Search results for: important bird area
5676 Slow and Controlled Release Fertilizer Technology via Application of Plant-available Inorganic Coatings
Authors: Eugene Rybin
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Reduction of nutrient losses when using mineral fertilizers is a very important and urgent challenge, which is of both economic and environmental significance. This paper shows the production of slow- and controlled release fertilizers through application of inorganic coatings, which make the released nutrients plant-available. The method of production of coated fertilizers with inorganic cover material is an alternative to other methods where polymer coatings are used. The method is based on spraying an aqueous slurry onto the surface of granules with simultaneous drying in drums under certain conditions and subsequent cooling of granules. This method of production of slow- and controlled-release fertilizers is more ecofriendly compared with others because inorganic materials are used to create a membrane. That is why the coating material is definitely biodegradable. There is also shown the effect of these coatings on the properties of fertilizers, as well as on the agrochemical efficiency and nutrient efficiency/ availability to the plants. The agrochemical tests have proved the increase of nutrient efficiency for every nutrient in compound fertilizers (NPK, NPS) for 3 consecutive years by 10-20 % and by 25-28% for urea, as well as an increase in crop yield, by 10-15% in general, and its quality. Moreover, the decrease in caking by almost 70% was proven as well as slowing down the release rate of nutrients from fertilizers. Control of the release rate was achieved by regulation of thickness and contents of coating materials. All of those characteristics were researched according to the standard-used methods. The performed research has developed the fertilizer technology of slow- and controlled release of nutrients through applying of plant-available inorganic coatings. It leads to a better synchronization of nutrient release rate and plants needs, as well as reduces the harmful effects on the environment from the fertilizers applied.Keywords: controlled release, fertilizers, nutrients, plant-available coatings
Procedia PDF Downloads 885675 Analysis of Coloring Styles of Brazilian Urban Heritage
Authors: Natalia Naoumova
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Facing changes and continuous growth of the contemporary cities, along with the globalization effects that accelerate cultural dissolution, the maintenance of cultural authenticity, which is implicit in historical areas as a part of cultural diversity, can be considered one of the key elements of a sustainable society. This article focuses on the polychromy of buildings in a historical context as an important feature of urban settings. It analyses the coloring of Brazilian urban heritage, characterized by the study of historical districts in Pelotas and Piratini, located in the State of Rio Grande do Sul, Brazil. The objective is to reveal the coloring characteristics of different historical periods, determine the chromatic typologies of the corresponding building styles, and clarify the connection between the historical chromatic aspects and their relationship with the contemporary urban identity. Architectural style data were collected by different techniques such as stratigraphic prospects of buildings, survey of historical records and descriptions, analysis of images and study of projects with colored facades kept in historical archives. Three groups of characteristics were considered in searching for working criteria in the formation of chromatic model typologies: 1) coloring palette; 2) morphology of the facade, and 3) their relationship. The performed analysis shows the formation of the urban chromatic image of the historical center as a continuous and dynamic process with the development of constant chromatic resources. It establishes that the changes in the formal language of subsequent historical periods lead to the changes in the chromatic schemes, providing a different reading of the facades both in terms of formal interpretation and symbolic meaning.Keywords: building style, historic colors, urban heritage, urban polychromy
Procedia PDF Downloads 1325674 Analysis of Hotel Websites to Attract Tourists in Iran, Case Study: Yazd City
Authors: Leila Habibi, Hadi Hakimi, Maryam Jafari Mehrabadi, Hadi Sadeghian
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Nowadays, the importance of information technology and web- based information in tourism is very obvious. Increasing of sales and promotion of brands, the rise of information about tourist attractions and tourist areas, Entrepreneurship and making money, introducing of hotels and side information to tourists via web are some Examples of website effects on tourism. The hotels using web-based information can succeed in attracting tourists and improve the quality of services to the tourists so; the study of hotel websites has become one of the most important issues in tourism. Therefore, this research aims to analyze the status of hotel websites in Yazd City as one of the most tourist visited counties in Iran. The quality of hotel website in a city such as this city can be very vital for tourism. Hence, this research compares the status of hotel websites in Yazd City with standard indexes and items that extracted from Literature and theoretical framework. It is used content analysis for analyzing of hotel websites with indexes and items in methodology. In the other words, all of the items is compared with the content of hotel-websites in Yazd one by one. Finally, every hotel archived final score and it represents the position of the hotel among the others. All of scores and status of hotels is displayed in their own Figures. The result of this research shows that many hotels do not offer standard web -based services and information. So, the existing situation is not very suitable for the attraction of web users or improving the tourism. The result of this research may help the managers and authorities of tourism to offer and improve the web- based services and information.Keywords: e-tourism, hotel websites, tourism, web-tourism
Procedia PDF Downloads 2875673 Integrated Free Space Optical Communication and Optical Sensor Network System with Artificial Intelligence Techniques
Authors: Yibeltal Chanie Manie, Zebider Asire Munyelet
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5G and 6G technology offers enhanced quality of service with high data transmission rates, which necessitates the implementation of the Internet of Things (IoT) in 5G/6G architecture. In this paper, we proposed the integration of free space optical communication (FSO) with fiber sensor networks for IoT applications. Recently, free-space optical communications (FSO) are gaining popularity as an effective alternative technology to the limited availability of radio frequency (RF) spectrum. FSO is gaining popularity due to flexibility, high achievable optical bandwidth, and low power consumption in several applications of communications, such as disaster recovery, last-mile connectivity, drones, surveillance, backhaul, and satellite communications. Hence, high-speed FSO is an optimal choice for wireless networks to satisfy the full potential of 5G/6G technology, offering 100 Gbit/s or more speed in IoT applications. Moreover, machine learning must be integrated into the design, planning, and optimization of future optical wireless communication networks in order to actualize this vision of intelligent processing and operation. In addition, fiber sensors are important to achieve real-time, accurate, and smart monitoring in IoT applications. Moreover, we proposed deep learning techniques to estimate the strain changes and peak wavelength of multiple Fiber Bragg grating (FBG) sensors using only the spectrum of FBGs obtained from the real experiment.Keywords: optical sensor, artificial Intelligence, Internet of Things, free-space optics
Procedia PDF Downloads 535672 An Electromyographic Study of Muscle Coordination during Dynamic Glenohumeral Joint Elevation
Authors: Omid Khaiyat, David Hawkes
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Introduction: There remains a lack of information on sophisticated coordination patterns across shoulder girdle muscles. Considering the stability of the shoulder being heavily dependent on coordinated muscle activity during its wide-ranging movements, it is important that key intermuscular relationships are well-defined for a better understanding of underlying pathology. This study investigated shoulder intermuscular coordination during different planes of shoulder elevation. Materials and Methods: EMG was recorded from 14 shoulder muscles in 20 healthy participants during shoulder flexion, scapula plane elevation, abduction, and extension. Cross-correlation by means of Pearson Correlation Coefficient (PCC) was used to examine the coordination between different muscles and muscle groups. Results: Coordination between rotator cuff and deltoid muscle groups was significantly higher (p =0.020-0.035) during the initial (PCC) = 0.79) and final (PCC = 0.74) phases of elevation compared to the mid-range (PCC = 0.34). Furthermore, a high level of coordination (PCC = 0.89) was noted between the deltoid group and the adductor group (latissimus dorsi and teres major) during the initial stage of shoulder elevation. Conclusion: The destabilising force of the deltoid during the initial stage of shoulder elevation is balanced by coordinated activity of rotator cuff, latissimus dorsi, and teres major. This is also the case for the end-range of movement, where increased demand for stability again leads to higher coordination between the deltoid and rotator cuff muscle groups. Appreciation of the sophistication of normal shoulder function evidence-based rehabilitation strategies for conditions such as subacromial impingement syndrome or shoulder instability can be developed.Keywords: shoulder, coordination, EMG, muscle activity, upper limb
Procedia PDF Downloads 1595671 A Review of Atomization Mechanisms Used for Spray Flash Evaporation: Their Effectiveness and Proposal of Rotary Bell Atomizer for Flashing Application
Authors: Murad A. Channa, Mehdi Khiadani. Yasir Al-Abdeli
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Considering the severity of water scarcity around the world and its widening at an alarming rate, practical improvements in desalination techniques need to be engineered at the earliest. Atomization is the major aspect of flashing phenomena, yet it has been paid less attention to until now. There is a need to test efficient ways of atomization for the flashing process. Flash evaporation together with reverse osmosis is also a commercially matured desalination technique commonly famous as Multi-stage Flash (MSF). Even though reverse osmosis is massively practical, it is not economical or sustainable compared to flash evaporation. However, flashing evaporation has its drawbacks as well such as lower efficiency of water production per higher consumption of power and time. Flash evaporation is simply the instant boiling of a subcooled liquid which is introduced as droplets in a well-maintained negative environment. This negative pressure inside the vacuum increases the temperature of the liquid droplets far above their boiling point, which results in the release of latent heat, and the liquid droplets turn into vapor which is collected to be condensed back into an impurity-free liquid in a condenser. Atomization is the main difference between pool and spray flash evaporation. Atomization is the heart of the flash evaporation process as it increases the evaporating surface area per drop atomized. Atomization can be categorized into many levels depending on its drop size, which again becomes crucial for increasing the droplet density (drop count) per given flow rate. This review comprehensively summarizes the selective results relating to the methods of atomization and their effectiveness on the evaporation rate from earlier works to date. In addition, the reviewers propose using centrifugal atomization for the flashing application, which brings several advantages viz ultra-fine droplets, uniform droplet density, and the swirling geometry of the spray with kinetically more energetic sprays during their flight. Finally, several challenges of using rotary bell atomizer (RBA) and RBA Sprays inside the chamber have been identified which will be explored in detail. A schematic of rotary bell atomizer (RBA) integration with the chamber has been designed. This powerful centrifugal atomization has the potential to increase potable water production in commercial multi-stage flash evaporators, where it would be preferably advantageous.Keywords: atomization, desalination, flash evaporation, rotary bell atomizer
Procedia PDF Downloads 735670 Usage of Biosorbent Material for the Removal of Nitrate from Wastewater
Authors: M. Abouleish, R. Umer, Z. Sara
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Nitrate can cause serious environmental and human health problems. Effluent from different industries and excessive use of fertilizers have increased the level of nitrate in ground and surface water. Nitrate can convert to nitrite in the body, and as a result, can lead to Methemoglobinemia and cancer. Therefore, different organizations have set standard limits for nitrate and nitrite. The United States Environmental Protection Agency (USEPA) has set a Maximum Contaminant Level Goal (MCLG) of 10 mg N/L for nitrate and 1 mg N/L for nitrite. The removal of nitrate from water and wastewater is very important to ensure the availability of clean water. Different plant materials such as banana peel, rice hull, coconut and bamboo shells, have been studied as biosorbents for the removal of nitrates from water. The use of abundantly existing plant material as an adsorbent material and the lack of energy requirement for the adsorption process makes biosorption a sustainable approach. Therefore, in this research, the fruit of the plant was investigated for its ability to act as a biosorbent to remove the nitrate from wastewater. The effect of pH on nitrate removal was studied using both the raw and chemically activated fruit (adsorbent). Results demonstrated that the adsorbent needs to be chemically activated before usage to remove the nitrate from wastewater. pH did not have a significant effect on the adsorption process, with maximum adsorption of nitrate occurring at pH 4. SEM/EDX results demonstrated that there is no change in the surface of the adsorbent as a result of the chemical activation. Chemical activation of the adsorbent using NaOH increased the removal of nitrate by 6%; therefore, various methods of activation of the adsorbent will be investigated to increase the removal of nitrate.Keywords: biosorption, nitrates, plant material, water, and wastewater treatment
Procedia PDF Downloads 1445669 The Effect of Grading Characteristics on the Shear Strength and Mechanical Behavior of Granular Classes of Sand-Silt
Authors: Youssouf Benmeriem
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Shear strength of sandy soils has been considered as the important parameter to study the stability of different civil engineering structures when subjected to monotonic, cyclic and earthquake loading conditions. The proposed research investigated the effect of grading characteristics on the shear strength and mechanical behavior of granular classes of sands mixed with silt in loose and dense states (Dr = 15% and 90%). The laboratory investigation aimed at understanding the extent or degree at which shear strength of sand-silt mixture soil is affected by its gradation under static loading conditions. For the purpose of clarifying and evaluating the shear strength characteristics of sandy soils, a series of Casagrande shear box tests were carried out on different reconstituted samples of sand-silt mixtures with various gradations. The soil samples were tested under different normal stresses (100, 200 and 300 kPa). The results from this laboratory investigation were used to develop insight into the shear strength response of sand and sand-silt mixtures under monotonic loading conditions. The analysis of the obtained data revealed that the grading characteristics (D10, D50, Cu, ESR, and MGSR) have significant influence on the shear strength response. It was found that shear strength can be correlated to the grading characteristics for the sand-silt mixture. The effective size ratio (ESR) and mean grain size ratio (MGSR) appear as pertinent parameters to predict the shear strength response of the sand-silt mixtures for soil gradation under study.Keywords: grading characteristics, granular classes of sands, mechanical behavior, sand-silt, shear strength
Procedia PDF Downloads 3785668 Personality Traits and Physical Activity among Staff Personnel of University of Southern Mindanao
Authors: Cheeze Janito, Crisly Dawang
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It is important to determine the personality traits that exist in the workplace and the contribution of these personality traits in the staff’s daily work routines; a sedentary lifestyle is harmful to one’s health. This study reports the personality traits of the University of Southern Mindanao, Kabacan, Philippines, non-teaching staff, the physical activity involvement of the non-teaching staff, and the big five personality traits that shape the relationship of university non-teaching staff in engaging physical activities. A quantitative method approach, which comprised a three-part questionnaire, was used to collect the data. The fifty non-teaching staff complete the survey. The results revealed that among the big five personality traits, the university non-teaching staff scored higher in agreeableness as revealed, that there was a commonality among the respondents’ traits of consideration to the feelings of the co-workers in observance to not being rude and vividly display of respect to co-workers and workplace and scored least in the personality trait of neuroticism. The study also reported that the university non-teaching staff's main physical activity was house chores as a prime physical exercise in which respondents reported a physical activity frequency of once to twice a week; thus, this study reported that the respondents are less engaged in doing physical activities. Further, the relationship of personality traits and the physical activity of the non-teaching staff gained a p-value of .596 that indicates there is no significant relationship between the two variables, the personality trait and physical activities. This study recommends the tight promotion of staff in engaging in physical activity of at least one hundred fifty minutes of moderate-intensity activity each week. Added to this, the use of different platforms containing physical exercise literacy and the benefits of physical exercise for the holistic development of the university community.Keywords: university staff, physical fitness, personality traits, physical activity
Procedia PDF Downloads 1835667 Evaluating and Prioritizing the Effective Management Factors of Human Resources Empowerment and Efficiency in Manufacturing Companies: A Case Study of Fars’ Livestock and Poultry Manufacturing Companies
Authors: Mohsen Yaghmoor, Sima Radmanesh
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Rapid environmental changes have been threaten the life of many organizations .Enabling and productivity of human resource should be considered as the most important issue in order to increase performance and ensure survival of the organizations. In this research, the effectiveness of management factory in productivity & inability of human resource have been identified and reviewed at glance. Afterward there were two questions they are “what are the factors effecting productivity and enabling of human resource” . And ”what are the priority order based on effective management of human resource in Fars Poultry Complex". A specified questionnaire has been designed in order to priorities and effectiveness of the identified factors. Six factors specify to consist of: Individual characteristics, teaching, motivation, partnership management, authority or power submission and job development that have most effect on organization. Then specify a questionnaire for priority and effect measurement of specified factor that reach after collect information and using statistical tests of keronchbakh alpha coefficient r=0.792 that we can say the questionnaire has sufficient reliability. After information analysis of specified six factors by Friedman test categorize their effect. Measurement on organization respectively consists of individual characteristics, job development or enrichment, authority submission, partnership management, teaching and motivation. At last it has been indicated to approaches to increase making power full and productivity of manpower.Keywords: productivity, empowerment, enrichment, authority submission, partnership management, teaching, motivation
Procedia PDF Downloads 2415666 The Effect of Family SES (Income) On Children’s Socio-Emotional Development
Authors: Xiao Hu
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Children’s social and emotional development is critical for developing their future relationships and behaviors, and poor social skills may result in serious emotional externalizations such as anxiety, distress and aggression. Recent research has emphasized the role of family socio-economic status on children’s emotional development, and this study contributes to this academic discussion by reviewing how socio-economic status affects children at three critical development stages: infancy (0-3months), pre-school (4 months-5 years) and school aged (6-10 years). Results show a consensus in the research literature on a positive relationship between family socio-economic status and children’s emotional development. Socialization, a crucial development milestone, is highly affected by a family’s socio-economic status, as families with higher incomes have access to improved social environments, healthier parenting styles and greater access to social capital and peer support. In contrast, families with lower income and SES (socio-economic status) have lower access to these benefits and are frequently ignored within social environments. This review concludes with a critical discussion on how family income affects children’s social environment, highlighting the important role that “permanent” income plays in children’s development. Consequently, the review suggests that future governments should provide temporary economic support for lower-income families, allowing children to be raised in a healthy social environment with limited economic fluctuation.Keywords: family socio-economic status, parenting style, children’s emotional development, family permanent income
Procedia PDF Downloads 1365665 Time to CT in Major Trauma in Coffs Harbour Health Campus - The Australian Rural Centre Experience
Authors: Thampi Rawther, Jack Cecire, Andrew Sutherland
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Introduction: CT facilitates the diagnosis of potentially life-threatening injuries and facilitates early management. There is evidence that reduced CT acquisition time reduces mortality and length of hospital stay. Currently, there are variable recommendations for ideal timing. Indeed, the NHS standard contract for a major trauma service and STAG both recommend immediate access to CT within a maximum time of 60min and appropriate reporting within 60min of the scan. At Coffs Harbour Health Campus (CHHC), a CT radiographer is on site between 8am-11pm. Aim: To investigate the average time to CT at CHHC and assess for any significant relationship between time to CT and injury severity score (ISS) or time of triage. Method: All major trauma calls between Jan 2021-Oct 2021 were audited (N=87). Patients were excluded if they went from ED to the theatre. Time to CT is defined as the time between triage to the timestamp on the first CT image. Median and interquartile range was used as a measure of central tendency as the data was not normally distributed, and Chi-square test was used to determine association. Results: The median time to CT is 51.5min (IQR 40-74). We found no relationship between time to CT and ISS (P=0.18) and time of triage to time to CT (P=0.35). We compared this to other centres such as John Hunter Hospital and Gold Coast Hospital. We found that the median CT acquisition times were 76min (IQR 52-115) and 43min, respectively. Conclusion: This shows an avenue for improvement given 35% of CT’s were >30min. Furthermore, being proactive and aware of time to CT as an important factor to trauma management can be another avenue for improvement. Based on this, we will re-audit in 12-24months to assess if any improvement has been made.Keywords: imaging, rural surgery, trauma surgery, improvement
Procedia PDF Downloads 975664 Assessing Solid Waste Management Practices in Port Harcourt City, Nigeria
Authors: Perpetual Onyejelem, Kenichi Matsui
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Solid waste management is one essential area for urban administration to achieve environmental sustainability. Proper solid waste management (SWM) improves the environment by reducing diseases and increasing public health. On the other way, improper SWM practices negatively impact public health and environmental sustainability. This article evaluates SWM in Port Harcourt, Nigeria, with the goal of determining the current solid waste management practices and their health implications. This study used secondary data, which relies on existing published literature and official documents. The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement and its four-stage inclusion/exclusion criteria were utilized as part of a systematic literature review technique to locate the literature that concerns SWM practices and the implementation of solid waste management policies between 2014-2023 in PortHarcourt and its health effects from specific databases (Scopus and Google Scholar). The results found that despite the existence and implementation of the Rivers State Waste Management Policy and the formulation of the National Policy on Solid Waste Management in Port Harcourt, residents continued to dump waste in drainages. They were unaware of waste sorting and dumped waste haphazardly. This trend has persisted due to a lack of political commitment to the effective implementation and monitoring of policies and strategies and a lack of training provided to waste collectors regarding the SWM approach, which involves sorting and separating waste. In addition, inadequate remuneration for waste collectors, the absence of community participation in policy formulation, and insufficient awareness among residents regarding the 3R approach are also contributory factors. This caused the emergence of vector-borne diseases such as malaria, lassa fever, and cholera in Port Harcourt, increasing the expense of healthcare for locals, particularly low-income households. The study urges the government to prioritize protecting the health of its citizens by studying the methods other nations have taken to address the problem of solid waste management and adopting those that work best for their region. The bottom-up strategy should be used to include locals in developing solutions. However, citizens who are always the most impacted by this issue should launch initiatives to address it and put pressure on the government to assist them when they have limitations.Keywords: health effects, solid waste management practices, environmental pollution, Port-Harcourt
Procedia PDF Downloads 545663 Evaluation of Raw Diatomaceous Earth and Plant Powders in the Control of Callosobruchus subinnotatus (Pic.) on Stored Bambara Groundnut (Vigna subterranea (L.) (Verdc.) Seeds
Authors: Ibrahim Nasiru Dole, Audu Abdullahi, Dike Michiel Chidozie, Lawal Mansur
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Bambara groundnut is an important grain legume and the seeds in storage suffer infestation by Callosobruchus subinnotatus. Laboratory study was conducted to evaluate the efficacy of raw diatomaceous earth (RDE) and plant powders (Jatropha curcas (L.), Eucalyptus camaldulensis (Dehnh.) and Melia azedarach (L.) against C. subinnotatus infesting stored bambara groundnut seeds. Rearing of the insects and the experiments were conducted in Agricultural Biology Laboratory of the Usmanu Danfodiyo University, Sokoto - Nigeria under ambient conditions (29-33oC and a relative humidity of 44-56%). Four treatments at three levels: RDE at 0.5, 1.0 and 1.5 g while plant powders at 0.5, 1.0 and 2.0 g, standard/check (2.0 g of Actellic dust), and a control. These were separately admixed with 100 g of sterilized seeds in glass jars. Each jar was later infested with thirty, 1-2-days old C. subinnotatus of mixed sexes. Adult mortality was assessed 24, 48, 72 and 96 hours, F1 and F2 progenies, seed damage, weight loss and viability were also assessed after 90 days. Eighty-nine (89%) percent adult mortality was recorded in the highest dose of RDE after 96 hours of exposure. These treatments significantly (P < 0.05) suppressed F1 and F2 progenies emergence in relation to the control. The control suffered significantly (P < 0.05) higher seed damage (51.0 %) and weight loss (40.8%) thereby recording lower seed germination. Therefore, RDE and plant powders could be used against C. subinnotatus on stored bambara groundnut seeds.Keywords: bambara, callosobruchus subinnotatus, plant powders, raw diatomaceous earth,
Procedia PDF Downloads 4185662 Human Trafficking the Kosovar Perspective of Fighting the Phenomena through Police and Civil Society Cooperation
Authors: Samedin Mehmeti
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The rationale behind this study is considering combating and preventing the phenomenon of trafficking in human beings from a multidisciplinary perspective that involves many layers of the society. Trafficking in human beings is an abhorrent phenomenon highly affecting negatively the victims and their families in both human and material aspect, sometimes causing irreversible damages. The longer term effects of this phenomenon, in countries with a weak economic development and extremely young and dynamic population, such as Kosovo, without proper measures to prevented and control can cause tremendous damages in the society. Given the fact that a complete eradication of this phenomenon is almost impossible, efforts should be concentrated at least on the prevention and controlling aspects. Treating trafficking in human beings based on traditional police tactics, methods and proceedings cannot bring satisfactory results. There is no doubt that a multi-disciplinary approach is an irreplaceable requirement, in other words, a combination of authentic and functional proactive and reactive methods, techniques and tactics. Obviously, police must exercise its role in preventing and combating trafficking in human beings, a role sanctioned by the law, however, police role and contribution cannot by any means considered complete if all segments of the society are not included in these efforts. Naturally, civil society should have an important share in these collaborative and interactive efforts especially in preventive activities such as: awareness on trafficking risks and damages, proactive engagement in drafting appropriate legislation and strategies, law enforcement monitoring and direct or indirect involvement in protective and supporting activities which benefit the victims of trafficking etc.Keywords: civil society, cooperation, police, human trafficking
Procedia PDF Downloads 3565661 Pavement Quality Evaluation Using Intelligent Compaction Technology: Overview of Some Case Studies in Oklahoma
Authors: Sagar Ghos, Andrew E. Elaryan, Syed Ashik Ali, Musharraf Zaman, Mohammed Ashiqur Rahman
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Achieving desired density during construction is an important indicator of pavement quality. Insufficient compaction often compromises pavement performance and service life. Intelligent compaction (IC) is an emerging technology for monitoring compaction quality during the construction of asphalt pavements. This paper aims to provide an overview of findings from four case studies in Oklahoma involving the compaction quality of asphalt pavements, namely SE 44th St project (Project 1) and EOC Turnpike project (Project 2), Highway 92 project (Project 3), and 108th Avenue project (Project 4). For this purpose, an IC technology, the intelligent compaction analyzer (ICA), developed at the University of Oklahoma, was used to evaluate compaction quality. Collected data include GPS locations, roller vibrations, roller speed, the direction of movement, and temperature of the asphalt mat. The collected data were analyzed using a widely used software, VETA. The average densities for Projects 1, 2, 3 and 4, were found as 89.8%, 91.50%, 90.7% and 87.5%, respectively. The maximum densities were found as 94.6%, 95.8%, 95.9%, and 89.7% for Projects 1, 2, 3, and 4, respectively. It was observed that the ICA estimated densities correlated well with the field core densities. The ICA results indicated that at least 90% of the asphalt mats were subjected to at least two roller passes. However, the number of passes required to achieve the desired density (94% to 97%) differed from project to project depending on the underlying layer. The results of these case studies show both opportunities and challenges in using IC for monitoring compaction quality during construction in real-time.Keywords: asphalt pavement construction, density, intelligent compaction, intelligent compaction analyzer, intelligent compaction measure value
Procedia PDF Downloads 1485660 Understanding Tourism Innovation through Fuzzy Measures
Authors: Marcella De Filippo, Delio Colangelo, Luca Farnia
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In recent decades, the hyper-competition of tourism scenario has implicated the maturity of many businesses, attributing a central role to innovative processes and their dissemination in the economy of company management. At the same time, it has defined the need for monitoring the application of innovations, in order to govern and improve the performance of companies and destinations. The study aims to analyze and define the innovation in the tourism sector. The research actions have concerned, on the one hand, some in-depth interviews with experts, identifying innovation in terms of process and product, digitalization, sustainability policies and, on the other hand, to evaluate the interaction between these factors, in terms of substitutability and complementarity in management scenarios, in order to identify which one is essential to be competitive in the global scenario. Fuzzy measures and Choquet integral were used to elicit Experts’ preferences. This method allows not only to evaluate the relative importance of each pillar, but also and more interestingly, the level of interaction, ranging from complementarity to substitutability, between pairs of factors. The results of the survey are the following: in terms of Shapley values, Experts assert that Innovation is the most important factor (32.32), followed by digitalization (31.86), Network (20.57) and Sustainability (15.25). In terms of Interaction indices, given the low degree of consensus among experts, the interaction between couples of criteria on average could be ignored; however, it is worth to note that the factors innovations and digitalization are those in which experts express the highest degree of interaction. However for some of them, these factors have a moderate level of complementarity (with a pick of 57.14), and others consider them moderately substitutes (with a pick of -39.58). Another example, although outlier is the interaction between network and digitalization, in which an expert consider them markedly substitutes (-77.08).Keywords: innovation, business model, tourism, fuzzy
Procedia PDF Downloads 2585659 The Influence of Imposter Phenomenon on the Experiences of Intimacy in Non-Binary Young Adults
Authors: Muskan Jain, Baiju Gopal
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Objectives: Intimacy in interpersonal relationships is integral to psychological health and everyday wellbeing; the focus is on intimacy, which can be described as feelings of closeness, connection, and belonging within relationships, which is influenced by an individual's gender identity as well as life experiences. The study aims to explore the experiences of intimacy of the non-binary gender; this marginalized community has increased risks of developing the imposter phenomenon. The study explores the influence of IP on the development and sustenance of intimacy in relationships. Methods: The present study accumulates detailed narratives from 10 non-binary young adults ages 18 to 25 in metropolitan cities of India. Thematic analysis was used for the data analysis. Results: Seven major themes have emerged revolving around internalized criticism and self-depreciating behavior, which causes distance between partners. The four themes that result in the internalization of criticism are lack of social stability, invalidation by social units, adverse life experiences, and estrangement due to gender identity. Three themes that encapsulate major difficulties in relationships are limited self-disclosure, inhibition of physical needs, and fear of taking space. The findings have been critically compared and contrasted with the existing body of literature in the domain, which sets the agenda for further inquiry. Conclusion: It is important for future studies to capture the experiences of non-binary genders in India to provide better therapeutic support in order to assist them in forming meaningful and authentic relationships, thus increasing overall wellbeing.Keywords: imposter phenomenon, intimacy, internalized criticism, marginalized community
Procedia PDF Downloads 515658 Non-Linear Assessment of Chromatographic Lipophilicity of Selected Steroid Derivatives
Authors: Milica Karadžić, Lidija Jevrić, Sanja Podunavac-Kuzmanović, Strahinja Kovačević, Anamarija Mandić, Aleksandar Oklješa, Andrea Nikolić, Marija Sakač, Katarina Penov Gaši
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Using chemometric approach, the relationships between the chromatographic lipophilicity and in silico molecular descriptors for twenty-nine selected steroid derivatives were studied. The chromatographic lipophilicity was predicted using artificial neural networks (ANNs) method. The most important in silico molecular descriptors were selected applying stepwise selection (SS) paired with partial least squares (PLS) method. Molecular descriptors with satisfactory variable importance in projection (VIP) values were selected for ANN modeling. The usefulness of generated models was confirmed by detailed statistical validation. High agreement between experimental and predicted values indicated that obtained models have good quality and high predictive ability. Global sensitivity analysis (GSA) confirmed the importance of each molecular descriptor used as an input variable. High-quality networks indicate a strong non-linear relationship between chromatographic lipophilicity and used in silico molecular descriptors. Applying selected molecular descriptors and generated ANNs the good prediction of chromatographic lipophilicity of the studied steroid derivatives can be obtained. This article is based upon work from COST Actions (CM1306 and CA15222), supported by COST (European Cooperation and Science and Technology).Keywords: artificial neural networks, chemometrics, global sensitivity analysis, liquid chromatography, steroids
Procedia PDF Downloads 3375657 Interaction Evaluation of Silver Ion and Silver Nanoparticles with Dithizone Complexes Using DFT Calculations and NMR Analysis
Authors: W. Nootcharin, S. Sujittra, K. Mayuso, K. Kornphimol, M. Rawiwan
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Silver has distinct antibacterial properties and has been used as a component of commercial products with many applications. An increasing number of commercial products cause risks of silver effects for human and environment such as the symptoms of Argyria and the release of silver to the environment. Therefore, the detection of silver in the aquatic environment is important. The colorimetric chemosensor is designed by the basic of ligand interactions with a metal ion, leading to the change of signals for the naked-eyes which are very useful method to this application. Dithizone ligand is considered as one of the effective chelating reagents for metal ions due to its high selectivity and sensitivity of a photochromic reaction for silver as well as the linear backbone of dithizone affords the rotation of various isomeric forms. The present study is focused on the conformation and interaction of silver ion and silver nanoparticles (AgNPs) with dithizone using density functional theory (DFT). The interaction parameters were determined in term of binding energy of complexes and the geometry optimization, frequency of the structures and calculation of binding energies using density functional approaches B3LYP and the 6-31G(d,p) basis set. Moreover, the interaction of silver–dithizone complexes was supported by UV–Vis spectroscopy, FT-IR spectrum that was simulated by using B3LYP/6-31G(d,p) and 1H NMR spectra calculation using B3LYP/6-311+G(2d,p) method compared with the experimental data. The results showed the ion exchange interaction between hydrogen of dithizone and silver atom, with minimized binding energies of silver–dithizone interaction. However, the result of AgNPs in the form of complexes with dithizone. Moreover, the AgNPs-dithizone complexes were confirmed by using transmission electron microscope (TEM). Therefore, the results can be the useful information for determination of complex interaction using the analysis of computer simulations.Keywords: silver nanoparticles, dithizone, DFT, NMR
Procedia PDF Downloads 2025656 Influence of Yield Stress and Compressive Strength on Direct Shear Behaviour of Steel Fibre-Reinforced Concrete
Authors: Bensaid Boulekbache, Mostefa Hamrat, Mohamed Chemrouk, Sofiane Amziane
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This study aims in examining the influence of the paste yield stress and compressive strength on the behaviour of fibre-reinforced concrete (FRC) versus direct shear. The parameters studied are the steel fibre contents, the aspect ratio of fibres and the concrete strength. Prismatic specimens of dimensions 10x10x35cm made of concrete of various yield stress reinforced with steel fibres hooked at the ends with three fibre volume fractions (i.e. 0, 0.5, and 1%) and two aspects ratio (65 and 80) were tested to direct shear. Three types of concretes with various compressive strength and yield stress were tested, an ordinary concrete (OC), a self-compacting concrete (SCC) and a high strength concrete (HSC). The concrete strengths investigated include 30 MPa for OC, 60 MPa for SCC and 80 MPa for HSC. The results show that the shear strength and ductility are affected and have been improved very significantly by the fibre contents, fibre aspect ratio and concrete strength. As the compressive strength and the volume fraction of fibres increase, the shear strength increases. However, yield stress of concrete has an important influence on the orientation and distribution of the fibres in the matrix. The ductility was much higher for ordinary and self-compacting concretes (concrete with good workability). The ductility in direct shear depends on the fibre orientation and is significantly improved when the fibres are perpendicular to the shear plane. On the contrary, for concrete with poor workability, an inadequate distribution and orientation of fibres occurred, leading to a weak contribution of the fibres to the direct shear behaviour.Keywords: concrete, fibre, direct shear, yield stress, orientation, strength
Procedia PDF Downloads 5355655 Aerobic Exercise Increases Circulating Hematopoietic Stem Cells and Endothelial Progenitor Cells
Authors: Khaled A. shady, Fagr B. Bazeed, Nashwa K. Abousamra, Ihab H. Elberawe, Ashraf E. shaalan, Mohamed A. Sobh
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Physical activity activates a variety of adult stem cells which might be released into the circulation or might be activated in their organ-resident state. A variety of stimuli such as metabolic, mechanical, and hormonal stimuli might by responsible for the mobilization. This study was done to know the changes in hematopoietic stem cells and endothelial progenitor in athletes in the 24 hours following 30 min of aerobic exercise. Methods: Ten healthy male's athlete's (age 20.7± 0.61 y) performed moderate running with 30 min at 80% of velocity of The IAT. Blood samples taken pre-, and immediately, 30 min, 2h, 6h and 24h post-exercise were analyzed for hematopoietic stem cells (HSCs ), endothelial progenitor cells (EPCs(, vascular endothelial growth factor (VEGF), nitric oxide (NO), lactic acid (LA), and white blood cells . HSCs and EPCs were quantified by flow cytometry. Results: After 30min of aerobic exercise significant increases in HSCs, EPC, VEGF, NO, LA and WBCs (p ˂ 0.05). This increase will be at different rates according to the timing of taking blood sample and was in the maximum rate of increase after 30 min of aerobic exercise. HSCs, EPC, NO and WBCs were in the maximum rate of increase 2h post exercise. In addition, VEGF was in the maximum rate of increase immediately post exercise and LA concentration not affected after exercise. Conclusion: These data suggest that HSCs and EPCs increased after aerobic exercise due to increase of VEGF which play an important role in mobilization of stem cells and promotes NO increase which contributes to increase EPCs.Keywords: physical activity, hematopoietic stem cells, mobilization, athletes
Procedia PDF Downloads 945654 Stress Analysis of Buried Pipes from Soil and Traffic Loads
Authors: A. Mohamed, A. El-Hamalawi, M. Frost, A. Connell
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Often design standards do not provide guidance or formulae for the calculation of stresses on buried pipelines caused by external loads. Frequently engineers rely on other methods and published sources of information to calculate such imposed stresses and a variety of methods can be used. This paper reviews three current approaches to soil pipeline interaction modelling to predict stresses on buried pipelines subjected to soil overburden and traffic loading. The traditional approach to use empirical stress formulas to calculate circumferential bending stresses on pipelines. The alternative approaches considered are the use of a finite element package to compute an estimate of circumferential bending stress and a proprietary stress analysis system (SURFLOAD) to estimate the circumferential bending stress. The results from analysis using the methods are presented and compared to experimental results in terms of predicted and measured circumferential stresses. This study shows that the approach used to assess externally generated stress is important and can lead to an over-conservative analysis. Using FE analysis either through SURFLOAD or a general FE package to predict circumferential stress is the most accurate way to undertake stress analysis due to traffic and soil loads. Although conservative, classical empirical methods will continue to be applied to the analysis of buried pipelines, an opportunity exists, therefore, in many circumstances, to use applied numerical techniques, made possible by advances in finite element analysis.Keywords: buried pipelines, circumferential bending stress, finite element analysis, soil overburden, soil pipeline interaction analysis (SPIA), traffic loadings
Procedia PDF Downloads 4335653 Generation of Renewable Energy Through Photovoltaic Panels, Albania Photovoltaic Capacity
Authors: Dylber Qema
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Driven by recent developments in technology and the growing concern about the sustainability and environmental impact of conventional fuel use, the possibility of producing clean and sustainable energy in significant quantities from renewable energy sources has sparked interest all over the world. Solar energy is one of the sources for the generation of electricity, with no emissions or environmental pollution. The electricity produced by photovoltaics can supply a home or business and can even be sold or exchanged with the grid operator. A very positive effect of using photovoltaic modules is that they do not produce greenhouse gases and do not produce chemical waste, unlike all other forms of energy production. Photovoltaics are becoming one of the largest investments in the field of renewable generating units. Improving the reliability of the electric power system is one of the most important impacts of the installation of photovoltaics (PV). Renewable energy sources are so large that they can meet the energy demands of the whole world, thus enabling sustainable supply as well as reducing local and global atmospheric emissions. Albania is rated by experts as one of the most favorable countries in Europe for the production of electricity from solar panels. But the country currently produces about 1% of its energy from the sun, while the rest of the needs are met by hydropower plants and imports. Albania has very good characteristics in terms of solar radiation (about 1300–1400 kW/m2). Solar energy has great potential and is a permanent source of energy with greater economic efficiency. Photovoltaic energy is also seen as an alternative, as long periods of drought in Albania have produced crises and high costs for securing energy in the foreign market.Keywords: capacity, ministry of tourism and environment, obstacles, photovoltaic energy, sustainable
Procedia PDF Downloads 485652 Community’s Role in Slum Development: A Case Study of the Kabul Old City
Authors: Habibi Said Mustafa, Hiroko Ono
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Kabul, the capital of Afghanistan, has witnessed a major population growth in the last decades which caused a significant increase in the number of informal settlements. The residents are suffering from many problems such as poor infrastructure, shortage of public facilities, depriving of the sense of ownership and facing much environmental degradation. Even though majority of the residents are living in such condition, the government response has been quite weak. The government’s main planning strategy has been upgrading in the form of provision of facilities and improving elements of physical infrastructure, unfortunately most of the projects which had not community’s support, faced with lots of challenges such as people’s resistance or even in some cases the project rather than solving the problem, compounded them to a worse condition. A major reason as to why many projects have not been effective in achieving certain objectives in the past is the results of local people were not being involved. Community participation plays an important role in slum development projects. The development of an integrated urban development concept these days without the mobilization of participants and community seems difficult and impossible. Therefore this paper looks into factors and methods which can help in creating a participatory approach for developing the slums in Kabul city. Furthermore, it describes the result of a questionnaire which was conducted on a part of the Kabul Old City due to hear resident’s problem related to the slum upgrading and collect their opinions on this regard. The research also points out some factors which can severely hamper the successful implementation of a slum upgrading project if not adequately addressed.Keywords: Community empowerment, Informal settlements, Job opportunities, People participation
Procedia PDF Downloads 1655651 Geochemical Study of Natural Bitumen, Condensate and Gas Seeps from Sousse Area, Central Tunisia
Authors: Belhaj Mohamed, M. Saidi, N. Boucherab, N. Ouertani, I. Bouazizi, M. Ben Jrad
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Natural hydrocarbon seepage has helped petroleum exploration as a direct indicator of gas and/or oil subsurface accumulations. Surface macro-seeps are generally an indication of a fault in an active Petroleum Seepage System belonging to a Total Petroleum System. This paper describes a case study in which multiple analytical techniques were used to identify and characterize trace petroleum-related hydrocarbons and other volatile organic compounds in groundwater samples collected from Sousse aquifer (Central Tunisia). The analytical techniques used for analyses of water samples included gas chromatography-mass spectrometry (GC-MS), capillary GC with flame-ionization detection, Compund Specific Isotope Analysis, Rock Eval Pyrolysis. The objective of the study was to confirm the presence of gasoline and other petroleum products or other volatile organic pollutants in those samples in order to assess the respective implication of each of the potentially responsible parties to the contamination of the aquifer. In addition, the degree of contamination at different depths in the aquifer was also of interest. The oil and gas seeps have been investigated using biomarker and stable carbon isotope analyses to perform oil-oil and oil-source rock correlations. The seepage gases are characterized by high CH4 content, very low δ13CCH4 values (-71,9 ‰) and high C1/C1–5 ratios (0.95–1.0), light deuterium–hydrogen isotope ratios (-198 ‰) and light δ13CC2 and δ13CCO2 values (-23,8‰ and-23,8‰ respectively) indicating a thermogenic origin with the contribution of the biogenic gas. An organic geochemistry study was carried out on the more ten oil seep samples. This study includes light hydrocarbon and biomarkers analyses (hopanes, steranes, n-alkanes, acyclic isoprenoids, and aromatic steroids) using GC and GC-MS. The studied samples show at least two distinct families, suggesting two different types of crude oil origins: the first oil seeps appears to be highly mature, showing evidence of chemical and/or biological degradation and was derived from a clay-rich source rock deposited in suboxic conditions. It has been sourced mainly by the lower Fahdene (Albian) source rocks. The second oil seeps was derived from a carbonate-rich source rock deposited in anoxic conditions, well correlated with the Bahloul (Cenomanian-Turonian) source rock.Keywords: biomarkers, oil and gas seeps, organic geochemistry, source rock
Procedia PDF Downloads 4375650 Simscape Library for Large-Signal Physical Network Modeling of Inertial Microelectromechanical Devices
Authors: S. Srinivasan, E. Cretu
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The information flow (e.g. block-diagram or signal flow graph) paradigm for the design and simulation of Microelectromechanical (MEMS)-based systems allows to model MEMS devices using causal transfer functions easily, and interface them with electronic subsystems for fast system-level explorations of design alternatives and optimization. Nevertheless, the physical bi-directional coupling between different energy domains is not easily captured in causal signal flow modeling. Moreover, models of fundamental components acting as building blocks (e.g. gap-varying MEMS capacitor structures) depend not only on the component, but also on the specific excitation mode (e.g. voltage or charge-actuation). In contrast, the energy flow modeling paradigm in terms of generalized across-through variables offers an acausal perspective, separating clearly the physical model from the boundary conditions. This promotes reusability and the use of primitive physical models for assembling MEMS devices from primitive structures, based on the interconnection topology in generalized circuits. The physical modeling capabilities of Simscape have been used in the present work in order to develop a MEMS library containing parameterized fundamental building blocks (area and gap-varying MEMS capacitors, nonlinear springs, displacement stoppers, etc.) for the design, simulation and optimization of MEMS inertial sensors. The models capture both the nonlinear electromechanical interactions and geometrical nonlinearities and can be used for both small and large signal analyses, including the numerical computation of pull-in voltages (stability loss). Simscape behavioral modeling language was used for the implementation of reduced-order macro models, that present the advantage of a seamless interface with Simulink blocks, for creating hybrid information/energy flow system models. Test bench simulations of the library models compare favorably with both analytical results and with more in-depth finite element simulations performed in ANSYS. Separate MEMS-electronic integration tests were done on closed-loop MEMS accelerometers, where Simscape was used for modeling the MEMS device and Simulink for the electronic subsystem.Keywords: across-through variables, electromechanical coupling, energy flow, information flow, Matlab/Simulink, MEMS, nonlinear, pull-in instability, reduced order macro models, Simscape
Procedia PDF Downloads 1265649 Analysis of Determinants of Growth of Small and Medium Enterprises in Kwara State, Nigeria
Authors: Hussaini Tunde Subairu
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Small and Medium Enterprises (SMEs) sectors serve as catalyst for employment generation, national growth, poverty reduction and economic development in developing and developed countries. However, in Nigeria despite copious and plethora of government policies and stimulus schemes directed at SMEs, the sector is still characterized by high rate of failure and discontinuities. This study therefore investigated owners/managers profile, firms characteristics and external factors as possible determinants of SMEs growth from selected SMEs in Kwara State. Primary data were sourced from 200 SMEs respondents registered with the National Association of Small and Medium Enterprises (NASMES) in Kwara State Central Senatorial District. Multiple Regressions Analysis (MRA) was used to analyze the relationship between dependent and independent variables, and pair wise correlation was employed to examine the relationship among independent variables. The Analysis of Variable (ANOVA) was employed to indicate the overall significant of the model The findings revealed that Analysis of variance (ANOVA) put the value of F-statistics at 420.45 and p-value at 0.000 was significant. The values of R2 and Adjusted R2 of 0.9643 and 0.9620 respectively suggested that 96 percent of variations in employment growth were explained by the explanatory variables. The level of technical and managerial education has t- value of 24.14 and p-value of 0.001, length of managers/owners experience in similar trade with t- value of 21.37 and p-value of 0.001, age of managers/owners with t- value of 42.98 and p-value of 0.001, firm age with t- value of 25.91 and p-value of 0.001, numbers of firms in a cluster with t- value of 7.20 and p-value of 0.001, access to formal finance with t-value of 5.56 and p-value of 0.001, firm technology innovation with t- value of 25.32 and p-value of 0.01, institutional support with t- value of 18.89 and p-value of 0.01, globalization with t- value of 9.78 and p-value of 0.01, and infrastructure with t-value of 10.75 and p-value of 0.01. The result also indicated that initial size has t-value of -1.71 and p-value of 0.090 which is consistent with Gibrat’s Law. The study concluded that owners/managers profile, firm specific characteristics and external factors substantially influenced employment growths of SMEs in the study area. Therefore, policy implication should enhance human capital development of SMEs owners/managers, and strengthen fiscal policy thrust through imposition on tariff regime to minimize effect of globalization. Governments at all level must support SMEs growth radically and enhance institutional support for SMEs growth and radically and significantly upgrading key infrastructure as rail/roads, rail, telecommunications, water and power.Keywords: external factors, firm specific characteristics, owners / manager profile, small and medium enterprises
Procedia PDF Downloads 2375648 Investigation of the Low-Level Jet Role in Transportation of Shamal Dust Storms in Southwest Iran
Authors: Nasim Hossein Hamzeh, Abbas Ranjbar Saadat Abadi, Maggie Chel Gee Ooi, Steven Soon-Kai Kong, Christian Opp
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Dust storm is one of the most important natural disasters in the world, where the Middle East suffers frequently due to the existence of the dust belt region. As a country in the Middle East, Iran mostly is affected by the dust storms from some internal and also external dust sources, mostly originating from deserts in Iraq, Syria, and Saudi Arabia. In this study, some severe Shamal dust storms were investigated in Southwest Iran. The measured 〖PM〗_10 reached up to 834 μg m-3 in some stations in west Iran and Iran-Iraq borders, while the measured 〖PM〗_10 reached up to 4947 μg m-3 SW stations in northern shores of the Persian Gulf. During these severe dust storms, a low-level jet was observed at 930hPa atmospheric level in north Iraq and south Iraq. the jet core and its width were about 16 ms-1 and 100 km, respectively, in the cases where it is located in the NW regions of Iraq and northeastern Syria (at 35°N and 40-41°E), So the jet was stronger at higher latitudes (34°N - 35°N) than at lower latitudes (32°N). Therefore, suitable conditions have been created for lifting of dust sources located in northwestern Iraq and northeastern Syria. The topography surrounding the Mesopotamia and north of the Persian Gulf play a major role in the development of the Low-Level Jet through the interaction of meteorological conditions and mountain forcing. Also, the output of CALIPSO satellite images show dust rising to higher than 5 km in these dust cases, that confirming the influence of Shamal wind on the dust storm occurrence.Keywords: dust storm, shamal wind, the persian gulf, southwest Iran
Procedia PDF Downloads 865647 Acid Attack on Cement Mortars Modified with Rubber Aggregates and EVA Polymer Binder
Authors: Konstantinos Sotiriadis, Michael Tupý, Nikol Žižková, Vít Petránek
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The acid attack on cement mortars modified with rubber aggregates and EVA polymer binder was studied. Mortar specimens were prepared using a type CEM I 42.5 Portland cement and siliceous sand, as well as by substituting 25% of sand with shredded used automobile tires, and by adding EVA polymer in two percentages (5% and 10% of cement mass). Some specimens were only air cured, at laboratory conditions, and their compressive strength and water absorption were determined. The rest specimens were stored in acid solutions (HCl, H2SO4, HNO3) after 28 days of initial curing, and stored at laboratory temperature. Compressive strength tests, mass measurements and visual inspection took place for 28 days. Compressive strength and water absorption of the air-cured specimens were significantly decreased when rubber aggregates are used. The addition of EVA polymer further reduced water absorption, while had no important impact on strength. Compressive strength values were affected in a greater extent by hydrochloric acid solution, followed by sulfate and nitric acid solutions. The addition of EVA polymer decreased compressive strength loss for the specimens with rubber aggregates stored in hydrochloric and nitric acid solutions. The specimens without polymer binder showed similar mass loss, which was higher in sulfate acid solution followed by hydrochloric and nitric acid solutions. The use of EVA polymer delayed mass loss, while its content did not affect it significantly.Keywords: acid attack, mortar, EVA polymer, rubber aggregates
Procedia PDF Downloads 281