THE EFFECT OF THE WEAR DEGREE OF WORKING ELEMENTS IN A JAW CRUSHER ON THE OPERATING EFFECTIVENESS OF A TWO-STAGE GRANITE GRINDING SYSTEM

Tribologia ◽  
2021 ◽  
Vol 295 (1) ◽  
pp. 7-14
Author(s):  
Mateusz Dziubek ◽  
Dominika Grygier
Keyword(s):  
Grain Size ◽  
Service Life ◽  
Quality Indicator ◽  
Two Stage ◽  
Crushed Material ◽  
Jaw Crusher ◽  
Mean Grain Size ◽  
Two Stages ◽  
Grinding System

The article presents an analysis of the influence of the wear degree of working elements in a jaw crusher on the crushing process and on the quality of the crushed material. The evaluation of the operating effectiveness of a technological system comprising two crushers was based on the quality indicator of the crushed product, i.e. on the share of irregular grains for a fraction with a mean grain size of 31.5/63 mm at each of the two stages of crushing. The wear degree was monitored by performing microscopic observations of the plates in the fixed jaw and by measuring the critical geometric characteristics of the crusher, e.g., tooth height, jaw size, and discharge opening size, during the entire service life of the crusher.

A novel two-stage method of plant seedlings classification based on deep learning

2021 ◽  
pp. 1-11
Author(s):  
Tianhong Dai ◽  
Shijie Cong ◽  
Jianping Huang ◽  
Yanwen Zhang ◽  
Xinwang Huang ◽  
...  
Keyword(s):  
Deep Learning ◽  
Learning Technology ◽  
Two Stage ◽  
Second Stage ◽  
Stage Classification ◽  
Different Types ◽  
Two Stages ◽  
Plant Seedlings

In agricultural production, weed removal is an important part of crop cultivation, but inevitably, other plants compete with crops for nutrients. Only by identifying and removing weeds can the quality of the harvest be guaranteed. Therefore, the distinction between weeds and crops is particularly important. Recently, deep learning technology has also been applied to the field of botany, and achieved good results. Convolutional neural networks are widely used in deep learning because of their excellent classification effects. The purpose of this article is to find a new method of plant seedling classification. This method includes two stages: image segmentation and image classification. The first stage is to use the improved U-Net to segment the dataset, and the second stage is to use six classification networks to classify the seedlings of the segmented dataset. The dataset used for the experiment contained 12 different types of plants, namely, 3 crops and 9 weeds. The model was evaluated by the multi-class statistical analysis of accuracy, recall, precision, and F1-score. The results show that the two-stage classification method combining the improved U-Net segmentation network and the classification network was more conducive to the classification of plant seedlings, and the classification accuracy reaches 97.7%.

Management of quality and competitiveness of products

2020 ◽  
pp. 65-78
Author(s):  
Kh.A. Faskhiev
Keyword(s):  
Quality Indicator ◽  
Quantitative Assessment ◽  
Stage Model ◽  
Passenger Cars ◽  
Two Stage ◽  
Qualitative And Quantitative ◽  
Management Quality ◽  
Quality Of Products

A method is proposed for a sequential quantitative assessment of the quality of products, based on their aggregatedecomposition analysis, combining qualitative and quantitative analyzes of the quality of objects, the indicators of which can be hierarchically structured. A two-stage model for managing the level of quality and product competitiveness has been developed. The implementation of this methodology is shown on the example of assessing truck cranes and summer tyres of passenger cars. Keywords assessment, management, quality, competitiveness, quality indicator, product, weightage, truck crane, summer tyre. faskhiev@mail. ru

OS CAMINHOS DAS ÁGUAS NO MUNICÍPIO DE CARIRÉ, CEARÁ, BRASIL

2019 ◽  
Vol 21 (2) ◽  
pp. 564-580
Author(s):  
Eloiza Rocha Queiroz ◽  
José Falcão Sobrinho
Keyword(s):  
Water Resources ◽  
Potable Water ◽  
Field Trips ◽  
Central Theme ◽  
Northeast Region ◽  
Brazilian Semiarid ◽  
Long Time ◽  
Short Rains ◽  
Two Stages

A região Nordeste do Brasil vem sendo alvo de medidas do Estado a mais de um século, na tentativa de solucionar o problema da falta de água em época de secas. O Estado do Ceará, por sua vez, apresenta boa parte de seu território inserido no semiárido brasileiro, uma região caracterizada pelo clima seco, com poucas chuvas e elevada evapotranspiração. A problemática da água existe há bastante tempo, principalmente o acesso em quantidade e qualidade suficientes para atender a população. O presente trabalho tem como tema central a questão dos recursos hídricos, com enfoque no abastecimento humano do município de Cariré, localizado na região noroeste do Ceará. Nosso objetivo consiste em apresentar um panorama de como atualmente a população carireense tem acesso à água potável. A metodologia adotada constitui-se em duas etapas: na primeira, realizamos levantamento de material bibliográfico e a segunda diz respeito a parte prática realizada em saídas a campo. Segundo a ONU, a água é um bem comum e que deve ser de acesso a todos, é um direito humano. Nesta perspectiva, o gerenciamento adequado dos recursos hídricos é essencial para a manutenção da qualidade de vida. Palavras-chave: Recursos Hídricos; Abastecimento Humano; Cariré-Ce. ABSTRACTThe pnortheast region from Brazil has been subject of measures for more than a century in attempts to solve the problems lack of water in dry season. The state of Ceará has a good part of its territorial inserted in Brazilian semiarid, a region characterized by dry climate, short rains and high evapotranspiration. The water issue has existed for a long time, mainly in a sufficient access of quantity and quality to serve the population. Then, this article has as a central theme the water resources focusing on water supply of the Cariré localized at Northeast region from Ceará. Therefore the purpose of the paper is to present a study about how the Carire’s population has had access to potable water currently. The methodology adopted to this research consists of two stages: Firstly it was carried out a survey of bibliographical material and secondly it concerned the practical part carried out in the field trips. In accordance to United nations, water is a commom good and it has to be available to everyone, it is a human rights. In that sense, the proper management of water resources is essential to keep the quality of life.Key-words: Human supply; Water resources; Cariré – Ce. RÉSUMÉLa région du nord-est du Brésil est la cible de mesures prises par l’État depuis plus d’un siècle pour tenter de résoudre le problème de la pénurie d’eau en saison sèche. L’État du Ceará, en revanche, présente une bonne partie de son territoire inséré dans le semi-aride brésilien, région caractérisée par un climat sec, avec peu de pluies et une forte évapotranspiration. Le problème de l'eau existe depuis longtemps, principalement l'accès en quantité et qualité suffisantes pour satisfaire la population. Le travail actuel a pour thème central la question des ressources en eau, en mettant l'accent sur l'approvisionnement humain de la municipalité de Cariré, située dans la région nord-ouest du Ceará. Notre objectif est de présenter un aperçu de la façon dont la population carioca a actuellement accès à l’eau potable. La méthodologie adoptée comporte deux étapes: dans le premier, nous procédons à une enquête sur le matériel bibliographique et le second à la partie pratique réalisée lors des visites sur le terrain. Selon l'ONU, l'eau est un bien commun et doit être accessible à tous, c'est un droit humain. Dans cette perspective, la gestion adéquate des ressources en eau est essentielle au maintien de la qualité de la vie.Mots-clés: Ressources en eau; Approvisionnement humain; Cariré-Ce.

Sedimentological and Biological Changes Associated with the Construction of the Oil Terminal of Antifer, France

1984 ◽  
Vol 16 (3-4) ◽  
pp. 399-406
Author(s):  
Y Monbet
Keyword(s):  
Grain Size ◽  
Environmental Changes ◽  
Biological Effects ◽  
Standing Stock ◽  
Natural Populations ◽  
Benthic Fauna ◽  
Field Investigations ◽  
Mean Grain Size ◽  
To Receive ◽  
Principal Species

A study was conducted to gain insight on actual sedimentological and biological effects associated with the construction of an oil Terminal designed to receive 500 000 d.w.t. tankers. Field investigations and subsequent laboratory analyses were organized to evaluate the nature and magnitude of environmental changes on benthic macrofauna, three years after the end of the construction. Sediments were found to decrease dramatically in medium grain size in area sheltered by the newly built breakwater. Increase of percentage of silt and clays (90 % against 20 %) was observed leeward of the jetty. The benthic fauna showed significant modifications. Although the same community (Pectinaria kareni Abra alba) recolonized the bottom after the dredging of up to 30 × 106 m3 of sediments, increase in abundance occured. Biomass remained at a constant level and decrease of diversity was observed. Considering the rate of siltation, and assuming a constant siltation rate equal to the rate observed from 1975 to 1978, a simple regressive model relating biomass to mean grain size of sediments has been developped. This model allowed the prediction of biomass and production of the two principal species for the period 1978 – 1981. Continuous siltation within the harbor leads to a maximum of biomass from years after the end of the construction, followed by a decrease of standing stock. This process may be explained by the respective tolerance of the two principal species to increase silt contant and also probably by the accumulation of organic matter which may impede the development of natural populations.

MULTISTAGE MICROSTRIP UHF LOAD

2018 ◽  
pp. 53-57 ◽  
Author(s):  
G. G. Savenkov ◽  
V. P. Razinkin ◽  
A. D. Mekhtiev
Keyword(s):  
Frequency Response ◽  
Frequency Band ◽  
High Power ◽  
Two Stage ◽  
High Power Microwave ◽  
Modelling Method ◽  
Optimal Values ◽  
Inductive Elements ◽  
Power Microwave

Applications of modern terminal loads and its relevant disadvantages are described in this paper. The decomposing method of wideband microwave high power microstrip loads design is proposed in this paper with purpose of matching quality improving. Multiple extension of multistage load bandwidth is provided by using of external matching circuit and internal matching inductive elements. The maximum reachable bandwidth of multistage load is estimated and optimal values of mathing circuit elements are founded on basis of equivalent lumped scheme. The topology of microstrip two-stage high power microwave load is developed and its frequency response, calculated via numeric electrodynamic modelling method is outlined in the paper. Modelling results show good matching quality of considered load at the frequency band below 3,5 GHz.

scholarly journals A Comparison of Two-Stage and Traditional Co-Composting of Green Waste and Food Waste Amended with Phosphate Rock and Sawdust

2021 ◽  
Vol 13 (3) ◽  
pp. 1109
Author(s):  
Edgar Ricardo Oviedo-Ocaña ◽  
Angélica María Hernández-Gómez ◽  
Marcos Ríos ◽  
Anauribeth Portela ◽  
Viviana Sánchez-Torres ◽  
...  
Keyword(s):  
Organic Matter ◽  
Product Quality ◽  
Food Waste ◽  
Phosphate Rock ◽  
Pilot Scale ◽  
Two Stage ◽  
Green Waste ◽  
Wet Weight ◽  
Two Phases

The composting of green waste (GW) proceeds slowly due to the presence of slowly degradable compounds in that substrate. The introduction of amendments and bulking materials can improve organic matter degradation and end-product quality. However, additional strategies such as two-stage composting, can deal with the slow degradation of green waste. This paper evaluates the effect of two-stage composting on the process and end-product quality of the co-composting of green waste and food waste amended with sawdust and phosphate rock. A pilot-scale study was developed using two treatments (in triplicate each), one being a two-stage composting and the other being a traditional composting. The two treatments used the same mixture (wet weight): 46% green waste, 19% unprocessed food waste, 18% processed food waste, 13% sawdust, and 4% phosphate rock. The traditional composting observed a higher degradation rate of organic matter during the mesophilic and thermophilic phases and observed thermophilic temperatures were maintained for longer periods during these two phases compared to two-stage composting (i.e., six days). Nonetheless, during the cooling and maturation phases, the two treatments had similar behaviors with regard to temperature, pH, and electrical conductivity, and the end-products resulting from both treatments did not statistically differ. Therefore, from this study, it is concluded that other additional complementary strategies must be evaluated to further improve GW composting.

Evaluation of Drying Performance, Energy Consumption, and Quality of Two-Stage Dried Maize Grain

2021 ◽  
Author(s):  
Md. Akhtaruzzaman ◽  
Md. Hasan Tarek Mondal ◽  
Mrityunjoy Biswas ◽  
Md. Abdul Momin Sheikh ◽  
Anwara Akter Khatun ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Two Stage ◽  
Maize Grain

scholarly journals Modernization of two-stage main fans at the end of the service life

2021 ◽  
Vol 773 (1) ◽  
pp. 012047
Author(s):  
AM Krasyuk ◽  
IV Lugin ◽  
PV Kosykh
Keyword(s):  
Service Life ◽  
Two Stage

scholarly journals Preparation of high-entropy carbides by different sintering techniques

2021 ◽  
Vol 56 (19) ◽  
pp. 11237-11247 ◽  
Author(s):  
Johannes Pötschke ◽  
Manisha Dahal ◽  
Mathias Herrmann ◽  
Anne Vornberger ◽  
Björn Matthey ◽  
...  
Keyword(s):  
Grain Size ◽  
Single Phase ◽  
X Ray Diffraction ◽  
Vacuum Sintering ◽  
X Ray ◽  
High Entropy ◽  
Mean Grain Size ◽  
The Mean ◽  
Gas Pressure Sintering ◽  
Hardness Values

AbstractDense (Hf, Ta, Nb, Ti, V)C- and (Ta, Nb, Ti, V, W)C-based high-entropy carbides (HEC) were produced by three different sintering techniques: gas pressure sintering/sinter–HIP at 1900 °C and 100 bar Ar, vacuum sintering at 2250 °C and 0.001 bar as well as SPS/FAST at 2000 °C and 60 MPa pressure. The relative density varied from 97.9 to 100%, with SPS producing 100% dense samples with both compositions. Grain size measurements showed that the substitution of Hf with W leads to an increase in the mean grain size of 5–10 times the size of the (Hf, Ta, Nb, Ti, V,)C samples. Vacuum-sintered samples showed uniform grain size distribution regardless of composition. EDS mapping revealed the formation of a solid solution with no intermetallic phases or element clustering. X-ray diffraction analysis showed the structure of mostly single-phase cubic high-entropy carbides. Hardness measurements revealed that (Hf, Ta, Nb, Ti, V)C samples possess higher hardness values than (Ta, Nb, Ti, V, W)C samples.

scholarly journals X-ray diffraction analysis of kaolin M1 and M2 via the Williamson–Hall and Warren–Averbach methods

2021 ◽  
pp. 174751982098472
Author(s):  
Lalmi Khier ◽  
Lakel Abdelghani ◽  
Belahssen Okba ◽  
Djamel Maouche ◽  
Lakel Said
Keyword(s):  
Grain Size ◽  
High Temperature ◽  
Low Temperature ◽  
Diffraction Analysis ◽  
Mechanical Resistance ◽  
X Ray Diffraction ◽  
Integral Breadth ◽  
X Ray ◽  
Mullite Phase

Kaolin M1 and M2 studied by X-ray diffraction focus on the mullite phase, which is the main phase present in both products. The Williamson–Hall and Warren–Averbach methods for determining the crystallite size and microstrains of integral breadth β are calculated by the FullProf program. The integral breadth ( β) is a mixture resulting from the microstrains and size effect, so this should be taken into account during the calculation. The Williamson–Hall chart determines whether the sample is affected by grain size or microstrain. It appears very clearly that the principal phase of the various sintered kaolins, mullite, is free from internal microstrains. It is the case of the mixtures fritted at low temperature (1200 °C) during 1 h and also the case of the mixtures of the type chamotte cooks with 1350 °C during very long times (several weeks). This result is very significant as it gives an element of explanation to a very significant quality of mullite: its mechanical resistance during uses at high temperature remains.

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