bluuebunny/crossref_metadata_2025 huggingface dataset:
Fast self-testing quantum random number generator based on homodyne detection
Authors: Rusca Davide , Tebyanian Hamid , Martin Anthony , Zbinden Hugo
Published: July 2020

Self-testing and semi-device independent protocols are becoming the preferred choice for quantum technologies, being able to certify their quantum nature with few assumptions and simple experimental implementations. In particular, for quantum random number generators, the possibility of monitoring, in real time, the entropy of the source only by measuring the input/output statistics is a characteristic that no other classical system could provide. The cost of this possibility is not necessarily increased complexity and reduced performance. Indeed, here we show that with a simple optical setup consisting of commercially available components, a high bit generation rate can be achieved. We manage to certify 145.5 MHz of quantum random bit generation rate.
Role of uncertainty estimation in accelerating materials development via active learning
Authors: Tian Yuan , Yuan Ruihao , Xue Dezhen , Zhou Yumei , Ding Xiangdong , Sun Jun , Lookman Turab
Published: July 2020

An active learning strategy using sampling based on uncertainties shows the promise of accelerating the development of new materials. We study the efficiencies of the active learning iteration loop with different uncertainty estimators to find the “best” material in four different experimental datasets. We use a bootstrap approach aggregating with support vector regression as the base learner to obtain uncertainties associated with model predictions. If the bootstrap replicate number B is small, the variance estimated by the empirical standard error estimator is found to be close to the true variance, whereas the jackknife based estimators give an upward or downward biased estimation of variance. As B increases, the bias of the jackknife based estimators decreases and the variance estimated finally converges to the true one. Therefore, the empirical standard error estimator needs the least number of iteration loops to find the best material in the datasets, especially when the bootstrap replicate number B is small. Our work demonstrates that an appropriate Bootstrap replicate B is conducive to minimizing calculation costs during the materials property optimization by active learning.
Three-dimensional printing of diamagnetic microparticles in paramagnetic and diamagnetic media
Authors: Ghosh Dibyendu , Gupta Tamaghna , Sahu Rakesh P. , Das Prasanta K. , Puri Ishwar K.
Published: July 2020

We present an analytical model that explains the motion of finite-size diamagnetic particles in paramagnetic or diamagnetic fluid media. Our model problem is the magnetic field-assisted three-dimensional assembly of carboxylate microspheres in a gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) solution that is placed in a cuboid. The trajectory of each microparticle is determined through a time marching solution of its equation of motion. The effects of the (1) magnetic field distribution and (2) magnetic susceptibility of the paramagnetic solution, which depends on the Gd-DTPA concentration, on the dynamics of particle assembly are identified. Validation of the analytical model is provided through experimental measurements. For the first time, we demonstrate that it is possible to form structures of diamagnetic particles in diamagnetic fluid media, for which we select the assembly of graphene in water.
Magnetically induced topological transitions of hyperbolic dispersion in biaxial gyrotropic media
Authors: Tuz Vladimir R. , Fesenko Volodymyr I.
Published: July 2020

Magnetically induced topological transitions of isofrequency surfaces of bulk waves propagating through an unbounded biaxial gyrotropic medium are studied. The medium is constructed from a two-component superlattice composed of magnetized ferrite and semiconductor layers. To derive the constitutive parameters of the gyrotropic medium, a homogenization procedure from the effective medium theory is applied. The study is carried out in the frequency range near the frequency of ferromagnetic resonance, where the magnetic subsystem possesses the properties of natural hyperbolic dispersion. The topological transitions from an open type-I hyperboloid to several intricate hyperbolic-like forms are demonstrated for the extraordinary waves. We reveal how realistic material losses change the form of isofrequency surfaces characterizing hyperbolic dispersion. The obtained results broaden our knowledge on the possible topologies of isofrequency surfaces that can appear in gyrotropic media influenced by an external static magnetic field.
Notes on the diets of four rodent species from Goodenough Island
Authors: Elliott Todd F. , Vernes Karl
Published: July 2020

Goodenough Island is in the Milne Bay Province of Papua New Guinea and is located off of New Guinea’s eastern coast. Goodenough Island has a unique yet poorly studied mammal community. Previous dietary study of mycophagous New Guinean forest wallabies showed that Goodenough Island’s endemic black forest wallaby (Dorcopsis atrata) ate at least 12 taxa of fungi. Using spirit collections at the Australian Museum in Sydney, we evaluated and compared fungal diversity in rodent diets on the same island. We sampled diets of four Goodenough Island rodent species (Chiruromys forbesi, Paramelomys platyops, Rattus exulans and Rattus mordax) and show that fungi are dietary components for three of these mammals.
HealthPathways: a detailed analysis of utilisation trends in the northern Sydney region
Authors: Lind Kimberly E. , Jorgensen Mikaela , Stowers Chanelle , Brookes Martyn
Published: July 2020

This study developed a model for using Google Analytics (GA) data to evaluate utilisation trends of the Sydney North HealthPathways portal. HealthPathways GA data merged with dates of page localisations and promotional events from March 2017 through June 2018 were analysed to evaluate engagement and use of HealthPathways, integration into clinical practice and how HealthPathways is used. Descriptive statistics and plots were generated for each clinical stream and page for the number of users per month (total, new and return users), mean time on page, navigation and search terms. The number of page views, new users and return users increased during the study period. Each clinical stream had between 26 and 2508 views, with a median of 199 views (interquartile range 84–461 views). Individual pages had 0–12388 total views. Return users visited seven times on average. Most usage occurred between mid-morning and mid-afternoon. Diabetes was the most frequently viewed and searched clinical stream, followed by palliative care. These streams had the greatest number of promotional events. Increasing use of and interaction with HealthPathways suggests that it is a useful tool to support clinical practice among northern Sydney primary care providers.
Emergent scenario in mimetic gravity
Authors: Huang Qihong , Xu Bing , Huang He , Tu Feiquan , Zhang Ruanjing
Published: July 2020

The emergent scenario provides a possible way to avoid the big bang singularity by assuming that the Universe originates from an Einstein static state. Therefore, an Einstein static Universe stable under perturbations is crucial to a successful implementation of the emergent mechanism. In this paper, we analyze the stability of the Einstein static Universe against the scalar perturbations in the mimetic theory and find that stable Einstein static solutions exist under certain conditions in this theory. In the original mimetic gravity, the Einstein static Universe is unstable. Then, we find that the Universe can naturally exit from the initial static state, evolve into an inflationary era and then exit from the inflationary era. Thus, the emergent scenario can be used to resolve the big bang singularity in the mimetic theory.
Core-hole localization and ultra-fast dissociation in SF6
Authors: Ekholm V , Chiuzbǎian G S , Såthe C , Nicolaou A , Guarise M , Simon M , Jaouen N , Lüning J , Hague C F , Gel’mukhanov F , Odelius M , Björneholm O , Rubensson J-E
Published: July 2020

Resonant inelastic x-ray scattering spectra excited at the fluorine K resonances of SF6 have been recorded. While a small but significant propensity for electronically parity-allowed transitions is found, the observation of parity-forbidden electronic transitions is attributed to vibronic coupling that breaks the global inversion symmetry of the electronic wavefunction and localizes the core hole. The dependence of the scattering cross section on the polarization of the incident radiation and the scattering angle is interpreted in terms of local π/σ symmetry around the S–F bond. This symmetry selectivity prevails during the dissociation that occurs during the scattering process.
Experimental artifact in MOKE measurements when using paramagnetic sample holders
Authors: Muñoz-Noval A , Bonin C J , Bonetto F , García M A
Published: July 2020

We describe here an artifact that may affect to magneto-optical Kerr measurements. When paramagnetic sample holders (SH) with non-negligible susceptibilities are used, the inhomogeneity of the applied magnetic field can induce forces and torques on it, shifting the reflected beam, and altering its intensity at the photodetector. The effect is even and can be avoided using low susceptibility paramagnetic or diamagnetic SH We also present a detailed analytical description of the magnetic forces involved and provide some estimated values of the SH shifting, showing that they might distort the magneto-optical Kerr effect signal. Moreover, in this paper we show how the artifact can be removed from the experimental curves with an appropriated data analysis.
On optimal coupling of the ‘electronic photoreceptors’ into the degenerate retina
Authors: Werginz Paul , Wang Bing-Yi , Chen Zhijie Charles , Palanker Daniel
Published: July 2020

Objective

To restore sight in atrophic age-related macular degeneration, the lost photoreceptors can be replaced with electronic implants, which replicate their two major functions: (1) converting light into an electric signal, and (2) transferring visual information to the secondary neurons in the retinal neural network—the bipolar cells (BC). We study the selectivity of BC activation by subretinal implants and dynamics of their response to pulsatile waveforms in order to optimize the electrical stimulation scheme such that retinal signal processing with ‘electronic photoreceptors’ remains as close to natural as possible.

Approach

A multicompartmental model of a BC was implemented to simulate responses of the voltage-gated calcium channels and subsequent synaptic vesicle release under continuous and pulsatile stimuli. We compared the predicted response under various frequencies, pulse durations, and alternating gratings to the corresponding experimental measurements. In addition, electric field was computed for various electrode configurations in a 3-d finite element model to assess the stimulation selectivity via spatial confinement of the field.

Main results

The modeled BC-mediated retinal responses were, in general, in good agreement with previously published experimental results. Kinetics of the calcium pumps and of the neurotransmitter release in ribbon synapses, which underpin the BC’s temporal filtering and rectifying functions, allow mimicking the natural BC response with high frequency pulsatile stimulation, thereby preserving features of the retinal signal processing, such as flicker fusion, adaptation to static stimuli and non-linear summation of subunits in receptive field. Selectivity of the BC stimulation while avoiding direct activation of the downstream neurons (amacrine and ganglion cells—RGCs) is improved with local return electrodes.

Significance

If the retinal neural network is preserved to a large extent in age-related macular degeneration, selective stimulation of BCs with proper spatial and temporal modulation of the extracellular electric field may retain many features of the natural retinal signal processing and hence allow highly functional restoration of sight.
BCI for stroke rehabilitation: motor and beyond
Authors: Mane Ravikiran , Chouhan Tushar , Guan Cuntai
Published: July 2020

Stroke is one of the leading causes of long-term disability among adults and contributes to major socio-economic burden globally. Stroke frequently results in multifaceted impairments including motor, cognitive and emotion deficits. In recent years, brain–computer interface (BCI)-based therapy has shown promising results for post-stroke motor rehabilitation. In spite of the success received by BCI-based interventions in the motor domain, non-motor impairments are yet to receive similar attention in research and clinical settings. Some preliminary encouraging results in post-stroke cognitive rehabilitation using BCI seem to suggest that it may also hold potential for treating non-motor deficits such as cognitive and emotion impairments. Moreover, past studies have shown an intricate relationship between motor, cognitive and emotion functions which might influence the overall post-stroke rehabilitation outcome. A number of studies highlight the inability of current treatment protocols to account for the implicit interplay between motor, cognitive and emotion functions. This indicates the necessity to explore an all-inclusive treatment plan targeting the synergistic influence of these standalone interventions. This approach may lead to better overall recovery than treating the individual deficits in isolation. In this paper, we review the recent advances in BCI-based post-stroke motor rehabilitation and highlight the potential for the use of BCI systems beyond the motor domain, in particular, in improving cognition and emotion of stroke patients. Building on the current results and findings of studies in individual domains, we next discuss the possibility of a holistic BCI system for motor, cognitive and affect rehabilitation which may synergistically promote restorative neuroplasticity. Such a system would provide an all-encompassing rehabilitation platform, leading to overarching clinical outcomes and transfer of these outcomes to a better quality of living. This is one of the first works to analyse the possibility of targeting cross-domain influence of post-stroke functional recovery enabled by BCI-based rehabilitation.
Zirconium-based metallic glass and zirconia coatings to inhibit bone formation on titanium
Authors: Rajan S Thanka , V V Anusha Thampi , Terada-Nakaishi Michiko , Chen Peng , Hanawa Takao , Nandakumar A K , Subramanian B
Published: July 2020

Surface-modified commercially pure titanium (Cp-Ti) with zirconium (Zr)-based thin film metallic glasses (Zr-TFMGs) and ZrO2 thin films were surgically implanted into the tibiae of rats; the bone formation was analyzed to examine the performance of the coatings as a biomaterial. Zr-TFMGs and ZrO2 thin films were coated on Cp-Ti substrates to monitor the control of assimilation in vitro and in vivo. The microstructural and elemental analyses were carried out for the as deposited thin films by x-ray diffraction (XRD), transmission electron microscopy and x-ray photoelectron spectroscopy. TFMG- and ZrO2-coated Ti specimens were immersed in simulated body fluid (SBF) for a period of 21 days to evaluate the calcium phosphate precipitation in vitro. XRD, x-ray photoelectron spectroscopy and scanning electron microscopy/energy dispersive x-ray spectroscopy were used to quantify the mineralization on the coated Zr-TFMG and ZrO2. In vitro corrosion studies showed that the Zr-based TFMG and ZrO2 coatings sustained in the SBF, exhibited superior corrosion resistance to the bare crystalline Ti substrate. Wettability studies showed TFMG and ZrO2 coatings with a hydrophobic nature, and the TFMG-coated SBF-submerged specimens showed a hydrophilic nature. The in vitro cell viability of MC3T3-E1 cells showed good cell proliferation and low cytotoxicity. The calcification deposits were evaluated by staining with alizarin red S, which showed a lower calcium formation on Zr-TFMG compared to ZrO2. The present work also aims to assess the assimilation behavior of Cp-Ti, Zr-TFMG and ZrO2
in vivo by inserting the coated specimen in the femur of rats. After post-implantation of 8 weeks, specimens were examined by micro-CT evaluation. The bone contact ratios as calculated were 72.75%, 15.32% and 38.79%. Consequently, the bone affinity was Cp-Ti wire >ZrO2-coated Ti wire >Zr48Cu36Ag8Al8-coated Ti wire.
Stress–strain analysis of rock mass during mining of protective pillar of vertical shaft
Authors: Neverov SA , Shaposhnik Yu N , Nikolsky AM
Published: July 2020

The implemented studies aim at the geomechanical assessment of safe mining, including safety pillars, within the limits of the protective pillar of shaft RESH in the Irtysh Mine, with estimation of influence exerted by stresses and strains on the rock mass, permanent excavations and ground surface. Slacked replenishment of the raw material resources makes re-extraction of ore reserves from pillars highly topical. It is found that ore loss in mining of the protective pillars reach 30% and above of total reserves at some deposits. Based on the analytical solutions and 3D FEM modeling in terms of the Irtysh Mine, the authors validate feasibility of safe partial extraction of ore reserves from the protective pillar of shaft RESH without aggravating effect on the shaft operation and on the ground surface. The feature of this study is using both specification documents and mathematical modeling, with regard to geology, structure and lithology of a deposit and rock mass, physical and mechanical properties and geometrical complexity of mine objects, which essentially improves studies into stability of underground openings and ground surface. It is found that the basic measure of safety I mining of the protective pillar of shaft RESH is establishing safety pillars.
Risk reduction in underground mining of coal-bearing coal seams with hydraulic fracturing
Authors: Serdyukov SV , Shilova TV , Rybalkin LA
Published: July 2020

The paper discusses influence exerted by the parameters of hydraulic fracturing on flow coefficient in parallel holes in pre-mining degasification of coal seam non-unloaded from rock pressure. The rates of coal degasification without hydraulic fracturing, as well as with nondirectional and multistage hydraulic fracturing are compared. Effect of different-type fracks on risk reduction in underground coal mining is assessed. The obtained results allow estimating efficiency of the hydraulic fracturing modifications currently in use in coal mines.
Extraction of ore reserves from pillars in room-and-pillar mining
Authors: Shchukin SA
Published: July 2020

The geotechnical situation in mines using the open stoping methods is governed by complex geomechanical behavior of rock mass around rib and level pillars. The impact of rock pressure on underground excavations grows in this case, and dynamic events due rock pressure happen more often. The latter became the reason for implementing this research. In terms of steeply dipping ore bodies, safe mining of earlier left pillars is feasible. The best scenario for pillar extraction, considering their parameters, is caving to open and partly filled with overlying rocks stopes. The geomechanical calculations during justification of mining parameters during extraction of ore reserves from pillars have determined regular patterns in the stress–strain behavior of rocks mass, which contributes to qualitative and quantitative prediction of safe and feasible mining conditions. The zones of instability in structural elements of the geotechnology, including pillars, are detected. The author proposes the order and sequence of pillar caving to open and partly filled stopes at the admissible completeness and quality of extraction.
Thermo-fluid analyses for UCN cryogenic system
Authors: Okamura Takahiro , Kawasaki Shinsuke
Published: July 2020

The TUCAN collaboration is now developing the new cryogenic system for ultra-cold neutrons experiments (UCN). This cryogenic system requires superfluid helium (He II) around 0.8 K to 1.15 K because cold neutrons are down-scattered by isopure He II with such temperature range to become UCN. Dynamic heat load applied to He II during UCN production will be as high as approximately 10 W. In order to satisfy such requirements, not only 4He but also 3He has to be circulated through the cryogenic system. There are sixteen heat exchangers for 4He and 3He. In order to design these heat exchangers properly, thermo-fluid simulations are carried out. Some simulations of them are nontrivial because they include film boiling phenomena in superfluid, molecular gas dynamics effect, transition from single phase flow to two phase flow and discrimination of such kinds of the complicated flow behavior. In addition, Time dependent thermo-fluid behaviors of He-II are also simulated using two fluid model and superfluid turbulent model to clarify the He II behavior. In this presentation, the simulation schemes and some results will be discussed.
The Mechanical Performance of Pipe Based on Fiberglass Reinforced with Plastic Waste (FRPW) Composites
Authors: Marsi Noraini , Subramaniam Lingeshavaran , Rus Anika Zafiah Mohd , Sulong Nurulsaidatulsyida , Fodzi Muhammad Haikal Mohd , Huzaisham Nur Athirah , Yusuf Nik Alnur Auli Nik , Mahmood Salwa , Shaari Muhammad Farid , Shariff Hafizuddin Hakim
Published: July 2020

The project research present the mechanical performance of pipe based on fiberglass reinforced with plastic waste (FRPW) in plant application system. The use of FRPW able to reduce corrosion problem faced by oil and gas industry. In this study involved four types of combination ratio of fiberglass reinforced with plastic waste (FRPW) of 1.0: 0.5; 1.0:1.0; 1.0:1.5; and 1.0:2.0. The fabrication process started with grinding process of plastic waste into small size in the range of 0.1 mm. Fiberglass then reinforced with plastic waste by mixed with resin and hardener with ratio of 2: 1 and poured into the cylinder mould. There is a possibility fiberglass from 10-40% by weight result in substantial increase in elastic modulus, accompanied by an increase in strength with reduced ductility 1.0 of ratio. The tensile test showed clearly exhibited that 1.0 of plastic waste reinforced fiberglass with stand the higher maximum force value of 2.69 kN. For the bending test ratio of 1.0 of plastic waste withstand the higher bending strength at 5.29 kN. Ratio of 1.0 FRPW is more suitable for produced pipe in plant application system due to matrix-reinforcement bonding for each pipe sample after conducting tensile strength. The result obtained that ratio 1.0 of FRPW shown good matrix-reinforcement bonding.
Black Liquor Pretreatment of Concorb and Enzymatic Hydrolysis for Lignocellulosic Bioethanol
Authors: muryanto Muryanto , Handayani Eka Mardika , Irawan Yan
Published: July 2020

Lignocellulosic bioethanol from corncob could be a promising alternative fuel because of abundant resources, and it will not interfere with the food supply. Pretreatment is the first step in a lignocellulosic bioethanol process. One of the effective pretreatments is alkaline pretreatment because it gives the cellulose-rich material for enzymatic hydrolysis. However, it produces black liquor as wastewater that provides environmental impacts. The black liquor from Empty Fruit Bunch (EFB) pretreatment was collected and used for pretreatment of corncob to reduce wastewater from bioethanol production. The pretreatment process was conducted in a 5-liter reactor. The pretreated corncob was hydrolysis with cellulase enzyme and converted to ethanol by Saccharomyces cerevisiae. The delignification of corncob using EFB-black liquor was 45.82%. The black liquor pretreatment was increasing ethanol production 3.25 times than untreated substrat after saccharification and fermentation process by Saccharomyces cerevisiae (36.39 g/l).
Characterization of Fresh Sidoarjo Mud as Material on Geopolymer System
Authors: Syarwan  , Putri Kiki Yolanda , Ruhana  , Miswar  , Fauzi Amir
Published: July 2020

Sidoarjo mud is the alternative cementitious material which derived from a volcano mud eruption in Porong, Sidoarjo, East Java, Indonesia. The calcination of fresh sidoarjo mud in high temperature was known rich in the content of Si and Al that has similar chemical content with the material of OPC. However, the calcination process had caused the consumption of energy, time duration and cost in the production. To solve the problem, this study was required to investigate the fresh sidoarjo mud without the calcination process. However, material of FSM was analyzed to understand its feasibility as a material in geopolymer referring to the material of fly ash. The results showed that the material of FA consisted of quartz (SiO2), mullite (3Al2O3 2SiO2 or 2Al2O3 SiO2) and hematite. While, the material of FSM consisted of quartz (SiO2), mullite (3Al2O3 2SiO2 or 2Al2O3 SiO2), magnetite (Fe3O4), hematite (Fe2O3), and rutile (TiO2). The particle of FA was amorphous and sphere with the misty surface that caused the absorption of alkaline solution and reduced the workability on fresh geopolymer mortar. While the particle of FSM was the agglomerate irregular shape with the rough surface that also caused the absorption of alkaline solution and reduced the workability on fresh geopolymer mortar. The analysis of FTIR identified that the material FA and FSM had the stretching in the gel of Si-O-Al and Si-O-Si. The compressive strength reached optimum at the replacement of 5% FSM.
Effect of POFA as a replacement material on fly ash based geopolymer mortar
Authors: Mulizar  , Fazliah  , Iskandar  , Aiyub  , Fauzi Amir
Published: July 2020

Ordinary Portland Cement (OPC) is widely used as the material for the construction. The production of OPC has caused an issue on the environment, due to the release of CO2 in the air. The use of by-product or waste material from the industry as an alternative material in the concrete was considered to be a solution to cover this issue. Geopolymer was the advance method that was able to use by-product or waste material to replace OPC as the binder in the construction. However, this material should be rich in content of Si and Al, it was due to the reaction of waste material with the alkaline solution formed the gel of Si-O-Si and Si-O-Al that contributed to the mechanical properties especially compressive strength. Palm oil fuel ash (POFA) is a waste material from the furnace of oil palm that is also rich in the content of Si and Al so that it was considered a new material in geopolymer binder. The method to general geopolymer binder referred to the conventional method. The results showed that the analysis of XRD described the material of POFA in the crystalline with mullite, magnetite, hematite, and rutile. The analysis of FTIR identified that the material POFA has the stretching in the gel of Si-O-Al. The analysis of SEM showed that the particle of POFA has a rough surface that reduced the workability and longer setting time compared to the mixture of FA based geopolymer. Furthermore, the maximum compressive strength is 23 Mpa with the replacement of 5% POFA.
Aged Reduction Prediction of the Road Plan Due to Overload On the Pancer Road, Pesanggaran District, Banyuwangi
Authors: Wari WN , Suryani E , Ulfiyati Y , Syafa’at IW
Published: July 2020

Jalan Pancer is grade 3 roads with the heaviest axle loads of 8 tons, the age of the road plan is 5 years. But Jalan Pancer has been passed by heavy vehicles with the heaviest axle loads of more than 8 tons which caused premature damage to the road. Therefore this study aims to determine the predicted reduction in the life of the road plan caused by overloading from the vehicles. The research method used is to conduct a traffic survey to get Average Daily Traffic value and identify the heavy vehicles. The data obtained were analyzed to obtain the value of Vehicle Damage Factor (VDF) for each type of vehicle and the value of Cummulative Equivalent Standard Axle-CESA for the life of the road plan. The comparison results among VDF value of the survey and VDF value of the plan conclude that road damage factor greate. Because of the overload conditions the age of the plan is only 1 year 9.7 months, there is a decrease in the life of the road by 3 years 2.3 months in the second year, so it can be concluded that Jalan Pancer suffered early damage before the planned age (5 years).
Synthesis and Characterization of Microfiltration Ceramic Membrane Based on Fly Ash and Clay Mixture Using Sintering Method
Authors: Diana S , Fauzan R , Arahman N , Razi F , Elfiana E
Published: July 2020

Ceramic membranes made from low-cost materials have increasingly been developed. Fly ash is a waste from cement industries, while clay is a natural resource that can be easily found to be used as economical mixed materials in the production of ceramic membrane. The manufacture of microfiltration ceramic membrane from fly ash - clay mixture has been carried out using the sintering method for 4 hours at low sintering temperatures variations at 750 °C (M1), 800 °C (M2), 850 °C (M3) and 900 °C (M4), respectively. The results showed that the ceramic membrane that was sintered at a temperature of 900 °C (M4) had the optimum characteristics with a porosity of 40.82%, a density of 1.0026 gr/cm3. From scanning elctron microscopy (SEM) analysis showed that the M4 membrane was classified as a microfiltration membrane with an average pore size of 0.64 μm. The energy diepersive x-ray (EDX) analysis showed that the composition of the M4 membrane was dominated by elements O, Si, and Al. Moreover, the x-ray diffraction (XRD) analysis showed that the fraction patterns of the membranes (M1, M2, M3, M4) were dominated by the quartz phase (SiO2) and illite phase ((KH3O)Al2Si3AlO10(OH)2).
Increased Absorption Capacity Of Organokaolin Adsorbents In Absorb Metals Using Microwave Technology
Authors: Syafruddin  , Putra Alfian , Ramadhana Suci , Pardi
Published: July 2020

This study about the absorption of iron and magnesium as metal ions in water solutions and kaolin were used as adsorbents. The power of Kaolin as adsorbent still very low so it is necessary to modify kaolin using acyl sulfonate (ABS) surfactant which is an organic compound. The aim is to increase the absorption capacity of kaolin in absorbing metal ions contained in water using modified kaolin to get effective absorption results in absorbing metal ions, especially iron, this research was carried out by varying microwave irradiation time 5, 15, 30, 50 and 80 minutes using surfactant kaolin modification and without surfactant modification, the waste used was artificial waste with an initial concentration of 100 mg / l. The samples were analyzed using Atomic Absorption Spectrophotometers (AAS), while the characteristics used were Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). Kaolin modification with microwave use in the adsorption process results in a decrease in artificial Fe waste at 3 minutes irradiation time on modification of efficiency reduction of 72% and Mg waste at 30 minutes decreased by 61%.
The Shortest Path Finder for Tsunami Evacuation Strategy using Dijkstra Algorithm
Authors: Pratiwi A F , Riyanto S D , Listyaningrum R , Aji G M
Published: July 2020

Having a tsunami early warning system during the tsunami disaster is important. The tsunami early warning system that is widely applied in Indonesia using loudspeakers and information board as a medium to convey information directly to the community during the disaster. The information provided is only about the status of the disaster and what needs to be done. People who panic, tend to choose the evacuation route through the main roads without thinking that the path will become very crowded resulting in total congestion. This paper discusses a tsunami evacuation strategy by finding the shortest path of evacuation route using dijkstra algorithm. This system contains information about the shortest evacuation routes that can be taken by the community towards a safe location, either vertically or horizontally. So, people can evacuate vertically or horizontally based on the geographical location of their residence. This system will be implemented in Cilacap districts. Shortest evacuation route is determined using the djikstra algorithm. Disaster-prone locations is the starting vertex and safe locations is finish vertex.
Pollutant Absorber Design to Minimize Air Pollution Emissions from Industry
Authors: Ruhiat Yayat , Guntara Yudi
Published: July 2020

Pollutants emitted from industries vary depending on the type of fuel and the height of the chimney used. The higher the chimney used, the further the pollutant distance emitted. In this research, Pollutant Absorber was made with a condensation system using activated coconut shell charcoal. The research method uses Research & Development with the Design for Production (DFP) approach. In developing the model, pollutant emission analysis is carried out: before entering the chimney, during the chimney, and after exiting the chimney. Then, in designing tools to design absorbent devices, chimney designs with coconut shells are made as absorbent. In creating and making tools, it is done in two ways, namely simulation and testing. The results of the research are models of the distribution of air pollutants from industry, air pollutant absorbent designs emitted from industry, and prototype devices capable of absorbing SO2 of pollutants emitted through the chimney.
Identification the Jakarta Fault using MS-SVD (Multi Scale - Second Vertical Derivatives) Method Gravity Data
Authors: Yudyawati K N , Rosid M S
Published: July 2020

Jakarta is a metropolitan city in Indonesia with high population. Geologically, its location has the potential to be affected by earthquakes from subduction zones as well as from local faults such as the Cimandiri, Lembang, and Baribis faults. Earthquake history showed that in 1780 and 1834 Jakarta was affected by an earthquake with magnitude Mw 8, destroying existing infrastructure. Several geoscientists believed the source of the fault is located in the south of Jakarta. Study with primary gravity data using the MS-SVD supported by the MS-HDVD method is a good method for identifying faults. From looking at the zero value shift on the MS-SVD graph, a fault zone is visible in the south of Jakarta. It is also confirmed by the CBA map that has contrast gravity between south and north of Jakarta. The faults have parallel-normal and parallel reverse type in East-West direction with dip angle for more than 79°. According to the fault that has been identified, south of Jakarta is evidently crossed by the fault, so the city safety needs to be considered especially for the potential of upcoming natural disasters. However, 2D forward modeling shows that subsurface Jakarta does not have density contrast between rock layers significantly.
Fault Plane Estimation Through Hypocentres Distribution of the July-August 2018 Lombok Earthquakes Relocated by using Double Difference Method
Authors: Rosid M S , Widyarta R , Karima T , Wijaya S K , Rohadi S
Published: July 2020

Indonesia is actually located in collisions between three large plates of Eurasia, Indo-Australia, and Pacific. It causes earthquakes to occur frequently in several regions, one of which occurs sequentially the 5 big shocks in Lombok in period of July-August 2018. There is a Flores thrust fault in the North of the Lombok Island region. The objective of study is determining whether the earthquakes sequence is related to the fault. The study is done through the analysis of relocated 321 of 489 hypocentres of the earthquakes acquired from 13 BMKG stations in July-October 2018. The hypocentres are relocated by using the double-difference method. The events are focused only with magnitude > 3.5 M. The relocation result is validated by the RMS residual histograms with the average value close to 0. The results show that the seismic activity mostly spread in the northern part of the Island of Lombok. The distribution of the epicenter points tends to form a pattern oriented from West to East in the northern region of the island which is thought to be the zone of the faults. The events most likely have not generated and not laid along the Flores Fault.
Ultrasound Assisted the Degradation of Methylene Blue Using WO3-Deoiled Spent Bleaching Earth as a catalyst
Authors: Hindryawati Noor , Julia N.S R.R. Dirgarini , Panggabean Aman S. , Wilsoma
Published: July 2020

Spent Bleaching Earth (SBE) that has been impregnated with WO3 can degrade methylene blue through sonocatalytic. The stages of this research are SBE preparation, activation, WO3-SBE modification through wet impregnation process and sonocatalytic test. WO3-SBE is characterized using SEM and XRD. In the SEM results, there are cavities in the surface morphology of SBE after activation and after impregnation, the cavities are covered. WO3-SBE XRD diffraction pattern shows the presence of WO3 at an angle of 2θ = 28.855°; 34,813°. The percentage of degradation of methylene blue was 99.12%, using 0.15 grams catalyst, 100 ppm concentration and 15 minutes contact time.
Interaction of Enzyme-Substrate from Indigenous Cellulolytic Bacteria by Bioinformatics
Authors: Maryanty Yanty , adryati Tri , Suharjono  , Bambang Sumitro Sutiman
Published: July 2020

This study aims to predict the degradation mechanism of cellulose substrate in silico from the results of isolation and test the potential of cellulolytic bacteria from rice fields in Greater Malang in producing cellulolytic enzymes, among others: β-1, 4 exoglunase, β-1, 4 endoglucase and β - glucosidase, identified isolates that have high potential in producing cellulolytic enzymes based on 16S rDNA ie isolates A, B, D and F. Only Isolate B was successfully predicted by its substrate enzyme interaction both homologically and based on the results of the isolation of the cellulite gene. Homology B isolate analysis results showed that the hydrogen bonds that occur in glutamic acid GLU257, tryptophan 207, serine 264 and glutamic acid 169, while hydrophobic interactions occur in tryptophan 207 bonds. While the results of the analysis based on isolation of cellulase encoding genes from isolate B were predicted in-silico showed the interaction between hydrogen bonds in tyrosin (TRY 299), glutamine (GLU201 and GLU 342.72), Asparagine (ASN 200) and glycine (GLY 384). This interaction is slightly different from the insilico results obtained homologically i.e there is no interaction with serine and glutamate acid, but with asparagine. Isolate B predicted that its homology in silico can degrade cellulose substrate with the binding affinity of -7.0 Kcal/mol while based on the results of isolation of cellulase encoding genes shows the degradation ability of cellulose substrate with the binding affinity of -6.5 Kcal/mol.
Fibre-based Saturable Absorbers for Pulsed Generations in the 1-micron Region
Authors: Rahman M F A , Ahmad M T , Rusdi M F M , Latiff A A , Harun S W
Published: July 2020

In this paper, we demonstrated and compared several fibre-based saturable absorbers (SAs) used in the generation of stable Q-switched fibre lasers in the 1-micron region, using 1.5 m long Ytterbium-doped fibre (YDF) as the gain medium. The tested fibre SAs consist of four segments; (1) 8 cm long Hafnium bismuth erbium-doped fibre (HBEDF), (2) 12 cm long Ytterbium-doped fibre (YDF), (3) 20 cm long Titanium dioxide-doped fibre (TDDF) and (4) 11 cm long Thulium-doped fibre (TDF). The fibre segments were joint with a single-mode fibre (SMF28) of approximately 10 cm at both of their ends via fusion splicing to become useful fibre-based SAs. The Q-switched fibre lasers stably operated at ~1060 nm wavelength. Among these fibre SAs, the highest pulse energy (191 nJ) was achieved through the TDDF SA, while the shortest pulse width (1.97 ms) and the highest pulse frequency (74.2 kHz) were obtained via the YDF SA. These fibre SAs provide simple operation, high stability and high thermal damage threshold which are desirable for high power laser operations.
Methods of mathematical statistics application in assessing the density of actual and forecasting distribution density of residual oil reserves
Authors: Gabdrahmanova K F , Izmailova G R , Samigullina L Z
Published: July 2020

The authors propose a method for mathematical statistics application for residual reserves in deposits predicting. They propose a method for making residual the current reserves distribution model based on geological and physical characteristics of the reservoir analysis. The article takes the first step to justify the use of statistical methods in the conditions of operational facilities of the Romashkino and Tuymazy oil fields. One of the urgent problems associated with the effective oil fields development is not only a reliable estimate of the distribution density of residual reserves, but their forecast for the subsequent development as well. There are many ways to estimate residual reserves nowadays. All of them are, to one degree or another, based on residual oil saturation ratio estimating, which in the conditions of insufficient accuracy of geophysical methods, as well as their rise in price (carbon-oxygen logging, for example) or their limited application, calls for other approaches in the residual oil reserves value assessing, based, for example, on the field data. Logging methods have their limitations. Their application requires other approaches in residual reserves amount assessing. Having analyzed multiple studies results, such as, for example, field data, implemented in the SPSS program regression analysis, which allows statistical data the processing the authors propose the mathematical statistics methods application in assessing the density of the actual and forecasting the residual oil reserves’ distribution density. The mathematical modeling results for oil from a porous medium displacement process are presented for Romashkino and Tuymazy oil deposits.
Study of efficiency of methods for determining fatigue limits through the example of its determination for welded joints of marine stationary platforms
Authors: Starokon I V
Published: July 2020

Currently, the world is actively engaged in the extraction of oil, gas and other useful resources at offshore fields using offshore stationary platforms. Due to the fact that the platforms are operated for a long time, fatigue damage accumulates in them. This issue becomes especially important when assessing the residual life of welded joints of the offshore platform, the repair of which is carried out using various technologies. The resource of such compounds is determined on the basis of the fatigue diagram, the key value of which is the fatigue limit. A large number of theories have been developed to determine the fatigue limit. However, calculations based on these theories do not always give a correct estimate. Therefore, the purpose of this article is to study the effectiveness of various methods for determining endurance limits using welded joints of offshore stationary platforms as an example and to select a method that allows obtaining the most accurate value of fatigue limit.
Monitoring of technological processes and assessment of technical condition of pumping units
Authors: Galeev A S , Bikbulatova G I , Boltneva Y A , Sabanov S L
Published: July 2020

Remote monitoring of pumping equipment operation in real mode is being widely introduced at oil and gas industry enterprises. The controllers applied in this process enable preventing progressive destruction of equipment and emergency failures and implementing automatic control of machines’ operation. The actual data collected by these controllers is transferred to the company’s servers and makes it possible to effectively set and address various tasks on equipment maintenance. However, there is still insufficient number of applications to address the problems of pumping equipment operation. The presented paper is aimed at resource efficient operation of equipment by obtaining the information on both actual and predicted technical state of the equipment in real-time mode. The main performance characteristics of a pump deteriorate in the process of its operation, followed by an increase in specific power consumption for injection (with the reservoir properties unchanged). Economic losses due to pump’s wear and tear are determined by the price of electricity and the cost of overhauling. Implementation of the designed monitoring system will make it possible to automatically decide whether further operation of the pump is unprofitable and if it needs to be overhauled. Based on the analysis of the trend of monthly unit costs, the pumping unit will be timely removed for major overhaul when the trend reaches its minimum, which shall provide an average annual economic benefit up to 4,000,000 rubles per pumping unit.
Separation of analytical signal for atomic-emission microwave plasma measurements
Authors: Drokov V V , Vl Drokov V , Kazmirov A D , Sinitskaya A V , Ivanov N A , Hodunaev A Y
Published: July 2020

The analytical signal for atomic-emission microwave plasma (AEMP) spectral analysis method is studied. It is shown that the signal consists of two parts: background signal, proportional to content of the analytical element in a sample shaped by submicron particles and metalorganic compounds; pulse signal, proportional to content of analytical element in coarse discrete particles. The “dynamic discrimination” algorithm is suggested that allows measuring the element content in a liquid or powder ore sample independently of the content shape using AEMP method. It is shown that atomic absorption (AA) and AEMP measurements of Fe, Cu agree within error for samples both low and high in content of element in submicron particles.
Elimination of aperiodic components of measuring elements of relay protection
Authors: Buryanina N S , Korolyuk Y F , Koryakina M L , Lesnykh E V , Suslov K V
Published: July 2020

The authors propose the algorithms to calculate the actual values of currents and their derivatives. The algorithms allow a sharp reduction in the aperiodic components of currents in the calculated actual values and their derivatives. The algorithms are developed to calculate the instantaneous values of positive- and negative-sequence currents when the information obtained during a time interval equal to two milliseconds or less is used. An algorithm is devised to calculate the sinusoidal components of the currents in the presence of aperiodic components in the samples. To eliminate the disoperation of digital relay protection and improve the accuracy of fault location, it is necessary to eliminate the influence of aperiodic components in the currents drawn to the measuring devices of relay protection. The algorithm completely eliminates the aperiodic component at any time constants and is implemented by four samples of currents. The four samples of currents separated by three sampling intervals are sufficient for calculating all the parameters of currents, including the positive and negative-sequence currents, in particular in the case when the magnetic cores of current transformers reach saturation. The proposed methods for setting the industrial frequency parameters to avoid the aperiodic components in short-circuit currents are based on the algorithms that process the data from three and four samples of currents.