scholarly journals Evaluation of the Quality of Conical Picks and the Possibility of Predicting the Costs of Their Use

2020 ◽  
Vol 3 (1) ◽  
pp. 491-504
Author(s):  
Krzysztof Krauze ◽  
Kamil Mucha ◽  
Tomasz Wydro

AbstractCurrently, the user’s choice of a conical pick involves specifying its geometric and material parameters, taking into account the place and conditions of its work. The selection is then made, usually on the basis of solely one criterion, which is the price. Thus, at the stage of both purchase and operation, the quality of picks and their suitability for a specific machine and the processed mineral are not assessed. Therefore, a method was developed to enable conducting tests that determine the geometric parameters of a pick, the types of materials of the pick body and WC insert as well as the pick wear rate (intensity) in a laboratory workstation. The wear rate (intensity) is described by the C2 index – the smaller is its value, the slower is the pick’s wear. The C2 index has been used to forecast the wear of picks and to determine their unit price and operating costs. This allows for precise determination of investment requirements and a proper selection of the pick.

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3696
Author(s):  
Krzysztof Krauze ◽  
Kamil Mucha ◽  
Tomasz Wydro ◽  
Edward Pieczora

User’s choices of conical picks currently involve specifying their material and geometric parameters (functional requirements), incorporating the place and conditions of their work (operational requirements). The selection is usually made based on solely one criterion, which is the price. Thus, at the stage of both purchase and operation, the quality of picks, as well as their matching for a specific machine, are not assessed. The problem of defining whether the producer has fulfilled the user’s requirements arises only when the user questions the picks’ quality. Analysis of this problem has resulted in developing assumptions, concepts and research procedures based on the cutting process requirements. The procedure allows conducting tests to determine the geometric parameters of a pick, the type of material of the pick body and WC-Co insert, as well as the pick wear rate (intensity). The C2 index describes the wear rate (intensity)—the smaller its value, the slower the pick’s wear. Laboratory tests were carried out at the AGH University of Science and Technology in Kraków, Poland. Following the developed method and procedure, the quality of picks was precisely and unambiguously assessed. The C2 index, apart from testing the quality of picks, was also used to forecast their wear. Based on the C2 index, a method is proposed to estimate the wear rate of conical picks provided by different manufacturers and determine the acceptable unit price and operating costs. Thus, it is possible and reasonable to precisely define the investment requirements and appropriately select the pick. Relevant tests were carried out for eight different types of conical picks used in roadheaders, longwall shearers and shaft-boring roadheaders.


2020 ◽  
Vol 23 (9) ◽  
pp. 77-85
Author(s):  
Nataliia Kyrnis

Modernization of the Ukrainian economy under the influence of global post-industrial trends mainstreams the priority of development of science-intensive, high-tech, innovative activities. Modernization creates the preconditions for strengthening competitive positions in the national and global markets. In modern conditions, the issue of assessing the competitiveness of catering companies is relevant. High competitiveness of the enterprise is the main condition of its activity and development. The purpose of the study is to assess the competitiveness of catering companies in the market of catering services in Ukraine. The study proposes methodological approaches to assessing the competitiveness of catering companies. Methodological approaches include continuity of monitoring, determination of parameters, indicators and criteria, selection of optimal evaluation methods. In the process of research the following methods were used: sociological survey, simple ranking, integrated assessment and factor method, system approach method. It was established that methodical approaches to assessing the competitiveness of catering companies include justification and development of a system of socio-economic indicators and criteria (product quality, quality of service, quality and organizational staff, efficiency, efficiency of personnel management, price). Methodological approaches include a set of indicators that form an integrated indicator of competitiveness. This indicator allows to consider objective differences in the dynamics of enterprises, the conditions of use of available resources in the process of forecasting and development of enterprises. A comprehensive diagnosis was carried out based on an integrated indicator of the competitiveness of restaurants on special orders (catering), during which it was determined that its level has a significant differentiation according to the indicators of the studied enterprises, which are due to both external and internal factors, which allows the development of strategic priorities and specific measures to develop the image of the enterprise and increase its competitiveness.


Author(s):  
SILA MARY RODRIGUES FERREIRA ◽  
PATRÍCIA V. DE OLIVEIRA ◽  
DANIELA PRETTO

Devido à ausência de metodologia para avaliação da qualidade do pão francês em Sistema de Alimentação Coletiva, o presente trabalho teve como objetivo avaliar os parâmetros físicos, físico-químicos e sensoriais do pão francês, comercializado em cinco panificadoras de Curitiba. Nas análises físicas, em cinco repetições, as amostras foram submetidas à determinação do peso, volume, volume específico, densidade e peso seco. As análises físicoquímicas foram realizadas em triplicata de acordo com procedimento da Association of Official Analytical Chemists (AOAC). Para avaliar a qualidade do pão foi utilizada a metodologia do sistema de pontuação global, mediante análise sensorial dos seguintes atributos: cor da crosta, forma e simetria, características da crosta, aspecto da pestana, aspecto de quebra da crosta, cor do miolo, porosidade, textura, aroma e sabor. Atribuiu-se pontuação (de 0 a 5) para cada variável, a qual foi multiplicada pelo fator que expressa a importância relativa de cada variável (totalizando 100 pontos), obtendo-se a classificação dos produtos pela soma dos pontos. Os resultados dos testes físicos e físicoquímicos das cinco amostras de pão francês apresentaram média de 52,23 g de peso, 31,98% de umidade, 68,02% de extrato seco, 35,49 g de peso seco, 371,8 cm3 de volume, 7,23 cm3/g de volume específico e 0,15 g/cm3 de densidade. As amostras XA, XB e XC apresentaram os melhores resultados podendo ser consideradas como as melhores. Na classificação pelo sistema de pontuação global, as amostras apresentaram diferença em nível de 1% de significância em relação à qualidade. As amostras XA e XB apresentaram boa qualidade, seguidas pelas amostras XC e XE (regular), sendo a amostra XD classificada como ruim. Os resultados obtidos permitem sugerir a adoção desta metodologia de avaliação para seleção de pão francês, em Sistema de Alimentação Coletiva. QUALITY PATTERNS OF FRENCH BREAD Abstract Due to the absence of a methodology to evaluate the quality of French bread in a Production of Collective Meals System, the present work had as objective to evaluate the quality, physical, physical-chemical and sensorial parameters of the French bread marketed in five bakeries in Curitiba (Brazil). In the physical analyses, with five repetitions, the samples were submitted to the determination of weight, volume, specific volume, density and dry weight. The physical-chemical analysis was accomplished with three replicates in agreement with the AOAC procedure. To evaluate the quality of the bread, the methodology of global punctuation system was used, by sensorial analysis of the following attributes: color of the crust, form and symmetry, characteristics of the crust, aspect of the lash, aspect of crust break, color of the crumb, porosity, texture, aroma and flavor. For each variable a grade (from 0 to 5) was attributed, which was multiplied by a factor that expressed the relative importance of each variable (to a total of 100 points), obtaining the product classification by the sum of the points. The results of the physical and physical-chemical tests of the five samples of French bread presented an average of 52,23 g of weight; 31,98% of humidity, 68,02% of dry extract, 35,49 g of dry weight, 371,8 cm3 of volume, 7,23 cm3/g of specific volume and 0,15 g/cm3 of density. The samples XA, XB and XC presented better results and could be considered as the best. In the classification using the global punctuation system, the samples presented difference at the level of 1% of significance in relation to the quality. The samples XA and XB presented good quality, followed by the samples XC and XE (regular), being the sample XD classified as bad. The results obtained allow suggest the evaluation methodology for selection of French bread in a Production of Collective Meals System.


Author(s):  
Kazimiera Juszka

The aim of the article is to present the protection of human rights in inspection in cases of killings. Analisys will be presented by aspects, which have been created by forensic tactics and forensic technique. Presentation of titular institution will covered the effects of carrying out the action on the dection process of the perpetrators of killings. The title factors in the protection of human rights in the conduct of investigations of killing cases include the essence of the inspection, rules for conducting the inspection, qualitative and quantitative selection of the inspection group, izolation of the inspection site, inspection stages, guide with a tracking dog, rules of inspection documentation, technical and process securing of the subject of inspection, post-inspection note, supplementary inspection, repeated inspection, continuation of the case. The factor of human rights protection in this article is understood as any activity of the organs of criminal proccedings related to the inspection of the scene of crime, aimed at respecting human rights. The measure of observance of human rights is the determination of a certain sequence of activities in the detection process, which is then followed during the implementation of this process, as well as the determination of the maximum quality of these activities, the intensity and content of the information stream stimulating the detection process as a whole, as well as individual segments or stages.


2020 ◽  
Vol 164 ◽  
pp. 09039
Author(s):  
Rima Petrosyan ◽  
Alexander Mailyan

The choice of the optimal option for the production of in the construction of buildings and structures is based on a preliminary generalization and analysis of the most promising options for the implementation of construction and installation from which the most rational optimal in the is selected conditions under consideration. The purpose of the study is to determine the optimal option for production of at the convex cost function. We used the method of the determination of costs on the duration of works, represented by a convex function showing the shorter the duration of the project the more costs are required when it is reduced by the same amount. The key parameters affecting the final result of construction are the duration cost and quality of performed. Consequently, one of the main tasks is to draw up a works schedule with close coordination of the resources necessary for their implementation. To do this we have to solve problems associated with the distribution of limited resources. In this case, the technological interdependence between the works performed, which may be of a different nature, should be taken into account. As the results, new approaches were founded to developing a strategy for the selection of options for construction and installation works in order to ensure contractual deadlines for their implementation and minimize the funds spent on their implementation taking into account the nature of the dependencies between the works performed is an urgent and important problem.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Tapan Kumar Datta

This paper analyzes an inventory system for joint determination of product quality and selling price where a fraction of items produced are defective. It is assumed that only a fraction of defective items can be repaired/reworked. The demand rate depends upon both the quality and the selling price of the product. The production rate, unit price, and carrying cost depend upon the quality of the items produced. Quality index is used to determine the quality of the product. An algorithm is provided to solve the model with given values of model parameters. Sensitivity analysis has also been performed.


1996 ◽  
Vol 05 (03) ◽  
pp. 543-550
Author(s):  
VERED MAHAL ◽  
ADY ARIE

Two diode-pumped tunable Nd:YAG lasers locked to sub-Doppler transitions of 127I2 and 133 Cs 2 are used as a source for two-wavelength interferometry. The synthetic wavelength, Λ=c/∆ν, is highly stable and accurate, owing to the frequency stability of the locked lasers and the precise determination of the frequency difference Δν between Cs 2 and I 2 transitions. The dense spectra of these molecules allows selection of Λ over a wide range, between 8.5 mm and several meters, thus enabling distance measurements with a large non-ambiguity range. Fringe contrast and phase-shifting methods are used to measure the phase difference. An accuracy of 70 μm is achieved for Λ~19 mm, i.e. Λ/260.


Author(s):  
Alberto Falorni ◽  
Vittorio Bini ◽  
Corrado Betterle ◽  
Annalisa Brozzetti ◽  
Luis Castaño ◽  
...  

Abstract21-Hydroxylase autoantibodies (21OHAb) are markers of an adrenal autoimmune process that identifies individuals with autoimmune Addison’s disease (AAD). Quality and inter-laboratory agreement of various 21OHAb tests are incompletely known. The objective of the study was to determine inter-laboratory concordance for 21OHAb determinations.Sixty-nine sera from 51 patients with AAD and 51 sera from 51 healthy subjects were blindly coded by a randomization center and distributed to 14 laboratories that determined 21OHAb, either by an “in-house” assay (n=9) using in vitro-translatedIntra-assay coefficient of variation ranged from 2.6% to 5.3% for laboratories using the commercial kit and from 5.1% to 23% for laboratories using “in-house” assays. Diagnostic accuracy, expressed as area under ROC curve (AUC), varied from 0.625 to 0.947 with the commercial kit and from 0.562 to 0.978 with “in-house” methods. Cohen’s κ of inter-rater agreement was 0.603 among all 14 laboratories, 0.691 among “in-house” laboratories, and 0.502 among commercial kit users. Optimized cutoff levels, calculated on the basis of AUCs, increased the diagnostic accuracy of every laboratory (AUC >0.9 for 11/14 laboratories) and increased the Cohen’s κ of inter-rater agreement. Discrepancies in quantitation of 21OHAb levels among different laboratories increased with increasing autoantibody levels.The quality of 21OHAb analytical procedures is mainly influenced by selection of cutoff value and correct handling of assay materials. A standardization program is needed to identify common standard sera and common measuring units.


2018 ◽  
Vol 1 (1) ◽  
pp. 687-693
Author(s):  
Łukasz Bołoz

Abstract The article presents the results of a study on the quality of conical picks for the purposes of tender procedures in accordance with the public procurement law in Poland. The pick studies presented here are one of the few that in practice allow the selection of an offer based on objectively determined numerical indicators defining the quality of the product and not only on the basis of price. Thanks to this, the contracting party can decide the relevance of price and quality in their evaluation of a pick. The geometrical and material parameters required in a tender, if not met, are the basis for rejecting a given offer of picks. The numerical parameter influencing the final evaluation of the offer is the picks’ rate of wear. Conical picks are tools for mining minerals, rocks, asphalt or concrete. They are used in many industries, especially in mining, construction and road engineering. In difficult working conditions, the durability of knives is limited to as little as several hours. Several dozen picks work on a cutting unit at the same time, and taking into account the price of a knife which oscillates around several dozen euros, significant operating costs are incurred. Therefore, the selection of tools with an optimum price-quality ratio is crucial. The article presents the results of studies on geometric parameters, material parameters and the rate of wear of 48 sets of picks conducted for a tender consisting of 14 tasks. The tender was conducted for 6 underground mines of a coal company. Five producers submitted their offers for selected tasks in the tender.


Sensors ◽  
2019 ◽  
Vol 19 (14) ◽  
pp. 3179
Author(s):  
Tilen Urbančič ◽  
Žiga Roškar ◽  
Mojca Kosmatin Fras ◽  
Dejan Grigillo

The main goal of our research was to design and implement an innovative target that would be suitable for accurately registering point clouds produced from unmanned aerial vehicle (UAV) images and terrestrial laser scans. Our new target is composed of three perpendicular planes that combine the properties of plane and volume targets. The new target enables the precise determination of reference target points in aerial and terrestrial point clouds. Different types of commonly used plane and volume targets as well as the new target were placed in an established test area in order to evaluate their performance. The targets were scanned from multiple scanner stations and surveyed with an unmanned aerial vehicle DJI Phantom 4 PRO at three different altitudes (20, 40, and 75 m). The reference data were measured with a Leica Nova MS50 MultiStation. Several registrations were performed, each time with a different target. The quality of these registrations was assessed on the check points. The results showed that the new target yielded the best results in all cases, which confirmed our initial expectations. The proposed new target is innovative and not difficult to create and use.


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