The effect of the load of a combustion engine on energetic and performance parameters of tractor aggregates

The objective of this paper is to demonstrate possibilities how to reduce consumption of Diesel fuel on the one hand and to increase the performance of tractor aggregates on the other. Measurings were performed on a field with clayey-loamy soil, after the harvest of spring barley as forecrop and treatment of soil surface with disc harrowing. At the moment of measuring, the upper soil layer (till 10 cm) contained 16.5 % of humidity. Measured were the following parameters: consumption of Diesel fuel, engine revolutions, total time of ploughing, time of turning, depth of ploughing, and the swath of tractor aggregate. The specific consumption of diesel fuel Qm,1 and the efficiency (performance) of the aggregate W1 were calculated using the aforementioned parameters. The experimental tractor operated always with the full dose of fuel. Measurings were performed within zones A – economic revolutions of the engine (1 580–1 800 min−1) and B – maximum working revolutions of the engine (1 800–2 000 min−1). Basing on measured values it was found out that in zones A and B, the ploughing aggregate Case Magnum MX 285 plus a combined cultivator Köckerling Exaktgrubber – Vario showed 9.1 % of fuel saving. Values of efficiency increased by 11.5%. For the ploughing aggregate Case Magnum MX 285 plus the disc harrow Väderstad Excellent XT 620 the corresponding fuel saving was 17.2 %) while the value of efficiency increased by 7.2 %).

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Degradation of petroleum diesel fuel accelerated by UV irradiation: the impact of ageing on chemical composition and selected physicochemical properties

E3S Web of Conferences ◽

10.1051/e3sconf/201910802003 ◽

2019 ◽

Vol 108 ◽

pp. 02003

Author(s):

Rafał Janus ◽

Karol Kołomański ◽

Mariusz Wądrzyk ◽

Marek Lewandowski

Keyword(s):

Chemical Composition ◽

Uv Irradiation ◽

Diesel Fuel ◽

Physicochemical Parameters ◽

Combustion Engine ◽

Cetane Number ◽

Photochemical Degradation ◽

And Performance ◽

Regular Work ◽

The Impact

The long-term chemical stability of diesel fuel during storage is one of the key factors, which enable the proper operation of the combustion engine and, therefore, may prolong its life. The progressive degradation of particular components of diesel can affect negatively their physicochemical parameters, what, in turn, entails the issues with regular work and performance of the engines and influences adversely the composition of the exhaust. Moreover, the ageing results in the formation of high molecular polymers that form troublesome sediments which cover the bottom of the container and disrupt the injection of the fuel to the combustion chamber. The present study was aimed to investigate the changes in the chemical composition of the conventional petroleum diesel fuel stored with unrestricted air access under UV irradiation (λ = 254 nm). The changes in the chemical composition were determined by means of gas chromatography coupled to mass spectrometry. The changes in the crucial physicochemical parameters, namely: density, viscosity, flash point, cloud point, cetane number, cetane index, and distillation characteristic, caused by the photochemical degradation of diesel components, were discussed with regard to the changes in the molecular composition of diesel.

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Sea Urchins and Circuses: The Modernist Natural Histories of Jean Painlevé and Alexander Calder

Modernist Cultures ◽

10.3366/mod.2018.0205 ◽

2018 ◽

Vol 13 (2) ◽

pp. 187-211

Author(s):

Patricia E. Chu

Keyword(s):

New Media ◽

Sea Urchins ◽

Life Sciences ◽

Three Dimensional ◽

Machine Age ◽

Avant Garde ◽

History Of ◽

And Performance ◽

The One ◽

Natural Historian

The Paris avant-garde milieu from which both Cirque Calder/Calder's Circus and Painlevé’s early films emerged was a cultural intersection of art and the twentieth-century life sciences. In turning to the style of current scientific journals, the Paris surrealists can be understood as engaging the (life) sciences not simply as a provider of normative categories of materiality to be dismissed, but as a companion in apprehending the “reality” of a world beneath the surface just as real as the one visible to the naked eye. I will focus in this essay on two modernist practices in new media in the context of the history of the life sciences: Jean Painlevé’s (1902–1989) science films and Alexander Calder's (1898–1976) work in three-dimensional moving art and performance—the Circus. In analyzing Painlevé’s work, I discuss it as exemplary of a moment when life sciences and avant-garde technical methods and philosophies created each other rather than being classified as separate categories of epistemological work. In moving from Painlevé’s films to Alexander Calder's Circus, Painlevé’s cinematography remains at the forefront; I use his film of one of Calder's performances of the Circus, a collaboration the men had taken two decades to complete. Painlevé’s depiction allows us to see the elements of Calder's work that mark it as akin to Painlevé’s own interest in a modern experimental organicism as central to the so-called machine-age. Calder's work can be understood as similarly developing an avant-garde practice along the line between the bestiary of the natural historian and the bestiary of the modern life scientist.

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The Munich conference of Minister-Presidents of German lands in 1947

OOO Zhurnal Voprosy Istorii ◽

10.31166/voprosyistorii202010statyi28 ◽

2020 ◽

Vol 2020 (10-2) ◽

pp. 86-98

Author(s):

Ivan Popov

Keyword(s):

The State ◽

State Governments ◽

The West ◽

Constitutional Development ◽

The Moment ◽

The One

The paper deals with the organization and decisions of the conference of the Minister-Presidents of German lands in Munich on June 6-7, 1947, which became the one and only meeting of the heads of the state governments of the western and eastern occupation zones before the division of Germany. The conference was the first experience of national positioning of the regional elite and clearly demonstrated that by the middle of 1947, not only between the allies, but also among German politicians, the incompatibility of perspectives of further constitutional development was existent and all the basic conditions for the division of Germany became ripe. Munich was the last significant demonstration of this disunity and the moment of the final turn towards the three-zone orientation of the West German elite.

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Coal Fly Ash and Polyacrylamide Influence Transport and Redistribution of Soil Nitrogen in a Sandy Sloping Land

Agriculture ◽

10.3390/agriculture11010047 ◽

2021 ◽

Vol 11 (1) ◽

pp. 47

Author(s):

Kai Yang ◽

Zejun Tang ◽

Jianzhang Feng

Keyword(s):

Fly Ash ◽

Sandy Soil ◽

Coal Fly Ash ◽

Soil Layer ◽

Nutrient Retention ◽

Soil Surface ◽

Rainfall Event ◽

N Losses ◽

N Concentration ◽

Application Rates

Sandy soils are prone to nutrient losses, and consequently do not have as much as agricultural productivity as other soils. In this study, coal fly ash (CFA) and anionic polyacrylamide (PAM) granules were used as a sandy soil amendment. The two additives were incorporated to the sandy soil layer (depth of 0.2 m, slope gradient of 10°) at three CFA dosages and two PAM dosages. Urea was applied uniformly onto the low-nitrogen (N) soil surface prior to the simulated rainfall experiment (rainfall intensity of 1.5 mm/min). The results showed that compared with no addition of CFA and PAM, the addition of CFA and/or PAM caused some increases in the cumulative NO3−-N and NH4+-N losses with surface runoff; when the rainfall event ended, 15% CFA alone treatment and 0.01–0.02% PAM alone treatment resulted in small but significant increases in the cumulative runoff-associated NO3−-N concentration (p < 0.05), meanwhile 10% CFA + 0.01% PAM treatment and 15% CFA alone treatment resulted in nonsignificant small increases in the cumulative runoff-associated NH4+-N concentration (p > 0.05). After the rainfall event, both CFA and PAM alone treatments increased the concentrations of NO3−-N and NH4+-N retained in the sandy soil layer compared with the unamended soil. As the CFA and PAM co-application rates increased, the additive effect of CFA and PAM on improving the nutrient retention of sandy soil increased.

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Deep Learning Approach for Vibration Signals Applications

Sensors ◽

10.3390/s21113929 ◽

2021 ◽

Vol 21 (11) ◽

pp. 3929

Author(s):

Han-Yun Chen ◽

Ching-Hung Lee

Keyword(s):

Surface Roughness ◽

Tool Wear ◽

Parameters Optimization ◽

Frequency Spectra ◽

Vibration Signals ◽

Bearing Faults ◽

Time Frequency ◽

And Performance ◽

The One ◽

Short Time

This study discusses convolutional neural networks (CNNs) for vibration signals analysis, including applications in machining surface roughness estimation, bearing faults diagnosis, and tool wear detection. The one-dimensional CNNs (1DCNN) and two-dimensional CNNs (2DCNN) are applied for regression and classification applications using different types of inputs, e.g., raw signals, and time-frequency spectra images by short time Fourier transform. In the application of regression and the estimation of machining surface roughness, the 1DCNN is utilized and the corresponding CNN structure (hyper parameters) optimization is proposed by using uniform experimental design (UED), neural network, multiple regression, and particle swarm optimization. It demonstrates the effectiveness of the proposed approach to obtain a structure with better performance. In applications of classification, bearing faults and tool wear classification are carried out by vibration signals analysis and CNN. Finally, the experimental results are shown to demonstrate the effectiveness and performance of our approach.

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On Performance of Sparse Fast Fourier Transform Algorithms Using the Aliasing Filter

Electronics ◽

10.3390/electronics10091117 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1117

Author(s):

Bin Li ◽

Zhikang Jiang ◽

Jie Chen

Keyword(s):

Fourier Transform ◽

Fast Fourier Transform ◽

High Efficiency ◽

Theory And Practice ◽

Long Time ◽

And Performance ◽

Binary Tree Search ◽

The One ◽

Sparse Fast Fourier Transform ◽

L1 And L2

Computing the sparse fast Fourier transform (sFFT) has emerged as a critical topic for a long time because of its high efficiency and wide practicability. More than twenty different sFFT algorithms compute discrete Fourier transform (DFT) by their unique methods so far. In order to use them properly, the urgent topic of great concern is how to analyze and evaluate the performance of these algorithms in theory and practice. This paper mainly discusses the technology and performance of sFFT algorithms using the aliasing filter. In the first part, the paper introduces the three frameworks: the one-shot framework based on the compressed sensing (CS) solver, the peeling framework based on the bipartite graph and the iterative framework based on the binary tree search. Then, we obtain the conclusion of the performance of six corresponding algorithms: the sFFT-DT1.0, sFFT-DT2.0, sFFT-DT3.0, FFAST, R-FFAST, and DSFFT algorithms in theory. In the second part, we make two categories of experiments for computing the signals of different SNRs, different lengths, and different sparsities by a standard testing platform and record the run time, the percentage of the signal sampled, and the L0, L1, and L2 errors both in the exactly sparse case and the general sparse case. The results of these performance analyses are our guide to optimize these algorithms and use them selectively.

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Epidemiological surveillance and performance assessment: the two roles of health indicators during the COVID-19 pandemic

International Journal of Law in Context ◽

10.1017/s1744552321000276 ◽

2021 ◽

Vol 17 (2) ◽

pp. 186-203

Author(s):

Nathan Genicot

Keyword(s):

Public Health ◽

Performance Assessment ◽

Health Indicators ◽

Health Policies ◽

Epidemiological Surveillance ◽

Public Health Policies ◽

History Of ◽

And Performance ◽

The One ◽

Massive Development

AbstractThe COVID-19 pandemic has given rise to the massive development and use of health indicators. Drawing on the history of international public health and of the management of infectious disease, this paper attempts to show that the normative power acquired by metrics during the pandemic can be understood in light of two rationales: epidemiological surveillance and performance assessment. On the one hand, indicators are established to evaluate and rank countries’ responses to the outbreak; on the other, the evolution of indicators has a direct influence on the content of public health policies. Although quantitative data are an absolute necessity for coping with such disasters, it is critical to bear in mind the inherent partiality and precarity of the information provided by health indicators. Given the growing importance of normative quantitative devices during the pandemic, and assuming that their influence is unlikely to decrease in the future, they call for close scrutiny.

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Experimental investigations on diesel engine using alumina nanoparticle fuel additive

Advances in Mechanical Engineering ◽

10.1177/1687814020988402 ◽

2021 ◽

Vol 13 (2) ◽

pp. 168781402098840

Author(s):

Mohammed S Gad ◽

Sayed M Abdel Razek ◽

PV Manu ◽

Simon Jayaraj

Keyword(s):

Diesel Engine ◽

Diesel Fuel ◽

Alumina Nanoparticles ◽

Experimental Investigations ◽

Fuel Additive ◽

Alumina Nanoparticle ◽

Fuel Injectors ◽

Performance And Emission ◽

And Performance ◽

The Impact

Experimental work was done to examine the impact of diesel fuel with alumina nanoparticles on combustion characteristics, emissions and performance of diesel engine. Alumina nanoparticles were mixed with crude diesel in various weight fractions of 20, 30, and 40 mg/L. The engine tests showed that nano alumina addition of 40 ppm to pure diesel led to thermal efficiency enhancement up to 5.5% related to the pure diesel fuel. The average specific fuel consumption decrease about neat diesel fuel was found to be 3.5%, 4.5%, and 5.5% at dosing levels of 20, 30, and 40 ppm, respectively at full load. Emissions of smoke, HC, CO, and NOX were found to get diminished by about 17%, 25%, 30%, and 33%, respectively with 40 ppm nano-additive about diesel operation. The smaller size of nanoparticles produce fuel stability enhancement and prevents the fuel atomization problems and the clogging in fuel injectors. The increase of alumina nanoparticle percentage in diesel fuel produced the increases in cylinder pressure, cylinder temperature, heat release rate but the decreases in ignition delay and combustion duration were shown. The concentration of 40 ppm alumina nanoparticle is recommended for achieving the optimum improvements in the engine’s combustion, performance and emission characteristics.

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Helium, [Fe/H] Abundances and the HR (Log TEFF, MBol) Diagram With Hipparcos Data of The Four Nearest Open Clusters: Hyades, Coma Berenices, The Pleiades and Praesepe

Highlights of Astronomy ◽

10.1017/s1539299600022206 ◽

1998 ◽

Vol 11 (1) ◽

pp. 565-565

Author(s):

G. Cayrel de Strobel ◽

R. Cayrel ◽

Y. Lebreton

Keyword(s):

Main Sequence ◽

Open Clusters ◽

Main Sequence Stars ◽

Spectroscopic Analyses ◽

Solar Metallicity ◽

Metal Abundances ◽

The Mean ◽

The Moment ◽

The One ◽

Best Fit

After having studied in great detail the observational HR diagram (log Teff, Mbol) composed by 40 main sequence stars of the Hyades (Perryman et al.,1997, A&A., in press), we have tried to apply the same method to the observational main sequences of the three next nearest open clusters: Coma Berenices, the Pleiades, and Praesepe. This method consists in comparing the observational main sequence of the clusters with a grid of theoretical ZAMSs. The stars composing the observational main sequences had to have reliable absolute bolometric magnitudes, coming all from individual Hipparcos parallaxes, precise bolometric corrections, effective temperatures and metal abundances from high resolution detailed spectroscopic analyses. If we assume, following the work by Fernandez et al. (1996, A&A,311,127), that the mixing-lenth parameter is solar, the position of a theoretical ZAMS, in the (log Teff, Mbol) plane, computed with given input physics, only depends on two free parameters: the He content Y by mass, and the metallicity Z by mass. If effective temperature and metallicity of the constituting stars of the 4 clusters are previously known by means of detailed analyses, one can deduce their helium abundances by means of an appropriate grid of theoretical ZAMS’s. The comparison between the empirical (log Teff, Mbol) main sequence of the Hyades and the computed ZAMS corresponding to the observed metallicity Z of the Hyades (Z= 0.0240 ± 0.0085) gives a He abundance for the Hyades, Y= 0.26 ± 0.02. Our interpretation, concerning the observational position of the main sequence of the three nearest clusters after the Hyades, is still under way and appears to be greatly more difficult than for the Hyades. For the moment we can say that: ‒ The 15 dwarfs analysed in detailed in Coma have a solar metallicity: [Fe/H] = -0.05 ± 0.06. However, their observational main sequence fit better with the Hyades ZAMS. ‒ The mean metallicity of 13 Pleiades dwarfs analysed in detail is solar. A metal deficient and He normal ZAMS would fit better. But, a warning for absorption in the Pleiades has to be recalled. ‒ The upper main sequence of Praesepe, (the more distant cluster: 180 pc) composed by 11 stars, analysed in detail, is the one which has the best fit with the Hyades ZAMS. The deduced ‘turnoff age’ of the cluster is slightly higher than that of the Hyades: 0.8 Gyr instead of 0.63 Gyr.

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