Search results for: mean carbon dioxide pressure
1416 Degradation of Commercial Polychlorinated Biphenyl Mixture by Naturally Occurring Facultative Microorganisms via Anaerobic Dechlorination and Aerobic Oxidation
Authors: P. M. G. Pathiraja, P. Egodawatta, A. Goonetilleke, V. S. J. Te'o
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The production and use of Polychlorinated biphenyls (PCBs), a group of synthetic halogenated hydrocarbons have been restricted worldwide due to its toxicity and categorized as one of the twelve priority persistent organic pollutants (POP) by the Stockholm Convention. Low reactivity and high chemical stability of PCBs have made them highly persistent in the environment and bio-concentration and bio-magnification along the food chain contribute to multiple health impacts in humans and animals. Remediating environments contaminated with PCBs is a challenging task for decades. Use of microorganisms for remediation of PCB contaminated soils and sediments have been widely investigated due to the potential of breakdown these complex contaminants with minimum environmental impacts. To achieve an effective bioremediation of polychlorinated biphenyls (PCBs) contaminated environments, microbes were sourced from environmental samples and tested for their ability to hydrolyze PCBs under different conditions. Comparison of PCB degradation efficiencies of four naturally occurring facultative bacterial cultures isolated through selective enrichment under aerobic and anaerobic conditions were simultaneously investigated in minimal salt medium using 50 mg/L Aroclor 1260, a commonly used commercial PCB mixture as the sole source of carbon. The results of a six-week study demonstrated that all the tested facultative Achromobacter, Ochrobactrum, Lysinibacillus and Pseudomonas strains are capable of degrading PCBs under both anaerobic and aerobic conditions while assisting hydrophobic PCBs to make solubilize in the aqueous minimal medium. Overall, the results suggest that some facultative bacteria are capable of effective in degrading PCBs under anaerobic conditions through reductive dechlorination and under aerobic conditions through oxidation. Therefore, use of suitable facultative microorganisms under combined anaerobic-aerobic conditions and combination of such strains capable of solubilization and breakdown of PCBs has high potential in achieving higher PCB removal rates.Keywords: bioremediation, combined anaerobic-aerobic degradation, facultative microorganisms, polychlorinated biphenyls
Procedia PDF Downloads 2411415 Method Development for the Determination of Gamma-Aminobutyric Acid in Rice Products by Lc-Ms-Ms
Authors: Cher Rong Matthew Kong, Edmund Tian, Seng Poon Ong, Chee Sian Gan
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Gamma-aminobutyric acid (GABA) is a non-protein amino acid that is a functional constituent of certain rice varieties. When consumed, it decreases blood pressure and reduces the risk of hypertension-related diseases. This has led to more research dedicated towards the development of functional food products (e.g. germinated brown rice) with enhanced GABA content, and the development of these functional food products has led to increased demand for instrument-based methods that can efficiently and effectively determine GABA content. Current analytical methods require analyte derivatisation, and have significant disadvantages such as being labour intensive and time-consuming, and being subject to analyte loss due to the increased complexity of the sample preparation process. To address this, an LC-MS-MS method for the determination of GABA in rice products has been developed and validated. This developed method involves a relatively simple sample preparation process before analysis using HILIC LC-MS-MS. This method eliminates the need for derivatisation, thereby significantly reducing the labour and time associated with such an analysis. Using LC-MS-MS also allows for better differentiation of GABA from any potential co-eluting compounds in the sample matrix. Results obtained from the developed method demonstrated high linearity, accuracy, and precision for the determination of GABA (1ng/L to 8ng/L) in a variety of brown rice products. The method can significantly simplify sample preparation steps, improve the accuracy of quantitation, and increase the throughput of analyses, thereby providing a quick but effective alternative to established instrumental analysis methods for GABA in rice.Keywords: functional food, gamma-aminobutyric acid, germinated brown rice, method development
Procedia PDF Downloads 2681414 Study of Efficiency of Flying Animal Using Computational Simulation
Authors: Ratih Julistina, M. Agoes Moelyadi
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Innovation in aviation technology evolved rapidly by time to time for acquiring the most favorable value of utilization and is usually denoted by efficiency parameter. Nature always become part of inspiration, and for this sector, many researchers focused on studying the behavior of flying animal to comprehend the fundamental, one of them is birds. Experimental testing has already conducted by several researches to seek and calculate the efficiency by putting the object in wind tunnel. Hence, computational simulation is needed to conform the result and give more visualization which is based on Reynold Averaged Navier-Stokes equation solution for unsteady case in time-dependent viscous flow. By creating model from simplification of the real bird as a rigid body, those are Hawk which has low aspect ratio and Swift with high aspect ratio, subsequently generating the multi grid structured mesh to capture and calculate the aerodynamic behavior and characteristics. Mimicking the motion of downstroke and upstroke of bird flight which produced both lift and thrust, the sinusoidal function is used. Simulation is carried out for varied of flapping frequencies within upper and lower range of actual each bird’s frequency which are 1 Hz, 2.87 Hz, 5 Hz for Hawk and 5 Hz, 8.9 Hz, 13 Hz for Swift to investigate the dependency of frequency effecting the efficiency of aerodynamic characteristics production. Also, by comparing the result in different condition flights with the morphology of each bird. Simulation has shown that higher flapping frequency is used then greater aerodynamic coefficient is obtained, on other hand, efficiency on thrust production is not the same. The result is analyzed from velocity and pressure contours, mesh movement as to see the behavior.Keywords: characteristics of aerodynamic, efficiency, flapping frequency, flapping wing, unsteady simulation
Procedia PDF Downloads 2451413 Finite Element Model to Investigate the Dynamic Behavior of Ring-Stiffened Conical Shell Fully and Partially Filled with Fluid
Authors: Mohammadamin Esmaeilzadehazimi, Morteza Shayan Arani, Mohammad Toorani, Aouni Lakis
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This study uses a hybrid finite element method to predict the dynamic behavior of both fully and partially-filled truncated conical shells stiffened with ring stiffeners. The method combines classical shell theory and the finite element method, and employs displacement functions derived from exact solutions of Sanders' shell equilibrium equations for conical shells. The shell-fluid interface is analyzed by utilizing the velocity potential, Bernoulli's equation, and impermeability conditions to determine an explicit expression for fluid pressure. The equations of motion presented in this study apply to both conical and cylindrical shells. This study presents the first comparison of the method applied to ring-stiffened shells with other numerical and experimental findings. Vibration frequencies for conical shells with various boundary conditions and geometries in a vacuum and filled with water are compared with experimental and numerical investigations, achieving good agreement. The study thoroughly investigates the influence of geometric parameters, stiffener quantity, semi-vertex cone angle, level of water filled in the cone, and applied boundary conditions on the natural frequency of fluid-loaded ring-stiffened conical shells, and draws some useful conclusions. The primary advantage of the current method is its use of a minimal number of finite elements while achieving highly accurate results.Keywords: finite element method, fluid–structure interaction, conical shell, natural frequency, ring-stiffener
Procedia PDF Downloads 781412 3D Numerical Study of Tsunami Loading and Inundation in a Model Urban Area
Authors: A. Bahmanpour, I. Eames, C. Klettner, A. Dimakopoulos
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We develop a new set of diagnostic tools to analyze inundation into a model district using three-dimensional CFD simulations, with a view to generating a database against which to test simpler models. A three-dimensional model of Oregon city with different-sized groups of building next to the coastline is used to run calculations of the movement of a long period wave on the shore. The initial and boundary conditions of the off-shore water are set using a nonlinear inverse method based on Eulerian spatial information matching experimental Eulerian time series measurements of water height. The water movement is followed in time, and this enables the pressure distribution on every surface of each building to be followed in a temporal manner. The three-dimensional numerical data set is validated against published experimental work. In the first instance, we use the dataset as a basis to understand the success of reduced models - including 2D shallow water model and reduced 1D models - to predict water heights, flow velocity and forces. This is because models based on the shallow water equations are known to underestimate drag forces after the initial surge of water. The second component is to identify critical flow features, such as hydraulic jumps and choked states, which are flow regions where dissipation occurs and drag forces are large. Finally, we describe how future tsunami inundation models should be modified to account for the complex effects of buildings through drag and blocking.Financial support from UCL and HR Wallingford is greatly appreciated. The authors would like to thank Professor Daniel Cox and Dr. Hyoungsu Park for providing the data on the Seaside Oregon experiment.Keywords: computational fluid dynamics, extreme events, loading, tsunami
Procedia PDF Downloads 1151411 A Case Study of Brownfield Revitalization in Taiwan
Authors: Jen Wang, Wei-Chia Hsu, Zih-Sin Wang, Ching-Ping Chu, Bo-Shiou Guo
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In the late 19th century, the Jinguashi ore deposit in northern Taiwan was discovered, and accompanied with flourishing mining activities. However, tons of contaminants including heavy metals, sulfur dioxide, and total petroleum hydrocarbons (TPH) were released to surroundings and caused environmental problems. Site T was one of copper smelter located on the coastal hill near Jinguashi ore deposit. In over ten years of operation, variety contaminants were emitted that it polluted the surrounding soil and groundwater quality. In order to exhaust fumes produced from smelting process, three stacks were built along the hill behind the factory. The sediment inside the stacks contains high concentration of heavy metals such as arsenic, lead, copper, etc. Moreover, soil around the discarded stacks suffered a serious contamination when deposition leached from the ruptures of stacks. Consequently, Site T (including the factory and its surroundings) was declared as a pollution remediation site that visiting the site and land-use activities on it are forbidden. However, the natural landscape and cultural attractions of Site T are spectacular that it attracts a lot of visitors annually. Moreover, land resources are extremely precious in Taiwan. In addition, Taiwan Environmental Protection Administration (EPA) is actively promoting the contaminated land revitalization policy. Therefore, this study took Site T as case study for brownfield revitalization planning to the limits of activate and remediate the natural resources. Land-use suitability analysis and risk mapping were applied in this study to make appropriate risk management measures and redevelopment plan for the site. In land-use suitability analysis, surrounding factors into consideration such as environmentally sensitive areas, biological resources, land use, contamination, culture, and landscapes were collected to assess the development of each area; health risk mapping was introduced to show the image of risk assessments results based on the site contamination investigation. According to land-use suitability analysis, the site was divided into four zones: priority area (for high-efficiency development), secondary area (for co-development with priority area), conditional area (for reusing existing building) and limited area (for Eco-tourism and education). According to the investigation, polychlorinated biphenyls (PCB), heavy metals and TPH were considered as target contaminants while oral, inhalation and dermal would be the major exposure pathways in health risk assessment. In accordance with health risk map, the highest risk was found in the southwest and eastern side. Based on the results, the development plan focused on zoning and land use. Site T was recommended be divides to public facility zone, public architectonic art zone, viewing zone, existing building preservation zone, historic building zone, and cultural landscape zone for various purpose. In addition, risk management measures including sustained remediation, extinguish exposure and administration management are applied to ensure particular places are suitable for visiting and protect the visitors’ health. The consolidated results are corroborated available by analyzing aspects of law, land acquired method, maintenance and management and public participation. Therefore, this study has a certain reference value to promote the contaminated land revitalization policy in Taiwan.Keywords: brownfield revitalization, land-use suitability analysis, health risk map, risk management
Procedia PDF Downloads 1841410 Parametric Optimization of High-Performance Electric Vehicle E-Gear Drive for Radiated Noise Using 1-D System Simulation
Authors: Sanjai Sureshkumar, Sathish G. Kumar, P. V. V. Sathyanarayana
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For e-gear drivetrain, the transmission error and the resulting variation in mesh stiffness is one of the main source of excitation in High performance Electric Vehicle. These vibrations are transferred through the shaft to the bearings and then to the e-Gear drive housing eventually radiating noise. A parametrical model developed in 1-D system simulation by optimizing the micro and macro geometry along with bearing properties and oil filtration to achieve least transmission error and high contact ratio. Histogram analysis is performed to condense the actual road load data into condensed duty cycle to find the bearing forces. The structural vibration generated by these forces will be simulated in a nonlinear solver obtaining the normal surface velocity of the housing and the results will be carried forward to Acoustic software wherein a virtual environment of the surrounding (actual testing scenario) with accurate microphone position will be maintained to predict the sound pressure level of radiated noise and directivity plot of the e-Gear Drive. Order analysis will be carried out to find the root cause of the vibration and whine noise. Broadband spectrum will be checked to find the rattle noise source. Further, with the available results, the design will be optimized, and the next loop of simulation will be performed to build a best e-Gear Drive on NVH aspect. Structural analysis will be also carried out to check the robustness of the e-Gear Drive.Keywords: 1-D system simulation, contact ratio, e-Gear, mesh stiffness, micro and macro geometry, transmission error, radiated noise, NVH
Procedia PDF Downloads 1491409 Evaluating the Impact of Future Scenarios on Water Availability and Demand Based on Stakeholders Prioritized Water Management Options in the Upper Awash Basin, Ethiopia
Authors: Adey Nigatu Mersha, Ilyas Masih, Charlotte de Fraiture, Tena Alamirew
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Conflicts over water are increasing mainly as a result of water scarcity in response to higher water demand and climatic variability. There is often not enough water to meet all demands for different uses. Thus, decisions have to be made as to how the available resources can be managed and utilized. Correspondingly water allocation goals, practically national water policy goals, need to be revised accordingly as the pressure on water increases from time to time. A case study is conducted in the Upper Awash Basin, Ethiopia, to assess and evaluate prioritized comprehensive water demand management options based on the framework of integrated water resources management in account of stakeholders’ knowledge and preferences as well as practical prominence within the Upper Awash Basin. Two categories of alternative management options based on policy analysis and stakeholders' consultation were evaluated against the business-as-usual scenario by using WEAP21 model as an analytical tool. Strong effects on future (unmet) demands are observed with major socio-economic assumptions and forthcoming water development plans. Water management within the basin will get more complex with further abstraction which may lead to an irreversible damage to the ecosystem. It is further confirmed through this particular study that efforts to maintain users’ preferences alone cannot insure economically viable and environmentally sound development and vice versa. There is always a tradeoff between these factors. Hence, all of these facets must be analyzed separately, related with each other in equal footing, and ultimately taken up in decision making in order for the whole system to function properly.Keywords: water demand, water availability, WEAP21, scenarios
Procedia PDF Downloads 2801408 Predictive Factors of Healthcare-Associated Infections and Antibiotic Use Patterns: A Cross-Sectional Survey at the Charles Nicolle Hospital of Tunis
Authors: Nouira Mariem, Ennigrou Samir
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Background and aims: Healthcare-associated infections (HAI) represent a major public health problem worldwide. They represent one of the most serious adverse events in health care. The objectives of our study were to estimate the prevalence of HAI at the Charles Nicolle Hospital (CNH) and to identify the main associated factors as well as to estimate the frequency of antibiotic use. Methods: It was a cross-sectional study at the CNH with a unique passage per department (October-December 2018). All patients present at the wards for more than 48 hours were included. All patients from outpatient consultations, emergency, and dialysis departments were not included. The site definitions of infections proposed by the Centers for Disease Control and Prevention (CDC) were used. Only clinically and/or microbiologically confirmed active HAIs were included. Results: A total of 318 patients were included, with a mean age of 52 years and a sex ratio (female/male) of 1.05. A total of 41 patients had one or more active HAIs, corresponding to a prevalence of 13.1% (95% CI: 9.3%-16.9%). The most frequent site infections were urinary tract infections and pneumonia. Multivariate analysis among adult patients (>=18 years) (n=261) revealed that infection on admission (p=0.01), alcoholism (p=0.01), high blood pressure (p=0.008), having at least one invasive device inserted (p=0.004), and history of recent surgery (p=0.03), increased the risk of HAIs significantly. More than 1 of 3 patients (35.4%) were under antibiotics on the day of the survey, of which more than half (57.4%) were under two or more types of antibiotics. Conclusion: The prevalence of HAIs and antibiotic prescriptions at the CNH were considerably high. An infection prevention and control committee, as well as the development of an antibiotic stewardship program with continuous monitoring using repeated prevalence surveys, must be implemented to limit the frequency of these infections effectively.Keywords: prevalence, healthcare associated infection, antibiotic, Tunisia
Procedia PDF Downloads 821407 Opioid Administration on Patients Hospitalized in the Emergency Department
Authors: Mani Mofidi, Neda Valizadeh, Ali Hashemaghaee, Mona Hashemaghaee, Soudabeh Shafiee Ardestani
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Background: Acute pain and its management remained the most complaint of emergency service admission. Diagnostic and therapeutic procedures add to patients’ pain. Diminishing the pain increases the quality of patient’s feeling and improves the patient-physician relationship. Aim: The aim of this study was to evaluate the outcomes and side effects of opioid administration in emergency patients. Material and Methods: patients admitted to ward II emergency service of Imam Khomeini hospital, who received one of the opioids: morphine, pethidine, methadone or fentanyl as an analgesic were evaluated. Their vital signs and general condition were examined before and after drug injection. Also, patient’s pain experience were recorded as numerical rating score (NRS) before and after analgesic administration. Results: 268 patients were studied. 34 patients were addicted to opioid drugs. Morphine had the highest rate of prescription (86.2%), followed by pethidine (8.5%), methadone (3.3%) and fentanyl (1.68). While initial NRS did not show significant difference between addicted patients and non-addicted ones, NRS decline and its score after drug injection were significantly lower in addicted patients. All patients had slight but statistically significant lower respiratory rate, heart rate, blood pressure and O2 saturation. There was no significant difference between different kind of opioid prescription and its outcomes or side effects. Conclusion: Pain management should be always in physicians’ mind during emergency admissions. It should not be assumed that an addicted patient complaining of pain is malingering to receive drug. Titration of drug and close monitoring must be in the curriculum to prevent any hazardous side effects.Keywords: numerical rating score, opioid, pain, emergency department
Procedia PDF Downloads 4261406 The Numerical and Experimental Analysis of Compressed Composite Plate in Asymmetrical Arrangement of Layers
Authors: Katarzyna Falkowicz
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The work focused on the original concept of a thin-walled plate element with a cut-out, for use as a spring or load-bearing element. The subject of the study were rectangular plates with a cut-out with variable geometrical parameters and with a variable angle of fiber arrangement, made of a carbon-epoxy composite with high strength properties in an asymmetrical arrangement, subjected to uniform compression. The influence of geometrical parameters of the cut-out and the angle of fiber arrangement on the value of critical load of the structure and buckling form was investigated. Uniform thin plates are relatively cheap to manufacture, however due to their low bending stiffness; they can carry relatively small loads. The lowest form of loss of plate stability, which is the bending form, leads to its rapid destruction due to high deflection increases, with a slight increase in compressive load - low rigidity of the structure. However, the stiffness characteristics of the structure change significantly when the work of plate is forcing according to the higher flexural-torsional form of buckling. The plate is able to carry a much higher compressive load while maintaining much stiffer work characteristics in the post-critical range. The calculations carried out earlier show that plates with forced higher form of buckling are characterized by stable, progressive paths of post-critical equilibrium, enabling their use as elastic elements. The characteristics of such elements can be designed in a wide range by changing the geometrical parameters of the cut-out, i.e. height and width as well as by changing the angle of fiber arrangement The commercial ABAQUS program using the finite element method was used to develop the discrete model and perform numerical calculations. The obtained results are of significant practical importance in the design of structures with elastic elements, allowing to achieve the required maintenance characteristics of the device.Keywords: buckling mode, numerical method, unsymmetrical laminates, thin-walled elastic elements
Procedia PDF Downloads 1051405 Understanding Algerian International Student Mental Health Experiences in UK (United Kingdom) Universities: Difficulties of Disclosure, Help-Seeking and Coping Strategies
Authors: Nesrine Boussaoui
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Background: International students often encounter challenges while studying in the UK, including communication and language barriers, lack of social networks, and socio-cultural differences that adversely impact on their mental health. For Algerian international students (AISs), these challenges may be heightened as English is not their first language and the culture of their homeland is substantially different from British culture, yet research has to incorporate their experiences and perspectives. Aim: The current study aimed to explore AISs’ 1) understandings of mental health; 2) issues of disclosure for mental health difficulties; and 3) mental health help-seeking and coping strategies. Method: In-depth, audio recorded semi-structured interviews (n = 20) with AISs in UK universities were conducted. An inductive, reflective thematic approach analysis was used. Finding: The following themes and associated sub-themes were developed: (1) Algerian cultural influences on mental health understanding(socio-cultural comparisons); (2) the paradox of the family (pressure vs. support); (3) stigma and fear of disclosure; (4) Barriers to formal help-seeking (informal disclosure as first step to seeking help); (5) Communication barriers (resort to mother tongue to disclose); (6) Self-reliance and religious coping. Conclusion: Recognising and understanding the challenges faced by AISs in terms of disclosure and mental health help-seeking is essential to reduce barriers to formal help-seeking. Informal disclosure among peers is often the first step to seeking help. Enhancing practitioners’ cultural competences and awareness of diverse understandings of mental health and the role of religious coping among AISs’ may have transferable benefits to a wider international student population.Keywords: mental health, stegma, coping, disclosure
Procedia PDF Downloads 1421404 Improvement Performances of the Supersonic Nozzles at High Temperature Type Minimum Length Nozzle
Authors: W. Hamaidia, T. Zebbiche
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This paper presents the design of axisymmetric supersonic nozzles, in order to accelerate a supersonic flow to the desired Mach number and that having a small weight, in the same time gives a high thrust. The concerned nozzle gives a parallel and uniform flow at the exit section. The nozzle is divided into subsonic and supersonic regions. The supersonic portion is independent to the upstream conditions of the sonic line. The subsonic portion is used to give a sonic flow at the throat. In this case, nozzle gives a uniform and parallel flow at the exit section. It’s named by minimum length Nozzle. The study is done at high temperature, lower than the dissociation threshold of the molecules, in order to improve the aerodynamic performances. Our aim consists of improving the performances both by the increase of exit Mach number and the thrust coefficient and by reduction of the nozzle's mass. The variation of the specific heats with the temperature is considered. The design is made by the Method of Characteristics. The finite differences method with predictor-corrector algorithm is used to make the numerical resolution of the obtained nonlinear algebraic equations. The application is for air. All the obtained results depend on three parameters which are exit Mach number, the stagnation temperature, the chosen mesh in characteristics. A numerical simulation of nozzle through Computational Fluid Dynamics-FASTRAN was done to determine and to confirm the necessary design parameters.Keywords: flux supersonic flow, axisymmetric minimum length nozzle, high temperature, method of characteristics, calorically imperfect gas, finite difference method, trust coefficient, mass of the nozzle, specific heat at constant pressure, air, error
Procedia PDF Downloads 1501403 Role of Green Ecology in Business Development
Authors: Ashfaq Ahmed Kharal
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The study asserts that environment-friendly practices are increasingly being used by businesses throughout the world. Today, there is a great deal of interest in green management from both practitioners and academics. People expect managers to use resources intelligently and responsibly and to minimize the use of water, minerals, and other components in the finished products, as a crucial factor in this passion. The ethical or moral relevance of green management cannot be overstated. Employee Green Behavior (EGB) and environmental sustainability were shown to be significantly influenced by green human resource management (GHRM) in this study. Environmental issues, such as climate change, global warming, and resource conservation have a direct impact on business activities. The environment, society, and economy all suffer as a result of such obstacles. The depletion of natural resources needs immediate replenishment. As a result of government, non-governmental organizations (NGOs), environmental activists, and labor unions putting pressure on businesses and firms are now required to operate in ecologically responsible ways. Organizations are increasingly concerned about environmental sustainability in light of contemporary environmental circumstances and commercial marketplaces. Companies that emphasize long-term viability will benefit from integrating green employee behavior, green human resource management techniques, and environmental sustainability. Competition drives firms to respond to external causes, adapt, and evolve in response to changing conditions in the marketplace. Organizations develop strategic capabilities to transform their resources and acquire a competitive edge while implementing a business plan. The study of GHRM's function is being prioritized since environmental sustainability is becoming a more important strategic goal.Keywords: EGB, GHRM, environment sustainability, green ecology
Procedia PDF Downloads 1051402 The Shrinking Nature of Parliamentary Immunity in Kenya: A Proposal for Judicial Restraint
Authors: Oscar Sang, Shadrack David Rotich
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Parliamentary immunity is grounded on the notion that parliaments need certain rights or immunities to ensure they can operate independently make fair and impartial decisions without capitulating to political pressure or intimidation. The 2013 election in Kenya marked an important milestone in the development of the law of parliamentary privilege. Such importance relates to the dramatic increase in the number of legislatures in the country from one unicameral parliament, to a bicameral national parliament and forty-seven other regional legislative assemblies. The increase in legislatures has resulted in a dramatic increase in political contestations which have led to legal wrangles. The judiciary in Kenya, once considered submissive, has been invited to arbitrate on various matters pitting individual rights and parliamentary privilege and have invalidated a number of legislative action. While judicial intervention is indeed necessary to ensure that legislatures in Kenya live true to the constitutional aspirations of the Kenyan people, certain judicial decisions have had an effect on eroding parliamentary immunity. This paper highlights a number of instances in which it could be argued that parliamentary privilege came under attack by the courts in Kenya. The paper aims to make a case that while Kenya’s progressive constitution necessitates the scope and extent of legislature’s immunities and privilege to be determined by the courts, it is important that courts exercise restraint in its review of legislative action. The paper makes the argument that unrestrained judicial action in Kenya on questions within the realm parliamentary privilege may undermine the functioning of Kenya’s legislatures. The paper explores approaches taken by a number of jurisdictions in establishing a proper balance between maintaining a viable parliamentary privilege regime in a rights-based constitutional system.Keywords: Kenya, constitution, judicial restraint, parliamentary privilege
Procedia PDF Downloads 1691401 Psychiatric Risk Assessment in the Emergency Department: The Impact of NEAT on the Management of Mental Health Patients
Authors: Euan Donley
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Emergency Departments (EDs) are heavily burdened as presentation rates continue to rise. To improve patient flow National Emergency Access Targets (NEAT) were introduced. NEAT implements timelines for ED presentations, such as discharging patients within four hours of arrival. Mental health patients use EDs more than the general population and are generally more complex in their presentations. The aim of this study is to examine the impact of NEAT on psychiatric risk assessment of mental health patients in the ED. Seventy-eight mental health clinicians from 7 Victoria, Australia, hospital EDs participated in a mixed method analysis via anonymous online survey. NEAT was considered helpful as mental health patients were seen quicker, were less likely to abscond, could improve teamwork amongst ED staff, and in some cases administrative processes were better streamlined. However, clinicians felt that NEAT was also responsible for less time with patients and relatives’, resulted in rushed assessments, placed undue pressure on mental health clinicians, was not conducive to training, and the emphasis on time was the wrong focus for patient treatment. The profile of a patient typically likely to be treated within NEAT timelines showed a perfect storm of luck and compliance. If a patient was sober, medically stable, referred early, did not require much collateral information and did not have distressed relatives, NEAT was more likely to be met. Organisationally participants reported no organisational change or training to meet NEAT. Poor mental health staffing, multiple ED presentations and a shortage of mental health beds also hamper meeting NEAT. Findings suggest participants were supportive of NEAT in principle, but a demanding workload and organisational barriers meant NEAT had an overall negative effect on psychiatric risk assessment of mental health patients in ED.Keywords: assessment, emergency, risk, psychiatric
Procedia PDF Downloads 5161400 Synthesis of Magnetic Plastic Waste-Reduced Graphene Oxide Composite and Its Application in Dye Adsorption from Aqueous Solution
Authors: Pamphile Ndagijimana, Xuejiao Liu, Zhiwei Li, Yin Wang
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The valorization of plastic wastes, as a mitigation strategy, is attracting the researchers’ attention since these wastes have raised serious environmental concerns. Plastic wastes have been reported to adsorb the organic pollutants in the water environment and to be the main vector of those pollutants in the aquatic environment, especially dyes, as a serious water pollution concern. Recycling technologies of plastic wastes such as landfills, incineration, and energy recovery have been adopted to manage those wastes before getting exposed to the environment. However, they are far from being widely accepted due to their related environmental pollution, lack of space for the landfill as well as high cost. Therefore, modification is necessary for green plastic adsorbent in water applications. Current routes for plastic modification into adsorbents are based on the combustion method, but they have weaknesses of air pollution as well as high cost. Thus, the green strategy for plastic modification into adsorbents is highly required. Furthermore, recent researchers recommended that if plastic wastes are combined with other solid carbon materials, they could promote their application in water treatment. Herein, we present new insight into using plastic waste-based materials as future green adsorbents. Magnetic plastic-reduced graphene oxide (MPrGO) composite was synthesized by cross-linking method and applied in removing methylene blue (MB) from an aqueous solution. Furthermore, the following advantages have been achieved: (i) The density of plastic and reduced graphene oxide were enhanced, (ii) no second pollution of black color in solution, (iii) small amount of graphene oxide (1%) was linked on 10g of plastic waste, and the composite presented the high removal efficiency, (iv) easy recovery of adsorbent from water. The low concentration of MB (10-30mg/L) was all removed by 0.3g of MPrGO. Different characterization techniques such as XRD, SEM, FTIR, BET, XPS, and Raman spectroscopy were performed, and the results confirmed a conjugation between plastic waste and graphene oxide. This MPrGO composite presented a good prospect for the valorization of plastic waste, and it is a promising composite material in water treatment.Keywords: plastic waste, graphene oxide, dye, adsorption
Procedia PDF Downloads 891399 Unveiling the Potential of Hydroponics as a Climate-Smart Technology for Small-Scale Farming and Food Security in Africa
Authors: Margaret S. Gumisiriza, Ernest. R. Mbega, Patrick Ndakidemi, Businge K. Edward
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The purpose of the paper was to assess existing literature regarding hydroponics in both the developing and developed countries. Furthermore, relate it to the context of African countries, how they can implement it and benefit from it in the face of climate change, high population growth rates, and reduced food production. Agriculture remains the major economic activity for a number of African countries. It is the source of income for most peasants, and still contributes to the Gross Domestic Product in most of these African countries. Unfortunately, climate change coupled with the increasing rates of population growth; rural-urban migration; and urbanization have led to food insecurity due to a reduction of available land for agriculture. This has further intensified the food security dilemma in Africa, especially in urban areas, where land is already limited. Considering the aforementioned state of affairs, there is an increasing demand for interventions that can help farmers in Africa to cope with climate change and increase food production. This review explores hydroponic farming and how it can be used as a climate-smart farming system in Africa’s rural and urban areas. Specifically, the review focuses on hydroponics, requirements for hydroponic farming and the state of hydroponic farming in LDCs and Developed countries (DCs). From the review, it was observed that African countries especially those that receive a lot of sunlight would highly benefit from the solar-powered hydroponic farming systems. Further, still, this farming system will help African countries cope with the challenges of high population pressure in urban areas and climate change as it qualifies to be an urban farming system.Keywords: Africa, climate-smart agriculture, solar-powered-hydroponics, urban-farming
Procedia PDF Downloads 2751398 The Factors Associated with Health Status among Community Health Volunteers in Thailand
Authors: Lapatrada Numkham, Saowaluk Khakhong, Jeeraporn Kummabutr
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Non-communicable diseases (NCDs) are the leading cause of death in worldwide. Thailand also concerns and focuses on reduction a new case of these diseases. Community Health Volunteers (CHV) is important health personnel in primary health care and performs as a health leader in the community. If the health of CHV changes, it would impact on the performance to promote health of families and community. This cross-sectional study aimed to 1) describe the health status of community health volunteers and 2) examine the factors associated with health status among community health volunteers. The sample included 360 community health volunteers in a province in central Thailand during September-December 2014. Data were collected using questionnaires on health information, knowledge of health behaviors, and health behaviors. Body weight, height, waist circumference (WC), blood pressure (BP), and blood glucose (BS) (fingertip) were assessed. Data were analyzed using descriptive statistics and chi-square test. There were three hundred and sixty participants with 82.5% being women. The mean age was 54 + 8.9 years. Forty-seven percent of the participants had co-morbidities. Hypertension was the most common co-morbidity (26.7%). The results revealed that the health status of the volunteers included: no underlying disease, having risk of hypertension (HT) & diabetes mellitus (DM), and having HT&DM at 38.3%, 30.0%, and 31.7% respectively. The chi-square test revealed that the factors associated with health status among the volunteers were gender, age, WC and body mass index (BMI). The results suggested that community health nurses should; 1) implement interventions to decrease waist circumference and lose weight through education programs, especially females; 2) monitor people that have a risk of HT&DM and that have HT&DM by meeting and recording BP level, BS level, WC and BMI; and 3) collaborate with a district public health officer to initiate a campaign to raise awareness of the risks of chronic diseases among community health volunteers.Keywords: community health volunteers, health status, risk of non-communicable disease, Thailand
Procedia PDF Downloads 3581397 Quantitative Evaluation on Community Perceptions of Sanitation and Hygiene in Rural Guatemala
Authors: Akudo Ejelonu, Sarah Willig, J. Anthony Sauder, Heather Murphy, Frances Shofer
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Background: The high prevalence of diarrheal diseases in the village of Tzununá, Guatemala is linked to lack of sanitation facilities and handwashing practices. Diarrheal diseases are preventable and improved access to latrines, hygiene education and clean water may improve sanitation by reducing the spread of disease. Objective: Between May 2015-January 2017, the University of Pennsylvania Chapter of Engineers Without Border (PennEWB) and local partners designed an intervention to reduce diarrheal disease by building pour flush latrines in 50 individual households and providing education on the importance of handwashing practice. Design/Methods: Through convenient sampling, we surveyed 45 households to evaluate the community’s knowledge of diarrheal disease, handwashing practices, and maintenance of the latrines. Results: 92% of the study participants experienced decrease of new cases of diarrheal disease after receiving a latrine. Only 11% washed their hands after defecating in the latrine. There was gap in understanding the health outcome of latrine sanitation and handwashing education. The respondents did not connect the reduction of diarrheal disease with latrine use and maintenance. Instead, they associated their motivation for latrine use with aesthetics, proximity to their home, ease and comfort, and reduction of shame. We recommend that PennEWB adopt UNICEF or WHO education on hand washing practice. Conclusion: Social interaction and social pressure drove the household use of latrines. The latrines are being valued and cleaned. The education that the residents received did not target norms and behaviors. Latrines could be used to create a new social norm that supports behavioral change.Keywords: diarrheal disease, latrine, open defecation, water, sanitation and hygiene
Procedia PDF Downloads 1571396 Scope, Relevance and Sustainability of Decentralized Renewable Energy Systems in Developing Economies: Imperatives from Indian Case Studies
Authors: Harshit Vallecha, Prabha Bhola
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‘Energy for all’, is a global issue of concern for the past many years. Despite the number of technological advancements and innovations, significant numbers of people are living without access to electricity around the world. India, an emerging economy, tops the list of nations having the maximum number of residents living off the grid, thus raising global attention in past few years to provide clean and sustainable energy access solutions to all of its residents. It is evident from developed economies that centralized planning and electrification alone is not sufficient for meeting energy security. Implementation of off-grid and consumer-driven energy models like Decentralized Renewable Energy (DRE) systems have played a significant role in meeting the national energy demand in developed nations. Cases of DRE systems have been reported in developing countries like India for the past few years. This paper attempts to profile the status of DRE projects in the Indian context with their scope and relevance to ensure universal electrification. Diversified cases of DRE projects, particularly solar, biomass and micro hydro are identified in different Indian states. Critical factors affecting the sustainability of DRE projects are extracted with their interlinkages in the context of developers, beneficiaries and promoters involved in such projects. Socio-techno-economic indicators are identified through similar cases in the context of DRE projects. Exploratory factor analysis is performed to evaluate the critical sustainability factors followed by regression analysis to establish the relationship between the dependent and independent factors. The generated EFA-Regression model provides a basis to develop the sustainability and replicability framework for broader coverage of DRE projects in developing nations in order to attain the goal of universal electrification with least carbon emissions.Keywords: climate change, decentralized generation, electricity access, renewable energy
Procedia PDF Downloads 1241395 Transformer Life Enhancement Using Dynamic Switching of Second Harmonic Feature in IEDs
Authors: K. N. Dinesh Babu, P. K. Gargava
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Energization of a transformer results in sudden flow of current which is an effect of core magnetization. This current will be dominated by the presence of second harmonic, which in turn is used to segregate fault and inrush current, thus guaranteeing proper operation of the relay. This additional security in the relay sometimes obstructs or delays differential protection in a specific scenario, when the 2nd harmonic content was present during a genuine fault. This kind of scenario can result in isolation of the transformer by Buchholz and pressure release valve (PRV) protection, which is acted when fault creates more damage in transformer. Such delays involve a huge impact on the insulation failure, and chances of repairing or rectifying fault of problem at site become very dismal. Sometimes this delay can cause fire in the transformer, and this situation becomes havoc for a sub-station. Such occurrences have been observed in field also when differential relay operation was delayed by 10-15 ms by second harmonic blocking in some specific conditions. These incidences have led to the need for an alternative solution to eradicate such unwarranted delay in operation in future. Modern numerical relay, called as intelligent electronic device (IED), is embedded with advanced protection features which permit higher flexibility and better provisions for tuning of protection logic and settings. Such flexibility in transformer protection IEDs, enables incorporation of alternative methods such as dynamic switching of second harmonic feature for blocking the differential protection with additional security. The analysis and precautionary measures carried out in this case, have been simulated and discussed in this paper to ensure that similar solutions can be adopted to inhibit analogous issues in future.Keywords: differential protection, intelligent electronic device (IED), 2nd harmonic inhibit, inrush inhibit
Procedia PDF Downloads 2991394 Phase Changing Dicationic Polymeric Ionic Liquid with CO2 Capture Abilities
Authors: Swati Sundararajan, Asit B. Samui, Prashant S. Kulkarni
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Polymeric ionic liquids combine the properties of ionic liquids and polymers into a single material which has gained massive interest in the recent years. These ionic liquids offer several advantages such as high phase change enthalpy, wide temperature range, chemical and thermal stability, non-volatility and the ability to make them task-specific. Separation of CO2 is an area of critical importance due to the concerns over greenhouse gasses leading to global warming. Thermal energy storage materials, also known as phase change materials absorb latent heat during fusion process and release the absorbed energy to the surrounding environment during crystallization. These materials retain this property over a number of cycles and therefore, are useful for bridging the gap between energy requirement and use. In an effort to develop materials, which will help in minimizing the growing energy demand and environmental concerns, a series of dicationic poly(ethylene glycol) based polymeric ionic liquids were synthesized. One part of an acrylate of poly(ethylene glycol) was reacted with imidazolium quarternizing agent and the second part was reacted with triazolium quarternizing agent. These two different monomers were then copolymerized to prepare dicationic polymeric ionic liquid. These materials were characterized for solid-liquid phase transition and the enthalpy by using differential scanning calorimetry. The CO2 capture studies were performed on a fabricated setup with varying pressure range from 1-20 atm. The findings regarding the prepared materials, having potential dual applications in the fields of thermal energy storage and CO2 capture, will be discussed in the presentation.Keywords: CO2 capture, phase change materials, polyethylene glycol, polymeric ionic liquids, thermal energy storage
Procedia PDF Downloads 2541393 Machine Learning Based Anomaly Detection in Hydraulic Units of Governors in Hydroelectric Power Plants
Authors: Mehmet Akif Bütüner, İlhan Koşalay
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Hydroelectric power plants (HEPPs) are renewable energy power plants with the highest installed power in the world. While the control systems operating in these power plants ensure that the system operates at the desired operating point, it is also responsible for stopping the relevant unit safely in case of any malfunction. While these control systems are expected not to miss signals that require stopping, on the other hand, it is desired not to cause unnecessary stops. In traditional control systems including modern systems with SCADA infrastructure, alarm conditions to create warnings or trip conditions to put relevant unit out of service automatically are usually generated with predefined limits regardless of different operating conditions. This approach results in alarm/trip conditions to be less likely to detect minimal changes which may result in serious malfunction scenarios in near future. With the methods proposed in this research, routine behavior of the oil circulation of hydraulic governor of a HEPP will be modeled with machine learning methods using historical data obtained from SCADA system. Using the created model and recently gathered data from control system, oil pressure of hydraulic accumulators will be estimated. Comparison of this estimation with the measurements made and recorded instantly by the SCADA system will help to foresee failure before becoming worse and determine remaining useful life. By using model outputs, maintenance works will be made more planned, so that undesired stops are prevented, and in case of any malfunction, the system will be stopped or several alarms are triggered before the problem grows.Keywords: hydroelectric, governor, anomaly detection, machine learning, regression
Procedia PDF Downloads 971392 Visual Improvement Outcome of Pars Plana Vitrectomy Combined Endofragmentation and Secondary IOL Implantation for Dropped Nucleus After Cataract Surgery : A Case Report
Authors: Saut Samuel Simamora
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PURPOSE: Nucleus drop is one of the most feared and severe complications of modern cataract surgery. The lens material may drop through iatrogenic breaks of the posterior capsule. The incidence of the nucleus as the complication of phacoemulsification increases concomitant to the increased frequency of phacoemulsification. Pars plana vitrectomy (PPV) followed by endofragmentation and secondary intraocular lens (IOL) implantation is the choice of management procedure. This case report aims to present the outcome of PPV for the treatment dropped nucleus after cataract surgery METHODS: A 65 year old female patient came to Vitreoretina department with chief complaints blurry vision in her left eye after phacoemulsification one month before. Ophthalmological examination revealed visual acuity of the right eye (VA RE) was 6/15, and the left eye (VA LE) was hand movement. The intraocular pressure (IOP) on the right eye was 18 mmHg, and on the left eye was 59 mmHg. On her left eye, there were aphakic, dropped lens nucleus and secondary glaucoma.RESULTS: The patient got antiglaucoma agent until her IOP was decreased. She underwent pars plana vitrectomy to remove dropped nucleus and iris fixated IOL. One week post operative evaluation revealed VA LE was 6/7.5 and iris fixated IOL in proper position. CONCLUSIONS: Nucleus drop generally occurs in phacoemulsification cataract surgery techniques. Retained lens nucleus or fragments in the vitreous may cause severe intraocular inflammation leading to secondary glaucoma. The proper and good management for retained lens fragments in nucleus drop give excellent outcome to patient.Keywords: secondary glaucoma, complication of phacoemulsification, nucleus drop, pars plana vitrectomy
Procedia PDF Downloads 791391 The Relationship of Socioeconomic Status and Levels of Delinquency among Senior High School Students with Secured Attachment to Their Mothers
Authors: Aldrin Avergas, Quennie Mariel Peñaranda, Niña Karen San Miguel, Alexis Katrina Agustin, Peralta Xusha Mae, Maria Luisa Sison
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The research is entitled “The Relationship of Socioeconomic Status and Levels of Delinquency among Senior High School Students with Secured Attachment to their Mothers”. The researchers had explored the relationship between socioeconomic status and delinquent tendencies among grade 11 students. The objective of the research is to discover if delinquent behavior will have a relationship with the current socio-economic status of an adolescent student having a warm relationship with their mothers. The researchers utilized three questionnaires that would measure the three variables of the study, namely: (1) 1SEC 2012: The New Philippines Socioeconomic Classification System was used to show the current socioeconomic status of the respondents, (2) Self-Reported Delinquency – Problem Behavior Frequency Scale was utilized to determine the individual's frequency in engaging to delinquent behavior, and (3) Inventory of Parent and Peer Attachment Revised (IPPA-R) was used to determine the attachment style of the respondents. The researchers utilized a quantitative research design, specifically correlation research. The study concluded that there is no significant relationship between socioeconomic status and academic delinquency despite the fact that these participants had secured attachment to their mother hence this research implies that delinquency is not just a problem for students belonging in the lower socio-economic status and that even having a warm and close relationship with their mothers is not sufficient enough for these students to completely be free from engaging in delinquent acts. There must be other factors (such as peer pressure, emotional quotient, self-esteem or etc.) that are might be contributing to delinquent behaviors.Keywords: adolescents, delinquency, high school students, secured attachment style, socioeconomic status
Procedia PDF Downloads 1861390 Development of Natural Zeolites Adsorbent: Preliminary Study on Water-Isopropyl Alcohol Adsorption in a Close-Loop Continuous Adsorber
Authors: Sang Kompiang Wirawan, Pandu Prabowo Jati, I Wayan Warmada
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Klaten Indonesian natural zeolite can be used as powder or pellet adsorbent. Pellet adsorbent has been made from activated natural zeolite powder by a conventional pressing method. Starch and formaldehyde were added as binder to strengthen the construction of zeolite pellet. To increase the absorptivity and its capacity, natural zeolite was activated first chemically and thermally. This research examined adsorption process of water from Isopropyl Alcohol (IPA)-water system using zeolite adsorbent pellet from natural zeolite powder which has been activated with H2SO4 0.1 M and 0.3 M. Adsorbent was pelleted by pressing apparatus at certain pressure to make specification in 1.96 cm diameter, 0.68 cm thickness which the natural zeolite powder (-80 mesh). The system of isopropyl-alcohol water contained 80% isopropyl-alcohol. Adsorption process was held in close-loop continuous apparatus which the zeolite pellet was put inside a column and the solution of IPA-water was circulated at certain flow. Concentration changing was examined thoroughly at a certain time. This adsorption process included mass transfer from bulk liquid into film layer and from film layer into the solid particle. Analysis of rate constant was using first order isotherm model that simulated with MATLAB. Besides using first order isotherm, intra-particle diffusion model was proposed by using pore diffusion model. The study shows that adsorbent activated by H2SO4 0.1 M has good absorptivity with mass transfer constant at 0.1286 min-1.Keywords: intra-particle diffusion, fractional attainment, first order isotherm, zeolite
Procedia PDF Downloads 3111389 Turbulent Flow Characteristics and Bed Morphology around Circular Bridge Pier
Authors: Pratik Acharya
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Scour is the natural phenomenon brought about by erosive action of the flowing stream in alluvial channels. Frequent scouring around bridge piers may cause damage to the structures. In alluvial channels, a complex interaction between the streamflow and the bed particles results in scouring around piers. Thus, the study of characteristics of flow around piers can give sound knowledge about the scouring process. The present research has been done to investigate the turbulent flow characteristics around bridge piers and corresponding changes in bed morphology. Laboratory experiments were carried out in a tilting flume with a sand bed. The velocities around the pier are measured by Acoustic Doppler Velocimeter. Measurements show that at upstream of the pier velocity and Reynolds stresses are negative near the bed and near the free surface at downstream of the pier. At the downstream of the pier, Reynolds stresses changes rapidly due to the formation of wake vortices. Experimental results show that secondary currents are more predominant at the downstream of the pier. As the flowing stream hits the pier, the flow gets separated in the form of downflow along the face of the pier due to a strong pressure gradient and along the sides of the piers. Separation of flow around the pier leads to scour the bed material and develop the vortex. The downflow hits the bed and removes the bed material, which can be carried forward by the flow circulations along sides of the piers. Eroded bed material is deposited along the centerline at the rear side of the pier and produces hump in the downstream region. Initially, the rate of scouring is high and reduces gradually with increasing time. After a certain limit, equilibrium sets between the erosive capacity of the flowing stream and resistance to the motion by bed particles.Keywords: acoustic doppler velocimeter, pier, Reynolds stress, scour depth, velocity
Procedia PDF Downloads 1481388 Predicting Foreign Direct Investment of IC Design Firms from Taiwan to East and South China Using Lotka-Volterra Model
Authors: Bi-Huei Tsai
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This work explores the inter-region investment behaviors of integrated circuit (IC) design industry from Taiwan to China using the amount of foreign direct investment (FDI). According to the mutual dependence among different IC design industrial locations, Lotka-Volterra model is utilized to explore the FDI interactions between South and East China. Effects of inter-regional collaborations on FDI flows into China are considered. Evolutions of FDIs into South China for IC design industry significantly inspire the subsequent FDIs into East China, while FDIs into East China for Taiwan’s IC design industry significantly hinder the subsequent FDIs into South China. The supply chain along IC industry includes IC design, manufacturing, packing and testing enterprises. I C manufacturing, packaging and testing industries depend on IC design industry to gain advanced business benefits. The FDI amount from Taiwan’s IC design industry into East China is the greatest among the four regions: North, East, Mid-West and South China. The FDI amount from Taiwan’s IC design industry into South China is the second largest. If IC design houses buy more equipment and bring more capitals in South China, those in East China will have pressure to undertake more FDIs into East China to maintain the leading position advantages of the supply chain in East China. On the other hand, as the FDIs in East China rise, the FDIs in South China will successively decline since capitals have concentrated in East China. Prediction of Lotka-Volterra model in FDI trends is accurate because the industrial interactions between the two regions are included. Finally, this work confirms that the FDI flows cannot reach a stable equilibrium point, so the FDI inflows into East and South China will expand in the future.Keywords: Lotka-Volterra model, foreign direct investment, competitive, Equilibrium analysis
Procedia PDF Downloads 3631387 The Richtmyer-Meshkov Instability Impacted by the Interface with Different Components Distribution
Authors: Sheng-Bo Zhang, Huan-Hao Zhang, Zhi-Hua Chen, Chun Zheng
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In this paper, the Richtmyer-Meshkov instability has been studied numerically by using the high-resolution Roe scheme based on the two-dimensional unsteady Euler equation, which was caused by the interaction between shock wave and the helium circular light gas cylinder with different component distributions. The numerical results further discuss the deformation process of the gas cylinder, the wave structure of the flow field and quantitatively analyze the characteristic dimensions (length, height, and central axial width) of the gas cylinder, the volume compression ratio of the cylinder over time. In addition, the flow mechanism of shock-driven interface gas mixing is analyzed from multiple perspectives by combining it with the flow field pressure, velocity, circulation, and gas mixing rate. Then the effects of different initial component distribution conditions on interface instability are investigated. The results show when the diffusion interface transit to the sharp interface, the reflection coefficient gradually increases on both sides of the interface. When the incident shock wave interacts with the cylinder, the transmission of the shock wave will transit from conventional transmission to unconventional transmission. At the same time, the reflected shock wave is gradually strengthened, and the transmitted shock wave is gradually weakened, which leads to an increase in the Richtmyer-Meshkov instability. Moreover, the Atwood number on both sides of the interface also increases as the diffusion interface transit to the sharp interface, which leads to an increase in the Rayleigh-Taylor instability and the Kelvin-Helmholtz instability. Therefore, the increase in instability will lead to an increase the circulation, resulting in an increase in the growth rate of gas mixing rate.Keywords: shock wave, He light cylinder, Richtmyer-Meshkov instability, Gaussian distribution
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