bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanical properties of self-compacting concrete incorporated with high volume fly ash
Authors: Solikin M , Mulyanto T 
Published: May 2020

Abstract
Self-compacting concrete (SCC) is beneficial in concrete casting process as it does not need any tools for consolidation process. In addition, the utilization of High content fly ash in has proven in improving mechanical properties of concrete although the slow strength development is an issue to coop with. This paper presented an experimental program on the mechanical properties test of high strength self-compacting concrete incorporated with high content fly ash. The mix proportion for the concrete was prepared based on ACI high strength concrete with the design strength of 45 MPa. The mechanical properties test consists of slump flow test, compressive strength test development, flexural strength test and water absorption test of concrete. The slump flow test was tested for fresh concrete and the strength development test was tested at the age of 14, 28 and 56 days. In addition, test for flexural strength specimen and absorption specimens were tested at the curing age of 56 days. Moreover, the high strength normal concrete specimen was prepared as control mix design. The result shows, less water was need to reach design flowability for Self-Compacting Concrete High content fly ash concrete and it gives impact to lower water absorption for the type of concrete. In addition, at the curing age of 56 days the compressive strength of high strength high content fly ash-self compacting concrete was comparable to the normal concrete.
Identification parameter system for mathematical modeling BLDC motor using transfer function models
Authors: Anshory I , Robandi I , Wirawan  
Published: May 2020

Abstract
The parameter system identification of Brushless Direct Current (BLDC) motorbike on electric bicycles is one of the important factors that support success in improving a stable and reliable control system. The purpose of this paper is to explain the mathematical modeling of BLDC motors by system identification parameters. The method of system identification parameters used in this study is experimentation, namely the pulse width modulation (PWM) signal generation process and the collection of input data in the form of current, voltage, and output data such as speed is carried out using sensors connected to the microcontroller. The input and output data are then simulated using the transfer function model found in the system identification toolbox in the MATLAB program. From the results of testing and simulations carried out on the BLDC motor system, a mathematical model was obtained in the form of a transfer function with third-order transfer function is the best fit value than the others. The sequential values of the transfer function 1, 2 and 3 are 69.81, -1945, and 83.34.
Simulation of air flow loss in triangle pipe construction
Authors: Lubis S , Siregar C A , Abdilah F 
Published: May 2020

Abstract
The purposes of this research are to find out how the simulation of flow velocity, mass flow rate and pressure that occur in each variation of Reynold numbers on the triangle pipe arrangement of solid work software. By using test and simulation analysis methods, using a number of tools and materials so that they can be simulated and simultaneously analyze the resulting design. The tools and materials used in the simulation and analysis process in this design are (1) computers with specifications of the Intel (R) Xeon (R) CPU E3-1246 v3 @ 3.50Ghz 3.50 GHz (2) a solid work keel device for analyzing pressure. This fluid mass flow rate is influenced by the velocity of fluid flow and the temperature at this fluid can influence fluid density and specific gravity. This fluid speed can affect the pressure that hits the pipe. In the simulation results, there is a significant pressure change due to the speed that changes over the sidelines of the same pipeline. This change raises the loss of friction in the arrangement of the pipe pipeline due to the pressure factor that hit the pipe. The pressure that occurs is influenced by the velocity of fluid flow, fluid mass flow rate and cross-sectional area on the triangle pipe arrangement.
Engineering of motorcycle exhaust gases to reduce air pollution
Authors: Siregar A M , Siregar C A , Yani M 
Published: May 2020

Abstract
Air pollution from motor vehicle exhaust emissions is increasing, so it is necessary to attempt to control its exhaust emissions. Given the dangers of exhaust emissions, efforts need to be made to control and reduce air pollution so that negative impacts on people and the environment can be reduced. One engineering technology as a manifestation of vehicle emission control is engineering and modification of the exhaust gas channel. Engineering and modification are expected to be able to make a tool that will be able and function to reduce the danger of exhaust gases. The researcher will conduct experiments and manufacture of tools and initial testing on one motorized vehicle to see and observe the composition of the exhaust gas produced from the exhaust. The elements to be observed are CO values, HC values, and CO2 values as comparative data. The tool that will be used to observe and see these elements is the Gas Analyzer tool. This tool is one instrument that is useful for measuring the portion and composition of a combined gas. From the results of testing and analysis obtained data on the exhaust emission test with an average engine speed of 500 rpm, and with the temperature of the exhaust tube 40 °C to 45 °C. After testing the standard exhaust model, then testing the engineering exhaust model which added 50 gr, 70 gr, and 90 gr scrap of stainless steel obtained the best conclusion to reduce and reduce the danger of exhaust emissions is engineered exhaust which added 70 g scrap of stainless steel and when compared to a standard exhaust, CO elements dropped to 71.09% and HC elements dropped to 48.26% and CO2 elements dropped to 66.35%.
Multiscale Modelling and Analysis on the Heavy-duty Hydrostatic Journal Bearing for a Precision Press Machine
Authors: Shang Youyun , Cheng Kai , Ding Hui , Chen Shijin 
Published: May 2020

Abstract
The present study aims to predict the performance of hydrostatic journal bearings during steady-state operation through multiscale modelling and analysis. An innovative multiscale modelling approach is presented for numerical modelling and analysis of the hydrostatic journal bearing as configured and designed, particularly for the precision press machine. With the challenging environment for journal bearings under hydrostatic pressures and surface features, elastic modulus of oil and viscosity-temperature characteristics are often neglected while against heavy-loading and precision engineering requirement. This research takes into account of oil elastic modulus and viscosity-temperature characteristics to investigate the intrinsic relationship between the pressures within the hydrostatic bearing and its surface texture, feature size and locations being considered. This paper concludes with a further discussion on the potential and application of the approach in precision engineering.
Park Accessibility Analysis Based on Location Information and GIS: Take Shanghai Hongkou District As An Example
Authors: Zhang Ziran , Fan Shengxi , Zhang Huayan 
Published: May 2020

Abstract
Spatial accessibility is one of the methods to study the rationality of park design. This paper is taking Hongkou District Park in Shanghai as an example, by using the ARCGis application as analysis tool to analyze that the relation between the location of Park entrance and location of the community, and to calculate the different time cost of people who is under the walking and cycling mode to put forward the distribution of park entrance location which is based on the accessibility of riding and walking.
Temperature Variation of Wet Clutches in the DSG Vehicle during a 10km Driving Cycle
Authors: Liu Jikai , Chen Jie 
Published: May 2020

Abstract
The temperature of wet clutches has a vital influence on the vehicle in terms of dynamic performance, service life, wear characteristics, etc. To investigate the temperature variations during the operation process, a detailed dynamic powertrain model of the DSG vehicle is established firstly to calculate the dynamic load of different clutches. Then, a thermal resistance model for the gearbox cooling system is built to predict the temperature of wet clutches. Integrating the dynamic model and the heat transfer model, a co-simulation model is finally obtained. The simulation results illustrate that the temperature of the clutch used for the launching process has a sharp increase from 100 °C to 123 °C; however, within a 10km driving cycle, the temperature of five clutches are all lower than 125 C, which meet the requirements of the vehicle.
Mechanical Properties Improvement of Clays Using Silica Sand Waste and Dust Sand Foundry Waste
Authors: Gunarti Anita Setyowati Srie , Raharja Irwan 
Published: May 2020

Abstract
The increase of industrial waste and many road damages due to unstable subgrade invite the research on soil additives made from waste treatment as stabilizers to improve the mechanical value of clay. This study used California Bearing Ratio Test based on the ASTM standard for mechanical properties testing of clay. The soil stabilization method was carried out by mixing the clay with Silica Sand waste and Dust Sand Foundry waste in a predetermined composition. California Bearing Ratio value of 2.5 mm penetration showed a significant increase of 47.9% from the original clay in the composition of the waste 5% Silica Sand and 5% Dust Sand Foundry.
Micro/nanostructured MTMOs as Electrocatalysts for Oxygen Evolution Reaction in Alkaline Medium
Authors: Flores Charles Lois , Balela Mary Donnabelle 
Published: May 2020

Abstract
Different nanostructured mixed transition-metal oxides were synthesized using a facile and controllable hydrothermal method. Incorporation of Cu2+ and Ni2+ in Co3O4 structure led to an interesting morphological transformation, from quasi-spherical nanoparticles to microspherical urchin-like aggregates of radially assembled nanoneedles. These oxides have notable low crystallite size, narrow size distribution, and high degree of crystallinity. In general, partial cobalt substitution resulted in an improved electrocatalytic activity for oxygen evolution reaction (OER), with NiCo2O4 demonstrating superior performance among the catalysts prepared. It recorded a low overpotential of 374 mV and achieved high stability, making it competitive with state-of-the-art RuO2 and IrO2 (387 mV). This material is of great potential for sustainable energy applications.
The Effect of Micro-Eggshells and Aluminium Hydroxide on Tracking Resistance of Silicone Rubber Composite
Authors: Khaigunha Pattarabordee , Wongwuttanasatian Tanakorn , Suksri Amnart 
Published: May 2020

Abstract
Break down due to surface tracking is one of the critical insulation failures, especially in the polymeric insulation. It has made worse the reliability of the power transmission system. This present work attempts to solve the problem by observing the effect on tracking resistance of adding micro-eggshells and aluminum hydroxide into the silicone rubber. In order to fabricate the composite specimen, red eggshells (63 to 74 μm), aluminum hydroxide, and RTV silicone rubber were procured. The constant voltage test method, according to the IEC-60587 standard, was used to evaluate the tracking resistance; each specimen was applied by 4.5 kV for 1 hour, and the tracking length was declared as the inverse of tracking resistance. Besides, the rule of mixtures was employed to estimate the thermal conductivity. The results show that the tracking resistance of the composite specimens was overall higher as compare to the pure rubber. Moreover, It was found that tracking resistance and thermal conductivity decreased when the eggshells increased. It was described that the rise of thermal accumulation on the insulator surface in the hybrid composite caused by lower thermal conductivity. Therefore, it could be concluded that the mixing of micro-eggshells and aluminum hydroxide should not be used as fillers for suppressing the tracking failures.
Automatic Digital Fringe Projection for Advanced Micro-Scale Connector Manufacturing System
Authors: Lu Ching-Hua , Liu Cheng-Yang 
Published: May 2020

Abstract
The digital fringe projection microscope has been investigated and used to estimate three-dimensional shape of micro-scale connector for advanced manufacturing system. This measurement system consists of digital projector, optical lenses, stereo microscope, and digital camera. In the software, the imaging program based on including black and white structure light, seven-step phase-shifting calculation, and path-independent phase unwrapping is well developed. The imaging results indicate that the three-dimensional shape of micro-scale connector is acquired by using this measurement system. The optical resolution of this measurement system is 3 μm and the measurement speed is 0.6 s. This measurement system has excellent performance including easy operation, fast measurement speed and high resolution. This measurement system can be applied to real-time three-dimensional shape detection in product processing of micro-scale connector.
Application Phases for Productivity Improvement through Lean Methods Assessments in an Aeronautical Company – Case Study
Authors: Silvério Leandro , Trabasso Luís Gonzaga , Pessôa Marcus Vinicius Pereira 
Published: May 2020

AbstractA well defined manufacturing company focuses on lean practices along the whole product development process, not exclusively during the manufacturing and production phases. This study focuses on the application steps to be adopted for productivity improvement trough lean methods assessments in a product development company for the aeronautical industry. It also aims to provide insights for decision makers along the whole lean transformation patch, and to reduce the waste generation by eliminating the non–value–added activities resulted by a bad execution of the lean implementation tools and methods. By deploying the proposed study, the assessed enterprise increased its overall lean engagement level and production outputs.
On the optical nonlinearity in the GeSbSe chalcogenide glasses
Authors: Nedelcu Nicoleta , Chiroiu Veturia , Munteanu Ligia , Girip Iulian 
Published: May 2020

Abstract
Chalcogenide glasses GexSb40−xSe60 with composition 12, 25 and 30 at.%, synthesized from elements with 5N purity (Ge, Sb, Se) by the conventional melt-quenching method were studied. The spectrophotometer’s measurements were recorded to determine the optical properties. Models based on the absorbance and absorption coefficient are used to determine the optical band-gap energy. The Urbach energy is deduced in the

Ge

x

Sb

40
−
x

Se

60

thin film alloys with composition x = 12, 25 and 30 at.%. The electronic and structural properties are studied, and the influence of the Urbach energy in estimating of the nonlinearity in the optical properties of these glasses is discussed. The analysis is performed with respect to the Urbach parameter that quantifies the degree of crystallinity of the structure which can be used to understand the behavior of different diffractive, wave-transmission and fiber structures.
Trends of epitaxial perovskite oxide films catalyzing the oxygen evolution reaction in alkaline media
Authors: Antipin Denis , Risch Marcel 
Published: May 2020

Abstract
The oxygen evolution reaction (OER) is considered a key reaction for electrochemical energy conversion but slow kinetics hamper application in electrolyzers, metal-air batteries and other applications that rely on sustainable protons from water oxidation. In this review, the prospect of epitaxial perovskite oxides for the OER at room temperature in alkaline media is reviewed with respect to fundamental insight into systematic trends of the activity. First, we thoroughly define the perovskite structure and its parameter space. Then, the synthesis methods used to make electrocatalytic epitaxial perovskite oxide are surveyed, and we classify the different kinds of electrodes that can be assembled for electrocatalytic investigations. We discuss the semiconductor physics of epitaxial perovskite electrodes and their consequences for the interpretation of catalytic results. Prototypical mechanisms of the OER are introduced and comparatively discussed. OER investigations on epitaxial perovskite oxides are comprehensively surveyed and selected trends are graphically highlighted. The review concludes with a short perspective on opportunities for future electrocatalytic research on epitaxial perovskite oxide systems.
No-boarding buses: agents allowed to cooperate or defect
Authors: Saw Vee-Liem , Yue Chew Lock 
Published: May 2020

Abstract
We study a bus system with a no-boarding policy, where a ‘slow’ bus may disallow passengers from boarding if it meets some criteria. When the no-boarding policy is activated, people waiting to board at the bus stop are given the choices of cooperating or defecting. The people’s heterogeneous behaviours are modelled by inductive reasoning and bounded rationality, inspired by the El Farol problem and the minority game. In defecting the no-boarding policy, instead of the minority group being the winning group, we investigate several scenarios where defectors win if the number of defectors does not exceed the maximum number of allowed defectors but lose otherwise. Contrary to the classical minority game which has N agents repeatedly playing amongst themselves, many real-world situations like boarding a bus involves only a subset of agents who ‘play each round’, with different subsets playing at different rounds. We find for such realistic situations, there is no phase transition with no herding behaviour when the usual control paramater 2
m
/N is small. The absence of the herding behaviour assures feasible and sustainable implementation of the no-boarding policy with allowance for defections, without leading to bus bunching.
Dynamical aspects of nanoparticle formation by wire explosion process
Authors: Ranjan P , Nguyen D H , Chen L , Cotton I , Suematsu H , Chakravarthy S R , Jayaganthan R , Sarathi R 
Published: May 2020

Abstract
Copper nanoparticles (NPs) were produced by wire explosion process (WEP) and it was noted that the amount of energy (E) deposited on the wire and the ambient pressure play a major role on the size of particles formed. Dynamic diffusion and condensation processes of NPs formation by WEP were modelled. Calculations of critical size of embryo, activation energy and nucleation rate of the formation of NPs in WEP were made considering classical homogeneous nucleation theory. Decrease in critical size of nuclei and activation energy, increase in nucleation rate with high E (540 J) and low operating pressure (10 kPa) confirm the formation of small size NPs (26 nm). Different cooling rates due to unsymmetrical shape of the vapour cloud has been identified as the cause for generating mixed particle sizes. The qualitative analysis conducted in this work validates the obtained experimental results and can be used as a design tool for industrial apparatus to produce NPs in bulk.
Numerical simulation on the effect of sample geometry size on the metal flow behaviour during the forging process
Authors: Obiko J , Mwema F 
Published: May 2020

Abstract
This paper reports on the effect of sample geometry size on the metal flow behaviour using DeformTM 3D finite element simulation software. The simulation process was done at forging temperature of 1100 °C and upper die speed of 50 mm/second. The friction coefficient between the die and the sample interface was taken to be constant during the simulation process. The results of the effective stress and strain distribution in the deformed sample were reported. The results show that the effective stress and strain distribution in the deformed sample was non-uniformly distributed. The maximum effective strain occurred at the centre of the deformed sample for all the samples tested. The maximum effective stress occurred at the die-sample contact surface. At the contact surfaces, the effective stress decreased with a decrease in the sample size. The effective stress at the centre of the deformed sample increased with a decrease in the sample geometry size.
Unveiling the mystery: assessing the evolutionary trajectory of the Apaporis caiman population (Caiman crocodilus apaporiensis, Medem 1955) via mitochondrial molecular makers
Authors: Balaguera-Reina Sergio A , Vargas-Ramírez Mario , Ordóñez-Garza Nicté , Hernández-González Felipe , Densmore Llewellyn D 
Published: May 2020

AbstractThe Apaporis caiman (Caiman crocodilus apaporiensis) has been of particular interest due to its highly differentiated morphology. However, no molecular research has been done to clarify its taxonomy. We characterized the genetic variation within C. crocodilus by assessing the evolutionary trajectory of Apaporis caiman populations using mitochondrial molecular markers. We collected ten Apaporis caiman samples from the middle basin of the Apaporis River, Colombia, sequenced two mitochondrial genes [cytochrome oxidase I (COI) and cytochrome B (CytB)], and analysed them together with all available sequences from homologous gene fragments at GenBank for the species. Phylogenetic reconstructions revealed three main clades clearly differentiated across the C. crocodilus complex. These clades matched genetically and geographically with three of the four subspecies currently recognized (C. c. chiapasius, C. c. fuscus and C. c. crocodilus). However, we found low to almost non-existent genetic differentiation between C. c. crocodilus and the until-now morphologically recognized C. c. apaporiensis, suggesting that the latter is part of the genetic spectrum present within C. c. crocodilus. We reject the hypothesis of an expected elevated level of genetic variation due to isolation (supported by morphological differentiation) and support the idea of Apaporis caiman populations as a C. crocodilus ecomorph.
Development of multipurpose technologies products for pregnancy and STI prevention: update on polyphenylene carboxymethylene MPT gel development†
Authors: Weitzel Mary , North Barbara Best , Waller Donald 
Published: May 2020

Abstract
Current modern contraceptives rely heavily on the use of hormones. These birth control drug products, including pills, patches, injections, and IUDS, have been extremely beneficial to millions of women and their families over the past 50 years. But a surprisingly high number of women abandon such modern methods, many because they cannot tolerate the side effects and others because they have medical issues for which hormonal methods are contraindicated. In addition, modern hormonal methods are simply not available to many women. The extent of this problem is steadily becoming more apparent.
We present the case for developing simple nonhormonal vaginal products that women can use when needed, ideal products that are multipurpose and offer both contraception and sexually transmitted disease protection. Gel-based vaginal products are particularly well suited for this purpose. Gels are easy to use, highly acceptable to many women, and can be safely formulated to enhance natural vaginal defenses against infection. However, the development of a new chemical entity for this application faces significant technical and regulatory hurdles. These challenges and our solutions are described for polyphenylene carboxymethylene (PPCM), a novel topical drug in a vaginal gel nearing human clinical trials. We have advanced PPCM from benchtop to IND-enabling studies and provide a brief description of the complex development process. We also describe a simple lab assay which can be used as a biomarker for contraceptive activity to enable pharmacodynamic studies in vaginal contraceptive development, both preclinically and in early human clinical trials.