omniomni/omni-engineering huggingface dataset:
Isothermal Thermogravimetric Analysis (TGA) is a technique in which the mass of a substance is monitored as a function of time as the sample specimen is subjected to a controlled temperature program in a controlled atmosphere. In this research, isothermal TGA was carried out to determine the thermal stability of the recycled epoxy-based and vinyl ester-based carbon fiber composite (CFC). The specimens were heated at constant temperature under nitrogen and air. We evaluate the influence of different temperature on the degradation of recycled CFCs. Results indicate that different temperature has significant influence on the degradation of the recycled CFC under nitrogen. This work is licensed under Creative Commons Attribution 4.0 License AJES.MS.ID.000510 Figure 1: Isothermal TGA curve of epoxy-based CFC recorded in nitrogen (considering the influence of temperature). Academic Journal of Engineering Sciences Volume 1-Issue 2 Citation: Seyed Hossein Mamanpush, Reyhaneh Tavousi Tabatabaei, Bahareh Tavousi Tabatabaei. Isothermal Thermogravimetric Analysis of Recycled Carbon Fiber Composites. Acad J Eng Sci. 1(2): 2018. AJES.MS.ID.000510.Page 2 of 2Figure 2: Isothermal TGA curve of vinyl ester-based CFC recorded in nitrogen (considering the influence of temperature). Figure 3: Isothermal TGA curve of epoxy-based CFC recorded in air (considering the influence of temperature). Figure 4: Isothermal TGA curve of vinyl ester-based CFC recorded in air (considering the influence of temperature). Isothermal TGA results of epoxy-based CFC shows similar trend (Figure 3 & 4). After 25 Min. the remaining of epoxy-based CFC is 88%, 85%, 83% and 82% at 340 °C, 360 °C, 380 °C and 400 °C respectively. Isothermal TGA results of vinyl ester-based CFC indicates that by increasing the temperature degradation happened faster. After 25min, the vinyl ester-based CFC has the remaining of 77% for almost every temperature. The isothermal TGA results of recycled CFCs is a key factor for manufacturing the second-generation composites from recycled materials. Isothermal TGA results of epoxy-based CFC and vinyl ester-based CFC indicate that there is a safe zone for processing these materials. For all the samples isothermal results is almost consistent after 7min. and no degradation happened after that. Acknowledgement None. Conflict of Interest No Conflict of Interest.
Lattice con/f_iguration is a core parameter in Lattice-Boltzmann (LB) methods, both from theoretical and implementa- tion standpoints. As LB methods have progressed over the past decades, a variety of lattice con/f_igurations have been proposed and referred to according to a plurality of lattice nomenclature systems that usually include the Euclidean space dimensionality , the lattice velocity count and, in fewer instances, the discretization order in their format. This work surveys lattice nomenclature systems, or lattice naming schemes, along the history of LB methods, starting from their Lattice Gas Automata (LGA) predecessor method, up to the present time. Findings include multiple lattice categories, competing naming standards, ambiguous names particularly in higher-order models, naming systems of varying model parameter scopes, and lack of unambiguous naming schemes even for space-/f_illing, Bravais lattice types. Keywords lattice-Boltzmann stencils — lattice-Boltzmann models — lattice nomenclature systems — high-order lattices. Highlights Surveys lattice nomenclature systems in the history of LBM: from the LGA to current times — Discusses lattice categories, competing standards, naming ambiguity, model parameter scope. /one.lfAdjunct Professor. Universidade Tecnol ´ogica Federal do Paran ´a – UTFPR, C ˆampus Guarapuava. Grupo de Pesquisa em Ci ˆencias T ´ermicas. /two.lfUniversidade Tecnol ´ogica Federal do Paran ´a – UTFPR, C ˆampus Guarapuava. Grupo de Pesquisa em Ci ˆencias T ´ermicas. ?Corresponding author : NaaktgeborenC ·PhD a gmail ·com License https://creativecommons.org/licenses/by/4.0/ Contents /one.lf Introduction /one.lf /two.lf Lattice Nomenclature Survey /one.lf /two.lf./one.lf Lattice-Gas Automata Lattice Designations . . . . . . /one.lf /two.lf./two.lf Early Lattice-Boltzmann Y ears . . . . . . . . . . . . . . . /two.lf /two.lf./three.lf The Y ear of /two.lf/zero.lf/zero.lf/six.lf . . . . . . . . . . . . . . . . . . . . . . . . /three.lf /two.lf./four.lf Higher-order lattice proliferation . . . . . . . . . . . . . /four.lf /three.lf Discussion /six.lf /four.lf Citations by Year /seven.lf /five.lf Conclusions /seven.lf
- With the automotive industry offering diverse vehicles to cater to various needs, selecting the ideal car becomes challenging. The study highlights the rising significance of cars as a necessity, exemplified by India's car ownership rate. The paper employs a Multi -Criteria Decision -Making (MCDM) approac h, focusing on cost, safety, comfort, and performance, with 14 sub -criteria, for a comprehensive evaluation structure. The research employs Fuzzy AHP and Fuzzy TOPSIS methods to handle the uncertainties inherent in decision - making processes. These techniques integrate fuzzy set theory to realistically capture real -world complexities. The goal is to systematically evaluate and choose cars based on individual p
16 Significant use of forest biomass in the iron and steel industry (ISI) to mitigate fossil CO 2 emissions 17 may impact biomass availability for other users of the same resource . Increased competition for 18 biomass will likely have an effect on both the price of forest biomass assortments and on the 19 economic feasibility of the ISI’s investment s in biomass utilisation . This paper explores the market 20 effects of increased biomass competition and the interactions between the ISI and the forest 21 industry se ctors. A soft -linking approach is employed that combin es a spatially explicit techno - 22 economic energy system model and a partial equilibrium model . This allows for new equilibrium 23 price developments for different feedstock assortments to be endogenously mod elled in a dynamic 24 and iterative process. The results show that regional price disruptions caused by the ISI’s new 25 biomass use affect geographical p
Discoveries come about in one of two ways. In one, an enquirer discovers something which amounts to connecting the dots in the ocean of existing knowledge , domain of reason . We call them Type I discoveries. In the other, the discovery made cannot come about on the basis of the then existing knowledge. We have coined the name, Type II discoveries for such discoveries . Since ancient times, Type II discoveries have been aptly called, “ Shruti ”, meaning, revealed in Sanskrit . Type I discoveries can occur when the focus of attention is enhanced, as in deep contemplation, while Type II discoveries can occur when the focus of attention is further enhanced, as in a deep ly meditative state , or in devotional prayer , transcending reas on. The article cites
Achievement of some of the United Nation’s Sustainable Development Goals will not be possible if global trends in pollution associated with petrochemical -based plastics continue. Alternatives to petrochemical plastics have been researched intensely , but th ey have not been developed to replace current plastic products in a commercially viable way. The demand for single -use plastic personal protective equipment created by the COVID -19 pandemic has stimulated urgency in developing pollution prevention strategies that transcend reliance on highly variable consumer behavior. Biological material plastics are potentially sustainable because their manufacture u tilizes renewable resources , and they are biodegradable. In this paper , challenges facing the sustainable management of discarded single -use petrochemical plastics are discussed , and a material lifecycle perspective is proposed that would be integrated into a circular economy of biological plastics . Preventing petrochemical plastics pollution requires a shift to fossil - free feedstock and energy and the design of bi opolymers with desired properties. In this Manuscript Click here to view linked
. The Transfer Matrix formalism is ubiquitous when it comes to study wave propagation in various strati ed media, applications ranging from Seismology to Quantum Mechanics. A relation between variables at two points in two di erent layers can be established via a matrix, termed (global) trans- fer matrix (product of \atomic" single-layer matrices). As a matter of con- venience, we focus on 1D propagation of axial waves in rods, but our results extend to other elds where the formalism applies. When the layering cor- responds to a representative repeated cell in an otherwise in nitely periodic medium, the trace of the cumulative multi-layer matrix is known to control the dispersion relation. It is proved that this trace has a discrete spectrum made up of distinct 2N1harmonics (not necessarily orthogonal to each other in any sense) which are exactly characterized in terms of both the frequency of their oscillations and their amplitudes; the phase shift among harmonics is either zero or . This de nite appraisal of the discrete spectrum of the trace opens new strategies for rational design of bandgaps, going beyond parametric or sensitivity studies. 1.Introduction 1.1.Ubiquity of Transfer Matrix formalism. The Transfer Matrix method, in its two-variable variant, refers to an approach to solve two coupled scalar linear 1st- order ODEs with two scalar unknowns, by, instead of looking to combine equations into one, recasting them into a single linear 1st-order vector ODE, where the entries of the unknown vector correspond to the original scalar unknowns. Let us mention some of the branches of Physics and Engineering where this method has been applied, along with some useful
Theauthorofthispaperisproposingastructuredesignthroughwhichpushmepullyouboatcan beusedtogenerateelectricity. Keywords Pushmepullyou,Blackford,CFD,Catia,Ansys. Introduction PushmepullyouboatisanovelinventionbyB.L.Blackford[1]whichmovesattwicethevelocity ofairpushingitperpendiculartoitsmainwingsafteracertainconditionhasbeenmet.Thispaper documentsthedesignandanalysisofastructurethatiscapableofusingthisinventiontogenerate electricityatpossiblyhigherefficiencythanwindturbinesusedaroundtheworldasoftoday. Design and analysis The concept is to keep multiple push me pull you boats attached to an axis tangentially and over wateronacircularpath.Theentirestructurethentobecoveredandafunneltoincreaseincoming airvelocity.Infigure1belowtwotypesofinlet,oneelevatedandotheratgroundlevel.Eachhave three types of outlets and CFD analysis results have shown 5-15 times increase in velocity, howevernocleardistinctionhavebeenmadeasshowninfigure2. Figure1 Figure2 Resultsofanalysingairspeedandpressureextertedonwallswithrespecttoinletspeedhasbeen onlyperformedononetypeofdesign.Figure3&4belowshowtheresultsof1m/sinletvelocity asvelocitystreamlineandpressurecountourrespectively. Similarly, figure 5 & 6 show results of 5 m/s and in figure 7 & 8 results of 10m/s inlet velocityhasbeendepicted. Figure3(1m/s) Figure4(1m/s) Figure5(5m/s) Figure6(5m/s) Figure7(10m/s) Figure8(10m/s) In figure 9 & 10 , artistic liberty has been taken to illustrate the boats, axis, water, paint (for erosion),concretebaseandenclosure. Figure9 Figure10 Conclusion Considering the thrust produced and the angle between tangential boats and wind velocity, the designcanbefurtherdevelopedintoprototype.Whileontheotherhandpressurecountersonwalls (forpartdepictedinfigure3to8)haveshown300-400pafor1m/sinletvelocityand7kpa-10kpa and30kpa-40kpafor5m/sand10m/srespectivelywhichhasbeenshowninTable1. inlet speed (m/s)average pressure (pa)maximum pressure (pa)wind velocity inside tunnel (m/s)pressure around tunnel walls (pa) 1 300 400 6 350 5 7000 10000 30 8500 10 30000 40000 60 35000
The process mining is essential when it is needed to know what is happening in the execution of the processes, even more when it is manufacturing processes. Also, there is a lack of studies on process mining in manufacturing processes, one reason is because the process mining still a young /uniFB01eld of study. Therefore, this paper presents a bibliometric review of a history of the process mining techniques applied in manufacturing processes. It was used, as methodology, a systematic review of the literature, by con- sulting databases from Web of Science and Scopus, using /uniFB01lters to generate a sample that would match with the scope of the research. As results, it was made some analysis, which presents the identi/uniFB01cation of the years, authors, research source, countries, number of citations, keywords cloud and industry type used in the cases studied. Also, some graphics, tables and information is presented on this paper. Keywords: Process mining, Manufacturing, Review, Bibliometric analysis. /one.pnum Introduction The manufacturing industry has a big role on world economy and development. In manufacturing pro- cesses, as in a production line, it is essential keep the /uniFB02ow running and know what is happening in each sector of the factory. Hence, process mining techniques are needed to get information about what is re- ally happening in the execution of a process, and not what the people think it is happening (van der Aalst et al., /two.pnum/zero.pnum/zero.pnum/four.pnum). Typically these techniques use the log /uniFB01les that collect information about the events detected and stored by the information system in which the process has been performed (Vázquez-Barreiros et al., /two.pnum/zero.pnum/one.pnum/five.pnum). Therefore, this paper aims to present a bibliometric review of a history of the process mining techniques applied in manufacturing processes. The contribution of this study is to show who are the principal authors that work on this area, what are the journals or conferences more likely to this research, what are the principal studies about it, etc. In addition, the information found could show if there are lacks on this kind of research, leading future researchers where are the unexplored areas. This article is structured in /uniFB01ve sections. In section /one.pnum, an introduction; in the section /two.pnum, a theoretical back- ground; in the section /three.pnum the description of the methodology of the samples de/uniFB01nition and the analysis techniques; in the section /four.pnum, the results; and in the section /five.pnum, the /uniFB01nal considerations and suggestion for future researches. Also, the
This paper is a follow-up to two previous papers, one introducing the new bitstream Photon Counting Chirped Amplitude Modulation (AM) Lidar (PC-CAML) with the unipolar Digital Logic Local Oscillator (DLLO) concept, and the other paper introducing the improvement thereof using the bipolar DLLO. In that previous work, there was only a single channel of digital mixing of the DLLO with the received photon counting signal. This paper introduces a new bitstream PC-CAML receiver architecture with an in-phase (I) digital mixing channel and a quadrature phase (Q) digital mixing channel for digital I/Q demodulation with the bipolar DLLO to improve the signal-to-noise ratio (SNR) by 3 dB compared to that for the single digital mixing channel with the bipolar DLLO and by 5.5 dB compared to that for the single digital mixing channel with the unipolar DLLO. (patent pending) The bipolar DLLO with digital I/Q demodulation architecture discussed in this paper retains the key advantages of the previous bitstream PC-CAML with a DLLO systems since it also replaces bulky, power-hungry, and expensive wideband RF analog electronics with digital components that can be implemented in inexpensive silicon complementary metal-oxide-semiconductor (CMOS) read-out integrated circuits (ROICs) to make the bitstream PC-CAML with a DLLO more suitable for compact lidar-on-a-chip systems and lidar array receivers than previous PC- CAML systems. This paper introduces the bipolar DLLO with digital I/Q demodulation receiver architecture for bitstream PC-CAML and presents the initial signal-to-noise ratio (SNR) theory with comparisons to Monte Carlo simulation results. 1. Bipolar DLLO with Digital I/Q Demodulation for Bitstream PC-CAML Concept The patented photon counting chirped amplitude modulation lidar (PC-CAML) concept has been extensively discussed previously. [ref 1-14] In previous PC-CAML systems, the local oscillator (LO) has been a radio-frequency (RF) analog signal applied using expensive, bulky, and power hungry RF analog electronics either in post-detection mixing or via opto-electronic mixing (OEM) at the photon counting detector, including gating of the detector, or applied via pre- detection mixing using an optical intensity modulator. The reader is referred to
/T_h.ligais Preprint introduces polyekthetic processes, a generalization of polytropic processes. /T_h.ligae etymology of the new term is given, and the concept is explained theoretically. A useful associated de/fi.liganition for constant-property processes, for arbitrary properties and expressions thereof, is given, and associated polyekthetic exponents ki j`are de/fi.liganed and a general solution is obtained. Examples on van-der-Waals, general, and ideal gas substances are provided with discussions. Keywords /T_h.ligaermodynamics — Polyekthetic Processes — Polyekthetic Exponent — Bridgman’s Relations — Polytropic Processes Highlights Proposes ‘polyekthetic’ process: a generalization of polytropic processes — Proposes constant-arbitrary property process polyekthetic exponents ki j`— Gives general solution for ki j`— Provides examples and discussions. /one.lfAdjunct Professor. Universidade Tecnol ´ogica Federal do Paran ´a – UTFPR, C ˆampus Guarapuava. Grupo de Pesquisa em Ci ˆencias T ´ermicas. ?Corresponding author : NaaktgeborenC ·PhD@gmail ·com License https://creativecommons.org/licenses/by/4.0/ Contents /one.lf Introduction /one.lf /two.lf Polyekthetic Processes /two.lf /two.lf./one.lf Literature Generalizations of Polytropic Processes /two.lf /two.lf./two.lf Polyekthetic Processes De/fi.liganition . . . . . . . . . . . . /two.lf /two.lf./three.lf Polyekthetic Processes Etymology . . . . . . . . . . . . /three.lf /three.lf General Solution /three.lf /three.lf./one.lf In Partial Di/f_f.ligaerential Notation . . . . . . . . . . . . . /three.lf /three.lf./two.lf In Terms of Bridgman’s Relations . . . . . . . . . . . . /three.lf /three.lf./three.lf Properties of Polyekthetic Exponents . . . . . . . . . /three.lf /four.lf Example Applications /four.lf /four.lf./one.lf Iso- sProcess in const- cv, van-der-Waals Substance /four.lf /four.lf./two.lf General Const-Property Polytropic Processes . . . . /five.lf /five.lf Conclusions /five.lf
The paper deals with the calculation of interstand tensions in continuous rolling mills for flat and long products. A fast calculation method for the interstand tensions from measurable process quantities is a critical point to enable the construction of digital twins for the rolling process, which must be adjusted to the real-world tension behaviour of the production system. It is straightforward to calculate the effects of the tensions on roll forces, torques and the strip or bar velocity. However, the inverse problem of calculating the acting interstand tensions including their effects from the process parameters is of much greater interest but also of a higher complexity, because the interactions between all of the stands in the continuous rolling mill must be taken into account. The paper presents a mathematical model to solve the inverse problem by subsequent linearization of the tensions influences in the rolling mill. Extra nonlinearities are taken into account by modeling the tension-dependent spread by an empirical model. The overall model is solved by an iteration method to yield a fully compatible solution for the constant volume flux as well as the force and torque equilibria in the roll gaps. Results are shown for the tension distributions in strip and rod mills. The results indicate that the present friction conditions and the spreading behaviour of the rolled material have a high impact on the tension distributions. Key words: Interstand Tensions, Wire Rod Rolling, Strip Rolling Contents 1 Introduction 2 2 Method for the inverse calculation of interstand tensions 3 2.1 Calculation of interstand tensions in plane strain flat rolling . . . . . . . . . . . . . . . . . . 3 2.2 Numerical algorithm of the model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.3 Tension calculation with spread . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.4 Effects of interstand tension in round-oval-round pass sequences . . . . . . . . . . . . . . . . 10 3 Results of the model for industrial rolling processes 11 3.1 Finishing train of a hot strip mill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.1.1 Influence of a transfer bar height variation on interstand tensions . . . . . . . . . . . 12 3.1.2 Friction influence on the interstand tension distribution . . . . . . . . . . . . . . . . 13 3.1.3 The influence of the rolling temperature on interstand tensions . . . . . . . . . . . . 13 3.2 Flat bar mill with lateral spread . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.3 Single-strand wire rod mill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4 Discussion 21 5
The paradigm of Cloud production and manufacturing system can be considered as one of the most dominant enablers of Industry 4.0 paradigm. The emphasize of this paradigm for realization of service -oriented production and manufacturing systems has establish ed new perspectives for manufacturing business models toward globalized and distributed orientations. This thesis has proposed the evolution roadmap for realization of Cloud production and manufacturing system concepts. The thesis has proposed a roadmap of evolution which consists of three perspectives. The f irst perspective has contributed to platforms and architectures for globalized service - oriented production and manufacturing systems. The conducted research in this theme contributed for integration and interoperability of stakeholders and processes to enable the fulfillment o f services. The s econd perspective has elaborated the idea of Cloud production and manufacturing systems by encompassing the transportation and logistics as service paradigm. The ma in contributions of the research studies in this theme can be interpreted as mutual and synergic production and transportation service alignment. Moreover, the research studies have contributed to the development of operations research (OR) models for Cloud service network management and planning. The third perspective has extended and contributed to the application of Blockchain and emerging Web 3 technologies in Cloud manufacturing networks. This research studies have accomplished the early steps for improving the effectiveness of the second perspective and have also provided an insight to the perspective of share economy and tokenization models in service -oriented networks. The studies emphasize the potential and capabilities of Web 3 for establishment of new business models in this network. The convergence of the research perspective s concentrates on more realization of service -oriented productio n and supply networks. The globalized interaction frameworks which operate with autonomous structures capable of resembl ing the p