bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved bounds on the Radio degree of a cycle
Authors: Vanam Radha Ramani , Meera K. N. , Dhanyashree  
Published: December 2019

Abstract
A labeling f : V (G) → Z
+ such that |f(u)−f(v)| ≥ diam(G)+1−d(u, v) holds for every pair of vertices, u, v ∈ V (G), is called a radio labeling of a graph, G. The radio degree of a labeling, f : V (G) → {1, 2,… |V (G)|} in a graph, was defined by the same authors as the number of pairs of vertices u, v ∈ V (G) satisfying the condition |f(u) − f(v)| ≥ diam(G) + 1 − d(u, v) and was denoted by rdeg(f). The maximum value of rdeg(f) taken over all such labelings was defined as the radio degree of the graph, denoted by rdeg(G). The radio degree of some standard graphs like paths, complete graphs, complete bipartite graphs, wheel graph and fan graph was completely determined and a lower bound on the radio degree of cycles was obtained. In this paper, the authors have obtained better bounds on the radio degree of a cycle.
AMS Subject Classification number: 05C78, 05C12, 05C15
Drug Entrapment Efficiency of Silver Nanocomposite Hydrogel
Authors: Giridhar Reddy S. , Thakur Amrita 
Published: December 2019

AbstractSilver nanocomposite hydrogel (SNH) with biodegradable polymers, sodium alginate and sodium lignosulphonate was synthesized employing principles of green chemistry for possible application in the field of controlled drug release. One of the factor that determines the release of drug from blend is the quantity of drug present/trapped inside the polymer network. The entrapment of drug in the polymer matrix depends upon the stability of matrix and interaction between the drug and the matrix. In the present study effect of presence silver nanoparticles in the polymeric matrix on the Drug Entrapment Efficiency (DEE) for the drug ciprofloxacin (CPX) was investigated. The drug entrapment efficiency for CPX loaded beads of SA/LS was calculated for similar conditions, to evaluate the effect of silver nanoparticles. Experimental results confirmed role of crosslinking and presence of silver nanoparticles on the stability of SNH and its entrapment efficiency. Observations indicate that the drug entrapment is more for the SNH as compared to the blend. Presence of silver nanoparticles help stabilize the polymer matrix, improves binding inside the matrix, which leads to the better drug entrapment.
Prediction of Cutting Forces Experimentally in End Milling Process Using Inverse Analysis
Authors: Patil Ratan A , Gombi S L 
Published: December 2019

Abstract
Milling is a versatile manufacturing process which is used in machining many types of complex geometry parts, which has become the prior subject for many research studies. This paper provides study on cutting forces on end milling during machining. The study deals with the indirect measurement of cutting forces during machining using frequency response function (FRF). The problem of determining the unknown force acting on a body or a structure is the inverse problem. The cutting forces acting on a tool can be estimated by the responses measured at different points when the tool comes in contact with the work piece. The accuracy of the method can be improved by using singular value decomposition method and Moore Penrose pseudo inverse method. The experimental method results in better identification of cutting force which helps in optimum design and development of cutting tools. Statistical analysis helps in knowing the level of significance of the proposed method.
A Comparative Study on Mechanical Properties of Kenaf Fiber-Reinforced Polyester Composites Prepared by VARI, RTM and CM Techniques
Authors: Suresh Babu A , Gowthamraj S , Jaivignesh M 
Published: December 2019

Abstract
This work aims at comparing the mechanical properties of composite laminate fabricated by three different fabrication processes. Kenaf fiber polyester composite laminates were fabricated by compression moulding technique, Vacuum assisted resin infusion process (VARI) and Resin transfer moulding process (RTM). Vacuum assisted resin infusion (VARI) process bridges the gap between labour intensive compression moulding process and capital intensive Resin transfer moulding (RTM) process. The mechanical properties such as tensile, flexural and impact behaviour were studied. Vacuum assisted resin infusion process showed improved tensile and flexural strength as compared to resin transfer moulding process and compression moulding (CM) process. On the other hand, impact strength of VARI composites is slightly lower than that of RTM and CM composites. From the study, it was found that mechanical properties increase with increase in fiber content and uniform distribution of resin in the matrix. The void content and water absorption properties were evaluated and found to be maximum for the compression moulded composites.
An Ant Colony and Simulated Annealing Algorithm with Excess Load VRP in a FMCG Company
Authors: Srinivas Rao T 
Published: December 2019

Abstract
Fast moving consumer goods pose a major research problem as the objective is to reach the customers in an efficient manner. The delivery of goods to consumers must reach quickly without any hurdles. We assume that the FMCG companies have multiple number of warehouse hubs to reach its vast majority of consumers. Sometimes a single vehicle may not be enough to complete the tour, hence we may require another small vehicle to reach the small set of customers. The above problem has been modelled as a supply chain vehicle routing model. In our paper we have used ant colony and simulated annealing algorithm to discuss the above problem and compare their efficiencies.
Experimental Investigations on Rectangular Dielectric Resonator Loaded on a Microstrip Line
Authors: Narayanan Vipin , Sahajan Arjun , Menon Sreedevi K 
Published: December 2019

Abstract
This paper is an analysis of the filter characteristics of a rectangular dielectric resonator (DR) loaded on a Microstrip Line (MSL). Position of the rectangular DR on the Microstrip Line is optimized for best performance of the filter and different orientations of the dielectric resonator are tried out for finding the optimized orientation and position. For efficient coupling between MSL and DR a metallic patch is provided at the bottom of dielectric resonator with the same dimension as the surface touching the feedline. Experimental studies carried out ascertain, the proposed DR loaded on MSL is an effective filter.
Carbon Quantum Dot-Polypyrrole Nanocomposite for Supercapacitor Electrodes
Authors: Sagar Mittal Shiva , Ramadas Gouri , Vasanthmurali Nandika , Madaneshwar V S , Sathish Kumar M , Kothurkar Nikhil K 
Published: December 2019

Abstract
A CQD-polypyrrole composite was developed as a supercapacitor electrode material. Carbon quantum dots (CQDs) were synthesized using citric acid as carbon precursor. The CQDs were incorporated in a polypyrrole matrix by dispersing them during the in-situ polymerization of pyrrole. The structure and morphology of the composite were characterized using FT-IR, XRD, TEM. Cyclic voltammetry and galvanostatic charge-discharge studies were performed using a three-electrode system to understand the electrochemical behaviour of the sample. The composite showed a 33% increase in the specific capacitance as compared to neat polypyrrole.
Determination of the dislocation-based mechanism(s) responsible for the anomalous ductility of a class of B2 intermetallic alloys
Authors: Agnew S R , Ungar T 
Published: December 2019

AbstractA class of stoichiometric, ordered MR alloys (where M denotes a metal and R either a rare earth or group IV refractory metal) with B2 (CsCl) crystal structure, were discovered to possess anomalous ductility by researchers at Ames Laboratory in the early 2000’s. Despite active research on the topic for over 15 years, a holistic explanation for the anomalous ductility of these metal alloys has not yet been accepted by the scientific community. The reason for this appears to be a failure to account for all relevant length scales. Researchers either focus on theatomisticlength scale relevant to dislocation core structures, themicroscopiclength scale of dislocations and dislocation ensembles, themesoscopiclength scale of grains and their interactions, or themacroscopicscale of mechanical testing samples with millimetre dimensions or larger. Focused studies at each of these length scales have provided essential, but insufficient information to provide a complete answer to the question. The insight provided by in-situ diffraction studies, along with crystal plasticity modelling as an interpretive tool, and a novel grain-by-grain line profile analysis technique for assessing dislocation densities in polycrystals is highlighted. In addition to the primary <100> dislocations, which are most easily activated in all of these anomalous MR alloys, the results show that dislocations with large Burgers vectors (e.g., <110> and <111>) are present in large numbersbeyond a transitionin the strain hardening response. The motion of these large Burgers vector dislocations is experimentally observed to occur at stress levels consistent with atomistic modelling predictions of the Peierls resistance and simultaneously provides a satisfying explanation for the anomalous ductility and other experimental results.
Understanding the evolving state of deforming polycrystals using synchrotron x-rays
Authors: Miller Matt , Budrow Chris , Long Tim , Obstalecki Mark 
Published: December 2019

Abstract
The multiscale nature of irreversible processes like plasticity make them particularly challenging. One must be looking everywhere, all the time to gain a predictive understanding of plasticity–related processes such as fatigue crack initiation. High energy (HE) synchrotron x-ray diffraction is a unique tool for characterizing the state of an entire aggregate of metallic crystals with sub-crystal resolution. Combined with in situ loading, HE x-ray diffraction provides experimental hope for characterizing the conditions leading to the initiation of a crack. In this work, we conducted a HE x-ray diffraction experiment on a commercially pure copper sample subjected to in situ cyclic loading at the F2 Station at the Cornell High Energy Synchrotron Source (CHESS). We observed that the evolution of lattice orientation distributions within each crystal evolved as the specimen was loaded through complete fatigue cycles. We defined a “size” of these orientation clouds, which we called

Θ
¯

. Changes in

Θ
¯

are related to the plasticity-induced state of each crystal. We saw significant evolution of the

Θ
¯

distributions as the sample went through cycle 2. By cycle 256, the evolution of the

Θ
¯

distribution was significantly reduced - consistent with the saturation of cyclic hardening that we see on the macroscale. We also saw that the 40 crystals with the largest values of

Θ
¯

in the first half cycle had a larger amount of

Θ
¯

accumulation on average over the 256 cycles than the rest of the crystals in the aggregate.
Following Microstructures during Deformation: In situ X-ray/Neutron Diffraction and HRDIC
Authors: Polatidis E , Sofinowski K , Hsu W-N , Swygenhoven H Van 
Published: December 2019

Abstract
The mechanical behavior of three engineering materials is studied employing in situ deformation methods. The study covers metastable austenitic steels with different stacking fault energies during multiaxial loading, a Ti-6Al-4V alloy processed by electron beam melting during uniaxial deformation and a commercial nanocrystalline NiTi alloy during multiaxial deformation. The experimental results obtained by in situ X-ray or neutron diffraction elucidate the load transfer and phase transformation mechanisms, information that is averaged over a relatively large volume containing a statistically representative number of grains. Complementary in situ high resolution digital image correlation allows details to be revealed regarding the localized strain accommodation and slip activity with a sub-grain spatial resolution. It is demonstrated that the synergy of the different length-scale investigations provides a better understanding of the complex relationship between microstructure and deformation behavior in these materials.
Rich multi-dimensional correlative imaging
Authors: Withers Philip J , Burnett Timothy L 
Published: December 2019

AbstractThe use of microstructural design to tailor materials properties has increased sharply in recent years. In parallel the number and the capability of techniques able to characterise materials microstructures has increased sharply too providing structural, chemical and crystallographic information. Here we examine how correlated 3D, 4D (3D + time) and multi-dimensional imaging enable a much richer picture to be built up of a materials microstructure. We look at how a data-centric approach can support the use of materials informatics, digital twinning and machine learning to accelerate the design of new materials systems and to optimise the manufacturing of established ones. However for this to happen we need to develop ways to digitally fingerprint the microstructural images and maps we collect such that they can be incorporated into machine learning schemes. Through the use of case studies (multimodal imaging) we look at correlative imaging across scales, across time (the dilation of electrode materials in lithium batteries during discharging and fast corrosion of magnesium), as well as across multiple modalities (butterfly defects in bearings steels and the sintering and recrystallization of powders). These demonstrate how different techniques can come together to provide complementary aspects of the bigger picture.
An efficient method to improve the spatial resolution of laboratory X-ray diffraction contrast tomography
Authors: Fang H , Jensen D Juul , Zhang Y 
Published: December 2019

Abstract
Lab-based diffraction contrast tomography (LabDCT) has recently enabled nondestructive 3D characterization of the crystallographic orientations and grain morphologies in bulk materials. Despite the wide accessibility and availability of lab-based X-rays, the current spatial resolution of LabDCT is only about 20 μm and has to be improved to make this technique a more versatile tool. Conventional LabDCT takes advantage of the Laue focusing effect, i.e. the diffracted beam from a sample illuminated by an incoming polychromatic beam, is focused when the source and the detector are symmetrically positioned. In this study we have investigated the possibility of increasing the spatial resolution of LabDCT by placing the detector at a distance beyond that required for Laue focusing. We first developed a forward projection simulation tool to elucidate the effects of placing the detector at a larger distance. Next, we performed LabDCT measurements on a partially recrystallized pure aluminum sample at different sample-to-detector distances. The results show that the diffraction spots can be magnified by a factor of about three compared to the current LabDCT setup. The benefits and limitations resulting from increasing the sample-to-detector distance are discussed.
Statistics and Reproducibility of Grain Morphologies and Crystallographic Orientations Mapped by Laboratory Diffraction Contrast Tomography
Authors: Sun Jun , Oddershede Jette , Bachmann Florian , Bale Hrishikesh , Lauridsen Erik 
Published: December 2019

Abstract
Laboratory diffraction contrast tomography (LabDCT) enables a user to reconstruct 3D grain maps of polycrystalline materials non-destructively. For each grain, the morphology and crystallographic orientation, as well as derived properties such as grain boundary properties can be determined. Through two application examples this paper demonstrates the capabilities and potential of the current LabDCT implementation. Firstly, for well-annealed grain structures the reproducibility of LabDCT for more than 95% of the grains was found to be 5 μm on grain center-of-mass positions and 0.02° on orientations, while 90% of the grain boundary locations are determined with an accuracy better than 4 μm. The second example highlights the available statistics on thousands of grains, as well as the complementarity between LabDCT and absorption contrast tomography, readily available due to the integration of LabDCT on a commercial X-ray microscope
Ultrafine-grained Tungsten by High-Pressure Torsion – Bulk precursor versus powder processing route
Authors: Wurmshuber M , Doppermann S , Wurster S , Kiener D 
Published: December 2019

Abstract
The continuous enhancements and developments in the field of power engineering, as well as the uprising of nuclear fusion technology, demand novel high performance materials featuring exceptional strength and damage tolerance as well as durability in harsh environments. Ultra-fine grained bulk materials fabricated by high-pressure torsion, exhibiting a grain size less than 500 nm are promising candidates for these applications. Tungsten, the material of choice for plasma-facing materials in fusion reactors, is expected to exhibit even more enhanced properties by precise doping with impurity atoms, strengthening grain boundary cohesion. In order to allow this meticulous control of chemical composition, in-house mixing of the raw material powders is preferable to use of commercially available alloys. Several challenges arise in powder processing of tungsten via high-pressure torsion, originating in the intrinsic strength and high melting point of the material, and in the affinity of the powder to oxygen. Strategies to overcome these problems will be addressed in this work. Furthermore, we compare ultra-fine grained tungsten produced from a bulk precursor to that from the developed powder approach regarding microstructural features, hardness and rate-sensitive properties. The powder route showed promising and widely comparable results to the material processed from bulk tungsten, rendering it an effective way for fabricating ultra-strong tungsten, while keeping the additional ability to accurately control chemical composition and tailor grain boundary segregation states.
A unified model for microstructural coarsening of deformed metals
Authors: Yu T 
Published: December 2019

Abstract
In this work the kinetics of continuous coarsening of deformation microstructures are analysed. The coarsening examples span a large range in structural scale and driving force, including subgrain growth in a deformed subgrain structure, uniform coarsening in a deformed lamellar structure, and grain growth in a deformed nanocrystalline structure. The unified coarsening model for deformation microstructures considers the change of the apparent activation energy during coarsening and successfully describes the kinetics in each of the given coarsening examples. It is also found that the increase in the apparent activation energy dominates the coarsening kinetics and leads to a significant decrease in the coarsening rate as coarsening proceeds.
Coarsening in nanocrystalline thin films: A 4D problem
Authors: Öncü A. , Zöllner D. 
Published: December 2019

Abstract
Materials properties of polycrystalline solids depend strongly on the microstructure. Hence, investigating grain microstructures as they change during grain growth, e.g., by thermal annealing, is of utmost importance. Historically, this has been done by optical microscopy yielding only a two-dimensional characterization. Consequential problems have long been recognized. In particular, a two-dimensional section through a three-dimensional polycrystal yields a rather poor idea about the true size and form of the individual grains, and therefore of the microstructure, and in addition, such a section represents only a snapshot in time and does not give any clues about structural changes during grain growth. In the present study, we investigate coarsening in nanocrystalline thin films using a modified three-dimensional Potts model. By taking the increased importance of higher order grain boundary junctions, i.e. triple lines, at smaller grain sizes into account, it is shown that the microstructure, as well as the associated growth kinetics, undergo distinct changes during coarsening.
The strength of the hull on a high longitudinal wave
Authors: Suvorov Vladimir , Bahrami Mohammad Reza 
Published: December 2019

Abstract
The paper presents the method for calculating the strength of the ship vessel on the longitudinal wave, based on the modern theory of the beam and computer mathematics. It consists of two parts, which are the determination of hydrodynamic loads on the hull during the passage of a wave and the calculation of the stress-strain state caused by the ship vessel as a beam. The main feature of the technique is that the loads and deflection are considered simultaneously, which was made possible by computer mathematics. The developed method allows; increasing the accuracy of calculations of ship hulls for durability, has a relatively low cost, and does not require expensive software.
Three-dimensional vibrations of wind turbines
Authors: Andriushchenko Ekaterina , Meshkov Aleksandr 
Published: December 2019

Abstract
In this paper authors consider three-dimensional vibrations of a wind energy farms (WEF) of tower type VTR 50 Arctic. Low-frequency vibration of a WEF composed of a tower and rotor is considered in the out of balance condition. The method of analysis is based on the theory of mechanical oscillations and the theory of elastic shafts. We consider the tower as a shaft and the rotor as a rigid body. Using the Lagrange’s equations for elastic structures in combination with computer simulation provides for the novelty and efficiency of the suggested method. The unique nonlinear equation is deduced and solved using the Wolfram Mathematica.
Vibration analysis of skidding tractor with an operator during raising–lowering a tree
Authors: Bahrami Mohammad Reza , Wasilewski Mark , Abed Salam Ahmed 
Published: December 2019

Abstract
The aim of this article is to develop mathematical models that help at the design stage of design documentation for a skidder to determine the upcoming dynamic loads on the machine, the vibration effect on the machine and the operator, and scientifically based parameters to ensure their reduction. Vibration analysis and prediction of the skidding tractor with an operator allows predicting adverse events, prevent accidents, avoid costly and dangerous experiments, as well as optimize the design and operating modes. A particularly important degree of vibration loads affects the performance and health of the operator. The constant long-term effect of vibrations leads to increased operator fatigue and an increase in the number of errors in control. As a result, operator productivity significantly reduced. Baseline data that used in this article is related to the skidding trailer tractor TB-1M. So the results of this research may use as the foundation of future works for omitting vibration influence on the operator by designing active and smart dynamic vibration absorber for a different type of tractors. In addition, the effect of sitting stiffness and loading on the operator-tractor system have been investigated.
Area determination of correct operation of the vibrofuge
Authors: Krokhmal Vladislav , Klyukin Valeriy 
Published: December 2019

Abstract
The object of the study is a centrifuge, on the rotor of which a pneumatic spring with a mechanical vibrator is fixed. The operation of the pneumatic spring during rotation of the centrifuge rotor and the operation of a mechanical vibrator with varying plant parameters is analyzed. Identified parameters that significantly affect the operation of the plant. The areas of parameters in which the correct operation of the plant is observed are found.
The use of artificial intelligence to control the processes of welding and direct arc growth under the influence of disturbing factors
Authors: Pereverzev A.E. , Ivanova I.V. , Maystro Alexey , Zarubin I. A. , Panfay Wan 
Published: December 2019

Abstract
We develop a method to improve the quality of welded joints and process performance in arc welding and direct arc growing under the influence of disturbing factors based on the use of artificial intelligence.