bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the impact of threats to change and block responses of experts in online survey systems
Authors: Efimov B I , Lozhnikov P S
Published: May 2020

The authors of the article analyze the impact of information security threats when conducting online surveys with an uncertain number of respondents. The article discusses threats to change responses of experts and block responses of experts. Finding the probability of making an erroneous decision using the methods of probability theory is a very difficult task. The authors propose using the Monte Carlo method as a solution. A software module that implements this method has been developed. We obtained the dependence of the probability of making an erroneous decision on the probability of changing the answers of experts, the probability of blocking the answers of experts and the number of respondents. The authors showed that there are critical values for the probability of changes in the responses of experts. These values determine the boundaries of ranges with different characteristics of the dependence of the probability of making an erroneous decision. The authors proposed two methods for finding one of the critical values. In conclusion, the authors formulated conditions that reduce the probability of making an erroneous decision.
Control the movement of an inverted pendulum by using a first-order type Takagi-Sugeno-Kang fuzzy controller
Authors: Kulikova I V
Published: May 2020

The article considers the possibility of using a fuzzy first-order Takagi-Sugeno-Kang type controller to control the movement of an inverted pendulum in order to achieve dynamic stabilization of its unstable equilibrium. The structure of linguistic variables and the base of rules for such a fuzzy controller are proposed. Graphs of changes in the controlled quantities (horizontal carriage displacement and angle of deviation from the vertical) and the control action are constructed, they illustrating the onset of dynamic stabilization of the unstable equilibrium of an inverted pendulum.
On the person and psychophysiological state identification using electroencephalogram parameters
Authors: Nigrey A A , Sulavko A E , Samotuga A E , Inivatov D P
Published: May 2020

The development of methods and technologies for the automatic determination of the psychophysiological state (PPS) of a person is an actual scientific and technical task. Early detection of the fact that the subject is in a sleepy state or in a state of intoxication at the workplace will help to avoid accidents, harm to life, health, and causing losses. In this work the EEG data of 30 subjects in normal, sleepy conditions and a state of mild intoxication were collected. As a result of the spectral and correlation analysis of the EEG data features were selected. An amount of information about the difference of the investigated states contained in the features was determined. A computational experiment on the recognition of human state according to EEG data based on the “naive” Bayes classifier was conducted. The following error level was achieved: 10.9% when recognizing the state of “norm” and “intoxication”; 0.2% when recognizing the status of “normal” and “falling asleep.”
Research of surface morphology of aluminum nitride films obtained by magnetron sputtering method
Authors: Baranova L V , Strunin V I
Published: May 2020

In this paper, we studied the surface morphology of aluminum nitride films obtained by magnetron sputtering intended for use in electronic devices. The main problem with this method of film formation is the large surface roughness of the film; therefore, the task to be solved is to improve the surface quality of aluminum nitride films by smoothing the surface roughness.
Reduction of error and expansion of spatial range of measurement of the electrical field strength sensor
Authors: Biryukov S V , Kolmogorova S S , Kolmogorov A S , Tyukin A V
Published: May 2020

The article is directed to improving the metrological characteristics of the previously investigated multi-element planar electro-induction sensor of the components of the electric field intensity vector. For this purpose, its mathematical model is made and analytic expression is obtained for error taking into account design parameters of sensor responsible for its error in nonuniform field and spatial range of measurement. Using mathematical model, geometric dimensions of sensitive elements of sensor are optimized in terms of minimum error and maximum of spatial measurement range. This allowed the following technical results to be obtained. At optimal parameter b = h/L (h - spacing between edges of sensor and electrode, L-linear dimension of sensor) of sensor error from field nonuniformity does not go out beyond 3% in all spatial range 0 ≤ a ≤ 0.2 (a = L/d; d-distance to field source). Thus, the sensor can be used for measuring at distances from the source of the field d equal to five linear dimensions L (d ≈ 5L).
The influence of a layered-inhomogeneous underlying surface on the antenna pattern
Authors: Yashchenko A S , Krivaltsevich S V
Published: May 2020

The results of works aimed at studying the influence of a flat-layered heterogeneous medium on the type of directional pattern of elementary wave emitter are presented. It was found that a change in the thickness of the frozen soil layer leads to a change in the directional characteristics of elementary emitter. The largest changes in the type of radiation pattern are observed when the thickness of the frozen / thawed layer is a quarter of the wavelength in this medium. It is shown that a change in the type of radiation pattern is also associated with the radiophysical characteristics of the underlying surface on which the antenna is located. The obtained results can be used in the process of optimizing the operation of antenna-feeder devices in conditions of changing the state of the underlying surface.
Approximate kinematic synthesis of the four-bar mechanism by two given positions of the links
Authors: Gebel E S , Chigrinova E A
Published: May 2020

Planar four-bar linkages are widely used in various automatic devices and equipment; therefore, kinematical synthesis methods should be developed in order to reduce the amount of initial data and derived the exact solution using modern mathematical methods. The method of the best quadratic approximation of a function was applied to derive the optimality criterion through the well-known equation for closing a vector contour for four-bar linkage. The obtained mathematical model of kinematical synthesis can be used also to determine the singular positions of the mechanism that can cause a spontaneous change in the law of motion of the output link. Modeling of the proposed kinematical synthesis method using Mathcad confirmed the correctness of the mathematical model and allowed plotting the graphical diagram of connecting rod curves.
Buckling of composite sandwich cylindrical shell with lattice anisogrid core under hydrostatic pressure
Authors: Shatov A V , Burov A E , Lopatin A V
Published: May 2020

Anisogrid structural elements offer significant advantages over conventional stringer-stiffened analogues due to an exceptional strength and stiffness of unidirectional composite ribs, which are used as the main load-bearing elements. The paper presents a numerical solution for buckling of a sandwich cylindrical shell with composite lattice core loaded with hydrostatic pressure. To model the buckling of the shell, the finite element method is used. A parametric analysis on the effect of the number of helical ribs and the orientation angle on the critical hydrostatic pressure is performed. It is revealed that the local, global or coupled buckling modes can be realized in the buckled shell depending on the geometric parameters of the lattice core structure. The parameters at which the shell provides the maximum mass efficiency are determined.
Methods of the analytical construction of diagrams of the vibratory drum vertical movements into the soil for the compacted soil strength assessment
Authors: Tarasov V N , Boyarkina I V , Boyarkin G N , Serebrennikov V S
Published: May 2020

The soil compaction process by a vibratory drum is performed during a slow horizontal progressive movement and high-frequency vertical movements of the vibratory drum by a vibration exciter. Let’s consider the process of a single vertical movement of the vibratory drum into the soil on a horizontal compacted surface. As a result of the vibratory drum progressive movement vertical movements take place on new horizontal areas of compacted soil. The problem of the vibratory drum cylindrical surface vertical indentation into the soil is first presented in a differential form. The stress distribution law as per the soil depth is set taking into consideration the compacted soil layer thickness h
0 and general soil deformation modulus E
0. The relative vertical deformation of elementary soil columns according to Hooke’s law is determined as the ratio of the vertical movement of the vibratory drum elements to the thickness of the layer to be compacted. The analytical integration of equations connecting the vertical load on the vibratory drum with elementary forces of the soil reactions on the vibratory drum bearing surface has been performed. The state of soil strength under the vibratory drum is determined as the initial state σ0 and additional state Δσ, caused by an increase of the soil strength due to the compaction σ=σ0 + εE
0, caused by relative deformation. The problem of the determination of the vibratory drum vertical movement by vertical forces has been solved. Obtained analytical dependences and method allow to construct the dependence diagrams of the vibratory drum movement into the soil on different types of soils. The problem of the vibratory drum vertical movement into the soil has been analytically solved on the basis of the deformation of vertical soil columns in the form of Hooke’s law using the general soil deformation modulus E
0. The vertical interaction of the vibratory drum with the soil has been formulated as the equilibrium problem of the vertical reaction forces along the contact arc. Finite integrals have been obtained connecting the vertical load on the vibratory drum with the parameters of the soil and vibratory drum. The calculation method of the dependence diagrams of loads on the vibratory drum and vertical movements (settlement) of the vibratory drum into the soil has been developed.
Increasing the life of the brush working equipment of a utility vehicle by using a device to control its position
Authors: Tsekhosh S I , Ignatov S D , Demidenko A I , Kvasov I N
Published: May 2020

The article is devoted to the urgent problem of the resource increasing of the brush working equipment of a communal machine. To increase the resource of the brush working body, it is necessary to provide the recommended area of the contact spot of the brush bristles with the surface to be cleaned. This can be done by using a brush position control device. The results of the study of the effect of bristles deformation on the area of contact between the brush working equipment and the surface being cleaned are presented. A variant of the position controlling device of the brush working equipment of a communal machine providing the recommended area of the contact spot between the bristles and the surface being cleaned is proposed. A design diagram of the deformation of the brush working body is presented. As a result of the interaction process analysis between the brush working equipment and the surface being cleaned a relationship is obtained connecting the area of the contact spot with the deformation of the pile. A graph of this dependence is constructed. As a result of the work performed, a relationship is determined that allowing to determine the value of the contact area of the brush working equipment with the surface being cleaned for various values of the bristles deformation taking into account their wear.
Association between thrips and ants on chili and watermelon plants
Authors: Haerul  , Nurariaty A , Nasruddin A , Gassa A
Published: May 2020

Ants have a positive impact on agricultural land as predator on thrips. This study aims to evaluate the association between thrips and ants on chili and watermelon plantations which were conducted in the Maros Regency, South Sulawesi. Samplings of the thrips from the chili and watermelon plants were carried out by using a plastic lid that was placed under the plants, which were then patted by hand until the thrips fall onto the plastic lid and was then counted. The ants were captured using pitfall traps. The results showed that there were two types of thrips, namely Thrips parvispinus and Thrips palmi. The population with the highest average number of thrips was found on farmers’ land averaging at 20.4 thrips, with T. parvispinus averaging at 6.4 thrips/observation and T. plami at 14 thrips/observation. Meanwhile, the lowest average population was found on watermelon plants with only 10.3 thrips/observation with T. parvispinus at 1.1 thrips/observation plus T. plami at 9.2 thrips/observation. The highest ant population was found on chili plants combined with watermelons ie 373.3 ants/observation, while the lowest ant population were found on chili plants on farmers’ land averaging around 104.3 ants/observation. Based on the data, it can be concluded that the ants play a role in reducing the population of thrips.
Statistical Estimation of ideal and realistic muon interaction on Al, Fe, and Cu absorbers
Authors: Norizan M I H M , Hashim I H , Ibrahim F , Ghani N N A M A
Published: May 2020

Interaction of charged muons in various absorbing materials is almost similar to other charged particles. Their behaviour has been observed by various experimental work in material science and nuclear and particle physics. A statistical model is developed in order to study the behaviour of muons after interacting with absorbing material. In this study, ideal and realistic beam structure from high intensity muon facility around the world such as at Japan Accelerator Research Complex, Research Centre Nuclear Physics, Osaka University and Paul Scherrer Institute is assumed. Three absorbing materials (aluminium, iron and copper) with thickness range of 0.00 ˜ 0.12 g/cm2 are used to observe the momentum straggling of the beams. Performance for our model was checked by comparing the value of stopping power with others work for muons with initial kinetic energy of 10-40 MeV with and without including shell effect correction term. The effect of the energy losses towards the beam structure will be discussed.
Development of marine grade radiation cross-linked high density polyethylene (HDPE) floater pontoon material
Authors: Muhammad Sayuti Muhammad Hazim , Razali Meor Yahaya , Abd Rahman Mohd Faizal , Mohammad Shirajuddin Siti Salwa , Ali Mohd Roslie , Mohd On Ahmad Zuhdi
Published: May 2020

Crosslinked High Density Polyethylene (HDPE) was developed using electron beam radiation techniques. The crosslinked HDPE can be used as marine grade cross-linked HDPE floater pontoon material. Thermoplastic resin, HDPE blended with Ethylene Vinyl Acetate (EVA) in various weight percentage compositions before being radiate with electron beams irradiation. These composites showed significant changes in mechanical properties and temperature stability after the irradiations. From this study, the optimum dose for HDPE and HDPE/EVA blends will be obtain. This study also will provide the optimum irradiation dose in order to have a good, high strength and impact for the production of pontoon material. The present of EVA in the blend will act as impact modifier also being investigated in this study. From the study, the result showed some significant changes in thermal and mechanical properties after being irradiated with electron beam. The comparison of the result between these composite composition of irradiated and non-irradiated HDPE composite used for floater pontoon material is presented in this paper
The role of nuclear science and technology (NST) in supporting the implementation of the sustainable development goals (SDGs) in Malaysia
Authors: Rashid F I A , Sali S S M , Kadir A R A , Zolkaffly M Z , Kassim H , Omar M A S , Bakar A Q A
Published: May 2020

The United Nations 2030 Agenda for sustainable development (2030 Agenda) adopted in 2015 has underlined seventeen sustainable development goals (SDGs). The SDGs are used to chart the actions over the next fifteen years (2016-2030) in areas of critical importance for humanity and the planet towards sustainable development. Malaysia is among the countries that have put the SDGs in its development agenda and is on track to achieve the SDGs. Many countries including Malaysia use nuclear science and technology (NST) to meet their development objectives in various areas including food and agriculture, industry, human health, energy, water management, and environmental protection. The use of NST can help to achieve nine of the seventeen SDGs. This paper aims at highlighting the role of nuclear science and technology in supporting the implementation of the SDGs in Malaysia.
Evaluation of default mode network in temporal lobe epilepsy patients and healthy subjects: a preliminary result
Authors: Shuhada JM , Husbani MAR , Hamid A I A , Muhammad AR
Published: May 2020

The default mode network (DMN) is thought to be impaired in epileptic patients, where the functional integrity of its core regions compromised. Fourteen healthy participants and fourteen aged and gender-matched patients with temporal lobe epilepsy (TLE) took part in this study. The resting-state fMRI (rsfMRI) imaging protocol was executed using a 3-T Phillips Achieva MRI scanner at the Department of Radiology, HUSM. The TLE patient displays decreased activation clusters in precuneus and supramarginal gyrus compared to the healthy group. However increased activation clusters were found on middle frontal gyrus, superior temporal gyrus, and angular gyrus compared to healthy subjects. The result from random effects (RFX) on healthy TLE revealed that the left middle frontal gyrus, bilateral superior temporal gyrus, bilateral precuneus, and right supramarginal gyrus were significantly activated but the NOV survive was so small. The findings suggested that TLE patients suffer from impairment in some DMN region, which may cause certain neuropsychological and cognitive degradation.
Internal fire probabilistic safety assessment preliminary work at research reactor TRIGA PUSPATI
Authors: Hashim Zaredah , Kumar Devintharaaj , Zakaria Mohd Fazli , Hussain Mohd Huzair , Sallehudin Mohd Sarif Ahmad Hassan , Maskin Mazleha
Published: May 2020

An internal fire analysis Level-I probabilistic safety assessment (PSA) for TRIGA PUSPATI (RTP) nuclear research reactor was initiated. Previous study on half-scope mode Level-I PSA, focusing only on internal initiating event, were developed for both full power and shutdown operational mode. Hence, in ensuring PSA remains relevant, a subsequent study to kept PSA up to date is a compulsory. The aim of this study is to present the step-by-step work done and the insights gained in identifying and screening significant compartments that are potential to had the worst consequences as an ignition sources. This preliminary study will only focus on RTP’s basement which consist of 3 compartments: switch room, battery room and basement hall. Procedure in data collection were based on IAEA document, Specific Safety Guide No. 3: Development and Application of Level 1 Probabilistic Safety Assessment for Nuclear Power Plants (SSG-3). Microsoft Excel was used as data collection media and internal fire hazard database development. A brief qualitative analysis using failure mode and effect analysis is also presented.
Polarization mechanism and Shockley Read Hall recombination on Quantum Efficiency of InGaN/GaN Blue LED
Authors: Anchal Neha , Sahoo Bijay Kumar
Published: May 2020

InxGa1-x N/GaN blue LEDs faces significant efficiency droop issue. The causes of efficiency droop are Shockley Read Hall recombination (SRH), Auger recombination (AR), carrier delocalization (CD) and electron leakage (EL). The SRH, Auger and electron leakage are functions of carrier concentration and temperature. InGaN/GaN superlattice has polarization electric field at interface. In this work we explore effect of built in polarization (BIP) on efficiency droop. It is shown that polarization field enhances SRH coefficient resulting in more droop in internal quantum efficiency of blue LED. Thus, for improvement in efficiency, polarization field required to be minimized which requires growth of the material in m-plane instead of c-plane.
Effect of temperature on electron leakage and efficiency droop of AlxGa1-xN UV LED
Authors: Sahare Priyanka , Sahoo Bijay Kumar
Published: May 2020

AlxGa1-x N UV LED is a promising light source for water purification, diagnosis and sterilization of medical equipment’s, document authentication, security checking and general lightings. The device suffers from efficiency droop due to a number of factors like Shockley Read Hall recombination (SRH), Auger recombination (AR), electron delocalization (ED) and electron leakage (EL).In this work, effect of temperature on electron leakage and efficiency droop of AlGaN UV LED is investigated. It is found that electron leakage takes place at high injection current and high temperature. Electron leakage can be reduced by minimizing self-heating effect in the AlGaN UV LED.
Influence of defect density and layer thickness of absorption layer on the performance of tin based perovskite solar cell
Authors: Roy Priyanka , Sinha Numeshwar Kumar , Tiwari Sanjay , Khare Ayush
Published: May 2020

The tremendous progress exhibited by Perovskite solar cells (PSCs) within the decade has made PSCs the fastest growing PV cell to date. The PSCs has exhibited increment in power conversion efficiency (PCE from 3.2% to 25.2% within a decade. In PSCs, usually MAPbX3 (X being Cl, Br and I) layer is used as an absorber layer. The incorporation of toxic Lead (Pb) is a matter of concern by some of the researchers. In order to deal with this Tin (Sn) is being used as an alternative of Pb. However, the performance of Sn based PSC still lags behind Pb based PSC. In this work, we demonstrate an efficient Sn based PSC with JSc of 32.6398 mA/cm2, Voc of 0.8946V, FF of 80% and PCE of 23.4%. The results exhibits the potential of Sn based PSCs which is not only efficient but also is environmental friendly. We study the impact of defect density and layer thickness of absorber layer over the performance of Sn based PSC. An analysis on the effect of doping in Electron Transport Layer (ETL) and Hole Transport Layer (HTL) over the performance of Sn based PSC is also conducted.
A First principle study of structural and electronic properties of ZnO and ZnS Buckyball structures
Authors: Sharma Sakshi , Shrivastav A K , Oudhia Anjali , Verma Mohan L
Published: May 2020

The nanostructured ZnO and ZnS in Buckyball form have been optimized using first-principle density functional (DFT) approach. For an improved understanding of the systems, investigation of their structural and electronic properties are performed. Study of Density of states (DOS) and partial density of states (PDOS) are carried out. The system obtained a well near reported values of energy and bond length, done previously. DFT study was found to be very much compatible with the theories of solid-state physics. This study provides a good comparison between the properties of ZnO and ZnS buckyball structures, which is reported for the first time. The study may be useful for group II-VI elements based applications on various fields such as OLEDs, Photovoltaics, sensors, biomedical applications etc.
Structural, Electrical and Magnetic Properties of Mechanothermally Synthesized Bi (Co0.45Ti0.45Fe0.10)O3 Nanoceramic
Authors: Kumar Nripesh , Shukla Alok , Kumar Nitin
Published: May 2020

High-energy ball mill was exploited to synthesize Bi(Co0.45Ti0.45Fe0.10)O3 nanoceramic, followed by solid-state cramicmethod. XRD (X-ray diffraction), SEM (scanning electron microscopy) and impedance spectroscopy methods were exploited to analyze elementary crystal structure, micrograph and comprehensive electrical characteristics of the as -synthesized nanoceramic. The impedance spectroscopy technique offered many exciting outcomes on the influenceof grain and grain boundary on the total resistiveproperties of the nanoceramic. The trend of frequency dependence of a.c. conductivity follows Jonscher's power law. The upgraded conductivity and dielectric property propose various applications in the embedded capacitors. PE loop tracer and VSM (Vibrating sample Magnetometer) were exploited to study the ferroelectric and magnetic characteristics of the synthesized nanoceramic. The B-site modified BiFeO3 (with Co and Ti) exhibit ferroelectric and magnetic behavior at room temperature.
Parametric uncertainty quantification in natural frequency of sandwich plates using polynomial neural network
Authors: Karsh P. K. , Raturi H. P. , Kumar R. R. , Dey S.
Published: May 2020

In this paper, uncertainty quantification in natural frequencies for laminated soft core sandwich plates is presented by employing finite element (FE) coupled polynomial neural network (PNN) approach. The computational efficiency and accuracy is achieved by using PNN as surrogate model. Latin hypercube sampling method is employed for training of data in PNN model. The stochastic first three natural frequencies of sandwich plates are studied for individual variation in input parameters. The stochasticity in individual input parameters are considered in order to assess their influence on global response of the structure. The algorithm discussed in this article is observed to be converging with the previously published literature (for deterministic case) and validated with full scale Monte Carlo simulation (MCS) i.e. original finite element approach (for stochastic case). The computational time and cost reduced significantly by employing the present surrogate based FE approach compared to that of conventional Monte Carlo simulation approach.
Three dimensional natural transform and its applications
Authors: Sinha Arvind Kumar , Panda Srikumar
Published: May 2020

We have discussed the concept of three dimensional natural transform and its applications in material science. We have solved the particular type of third order partial differential equations (known as Mboctara equation) using the three dimensional natural transform operator.
Study of the Radiotherapy Treatment Margins in Prostate Cancer with Fuzzy Logic Model
Authors: Patnaikuni S K , Saini S M , Chandola R M , Choudhary V
Published: May 2020

Start your abstract here…External beam radiation therapy (EBRT) is a process in which therapeutic radiation dose is delivered to targettissues whilst seeking the risk of healthynormal and critical organs is minimal. In case of Complex radiation therapy technique such as volumetric modulated arc radiotherapy (VMAT), there is requirement of precise and optimal treatment margin selection so that not only the resulting dose distributions gives high tumor control probability(TCP) but also dose close to critical organs will get minimal. A fuzzy logic application was used here to derive the optimal radiotherapy treatment margins to be used in radiation therapy treatment planning. Here major all possible radiotherapy uncertainties accounted such as translational set-up, organdelineation and organ motion-induced errors for calculating the quantitative variations in target volume radiobiological parameters for treatment plans using fixed step sized increments of treatment margins up to maximum possible variations of tumor volumes. Therules and membership functions were adopted from dosimetricresults of treatment planning for the fuzzy inference system. The imprecision and smoothness of the original fuzzy output was corrected with application of a convolution technique. The results demonstrate that performance of the applied fuzzy model margins against current used radiotherapy margins was consistent inlower range of error magnitude but beyond that a significant non-linearly margin performance was found when considering the normal tissue complication probability (NTCP) and constraint factors into account in the margin recipe formulation. With the new margins obtained then applied for the study of prostate cancer treatment planning and results were compared well with current volumetric modulated arc radiotherapy (VMAT)technique.
Impregnation of lumber due to the pressure of the impregnating liquid
Authors: Birman A , Svoykin F , Neslukhov V , Borozna A , Taraban M
Published: May 2020

Storage of the container is one of the most serious problems faced by the manufacturer. At temperatures above 5 °C, the fungus and blue stain affect the container board. Because of this, enterprises suffer losses, which most often occur due to the fact that customers reject wooden containers, since it is important to use wooden pallets without mold and mildew in food and packaging industries. The article describes the methodology and results of experimental studies on the impregnation of wood due to the hydrostatic pressure of the impregnating liquid. Graphic dependencies are made to determine the main technological parameters of the impregnation process - its duration. We studied wood samples of spruce, birch, alder and aspen, the main species from which container sets and pallets are made. A description is given of the use of a densitometer of a fundamentally new design, which makes it possible to determine the density of samples with positive buoyancy.
Study of intra-day dynamics of currents in the area of the navigable strait of Baltiysk to adjust the movement of water transport
Authors: Istomin E , Martyn I , Petrov Y , Stepanov S , Sidorenko A
Published: May 2020

The aim of this work is to determine the characteristics and dynamics of flows navigable waters of the Vistula lagoon, strait of Baltiysk and coastal areas of the Baltic sea. The research was conducted by employees of the Russian State University together with employees of Shirshov Institute of Oceanology of the Russian Academy of Sciences (IO RAS) at release of drifters on the water area of the sea strait with the subsequent processing of the received GPS data with visualization in the MapSource program. The study in the Baltic sea canal was the regularities of traffic flow, identified certain intra-day dynamics of a course, significantly dependent on wind conditions over the water area. In the course of the work performed, an almost complete intra-day analysis of currents in the Baltic shipping strait area was carried out.
On the question of the mechanism of dust cloud formation on forest roads
Authors: Motovilov B P , Zubova O V , Borozna A A , Motovilov G K , Skachek D A
Published: May 2020

The justification of the model of dust cloud formation during the passage of a forest train on a dry road surface is given. Given the previous studies on sedimentation of single particles and a dust cloud, a formula is obtained that allows one to calculate the initial and average sedimentation velocity of a dust cloud taking into account changes in the concentration of dust in the cloud.
Mathematical model for defining peak loads in hydraulic manipulator’s joints
Authors: Sidorenkov N , Martynov B , Andronov A , Taraban M
Published: May 2020

The main component which plays the key role in any cargo lifting machine is a hydraulic manipulator (HM). At the moment our factories manufacture a whole variety of HM, the main disadvantage of which is a short life span (3 to 5 years at full capacity). In order to increase the life span of a HM it is compulsory to continuously control peak load indicators during its utilization, therefore defining the optimal maintenance periods for the machinery. For controlling the technical condition of assembles and connections, non-dismantle methods of diagnostic are being used. The most perspective of them is the method of vibration measurement. The mathematical model of calculating peak shock loads, appearing if HM connections at the initial time and their relation to diagnosis parameter (vibration amplitude) is presented in the following article, frequency range of shock load is defined.
Optimization of forest road network layout problem
Authors: Simonenkova A , Simonenkov M , Bacherikov I
Published: May 2020

The article describes a three-stage hierarchical method of solving the optimization of forest road network layout problem taking into account road construction and transportation costs using a mathematical model based on the multi-commodity flow model. Optimization of the forest road network layout problem is formulated as an alternative of the Steiner tree problem in graphs. The first stage involves optimization of the forest road network layout within clusters. Many harvesting areas have already been divided into clusters using a clustering optimization model. The second stage involves solution of the similar problem between clusters. At the third stage, the final optimization is performed based on the results obtained at the first two stages. The developed methodology of heuristic solution of optimization of forest road network layout problem allows to improve solving time by 3-6 times with a deviation from the optimal result in the range of 0.5-8%.
Classification of factors influencing the reliability of the driver-vehicle-road-environment (DVRE) system in the conditions of mountain quarries
Authors: Umirzokov A M , Mallaboev U M , Saidullozoda S S , Khabibullozoda Kh Kh
Published: May 2020

The article provides a classification of factors affecting the efficiency of the DVRE system in operating conditions in mountain quarries. A detailed classification of factors affecting the reliability of mining heavy-duty dump trucks operating in mining quarries for such groups of features as design, technological, operational and road-climatic is provided. In addition, the article provides a classification of factors based on controllability. To assess the influence of the stochastic nature of external influences that determine the dynamics of the interaction of the vehicle with the roadway, rational methods based on probability theory are substantiated. Three of them are recommended for an adequate assessment of the influence of external influences on the output indicators of a career heavy-duty dump truck, in particular for evaluating the process of interaction of a vehicle with a roadbed, which is probabilistic in nature. Among the recommended estimation methods are included such as the method of approximating the external load with a periodic function such as a sinusoid with certain values of the amplitude and period of oscillation, the method of expanding the periodic function in Fourier series and the probabilistic-statistical method, which is based on taking into account the action of many random factors characterized by a stable frequency.
Effect of Moringa oleifera leaf powder in diets on laying hens performance, β-carotene, cholesterol, and minerals contents in egg yolk
Authors: Bidura IGNG , Partama IBG , Utami IAP , Candrawati DPMA , Puspani E. , Suasta IM , Warmadewi DA , Okarini IA , Wibawa AAP , Nuriyasa IM , Siti NW
Published: May 2020

The present study was designed to investigate the influence of Moringa oleifera on Laying Hens Performance, β-carotene, cholesterol, and minerals contents in egg yolk. Two hundred and forty 30 weeks of healthy laying hens with homogeneous body weight in a complete randomized design with four treatments and 6 replications. Laying hens were randomly divided into four groups: M0: diets without administration of Moringa oleifera leaves, M1: diets with 2% Moringa oleifera leaves; M2: diets with Moringa oleifera leaves 4%; and M3: diets with 6% Moringa oleifera leaves, respectively. Each treatment consisted of six replication cages with 10 birds randomly assigned to each cage. This study showed that administration of the Moringa leaves powder were increased significantly different on egg productions, egg mass, feed efficiencies, yolk color, shell thickness, Mg and Ca contents in eggshell, but not the efficiency of feed consumption. The administration of 2-6% Moringa leaves powder in diets results in significantly lower yolk cholesterol contents. It was concluded that supplementation of 4-6% Moringa leaves powder in diets, increased egg production, egg mass, feed efficiencies, yolk color, shell thickness, β-carotene, Mg and Ca contents in the yolk, but decreased yolk cholesterol contents in laying hens.
Producing drop-in biofuel from feedstock grown on marginal land in Sumba island, Indonesia: a systems dynamics analysis
Authors: Lamria M , Sims R E H
Published: May 2020

To improve sustainability, liquid biofuel can be produced by growing biomass feedstock on marginal land and using innovative and appropriate conversion technology under development. Throughout the Indonesia Archipelago, oil fuel imports are high, and marginal land is abundant. This study assessed future potential for drop-in biofuel (DBF) production from Pongamia pinnata oilseed crops as driven by various policy and technical parameters. A systems dynamics approach was applied and a model developed to simulate the dynamics of developing DBF technology at the national level. The potential use of marginal land in Sumba Island was taken as a case study to assess the projected DBF production as well as any increase in the gross regional domestic product (GRDP) by 2045. The model outputs showed there is an inter-relationship between biofuel development and political elements, especially the level of sense of urgency (SU) by the country’s President. In enhancing DBF production, and hence increasing GRDP, SU can be increased and sustained by empowering a future vision for the nation. Given a maximum future vision over time, 100% of liquid fuel self-sufficiency could be reached in Sumba by 2033. Then the GRDP increased from DBF-related revenues would exceed the current total GRDP.
Extraction of polyunsaturated fatty acids to reduce the iodine number of biodiesel products
Authors: Helwani Z , Umar L , Neonufa G F. , Puspawiningtyas E , Prakoso T , Lugito G
Published: May 2020

In the last ten years, Indonesia has succeeded in realizing the production and commercialization of oxygenated biofuel/bioethanol and bioethanol, even has applied mixing biodiesel into diesel to up to 20%-volume (or known as a B20 mixture). This success has at least helped reduce imports of fuel oil (BBM) such as diesel and gasoline, but no more than 20%. The rest (i.e., at least 80%) must still be imported and will cause severe pressure on the country’s balance of payments because the current volume of fuel imports is no less than 50% of domestic needs. The quality of Indonesian biodiesel products generally still has a high cloud point and low oxidation stability. Diesel engine fuel consists of a mixture of methyl ester fatty acids (FAME: Fatty Acids Methyl Ester). Many constituent components are limited or not large (consist of 7-14 carbons). The essential constituents are the methyl esters of lauric, myristic, palmitic, stearic, oleic, linoleic, and linolenic acids. Methyl esters of polyunsaturated fatty acids (linoleic, linolenic, eleostearic) are inferior because they have a low cetane number and low oxidative stability. While methyl esters of saturated fatty acids have a superior demonic rate but have a high melting point (bad, higher than the requirements given by SNI). Related to the amount of unsaturated fat in biodiesel, it can reduce the quality of biodiesel, such as acid numbers, moisture content, and the emergence of sludge. Based on the current condition of biodiesel quality, to improve the quality of biodiesel produced can be done by reducing the number of unsaturated fats present in the biodiesel product. The initial step that has to be done is separation biodiesel products into saturated biodiesel with the characteristic iodine number <30-40 and unsaturated biodiesel with an iodine number > 70 through a fractionation process. Extraction was carried out using AgNO3 with variations in the ratio of biodiesel feed to solvents. The best ratio of biodiesel:AgNO3 to eliminate the levels of polyunsaturated free fatty acids in biodiesel products is 1:2 with an iodine value of 47.38 gr I2/(100 gr oil)
Production of biofuel by low temperature Fischer-Tropsch using Co-K/γ-Al2O3
Authors: Makertihatha I.G.B.N , Fadhli  , Fathoni Zaki Al , Subagjo
Published: May 2020

Fischer Tropsch is a heterogeneous catalytic chemical reaction which converts a mixture of hydrogen and carbon monoxide (syngas) into a hydrocarbon product with varying chain length by polymerization reaction on the surface of the catalyst. The hydrocarbon produced from Fischer Tropsch reaction using bio-syngas is biofuel (diesel, kerosene, gasoline) that can replace petroleum-based fuels. Cobalt catalyst with potassium promoter and γ-Al2O3 support has been successfully synthesized in Catalysis and Reaction Engineering (CaRE) laboratory, Institut Teknologi Bandung (ITB). Co-K/γ-Al2O3 catalyst was prepared by dry impregnation method on the γ-Al2O3 support under alkaline conditions. Catalysts were characterized using X-Ray Diffraction (XRD), temperature program reduction (TPR), and N2 physisorption measurements such as Barrett-Joyner-Halenda (BJH) and Brunauer-Emmett-Teller (BET) methods. Co-K/γ-Al2O3 catalyst activity was evaluated using fixed bed reactor with various flow rates and temperatures which is still classified as Low-Temperature Fischer Tropsch (LTFT) process. The best results were obtained at minimum syngas flow rate and highest reaction temperature with a total pressure of 20 bar. The results show CO and H2 conversions were 96.6% and 82.31% respectively. Selectivity value of the hydrocarbon product was calculated using the Anderson Shultz Flurry (ASF) equation. The greatest selectivity value was obtained for C5+ product with selectivity value was 86.07 % wt.
Tauc Plot Software: Calculating energy gap values of organic materials based on Ultraviolet-Visible absorbance spectrum
Authors: Johannes Albert Zicko , Pingak Redi Kristian , Bukit Minsyahril
Published: May 2020

Studies on bio-organic materials for optoelectronic devices have increased recently, mainly due to the low cost of the materials. Electrical properties of the materials are important to review whether a material is suitable for optoelectronic applications. The energy gap is an important parameter to investigate the electrical properties of materials, and therefore, the band gap value has to be determined accurately. The energy gap of a semiconductor material can be calculated from its absorption spectrum using the Tauc plot method. In this article, we designed software based on the Tauc plot method (Taucplot4dotz) and ran a trial test using data from our previous studies on Sukun (Artocarpus Altilis) leaves extract and Gamal (Gliricidia Sepium) leaves extract. Results obtained were more accurate than our previous calculations since here we used both horizontal dan vertical linear extrapolation lines compared to only one in our previous calculations. We also used re-fitted data of ZnO [26]. Our accurate and fast calculation using the software showed that energy gap values of Sukun leaves and Gamal leaves extract were 3.033 eV and 1.833 eV, respectively. For ZnO, the energy gap was found to be 3.6205 eV, slightly different from the original data (3.625 eV) [26]. From the results, it can be concluded that the software provides an easier and faster calculation of energy gap values of materials, from which one can further investigate the potential of the materials suitable for optoelectronic devices based on bio-organic materials.
Coating of mercapto modified silica on iron sand magnetic material for Au(III) adsorption in aqueous solution
Authors: Karbeka Martasiana , Nuryono  , Suyanta
Published: May 2020

The functionalized silica coating mercapto on iron sand magnetic material (MM/SiO2/MBI)has been done through sol-gel process. The successfully synthesized material is used as adsorbent (MM/SiO2/MBI) in the Adsorpi Au (III) process. Material characterization is carried out with an adsorbent stability test against acids. Adsorption is performed in a batch system and the unadsorped Au (III) ion is analyzed with the Atomic Absorption Spectrophotometer (AAS). Characterization results indicate the synthesis of PB/SiO2-MBI adsorbent has been successfully performed. The coating of iron sand magnetic material enhances stability to acid. ADsorbent (MM/SiO2/MBI) is capable of adjudisorate ion Au (III) with the highest adsorption occurring at pH 1. Kinetics review indicates that the adsorption of the ion (III) is following the second-order pseudo kinetics with a value of k 3.57 × 10-3 g/mg. Minute and adsorption isotherm follows the isotherm pattern of Langmuir with an adsorption capacity of 125 mg/g.
The influence of Ag concentration on the antibacterial properties of plastic made from silica immobilized with EDTA-Ag combined with chitosan
Authors: Wogo Hermania Em , Tanuab Marini T. , Kadang Luther , Ola Antonius R.B.
Published: May 2020

Antibacterial plastic is made by using composites silica gel immobilized EDTA-Ag combined with chitosan. Silica gel was formulated with three variations of Ag concentrations (i.e., 10-3, 10-4, and 10-5 M) and then tested for its antibacterial activity against Escherichia coli and Staphylococcus aureus. Result of the antibacterial test showed that the immobilized EDTA-Ag silica gel product could inhibit the growth of Staphylococcus aureus and Escherichia coli with the diameter of zone inhibition around 15.9 and 15.6 mm respectively at the lowest Ag concentration of 10-5M. This result showed that higher concentration of Ag led to the decrease of antibacterial activity. The obtained products were then synthesized into plastic with variations of chitosan weight of 0.3 and 0.7 grams. The antibacterial test confirmed that the plastic had strong antibacterial properties with the diameter of zone inhibition for Staphylococcus aureus and Escherichia coli was 16.7 and 15.9 mm, respectively. The percentage of degradation was observed at 6.02 to 63.17% while water absorption test for plastic with 0.3 gram chitosan was 86.51% and for plastic with 0.7 gram chitosan was 16%. This indicated that more chitosan additions were able to expand antibacterial properties and reduce the absorption of plastic against water.
The effect of cationic CTAB surfactants on the performance of graphene electrode for supercapacitor
Authors: Nurdin I , Fitri H R , Widiatmoko P , Devianto H , Prakoso T
Published: May 2020

Graphene is a two-dimensional sp2 bonded carbon nanostructure packed in a honeycomb crystal lattice. Graphene has a high theoretical surface area and electrical conductivity that is suitable for the electrode of supercapacitors. There are many methods to produce graphene, such as mechanical exfoliation using scotch tape, reduction of graphene oxide, and chemical vapor deposition. An alternative and simple method to produce graphene is through pyrolysis process. The previous study shows that the production of graphene from biomass via two-stage pyrolysis process results in an increase of the surface area; however, its capacitance is still low to be applied as the electrode for supercapacitor. This study aims to modification of graphene surface using cetyltrimethylammonium bromide (CTAB) as the surfactant. The graphene was produced from palm kernel shell via two-stage pyrolysis method (the first stage was at 350°C followed by the second stage at 900°C) using FeCl3 as catalyst and ZnCl2as activating agent, resulting in 16% yield. Graphene was analyzed using Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), Raman scattering, X-ray Diffraction (XRD), and Fourier Transform Infrared (FTIR). These analyses show that the two-stage pyrolysis produces multi-layered graphene. The surface properties were analyzed by nitrogen adsorption-desorption measurements, which show some mesoporous graphene product with a surface area of 351.27 m2/g. The result exhibited more hydrophilic graphene than the unmodified one, but according to the Cyclic Voltammetry (CV) analysis, the specific capacitance of modified graphene (11.91 Fg-1) is lower than unmodified graphene (43.87 Fg-1).