simulations and measurements for three different arrangements of winglets with varying impeller coverages. From the obtained results recommendation for optimal winglet placement is deducted.
The numerical simulation of the rope vortex creation and the possibilities of its control
Authors: Szulc P , Machalski A , Skrzypacz J , Blonski D 
Published: January 2021

Abstract
The rope vortex is a phenomena which can be observed in many hydraulic machines, especially turbines and pump–turbines. Its creation is based on a non uniform velocity profile characterized by high value of the circumferential component. This phenomena limits the range of operating conditions, which results in reduction of the energy production. The article presents the flow analysis of the hydraulic Francis turbine, where the rope vortex was observed. The structure of the vortex was identify and some solutions were analysed to prevent or reduce the size of multiphase flow.
The measuring system for air mass flow rate determination - difficult measuring conditions - case study
Authors: Tomaszewski A , Przybyliński T , Lackowski M , Krzemiński E , Rogula J , Romanik G , Błoński D 
Published: January 2021

Abstract
Accurate gas flow measurement is required in many industrial applications. In typical circumstances the most reliable option is the use of single-hole orifice flowmeters, which characterize with the simplicity of the construction, lack of moving parts and high accuracy. However, such devices require long straight duct sections in order to perform the proper measurement. Sometimes on existing installations, where the space is limited, there is no possibility to fulfill these requirements. Such problem appeared in power plant in Opole. Multi-hole orifice flowmeters can be a reasonable solution in this particular case. Due to their enhanced resistance to flow disturbance they require shorter duct sections and could provide a correct measurement. The paper presents the results of the numerical analysis of air flow in 6-hole orifice flowmeter. The calculations were performed for the existing duct geometry from power plant in Opole. The orifice pressure drop was estimated for a wide range of Reynolds number. The analysis of the numerical results showed that multi-hole orifice flowmeters can be used in investigated situation. The results of experimental measurements performed in Opole power plant are also included in the paper.
Effect of front impeller seal leakages on centrifugal stage characteristics
Authors: Andrusiak V O , Lugova S O , Medvid S A , Tkach P Yu , Rudenko A A 
Published: January 2021

Abstract
One of the main criteria in designing a pump unit is its economic efficiency and reliability. The efficiency of the pump is impacted by losses which appear in the pump and can be classified into three categories: hydraulic, mechanical and volumetric. Volumetric losses in centrifugal pumps appear in impeller annular seals and throttling gaps of hydraulic balancing devices. Decreasing clearance in annular seals could, undoubtedly, reduce the volumetric losses and lead to an increase in pumps efficiency. In duties close to optimal, a volume of leakages is almost negligible for the main flow passing through the hydraulic passage. On the contrary, impact of leakages becomes significant at underloaded duties. This article deals with effect of leakages in impeller front seal on efficiency and head-capacity curve.
Analytical study of “crosshead – slide rail” wear effect on pump rod stress state
Authors: Ropyak L Y , Velychkovych A S , Vytvytskyi V S , Shovkoplias M V 
Published: January 2021

Abstract
The work presents an analytical study of “crosshead-slide rail” wear effect on stress state of a double piston pump’s rod. The authors proposed an engineering model of pump’s rod stress state and analytically analyzed a pump rod's stress state caused by wear of the “crosshead-slide rail” pair. It was stated, that wear values according to regulations and directive documents can refer to significant values of rod’s residual stresses. The numerical validation of the obtained results was carried out on for drill pump rods, including reinforced functional coatings.