Search results for: model building
2525 Effect of Organophilic Clay on the Stability and Rheological Behavior of Oil-Based Drilling Muds
Authors: Hammadi Larbi
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The major problem with oil-based drilling muds (reverse emulsions) is their thermodynamic instability and their high tendency to coalescence over time, irreversibly leading to destabilization. Water/Oil reverse emulsion drilling Muds are highly recommended when significant depths are reached. This study aimed to contribute experimentally to the knowledge of the structure (stability) and rheological behavior of drilling mud systems based on water/crude oil inverse emulsions through the investigation of the effect of organophilic clay. The chemical composition of organophilic clay such as VG69 shows a strong presence of silicon oxide (SiO2), followed by aluminum oxide (Al2O3), so these two elements are considered to be the main constituents of organophilic clays. The study also shows that the SiO2/Al2O3 ratio is equal to 3.52, which can be explained by the high content of free silica contained in the organophile clay used. The particle size analysis of the organophilic clays showed that the size of the of the particles analysed is in the range of 30 to 80 μm, this result ensures the correct particle size quality of organophilic clays and allows these powders to be used in Drilling mud systems.The experimental data of steady-state flow measurements are analyzed in the classic way by the Herschel-Bulkley model. Microscopic observation shows that the addition of quantities of organophilic clay type VG69 less than or equal to 3 g leading to the stability of the water/oil inverse emulsions, on the other hand, for quantities greater than 3 g, the emulsions are destabilized. The results obtained also showed that adding 3 g of organophilic clay to the crude oil drilling mud improves their stability by 70%.Keywords: drilling muds, inverse emulsions, rheological behavior, yield stress, stability, organophilic clay
Procedia PDF Downloads 132524 The Effects of Country of Manufacture and Country of Brand on Purchase Intention: The Moderating Role of Brand Experience
Authors: Natinee Thanajaro
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In the past few decades, international research on the country of origin of products has garnered significant interest, particularly in investigating the effects of consumers’ evaluation and perception. As globalization and market competition rise, international firms are seeking ways to control their labour costs and minimise taxes. Many products are outsourced and manufactured in countries with cheap labour. Consequently, the proliferation of ‘bi-national’ products has increased, raising important questions related to consumers’ perception. Moreover, the rapid growth in emerging markets, especially in Asia, has made these countries attractive options for international brands. Therefore, studying the country of origin allows firms and researchers to understand how customers perceive such information regarding the country of manufacture and the country of the brand. This study aims to investigate the influence of the country of manufacture (COM) and country of brand (COB) on Thai consumers’ perception of the brand. In addition, it embraces a different perspective on brand experience as a moderating factor. A sample of 403 Thai respondents was collected through face-to-face survey questionnaires in central Bangkok. This research employs an experiment using a factorial design to test the hypotheses. SPSS statistics software was adopted to analyse and validate the reliability of the testing of the constructs and model hypotheses. The results of this research show that the respondents positively respond to the COB more than the COM, and brand experience plays a moderating role in this research. This research provides a significant contribution to the existing literature and managerial practicality by using multi-dimensional information on the country and analyses the relationships between these dimensions.Keywords: brand experience, country of brand, country of manufacture, purchase intention
Procedia PDF Downloads 1252523 Seven Brothers and Sisters of Severely Disabled Children Speak up about Their Everyday Challenges and Needs : A Multiple Case Study
Authors: Myriam Castonguay, Florence Vinit
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This study aims to gain a better understanding of the lived experience of seven children growing up in a family where another child is severely disabled, informed by family systems theory and the socio-ecological model of development. In depth semi-structured interviews were conducted with seven children who described they everyday life since their brother’s or sister’s diagnosis. Thematic analysis revealed four themes : struggling with loneliness inside the family, supporting the disabled child through its journey, accommodating to a changing routine and keeping a “bubble” for oneself. Brothers and sisters depict a family life characterized by much loneliness, with severe disabilities requiring ongoing care and prolonged hospitalizations. In the midst of adversity, siblings describe themselves as highly committed to supporting the disabled child and to preserve family cohesion, even if that means getting exposed to emotionally challenging situations and adjusting their daily routine frequently. Children recount that keeping up with schoolwork and leisure activities of their own is central to their well-being. Having a space where one can reconnect with his ordinary life as a kid is also deemed very important. This study reminds us that more needs to be done to counteract the loneliness experienced by siblings through the family experience of disability. Family members and clinicians need to be extra vigilant to ensure siblings’ needs don’t go unnoticed or dismissed, as it may be difficult for this population of children to voice their own experience and needs. Family, school and other actors in the community may help brothers and sisters pursue their personal dreams, goals and projects, to continue experiencing well-being despite adverse life circumstances.Keywords: sibling’s lived experience of disability, sibling’s needs at various levels of the ecosystem, family adjustment to the disability experience, supporting family wellness through the disability experience
Procedia PDF Downloads 1162522 Frequency of Alloimmunization in Sickle Cell Disease Patients in Africa: A Systematic Review with Meta-analysis
Authors: Theresa Ukamaka Nwagha, Angela Ogechukwu Ugwu, Martins Nweke
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Background and Objectives: Blood transfusion is an effective and proven treatment for some severe complications of sickle cell disease. Recurrent transfusions have put patients with sickle cell disease at risk of developing antibodies against the various antigens they were exposed to. This study aims to investigate the frequency of red blood cell alloimmunization in patients with sickle disease in Africa. Materials and Methods: This is a systematic review of peer-reviewed literature published in English. The review was conducted consistent with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. Data sources for the review include MEDLINE, PubMed, CINAHL, and Academic Search Complete. Included in this review are articles that reported the frequency/prevalence of red blood cell alloimmunization in sickle cell disease patients in Africa. Eligible studies were subjected to independent full-text screening and data extraction. Risk of bias assessment was conducted with the aid of the mixed method appraisal tool. We employed a random-effects model of meta-analysis to estimate the pooled prevalence. We computed Cochrane’s Q statistics and I2 and prediction interval to quantify heterogeneity in effect size. Results: The prevalence estimates range from 2.6% to 29%. Pooled prevalence was estimated to be 10.4% (CI 7.7.–13.8); PI = 3.0 – 34.0%), with significant heterogeneity (I2 = 84.62; PI = 2.0-32.0%) and publication bias (Egger’s t-test = 1.744, p = 0.0965). Conclusion: The frequency of red cell alloantibody varies considerably in Africa. The alloantibodies appeared frequent in this order: the Rhesus, Kell, Lewis, Duffy, MNS, and LutheranKeywords: frequency, red blood cell, alloimmunization, sickle cell disease, Africa
Procedia PDF Downloads 992521 Factors Affecting Context of Innovation: A Case Study of a Farming-as-a-Service Company
Authors: Kunal Mankodi, Sudhir Pandey
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This study aims to assess the factors that play a role in setting up and running a social enterprise driven towards sustainability at the intersection of energy, environment, and poverty alleviation. According to the theory of sustainability-oriented innovation (SOI), conventional organisations adapt their processes to focus on sustainability-oriented innovations. On the other hand, social enterprises that are purpose-driven are also influenced by the context of innovation, which need due attention. This paper presents an account of innovation at Oorja - an Indian social enterprise operating with a farming-as-a-service business model. It aims to illustrate the contexts in which the innovative solutions were developed to work at an intersection between agriculture and clean energy, thereby allowing small farmers access to efficient solutions in the agriculture cycle. Primary data was collected through in-depth interviews, and secondary data was collected from company sources. The study finds that in the case of a social enterprise, the definition of innovation assumes a wider scope by going beyond the introduction of a new product/service. The context of innovation for social enterprise is affected by organisational factors such as organisation’s philosophical mindset, behaviour towards innovation, organisation’s capabilities, regulatory environment, and customer receptiveness. Additionally, the study also finds that the context of innovation for a social enterprise is affected by its organizational structure. A majority of these organizational factors are, in turn, affected by individual (Founder’s) factors such as the founder’s formative years, education, direct exposure to relevant issues, complementary skills of co-founders, and a common calling.Keywords: context of innovation, social enterprise, sustainability oriented innovations, emerging markets, agriculture
Procedia PDF Downloads 1432520 Multi-Index Performance Investigation of Rubberized Reclaimed Asphalt Mixture
Authors: Ling Xu, Giuseppe Loprencipe, Antonio D'Andrea
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Asphalt pavement with recycled and sustainable materials has become the most commonly adopted strategy for road construction, including reclaimed asphalt pavement (RAP) and crumb rubber (CR) from waste tires. However, the adhesion and cohesion characteristics of rubberized reclaimed asphalt pavement were still ambiguous, resulting in deteriorated adhesion behavior and life performance. This research investigated the effect of bonding characteristics on rutting resistance and moisture susceptibility of rubberized reclaimed asphalt pavement in terms of two RAP sources with different oxidation levels and two tire rubber with different particle sizes. Firstly, the binder bond strength (BBS) test and bonding failure distinguishment were conducted to analyze the surface behaviors of binder-aggregate interaction. Then, the compatibility and penetration grade of rubberized RAP binder were evaluated by rotational viscosity test and penetration test, respectively. Hamburg wheel track (HWT) test with high-temperature viscoelastic deformation analysis was adopted, which illustrated the rutting resistance. Additionally, a water boiling test was employed to evaluate the moisture susceptibility of the mixture and the texture features were characterized with the statistical parameters of image colors. Finally, the colloid structure model of rubberized RAP binder with surface interaction was proposed, and statistical analysis was established to release the correlation among various indexes. This study concluded that the gel-phase colloid structure and molecular diffusion of the free light fraction would affect the surface interpretation with aggregate, determining the bonding characteristic of rubberized RAP asphalt.Keywords: bonding characteristics, reclaimed asphalt pavement, rubberized asphalt, sustainable material
Procedia PDF Downloads 622519 Electronic Commerce in Georgia: Problems and Development Perspectives
Authors: Nika GorgoShadze, Anri Shainidze, Bachuki Katamadze
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In parallel to the development of the digital economy in the world, electronic commerce is also widely developing. Internet and ICT (information and communication technology) have created new business models as well as promoted to market consolidation, sustainability of the business environment, creation of digital economy, facilitation of business and trade, business dynamism, higher competitiveness, etc. Electronic commerce involves internet technology which is sold via the internet. Nowadays electronic commerce is a field of business which is used by leading world brands very effectively. After the research of internet market in Georgia, it was found out that quality of internet is high in Tbilisi and is low in the regions. The internet market of Tbilisi can be evaluated as high-speed internet service, competitive and cost effective internet market. Development of electronic commerce in Georgia is connected with organizational and methodological as well as legal problems. First of all, a legal framework should be developed which will regulate responsibilities of organizations. The Ministry of Economy and Sustainable Development will play a crucial role in creating legal framework. Ministry of Justice will also be involved in this process as well as agency for data exchange. Measures should be taken in order to make electronic commerce in Georgia easier. Business companies may be offered some model to get low-cost and complex service. A service centre should be created which will provide all kinds of online-shopping. This will be a rather interesting innovation which will facilitate online-shopping in Georgia. Development of electronic business in Georgia requires modernized infrastructure of telecommunications (especially in the regions) as well as solution of institutional and socio-economic problems. Issues concerning internet availability and computer skills are also important.Keywords: electronic commerce, internet market, electronic business, information technology, information society, electronic systems
Procedia PDF Downloads 3842518 Lucilia Sericata Netrin-A: Secreted by Salivary Gland Larvae as a Potential to Neuroregeneration
Authors: Hamzeh Alipour, Masoumeh Bagheri, Tahereh Karamzadeh, Abbasali Raz, Kourosh Azizi
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Netrin-A, a protein identified for conducting commissural axons, has a similar role in angiogenesis. In addition, studies have shown that one of the netrin-A receptors is expressed in the growing cells of small capillaries. It will be interesting to study this new group of molecules because their role in wound healing will become clearer in the future due to angiogenesis. The greenbottle blowfly Luciliasericata (L. sericata) larvae are increasingly used in maggot therapy of chronic wounds. This aim of this was the identification of moleculareatures of Netrin-A in L. sericata larvae. Larvae were reared under standard maggotarium conditions. The nucleic acid sequence of L. sericataNetrin-A (LSN-A) was then identified using Rapid Amplification of cDNA Ends (RACE) and Rapid Amplification of Genomic Ends (RAGE). Parts of the Netrin-A gene, including the middle, 3′-, and 5′-ends were identified, TA cloned in pTG19 plasmid, and transferred into DH5ɑ Escherichia coli. Each part was sequenced and assembled using SeqMan software. This gene structure was further subjected to in silico analysis. The DNA of LSN-A was identified to be 2407 bp, while its mRNA sequence was recognized as 2115 bp by Oligo0.7 software. It translated the Netrin-A protein with 704 amino acid residues. Its molecular weight is estimated to be 78.6 kDa. The 3-D structure ofNetrin-A drawn by SWISS-MODEL revealed its similarity to the Netrin-1 of humans with 66.8% identity. The LSN-A protein conduces to repair the myelin membrane in neuronal cells. Ultimately, it can be an effective candidate in neural regeneration and wound healing. Furthermore, our next attempt is to deplore recombinant proteins for use in medical sciences.Keywords: maggot therapy, netrin-A, RACE, RAGE, lucilia sericata
Procedia PDF Downloads 1092517 Supervisory Emotional Display Affects Employee’s Well-Being
Authors: Huan Zhang, Darius K. S Chan
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Despite a large number of studies linking emotional labor and its detrimental impact for laborer, research on how emotional labor would influence the receiver is still in its infancy. Especially under the call for “people management”, supervisors inside the organization are more inclined to display happy mood to support their employees, thus endorsing emotional labor. The present study focuses on the employees in the service industry as emotional labor recipients and investigates how they respond to their supervisors’ emotional display, given their sensitivity to emotional cues. Targeted at a sample of 250 survey data from a wide range of customer service professions, this ongoing study examines how perceived supervisory emotional labor would moderate the relationship between employees surface acting and their well-being. Our major hypotheses are that employees’ surface acting predicts well-being level, and that perceived supervisory emotional labor to moderate the surface acting—outcome links. Preliminary findings have provided some support to the hypothesized model. Specifically, supervisors who are perceived to be high in surface acting are also regarded as fake and pseudo, hence the enhancing the detrimental effect of employees’ surface acting is attenuated, resulting in lower job satisfaction, higher physical stress and burnout; whereas perceived high supervisor’s deep acting, as associated with genuine and authenticity, buffers the negative impact and leads to higher job satisfaction, lower physical stress and burnout. This study first confirms the negative impacts of the surface acting on well-being for service industry employees as laborer and then extends the emotional labor studies by considering them as recipients of supervisory emotional labor. The findings provide insights for leaders by pointing out the importance of authentic emotional expression in workplace.Keywords: perceived supervisory emotional labor, surface acting, well-being
Procedia PDF Downloads 3952516 Geochemistry of Cenozoic basaltic rocks from Jiashan County of Nushan Geopark, China: Implications for Petrogenesis and Tectonic Setting
Authors: Dixon, Lieh-Chi Su, Hsiao-Ling Yu, Ren-Yi Huang, Yung-Tan Lee
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The present paper analyzed the major, trace elements, rare earth elements of these Cenozoic basalts and combined with Sr-Nd isotopic compositions to discuss the petrogenesis of these basalts and the tectonic setting of the study area. Based on major, trace elements and fractional crystallization model we suggest that the basaltic magma has experienced olivine, clinopyroxene, and plagioclase fractionation during its evolution. Spidergrams and REE patterns reveal that Cenozoic basalts found in the Jiashan County, Anhui Province have geochemical characteristics similar to those of ocean island basalts(OIB) suggesting a derivation related to OIB-like mantle source. The slight positive Nb and Ti anomalies found in basaltic rocks of this study suggest the presence of Ti-bearing minerals in the mantle source and these Ti-bearing minerals had contributed to basaltic magma during partial melting, indicating a metasomatic event might have occurred before the partial melting. Based on 143Nd/144Nd vs. 87Sr/86Sr diagram we suggest that basalts of this study can be produced by MORB and EM-I components mixing and small degree of partial melting may be the major controlling factor during generation of basaltic magma. Some basaltic magma may be derived from partial melting of EM-Ⅰ heated by the upwelling asthenospheric mantle. The basalts fall within the WPB field in the discriminant plot of 2Nb-Zr/4-Y indicate that the volcanic activities in this region may be closely related to deep continental rifting process.Keywords: geochemistry, cenozoic basalts, Anhui Province, Nushan Geopark, tectonic setting, fractionation
Procedia PDF Downloads 3462515 A Methodology to Integrate Data in the Company Based on the Semantic Standard in the Context of Industry 4.0
Authors: Chang Qin, Daham Mustafa, Abderrahmane Khiat, Pierre Bienert, Paulo Zanini
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Nowadays, companies are facing lots of challenges in the process of digital transformation, which can be a complex and costly undertaking. Digital transformation involves the collection and analysis of large amounts of data, which can create challenges around data management and governance. Furthermore, it is also challenged to integrate data from multiple systems and technologies. Although with these pains, companies are still pursuing digitalization because by embracing advanced technologies, companies can improve efficiency, quality, decision-making, and customer experience while also creating different business models and revenue streams. In this paper, the issue that data is stored in data silos with different schema and structures is focused. The conventional approaches to addressing this issue involve utilizing data warehousing, data integration tools, data standardization, and business intelligence tools. However, these approaches primarily focus on the grammar and structure of the data and neglect the importance of semantic modeling and semantic standardization, which are essential for achieving data interoperability. In this session, the challenge of data silos in Industry 4.0 is addressed by developing a semantic modeling approach compliant with Asset Administration Shell (AAS) models as an efficient standard for communication in Industry 4.0. The paper highlights how our approach can facilitate the data mapping process and semantic lifting according to existing industry standards such as ECLASS and other industrial dictionaries. It also incorporates the Asset Administration Shell technology to model and map the company’s data and utilize a knowledge graph for data storage and exploration.Keywords: data interoperability in industry 4.0, digital integration, industrial dictionary, semantic modeling
Procedia PDF Downloads 942514 Effect of 8 Weeks of Intervention on Physical Fitness, Hepatokines, and Insulin Resistance in Obese Subjects
Authors: Adela Penesova, Zofia Radikova, Boris Bajer, Andrea Havranova, Miroslav Vlcek
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Background: The aim of our study was to compare the effect of intensified lifestyle intervention on insulin resistance (HOMA-IR), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and Fibroblast growth factor (FGF) 21 after 8 weeks of lifestyle intervention. Methods: A group of 43 obese patients (13M/30F; 43.0±12.4 years; BMI (body mass index) 31.2±6.3 kg/m2 participated in a weight loss interventional program (NCT02325804) following an 8-week hypocaloric diet (-30% energy expenditure) and physical activity 150 minutes/week. Insulin sensitivity was evaluated according to the homeostasis model assessment of insulin resistance (HOMA-IR) and insulin sensitivity indices according to Matsuda and Cederholm were calculated (ISImat and ISIced). Plasma ALT, AST, Fetuin-A, FGF 21, and physical fitness were measured. Results: The average reduction of body weight was 6.8±4.9 kg (0-15 kg; p=0.0006), accompanied with a significant reduction of body fat amount of fat mass (p=0.03), and waist circumference (p=0.02). Insulin sensitivity has been improved (IR HOMA 2.71±3.90 vs 1.24±0.83; p=0.01; ISIMat 6.64±4.38 vs 8.93±5.36 p ≤ 0.001). Total, LDL cholesterol, and triglycerides decreased (p=0.05, p=0.04, p=0.04, respectively). Physical fitness significantly improved after intervention (as measure VO2 max (maximal oxygen uptake) (p ≤ 0.001). ALT decreased significantly (0.44±0.26 vs post 0.33±0.18 ukat/l, p=0.004); however, AST not (pre 0.40±0.15 vs 0.35±0.09 ukat/l, p=0.07). Hepatokine Fetuin-A significantly decreased after intervention (43.1±10.8 vs 32.6±8.6 ng/ml, p < 0.001); however, FGF 21 levels tended to decrease (146±152 vs 132±164 pg/ml, p=0.07). Conclusion: 8-weeks of diet and physical activity intervention program in obese otherwise healthy subjects led to an improvement of insulin resistance parameters and liver marker profiles, as well as increased physical fitness. This study was supported by grants APVV 15-0228; VEGA 2/0161/16.Keywords: obesity, diet, exercice, insulin sensitivity
Procedia PDF Downloads 2012513 Synthesis and Characterization of CNPs Coated Carbon Nanorods for Cd2+ Ion Adsorption from Industrial Waste Water and Reusable for Latent Fingerprint Detection
Authors: Bienvenu Gael Fouda Mbanga
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This study reports a new approach of preparation of carbon nanoparticles coated cerium oxide nanorods (CNPs/CeONRs) nanocomposite and reusing the spent adsorbent of Cd2+- CNPs/CeONRs nanocomposite for latent fingerprint detection (LFP) after removing Cd2+ ions from aqueous solution. CNPs/CeONRs nanocomposite was prepared by using CNPs and CeONRs with adsorption processes. The prepared nanocomposite was then characterized by using UV-visible spectroscopy (UV-visible), Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction pattern (XRD), scanning electron microscope (SEM), Transmission electron microscopy (TEM), Energy-dispersive X-ray spectroscopy (EDS), Zeta potential, X-ray photoelectron spectroscopy (XPS). The average size of the CNPs was 7.84nm. The synthesized CNPs/CeONRs nanocomposite has proven to be a good adsorbent for Cd2+ removal from water with optimum pH 8, dosage 0. 5 g / L. The results were best described by the Langmuir model, which indicated a linear fit (R2 = 0.8539-0.9969). The adsorption capacity of CNPs/CeONRs nanocomposite showed the best removal of Cd2+ ions with qm = (32.28-59.92 mg/g), when compared to previous reports. This adsorption followed pseudo-second order kinetics and intra particle diffusion processes. ∆G and ∆H values indicated spontaneity at high temperature (40oC) and the endothermic nature of the adsorption process. CNPs/CeONRs nanocomposite therefore showed potential as an effective adsorbent. Furthermore, the metal loaded on the adsorbent Cd2+- CNPs/CeONRs has proven to be sensitive and selective for LFP detection on various porous substrates. Hence Cd2+-CNPs/CeONRs nanocomposite can be reused as a good fingerprint labelling agent in LFP detection so as to avoid secondary environmental pollution by disposal of the spent adsorbent.Keywords: Cd2+-CNPs/CeONRs nanocomposite, cadmium adsorption, isotherm, kinetics, thermodynamics, reusable for latent fingerprint detection
Procedia PDF Downloads 1212512 Amazonian Native Biomass Residue for Sustainable Development of Isolated Communities
Authors: Bruna C. Brasileiro, José Alberto S. Sá, Brigida R. P. Rocha
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The Amazon region development was related to large-scale projects associated with economic cycles. Economic cycles were originated from policies implemented by successive governments that exploited the resources and have not yet been able to improve the local population's quality of life. These implanted development strategies were based on vertical planning centered on State that didn’t know and showed no interest in know the local needs and potentialities. The future of this region is a challenge that depends on a model of development based on human progress associated to intelligent, selective and environmentally safe exploitation of natural resources settled in renewable and no-polluting energy generation sources – a differential factor of attraction of new investments in a context of global energy and environmental crisis. In this process the planning and support of Brazilian State, local government, and selective international partnership are essential. Residual biomass utilization allows the sustainable development by the integration of production chain and energy generation process which could improve employment condition and income of riversides. Therefore, this research discourses how the use of local residual biomass (açaí lumps) could be an important instrument of sustainable development for isolated communities located at Alcobaça Sustainable Development Reserve (SDR), Tucuruí, Pará State, since in this region the energy source more accessible for who can pay are the fossil fuels that reaches about 54% of final energy consumption by the integration between the açaí productive chain and the use of renewable energy source besides it can promote less environmental impact and decrease the use of fossil fuels and carbon dioxide emissions.Keywords: Amazon, biomass, renewable energy, sustainability
Procedia PDF Downloads 3042511 Review of Numerical Models for Granular Beds in Solar Rotary Kilns for Thermal Applications
Authors: Edgar Willy Rimarachin Valderrama, Eduardo Rojas Parra
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Thermal energy from solar radiation is widely present in power plants, food drying, chemical reactors, heating and cooling systems, water treatment processes, hydrogen production, and others. In the case of power plants, one of the technologies available to transform solar energy into thermal energy is by solar rotary kilns where a bed of granular matter is heated through concentrated radiation obtained from an arrangement of heliostats. Numerical modeling is a useful approach to study the behavior of granular beds in solar rotary kilns. This technique, once validated with small-scale experiments, can be used to simulate large-scale processes for industrial applications. This study gives a comprehensive classification of numerical models used to simulate the movement and heat transfer for beds of granular media within solar rotary furnaces. In general, there exist three categories of models: 1) continuum, 2) discrete, and 3) multiphysics modeling. The continuum modeling considers zero-dimensional, one-dimensional and fluid-like models. On the other hand, the discrete element models compute the movement of each particle of the bed individually. In this kind of modeling, the heat transfer acts during contacts, which can occur by solid-solid and solid-gas-solid conduction. Finally, the multiphysics approach considers discrete elements to simulate grains and a continuous modeling to simulate the fluid around particles. This classification allows to compare the advantages and disadvantages for each kind of model in terms of accuracy, computational cost and implementation.Keywords: granular beds, numerical models, rotary kilns, solar thermal applications
Procedia PDF Downloads 342510 Decision Support System for the Management of the Shandong Peninsula, China
Authors: Natacha Fery, Guilherme L. Dalledonne, Xiangyang Zheng, Cheng Tang, Roberto Mayerle
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A Decision Support System (DSS) for supporting decision makers in the management of the Shandong Peninsula has been developed. Emphasis has been given to coastal protection, coastal cage aquaculture and harbors. The investigations were done in the framework of a joint research project funded by the German Ministry of Education and Research (BMBF) and the Chinese Academy of Sciences (CAS). In this paper, a description of the DSS, the development of its components, and results of its application are presented. The system integrates in-situ measurements, process-based models, and a database management system. Numerical models for the simulation of flow, waves, sediment transport and morphodynamics covering the entire Bohai Sea are set up based on the Delft3D modelling suite (Deltares). Calibration and validation of the models were realized based on the measurements of moored Acoustic Doppler Current Profilers (ADCP) and High Frequency (HF) radars. In order to enable cost-effective and scalable applications, a database management system was developed. It enhances information processing, data evaluation, and supports the generation of data products. Results of the application of the DSS to the management of coastal protection, coastal cage aquaculture and harbors are presented here. Model simulations covering the most severe storms observed during the last decades were carried out leading to an improved understanding of hydrodynamics and morphodynamics. Results helped in the identification of coastal stretches subjected to higher levels of energy and improved support for coastal protection measures.Keywords: coastal protection, decision support system, in-situ measurements, numerical modelling
Procedia PDF Downloads 1952509 A Study on the Use Intention of Smart Phone
Authors: Zhi-Zhong Chen, Jun-Hao Lu, Jr., Shih-Ying Chueh
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Based on Unified Theory of Acceptance and Use of Technology (UTAUT), the study investigates people’s intention on using smart phones. The study additionally incorporates two new variables: 'self-efficacy' and 'attitude toward using'. Samples are collected by questionnaire survey, in which 240 are valid. After Correlation Analysis, Reliability Test, ANOVA, t-test and Multiple Regression Analysis, the study finds that social impact and self-efficacy have positive effect on use intentions, and the use intentions also have positive effect on use behavior.Keywords: [1] Ajzen & Fishbein (1975), “Belief, attitude, intention and behavior: An introduction to theory and research”, Reading MA: Addison-Wesley. [2] Bandura (1977) Self-efficacy: toward a unifying theory of behavioural change. Psychological Review , 84, 191–215. [3] Bandura( 1986) A. Bandura, Social foundations of though and action, Prentice-Hall. Englewood Cliffs. [4] Ching-Hui Huang (2005). The effect of Regular Exercise on Elderly Optimism: The Self-efficacy and Theory of Reasoned Action Perspectives.(Master's dissertation, National Taiwan Sport University, 2005).National Digital Library of Theses and Dissertations in Taiwan。 [5] Chun-Mo Wu (2007).The Effects of Perceived Risk and Service Quality on Purchase Intention - an Example of Taipei City Long-Term Care Facilities. (Master's dissertation, Ming Chuan University, 2007).National Digital Library of Theses and Dissertations in Taiwan. [6] Compeau, D.R., and Higgins, C.A., (1995) “Application of social cognitive theory to training for computer skills.”, Information Systems Research, 6(2), pp.118-143. [7] computer-self-efficacy and mediators of the efficacy-performance relationship. International Journal of Human-Computer Studies, 62, 737-758. [8] Davis et al(1989), “User acceptance of computer technology: A comparison of two theoretical models ”, Management Science, 35(8), p.982-1003. [9] Davis et al(1989), “User acceptance of computer technology:A comparison of two theoretical models ”, Management Science, 35(8), p.982-1003. [10] Davis, F.D. (1989). Perceived Usefulness, Perceived Ease of Use and User Acceptance of Information Technology. MIS Quarterly, 13(3), 319-340。 [11] Davis. (1989). Perceived Usefulness, Perceived Ease of Use, and User Acceptance of Information Technology. MIS Quarterly, 13(3), 319–340. doi:10.2307/249008 [12] Johnson, R. D. (2005). An empirical investigation of sources of application-specific [13] Mei-yin Hsu (2010).The Study on Attitude and Satisfaction of Electronic Documents System for Administrators of Elementary Schools in Changhua County.(Master's dissertation , Feng Chia University, 2010).National Digital Library of Theses and Dissertations in Taiwan. [14] Ming-Chun Hsieh (2010). Research on Parents’ Attitudes Toward Electronic Toys: The case of Taichung City.(Master's dissertation, Chaoyang University of Technology,2010).National Digital Library of Theses and Dissertations in Taiwan. [15] Moon and Kim(2001). Extending the TAM for a World-Wide-Web context, Information and Management, v.38 n.4, p.217-230. [16] Shang-Yi Hu (2010).The Impacts of Knowledge Management on Customer Relationship Management – Enterprise Characteristicsand Corporate Governance as a Moderator.(Master's dissertation, Leader University, 2010)。National Digital Library of Theses and Dissertations in Taiwan. [17] Sheng-Yi Hung (2013, September10).Worldwide sale of smartphones to hit one billion IDC:Android dominate the market. ETtoday. Retrieved data form the available protocol:2013/10/3. [18] Thompson, R.L., Higgins, C.A., and Howell, J.M.(1991), “Personal Computing: Toward a Conceptual Model of Utilization”, MIS Quarterly(15:1), pp. 125-143. [19] Venkatesh, V., M.G. Morris, G.B. Davis, and F. D. Davis (2003), “User acceptance of information technology: Toward a unified view, ” MIS Quarterly, 27, No. 3, pp.425-478. [20] Vijayasarathy, L. R. (2004), Predicting Consumer Intentions to Use On-Line Shopping: The Case for an Augmented Technology Acceptance Model, Information and Management, Vol.41, No.6, pp.747-762. [21] Wikipedia - smartphone (http://zh.wikipedia.org/zh-tw/%E6%99%BA%E8%83%BD%E6%89%8B%E6%9C%BA)。 [22] Wu-Minsan (2008).The impacts of self-efficacy, social support on work adjustment with hearing impaired. (Master's dissertation, Southern Taiwan University of Science and Technology, 2008).National Digital Library of Theses and Dissertations in Taiwan. [23] Yu-min Lin (2006). The Influence of Business Employee’s MSN Self-efficacy On Instant Messaging Usage Behavior and Communicaiton Satisfaction.(Master's dissertation, National Taiwan University of Science and Technology, 2006).National Digital Library of Theses and Dissertations in Taiwan.
Procedia PDF Downloads 4102508 Unravelling Cross-Commodity Price Transmission Dynamics between Coastal and Freshwater Fish Species in Bangladesh: A Structural VAR Analysis
Authors: Farhana Arefeen Mila, Luis Emilio Morales, Nam Hoang, Sujana Adapa, Garry Griffith
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This study investigates the existence of price transmission asymmetries and imperfections among the coastal and freshwater fish species in Bangladesh. Using a Structural Vector Autoregression (SVAR) model, we explore how price changes in one fish species impact the prices of others in the retail market. Monthly data from the Department of Agricultural Marketing (DAM) covering the period from 2012 to 2023 was analyzed. Price series were detrended using the Hodrick-Prescott filter, and unit root tests confirmed stationarity after detrending. The findings indicate that there are significant interdependencies and asymmetries in price transmission, particularly the strong influence of Hilsha on the broader fish market. Hilsha’s price shocks generate immediate responses across other species, reflecting its cultural and economic importance. Silver Pomfret demonstrates some independence but is still affected by broader market fluctuations, particularly those involving Hilsha. Meanwhile, Rohu and Catla exhibit high interdependence, where price changes in one species closely impact the other, underscoring their substitutable nature in consumer preferences. These findings emphasize the need for joint interventions and market monitoring to stabilize prices effectively. Stakeholders are encouraged to monitor Hilsha’s market, consider coordinated interventions for Rohu and Catla, and establish data-sharing partnerships to enhance market stability. Additionally, promoting consumer awareness of price trends and sustainable practices can further support market resilience and long-term sustainability in the fisheries sector.Keywords: price transmission, cross commodity, fish, Bangladesh, CCF, SVAR, IRF
Procedia PDF Downloads 122507 Full-Scale 3D Simulation of the Electroslag Rapid Remelting Process
Authors: E. Karimi-Sibaki, A. Kharicha, M. Wu, A. Ludwig
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The standard electroslag remelting (ESR) process can ideally control the solidification of an ingot and produce homogeneous structure with minimum defects. However, the melt rate of electrode is rather low that makes the whole process uneconomical especially to produce small ingot sizes. In contrast, continuous casting is an economical process to produce small ingots such as billets at high casting speed. Unfortunately, deep liquid melt pool forms in the billet ingot of continuous casting that leads to center porosity and segregation. As such, continuous casting is not suitable to produce segregation prone alloys like tool steel or several super alloys. On the other hand, the electro slag rapid remelting (ESRR) process has advantages of both traditional ESR and continuous casting processes to produce billets. In the ESRR process, a T-shaped mold is used including a graphite ring that takes major amount of current through the mold. There are only a few reports available in the literature discussing about this topic. The research on the ESRR process is currently ongoing aiming to improve the design of the T-shaped mold, to decrease overall heat loss in the process, and to obtain a higher temperature at metal meniscus. In the present study, a 3D model is proposed to investigate the electromagnetic, thermal, and flow fields in the whole process as well as solidification of the billet ingot. We performed a fully coupled numerical simulation to explore the influence of the electromagnetically driven flow (MHD) on the thermal field in the slag and ingot. The main goal is to obtain some fundamental understanding of the formation of melt pool of the solidifying billet ingot in the ESRR process.Keywords: billet ingot, magnetohydrodynamics (mhd), numerical simulation, remelting, solidification, t-shaped mold.
Procedia PDF Downloads 2942506 Entrepreneurial Orientation and Innovation Outcomes in Ghanaian Social Enterprises: Interaction Effect of Organizational Unlearning
Authors: Stephen Oduro
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With a quantitative research design, this study seeks to analyze how, an intangible resource, Organisational Unlearning shapes the relationship between Entrepreneurial Orientation (EO) and Innovation Outcomes among social entrepreneurship organizations in Ghana. The Resource-Based View (RBV) of the firm and EO-Performance Contingency framework was adopted as the underpinning theories of the study. Entrepreneurial Orientation dimensions, namely Innovativeness, Autonomy, Risk-Taking, Proactiveness, and Competitive aggressiveness were examined to determine its significant, direct influence on the Innovation Outcomes of the social enterprises in Ghana. Organizational Unlearning dimensions, specifically examination of lens fitting, the consolidation of emergent understandings, and framework for changing individual habits were explored to determine whether they strengthen or weaken the direct nexus between Entrepreneurial Orientation dimensions and Innovation Outcomes. A self-administered questionnaire was administered to 556 targeted social enterprises across Africa through online questionnaire platform and the data generated and proposed hypotheses were analyzed and tested using Structural Equation Model-Partial Least Square (SEM-PLS 3) statistical tool. The findings revealed that EO dimensions, specifically proactiveness, autonomy, innovativeness, and risk-taking are positively related to IO, but we found no significant support for competitive aggressiveness. The findings, moreover, divulged that the positive, direct relationship between EO and IO is highly strengthened by OU. It is concluded that OU fully moderates the direct link between EO and IO. The present study contributes to the our understanding of the interrelationship among Entrepreneurial Orientation, Organizational Unlearning, and Innovation Outcomes in the social entrepreneurship context.Keywords: entrepreneurial orientation, innovation outcomes, organizational unlearning, RBV, SEM-PLS, social enterprise, Africa
Procedia PDF Downloads 1402505 Determination of Heavy Metal Levels in Carissa spinarum and Toddalia asiatica Used as Herbal Medicines in Kisii and Nyamira Counties Region, Kenya
Authors: Moses A. Guto Maobe, Leonard Gitu, Erastus Gatebe
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The plants Carissa spinarum and Toddalia asiatica have historically been used as herbal medicines in Kisii and Nyamira Counties region, Kenya. But, there is limited study about heavy metal contents in their different plant parts. Such information is necessary for proper use of the two plant species as herbal medicines. So, precise determination of heavy metal contents in different part of these herbs is required for quality, efficacy and safety use in the treatment of ailments. The main aim of this study was to standardize the two herbs of interest. The objective of this study was to evaluate the levels of heavy metal contents in the root of Carissa spinarum and Toddalia asiatica. A wet digestion method with concentrated nitric-hydrochloric acid was used for the dissolution of each herb part prior to elemental analysis. Standard solutions of various concentrations of each pure metal of analytical grade arsenic (As), cadmium (Cd) and mercury (Hg) were prepared and used. The analysis of As, Cd and Hg in each of two herbs was conducted by atomic absorption spectroscopy (AAS) Shimadzu model No. 6200. Data obtained from root of Carissa spinarum indicated concentration (mgkg⁻¹) of Arsenic (As), Cadmium (Cd) and Mercury (Hg) were 0.87 x 10⁻³, 7.02 x 10⁻⁶ and 0.66 x 10⁻³ respectively. Results obtained from root of Toddalia asiatica showed concentration (mgkg⁻¹) of Arsenic (As), Cadmium (Cd) and Mercury (Hg) were 1.33 x 10⁻³, 7.32 x 10⁻⁶ and 1.13 x 10⁻³, respectively. The permissible limits set by WHO for As, Cd and Hg in herbs are (mgkg⁻¹) < 1 - 5, < 0.3 – 1 and < 0.1- 0.5 respectively. The concentrations of As, Cd, and Hg determined were relatively higher in the root of Toddalia asiatica than the root of Carissa spinarum. It was concluded that levels of heavy metal contents of As, Cd, and Hg in the root of Carissa spinarum and Toddalia asiatica were within permissible limits set by WHO/FAO.Keywords: heavy metals, Carissa spinarum, Toddalia asiatica, wet digestion, pollutants, AAS
Procedia PDF Downloads 1682504 Modeling of Drug Distribution in the Human Vitreous
Authors: Judith Stein, Elfriede Friedmann
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The injection of a drug into the vitreous body for the treatment of retinal diseases like wet aged-related macular degeneration (AMD) is the most common medical intervention worldwide. We develop mathematical models for drug transport in the vitreous body of a human eye to analyse the impact of different rheological models of the vitreous on drug distribution. In addition to the convection diffusion equation characterizing the drug spreading, we use porous media modeling for the healthy vitreous with a dense collagen network and include the steady permeating flow of the aqueous humor described by Darcy's law driven by a pressure drop. Additionally, the vitreous body in a healthy human eye behaves like a viscoelastic gel through the collagen fibers suspended in the network of hyaluronic acid and acts as a drug depot for the treatment of retinal diseases. In a completely liquefied vitreous, we couple the drug diffusion with the classical Navier-Stokes flow equations. We prove the global existence and uniqueness of the weak solution of the developed initial-boundary value problem describing the drug distribution in the healthy vitreous considering the permeating aqueous humor flow in the realistic three-dimensional setting. In particular, for the drug diffusion equation, results from the literature are extended from homogeneous Dirichlet boundary conditions to our mixed boundary conditions that describe the eye with the Galerkin's method using Cauchy-Schwarz inequality and trace theorem. Because there is only a small effective drug concentration range and higher concentrations may be toxic, the ability to model the drug transport could improve the therapy by considering patient individual differences and give a better understanding of the physiological and pathological processes in the vitreous.Keywords: coupled PDE systems, drug diffusion, mixed boundary conditions, vitreous body
Procedia PDF Downloads 1372503 Eudesmane-Type Sesquiterpenes from Laggera alata Inhibiting Angiogenesis
Authors: Liang Ning, Chung Hau Yin
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Angiogenesis is the process of new blood vessel development. It has been recognized as a therapeutic target for blocking cancer growth four decades ago. Vascular sprouting is initiated by pro-angiogenic factors. Vascular endothelial cell growth factor (VEGF) plays a central role in angiogenic initiation, many patients with cancer or ocular neovascularization have been benefited from anti-VEGF therapy. Emerging approaches impacting in the later stages of vessel remodeling and maturation are expected to improve clinical efficacy. TIE receptor as well as the corresponding angiopoietin ligands, were identified as another endothelial cell specific receptor tyrosine kinase signaling system. Much efforts were made to reduce the activity of angiopoietin-TIE receptor axis. Two eudesmane-type sesquiterpenes from laggera alata, namely, 15-dihydrocostic acid and ilicic acid were found with strong anti-angiogenic properties in zebrafish model. Meanwhile, the mRNA expression levels of VEGFR2 and TIE2 pathway related genes were down-regulated in the sesquiterpenes treated zebrafish embryos. Besides, in human umbilical vein endothelial cells (HUVECs), the sesquiterpenes have the ability to inhibit VEGF-induced HUVECs proliferation and migration at non-toxic concentration. Moreover, angiopoietin-2 induced TIE2 phosphorylation was inhibited by the sesquiterpenes, the inhibitory effect was detected in angiopoietin-1 induced HUVECs proliferation as well. Thus, we hypothesized the anti-angiogenic activity of the compounds may via the inhibition of VEGF and TIE2 related pathways. How the compounds come into play as the pathways inhibitors need to be evaluated in the future.Keywords: Laggera alata, eudesmane-type sesquiterpene, anti-angiogenesis, VEGF, angiopoietin, TIE2
Procedia PDF Downloads 2102502 Impact of Map Generalization in Spatial Analysis
Authors: Lin Li, P. G. R. N. I. Pussella
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When representing spatial data and their attributes on different types of maps, the scale plays a key role in the process of map generalization. The process is consisted with two main operators such as selection and omission. Once some data were selected, they would undergo of several geometrical changing processes such as elimination, simplification, smoothing, exaggeration, displacement, aggregation and size reduction. As a result of these operations at different levels of data, the geometry of the spatial features such as length, sinuosity, orientation, perimeter and area would be altered. This would be worst in the case of preparation of small scale maps, since the cartographer has not enough space to represent all the features on the map. What the GIS users do is when they wanted to analyze a set of spatial data; they retrieve a data set and does the analysis part without considering very important characteristics such as the scale, the purpose of the map and the degree of generalization. Further, the GIS users use and compare different maps with different degrees of generalization. Sometimes, GIS users are going beyond the scale of the source map using zoom in facility and violate the basic cartographic rule 'it is not suitable to create a larger scale map using a smaller scale map'. In the study, the effect of map generalization for GIS analysis would be discussed as the main objective. It was used three digital maps with different scales such as 1:10000, 1:50000 and 1:250000 which were prepared by the Survey Department of Sri Lanka, the National Mapping Agency of Sri Lanka. It was used common features which were on above three maps and an overlay analysis was done by repeating the data with different combinations. Road data, River data and Land use data sets were used for the study. A simple model, to find the best place for a wild life park, was used to identify the effects. The results show remarkable effects on different degrees of generalization processes. It can see that different locations with different geometries were received as the outputs from this analysis. The study suggests that there should be reasonable methods to overcome this effect. It can be recommended that, as a solution, it would be very reasonable to take all the data sets into a common scale and do the analysis part.Keywords: generalization, GIS, scales, spatial analysis
Procedia PDF Downloads 3282501 Parametric Study of 3D Micro-Fin Tubes on Heat Transfer and Friction Factor
Authors: Shima Soleimani, Steven Eckels
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One area of special importance for surface-level study of heat exchangers is tubes with internal micro-fins (< 0.5 mm tall). Micro-finned surfaces are a kind of extended solid surface in which energy is exchanged with water that acts as the source or sink of energy. Significant performance gains are possible for either shell, tube, or double pipe heat exchangers if the best surfaces are identified. The parametric studies of micro-finned tubes that have appeared in the literature left some key parameters unexplored. Specifically, they ignored three-dimensional (3D) micro-fin configurations, conduction heat transfer in the fins, and conduction in the solid surface below the micro-fins. Thus, this study aimed at implementing a parametric study of 3D micro-finned tubes that considered micro-fin height and discontinuity features. A 3D conductive and convective heat-transfer simulation through coupled solid and periodic fluid domains is applied in a commercial package, ANSYS Fluent 19.1. The simulation is steady-state with turbulent water flow cooling inner wall of a tube with micro-fins. The simulation utilizes a constant and uniform temperature on the tube outer wall. Performance is mapped for 18 different simulation cases, including a smooth tube using a realizable k-ε turbulence model at a Reynolds number of 48,928. Results compared the performance of 3D tubes with results for the similar two-dimensional (2D) one. Results showed that the micro-fin height has greater impact on performance factor than discontinuity features in 3D micro-fin tubes. A transformed 3D micro-fin tube can enhance heat transfer and pressure drop up to 21% and 56% compared to a 2D one, respectfully.Keywords: three-dimensional micro-finned tube, heat transfer, friction factor, heat exchanger
Procedia PDF Downloads 1152500 Intercultural Sensitivity in Iran: A Case Study of Intercultural Relations between Turks and Lors
Authors: Sepideh Mohammadi
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Iran is a country that boasts of ethnic diversity, comprising various groups such as Turks, Lors, Arabs, Baluchs, Persians, Kurds, Gliks, Azaris, and Tabaris. The majority of people in Iran are Persians and as such, the Persian language is the official language of the country. However, it is also a common language among different ethnic groups. It is worth noting that there is a longstanding history of coexistence and cultural relations between the Turkic and Lor ethnic groups. The purpose of this article is to study the range of intercultural sensitivities of Turks and Lor peoples to identify the state of intercultural competence and reduce conflicts in the direction of cultural policy. It is important to gain insight into the mutual perceptions of Lor and Turkic people towards each other. Understanding these perceptions can greatly aid in fostering stronger relationships and promoting effective communication between the two ethnic groups. The study employed a qualitative content analysis approach to gather data using a semi-structured interview tool. The participants consisted of ten individuals from the Lor ethnic and ten individuals from the Turk ethnic. According to Milton Bennett's six-stage model, our findings reveal that the Turkish and Lor ethnic groups tend to exhibit higher intercultural sensitivity in the second stage, which consists of defense against differences. Both groups tend to emphasize the differences between them, and the notion of "us and the other" holds significant importance for them. It is important to acknowledge that both the Turk and Lor ethnicities consist of various clans, which significantly shape intercultural relations between them. A common stereotype in this regard is that the Turks of Tabriz province often do not recognize the Turks of other provinces of the country as their own. Moreover, our study indicates that an increase in interaction and communication between the Lor and Turk ethnic groups may lead to a reduction in cultural sensitivities between them.Keywords: intercultural communication, intercultural sensitivity, Iran, Lor, Turk
Procedia PDF Downloads 472499 Photocatalytic Degradation of Methylene Blue Dye Using Cuprous Oxide/Graphene Nanocomposite
Authors: Bekan Bogale, Tsegaye Girma Asere, Tilahun Yai, Fekadu Melak
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Aims: To study photocatalytic degradation of methylene blue dye on cuprous oxide/graphene nanocomposite. Background: Cuprous oxide (Cu2O) nanoparticles are among the metal oxides that demonstrated photocatalytic activity. However, the stability of Cu2O nanoparticles due to the fast recombination rate of electron/hole pairs remains a significant challenge in their photocatalytic applications. This, in turn, leads to mismatching of the effective bandgap separation, tending to reduce the photocatalytic activity of the desired organic waste (MB). To overcome these limitations, graphene has been combined with cuprous oxides, resulting in cuprous oxide/graphene nanocomposite as a promising photocatalyst. Objective: In this study, Cu2O/graphene nanocomposite was synthesized and evaluated for its photocatalytic performance of methylene blue (MB) dye degradation. Method: Cu2O/graphene nanocomposites were synthesized from graphite powder and copper nitrate using the facile sol-gel method. Batch experiments have been conducted to assess the applications of the nanocomposites for MB degradation. Parameters such as contact time, catalyst dosage, and pH of the solution were optimized for maximum MB degradation. The prepared nanocomposites were characterized by using UV-Vis, FTIR, XRD, and SEM. The photocatalytic performance of Cu2O/graphene nanocomposites was compared against Cu2O nanoparticles for cationic MB dye degradation. Results: Cu2O/graphene nanocomposite exhibits higher photocatalytic activity for MB degradation (with a degradation efficiency of 94%) than pure Cu2O nanoparticles (67%). This has been accomplished after 180 min of irradiation under visible light. The kinetics of MB degradation by Cu2O/graphene composites can be demonstrated by the second-order kinetic model. The synthesized nanocomposite can be used for more than three cycles of photocatalytic MB degradation. Conclusion: This work indicated new insights into Cu2O/graphene nanocomposite as high-performance in photocatalysis to degrade MB, playing a great role in environmental protection in relation to MB dye.Keywords: methylene blue, photocatalysis, cuprous oxide, graphene nanocomposite
Procedia PDF Downloads 1892498 Asset Pricing Puzzle and GDP-Growth: Pre and Post Covid-19 Pandemic Effect on Pakistan Stock Exchange
Authors: Mohammad Azam
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This work is an endeavor to empirically investigate the Gross Domestic Product-Growth as mediating variable between various factors and portfolio returns using a broad sample of 522 financial and non-financial firms enlisted on Pakistan Stock Exchange between January-1993 and June-2022. The study employs the Structural Equation modeling and Ordinary Least Square regression to determine the findings before and during the Covid-19 epidemiological situation, which has not received due attention by researchers. The analysis reveals that market and investment factors are redundant, whereas size and value show significant results, whereas Gross Domestic Product-Growth performs significant mediating impact for the whole time frame. Using before Covid-19 period, the results reveal that market, value, and investment are redundant, but size, profitability, and Gross Domestic Product-Growth are significant. During the Covid-19, the statistics indicate that market and investment are redundant, though size and Gross Domestic Product-Growth are highly significant, but value and profitability are moderately significant. The Ordinary Least Square regression shows that market and investment are statistically insignificant, whereas size is highly significant but value and profitability are marginally significant. Using the Gross Domestic Product-Growth augmented model, a slight growth in R-square is observed. The size, value and profitability factors are recommended to the investors for Pakistan Stock Exchange. Conclusively, in the Pakistani market, the Gross Domestic Product-Growth indicates a feeble moderating effect between risk-premia and portfolio returns.Keywords: asset pricing puzzle, mediating role of GDP-growth, structural equation modeling, COVID-19 pandemic, Pakistan stock exchange
Procedia PDF Downloads 732497 Self-reported Acute Pesticide Intoxication in Ethiopia
Authors: Amare Nigatu, Mågne Bratveit, Bente E. Moen
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Background: Pesticide exposure is an important public health concern in Ethiopia, but there is limited information on pesticide intoxications. Residents may have an increased risk of pesticide exposure through proximity of their homes to farms using pesticides. Also the pesticide exposure might be related to employment at these farms. This study investigated the prevalence of acute pesticide intoxications (API) by residence proximity to a nearby flower farm and assessed if intoxications are related to working there or not. Methods: A cross-sectional survey involving 516 persons was conducted. Participants were grouped according to their residence proximity from a large flower farm; living within 5 kilometers and 5-12 kilometers away, respectively. In a structured interview, participants were asked if they had health symptoms within 48 hours of pesticide exposure in the past year. Those, who had experienced this and reported two or more typical pesticide intoxication symptoms, were considered as having had API. Chi-square and independent t-tests were used to compare categorical and continuous variables, respectively. Confounding variables were adjusted by using binomial regression model. Results: The prevalence of API in the past year among the residents in the study area was 26%, and it was higher in the population living close to the flower farm (42%) compared to those living far away (11%), prevalence ratio (PR) = 3.2, 95% CI: 2.2-4.8, adjusted for age, gender & education. A subgroup living close to the farm & working there had significantly more API (56%) than those living close & did not work there (16%), adjusted PR = 3.0, 95% CI: 1.8-4.9. Flower farm workers reported more API (56%) than those not working there (13%,), adjusted PR = 4.0, 95% CI: 2.9-5.6. Conclusion: The residents living closer than 5 kilometers to the flower farm reported significantly higher prevalence of API than those living 5-12 kilometers away. This increased risk of API was associated with work at the flower farm.Keywords: acute pesticide intoxications, self-reported symptoms, flower farm workers, living proximity
Procedia PDF Downloads 2922496 Communication Infrastructure Required for a Driver Behaviour Monitoring System, ‘SiaMOTO’ IT Platform
Authors: Dogaru-Ulieru Valentin, Sălișteanu Ioan Corneliu, Ardeleanu Mihăiță Nicolae, Broscăreanu Ștefan, Sălișteanu Bogdan, Mihai Mihail
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The SiaMOTO system is a communications and data processing platform for vehicle traffic. The human factor is the most important factor in the generation of this data, as the driver is the one who dictates the trajectory of the vehicle. Like any trajectory, specific parameters refer to position, speed and acceleration. Constant knowledge of these parameters allows complex analyses. Roadways allow many vehicles to travel through their confined space, and the overlapping trajectories of several vehicles increase the likelihood of collision events, known as road accidents. Any such event has causes that lead to its occurrence, so the conditions for its occurrence are known. The human factor is predominant in deciding the trajectory parameters of the vehicle on the road, so monitoring it by knowing the events reported by the DiaMOTO device over time, will generate a guide to target any potentially high-risk driving behavior and reward those who control the driving phenomenon well. In this paper, we have focused on detailing the communication infrastructure of the DiaMOTO device with the traffic data collection server, the infrastructure through which the database that will be used for complex AI/DLM analysis is built. The central element of this description is the data string in CODEC-8 format sent by the DiaMOTO device to the SiaMOTO collection server database. The data presented are specific to a functional infrastructure implemented in an experimental model stage, by installing on a number of 50 vehicles DiaMOTO unique code devices, integrating ADAS and GPS functions, through which vehicle trajectories can be monitored 24 hours a day.Keywords: DiaMOTO, Codec-8, ADAS, GPS, driver monitoring
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