bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diffraction of Wigner functions
Authors: Creagh Stephen C , Sieber Martin , Gradoni Gabriele , Tanner Gregor 
Published: November 2020

Abstract
We describe the contribution of diffractive orbits to semiclassical approximations of Wigner function propagators. These contributions are based on diffractively scattered rays used in the geometrical theory of diffraction (GTD). They provide an extension of well-established approximations of Wigner-function propagators based on rays that propagate by specular reflection and refraction. The wider aim of this approach is to allow for diffractive mechanisms to be accounted for in Eulerian approaches to ray-tracing simulations. Such approaches propagate densities of rays rather than follow rays individually. They promise to be a more efficient means of performing ray-tracing simulations in complex environments with applications in, for example, planning of wireless signal coverage for mobile communication networks.
Synthesis and Size Control of Aluminum Nanoparticles using Solution Plasma Process
Authors: Liew B Y Y , Ranjit M S , Julaihi M R M , Yek P Y N , Shibayama T 
Published: November 2020

Abstract
This research was conducted to investigate the various control techniques to vary the size of aluminum nanoparticles through solution plasma process, specifically the submerged glow-discharge plasma process. Aluminum nanoparticles have received many attention due to their unique combustion, resistance and superhydrophobic properties. A lab-scale based submerged glow-discharge setup has been constructed to produce the nanoparticles. Different concentration of potassium carbonate electrolyte (0.1M – 0.5M) and cathode submerged length (50 mm – 100mm) were used in this study. The results were viewed and analyzed using scanning electron microscopy. As the major results showed that the diameter size distribution ranges from 80nm to 2µm. Higher concentrations have shown to produce smaller nanoparticles due to the overlapping of electron beams on the cathode surface. Also, shorter cathode submerged lengths have resulted in larger-sized nanoparticles.
Application of variable geometry turbine turbochargers to gasoline engines- A review
Authors: Dasgupta S , Sarmah P , Borthakur P P 
Published: November 2020

Abstract
An ideal engine today is considered to be one with low emission, low fuel consumption and high specific power output. Engine downsizing by turbocharging provides an answer toall the three. Though the traditional problems of poor low end torque and inadequate transient response have been overcome to a great extent using variable geometry turbine turbocharger in diesel engine, the application of variable geometry turbine turbocharger is in quite a nascent stage when it comes to gasoline engine. This article primarily describes all the important aspects of application of VGTs to gasoline engines right from when VGT’s were restricted to only very expensive research prototypes to the very recent application in cost sensitive production engines. Also at the same time,it highlights the need and development in the flow range of the turbocharger compressor, addressing problems of choke and surge in the turbo chargers compressor.
Direct Fermentation of Oil Palm (Elaeis guineensis) Trunk Sap to Bioethanol by Saccharomyces cerevisiae
Authors: Norhazimah A. H. , Siti F.M.N. , Aida M. , Dilaeleyana A.B. , Nur Shahirah M. A. 
Published: November 2020

Abstract
Oil palm agricultural biomass has a great potential for biofuel production due to its abundance and less pretreatment needed. In this study, bioethanol production from oil palm trunks sap was carried out by using yeast Saccharomyces cerevisiae. The suitability of the oil palm trunk sap for bioethanol production was tested by investigating the relationship between the oil palm trunk sap concentration and ethanol produced. The fermentation was conducted in static condition and without pH adjustment using 60, 80, and 100% oil palm trunk sap concentration. Results showed that the highest bioethanol production rate was achieved for 100% oil palm trunk sap (1.033 g/L.h), followed by 80% (0.744 g/L.h), and 60% (0.645 g/L.h). These results were influenced by the presence of sugars in the initial sap, suggesting that high substrate concentration does not inhibit bioethanol production. Therefore, the oil palm trunks sap showed significant potential as a renewable feedstock for the production of bioethanol without dilution.
Experimental Investigation of the Flexural Behavior of Steel Fiber Reinforced Concrete
Authors: Karzad A S , Al-Sadoon Z , Leblouba M , Maalej M 
Published: November 2020

Abstract
This research study is conducted to investigate the flexural behaviour of steel fiber reinforced concrete (SFRC) prisms incorporating different types and volume fractions of steel fibers, various grades of concrete, and different specimen depths, all tested under displacement control mode using four-point loading configuration. Two types of steel fibers (hooked end and straight) were incorporated into the concrete mixes at two different dosages (1% and 2%). Concrete mixes with compressive strengths of 40, 50, and 70 MPa were used to cast the samples. Specimen depth was also among the test variables, where prisms of depth 100, 150 and 200 mm were tested to study the size effect on the flexural behaviour of SFRC. Test results indicated that for the straight-end steel fibers, the increase in the fiber volume fraction from 1 to 2% had a noticeable effect on both flexural strength (or Modulus of Rupture, MOR) and associated prism mid-span deflection. However, for the hooked end steel fibers, there was only a limited increase in the same measured values due to reduced workability of the SFRC fresh mix. The test results also have shown that the increase in the concrete compressive strength had only a modest effect on the average MOR value, but a noticeable effect on average mid-span deflection at peak load. The latter was attributed to the relatively long length and the hooked end geometry of the steel fibers. Finally, test results revealed that specimen depth had an impact on the measured flexural strength, where increase in specimen depth was associated with reduced MOR values, a phenomenon that is commonly referred to in the literature as size effect.
Photo-voltaic Powered Electric Vehicle Fast Charger
Authors: Lai C P Y , Law K H , Lim K H 
Published: November 2020

Abstract
In the last years, dominant usage of petroleum-based transportation and consumption of fossil fuels results in greenhouse gas (GHGs) emissions into the atmosphere which causes negative impacts across the globe. As the situation worsens, more people are motivated towards opting for electrified transportation. However, there are still a lot of challenges to be overcome with one of the main issues concerning the development and availability of fast charging technologies in electric vehicles (EVs). To decrease high energy demand from the grid, usage of renewable energy systems (i.e., photo-voltaic) to fast charge EVs are preferred. In this paper, high performance DC-DC boost converter controlled by PI controller is proposed with the objective to mitigate the current state of fast charging and environmental problems. The proposed converter is able to generate different output power level based on the desired preset reference voltage value. All simulation results are documented to verify the proposed photovoltaic (PV) powered EV fast charger. For simplicity, EV batteries are being replaced with one resistor as the load whereas PV panels are used to generate input power for the converter.
Surface Engineering of Titanium Using Anodization and Plasma Treatment
Authors: Mallaiah Manjaiah , Kumar Gupta Ravi 
Published: November 2020

Abstract
Ti64 alloy is a well-known material for biomedical applications due to high corrosion resistance and biocompatibility properties. Surface properties of implants plays a vital role in bone and cell growth in the human body. With the anodization process, we can increase the surface porosity, which will be adequate for surface fascination of the implant screw to the bone and appropriate mechanical properties. Hence, the present study attempted to improve the surface properties of Ti64 by anodization and plasma treatment that may be promising method to increase the biocompatibility of Ti materials. Anodization process is the cheapest one to improve the surface properties of Ti alloy and riskless process. To intensify the open pores on the Ti64 surface plasma treatment was performed. Also, the aim of this study was to improve the aesthetic appearance of the dental implants and reproduce interference of colours. With the help of UV-VIS spectrophotometer the colour and spectral reflectance were investigated. The oxide layer thickness, chemical composition and nanosurface roughness was measured. These results suggests the surface modification of Ti64 alloy by anodization can produce interference of colours and are dependent on the applied voltage, oxide layer thickness. The surface oxidation consisting of anatase and rutile phase and change in nanosurface roughness, may improve the biocompatibility of Ti64.
The Mechanical and Thermal Properties of Polyurethanes/Precipitated Calcium Carbonate Composites
Authors: Lai Q Y , Yuhana N Y , Fariz S , Otoh M Z 
Published: November 2020

Abstract
The properties of polyurethane containing precipitated calcium carbonate (PCC) were studied. The PCC were produced from acetylene gas waste, and its usage as filler material for polymer were explored in this study. Present findings suggested the addition of 5 per hundred gram of PU(phr) significantly increases the shore A hardness to 39.2, in addition to improve the degradation mperature and specific gravity with decrease in water and oil absorptions capacity. The addition of 5 phr PCC to polyurethane improves the material structure and the morphology as calcium carbonate were dispersed when observed using microscopes. This research extends our knowledge of the addition of PCC to strengthen the mechanical and thermal properties of polyurethanes.
Finite Element analysis: Predicting cutting force in turning of Inconel 625 using ceramic tools
Authors: Reddy M M , William L C S 
Published: November 2020

Abstract
Inconel 625 is a unique material due to its characteristic properties of high strength at high temperatures, high corrosion and oxidation resistance. These unique properties thus pose a challenge to machine Inconel 625. Characteristics of work hardening in Inconel 625 generates high cutting force which results in poor surface finish and reduce the performance of cutting tool. Two-dimensional turning operation simulation is considered to evaluate cutting force in this research study. Box- Behnken design of experiment under Response Surface Methodology is used to identify the cutting force with 15 different combinations of cutting speed, feed rate and depth of cut parameters. Predictive mathematical model for cutting force is developed and obtained. From Analysis of Variance (ANOVA), depth of cut had significant influence on cutting force followed by feed rate and cutting speed. Optimization of cutting parameters was carried out and it is recommended that a low combination of depth of cut and feed rate should be selected with a high cutting speed to achieve minimum cutting force. The effect of rake angle on cutting force was investigated for ceramic cutting tools.
Telerobot: Failure Detection Using Imaging Technique for Piping Internal Surfaces
Authors: Hussein H.M.A. , Ramadan Aya A. A. , Kumar Gupta Ravi 
Published: November 2020

Abstract
Pipelines are the energy lifelines of almost every activity of everyday life. It is a safe way of transporting water, gas and oil over long distances. It is also the most practical way to deliver oil and gas across countries as being an extremely safe and economically viable solution to transport energy. Cracking and corrosion on the external and/or internal surfaces of in-service pipes, reduces the integrity of the material and potentially reduces the service life of the transportation system and equipment. Defects in pipelines may have various forms and may be initiated by one or more mechanisms potentially resulting in corrosion and/or cracking. In this paper we propose a system that detects the internal cracks in pipelines through a telerobot which can be inserted into the pipelines and detects the internal Failures (cracks) through a special modern high resolution digital camera and image processing techniques. The telerobot is a programmable and can be controlled as per the requirements such as speed and direction of the telerobot and sensors using mobile application and can be connected to a computer and smart phone. The telerobot captures a high definition images and also captures the precise location. These images are transferred to a computing facility for the analyses and to detect cracks.
Influence of flow limiter and grain shape factor of sand particles on erosion activity in pipeline
Authors: Tang Genevieve A T K , Foo Henry C Y , Tan I S , Yeong Y F , Lam M K 
Published: November 2020

Abstract
Erosion has been evaluated as the main cause of failure in pipework. The focus of this work is the effect of erosion activity on two-phase flow (solid-liquid) condition. Pressure distribution of liquid flow, velocity profile of liquid flow and trajectories of sand particles are scrutinized. Based on the experimental data, different limiter pipeline was simulated to validate the data and an overall grain shape factor of 0.265 was obtained. From the qualitative and quantitative analysis of grain shape factor (GSF), it was identified that the 75 % of sand are composed of high sphericity particles (GSF=0.2), 25 % of sand composed of slightly lower sphericity particles (GSF=0.45). For the simulation work, the fluid flow rate, grain shape factor and sand concentration is altered ranging between 25 litres/s to 50 litres/s, 0.2 to 1.0 and 0.5 % to 1.0 % respectively. Through ANOVA analysis and it demonstrated the significant influence on erosion activity in descending order (fluid flow rate > shape factor > sand concentration). After numerical optimization, the minimum erosion activity on limiter was obtained by obeying the settings of fluid flow rate, shape factor and sand concentration as 50 litres/s, 0.2 and 1.0 % respectively.
Performance evaluation of horizontal flow constructed wetlands as primary and secondary treatment for university campus wastewater
Authors: Yong Tan Yee , Tang Fu Ee , Lee Ing Ho Carrie , Shu Zhen Wong Madeline 
Published: November 2020

Abstract
Horizontal flow constructed wetland (HFCW) is an attractive green technology for wastewater treatment. In the present study, four laboratory-scale HFCWs were constructed to serve as the primary and secondary treatment of university campus wastewater. The effect of hydraulic residence time (HRT) and pre-aeration of influent were investigated. The experimental results demonstrated that the wetland vegetation played an important role in the oxygen restoration and the influence of pre-aeration was minor. In the primary treatment, effective removals of TSS and NH4-N were observed. However, the treatment of BOD and NO3-N were insignificant due to the low influent concentrations. As for secondary treatment, the HFCWs effectively reduced the concentrations of BOD, NH4-N, and NO3-N in the effluent from the Intermittent Decanted Extended Aeration (IDEA) plant. The effluent quality of all HFCWs complied with the Standard A sewage discharge. Longer HRTs brought a positive effect to the removals of organic matter and nitrogen.
Dynamic Simulation of Hydrogen Iodide Decomposition in Catalytic Multi-Tubular Reactor
Authors: Nandong Jobrun , Sirajul Akmal , Mohd Noraini 
Published: November 2020

Abstract
Sulfur-Iodine thermochemical cycle process has been considered a promising method to generate hydrogen from water. One of the main limitations of this process lies in the hydrogen iodide decomposer section, which requires substantial amount of heat at high temperature. The present study analyses the heat transfer limitation effect on the performance of hydrogen iodide decomposition in a multi-tubular catalytic reactor by means of dynamic simulation. The extensive numerical simulation shows that the inlet temperature heating medium (Helium gas) should be at least 700°C so to enable at least 90% conversion when the inlet molar fraction of hydrogen iodide is 0.6. Lowering the inlet heating medium will require the reduction in the inlet molar fraction of hydrogen iodide in order to keep the conversion at 90% and above.
Numerical analysis of erosion pattern on pipe elbow bend with swirling flows
Authors: Yam K S , Roy S , Lee V C C , Law M C 
Published: November 2020

Abstract
Abrasive solid erosion is a common issue faced in many industrial applications and can incur significant loss to production efficiency. In a piping system, the bends are generally the most vulnerable to the abrasive erosion due to the abrupt change of flow. Reducing the erosion at the bend is key to industries for safety purpose and ensure equipment longevity. This research focusses on the effectiveness of utilizing the swirling flow in reducing the erosion rate at the elbow bends. Numerical approaches are adopted to systematically evaluate the impact of the degree of swirling in the flow on the erosion reduction at the elbow. The results demonstrate the promising prospect of the swirling flows as a mechanism to control the erosion at the pipe elbow.
Supply Chain Performance Analysis With Data Envelopment Analysis in TBBM PT. Pertamina Boyolali
Authors: Hanif Z , Kristy P , Utami M W D , Yuniaristanto  , Sutopo W 
Published: November 2020

Abstract
PT. PERTAMINA TBBM Boyolali is a supplier of fuel oil in the form of premium, pertamax and diesel. The company should distribute fuel products using tank cars with operating areas covering Boyolali, Surakarta, Karanganyar, Sukoharjo, Sragen, Klaten, Wonogiri, Ngawi, Pacitan, Magetan, Ungaran, Semarang, Salatiga, Purwodadi, and Blora. An efficient supply chain is needed to provide the right products and services, with the specifications needed, in the right place and to the right customers. This article aims to find out and analyze the efficiency that occurs at operational TBBM Pertamina Boyolali and to find out the variables that most influence supply chain performance to be analyzed and improved so that improvements in supply chain performance can be more focus and optimal. The Decision-Making Units (DMUs) stated in this article are the period of supply chain activities from January 2018 to November 2018 at TBBM Pertamina Boyolali, the number of DMU is 11 DMUs. Supply Chain Operation Reference (SCOR) method with responsiveness, flexibility, and reliability attributes is used to measure Supply chain performance. To analyze supply chains efficiency, this article applies input-oriented DEA CCR (Charnes, Cooper, and Rhodes) model which considers linear relationships in its input and output. Data Envelopment Analysis (DEA) is a strong tool for measuring the efficiency of the DMUs and does not need to normalize indicator values that have different dimensions. The software used for processing data in this article is Banxia Frontier Analyst 4.2. This article provides suggestions for improving cash-to-cash cycle time, lead time, and flexibility for more efficient fuel distribution.
Six Sigma Application to Minimize Castor 5 Inch Scrap Material in EOP Warehouse: A Case Study
Authors: Fajrianto A , Asnan M H I N , Khofiyah N A , Sutopo W , Yuniaristanto  
Published: November 2020

Abstract
Case study in this research at PT. Mega Andalan Kalasan, which one of the manufacturing companies engaged in manufacturing hospital equipment that often has problems regarding the quality of materials stored in warehouses. The problem is often found in the 5 Inch castor material that becomes scrap and incurs costs so that waste occurs. Based on data from April 2018 to September 2018, the percentage of scrap material is increasing every month from 1.44% to 1.77%. Due to these problems, the purpose of this research is to minimize the 5 Inch castor material which is a scrap to avoid waste costs in the Export Oriented Product Warehouse Unit of the company. The methodology in this study uses the Six Sigma method, namely by implementing the Define, Measure, Analyze, Improve, and Control (DMAIC) stages. The results obtained are the most dominant cause of scrap castor 5 Inch material is storage of material on a rack that is not organized with an RPN value of 240. Thus, it is necessary to make improvements to minimize the scrap castor 5 Inch material by conducting a routine briefing by the PIC Area Warehouse Unit Export Oriented Product before operational activities begin.
Redesign Determination of Plat Raw Material Supplier with Analytic Hierarchy Process (AHP) Approach: A Case Study
Authors: Hidayati K A , Rosanti A A , Khofiyah N A , Sutopo W 
Published: November 2020

Abstract
PT. XYZ is a company in the newspaper industry. The selection of suppliers so far is only based on the price offered and the promised delivery speed. The price offered by the supplier is also influenced by the exchange rate of the rupiah against the dollar resulting in price fluctuations in the purchase price of raw materials. Even though the price of raw materials has increased, newspaper prices have remained the same, and to avoid this problem, the company has supplied raw materials from many suppliers. The company has made good cooperation with several suppliers, but does not yet have the right supplier selection method and can be applied with a good planning process. Therefore, companies need to select suppliers with the right methods so that raw material orders are optimally fulfilled and get the best suppliers who can work together in the long run. In this study, the determination of the best suppliers is carried out on the raw material of the plate as well as important criteria in the selection of these suppliers . Data collection is done using interviews, questionnaires, and literature studies. Based on the results of data collection, among others, the purchase price, delivery time, maximum number of orders, the level of disability, and the distance of the supplier with the company. Data processing uses one of the MCDM (Multi Decision Making Criteria) methods, namely AHP (Analytic Hierarchy Process). With the results of supplier one being designated as the best supplier. This can be known with the highest final value in the final AHP calculation, with a value of 3.95643, and the criteria most considered in determining suppliers is the bid price.