Search results for: bridging theory and applications
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10647

Search results for: bridging theory and applications

567 Implementation of Real-World Learning Experiences in Teaching Courses of Medical Microbiology and Dietetics for Health Science Students

Authors: Miriam I. Jimenez-Perez, Mariana C. Orellana-Haro, Carolina Guzman-Brambila

Abstract:

As part of microbiology and dietetics courses, students of medicine and nutrition analyze the main pathogenic microorganisms and perform dietary analyzes. The course of microbiology describes in a general way the main pathogens including bacteria, viruses, fungi, and parasites, as well as their interaction with the human species. We hypothesize that lack of practical application of the course causes the students not to find the value and the clinical application of it when in reality it is a matter of great importance for healthcare in our country. The courses of the medical microbiology and dietetics are mostly theoretical and only a few hours of laboratory practices. Therefore, it is necessary the incorporation of new innovative techniques that involve more practices and community fieldwork, real cases analysis and real-life situations. The purpose of this intervention was to incorporate real-world learning experiences in the instruction of medical microbiology and dietetics courses, in order to improve the learning process, understanding and the application in the field. During a period of 6 months, medicine and nutrition students worked in a community of urban poverty. We worked with 90 children between 4 and 6 years of age from low-income families with no access to medical services, to give an infectious diagnosis related to nutritional status in these children. We expect that this intervention would give a different kind of context to medical microbiology and dietetics students improving their learning process, applying their knowledge and laboratory practices to help a needed community. First, students learned basic skills in microbiology diagnosis test during laboratory sessions. Once, students acquired abilities to make biochemical probes and handle biological samples, they went to the community and took stool samples from children (with the corresponding informed consent). Students processed the samples in the laboratory, searching for enteropathogenic microorganism with RapID™ ONE system (Thermo Scientific™) and parasites using Willis and Malloy modified technique. Finally, they compared the results with the nutritional status of the children, previously measured by anthropometric indicators. The anthropometric results were interpreted by the OMS Anthro software (WHO, 2011). The microbiological result was interpreted by ERIC® Electronic RapID™ Code Compendium software and validated by a physician. The results were analyses of infectious outcomes and nutritional status. Related to fieldwork community learning experiences, our students improved their knowledge in microbiology and were capable of applying this knowledge in a real-life situation. They found this kind of learning useful when they translate theory to a real-life situation. For most of our students, this is their first contact as health caregivers with real population, and this contact is very important to help them understand the reality of many people in Mexico. In conclusion, real-world or fieldwork learning experiences empower our students to have a real and better understanding of how they can apply their knowledge in microbiology and dietetics and help a much- needed population, this is the kind of reality that many people live in our country.

Keywords: real-world learning experiences, medical microbiology, dietetics, nutritional status, infectious status.

Procedia PDF Downloads 111
566 The U.S. Missile Defense Shield and Global Security Destabilization: An Inconclusive Link

Authors: Michael A. Unbehauen, Gregory D. Sloan, Alberto J. Squatrito

Abstract:

Missile proliferation and global stability are intrinsically linked. Missile threats continually appear at the forefront of global security issues. North Korea’s recently demonstrated nuclear and intercontinental ballistic missile (ICBM) capabilities, for the first time since the Cold War, renewed public interest in strategic missile defense capabilities. To protect from limited ICBM attacks from so-called rogue actors, the United States developed the Ground-based Midcourse Defense (GMD) system. This study examines if the GMD missile defense shield has contributed to a safer world or triggered a new arms race. Based upon increased missile-related developments and the lack of adherence to international missile treaties, it is generally perceived that the GMD system is a destabilizing factor for global security. By examining the current state of arms control treaties as well as existing missile arsenals and ongoing efforts in technologies to overcome U.S. missile defenses, this study seeks to analyze the contribution of GMD to global stability. A thorough investigation cannot ignore that, through the establishment of this limited capability, the U.S. violated longstanding, successful weapons treaties and caused concern among states that possess ICBMs. GMD capability contributes to the perception that ICBM arsenals could become ineffective, creating an imbalance in favor of the United States, leading to increased global instability and tension. While blame for the deterioration of global stability and non-adherence to arms control treaties is often placed on U.S. missile defense, the facts do not necessarily support this view. The notion of a renewed arms race due to GMD is supported neither by current missile arsenals nor by the inevitable development of new and enhanced missile technology, to include multiple independently targeted reentry vehicles (MIRVs), maneuverable reentry vehicles (MaRVs), and hypersonic glide vehicles (HGVs). The methodology in this study encapsulates a period of time, pre- and post-GMD introduction, while analyzing international treaty adherence, missile counts and types, and research in new missile technologies. The decline in international treaty adherence, coupled with a measurable increase in the number and types of missiles or research in new missile technologies during the period after the introduction of GMD, could be perceived as a clear indicator of GMD contributing to global instability. However, research into improved technology (MIRV, MaRV and HGV) prior to GMD, as well as a decline of various global missile inventories and testing of systems during this same period, would seem to invalidate this theory. U.S. adversaries have exploited the perception of the U.S. missile defense shield as a destabilizing factor as a pretext to strengthen and modernize their militaries and justify their policies. As a result, it can be concluded that global stability has not significantly decreased due to GMD; but rather, the natural progression of technological and missile development would inherently include innovative and dynamic approaches to target engagement, deterrence, and national defense.

Keywords: arms control, arms race, global security, GMD, ICBM, missile defense, proliferation

Procedia PDF Downloads 127
565 Rendering Religious References in English: Naguib Mahfouz in the Arabic as a Foreign Language Classroom

Authors: Shereen Yehia El Ezabi

Abstract:

The transition from the advanced to the superior level of Arabic proficiency is widely known to pose considerable challenges for English speaking students of Arabic as a Foreign Language (AFL). Apart from the increasing complexity of the grammar at this juncture, together with the sprawling vocabulary, to name but two of those challenges, there is also the somewhat less studied hurdle along the way to superior level proficiency, namely, the seeming opacity of many aspects of Arab/ic culture to such learners. This presentation tackles one specific dimension of such issues: religious references in literary texts. It illustrates how carefully constructed translation activities may be used to expand and deepen students’ understanding and use of them. This is shown to be vital for making the leap to the desired competency, given that such elements, as reflected in customs, traditions, institutions, worldviews, and formulaic expressions lie at the very core of Arabic culture and, as such, pervade all modes and levels of Arabic discourse. A short story from the collection “Stories from Our Alley”, by preeminent novelist Naguib Mahfouz is selected for use in this context, being particularly replete with such religious references, of which religious expressions will form the focus of the presentation. As a miniature literary work, it provides an organic whole, so to speak, within which to explore with the class the most precise denotation, as well as the subtlest connotation of each expression in an effort to reach the ‘best’ English rendering. The term ‘best’ refers to approximating the meaning in its full complexity from the source text, in this case Arabic, to the target text, English, according to the concept of equivalence in translation theory. The presentation will show how such a process generates the sort of thorough discussion and close text analysis which allows students to gain valuable insight into this central idiom of Arabic. A variety of translation methods will be highlighted, gleaned from the presenter’s extensive work with advanced/superior students in the Center for Arabic Study Abroad (CASA) program at the American University in Cairo. These begin with the literal rendering of expressions, with the purpose of reinforcing vocabulary learning and practicing the rules of derivational morphology as they form each word, since the larger context remains that of an AFL class, as opposed to a translation skills program. However, departures from the literal approach are subsequently explored by degrees, moving along the spectrum of functional and pragmatic freer translations in order to transmit the ‘real’ meaning in readable English to the target audience- no matter how culture/religion specific the expression- while remaining faithful to the original. Samples from students’ work pre and post discussion will be shared, demonstrating how class consensus is formed as to the final English rendering, proposed as the closest match to the Arabic, and shown to be the result of the above activities. Finally, a few examples of translation work which students have gone on to publish will be shared to corroborate the effectiveness of this teaching practice.

Keywords: superior level proficiency in Arabic as a foreign language, teaching Arabic as a foreign language, teaching idiomatic expressions, translation in foreign language teaching

Procedia PDF Downloads 181
564 Fly ash Contamination in Groundwater and its Implications on Local Climate Change

Authors: Rajkumar Ghosh

Abstract:

Fly ash, a byproduct of coal combustion, has become a prevalent environmental concern due to its potential impact on both groundwater quality and local climate change. This study aims to provide an in-depth analysis of the various mechanisms through which fly ash contaminates groundwater, as well as the possible consequences of this contamination on local climate change. The presence of fly ash in groundwater not only poses a risk to human health but also has the potential to influence local climate change through complex interactions. Although fly ash has various applications in construction and other industries, improper disposal and lack of containment measures have led to its infiltration into groundwater systems. Through a comprehensive review of existing literature and case studies, the interactions between fly ash and groundwater systems, assess the effects on hydrology, and discuss the implications for the broader climate. This section reviews the pathways through which fly ash enters groundwater, including leaching from disposal sites, infiltration through soil, and migration from surface water bodies. The physical and chemical characteristics of fly ash that contribute to its mobility and persistence in groundwater. The introduction of fly ash into groundwater can alter its chemical composition, leading to an increase in the concentration of heavy metals, metalloids, and other potentially toxic elements. The mechanisms of contaminant transport and highlight the potential risks to human health and ecosystems. Fly ash contamination in groundwater may influence the hydrological cycle through changes in groundwater recharge, discharge, and flow dynamics. This section examines the implications of altered hydrology on local water availability, aquatic habitats, and overall ecosystem health. The presence of fly ash in groundwater may have direct and indirect effects on local climate change. The role of fly ash as a potent greenhouse gas absorber and its contribution to radiative forcing. Additionally, investigation of the possible feedback mechanisms between groundwater contamination and climate change, such as altered vegetation patterns and changes in local temperature and precipitation patterns. In this section, potential mitigation and remediation techniques to minimize fly ash contamination in groundwater are analyzed. These may include improved waste management practices, engineered barriers, groundwater remediation technologies, and sustainable fly ash utilization. This paper highlights the critical link between fly ash contamination in groundwater and its potential contribution to local climate change. It emphasizes the importance of addressing this issue promptly through a combination of preventive measures, effective management strategies, and continuous monitoring. By understanding the interconnections between fly ash contamination, groundwater quality, and local climate, towards creating a more resilient and sustainable environment for future generations. The findings of this research can assist policymakers and environmental managers in formulating sustainable strategies to mitigate fly ash contamination and minimize its contribution to climate change.

Keywords: groundwater, climate, sustainable environment, fly ash contamination

Procedia PDF Downloads 62
563 Towards a Measuring Tool to Encourage Knowledge Sharing in Emerging Knowledge Organizations: The Who, the What and the How

Authors: Rachel Barker

Abstract:

The exponential velocity in the truly knowledge-intensive world today has increasingly bombarded organizations with unfathomable challenges. Hence organizations are introduced to strange lexicons of descriptors belonging to a new paradigm of who, what and how knowledge at individual and organizational levels should be managed. Although organizational knowledge has been recognized as a valuable intangible resource that holds the key to competitive advantage, little progress has been made in understanding how knowledge sharing at individual level could benefit knowledge use at collective level to ensure added value. The research problem is that a lack of research exists to measure knowledge sharing through a multi-layered structure of ideas with at its foundation, philosophical assumptions to support presuppositions and commitment which requires actual findings from measured variables to confirm observed and expected events. The purpose of this paper is to address this problem by presenting a theoretical approach to measure knowledge sharing in emerging knowledge organizations. The research question is that despite the competitive necessity of becoming a knowledge-based organization, leaders have found it difficult to transform their organizations due to a lack of knowledge on who, what and how it should be done. The main premise of this research is based on the challenge for knowledge leaders to develop an organizational culture conducive to the sharing of knowledge and where learning becomes the norm. The theoretical constructs were derived and based on the three components of the knowledge management theory, namely technical, communication and human components where it is suggested that this knowledge infrastructure could ensure effective management. While it is realised that it might be a little problematic to implement and measure all relevant concepts, this paper presents effect of eight critical success factors (CSFs) namely: organizational strategy, organizational culture, systems and infrastructure, intellectual capital, knowledge integration, organizational learning, motivation/performance measures and innovation. These CSFs have been identified based on a comprehensive literature review of existing research and tested in a new framework adapted from four perspectives of the balanced score card (BSC). Based on these CSFs and their items, an instrument was designed and tested among managers and employees of a purposefully selected engineering company in South Africa who relies on knowledge sharing to ensure their competitive advantage. Rigorous pretesting through personal interviews with executives and a number of academics took place to validate the instrument and to improve the quality of items and correct wording of issues. Through analysis of surveys collected, this research empirically models and uncovers key aspects of these dimensions based on the CSFs. Reliability of the instrument was calculated by Cronbach’s a for the two sections of the instrument on organizational and individual levels.The construct validity was confirmed by using factor analysis. The impact of the results was tested using structural equation modelling and proved to be a basis for implementing and understanding the competitive predisposition of the organization as it enters the process of knowledge management. In addition, they realised the importance to consolidate their knowledge assets to create value that is sustainable over time.

Keywords: innovation, intellectual capital, knowledge sharing, performance measures

Procedia PDF Downloads 179
562 Facial Recognition of University Entrance Exam Candidates using FaceMatch Software in Iran

Authors: Mahshid Arabi

Abstract:

In recent years, remarkable advancements in the fields of artificial intelligence and machine learning have led to the development of facial recognition technologies. These technologies are now employed in a wide range of applications, including security, surveillance, healthcare, and education. In the field of education, the identification of university entrance exam candidates has been one of the fundamental challenges. Traditional methods such as using ID cards and handwritten signatures are not only inefficient and prone to fraud but also susceptible to errors. In this context, utilizing advanced technologies like facial recognition can be an effective and efficient solution to increase the accuracy and reliability of identity verification in entrance exams. This article examines the use of FaceMatch software for recognizing the faces of university entrance exam candidates in Iran. The main objective of this research is to evaluate the efficiency and accuracy of FaceMatch software in identifying university entrance exam candidates to prevent fraud and ensure the authenticity of individuals' identities. Additionally, this research investigates the advantages and challenges of using this technology in Iran's educational systems. This research was conducted using an experimental method and random sampling. In this study, 1000 university entrance exam candidates in Iran were selected as samples. The facial images of these candidates were processed and analyzed using FaceMatch software. The software's accuracy and efficiency were evaluated using various metrics, including accuracy rate, error rate, and processing time. The research results indicated that FaceMatch software could accurately identify candidates with a precision of 98.5%. The software's error rate was less than 1.5%, demonstrating its high efficiency in facial recognition. Additionally, the average processing time for each candidate's image was less than 2 seconds, indicating the software's high efficiency. Statistical evaluation of the results using precise statistical tests, including analysis of variance (ANOVA) and t-test, showed that the observed differences were significant, and the software's accuracy in identity verification is high. The findings of this research suggest that FaceMatch software can be effectively used as a tool for identifying university entrance exam candidates in Iran. This technology not only enhances security and prevents fraud but also simplifies and streamlines the exam administration process. However, challenges such as preserving candidates' privacy and the costs of implementation must also be considered. The use of facial recognition technology with FaceMatch software in Iran's educational systems can be an effective solution for preventing fraud and ensuring the authenticity of university entrance exam candidates' identities. Given the promising results of this research, it is recommended that this technology be more widely implemented and utilized in the country's educational systems.

Keywords: facial recognition, FaceMatch software, Iran, university entrance exam

Procedia PDF Downloads 23
561 Ultrasound Assisted Alkaline Potassium Permanganate Pre-Treatment of Spent Coffee Waste

Authors: Rajeev Ravindran, Amit K. Jaiswal

Abstract:

Lignocellulose is the largest reservoir of inexpensive, renewable source of carbon. It is composed of lignin, cellulose and hemicellulose. Cellulose and hemicellulose is composed of reducing sugars glucose, xylose and several other monosaccharides which can be metabolised by microorganisms to produce several value added products such as biofuels, enzymes, aminoacids etc. Enzymatic treatment of lignocellulose leads to the release of monosaccharides such as glucose and xylose. However, factors such as the presence of lignin, crystalline cellulose, acetyl groups, pectin etc. contributes to recalcitrance restricting the effective enzymatic hydrolysis of cellulose and hemicellulose. In order to overcome these problems, pre-treatment of lignocellulose is generally carried out which essentially facilitate better degradation of lignocellulose. A range of pre-treatment strategy is commonly employed based on its mode of action viz. physical, chemical, biological and physico-chemical. However, existing pretreatment strategies result in lower sugar yield and formation of inhibitory compounds. In order to overcome these problems, we proposes a novel pre-treatment, which utilises the superior oxidising capacity of alkaline potassium permanganate assisted by ultra-sonication to break the covalent bonds in spent coffee waste to remove recalcitrant compounds such as lignin. The pre-treatment was conducted for 30 minutes using 2% (w/v) potassium permanganate at room temperature with solid to liquid ratio of 1:10. The pre-treated spent coffee waste (SCW) was subjected to enzymatic hydrolysis using enzymes cellulase and hemicellulase. Shake flask experiments were conducted with a working volume of 50mL buffer containing 1% substrate. The results showed that the novel pre-treatment strategy yielded 7 g/L of reducing sugar as compared to 3.71 g/L obtained from biomass that had undergone dilute acid hydrolysis after 24 hours. From the results obtained it is fairly certain that ultrasonication assists the oxidation of recalcitrant components in lignocellulose by potassium permanganate. Enzyme hydrolysis studies suggest that ultrasound assisted alkaline potassium permanganate pre-treatment is far superior over treatment by dilute acid. Furthermore, SEM, XRD and FTIR were carried out to analyse the effect of the new pre-treatment strategy on structure and crystallinity of pre-treated spent coffee wastes. This novel one-step pre-treatment strategy was implemented under mild conditions and exhibited high efficiency in the enzymatic hydrolysis of spent coffee waste. Further study and scale up is in progress in order to realise future industrial applications.

Keywords: spent coffee waste, alkaline potassium permanganate, ultra-sonication, physical characterisation

Procedia PDF Downloads 329
560 The Effectiveness of Multiphase Flow in Well- Control Operations

Authors: Ahmed Borg, Elsa Aristodemou, Attia Attia

Abstract:

Well control involves managing the circulating drilling fluid within the wells and avoiding kicks and blowouts as these can lead to losses in human life and drilling facilities. Current practices for good control incorporate predictions of pressure losses through computational models. Developing a realistic hydraulic model for a good control problem is a very complicated process due to the existence of a complex multiphase region, which usually contains a non-Newtonian drilling fluid and the miscibility of formation gas in drilling fluid. The current approaches assume an inaccurate flow fluid model within the well, which leads to incorrect pressure loss calculations. To overcome this problem, researchers have been considering the more complex two-phase fluid flow models. However, even these more sophisticated two-phase models are unsuitable for applications where pressure dynamics are important, such as in managed pressure drilling. This study aims to develop and implement new fluid flow models that take into consideration the miscibility of fluids as well as their non-Newtonian properties for enabling realistic kick treatment. furthermore, a corresponding numerical solution method is built with an enriched data bank. The research work considers and implements models that take into consideration the effect of two phases in kick treatment for well control in conventional drilling. In this work, a corresponding numerical solution method is built with an enriched data bank. Software STARCCM+ for the computational studies to study the important parameters to describe wellbore multiphase flow, the mass flow rate, volumetric fraction, and velocity of each phase. Results showed that based on the analysis of these simulation studies, a coarser full-scale model of the wellbore, including chemical modeling established. The focus of the investigations was put on the near drill bit section. This inflow area shows certain characteristics that are dominated by the inflow conditions of the gas as well as by the configuration of the mud stream entering the annulus. Without considering the gas solubility effect, the bottom hole pressure could be underestimated by 4.2%, while the bottom hole temperature is overestimated by 3.2%. and without considering the heat transfer effect, the bottom hole pressure could be overestimated by 11.4% under steady flow conditions. Besides, larger reservoir pressure leads to a larger gas fraction in the wellbore. However, reservoir pressure has a minor effect on the steady wellbore temperature. Also as choke pressure increases, less gas will exist in the annulus in the form of free gas.

Keywords: multiphase flow, well- control, STARCCM+, petroleum engineering and gas technology, computational fluid dynamic

Procedia PDF Downloads 100
559 Personality, Coping, Quality of Life, and Distress in Persons with Hearing Loss: A Cross-Sectional Study of Patients Referred to an Audiological Service

Authors: Oyvind Nordvik, Peder O. L. Heggdal, Jonas Brannstrom, Flemming Vassbotn, Anne Kari Aarstad, Hans Jorgen Aarstad

Abstract:

Background: Hearing Loss (HL) is a condition that may affect people in all stages of life, but the prevalence increases with age, mostly because of age-related HL, generally referred to as presbyacusis. As human speech is related to relatively high frequencies, even a limited hearing loss at high frequencies may cause impaired speech intelligibility. Being diagnosed with, treated for and living with a chronic condition such as HL, must for many be a disabling and stressful condition that put ones coping resources to test. Stress is a natural part of life and most people will experience stressful events or periods. Chronic diseases, such as HL, are risk factor for distress in individuals, causing anxiety and lowered mood. How an individual cope with HL may be closely connected to the level of distress he or she is experiencing and to personality, which can be defined as those characteristics of a person that account for consistent patterns of feelings, thinking, and behavior. Thus, as to distress in life, such as illness or disease, available coping strategies may be more important than the challenge itself. The same line of arguments applies to level of experienced health-related quality of life (HRQoL). Aim: The aim of this study was to investigate the relationship between distress, HRQoL, reported hearing loss, personality and coping in patients with HL. Method: 158 adult (aged 18-78 years) patients with HL, referred for hearing aid (HA) fitting at Haukeland University Hospital in western Norway, participated in the study. Both first-time users, as well as patients referred for HA renewals were included. First-time users had been pre-examined by an ENT-specialist. The questionnaires were answered before the actual HA fitting procedure. The pure-tone average (PTA; frequencies 0.5, 1, 2, and 4 kHz) was determined for each ear. The Eysenck personality inventory, neuroticism and lie scales, the Theoretically Originated Measure of the Cognitive Activation Theory of Stress (TOMCATS) measuring active coping, hopelessness and helplessness, as well as distress (General Health Questionnaire (GHQ) - 12 items) and the EORTC Quality of Life Questionnaire general part were answered. In addition, we used a revised and shortened version of the Abbreviated Profile of Hearing Aid Benefit (APHAB) as a measure of patient-reported hearing loss. Results: Significant correlations were determined between APHAB (weak), HRQoL scores (strong), distress scores (strong) on the one side and personality and choice of coping scores on the other side. As measured by stepwise regression analyses, the distress and HRQoL scores were scored secondary to the obtained personality and coping scores. The APHAB scores were as determined by regression analyses scored secondary to PTA (best ear), level of neuroticism and lie score. Conclusion: We found that reported employed coping style, distress/HRQoL and personality are closely connected to each other in this patient group. Patient-reported HL was associated to hearing level and personality. There is need for further investigations on these questions, and how these associations may influence the clinical context.

Keywords: coping, distress, hearing loss, personality

Procedia PDF Downloads 127
558 Effects of the Exit from Budget Support on Good Governance: Findings from Four Sub-Saharan Countries

Authors: Magdalena Orth, Gunnar Gotz

Abstract:

Background: Domestic accountability, budget transparency and public financial management (PFM) are considered vital components of good governance in developing countries. The aid modality budget support (BS) promotes these governance functions in developing countries. BS engages in political decision-making and provides financial and technical support to poverty reduction strategies of the partner countries. Nevertheless, many donors have withdrawn their support from this modality due to cases of corruption, fraud or human rights violations. This exit from BS is leaving a finance and governance vacuum in the countries. The evaluation team analyzed the consequences of terminating the use of this modality and found particularly negative effects for good governance outcomes. Methodology: The evaluation uses a qualitative (theory-based) approach consisting of a comparative case study design, which is complemented by a process-tracing approach. For the case studies, the team conducted over 100 semi-structured interviews in Malawi, Uganda, Rwanda and Zambia and used four country-specific, tailor-made budget analysis. In combination with a previous DEval evaluation synthesis on the effects of BS, the team was able to create a before-and-after comparison that yields causal effects. Main Findings: In all four countries domestic accountability and budget transparency declined if other forms of pressure are not replacing BS´s mutual accountability mechanisms. In Malawi a fraud scandal created pressure from the society and from donors so that accountability was improved. In the other countries, these pressure mechanisms were absent so that domestic accountability declined. BS enables donors to actively participate in political processes of the partner country as donors transfer funds into the treasury of the partner country and conduct a high-level political dialogue. The results confirm that the exit from BS created a governance vacuum that, if not compensated through external/internal pressure, leads to a deterioration of good governance. For example, in the case of highly aid dependent Malawi did the possibility of a relaunch of BS provide sufficient incentives to push for governance reforms. Overall the results show that the three good governance areas are negatively affected by the exit from BS. This stands in contrast to positive effects found before the exit. The team concludes that the relationship is causal, because the before-and-after comparison coherently shows that the presence of BS correlates with positive effects and the absence with negative effects. Conclusion: These findings strongly suggest that BS is an effective modality to promote governance and its abolishment is likely to cause governance disruptions. Donors and partner governments should find ways to re-engage in closely coordinated policy-based aid modalities. In addition, a coordinated and carefully managed exit-strategy should be in place before an exit from similar modalities is considered. Particularly a continued framework of mutual accountability and a high-level political dialogue should be aspired to maintain pressure and oversight that is required to achieve good governance.

Keywords: budget support, domestic accountability, public financial management and budget transparency, Sub-Sahara Africa

Procedia PDF Downloads 127
557 Acceleration of Adsorption Kinetics by Coupling Alternating Current with Adsorption Process onto Several Adsorbents

Authors: A. Kesraoui, M. Seffen

Abstract:

Applications of adsorption onto activated carbon for water treatment are well known. The process has been demonstrated to be widely effective for removing dissolved organic substances from wastewaters, but this treatment has a major drawback is the high operating cost. The main goal of our research work is to improve the retention capacity of Tunisian biomass for the depollution of industrial wastewater and retention of pollutants considered toxic. The biosorption process is based on the retention of molecules and ions onto a solid surface composed of biological materials. The evaluation of the potential use of these materials is important to propose as an alternative to the adsorption process generally expensive, used to remove organic compounds. Indeed, these materials are very abundant in nature and are low cost. Certainly, the biosorption process is effective to remove the pollutants, but it presents a slow kinetics. The improvement of the biosorption rates is a challenge to make this process competitive with respect to oxidation and adsorption onto lignocellulosic fibers. In this context, the alternating current appears as a new alternative, original and a very interesting phenomenon in the acceleration of chemical reactions. Our main goal is to increase the retention acceleration of dyes (indigo carmine, methylene blue) and phenol by using a new alternative: alternating current. The adsorption experiments have been performed in a batch reactor by adding some of the adsorbents in 150 mL of pollutants solution with the desired concentration and pH. The electrical part of the mounting comprises a current source which delivers an alternating current voltage of 2 to 15 V. It is connected to a voltmeter that allows us to read the voltage. In a 150 mL capacity cell, we plunged two zinc electrodes and the distance between two Zinc electrodes has been 4 cm. Thanks to alternating current, we have succeeded to improve the performance of activated carbon by increasing the speed of the indigo carmine adsorption process and reducing the treatment time. On the other hand, we have studied the influence of the alternating current on the biosorption rate of methylene blue onto Luffa cylindrica fibers and the hybrid material (Luffa cylindrica-ZnO). The results showed that the alternating current accelerated the biosorption rate of methylene blue onto the Luffa cylindrica and the Luffa cylindrica-ZnO hybrid material and increased the adsorbed amount of methylene blue on both adsorbents. In order to improve the removal of phenol, we performed the coupling between the alternating current and the biosorption onto two adsorbents: Luffa cylindrica and the hybrid material (Luffa cylindrica-ZnO). In fact, the alternating current has succeeded to improve the performance of adsorbents by increasing the speed of the adsorption process and the adsorption capacity and reduce the processing time.

Keywords: adsorption, alternating current, dyes, modeling

Procedia PDF Downloads 141
556 Study of Lanthanoide Organic Frameworks Properties and Synthesis: Multicomponent Ligands

Authors: Ayla Roberta Galaco, Juliana Fonseca De Lima, Osvaldo Antonio Serra

Abstract:

Coordination polymers, also known as metal-organic frameworks (MOFs) or lanthanoide organic frameworks (LOFs) have been reported due of their promising applications in gas storage, separation, catalysis, luminescence, magnetism, drug delivery, and so on. As a type of organic–inorganic hybrid materials, the properties of coordination polymers could be chosen by deliberately selecting the organic and inorganic components. LOFs have received considerable attention because of their properties such as porosity, luminescence, and magnetism. Methods such as solvothermal synthesis are important as a strategy to control the structural and morphological properties as well as the composition of the target compounds. In this work the first solvothermal synthesis was employed to obtain the compound [Y0.4,Yb0.4,Er0.2(dmf)(for)(H2O)(tft)], by using terephthalic acid (tft) and oxalic acid, decomposed in formate (for), as ligands; Yttrium, Ytterbium and, Erbium as metal centers, in DMF and water for 4 days under 160 °C. The semi-rigid terephthalic acid (dicarboxylic) coordinates with Ln3+ ions and also is possible to form a polyfunctional bridge. On the other hand, oxalate anion has no high-energy vibrational groups, which benefits the excitation of Yb3+ in upconversion process. It was observed that the compounds with water molecules in the coordination sphere of the lanthanoide ions cause lower crystalline properties and change the structure of the LOF (1D, 2D, 3D). In the FTIR, the bands at 1589 and 1500 cm-1 correspond to the asymmetric stretching vibration of –COO. The band at 1383 cm-1 is assigned to the symmetric stretching vibration of –COO. Single crystal X-ray diffraction study reveals an infinite 3D coordination framework that crystalizes in space group P21/c. The other three products, [TR(chel)(ofd)0,5(H2O)2], where TR= Eu3+, Y3, and Yb3+/Er3+ were obtained by using 1, 2-phenylenedioxydiacetic acid (ofd) and chelidonic acid (chel) as organic ligands. Thermal analysis shows that the lanthanoide organic frameworks do not collapse at temperatures below 250 °C. By the polycrystalline X-ray diffraction patterns (PXRD) it was observed that the compounds with Eu3+, Y3+, and Yb3+/Er3+ ions are isostructural. From PXRD patterns, high crystallinity can be noticed for the complexes. The final products were characterized by single X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS) and thermogravimetric analysis (TGA). The X-ray diffraction (XRD) is an effective method to investigate crystalline properties of synthesized materials. The solid crystal obtained in the synthesis show peaks at 2θ < 10°, indicating the MOF formation. The chemical composition of LOFs was also confirmed by EDS.

Keywords: isostructural, lanthanoids, lanthanoids organic frameworks (LOFs), metal organic frameworks (MOFs), thermogravimetry, X-Ray diffraction

Procedia PDF Downloads 237
555 The Effectiveness of the South African Government Theory of Expanded Public Works Program: Infrastructure

Authors: Siziwe Monica Zuma

Abstract:

The Expanded Public Works Program (EPWP) is an instrument that the South African Government uses to reduce unemployment and poverty and also stimulate economic growth. However, due to the limited budget and programs in the EPWP, the program has had challenges in reducing unemployment, poverty and stimulating economic growth. The EPWP Vuk’uphile program had positive outcomes in developing Black emerging contractors, in order for them to participate in the main stream economy far better than when the EPWP program was not introduced. The Skills component of the program particularly the EPWP Infrastructure, which is the most funded program under EPWP has had limited success in transferring appropriate skills to ensure labour participants can penetrate the labour market after participating in the EPWP. Education and skills are important attributes that can contribute to labour absorption, however, the EPWP particularly the infrastructure program needs to strengthen skills development over a longer period of time suggested a year with multi skills relevant to the labour market. Longer and more sustained employment provides a safety net and reduces poverty better that short term employment. The EPWP program can be expanded in the infrastructure sector, focusing on rural infrastructure, agricultural infrastructure, infrastructure related components like property, ownership, management, and other services. These can stimulate the Economic sector Infrastructure of EPWP, offer longer term and more sustained employment and rural enterprise development and further employment. The Expanded Public Works Program (EPWP) is an instrument that the South African Government uses to reduce unemployment and poverty and also stimulate economic growth. However, due to the limited budget and programs in the EPWP, the program has had challenges in reducing unemployment, poverty and stimulating economic growth. The EPWP Vuk’uphile program has had positive outcomes in developing Black emerging contractors, in order for them to participate in the main stream economy far better than when the EPWP program was not introduced. The Skills component of the program particularly the EPWP Infrastructure, which is the most funded program under EPWP has had limited success in transferring appropriate skills to ensure labour participants are able to penetrate the labour market after participating in the EPWP. Education and skills are important attributes that can contribute to labour absorption, however, the EPWP particularly the infrastructure program needs to strengthen skills development over a longer period of time suggested a year with multi skills relevant to the labour market. Longer and more sustained employment provides a safety net and reduces poverty better that short term employment. The EPWP program can be expanded in the infrastructure sector, focusing on rural infrastructure, agricultural infrastructure, infrastructure related components like property, ownership, management, and other services. These can stimulate the Economic sector Infrastructure of EPWP, offer longer term and more sustained employment and rural enterprise development and further employment.

Keywords: Expanded Public Works Program (EPWP), VUKÚPHILE, youth, Public Works Programs (PWP), Infrastructure Sector of EPWP (EPWP Infrastructure)

Procedia PDF Downloads 200
554 Buddhist Cognitive Behavioral Therapy to Address Depression Among Elderly Population: Multi-cultural Model of Buddhist Based Cognitive Behavioral Therapy to Address Depression Among Elderly Population

Authors: Ashoke Priyadarshana Premananda

Abstract:

As per the suggestions of previously conducted research in Counseling Psychology, the necessity of forming culture- friendly approaches has been strongly emphasized by a number of scholars in the field. In response to that, Multicultural-model of Buddhist Based Cognitive Behavioral Therapy (MMBCBT) has been formed as a culture-friendly therapeutic approach to address psychological disturbances (depression) in late adulthood. Elderly population in the world is on the rise by leaps and bounds, and forming a culture-based therapeutic model which is blended with Buddhist teachings has been the major objective of the study. Buddhist teachings and cultural applications, which were mapped onto Cognitive Behavioral Therapy (CBT) in the West, ultimately resulted in MMBCBT. Therefore, MMBCBT is a blend of cultural therapeutic techniques and the essence of certain Buddhist teachings extracted from five crucial suttas, which include CBT principles. In the process of mapping, MeghiyaSutta, GirimānandaSutta, SallekhaSutta, DvedhāvitakkaSutta, and Vitakka- SaṇṭhānaSutta have been taken into consideration mainly because of their cognitive behavioral content. The practical components of Vitakka- Saṇṭhānasutta (Aññanimittapabbaṃ) and Sallekhasutta (SallekhaPariyāya and CittuppādaPariyāya) have been used in the model while mindfulness of breathing was also carried out with the participants. Basically, multi-cultural therapeutic approaches of MMBCBT aim at modifying behavior (behavioral modification), whereas the rest is centered to the cognitive restructuring process. Therefore, MMBCBT is endowed with Behavioral Therapy (BT) and Cognitive Therapy(CT). In order to find out the validation of MMBCBT as a newly formed approach, it was then followed by mixed research (quantitative and qualitative research) with a sample selected from the elderly population following the purposive sampling technique. 40 individuals were selected from three elderly homes as per the purposive sampling technique. Elderly people identified to be depressed via Geriatric Depression Scale underwent MMBCBT for two weeks continuously while action research was being conducted simultaneously. Additionally, a Focus Group interview was carried out to support the action research. As per the research findings, people who identified depressed prior to the exposure to MMBCBT were found to be showing positive changes after they were exposed to the model. “Paired Sample t test” showed that the Multicultural Model of Buddhist based Cognitive Behavioral Therapy reduced depression of elderly people (The mean value (x̄) of the sample (level of depression) before the model was 10.7 whereas the mean value after the model was 7.5.). Most importantly, MMBCBT has been found to be effectively used with people from all walks of life despite religious diversities.

Keywords: buddhist psychotherapy, cognitive behavioral therapy in buddhism, counseling in cultural context, gerontology, and buddhism

Procedia PDF Downloads 93
553 Oxidative Damage to Lipids, Proteins, and DNA during Differentiation of Mesenchymal Stem Cells Derived from Umbilical Cord into Biologically Active Hepatocytes

Authors: Abdolamir Allameh, Shahnaz Esmaeili, Mina Allameh, Safoura Khajeniazi

Abstract:

Stem cells with therapeutic applications can be isolated from human placenta/umblical cord blood (UCB) as well as the cord tissue (UC). Stem cells in culture are vulnerable to oxidative stress, particularly when subjected to differentiation process. The aim of this study was to examine the chnages in the rate of oxidation that occurs to cellular macromolecules during hepatic differentiation of mononuclear cells (MSCs). In addition, the impact of the hepatic differentiation process of MSC on cellular and biological activity of the cells will be undertaken. For this purpose, first mononuclear cells (MNCs) were isolated from human UCB which was obtained from a healthy full-term infant. The cells were cultured at a density of 3×10⁵ cells/cm² in DMEM- low-glucose culture media supplemented with 20% FBS, 2 mM L-glutamine, 100 μg/ml streptomycin and 100 U/ml penicillin. Cell cultures were then incubated at 37°C in a humidified 5% CO₂ incubator. After removing non-adherent cells by replacing culture medium, fibroblast-like adherent cells were resuspended in 0.25% trypsin-EDTA and plated in 25 cm² flasks (1×10⁴/ml). Characterization of the MSCs was routinely done by observing their morphology and growth curve. MSCs were subjected to a 2-step hepatocyte differentiation protocol in presence of hepatocyte growth factor (HGF), dexamethazone (DEX) and oncostatin M (OSM). The hepatocyte-like cells derived from MSCs were checked every week for 3 weeks for changes in lipid peroxidation, protein carbonyl formation and DNA oxidation i.e., 8-hydroxy-2'-deoxyguanosine (8-OH-dG) assay. During the 3-week differentiation process of MSCs to hepatocyte-like cells we found that expression liver-specific markers such as albumin, was associated with increased levels of lipid peroxidation and protein carbonyl formation. Whereas, undifferentiated MSCs has relatively low levels of lipid peroxidation products. There was a significant increase ( p < 0.05) in lipid peroxidation products in hepatocytes on days 7, 14, and 21 of differentiation. Likewise, the level of protein carbonyls in the cells was elevated during the differentiation. The level of protein carbonyls measured in hepatocyte-like cells obtained 3 weeks after differentiation induction was estimated to be ~6 fold higher compared to cells recovered on day 7 of differentiation. On the contrary, there was a small but significant decrease in DNA damage marker (8-OH-dG) in hepatocytes recovered 3 weeks after differentiation onset. The level of 8-OHdG which was in consistent with formation of reactive oxygen species (ROS). In conclusion, this data suggest that despite the elevation in oxidation of lipid and protein molecules during hepatocyte development, the cells were normal in terms of DNA integrity, morphology, and biologically activity.

Keywords: adult stem cells, DNA integrity, free radicals, hepatic differentiation

Procedia PDF Downloads 132
552 Intelligent Control of Agricultural Farms, Gardens, Greenhouses, Livestock

Authors: Vahid Bairami Rad

Abstract:

The intelligentization of agricultural fields can control the temperature, humidity, and variables affecting the growth of agricultural products online and on a mobile phone or computer. Smarting agricultural fields and gardens is one of the best and best ways to optimize agricultural equipment and has a 100 percent direct effect on the growth of plants and agricultural products and farms. Smart farms are the topic that we are going to discuss today, the Internet of Things and artificial intelligence. Agriculture is becoming smarter every day. From large industrial operations to individuals growing organic produce locally, technology is at the forefront of reducing costs, improving results and ensuring optimal delivery to market. A key element to having a smart agriculture is the use of useful data. Modern farmers have more tools to collect intelligent data than in previous years. Data related to soil chemistry also allows people to make informed decisions about fertilizing farmland. Moisture meter sensors and accurate irrigation controllers have made the irrigation processes to be optimized and at the same time reduce the cost of water consumption. Drones can apply pesticides precisely on the desired point. Automated harvesting machines navigate crop fields based on position and capacity sensors. The list goes on. Almost any process related to agriculture can use sensors that collect data to optimize existing processes and make informed decisions. The Internet of Things (IoT) is at the center of this great transformation. Internet of Things hardware has grown and developed rapidly to provide low-cost sensors for people's needs. These sensors are embedded in IoT devices with a battery and can be evaluated over the years and have access to a low-power and cost-effective mobile network. IoT device management platforms have also evolved rapidly and can now be used securely and manage existing devices at scale. IoT cloud services also provide a set of application enablement services that can be easily used by developers and allow them to build application business logic. Focus on yourself. These development processes have created powerful and new applications in the field of Internet of Things, and these programs can be used in various industries such as agriculture and building smart farms. But the question is, what makes today's farms truly smart farms? Let us put this question in another way. When will the technologies associated with smart farms reach the point where the range of intelligence they provide can exceed the intelligence of experienced and professional farmers?

Keywords: food security, IoT automation, wireless communication, hybrid lifestyle, arduino Uno

Procedia PDF Downloads 35
551 Sustainability in Higher Education: A Case of Transition Management from a Private University in Turkey (Ongoing Study)

Authors: Ayse Collins

Abstract:

The Agenda 2030 puts Higher Education Institutions (HEIs) in the situation where they should emphasize ways to promote sustainability accordingly. However, it is still unclear: a) how sustainability is understood, and b) which actions have been taken in both discourse and practice by HEIs regarding the three pillars of sustainability, society, environment, and economy. There are models of sustainable universities developed by different authors from different countries; For Example, The Global Reporting Initiative (GRI) methodology which offers a variety of indicators to diagnose performance. However, these models have never been developed for universities in particular. Any model, in this sense, cannot be completed adequately without defining the appropriate tools to measure, analyze and control the performance of initiatives. There is a need to conduct researches in different universities from different countries to understand where we stand in terms of sustainable higher education. Therefore, this study aims at exploring the actions taken by a university in Ankara, Turkey, since Agenda 2030 should consider localizing its objectives and targets according to a certain geography. This university just announced 2021-2022 as “Sustainability Year.” Therefore, this research is a multi-methodology longitudinal study and uses the theoretical framework of the organization and transition management (TM). It is designed to examine the activities as being strategic, tactical, operational, and reflexive in nature and covers the six main aspects: academic community, administrative staff, operations and services, teaching, research, and extension. The preliminary research will answer the role of the top university governance, perception of the stakeholders (students, instructors, administrative and support staff) regarding sustainability, and the level of achievement at the mid-evaluation and final, end of year evaluation. TM Theory is a multi-scale, multi-actor, process-oriented approach with the analytical framework to explore and promote change in social systems. Therefore, the stages and respective methodology for collecting data in this research is: Pre-development Stage: a) semi-structured interviews with university governance, c) open-ended survey with faculty, students, and administrative staff d) Semi-structured interviews with support staff, and e) analysis of current secondary data for sustainability. Take-off Stage: a) semi-structured interviews with university governance, faculty, students, administrative and support staff, b) analysis of secondary data. Breakthrough stabilization a) survey with all stakeholders at the university, b) secondary data analysis by using selected indicators for the first sustainability report for universities The findings from the predevelopment stage highlight how stakeholders, coming from different faculties, different disciplines with different identities and characteristics, face the sustainability challenge differently. Though similar sustainable development goals ((social, environmental, and economic) are set in the institution, there are differences across disciplines and among different stakeholders, which need to be considered to reach the optimum goal. It is believed that the results will help changes in HEIs organizational culture to embed sustainability values in their strategic planning, academic and managerial work by putting enough time and resources to be successful in coping with sustainability.

Keywords: higher education, sustainability, sustainability auditing, transition management

Procedia PDF Downloads 95
550 Escaping Domestic Violence in Time of Conflict: The Ways Female Refugees Decide to Flee

Authors: Zofia Wlodarczyk

Abstract:

I study the experiences of domestic violence survivors who flee their countries of origin in times of political conflict using insight and evidence from forty-five biographical interviews with female Chechen refugees and twelve refugee resettlement professionals in Poland. Both refugees and women are often described as having less agency—that is, they lack the power to decide to migrate – refugees less than economic migrants and women less than men. In this paper, I focus on how female refugees who have been victims of domestic violence make decisions about leaving their countries of origin during times of political conflict. I use several existing migration theories to trace how the migration experience of these women is shaped by dynamics at different levels of society: the macro level, the meso level and the micro level. At the macro level of analysis, I find that political conflict can be both a source of and an escape from domestic violence. Ongoing conflict can strengthen the patriarchal cultural norms, increase violence and constrain women’s choices when it comes to marriage. However, political conflict can also destabilize families and make pathways for women to escape. At the meso level I demonstrate that other political migrants and institutions that emerge due to politically triggered migration can guide those fleeing domestic violence. Finally, at the micro level, I show that family dynamics often force domestic abuse survivors to make their decision to escape alone or with the support of only the most trusted female relatives. Taken together, my analyses show that we cannot look solely at one level of society when describing decision-making processes of women fleeing domestic violence. Conflict-related micro, meso and macro forces interact with and influence each other: on the one hand, strengthening an abusive trap, and on the other hand, opening a door to escape. This study builds upon several theoretical and empirical debates. First, it expands theories of migration by incorporating both refugee and gender perspectives. Few social scientists have used the migration theory framework to discuss the unique circumstances of refugee flows. Those who have mainly focus on “political” migrants, a designation that frequently fails to account for gender, does not incorporate individuals fleeing gender-based violence, including domestic-violence victims. The study also enriches migration scholarship, typically focused on the US and Western-European context, with research from Eastern Europe and Caucasus. Moreover, it contributes to the literature on the changing roles of gender in the context of migration. I argue that understanding how gender roles and hierarchies influence the pre-migration stage of female refugees is crucial, as it may have implications for policy-making efforts in host countries that recognize the asylum claims of those fleeing domestic violence. This study also engages in debates about asylum and refugee law. Domestic violence is normatively and often legally considered an individual-level problem whereas political persecution is recognized as a structural or societal level issue. My study challenges these notions by showing how the migration triggered by domestic violence is closely intertwined with politically motivated refuge.

Keywords: AGENCY, DOMESTIC VIOLENCE, FEMALE REFUGEES, POLITICAL REFUGE, SOCIAL NETWORKS

Procedia PDF Downloads 149
549 A Resilience-Based Approach for Assessing Social Vulnerability in New Zealand's Coastal Areas

Authors: Javad Jozaei, Rob G. Bell, Paula Blackett, Scott A. Stephens

Abstract:

In the last few decades, Social Vulnerability Assessment (SVA) has been a favoured means in evaluating the susceptibility of social systems to drivers of change, including climate change and natural disasters. However, the application of SVA to inform responsive and practical strategies to deal with uncertain climate change impacts has always been challenging, and typically agencies resort back to conventional risk/vulnerability assessment. These challenges include complex nature of social vulnerability concepts which influence its applicability, complications in identifying and measuring social vulnerability determinants, the transitory social dynamics in a changing environment, and unpredictability of the scenarios of change that impacts the regime of vulnerability (including contention of when these impacts might emerge). Research suggests that the conventional quantitative approaches in SVA could not appropriately address these problems; hence, the outcomes could potentially be misleading and not fit for addressing the ongoing uncertain rise in risk. The second phase of New Zealand’s Resilience to Nature’s Challenges (RNC2) is developing a forward-looking vulnerability assessment framework and methodology that informs the decision-making and policy development in dealing with the changing coastal systems and accounts for complex dynamics of New Zealand’s coastal systems (including socio-economic, environmental and cultural). Also, RNC2 requires the new methodology to consider plausible drivers of incremental and unknowable changes, create mechanisms to enhance social and community resilience; and fits the New Zealand’s multi-layer governance system. This paper aims to analyse the conventional approaches and methodologies in SVA and offer recommendations for more responsive approaches that inform adaptive decision-making and policy development in practice. The research adopts a qualitative research design to examine different aspects of the conventional SVA processes, and the methods to achieve the research objectives include a systematic review of the literature and case study methods. We found that the conventional quantitative, reductionist and deterministic mindset in the SVA processes -with a focus the impacts of rapid stressors (i.e. tsunamis, floods)- show some deficiencies to account for complex dynamics of social-ecological systems (SES), and the uncertain, long-term impacts of incremental drivers. The paper will focus on addressing the links between resilience and vulnerability; and suggests how resilience theory and its underpinning notions such as the adaptive cycle, panarchy, and system transformability could address these issues, therefore, influence the perception of vulnerability regime and its assessment processes. In this regard, it will be argued that how a shift of paradigm from ‘specific resilience’, which focuses on adaptive capacity associated with the notion of ‘bouncing back’, to ‘general resilience’, which accounts for system transformability, regime shift, ‘bouncing forward’, can deliver more effective strategies in an era characterised by ongoing change and deep uncertainty.

Keywords: complexity, social vulnerability, resilience, transformation, uncertain risks

Procedia PDF Downloads 75
548 Effect of Plant Growth Regulators on in vitro Biosynthesis of Antioxidative Compounds in Callus Culture and Regenerated Plantlets Derived from Taraxacum officinale

Authors: Neha Sahu, Awantika Singh, Brijesh Kumar, K. R. Arya

Abstract:

Taraxacum officinale Weber or dandelion (Asteraceae) is an important Indian traditional herb used to treat liver detoxification, digestive problems, spleen, hepatic and kidney disorders, etc. The plant is well known to possess important phenolic and flavonoids to serve as a potential source of antioxidative and chemoprotective agents. Biosynthesis of bioactive compounds through in vitro cultures is a requisite for natural resource conservation and to provide an alternative source for pharmaceutical applications. Thus an efficient and reproducible protocol was developed for in vitro biosynthesis of bioactive antioxidative compounds from leaf derived callus and in vitro regenerated cultures of Taraxacum officinale using MS media fortified with various combinations of auxins and cytokinins. MS media containing 0.25 mg/l 2, 4-D (2, 4-Dichloro phenoxyacetic acid) with 0.05 mg/l 2-iP [N6-(2-Isopentenyl adenine)] was found as an effective combination for the establishment of callus with 92 % callus induction frequency. Moreover, 2.5 mg/l NAA (α-Naphthalene acetic acid) with 0.5 mg/l BAP (6-Benzyl aminopurine) and 1.5 mg/l NAA showed the optimal response for in vitro plant regeneration with 80 % regeneration frequency and rooting respectively. In vitro regenerated plantlets were further transferred to soil and acclimatized. Quantitative variability of accumulated bioactive compounds in cultures (in vitro callus, plantlets and acclimatized) were determined through UPLC-MS/MS (ultra-performance liquid chromatography-triple quadrupole-linear ion trap mass spectrometry) and compared with wild plants. The phytochemical determination of in vitro and wild grown samples showed the accumulation of 6 compounds. In in vitro callus cultures and regenerated plantlets, two major antioxidative compounds i.e. chlorogenic acid (14950.0 µg/g and 4086.67 µg/g) and umbelliferone (10400.00 µg/g and 2541.67 µg/g) were found respectively. Scopoletin was found to be highest in vitro regenerated plants (83.11 µg/g) as compared to wild plants (52.75 µg/g). Notably, scopoletin is not detected in callus and acclimatized plants, but quinic acid (6433.33 µg/g) and protocatechuic acid (92.33 µg/g) were accumulated at the highest level in acclimatized plants as compared to other samples. Wild grown plants contained highest content (948.33 µg/g) of flavonoid glycoside i.e. luteolin-7-O-glucoside. Our data suggests that in vitro callus and regenerated plants biosynthesized higher content of antioxidative compounds in controlled conditions when compared to wild grown plants. These standardized cultural conditions may be explored as a sustainable source of plant materials for enhanced production and adequate supply of oxidative polyphenols.

Keywords: anti-oxidative compounds, in vitro cultures, Taraxacum officinale, UPLC-MS/MS

Procedia PDF Downloads 185
547 Marine Environmental Monitoring Using an Open Source Autonomous Marine Surface Vehicle

Authors: U. Pruthviraj, Praveen Kumar R. A. K. Athul, K. V. Gangadharan, S. Rao Shrikantha

Abstract:

An open source based autonomous unmanned marine surface vehicle (UMSV) is developed for some of the marine applications such as pollution control, environmental monitoring and thermal imaging. A double rotomoulded hull boat is deployed which is rugged, tough, quick to deploy and moves faster. It is suitable for environmental monitoring, and it is designed for easy maintenance. A 2HP electric outboard marine motor is used which is powered by a lithium-ion battery and can also be charged from a solar charger. All connections are completely waterproof to IP67 ratings. In full throttle speed, the marine motor is capable of up to 7 kmph. The motor is integrated with an open source based controller using cortex M4F for adjusting the direction of the motor. This UMSV can be operated by three modes: semi-autonomous, manual and fully automated. One of the channels of a 2.4GHz radio link 8 channel transmitter is used for toggling between different modes of the USMV. In this electric outboard marine motor an on board GPS system has been fitted to find the range and GPS positioning. The entire system can be assembled in the field in less than 10 minutes. A Flir Lepton thermal camera core, is integrated with a 64-bit quad-core Linux based open source processor, facilitating real-time capturing of thermal images and the results are stored in a micro SD card which is a data storage device for the system. The thermal camera is interfaced to an open source processor through SPI protocol. These thermal images are used for finding oil spills and to look for people who are drowning at low visibility during the night time. A Real Time clock (RTC) module is attached with the battery to provide the date and time of thermal images captured. For the live video feed, a 900MHz long range video transmitter and receiver is setup by which from a higher power output a longer range of 40miles has been achieved. A Multi-parameter probe is used to measure the following parameters: conductivity, salinity, resistivity, density, dissolved oxygen content, ORP (Oxidation-Reduction Potential), pH level, temperature, water level and pressure (absolute).The maximum pressure it can withstand 160 psi, up to 100m. This work represents a field demonstration of an open source based autonomous navigation system for a marine surface vehicle.

Keywords: open source, autonomous navigation, environmental monitoring, UMSV, outboard motor, multi-parameter probe

Procedia PDF Downloads 219
546 A New Approach for Preparation of Super Absorbent Polymers: In-Situ Surface Cross-Linking

Authors: Reyhan Özdoğan, Mithat Çelebi, Özgür Ceylan, Mehmet Arif Kaya

Abstract:

Super absorbent polymers (SAPs) are defined as materials that can absorb huge amount of water or aqueous solution in comparison to their own mass and retain in their lightly cross-linked structure. SAPs were produced from water soluble monomers via polymerization subsequently controlled crosslinking. SAPs are generally used for water absorbing applications such as baby diapers, patient or elder pads and other hygienic product industries. Crosslinking density (CD) of SAP structure is an essential factor for water absortion capacity (WAC). Low internal CD leads to high WAC values and vice versa. However, SAPs have low CD and high swelling capacities and tend to disintegrate when pressure is applied upon them, so SAPs under load cannot absorb liquids effectively. In order to prevent this undesired situation and to obtain suitable SAP structures having high swelling capacity and ability to work under load, surface crosslinking can be the answer. In industry, these superabsorbent gels are mostly produced via solution polymerization and then they need to be dried, grinded, sized, post polymerized and finally surface croslinked (involves spraying of a crosslinking solution onto dried and grinded SAP particles, and then curing by heat). It can easily be seen that these steps are time consuming and should be handled carefully for the desired final product. If we could synthesize desired final SAPs using less processes it will help reducing time and production costs which are very important for any industries. In this study, synthesis of SAPs were achieved successfully by inverse suspension (Pickering type) polymerization and subsequently in-situ surface cross-linking via using proper surfactants in high boiling point solvents. Our one-pot synthesis of surface cross-linked SAPs invovles only one-step for preparation, thus it can be said that this technique exhibits more preferable characteristic for the industry in comparison to conventional methods due to its one-step easy process. Effects of different surface crosslinking agents onto properties of poly(acrylic acid-co-sodium acrylate) based SAPs are investigated. Surface crosslink degrees are evaluated by swelling under load (SUL) test. It was determined water absorption capacities of obtained SAPs decrease with the increasing surface crosslink density while their mechanic properties are improved.

Keywords: inverse suspension polymerization, polyacrylic acid, super absorbent polymers (SAPs), surface crosslinking, sodium polyacrylate

Procedia PDF Downloads 308
545 Investigation of Mass Transfer for RPB Distillation at High Pressure

Authors: Amiza Surmi, Azmi Shariff, Sow Mun Serene Lock

Abstract:

In recent decades, there has been a significant emphasis on the pivotal role of Rotating Packed Beds (RPBs) in absorption processes, encompassing the removal of Volatile Organic Compounds (VOCs) from groundwater, deaeration, CO2 absorption, desulfurization, and similar critical applications. The primary focus is elevating mass transfer rates, enhancing separation efficiency, curbing power consumption, and mitigating pressure drops. Additionally, substantial efforts have been invested in exploring the adaptation of RPB technology for offshore deployment. This comprehensive study delves into the intricacies of nitrogen removal under low temperature and high-pressure conditions, employing the high gravity principle via innovative RPB distillation concept with a specific emphasis on optimizing mass transfer. Based on the author's knowledge and comprehensive research, no cryogenic experimental testing was conducted to remove nitrogen via RPB. The research identifies pivotal process control factors through meticulous experimental testing, with pressure, reflux ratio, and reboil ratio emerging as critical determinants in achieving the desired separation performance. The results are remarkable, with nitrogen removal reaching less than one mole% in the Liquefied Natural Gas (LNG) product and less than three moles% methane in the nitrogen-rich gas stream. The study further unveils the mass transfer coefficient, revealing a noteworthy trend of decreasing Number of Transfer Units (NTU) and Area of Transfer Units (ATU) as the rotational speed escalates. Notably, the condenser and reboiler impose varying demands based on the operating pressure, with lower pressures at 12 bar requiring a more substantial duty than the 15-bar operation of the RPB. In pursuit of optimal energy efficiency, a meticulous sensitivity analysis is conducted, pinpointing the ideal combination of pressure and rotating speed that minimizes overall energy consumption. These findings underscore the efficiency of the RPB distillation approach in effecting efficient separation, even when operating under the challenging conditions of low temperature and high pressure. This achievement is attributed to a rigorous process control framework that diligently manages the operational pressure and temperature profile of the RPB. Nonetheless, the study's conclusions point towards the need for further research to address potential scaling challenges and associated risks, paving the way for the industrial implementation of this transformative technology.

Keywords: mass transfer coefficient, nitrogen removal, liquefaction, rotating packed bed

Procedia PDF Downloads 32
544 The Impact of a Simulated Teaching Intervention on Preservice Teachers’ Sense of Professional Identity

Authors: Jade V. Rushby, Tony Loughland, Tracy L. Durksen, Hoa Nguyen, Robert M. Klassen

Abstract:

This paper reports a study investigating the development and implementation of an online multi-session ‘scenario-based learning’ (SBL) program administered to preservice teachers in Australia. The transition from initial teacher education to the teaching profession can present numerous cognitive and psychological challenges for early career teachers. Therefore, the identification of additional supports, such as scenario-based learning, that can supplement existing teacher education programs may help preservice teachers to feel more confident and prepared for the realities and complexities of teaching. Scenario-based learning is grounded in situated learning theory which holds that learning is most powerful when it is embedded within its authentic context. SBL exposes participants to complex and realistic workplace situations in a supportive environment and has been used extensively to help prepare students in other professions, such as legal and medical education. However, comparatively limited attention has been paid to investigating the effects of SBL in teacher education. In the present study, the SBL intervention provided participants with the opportunity to virtually engage with school-based scenarios, reflect on how they might respond to a series of plausible response options, and receive real-time feedback from experienced educators. The development process involved several stages, including collaboration with experienced educators to determine the scenario content based on ‘critical incidents’ they had encountered during their teaching careers, the establishment of the scoring key, the development of the expert feedback, and an extensive review process to refine the program content. The 4-part SBL program focused on areas that can be challenging in the beginning stages of a teaching career, including managing student behaviour and workload, differentiating the curriculum, and building relationships with colleagues, parents, and the community. Results from prior studies implemented by the research group using a similar 4-part format have shown a statistically significant increase in preservice teachers’ self-efficacy and classroom readiness from the pre-test to the final post-test. In the current research, professional teaching identity - incorporating self-efficacy, motivation, self-image, satisfaction, and commitment to teaching - was measured over six weeks at multiple time points: before, during, and after the 4-part scenario-based learning program. Analyses included latent growth curve modelling to assess the trajectory of change in the outcome variables throughout the intervention. The paper outlines (1) the theoretical underpinnings of SBL, (2) the development of the SBL program and methodology, and (3) the results from the study, including the impact of the SBL program on aspects of participating preservice teachers’ professional identity. The study shows how SBL interventions can be implemented alongside the initial teacher education curriculum to help prepare preservice teachers for the transition from student to teacher.

Keywords: classroom simulations, e-learning, initial teacher education, preservice teachers, professional learning, professional teaching identity, scenario-based learning, teacher development

Procedia PDF Downloads 57
543 Dual-Layer Microporous Layer of Gas Diffusion Layer for Proton Exchange Membrane Fuel Cells under Various RH Conditions

Authors: Grigoria Athanasaki, Veerarajan Vimala, A. M. Kannan, Louis Cindrella

Abstract:

Energy usage has been increased throughout the years, leading to severe environmental impacts. Since the majority of the energy is currently produced from fossil fuels, there is a global need for clean energy solutions. Proton Exchange Membrane Fuel Cells (PEMFCs) offer a very promising solution for transportation applications because of their solid configuration and low temperature operations, which allows them to start quickly. One of the main components of PEMFCs is the Gas Diffusion Layer (GDL), which manages water and gas transport and shows direct influence on the fuel cell performance. In this work, a novel dual-layer GDL with gradient porosity was prepared, using polyethylene glycol (PEG) as pore former, to improve the gas diffusion and water management in the system. The microporous layer (MPL) of the fabricated GDL consists of carbon powder PUREBLACK, sodium dodecyl sulfate as a surfactant, 34% wt. PTFE and the gradient porosity was created by applying one layer using 30% wt. PEG on the carbon substrate, followed by a second layer without using any pore former. The total carbon loading of the microporous layer is ~ 3 mg.cm-2. For the assembly of the catalyst layer, Nafion membrane (Ion Power, Nafion Membrane NR211) and Pt/C electrocatalyst (46.1% wt.) were used. The catalyst ink was deposited on the membrane via microspraying technique. The Pt loading is ~ 0.4 mg.cm-2, and the active area is 5 cm2. The sample was ex-situ characterized via wetting angle measurement, Scanning Electron Microscopy (SEM), and Pore Size Distribution (PSD) to evaluate its characteristics. Furthermore, for the performance evaluation in-situ characterization via Fuel Cell Testing using H2/O2 and H2/air as reactants, under 50, 60, 80, and 100% relative humidity (RH), took place. The results were compared to a single layer GDL, fabricated with the same carbon powder and loading as the dual layer GDL, and a commercially available GDL with MPL (AvCarb2120). The findings reveal high hydrophobic properties of the microporous layer of the GDL for both PUREBLACK based samples, while the commercial GDL demonstrates hydrophilic behavior. The dual layer GDL shows high and stable fuel cell performance under all the RH conditions, whereas the single layer manifests a drop in performance at high RH in both oxygen and air, caused by catalyst flooding. The commercial GDL shows very low and unstable performance, possibly because of its hydrophilic character and thinner microporous layer. In conclusion, the dual layer GDL with PEG appears to have improved gas diffusion and water management in the fuel cell system. Due to its increasing porosity from the catalyst layer to the carbon substrate, it allows easier access of the reactant gases from the flow channels to the catalyst layer, and more efficient water removal from the catalyst layer, leading to higher performance and stability.

Keywords: gas diffusion layer, microporous layer, proton exchange membrane fuel cells, relative humidity

Procedia PDF Downloads 111
542 A Stochastic Vehicle Routing Problem with Ordered Customers and Collection of Two Similar Products

Authors: Epaminondas G. Kyriakidis, Theodosis D. Dimitrakos, Constantinos C. Karamatsoukis

Abstract:

The vehicle routing problem (VRP) is a well-known problem in Operations Research and has been widely studied during the last fifty-five years. The context of the VRP is that of delivering or collecting products to or from customers who are scattered in a geographical area and have placed orders for these products. A vehicle or a fleet of vehicles start their routes from a depot and visit the customers in order to satisfy their demands. Special attention has been given to the capacitated VRP in which the vehicles have limited carrying capacity for the goods that are delivered or collected. In the present work, we present a specific capacitated stochastic vehicle routing problem which has many realistic applications. We develop and analyze a mathematical model for a specific vehicle routing problem in which a vehicle starts its route from a depot and visits N customers according to a particular sequence in order to collect from them two similar but not identical products. We name these products, product 1 and product 2. Each customer possesses items either of product 1 or product 2 with known probabilities. The number of the items of product 1 or product 2 that each customer possesses is a discrete random variable with known distribution. The actual quantity and the actual type of product that each customer possesses are revealed only when the vehicle arrives at the customer’s site. It is assumed that the vehicle has two compartments. We name these compartments, compartment 1 and compartment 2. It is assumed that compartment 1 is suitable for loading product 1 and compartment 2 is suitable for loading product 2. However, it is permitted to load items of product 1 into compartment 2 and items of product 2 into compartment 1. These actions cause costs that are due to extra labor. The vehicle is allowed during its route to return to the depot to unload the items of both products. The travel costs between consecutive customers and the travel costs between the customers and the depot are known. The objective is to find the optimal routing strategy, i.e. the routing strategy that minimizes the total expected cost among all possible strategies for servicing all customers. It is possible to develop a suitable dynamic programming algorithm for the determination of the optimal routing strategy. It is also possible to prove that the optimal routing strategy has a specific threshold-type strategy. Specifically, it is shown that for each customer the optimal actions are characterized by some critical integers. This structural result enables us to design a special-purpose dynamic programming algorithm that operates only over these strategies having this structural property. Extensive numerical results provide strong evidence that the special-purpose dynamic programming algorithm is considerably more efficient than the initial dynamic programming algorithm. Furthermore, if we consider the same problem without the assumption that the customers are ordered, numerical experiments indicate that the optimal routing strategy can be computed if N is smaller or equal to eight.

Keywords: dynamic programming, similar products, stochastic demands, stochastic preferences, vehicle routing problem

Procedia PDF Downloads 241
541 Cytotoxic Effect of Biologically Transformed Propolis on HCT-116 Human Colon Cancer Cells

Authors: N. Selvi Gunel, L. M. Oktay, H. Memmedov, B. Durmaz, H. Kalkan Yildirim, E. Yildirim Sozmen

Abstract:

Object: Propolis which consists of compounds that are accepted as antioxidant, antimicrobial, antiseptic, antibacterial, anti-inflammatory, anti-mutagenic, immune-modulator and cytotoxic, is frequently used in current therapeutic applications. However, some of them result in allergic side effects, causing consumption to be restricted. Previously our group has succeeded in producing a new biotechnological product which was less allergenic. In this study, we purpose to optimize production conditions of this biologically-transformed propolis and determine the cytotoxic effects of obtained new products on colon cancer cell line (HCT-116). Method: Firstly, solid propolis samples were dissolved in water after weighing, grinding and sizing (sieve-35mesh) and applied 40 kHz/10 min ultrasonication. Samples were prepared according to inoculation with Lactobacillus plantarum in two different proportions (2.5% and 3.5%). Chromatographic analyzes of propolis were performed by UPLC-MS/MS (Waters, Milford, MA) system. Results were analysed by UPLC-MS/MS system MassLynx™ 4.1 software. HCT-116 cells were treated with propolis examples at 25-1000 µg/ml concentrations and cytotoxicity were measured by using WST-8 assay at 24, 48, and 72 hours. Samples with biological transformation were compared with the non-transformed control group samples. Our experiment groups were formed as follows: untreated (group 1), propolis dissolved in water ultrasonicated at 40 kHz/10 min (group 2), propolis dissolved in water ultrasonicated at 40 kHz/10 min and inoculated 2.5% L. plantarum L1 strain (group 3), propolis dissolved in water ultrasonicated at 40 kHz/10 min and inoculated 3.5% L. plantarum L3 strain (group 4). Obtained data were calculated with Graphpad Software V5 and analyzed by two-way ANOVA test followed by Bonferroni test. Result: As a result of our study, the cytotoxic effect of propolis samples on HCT-116 cells was evaluated. There was a 7.21 fold increase in group 3 compared to group 2 in the concentration of 1000 µg/ml, and it was a 6.66 fold increase in group 3 compared to group 1 at the end of 24 hours. At the end of 48 hours, in the concentration of 500 µg/ml, it was determined 4.7 fold increase in group 4 compared to group 3. At the same time, in the concentration of 750 µg/ml it was determined 2.01 fold increase in group 4 compared to group 3 and in the same concentration, it was determined 3.1 fold increase in group 4 compared to group 2. Also, at the 72 hours, in the concentration of 750 µg/ml, it was determined 2.42 fold increase in group 3 according to group 2 and in the same time, in the concentration of 1000 µg/ml, it was determined 2.13 fold increase in group 4 according to group 2. According to cytotoxicity results, the group which were ultrasonicated at 40 kHz/10min and inoculated 3.5% L. plantarum L3-strain had a higher cytotoxic effect. Conclusion: It is known that bioavailability of propolis is halved in six months. The data obtained from our results indicated that biologically-transformed propolis had more cytotoxic effect than non-transformed group on colon cancer cells. Consequently, we suggested that L. plantarum-transformation provides both reduction of allergenicity and extension of bioavailability period by enhancing healthful polyphenols.

Keywords: bio-transformation, propolis, colon cancer, cytotoxicity

Procedia PDF Downloads 121
540 Multi-Labeled Aromatic Medicinal Plant Image Classification Using Deep Learning

Authors: Tsega Asresa, Getahun Tigistu, Melaku Bayih

Abstract:

Computer vision is a subfield of artificial intelligence that allows computers and systems to extract meaning from digital images and video. It is used in a wide range of fields of study, including self-driving cars, video surveillance, medical diagnosis, manufacturing, law, agriculture, quality control, health care, facial recognition, and military applications. Aromatic medicinal plants are botanical raw materials used in cosmetics, medicines, health foods, essential oils, decoration, cleaning, and other natural health products for therapeutic and Aromatic culinary purposes. These plants and their products not only serve as a valuable source of income for farmers and entrepreneurs but also going to export for valuable foreign currency exchange. In Ethiopia, there is a lack of technologies for the classification and identification of Aromatic medicinal plant parts and disease type cured by aromatic medicinal plants. Farmers, industry personnel, academicians, and pharmacists find it difficult to identify plant parts and disease types cured by plants before ingredient extraction in the laboratory. Manual plant identification is a time-consuming, labor-intensive, and lengthy process. To alleviate these challenges, few studies have been conducted in the area to address these issues. One way to overcome these problems is to develop a deep learning model for efficient identification of Aromatic medicinal plant parts with their corresponding disease type. The objective of the proposed study is to identify the aromatic medicinal plant parts and their disease type classification using computer vision technology. Therefore, this research initiated a model for the classification of aromatic medicinal plant parts and their disease type by exploring computer vision technology. Morphological characteristics are still the most important tools for the identification of plants. Leaves are the most widely used parts of plants besides roots, flowers, fruits, and latex. For this study, the researcher used RGB leaf images with a size of 128x128 x3. In this study, the researchers trained five cutting-edge models: convolutional neural network, Inception V3, Residual Neural Network, Mobile Network, and Visual Geometry Group. Those models were chosen after a comprehensive review of the best-performing models. The 80/20 percentage split is used to evaluate the model, and classification metrics are used to compare models. The pre-trained Inception V3 model outperforms well, with training and validation accuracy of 99.8% and 98.7%, respectively.

Keywords: aromatic medicinal plant, computer vision, convolutional neural network, deep learning, plant classification, residual neural network

Procedia PDF Downloads 159
539 A Comprehensive Finite Element Model for Incremental Launching of Bridges: Optimizing Construction and Design

Authors: Mohammad Bagher Anvari, Arman Shojaei

Abstract:

Incremental launching, a widely adopted bridge erection technique, offers numerous advantages for bridge designers. However, accurately simulating and modeling the dynamic behavior of the bridge during each step of the launching process proves to be tedious and time-consuming. The perpetual variation of internal forces within the deck during construction stages adds complexity, exacerbated further by considerations of other load cases, such as support settlements and temperature effects. As a result, there is an urgent need for a reliable, simple, economical, and fast algorithmic solution to model bridge construction stages effectively. This paper presents a novel Finite Element (FE) model that focuses on studying the static behavior of bridges during the launching process. Additionally, a simple method is introduced to normalize all quantities in the problem. The new FE model overcomes the limitations of previous models, enabling the simulation of all stages of launching, which conventional models fail to achieve due to underlying assumptions. By leveraging the results obtained from the new FE model, this study proposes solutions to improve the accuracy of conventional models, particularly for the initial stages of bridge construction that have been neglected in previous research. The research highlights the critical role played by the first span of the bridge during the initial stages, a factor often overlooked in existing studies. Furthermore, a new and simplified model termed the "semi-infinite beam" model, is developed to address this oversight. By utilizing this model alongside a simple optimization approach, optimal values for launching nose specifications are derived. The practical applications of this study extend to optimizing the nose-deck system of incrementally launched bridges, providing valuable insights for practical usage. In conclusion, this paper introduces a comprehensive Finite Element model for studying the static behavior of bridges during incremental launching. The proposed model addresses limitations found in previous approaches and offers practical solutions to enhance accuracy. The study emphasizes the importance of considering the initial stages and introduces the "semi-infinite beam" model. Through the developed model and optimization approach, optimal specifications for launching nose configurations are determined. This research holds significant practical implications and contributes to the optimization of incrementally launched bridges, benefiting both the construction industry and bridge designers.

Keywords: incremental launching, bridge construction, finite element model, optimization

Procedia PDF Downloads 76
538 A Mixed Method Approach for Modeling Entry Capacity at Rotary Intersections

Authors: Antonio Pratelli, Lorenzo Brocchini, Reginald Roy Souleyrette

Abstract:

A rotary is a traffic circle intersection where vehicles entering from branches give priority to circulating flow. Vehicles entering the intersection from converging roads move around the central island and weave out of the circle into their desired exiting branch. This creates merging and diverging conflicts among any entry and its successive exit, i.e., a section. Therefore, rotary capacity models are usually based on the weaving of the different movements in any section of the circle, and the maximum rate of flow value is then related to each weaving section of the rotary. Nevertheless, the single-section capacity value does not lead to the typical performance characteristics of the intersection, such as the entry average delay which is directly linked to its level of service. From another point of view, modern roundabout capacity models are based on the limitation of the flow entering from the single entrance due to the amount of flow circulating in front of the entrance itself. Modern roundabouts capacity models generally lead also to a performance evaluation. This paper aims to incorporate a modern roundabout capacity model into an old rotary capacity method to obtain from the latter the single input capacity and ultimately achieve the related performance indicators. Put simply; the main objective is to calculate the average delay of each single roundabout entrance to apply the most common Highway Capacity Manual, or HCM, criteria. The paper is organized as follows: firstly, the rotary and roundabout capacity models are sketched, and it has made a brief introduction to the model combination technique with some practical instances. The successive section is deserved to summarize the TRRL old rotary capacity model and the most recent HCM-7th modern roundabout capacity model. Then, the two models are combined through an iteration-based algorithm, especially set-up and linked to the concept of roundabout total capacity, i.e., the value reached due to a traffic flow pattern leading to the simultaneous congestion of all roundabout entrances. The solution is the average delay for each entrance of the rotary, by which is estimated its respective level of service. In view of further experimental applications, at this research stage, a collection of existing rotary intersections operating with the priority-to-circle rule has already started, both in the US and in Italy. The rotaries have been selected by direct inspection of aerial photos through a map viewer, namely Google Earth. Each instance has been recorded by location, general urban or rural, and its main geometrical patterns. Finally, conclusion remarks are drawn, and a discussion on some further research developments has opened.

Keywords: mixed methods, old rotary and modern roundabout capacity models, total capacity algorithm, level of service estimation

Procedia PDF Downloads 63