scholarly journals Relations between Texture Coefficient and Energy Consumption of Gang Saws in Carbonate Rock Cutting Process

2018 ◽  
Vol 4 (2) ◽  
pp. 413 ◽  
Author(s):  
Alireza Dormishi ◽  
Mohammad Ataei ◽  
Reza Mikaeil ◽  
Reza Khalo Kakaei
Keyword(s):  
Energy Consumption ◽  
Carbonate Rocks ◽  
Carbonate Rock ◽  
Texture Coefficient ◽  
Rock Samples ◽  
Study Results ◽  
Texture Characteristics ◽  
The Relationship ◽  
Influential Parameters ◽  
Energy Consumption Rate

Texture coefficient is one of the most influential parameters in rock engineering specifications in various projects including drilling, cutting, permeability of all-section drilling devices, etc. Meanwhile, investigating and forecasting the energy consumption of saw cutters are one of the most important factors in estimating the cutting costs. The present study aims to investigate the relationship between rock texture characteristics and the amount of energy consumption of the gang saw machine in the process of cutting carbonate rocks. To evaluate the effects of texture on the rocks' engineering specifications, 14 carbonate rock samples were studied. A microscopic thin section was made from each rock specimen. Then, five digital images were taken from each section under a microscope and the values of area, environment, the largest diameter and the smallest diameter of all grains in each image were determined. Using these specifications, the coefficient of texture of all rock samples was calculated and the relationship between the texture coefficient and the rate of energy consumption of the gang saw machine was investigated for the studied samples. The study results indicated that there was a significant relation between the texture coefficient and energy consumption rate in the three groups of carbonate rocks.

EFFECT OF MINERAL COMPOSITION OF CARBONATE ROCKS ON THEIR PETROPHYSICAL PROPERTIES

2017 ◽  
Vol 35 (1) ◽  
Author(s):  
Mábia Ruana Silva de Sena ◽  
José Agnelo Soares
Keyword(s):  
Mineral Composition ◽  
Carbonate Rocks ◽  
Carbonate Rock ◽  
Mineral Content ◽  
Northeastern Brazil ◽  
Petrophysical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Rock Samples ◽  
Mineral Characterization

ABSTRACT. The construction of digital models from a set of x-ray tomography images of high resolution (μCT) acquired in rock samples is an innovative technique in growing use nowadays. The objectives of this study were: demonstrate the potential of this technique to quantify mineral content of 15 carbonate rock samples from northeastern Brazil, through μCT analysis; to compare the results with the analysis of X-ray diffraction (XRD); and to evaluate the effect of this mineral composition on the petrophysical properties of these rocks. The results achieved in the simulation of the mineral composition confirmed that the analyzed carbonate rock samples are mainly composed of calcite and or dolomite. In general the XRD results confirmed the mineral composition indicated by μCT, except for amorphous minerals and those with small contents (accessory minerals). The results show the content of major minerals controlling the petrophysical properties, especially grain density and elastic velocities. However, other factors which were assessed through the analysis of μCT, also significantly affected the elastic velocities: porosity, type of porosity (if intergranular or vugular) and proportion of microporosity present in the rock. Keywords: carbonates, microcomputed tomography, mineral characterization, petrophysics, x-ray diffraction. RESUMO. A construção de modelos digitais de rochas a partir de um conjunto de imagens de tomografia de raios de x de alta resolução (μCT) é uma técnica inovadora com uso crescente atualmente. Os objetivos deste estudo são demonstrar o potencial desta técnica para quantificar a composição mineral de quinze amostras de rochas carbonáticas oriundas de bacias sedimentares do nordeste brasileiro, através da análise dos dados de μCT, comparar os resultados com as análises de difração de raios x (DRX), e avaliar o efeito da composição mineral sobre as propriedades petrofísicas dessas rochas. Os resultados obtidos na simulação da composição mineral, através de μCT, indicam que as amostras são compostas principalmente por calcita e/ou dolomita. Em geral os resultados de DRX confirmaram a composição mineral indicada por μCT, exceto para minerais amorfos e para aqueles que apresentam pequenos teores (minerais acessórios). Os resultados demonstram que os minerais principais (com teores mais elevados) controlam as propriedades petrofísicas, especialmente a densidade de grãos e as velocidades elásticas. Entretanto, outros fatores, os quais foram avaliados através da análise de μCT, também afetaram de maneira significativa as velocidades elásticas: porosidade, tipo de porosidade (se intergranular ou vugular) e proporção de microporosidade presente na rocha. Palavras-chave: carbonatos, microtomografia de raios x, caracterização mineral, petrofísica, difração de raios x.

A Zeta Potentiometric Study on Effects of Ionic Composition and Rock-Saturation on Surface-Charge Interactions in Low-Salinity Water Flooding for Carbonate Formation

2021 ◽  
Author(s):  
Paras Himmat Gopani ◽  
Navpreet Singh ◽  
Hemanta Kumar Sarma ◽  
Digambar S. Negi ◽  
Padmaja S. Mattey
Keyword(s):  
Zeta Potential ◽  
Surface Charge ◽  
Carbonate Rocks ◽  
Carbonate Rock ◽  
Ionic Composition ◽  
Streaming Potential ◽  
Potentiometric Studies ◽  
Rock Samples ◽  
Streaming Current ◽  
Charge Interactions

Abstract As carbonate reservoirs are mostly oil-wet, the potential for the success of a waterflooding is lower. Therefore, a primary focus during waterflooding such reservoirs is on the ionic composition and salinity of injected brine which are able to impact the alteration of the rock wettability favorably by altering the surface charge towards a higher negative value or close to zero. The objective of this study is to employ zeta potentiometric studies comprising streaming potential and streaming current techniques to quantify the surface interactions and charges between the carbonate rock and fluid type as a function of the variations in its ionic state and rock saturation. Zeta potentiometric studies were conducted on carbonate rock samples to understand the behavior of different aqueous solutions by variation in the brine's salinity and ionic composition and the results were integrated with wettability studies. The concentrations of potential-determining ions (PDIs) such as SO42-, Mg2+ and Ca2+ in the injected brines are deemed responsible for altering the wettability state of the carbonate rocks. Several diluted brines (25%, 10% and 1% diluted seawater) and smart brines have been investigated. Smart brines were prepared by spiking the concentration of major PDIs. All zeta potential measurements were conducted using a specially designed zeta potentiometer sample-holding clamp capable of using the whole core plugs rather than pulverized rock samples. A major advantage of using the whole core sample is that the same core can be used in subsequent coreflooding tests, thus making zeta potentiometric results more relevant and representative for a particular rock-fluid system used in the study. The classical streaming potential and streaming current techniques were used for zeta potential measurement. The Fairbrother-Mastin approach was used where the streaming potential is measured against different pressure differentials. Measurements were also carried out for brines with rock samples of different states: oil-saturated, water-saturated and rock samples cleaned with organic solvents to determine any likely variations in surface charge interactions. The results of our experiments imply that the value of zeta potential either increases or becomes more negative with increasing percentage of dilution (25%, 10%, and 1%). This can be attributed to electrical double-layer expansion which is primarily caused by reduced ionic strength. Furthermore, with measurements done on smart brines, zeta potential value was also found to be increased when different diluted brines are spiked with ionic concentration of PDIs such as sulfate. This could have been caused by surface ion alteration mechanism where PDIs get adsorbed on rock surface causing possible detachment of oil droplets. Both the phenomena are known mechanisms for altering wettability towards more water wetness in carbonate rocks and are discussed in detail.

Moderating Role of Gender in the Relationship between Cognitive Errors and Anxiety among Adolescents

2020 ◽  
Vol 4 (1) ◽  
pp. 86-102
Author(s):  
Tasnim Rehna ◽  
Rubina Hanif ◽  
Muhammad Aqeel
Keyword(s):  
Mental Health Problems ◽  
Adolescent Psychopathology ◽  
Future Research ◽  
Cognitive Errors ◽  
Adolescent Anxiety ◽  
Study Results ◽  
The Status ◽  
Manifest Anxiety ◽  
The Relationship

Background: Widespread social paradigms on which the status variances are grounded in any society, gender plays pivotal role in manifestation of mental health problems (Rutter, 2007). A hefty volume of research has addressed the issue in adults nonetheless, little is vividly known about the role of gender in adolescent psychopathology. Sample: A sample of 240 adolescents (125 boys, 115 girls) aging 12-18 years was amassed from various secondary schools of Islamabad with the approval of the Federal Directorate of Education (FDE), relevant authorities of the schools and the adolescents themselves. Instruments: Taylor Manifest Anxiety Scale (Taylor & Spence, 1953) and Children’s Negative Cognitive Errors Questionnaire (CNCEQ) by Leitenberg et al., (1986) were applied in present study. Results: Multiple regression analysis revealed that cognitive errors jointly accounted for 78% of variance in predicting anxiety among adolescents. Findings also exhibited that gender significantly moderated the relationship between cognitive errors and adolescent anxiety. Implications of the findings are discoursed for future research and clinical practice.

RECREATION SPECIALIZATION FOR RUNNERS AND EVENT ATTACHMENT

2020 ◽  
Author(s):  
Isao Okayasu ◽  
Chi-Ok Oh ◽  
Duarte B Morais
Keyword(s):  
Practical Implication ◽  
Event Management ◽  
Attitudes And Behaviors ◽  
The Third ◽  
Study Results ◽  
The World ◽  
Recreation Specialization ◽  
And Behaviors ◽  
The Relationship ◽  
Predictive Relationship

Running is one of the most popular activities in the world. Runners’ attitudes and behaviors vary depending on their running style. This study aims to construct different measures of running specialization based on the theory of specialization. This study also tests a runner’s stage of specialization segmentation based on recreation specialization and examines the predictive relationship between a runner’s specialization and event attachment. Three groups of sampling data assess the performance of diverse specialization measures for running in three marathon events. First, two surveys were conducted with marathon participants to assess the performance of diverse specialization measures for runners. Second, the third dataset was used to examine the relationship between a runner’s recreation specialization and event attachment.The study results showed that the 15 measures of specialization showed a good fit to the data. Our research showed how runners’ recreation specialization is connected to their event attachment. In addition, this study suggested event management for subdivisions of runners. Its practical implication is that recreation specialization for running can help us understand event attachment.

Motivating and Retaining Festival Patronage

2020 ◽  
Vol 24 (4) ◽  
pp. 447-461
Author(s):  
Michelle (Myongjee) Yoo ◽  
Miranda Kitterlin-Lynch ◽  
Bomin Kim
Keyword(s):  
Structural Equation ◽  
Customer Relationship ◽  
Equation Modeling ◽  
Organization And Management ◽  
Customer Relationship Marketing ◽  
Study Results ◽  
And Behavior ◽  
The Relationship ◽  
Self Administered Questionnaire ◽  
Theoretical Foundations

Globally, festivals and host communities face increased competition each year from one another and from the myriad of alternate entertainment options. To remain competitive, festival organizers must fully understand what keeps festival attendees coming back year after year. Festivalscape has been an emerging concept of value in this arena, and previous studies have found that festivalscape has an effect on the attendees' emotion and behavior that influences their overall perceived value of the festival. The purpose of this study is to examine the relationship between festivalscape and the attendees' motivation, satisfaction, and loyalty. A self-administered questionnaire was developed and a structural equation modeling (SEM) was employed to test the proposed hypotheses. Study results support the hypotheses, indicating the importance of using festivalscape factors for festival organization and management and effective customer relationship marketing. Further, this study provides academic contributions to theoretical foundations by confirming the effects of these factors. This study also provides practical implications for managing festivals effectively and successfully.

The Impact of Bar Service Operation Practices on Organizational Performance in Indian Hotel Industry

2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Mohinder C. Dhiman ◽  
Abhishek Ghai
Keyword(s):  
Organizational Performance ◽  
Hotel Industry ◽  
Demographic Variables ◽  
Study Results ◽  
Service Operation ◽  
Managerial Implications ◽  
Overall Performance ◽  
The Impact ◽  
The Relationship ◽  
Bivariate Test

The paper has a two fold purpose - examine the impact of bar service operation practices (BSOP) on organizational performance (OP) and study the relationship between organizational performance and demographic variables. Based on a survey of 362 bar managers perceptions on the impact of bar service operation practices on organizational performance were assessed by 59 practices and 6 demographic variables. Bivariate test and ANOVA were employed to test the working hypothesis in the study. Results indicated that there is a positive relationship between the bar service operation practices and organizational performance. Further, the results indicate some practical and managerial implications to improve organizational overall performance.

Acculturative stress and life satisfaction of Chinese rural-to-urban migrants

2020 ◽  
Vol 48 (11) ◽  
pp. 1-11
Author(s):  
Dekuo Liang ◽  
Lei Wang ◽  
Liying Xia ◽  
Dawei Xu
Keyword(s):  
Social Support ◽  
Life Satisfaction ◽  
Acculturative Stress ◽  
Perceived Social Support ◽  
Well Being ◽  
Self Esteem ◽  
Construction Sites ◽  
Urban Migrants ◽  
Study Results ◽  
The Relationship

Little is known regarding the life satisfaction of rural-to-urban migrants in China. In this study we assessed whether self-esteem and perceived social support mediated the association between rural-to-urban migrants' acculturative stress and life satisfaction. We use convenience sampling to recruit 712 migrants who were employed at construction sites in Nanjing for the study. Results reveal that acculturative stress was negatively related to self-esteem, perceived social support, and life satisfaction; self-esteem was positively associated with perceived social support and life satisfaction; and perceived social support was a significant and positive predictor of life satisfaction. In addition, we found that self-esteem and perceived social support partially mediated the relationship between acculturative stress and life satisfaction. Our findings provide a better understanding of life satisfaction over the course of migration, and add to knowledge of psychological well-being and mental health among rural-to-urban migrants in China.

scholarly journals Empirical Research on the Relationship amongst Renewable Energy Consumption, Economic Growth and Foreign Direct Investment in Kazakhstan and Uzbekistan

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 332
Author(s):  
Janusz Grabara ◽  
Arsen Tleppayev ◽  
Malika Dabylova ◽  
Leonardus W. W. Mihardjo ◽  
Zdzisława Dacko-Pikiewicz
Keyword(s):  
Economic Growth ◽  
Foreign Direct Investment ◽  
Renewable Energy ◽  
Energy Consumption ◽  
Direct Investment ◽  
Renewable Energy Sources ◽  
Energy Sources ◽  
Renewable Energy Consumption ◽  
Integration Test ◽  
The Relationship

In this contemporary era, environmental problems spread at different levels in all countries of the world. Economic growth does not just depend on prioritizing the environment or improving the environmental situation. If the foreign direct investment is directed to the polluting industries, they will increase pollution and damage the environment. The purpose of the study is to consider the relationship between foreign direct investment in Kazakhstan and Uzbekistan and economic growth and renewable energy consumption. The study is based on data obtained from 1992 to 2018. The results show that there is a two-way link between foreign direct investment and renewable energy consumption in the considered two countries. The Granger causality test approach is applied to explore the causal relationship between the variables. The Johansen co-integration test approach is also employed to test for a relationship. The empirical results verify the existence of co-integration between the series. The main factors influencing renewable energy are economic growth and electricity consumption. To reduce dependence on fuel-based energy sources, Kazakhstan and Uzbekistan need to attract energy to renewable energy sources and implement energy efficiency based on rapid progress. This is because renewable energy sources play the role of an engine that stimulates the production process in the economy for all countries.

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