Study on the Process of Creating Fly Ash Body

2014 ◽  
Vol 1000 ◽  
pp. 166-169
Author(s):  
Vit Cerný ◽  
Šárka Keprdová

Production of artificial aggregate by clinkering process is currently relatively well-known way to efficiently use the potential of fly ash for building materials. Principle of clinkering can reduce the cost of natural gas and other potential external sources of heat through the use of own combustible substances. Course of firing and aggregate properties significantly depend on the type and character of the fly ash or fly ash mixture. Due to the high heterogeneity of these materials is relatively difficult to assess the impact of specific parameters (grain size, the content of Fe2O3, SiO2, CaO, amorphous phase, etc.). Due to the experimental testing of a large number of different types of fly ash and their mixtures, it will possible to verify at least some principles based on experience with the production of ceramic body. This article discusses the results of the sub-tests, dealt with influence of physico-mechanical properties, chemical and mineralogical composition of fly ash on the quality of the resulting ash body.

2015 ◽  
Vol 1124 ◽  
pp. 170-176
Author(s):  
Vit Cerný

In a world is of ever-increasing pressure on the use of fly ash in building materials. Despite these efforts the majority of produced energy by-products end up as reclamation material and only small part as high-quality materials. Technology of sintered artificial aggregate is fully based on the fly ashes and allows processing a high percentage of this raw material. The work is devoted to assessing the impact of fly ash character on the quality artificial aggregate. There were selected three fly ashes from high-temperature combustion technology and two from the FBC combustion. The results clearly show that the FBC ashes are not too useful for sintered aggregate technology. For fly ashes is determined primarily by their fineness and the amount of amorphous silica phase.


2015 ◽  
Vol 6 (1) ◽  
pp. 50-57
Author(s):  
Rizqa Raaiqa Bintana ◽  
Putri Aisyiyah Rakhma Devi ◽  
Umi Laili Yuhana

The quality of the software can be measured by its return on investment. Factors which may affect the return on investment (ROI) is the tangible factors (such as the cost) dan intangible factors (such as the impact of software to the users or stakeholder). The factor of the software itself are assessed through reviewing, testing, process audit, and performance of software. This paper discusses the consideration of return on investment (ROI) assessment criteria derived from the software and its users. These criteria indicate that the approach may support a rational consideration of all relevant criteria when evaluating software, and shows examples of actual return on investment models. Conducted an analysis of the assessment criteria that affect the return on investment if these criteria have a disproportionate effort that resulted in a return on investment of a software decreased. Index Terms - Assessment criteria, Quality assurance, Return on Investment, Software product


2021 ◽  
pp. 1-21
Author(s):  
Davide Vittori

Abstract Scholars have long debated whether populism harms or improves the quality of democracy. This article contributes to this debate by focusing on the impact of populist parties in government. In particular, it inquires: (1) whether populists in government are more likely than non-populists to negatively affect the quality of democracies; (2) whether the role of populists in government matters; and (3) which type of populism is expected to negatively affect the quality of liberal-democratic regimes. The results find strong evidence that the role of populists in government affects several qualities of democracy. While robust, the findings related to (2) are less clear-cut than those pertaining to (1). Finally, regardless of their role in government, different types of populism have different impacts on the qualities of democracy. The results show that exclusionary populist parties in government tend to have more of a negative impact than other forms of populism.


2021 ◽  
Vol 30 (3) ◽  
pp. 1-56
Author(s):  
Mouna Abidi ◽  
Md Saidur Rahman ◽  
Moses Openja ◽  
Foutse Khomh

Nowadays, modern applications are developed using components written in different programming languages and technologies. The cost benefits of reuse and the advantages of each programming language are two main incentives behind the proliferation of such systems. However, as the number of languages increases, so do the challenges related to the development and maintenance of these systems. In such situations, developers may introduce design smells (i.e., anti-patterns and code smells) which are symptoms of poor design and implementation choices. Design smells are defined as poor design and coding choices that can negatively impact the quality of a software program despite satisfying functional requirements. Studies on mono-language systems suggest that the presence of design smells may indicate a higher risk of future bugs and affects code comprehension, thus making systems harder to maintain. However, the impact of multi-language design smells on software quality such as fault-proneness is yet to be investigated. In this article, we present an approach to detect multi-language design smells in the context of JNI systems. We then investigate the prevalence of those design smells and their impacts on fault-proneness. Specifically, we detect 15 design smells in 98 releases of 9 open-source JNI projects. Our results show that the design smells are prevalent in the selected projects and persist throughout the releases of the systems. We observe that, in the analyzed systems, 33.95% of the files involving communications between Java and C/C++ contain occurrences of multi-language design smells. Some kinds of smells are more prevalent than others, e.g., Unused Parameters , Too Much Scattering , and Unused Method Declaration . Our results suggest that files with multi-language design smells can often be more associated with bugs than files without these smells, and that specific smells are more correlated to fault-proneness than others. From analyzing fault-inducing commit messages, we also extracted activities that are more likely to introduce bugs in smelly files. We believe that our findings are important for practitioners as it can help them prioritize design smells during the maintenance of multi-language systems.


2020 ◽  
Vol 36 (1) ◽  
Author(s):  
Nesreen Fathi Mahmoud ◽  
Huda Zahran ◽  
Sherif Abdelmonam

Abstract Background This study focuses on the self-perception of the voice in the elderly as assessed by the Voice-Related Quality of Life (V-RQOL) questionnaire. This work aimed to compare differences in the voice-related quality of life outcomes between (1) elderly with and without voice disorders, (2) female and male elderly with voice disorders, and (3) different types of voice disorders, and to explore the correlation between the V-RQOL and perceptual analysis done by the clinician. Forty-three dysphonic and 44 non-dysphonic elderly filled out the Voice-Related Quality of Life (V-RQOL) protocol that analyzes the impact of dysphonia on life quality. Vocal perceptual assessment of each subject with dysphonia was made by three voice therapists, followed by a flexible nasofibrolaryngoscope. Results A significant statistical difference was found between the means of total V-RQOL scores and its subdomains for each group (dysphonic and non-dysphonic). No significant differences were found between male and female elderly with dysphonia. The statistical analysis showed a significant correlation with the vocal assessment made by the clinicians and the V-RQOL self-assessment made by the subjects. Conclusions This study provides valuable information regarding the risk factors that contribute to vocal quality in the elderly population. Our results revealed that different types of voice disorders are common among the elderly population with significant negative effects on quality of life. It was observed that the poorest score on the V-RQOL was for functional voice disorders, followed by neoplastic lesions, whereas MAPLs had the best score on the V-RQOL.


Author(s):  
А.О. РЕНЗЯЕВ ◽  
О.П. РЕНЗЯЕВ ◽  
С.Н. КРАВЧЕНКО ◽  
Р.В. КРЮК

Исследованы прочностные и физико-механические свойства оболочки рапса с точки зрения ее разрушения и удаления. Установлено, что наиболее рациональным является двухстадийный способ обрушивания: 1-я стадия – на вальцовых мельницах, 2-я – на центробежной обрушивающей машине. Определены параметры центробежной обрушивающей машины для обеспечения минимальной необходимой линейной скорости 10,81 м/с: угол наклона отбойной пластины (90 ± 2)°, частота вращения барабана (2400 ± 150) об/мин. Установлено, что правильно подобранные условия и угол, под которым происходит удар, позволяют значительно снизить количество не до конца обрушенного семени и содержание расколотого ядра. При этом при свободном ударе об отбойную пластину под углом, отличным от 88–91°, или подаче недостаточно равномерного потока семян значительно увеличивается содержание необрушенных семян. На разрушение 1 кг семян необходимо затратить 58,45 Дж. Таким образом, по расчетным данным, для семян рапса диаметром 1,5 мм частота вращения барабана должна находиться в диапазоне от 2221 до 2565 об/мин при ударе семени под углом 90°. Диаметр семян рапса, выращиваемого в Сибирском регионе, составляет от 0,8 до 1,8 мм. Установлено, что подсушивание семян рапса в течение 30–40 с при температуре 100°С позволяет увеличить эффективность разрушения оболочки до полного ее отделения от ядра рапса. Представленные результаты позволяют повысить качество очистки семян рапса от оболочки и улучшить качественные характеристики получаемого масла, облегчить последующие технологические процессы получения пищевого масла, снизить затраты на рафинацию и дезодорацию на 2%. The strength and physico-mechanical properties of the shell of rapeseed in terms of its destruction and removal are investigated. It is established that the most rational is a two-stage method of seed hulling: the 1st stage – on roller mills, the 2nd – on a centrifugal hulling machine. The parameters of the centrifugal hulling machine to provide the minimum required linear speed of 10,81 m/s are defined: the angle of inclination of the turnback plate (90 ± 2)°, the rotational speed of drum (2400 ± 150) RPM. It is established that the correctly selected conditions and the angle at which the impact occurs, can significantly reduce the amount is not completely hulling seed and the substance of the split nucleus. At the same time, with a free impact on the turnback plate at an angle different from 88–91°, or the supply of an insufficiently uniform flow of seeds, the content is not completely hulling seed increases significantly. On hulling of 1 kg of seeds it is necessary to spend 58,45 J. Thus, according to the calculated data, for rape seeds with a diameter of 1,5 mm, the rotational speed of drum should be in the range from 2221 to 2565 RPM when the seed is struck at an angle of 90°. The diameter of rapeseed grown in the Siberian region ranges from 0,8 to 1,8 mm. It was found that drying of rapeseed for 30–40 s at a temperature of 100°C, can increase the efficiency of destruction of the shell to its complete separation from the core of rapeseed. The presented results make it possible to improve the quality of cleaning of rape seeds from the shell and improve the quality characteristics of the obtained oil, facilitate the subsequent technological processes of obtaining edible oil, reduce the cost of refining and deodorization by 2%.


Author(s):  
Valentyna Fostolovych ◽  
Tetiana Botsian

The permeability of all spheres of both economic activity and human life with digital technologies encourages the search for new marketing ideas necessary for the implementation of the product (goods, works and services).  Today's consumer has become more demanding both to the product itself and to the ways of presenting it.  Immersive technologies are becoming one of the tools that contribute to the formation of competitive advantages, especially the organization of business in the field of entertainment, as one of the areas of additional income in the field of hotel and restaurant services and marketing activities of enterprises.  Digital transformation leads to the search for new initiatives that will be a tool to meet customer needs and a way to reach wider market segments.  The process of digitalization must first be integrated into the economy of the whole state and the enterprise as a whole, and in all processes of production of goods, works and services.  Digital-transformation of domestic enterprises will help to obtain additional competitive advantages both in the domestic market and in the international market.  The formation of competitive advantages is associated not only with the maximum involvement of digital technologies in business.  It is important to choose such technologies that will be most effective in the implementation of a particular type of enterprise, under certain conditions and in a particular environment. The expediency of using immersive technologies as a marketing tool is undeniable.  However, in addition to tools, immersive technologies are important as a means of education, a separate milestone in the field of entertainment, a means of psychological influence and more.  That is, the impact of this tool on the level of competitiveness of the enterprise in the environment of the demanding consumer is manifested: in the form of reducing the cost of attracting the client; active covert promotion through their use; improving the quality of the presented product (goods, works, services); ensuring the elasticity of the enterprise to the needs and requirements of consumers; the transition of the enterprise to an innovative type of development and active digitalization.


2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Ahmad Nurfiki Alwi ◽  
Arif Rahman Setiaji ◽  
Abdurrohim Kurnia Agung ◽  
Abdul Halim

The number of economic needs is one of the fundamental aspects to support the survival of every individual in an area.  If seen in general, the cost of building the building and residential community still use building materials and installation costs are relatively higher.  With the advancement of technology has found a lightweight brick that has better strength, lighter, faster installation and environmentally friendly, so many people began to switch to using lightweight bricks.  For now the price of lightweight brick is still expensive, but this deficiency is covered with the speed of mounting and light weight so overall lightweight brick usage on certain patterns is very profitable.  The use of cement on lightweight bricks leads to high production costs.  With the above problems we have a breakthrough to replace the cement by using zeozolites containing silica compounds that resemble one of the cement compounds.  In this research, cement replacement with Zeolite is 20%, 40% and 60%.  Before use Zeolite was first activated using Fly Ash ratio of 65% Zeolite: 35% Fly Ash and 50% Zeolite: 50% Fly Ash, also activated using Ca (OH) 2 ratio 65% Zeolite: 35% Ca (OH) 2  And 50% Zeolite: 50% Ca (OH) 2.  Thus, there are 15 compositions including the control composition, each composition will be made up of 10 specimens.  Hypothesis testing using two way anova, tested is the effect of cement change treatment with Zeolite and comparison of Zeolite composition with Fly Ash and Ca (OH) 2 to compressive strength, absorption and cost. Keywords: Zeolite, Cement, compressive strength, Cost


DYNA ◽  
2021 ◽  
Vol 88 (216) ◽  
pp. 38-47
Author(s):  
Joaquín Abellán García ◽  
Nancy Torres Castellanos ◽  
Jaime Antonio Fernandez Gomez ◽  
Andres Mauricio Nuñez Lopez

Ultra-high-performance concrete (UHPC) is a kind of high-tech cementitious material with superb mechanical and durability properties compared to other types of concrete. However, due to the high content of cement and silica fume used, the cost and environmental impact of UHPC is considerably higher than conventional concrete. For this reason, several efforts around the world have been made to develop UHPC with greener and less expensive local pozzolans. This study aimed to design and produce UHPC using local fly ash available in Colombia. A numerical optimization, based on Design of Experiments (DoE) and multi-objective criteria, was performed to obtain a mixture with the proper flow and highest compressive strength, while simultaneously having the minimum content of cement. The results showed that, despite the low quality of local fly ashes in Colombia, compressive strength values of 150 MPa without any heat treatment can be achieved.


2019 ◽  
Vol 296 ◽  
pp. 149-154
Author(s):  
Radomír Sokolář ◽  
Martin Nguyen

Fluid fuel combustion technology in coal-fired power plants is very popular in the Czech Republic, resulting in a relatively high production of a specific by-product - fluidized fly ash (class C according to ASTM definition), which differs from the classical high-temperature fly ash in mineralogical composition with a high sulphur content of anhydrite CaSO4. Fluidized ash is not yet used in the production of fired building materials, where it could be used as a source of calcium oxide (for example, the production of porous ceramic tiles). However, high volume of sulphur dioxide emissions during the re-firing of fluidized fly ash in ceramic raw materials mixtures has been solved. The aim of the paper is definition of temperature ranges of anhydrite decomposition (formation of SO2 emission) from pure class C (fluidized) fly ashes from different sources (power plants) depending on granulometry of fly ash especially.


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