Search results for: bridge stay cables
529 Traditional Practices and Indigenous Knowledge for Sustainable Food Waste Reduction: A Lesson from Africa
Authors: Gabriel Sunday Ayayia
Abstract:
Food waste has reached alarming levels worldwide, contributing to food insecurity, resource depletion, and environmental degradation. While numerous strategies exist to mitigate this issue, the role of traditional practices and indigenous knowledge remains underexplored. There is a need to investigate how these age-old practices can contribute to sustainable food waste reduction, particularly in the African context. This study explores the potential of traditional practices and indigenous knowledge in Africa to address this challenge sustainably. The study examines traditional African food management practices and indigenous knowledge related to food preservation and utilization; assess the impact of traditional practices on reducing food waste and its broader implications for sustainable development, and identify key factors influencing the continued use and effectiveness of traditional practices in contemporary African societies. Thus, the study argues that traditional practices and indigenous knowledge in Africa offer valuable insights and strategies for sustainable food waste reduction that can be adapted and integrated into global initiatives This research will employ a mixed-methods approach, combining qualitative and quantitative research techniques. Data collection will involve in-depth interviews, surveys, and participant observations in selected African communities. Moreover, a comprehensive review of literature on traditional food management practices and their impact on food waste reduction will be conducted. The significance of this study lies in its potential to bridge the gap between traditional knowledge and modern sustainability efforts. By uncovering the value of traditional practices in reducing food waste, this research can inform policies, interventions, and awareness campaigns aimed at achieving sustainable food systems worldwide.Keywords: traditional practices, indigenous knowledge, food waste reduction, sustainability
Procedia PDF Downloads 78528 A Study on the Prevalence and Microbiological Profile of Nosocomial Infections in the ICU of a Tertiary Care Hospital in Eastern India
Authors: Pampita Chakraborty, Sukumar Mukherjee
Abstract:
This study was done to determine the prevalence of nosocomial infections in the ICU and to identify the common microorganisms causing these infections and their antimicrobial sensitivity pattern. Nosocomial infection or hospital-acquired infection is a localized or a systemic condition resulting from an adverse reaction to the presence of infectious agents. Nosocomial infections are not present or incubating when the patient is admitted to hospital or other health care facility. They are caused by pathogens that easily spread through the body. Many hospitalized patients have compromised immune systems, so they are less able to fight off infections. These infections occur worldwide, both in the developed and developing the world. They are a significant burden to patients and public health. They are a major cause of death and increased morbidity in hospitalized patients, which is a matter of serious concern today. This study was done during the period of one year (2012-2013) in the ICU of the tertiary care hospital in eastern India. Prevalence of nosocomial infection was determined; site of infection and the pattern of microorganisms were identified along with the assessment of antibiotic susceptibility profile. Patients who developed an infection after 48 hours of admission to the ICU were included in the study. A total of 324 ICU patients were analyzed, of these 79 patients were found to have developed a nosocomial infection (24.3% prevalence). Urinary tract infection was found to be more predominant followed by respiratory tract infection and soft tissue infection. The most frequently isolated microorganism was E. coli, Pseudomonas aeruginosa, Klebsiella pneumoniae followed by other organisms respectively. Antibiotic susceptibility test of these isolates was done against commonly used antibiotics. Patients admitted to the ICU are especially susceptible to nosocomial infections. Despite adequate antimicrobial treatment, nosocomial ICU infections can significantly affect ICU stay and can cause an increase in patient’s morbidity and mortality. Adherence to infection protocol, proper monitoring and the judicious use of antibiotics are important in preventing such infections on a regular basis.Keywords: antibiotic susceptibility, intensive care unit, nosocomial infection, nosocomial pathogen
Procedia PDF Downloads 325527 Effectiveness of Using Multiple Non-pharmacological Interventions to Prevent Delirium in the Hospitalized Elderly
Authors: Yi Shan Cheng, Ya Hui Yeh, Hsiao Wen Hsu
Abstract:
Delirium is an acute state of confusion, which is mainly the result of the interaction of many factors, including: age>65 years, comorbidity, cognitive function and visual/auditory impairment, dehydration, pain, sleep disorder, pipeline retention, general anesthesia and major surgery… etc. Researches show the prevalence of delirium in hospitalized elderly patients over 50%. If it doesn't improve in time, may cause cognitive decline or impairment, not only prolong the length of hospital stay but also increase mortality. Some studies have shown that multiple nonpharmacological interventions are the most effective and common strategies, which are reorientation, early mobility, promoting sleep and nutritional support (including water intake), could improve or prevent delirium in the hospitalized elderly. In Taiwan, only one research to compare the delirium incidence of the older patients who have received orthopedic surgery between multi-nonpharmacological interventions and general routine care. Therefore, the purpose of this study is to address the prevention or improvement of delirium incidence density in medical hospitalized elderly, provide clinical nurses as a reference for clinical implementation, and develop follow-up related research. This study is a quasi-experimental design using purposive sampling. Samples are from two wards: the geriatric ward and the general medicine ward at a medical center in central Taiwan. The sample size estimated at least 100, and then the data will be collected through a self-administered structured questionnaire, including: demographic and professional evaluation items. Case recruiting from 5/13/2023. The research results will be analyzed by SPSS for Windows 22.0 software, including descriptive statistics and inferential statistics: logistic regression、Generalized Estimating Equation(GEE)、multivariate analysis of variance(MANOVA).Keywords: multiple nonpharmacological interventions, hospitalized elderly, delirium incidence, delirium
Procedia PDF Downloads 79526 Accounting for Rice Productivity Heterogeneity in Ghana: The Two-Step Stochastic Metafrontier Approach
Authors: Franklin Nantui Mabe, Samuel A. Donkoh, Seidu Al-Hassan
Abstract:
Rice yields among agro-ecological zones are heterogeneous. Farmers, researchers and policy makers are making frantic efforts to bridge rice yield gaps between agro-ecological zones through the promotion of improved agricultural technologies (IATs). Farmers are also modifying these IATs and blending them with indigenous farming practices (IFPs) to form farmer innovation systems (FISs). Also, different metafrontier models have been used in estimating productivity performances and their drivers. This study used the two-step stochastic metafrontier model to estimate the productivity performances of rice farmers and their determining factors in GSZ, FSTZ and CSZ. The study used both primary and secondary data. Farmers in CSZ are the most technically efficient. Technical inefficiencies of farmers are negatively influenced by age, sex, household size, education years, extension visits, contract farming, access to improved seeds, access to irrigation, high rainfall amount, less lodging of rice, and well-coordinated and synergized adoption of technologies. Albeit farmers in CSZ are doing well in terms of rice yield, they still have the highest potential of increasing rice yield since they had the lowest TGR. It is recommended that government through the ministry of food and agriculture, development partners and individual private companies promote the adoption of IATs as well as educate farmers on how to coordinate and synergize the adoption of the whole package. Contract farming concept and agricultural extension intensification should be vigorously pursued to the latter.Keywords: efficiency, farmer innovation systems, improved agricultural technologies, two-step stochastic metafrontier approach
Procedia PDF Downloads 269525 Flood Inundation Mapping at Wuseta River, East Gojjam Zone, Amhara Regional State, Ethiopia
Authors: Arega Mulu
Abstract:
Flood is a usual phenomenon that will continue to be a leading risk as extensive as societies living and effort in flood-disposed areas. It happens when the size of rainwater in a stream surpasses the volume of the canal. In Ethiopia, municipal overflow events are suitable for severe difficulty in current years. This overflow is mainly related to poorly planned city drainage schemes and land use design. Collective with it, the absence of detailed flood levels, the absence of an early caution scheme and systematized flood catastrophe alleviation actions at countrywide and local levels further raise the gravity of the problem. Hence, this study produces flood inundation maps in the Wuseta River using HEC-GeoRAS and HEC-RAS models. The flooded areas along the Wuseta River have been plotted based on different return periods. The highest flows for various return periods were assessed using the HEC-RAS model, GIS for spatial data processing, and HEC-GeoRAS for interfacing among HEC-RAS and GIS. The areas along the Wuseta River simulated to be flooded for 5, 10, 25, 50, and 100-year return periods. For a 100-year return period flood frequency, the maximum flood depth was 2.26m, and the maximum width was 0.3km on each riverside. This maximum Depth of flood was extended from near to the journey from the university to Debre Markos Town. Most of the area was affected near the Wuseta market to Abaykunu new bridge, and a small portion was affected from Abaykunu to the road crossing from Addis Ababa to Debre Markos Town. The outcome of this study will help the concerned bodies frame and advance policies according to the existing flood risk in the area.Keywords: flood innundation, wuseta river, HEC-HMS, HEC-RAS
Procedia PDF Downloads 8524 Egyptian and Irish Female Protagonists: A Comparative Study of Al-Hakim's Song of Death and Synge's Riders to the Sea
Authors: Ahmed Mohammed Ghaleb, Ehab Saleh Alnuzaili
Abstract:
This paper attempts to generally examine Tawfiq Al-Hakim's Song of Death (1950) and John Millington Synge's Riders to the Sea (1904) by comparatively bringing the two plays under focus. Strikingly, the similarities between the two plays appear in the plot, picturization of the characters, tragic intensity, structural perfection, and the economy of language. Plot structure, albeit a simple one in both plays, is enriched by the playwrights' effective use of language, symbols, imagery, and tragic irony. Neither of the two plays has the traditional five-act structure; they are one-act plays. From a feminist point of view, the domination of female characters is observed in both plays. The female protagonists are the main focus of the two plays. Their brave characters and struggle are highly depicted. While Al-Hakim's protagonist is presented as a victim of tribal customs, Synge's protagonist is shown as a victim of nature. Both plays can be described as 'feminine tragedies' using the words of Oona Frwaley. Although the two plays appeared in totally different historical periods of time, both share considerable similarities, thematic as well as linguistic, which result in a concern to investigate them. The paper, basically, aims at asserting the commonalities between human beings and creating awareness of intercultural negotiations and connections. It attempts to bridge the cultural, intellectual, and social gap between Arab and Irish drama by exploring the common elements of the two plays. Thus, the paper presents a critical and comparative study of both plays highlighting the portrayal of the female protagonists.Keywords: economy of language, imagery, protagonist, symbols, tragic intensity, tragic irony
Procedia PDF Downloads 215523 Challenges to Reaching Higher Education in Developing Countries
Authors: Suhail Shersad
Abstract:
Introduction In developing countries, the access to higher education for the lower socioeconomic strata is very poor at less than 0.05%. The challenges faced by prospective students in these circumstances to pursue higher education have been explored through direct interaction with them and their families in urban slums of New Delhi. This study included evaluation of the demographics, social indices, expectations and perceptions of selected communities. Results The results show that the poor life expectancy, low exposure to technology, lack of social infrastructure and poor sanitary conditions have reduced their drive for academic achievements. This is despite a good level of intelligence and critical thinking skills among these students. The perception of the community including parents shows that despite their desire to excel, there are too may roadblocks to achieving a fruitful professional life for the next generation. Discussion The prerequisites of higher education may have to be revisited to be more inclusive of socially handicapped students. The knowledge, skills and attributes required for higher education system should form the baseline for creating a roadmap for higher secondary education suited for local needs. Conventional parameters like marks and grading have to be re-looked so that life skills and vocational training form part of the core curriculum. Essential skills should be incorporated at an earlier age, providing an alternative pathway for such students to join higher education. Conclusion: There is a need to bridge the disconnect that exists between higher education planning, the needs of the concerned cohorts and the existing higher secondary education. The variables that contribute to making such a decision have to be examined further. Keywords: prerequisites of higher education, social mobility, society expectations, access to higher educationKeywords: access to higher education, prerequisites of higher education, society expectations, social mobility
Procedia PDF Downloads 387522 Determinants of Free Independent Traveler Tourist Expenditures in Israel: Quantile Regression Model
Authors: Shlomit Hon-Snir, Sharon Teitler-Regev, Anabel Lifszyc Friedlander
Abstract:
Tourism, one of the world's largest and fastest growing industries, exerts a major economic influence. The number of international tourists is growing every year, and the relative portion of independent (FIT) tourists is growing as well. The characteristics of independent tourists differ from those of tourists who travel in organized trips. The purpose of the research is to identify the factors that affect the individual tourist's expenses in Israel: total expenses, expenses per day, expenses per tourist, expenses per day per tourist, accommodation expenses, dining expenses and transportation expenses. Most of the research analyzed the total expenses using OLS regression. The determinants influencing expenses were divided into four groups: budget constraints, socio-demographic data, psychological characteristics and travel-related characteristics. Since the effect of each variable may change over different levels of total expenses the quantile regression (QR) theory will be applied. The current research will use data collected by the Israeli Ministry of Tourism in 2015 from individual independent tourists at the end of their visit to Israel. Preliminary results show that: At lower levels of expense, only income has a (positive) effect on total expenses, while at higher levels of expense, both income and length of stay have (positive) effects. -The effect of income on total expenses is higher for higher levels of expenses than for lower level of expenses. -The number of sites visited during the trip has a (negative) effect on tourist accommodation expenses only for tourists with a high level of total expenses. Due to the increasing share of independent tourism in Israel and around the world and due to the importance of tourism to Israel, it is very important to understand the factors that influence the expenses and behavior of independent tourists. Understanding the factors that affect independent tourists' expenses in Israel can help Israeli policymakers in their promotional efforts to attract tourism to Israel.Keywords: independent tourist, quantile regression theory, tourism expenses, tourism
Procedia PDF Downloads 274521 A General Form of Characteristics Method Applied on Minimum Length Nozzles Design
Authors: Merouane Salhi, Mohamed Roudane, Abdelkader Kirad
Abstract:
In this work, we present a new form of characteristics method, which is a technique for solving partial differential equations. Typically, it applies to first-order equations; the aim of this method is to reduce a partial differential equation to a family of ordinary differential equations along which the solution can be integrated from some initial data. This latter developed under the real gas theory, because when the thermal and the caloric imperfections of a gas increases, the specific heat and their ratio do not remain constant anymore and start to vary with the gas parameters. The gas doesn’t stay perfect. Its state equation change and it becomes for a real gas. The presented equations of the characteristics remain valid whatever area or field of study. Here we need have inserted the developed Prandtl Meyer function in the mathematical system to find a new model when the effect of stagnation pressure is taken into account. In this case, the effects of molecular size and intermolecular attraction forces intervene to correct the state equation, the thermodynamic parameters and the value of Prandtl Meyer function. However, with the assumptions that Berthelot’s state equation accounts for molecular size and intermolecular force effects, expressions are developed for analyzing the supersonic flow for thermally and calorically imperfect gas. The supersonic parameters depend directly on the stagnation parameters of the combustion chamber. The resolution has been made by the finite differences method using the corrector predictor algorithm. As results, the developed mathematical model used to design 2D minimum length nozzles under effect of the stagnation parameters of fluid flow. A comparison for air with the perfect gas PG and high temperature models on the one hand and our results by the real gas theory on the other of nozzles shapes and characteristics are made.Keywords: numerical methods, nozzles design, real gas, stagnation parameters, supersonic expansion, the characteristics method
Procedia PDF Downloads 243520 Closed Incision Negative Pressure Therapy Dressing as an Approach to Manage Closed Sternal Incisions in High-Risk Cardiac Patients: A Multi-Centre Study in the UK
Authors: Rona Lee Suelo-Calanao, Mahmoud Loubani
Abstract:
Objective: Sternal wound infection (SWI) following cardiac operation has a significant impact on patient morbidity and mortality. It also contributes to longer hospital stays and increased treatment costs. SWI management is mainly focused on treatment rather than prevention. This study looks at the effect of closed incision negative pressure therapy (ciNPT) dressing to help reduce the incidence of superficial SWI in high-risk patients after cardiac surgery. The ciNPT dressing was evaluated at 3 cardiac hospitals in the United Kingdom". Methods: All patients who had cardiac surgery from 2013 to 2021 were included in the study. The patients were classed as high risk if they have two or more of the recognised risk factors: obesity, age above 80 years old, diabetes, and chronic obstructive pulmonary disease. Patients receiving standard dressing (SD) and patients using ciNPT were propensity matched, and the Fisher’s exact test (two-tailed) and unpaired T-test were used to analyse categorical and continuous data, respectively. Results: There were 766 matched cases in each group. Total SWI incidences are lower in the ciNPT group compared to the SD group (43 (5.6%) vs 119 (15.5%), P=0.0001). There are fewer deep sternal wound infections (14(1.8%) vs. 31(4.04%), p=0.0149) and fewer superficial infections (29(3.7%) vs. 88 (11.4%), p=0.0001) in the ciNPT group compared to the SD group. However, the ciNPT group showed a longer average length of stay (11.23 ± 13 days versus 9.66 ± 10 days; p=0.0083) and higher mean logistic EuroSCORE (11.143 ± 13 versus 8.094 ± 11; p=0.0001). Conclusion: Utilization of ciNPT as an approach to help reduce the incidence of superficial and deep SWI may be effective in high-risk patients requiring cardiac surgery.Keywords: closed incision negative pressure therapy, surgical wound infection, cardiac surgery complication, high risk cardiac patients
Procedia PDF Downloads 99519 Fuzzy Logic for Control and Automatic Operation of Natural Ventilation in Buildings
Authors: Ekpeti Bukola Grace, Mahmoudi Sabar Esmail, Chaer Issa
Abstract:
Global energy consumption has been increasing steadily over the last half - century, and this trend is projected to continue. As energy demand rises in many countries throughout the world due to population growth, natural ventilation in buildings has been identified as a viable option for lowering these demands, saving costs, and also lowering CO2 emissions. However, natural ventilation is driven by forces that are generally unpredictable in nature thus, it is important to manage the resulting airflow in order to maintain pleasant indoor conditions, making it a complex system that necessitates specific control approaches. The effective application of fuzzy logic technique amidst other intelligent systems is one of the best ways to bridge this gap, as its control dynamics relates more to human reasoning and linguistic descriptions. This article reviewed existing literature and presented practical solutions by applying fuzzy logic control with optimized techniques, selected input parameters, and expert rules to design a more effective control system. The control monitors used indoor temperature, outdoor temperature, carbon-dioxide levels, wind velocity, and rain as input variables to the system, while the output variable remains the control of window opening. This is achieved through the use of fuzzy logic control tool box in MATLAB and running simulations on SIMULINK to validate the effectiveness of the proposed system. Comparison analysis model via simulation is carried out, and with the data obtained, an improvement in control actions and energy savings was recorded.Keywords: fuzzy logic, intelligent control systems, natural ventilation, optimization
Procedia PDF Downloads 130518 Tourism and Marketing: An Exploration Study to the Strategic Market Analysis of Moses Mabhida Stadium as a Major Tourism Destination in Kwazulu-Natal
Authors: Nduduzo Andrias Ngxongo, Nsizwazikhona Simon Chili
Abstract:
This analytical exploration illustrates how the non-existence of a proper marketing strategy for a tourism destination may have resulted in a radical decline in both financial outputs and visitor arrivals. The marketing strategy is considered as the foundation for any tourism destination’s marketing tactics. Tourism destinations are ought to have dynamic and adaptive marketing strategies that will develop a promotional approach to help the destination to gain market share, identify its target markets, stay relevant to its existing clients, attract new visitors, and increase profits-earned. Accordingly, the Moses Mabhida Stadium (MMS), one of the prominent tourist attractions in KwaZulu-Natal; boasting a world-class architectural design, several international prestigious awards, and vibrant, adventurous activities, has in recent years suffered a gradual slump in both visitors and profits. Therefore, the basis of this paper was to thoroughly establish precisely how the existing MMS marketing strategy may be a basis for a decline in the number of visitors and profits-earned in recent years. The study adopted mixed method research strategy, with 380 participants. The outcome of the study suggests some costly disparities in the marketing strategy of MMS which has led to poor performance and a loss in tourism market share. In consequence, the outcome further suggests that the non-existence of market research analysis and destination marketing tools contributed vastly to the in-progress dilemma. This fact-finding exploration provides a birds-eye outlook of MMS marketing strategy, and based on the results, the study recommends for the introduction of a more far-reaching and revitalising marketing strategy through; constant and persistent market research initiatives, minimal political interference in the administration of state-funded organisations, reassessment of the feasibility study, vigorous, and sourcing of proficient personnel.Keywords: tourism, destination, marketing , marketing strategy
Procedia PDF Downloads 271517 Public Debt Shocks and Public Goods Provisioning in Nigeria: Implication for National Development
Authors: Amenawo I. Offiong, Hodo B. Riman
Abstract:
Public debt profile of Nigeria has continuously been on the increase over the years. The drop in international crude oil prices has further worsened revenue position of the country, thus, necessitating further acquisition of public debt to bridge the gap in revenue deficit. Yet, when we look back at the increasing public sector spending, there are concerns that the government spending do not amount to increase in public goods provided for the country. Using data from 1980 to 2014 the study therefore seeks to investigate the factors responsible for the poor provision of public goods in the face of increasing public debt profile. Using the unrestricted VAR model Governance and Tax revenue were introduced into the model as structural variables. The result suggested that governance and tax revenue were structural determinants of the effectiveness of public goods provisioning in Nigeria. The study therefore identified weak governance as the major reason for the non-provision of public goods in Nigeria. While tax revenue exerted positive influence on the provisions of public goods, weak/poor governance was observed to crowd the benefits from increase tax revenue. The study therefore recommends reappraisal of the governance system in Nigeria. Elected officers in governance should be more transparent and accountable to the electorates they represent. Furthermore, the study advocates for an annual auditing of all government MDAs accounts by external auditors to ensure (a) accountability of public debts utilization, (b) transparent in implementation of program support funds, (c) integrity of agencies responsible for program management, and (d) measuring program effectiveness with amount of funds expended.Keywords: impulse response function, public debt shocks, governance, public goods, tax revenue, vector auto-regression
Procedia PDF Downloads 275516 InAs/GaSb Superlattice Photodiode Array ns-Response
Abstract:
InAs/GaSb type-II superlattice (T2SL) Mid-wave infrared (MWIR) focal plane arrays (FPAs) have recently seen rapid development. However, in small pixel size large format FPAs, the occurrence of high mesa sidewall surface leakage current is a major constraint necessitating proper surface passivation. A simple pixel isolation technique in InAs/GaSb T2SL detector arrays without the conventional mesa etching has been proposed to isolate the pixels by forming a more resistive higher band gap material from the SL, in the inter-pixel region. Here, a single step femtosecond (fs) laser anneal of the T2SL structure of the inter-pixel T2SL regions, have been used to increase the band gap between the pixels by QW-intermixing and hence increase isolation between the pixels. The p-i-n photodiode structure used here consists of a 506nm, (10 monolayer {ML}) InAs:Si (1x10¹⁸cm⁻³)/(10ML) GaSb SL as the bottom n-contact layer grown on an n-type GaSb substrate. The undoped absorber layer consists of 1.3µm, (10ML)InAs/(10ML)GaSb SL. The top p-contact layer is a 63nm, (10ML)InAs:Be(1x10¹⁸cm⁻³)/(10ML)GaSb T2SL. In order to improve the carrier transport, a 126nm of graded doped (10ML)InAs/(10ML)GaSb SL layer was added between the absorber and each contact layers. A 775nm 150fs-laser at a fluence of ~6mJ/cm² is used to expose the array where the pixel regions are masked by a Ti(200nm)-Au(300nm) cap. Here, in the inter-pixel regions, the p+ layer have been reactive ion etched (RIE) using CH₄+H₂ chemistry and removed before fs-laser exposure. The fs-laser anneal isolation improvement in 200-400μm pixels due to spatially selective quantum well intermixing for a blue shift of ~70meV in the inter-pixel regions is confirmed by FTIR measurements. Dark currents are measured between two adjacent pixels with the Ti(200nm)-Au(300nm) caps used as contacts. The T2SL quality in the active photodiode regions masked by the Ti-Au cap is hardly affected and retains the original quality of the detector. Although, fs-laser anneal of p+ only etched p-i-n T2SL diodes show a reduction in the reverse dark current, no significant improvement in the full RIE-etched mesa structures is noticeable. Hence for a 128x128 array fabrication of 8μm square pixels and 10µm pitch, SU8 polymer isolation after RIE pixel delineation has been used. X-n+ row contacts and Y-p+ column contacts have been used to measure the optical response of the individual pixels. The photo-response of these 8μm and other 200μm pixels under a 2ns optical pulse excitation from an Optical-Parametric-Oscillator (OPO), shows a peak responsivity of ~0.03A/W and 0.2mA/W, respectively, at λ~3.7μm. Temporal response of this detector array is seen to have a fast response ~10ns followed typical slow decay with ringing, attributed to impedance mismatch of the connecting co-axial cables. In conclusion, response times of a few ns have been measured in 8µm pixels of a 128x128 array. Although fs-laser anneal has been found to be useful in increasing the inter-pixel isolation in InAs/GaSb T2SL arrays by QW inter-mixing, it has not been found to be suitable for passivation of full RIE etched mesa structures with vertical walls on InAs/GaSb T2SL.Keywords: band-gap blue-shift, fs-laser-anneal, InAs/GaSb T2SL, Inter-pixel isolation, ns-Response, photodiode array
Procedia PDF Downloads 153515 Income Inequality among Selected Entrepreneurs in Ondo State, Nigeria
Authors: O.O. Ehinmowo, A.I. Fatuase, D.F. Oke
Abstract:
Nigeria is endowed with resources that could boost the economy as well as generate income and provide jobs to the teaming populace. One of the keys of attaining this is by making the environment conducive for the entrepreneurs to excel in their respective enterprises so that more income could be accrued to the entrepreneurs. This study therefore examines income inequality among selected entrepreneurs in Ondo State, Nigeria using primary data. A multistage sampling technique was used to select 200 respondents for the study with the aid of structured questionnaire and personal interview. The data collected were subjected to descriptive statistics, Lorenz curve, Gini coefficient and Double - Log regression model. Results revealed that majority of the entrepreneurs (63%) were males and 90% were married with an average age of 44 years. About 40% of the respondents spent at most 12 years in school with 81% of the respondents had 4-6 members per household, while hair dressing (43.5%) and fashion designing (31.5%) were the most common enterprises among the sampled respondents. The findings also showed that majority of the entrepreneurs in hairdressing, fashion designing and laundry service earned below N200,000 per annum while the majority of those in restaurant and food vending earned between N400,000 – N600,000 followed by the entrepreneurs in pure water enterprise where majority earned N800,000 and above per annum. The result of the Gini coefficient (0.58) indicated that there was presence of inequality among the entrepreneurs which was also affirmed by the Lorenz curve. The Regression results showed that gender, household size and number of employees significantly affected the income of the entrepreneurs in the study area. Therefore, more female households should be encouraged into entrepreneurial businesses and government should give incentive cum conductive environment that could bridge the disparity in the income of the entrepreneurs in their various enterprises.Keywords: entrepreneurs, Gini coefficient, income inequality, Lorenz curve
Procedia PDF Downloads 352514 Reallocation of Bed Capacity in a Hospital Combining Discrete Event Simulation and Integer Linear Programming
Authors: Muhammed Ordu, Eren Demir, Chris Tofallis
Abstract:
The number of inpatient admissions in the UK has been significantly increasing over the past decade. These increases cause bed occupancy rates to exceed the target level (85%) set by the Department of Health in England. Therefore, hospital service managers are struggling to better manage key resource such as beds. On the other hand, this severe demand pressure might lead to confusion in wards. For example, patients can be admitted to the ward of another inpatient specialty due to lack of resources (i.e., bed). This study aims to develop a simulation-optimization model to reallocate the available number of beds in a mid-sized hospital in the UK. A hospital simulation model was developed to capture the stochastic behaviours of the hospital by taking into account the accident and emergency department, all outpatient and inpatient services, and the interactions between each other. A couple of outputs of the simulation model (e.g., average length of stay and revenue) were generated as inputs to be used in the optimization model. An integer linear programming was developed under a number of constraints (financial, demand, target level of bed occupancy rate and staffing level) with the aims of maximizing number of admitted patients. In addition, a sensitivity analysis was carried out by taking into account unexpected increases on inpatient demand over the next 12 months. As a result, the major findings of the approach proposed in this study optimally reallocate the available number of beds for each inpatient speciality and reveal that 74 beds are idle. In addition, the findings of the study indicate that the hospital wards will be able to cope with 14% demand increase at most in the projected year. In conclusion, this paper sheds a new light on how best to reallocate beds in order to cope with current and future demand for healthcare services.Keywords: bed occupancy rate, bed reallocation, discrete event simulation, inpatient admissions, integer linear programming, projected usage
Procedia PDF Downloads 144513 Surgical Treatment Tumors and Cysts of the Pancreas in Children
Authors: Trunov V.O., Ryabov A. B., Poddubny I.V
Abstract:
Introduction: cystic and solid pancreatic tumors have a relevant and disruptive position in many positions. The results of the treatment of children with tumors and pancreatic cysts aged 3 to 17 years for the period from 2008 to 2019 on the basis of the Morozov State Children's Clinical Hospital in Moscow were analyzed. The total number of children with solid tumors was 17, and 31 with cysts. In all children, the diagnosis was made on the basis of ultrasound, followed by CT and MRI. In most patients with solid tumors, they were located in the area of the pancreas tail - 58%, in the body area - 14%, in the area of the pancreatic head - 28%. In patients with pancreatic cysts, the distribution of patients by topography was as follows: head of the pancreas - 10%, body of the pancreas - 16%, tail of the pancreas - 68%, total cystic transformation of the Wirsung duct - 6%. In pancreatic cysts, the method of surgical treatment was based on the results of MRCP, the level of amylase in the contents of the cyst, and the localization of the cyst. Thus, pathogenetically substantiated treatment included: excision of cysts, internal drainage on an isolated loop according to Ru, the formation of pancreatojejunoanastomosis in a child with the total cystic transformation of the Wirsung duct. In patients with solid pancreatic lesions, pancretoduodenalresection, central resection of the pancreas, and distal resection from laparotomy and laparoscopic access were performed. In the postoperative period, in order to prevent pancreatitis, all children underwent antisecretory therapy, parenteral nutrition, and drainage of the omental bursa. Results: hospital stay ranged from 7 to 12 days. The duration of postoperative fermentemia in patients with solid formations lasted from 3 to 6 days. In all cases, according to the histological examination, a pseudopapillary tumor of the pancreas was revealed. In the group of children with pancreatic cysts, fermentemia was observed from 2 to 4 days, recurrence of cysts in the long term was detected in 3 children (10%). Conclusions: the treatment of cystic and solid pancreatic neoplasms is a difficult task in connection with the anatomical and functional features of the organ.Keywords: pancreas, tumors, cysts, resection, laparoscopy, children
Procedia PDF Downloads 141512 Lactate in Critically Ill Patients an Outcome Marker with Time
Authors: Sherif Sabri, Suzy Fawzi, Sanaa Abdelshafy, Ayman Nagah
Abstract:
Introduction: Static derangements in lactate homeostasis during ICU stay have become established as a clinically useful marker of increased risk of hospital and ICU mortality. Lactate indices or kinetic alteration of the anaerobic metabolism make it a potential parameter to evaluate disease severity and intervention adequacy. This is an inexpensive and simple clinical parameter that can be obtained by a minimally invasive means. Aim of work: Comparing the predictive value of dynamic indices of hyperlactatemia in the first twenty four hours of intensive care unit (ICU) admission with other static values are more commonly used. Patients and Methods: This study included 40 critically ill patients above 18 years old of both sexes with Hyperlactamia (≥ 2 m mol/L). Patients were divided into septic group (n=20) and low oxygen transport group (n=20), which include all causes of low-O2. Six lactate indices specifically relating to the first 24 hours of ICU admission were considered, three static indices and three dynamic indices. Results: There were no statistically significant differences among the two groups regarding age, most of the laboratory results including ABG and the need for mechanical ventilation. Admission lactate was significantly higher in low-oxygen transport group than the septic group [37.5±11.4 versus 30.6±7.8 P-value 0.034]. Maximum lactate was significantly higher in low-oxygen transport group than the septic group P-value (0.044). On the other hand absolute lactate (mg) was higher in septic group P-value (< 0.001). Percentage change of lactate was higher in the septic group (47.8±11.3) than the low-oxygen transport group (26.1±12.6) with highly significant P-value (< 0.001). Lastly, time weighted lactate was higher in the low-oxygen transport group (1.72±0.81) than the septic group (1.05±0.8) with significant P-value (0.012). There were statistically significant differences regarding lactate indices in survivors and non survivors, whether in septic or low-oxygen transport group. Conclusion: In critically ill patients, time weighted lactate and percent in lactate change in the first 24 hours can be an independent predictive factor in ICU mortality. Also, a rising compared to a falling blood lactate concentration over the first 24 hours can be associated with significant increase in the risk of mortality.Keywords: critically ill patients, lactate indices, mortality in intensive care, anaerobic metabolism
Procedia PDF Downloads 242511 Shaking the Iceberg: Metaphoric Shifting and Loss in the German Translations of 'The Sun Also Rises'
Authors: Christopher Dick
Abstract:
While the translation of 'literal language' poses numerous challenges for the translator, the translation of 'figurative language' creates even more complicated issues. It has been only in the last several decades that scholars have attempted to propose theories of figurative language translation, including metaphor translation. Even less work has applied these theories to metaphoric translation in literary texts. And almost no work has linked an analysis of metaphors in translation with the recent scholarship on conceptual metaphors. A study of literature in translation must not only examine the inevitable shifts that occur as specific metaphors move from source language to target language but also analyze the ways in which these shifts impact conceptual metaphors and, ultimately, the text as a whole. Doing so contributes to on-going efforts to bridge the sometimes wide gulf between considerations of content and form in literary studies. This paper attempts to add to the body of scholarly literature on metaphor translation and the function of metaphor in a literary text. Specifically, the study examines the metaphoric expressions in Hemingway’s The Sun Also Rises. First, the issue of Hemingway and metaphor is addressed. Next, the study examines the specific metaphors in the original novel in English and the German translations, first in Annemarie Horschitz’s 1928 German version and then in the recent Werner Schmitz 2013 translation. Hemingway’s metaphors, far from being random occurrences of figurative language, are linguistic manifestations of deeper conceptual metaphors that are central to an interpretation of the text. By examining the modifications that are made to these original metaphoric expressions as they are translated into German, one can begin to appreciate the shifts involved with metaphor translation. The translation of Hemingway’s metaphors into German represents significant metaphoric loss and shifting that subsequently shakes the important conceptual metaphors in the novel.Keywords: Hemingway, Conceptual Metaphor, Translation, Stylistics
Procedia PDF Downloads 358510 Regional Anesthesia: A Vantage Point for Management of Normal Pressure Hydrocephalus
Authors: Kunal K. S., Shwetashri K. R., Keerthan G., Ajinkya R.
Abstract:
Background: Normal pressure hydrocephalus is a condition caused by abnormal accumulation of cerebrospinal fluid (CSF) within the brain resulting in enlarged cerebral ventricles due to a disruption of CSF formation, absorption, or flow. Over the course of time, ventriculoperitoneal shunt under general anesthesia has become a standard of care. Yet only a finite number of centers have started the inclusion of regional anesthesia techniques for the such patient cohort. Stem Case: We report a case of a 75-year-old male with underlying aortic sclerosis and cardiomyopathy who presented with complaints of confusion, forgetfulness, and difficulty in walking. Neuro-imaging studies revealed disproportionally enlarged subarachnoid space hydrocephalus (DESH). The baseline blood pressure was 116/67 mmHg with a heart rate of 106 beats/min and SpO2 of 96% on room air. The patient underwent smooth induction followed by sonographically guided superficial cervical plexus block and transverse abdominis plane block. Intraoperative pain indices were monitored with Analgesia nociceptive index monitor (ANI, MdolorisTM) and surgical plethysmographic index (SPI, GE Healthcare, Helsinki, FinlandTM). These remained stable during the application of the block and the entire surgical duration. No significant hemodynamic response was observed during the tunneling of the skin by the surgeon. The patient underwent a smooth recovery and emergence. Conclusion: Our decision to incorporate peripheral nerve blockade in conjunction with general anesthesia resulted in opioid-sparing anesthesia and decreased post-operative analgesic requirement by the patient. This blockade was successful in suppressing intraoperative stress responses. Our patient recovered adequately and underwent an uncomplicated post-operative stay.Keywords: desh, NPH, VP shunt, cervical plexus block, transversus abdominis plane block
Procedia PDF Downloads 82509 Determinants of Cessation of Exclusive Breastfeeding in Ankesha Guagusa Woreda, Awi Zone, Northwest Ethiopia: A Cross-Sectional Study
Authors: Tebikew Yeneabat, Tefera Belachew, Muluneh Haile
Abstract:
Background: Exclusive breast-feeding (EBF) is the practice of feeding only breast milk (including expressed breast milk) during the first six months and no other liquids and solid foods except medications. The time to cessation of exclusive breast-feeding, however, is different in different countries depending on different factors. Studies showed the risk of diarrhea morbidity and mortality is higher among none exclusive breast-feeding infants, common during starting other foods. However, there is no study that evaluated the time to cessation of exclusive breast-feeding in the study area. The aim of this study was to show time to cessation of EBF and its predictors among mothers of index infants less than twelve months old. Methods: We conducted a community-based cross-sectional study from February 13 to March 3, 2012 using both quantitative and qualitative methods. This study included a total of 592 mothers of index infant using multi-stage sampling method. Data were collected by using interviewer administered structured questionnaire. Bivariate and multivariate Cox regression analyses were performed. Results: Cessation of exclusive breast-feeding occurred in 392 (69.63%) cases. Among these, 224 (57.1%) happened before six months, while 145 (37.0%) and 23 (5.9%) occurred at six months and after six months of age of the index infant respectively. The median time for infants to stay on exclusive breast-feeding was 6.36 months in rural and 5.13 months in urban, and this difference was statistically significant on a Log rank (Cox-mantel) test. Maternal and paternal occupation, place of residence, postnatal counseling on exclusive breast-feeding, mode of delivery, and birth order of the index infant were significant predictors of cessation of exclusive breast-feeding. Conclusion: Providing postnatal care counseling on EBF, routine follow-up and support of those mothers having infants stressing for working mothers can bring about implementation of national strategy on infant and young child feeding.Keywords: exclusive breastfeeding, cessation, median duration, Ankesha Guagusa Woreda
Procedia PDF Downloads 319508 The Implementation of Teaching and Learning Quality Assurance System at the Chaoyang University of Technology for Academic Year 2013-2015
Authors: Ting Hsiang Chang
Abstract:
Nowadays in Taiwan, higher education, which was previously more emphasized on teaching-oriented approaches, has gradually shifted to an approach more focusing on students learning outcomes. With student employment rate as an important indicator for University Program Evaluation periodically held by the Ministry of Education, it becomes extremely critical for a university to build up a teaching and learning quality assurance system to bridge the gap between learning and practice. Teaching and Learning Quality Assurance System has been built and implemented at Chaoyang University of Technology for years and has received substantial results. By employing various forms of evaluation and performance appraisals, the effectiveness of teaching and learning can consistently be tracked as a means of ensuring teaching and learning quality. This study aims to explore the evaluation system of teaching and learning quality assurance system at the Chaoyang University of Technology by means of content analysis. The study contents the evaluation reports on the teaching and learning quality assurance at the Chaoyang University of Technology in the Academic Year 2013-2015. The quantitative results of the assessment were analyzed using the five-point Likert Scale. Quality assurance Committee meetings were further held for examining and discussions on the results. To the end, the annual evaluation report is to be produced as references used to improve approaches in both teaching and learning. The findings indicate that there is a respective relationship between the overall teaching evaluation items and the teaching goals and core competencies. In addition, graduates’ feedbacks were also collected for further analysis to examine if the current educational planning is able to achieve the university’s teaching goal and cultivation of core competencies.Keywords: core competencies, teaching and learning quality assurance system, teaching goals, university program evaluation
Procedia PDF Downloads 293507 Sense of Involvement and Support in Persons with Cognitive Decline in Ordinary Dwelling
Authors: Annika Kjallman Alm, Ove Hellzen, Malin Rising-Holmstrom
Abstract:
Worldwide, the number of people who are living with dementia is increasing because of an aging population, which leads to increased financial and social costs, including reduced quality of life for people with dementia and their care partners. Most people who have dementia reside in the community. Aging in place could be described as having the health and social supports and services you need to live safely and independently in your home or your society for as long as you wish and are able. People with dementia are not different than people without dementia where they want to remain at home, if possible, with a sense of familiarity and engagement in typical everyday activities. So how do persons with dementia or cognitive decline see their possibilities to be socially involved and experience support? The aim of this study was to explore persons with cognitive decline's sense of involvement and support living in the ordinary dwelling. The study was approved by the Ethical Review Authority in Sweden prior to the interviews. Interviews were conducted with 20 persons living at home, either alone or in a relationship. The persons had perceived cognitive decline; some were under investigation or already had a diagnose of early dementia. Thematic analysis was used to identify, analyze, and report patterns within the data. Researchers extracted three main themes through participants’ interviews: a) Importance of social involvement with family and friends. b) Hindrances for social involvement. c) Struggling mentally with a new life situation. Results found that going to activity centers, staying involved, and meeting friends and family enhanced the sense of involvement and support. There were also hindrances to a sense of involvement and support as they struggled with the diagnose and the changes in daily life, such as physical problems, mental problems, or economic issues. The mental struggle of accepting the cognitive decline and the changes in daily life it brought was also an issue for some of the participants. A multidimensional support should be provided by the community to enable persons with cognitive decline to stay involved in family and community in the comfort of their own homes.Keywords: aging in place, cognitive decline, dementia, sense of involvement
Procedia PDF Downloads 141506 Winning the Future of Education in Africa through Project Base Learning: How the Implementation of PBL Pedagogy Can Transform Africa’s Educational System from Theory Base to Practical Base in School Curriculum
Authors: Bismark Agbemble
Abstract:
This paper talks about how project-based learning (PBL) is being infused or implemented in the educational sphere of Africa. The paper navigates through the liminal aspects of PBL as a pedagogical approach to bridge the divide between theoretical knowledge and its application within school curriculums. Given that contextualized learning can be embodied, the abstract vehemently discusses that PBL creates an opportunity for students to work on projects that are of academic relevance in their local settings. It presents PBL’s growth of critical thinking, problem-solving, cooperation, and communications, which is vital in getting young citizens to prepare for the 21st-century revolution. In addition, the abstract stresses the possibility that PBL could become a stimulus to creativity and innovation wherein learning becomes motivated from within by intrinsic motivations. The paper advocates for a holistic approach that is based on teacher’s professional development with the provision of adequate infrastructural facilities and resource allocation, thus ensuring the success and sustainability of PBLs in African education systems. In the end, the paper positions this as a transformative educational methodology that has great potential in helping to shape an African generation that is prepared for a great future.Keywords: student centered pedagogy, constructivist learning theory, self-directed learning, active exploration, real world challenges, STEM, 21st century skills, curriculum design, classroom management, project base learning curriculum, global intelligence, social and communication skills, transferable skills, critical thinking, investigatable learning, life skills
Procedia PDF Downloads 58505 Development of Regional Cooperation to Sustainable Implementation of Customary Refugee Solutions in International Arena
Authors: Md. Reduanul Haque
Abstract:
In recent time, more and more refugees are emerging in the international arena than the times ever that has come into the notice of world scholars. The prevailing customary solutions such as voluntary repatriation, local integration, and resettlement of refugee problem have been reflected unsustainable one for the lack of regional cooperation. In the international arena, the protraction of refugee problems is seen, and refugees are suffering due to the outrageous process of customary refugee solutions. If the regional cooperation can be developed, then the suffering of the refugees can be mitigated by the contribution of neighboring country and international and regional organizations. Data collected from the various secondary sources have been used throughout the research. It has been discussing in the refugee academia for a long time to develop regional cooperation mechanisms to ensure the sustainability of this solution and to make the environment of the country of origin for suitable voluntary repatriation as well as a durable solution. It is mainly qualitative research based on primary and secondary data will be studied on library-based project. Data collected by such methodology on this study indicates to make a bridge between the gaps of the cooperation mechanism and to make a more regional approach to share the burden and to strengthen the customary refugee solution. Hence, the importance of questing for a regional mechanism is to ensure the responsible countries to be more responsible towards refugees, their human rights, and durable solution under the mandate of the UNHCR. To implement effectively all the customary durable solutions, country to country or regional organization to organization based regional cooperation can be developed where the countries and regional organizations will work together to draw a sustainable solution to this problem in international context.Keywords: refugee, regional cooperation, sustainable implementation, customary solutions, international arena
Procedia PDF Downloads 144504 Surface Tension and Bulk Density of Ammonium Nitrate Solutions: A Molecular Dynamics Study
Authors: Sara Mosallanejad, Bogdan Z. Dlugogorski, Jeff Gore, Mohammednoor Altarawneh
Abstract:
Ammonium nitrate (NH₄NO₃, AN) is commonly used as the main component of AN emulsion and fuel oil (ANFO) explosives, that use extensively in civilian and mining operations for underground development and tunneling applications. The emulsion formulation and wettability of AN prills, which affect the physical stability and detonation of ANFO, highly depend on the surface tension, density, viscosity of the used liquid. Therefore, for engineering applications of this material, the determination of density and surface tension of concentrated aqueous solutions of AN is essential. The molecular dynamics (MD) simulation method have been used to investigate the density and the surface tension of high concentrated ammonium nitrate solutions; up to its solubility limit in water. Non-polarisable models for water and ions have carried out the simulations, and the electronic continuum correction model (ECC) uses a scaling of the charges of the ions to apply the polarisation implicitly into the non-polarisable model. The results of calculated density and the surface tension of the solutions have been compared to available experimental values. Our MD simulations show that the non-polarisable model with full-charge ions overestimates the experimental results while the reduce-charge model for the ions fits very well with the experimental data. Ions in the solutions show repulsion from the interface using the non-polarisable force fields. However, when charges of the ions in the original model are scaled in line with the scaling factor of the ECC model, the ions create a double ionic layer near the interface by the migration of anions toward the interface while cations stay in the bulk of the solutions. Similar ions orientations near the interface were observed when polarisable models were used in simulations. In conclusion, applying the ECC model to the non-polarisable force field yields the density and surface tension of the AN solutions with high accuracy in comparison to the experimental measurements.Keywords: ammonium nitrate, electronic continuum correction, non-polarisable force field, surface tension
Procedia PDF Downloads 233503 Health Tourists in Iran and Cultural Prejudices
Authors: Naeemeh Silvari
Abstract:
The tourism industry is important for different nations in two ways. Apart from economic benefits, it provides a basis for getting acquainted with the culture of different regions of the world. Depending on the capacities and contexts of their geography, countries try to attract more people to their country in different ways. Health tourism has been an important branch of the tourism industry in recent years, and many countries around the world are trying to make progress in this field and attract many tourists from around the world. Iran, like many developing countries in the Middle East and East Asia, is trying to improve and develop tourist attractions in the field of health. Due to the cheapness of providing medical services to tourists, many people have traveled to Iran for medical and health care. However, there is a long way to go before recognizing and reaching the desired position in this field. Due to the direct relationship between tourism and culture, the negative attitude towards the context of Iran has caused foreign travelers not to choose this country as their tourist destination. In this article, we tried to study the change in their attitude towards Iran by using semi-structured interviews of foreign travelers who traveled to Iran for treatment and medical services. The text of the interviews was coded and analyzed by MAX QDA software. Many of the people in the sample were from Middle Eastern and Arabic-speaking countries. Influenced by the media, they felt rejected by the Iranians before the trip. During their stay in Iran and in connection with the health care staff, in the first stage, they pointed out that many of their anxieties about the kind of treatment of Iranians have been allayed. In addition to the satisfaction with the medical services provided, they considered the atmosphere of Iranians' interaction with foreign travelers to be relatively appropriate, and some stated that Iran would be the destination of their leisure trip in the future. At the end of the research, policymakers were suggested that in order to resolve cultural contradictions rooted in values, they should first be recognized and seek to use other opportunities to resolve contradictions and form interactions with other cultures.Keywords: cultural conflict, health tourism, cultural prejudice, advertising and media
Procedia PDF Downloads 78502 A Study of the Effects of Zimbabwean Youth Migration on Musina Area, South Africa
Authors: R. Chinyakata, N. R. Raselekoane
Abstract:
Migration has always been part of human history. Migration is spurred by globalisation which connects nations by encouraging the flow of goods, services, ideas and people across borders. Migration does not only involve movement of adults from one country to another. It also affects and involves the youth as they are the most mobile group. Musina area, like many other border areas, experiences a variety of challenges as a result of the influx of people from the neighbouring Zimbabwe and other African countries. Of great concern about this migration is the fact that the host country or area may become unsafe and unstable as a result of huge influx of migrants. There may also be tensions between local people and migrants over the resources. The study sought to investigate the effects of the Zimbabwean youth migration on Musina area. The study was undertaken in Musina area which is situated 18km from the Beit-Bridge border post. A qualitative research approach was used. Semi-structured interviews were used to collect data. Non-probability quota sampling technique was used to select the respondents. The study sample consisted of sixteen female and male respondents. Thematic coding was used to analyse the data. Ethical considerations such as informed consent, confidentiality, anonymity and voluntary participation were taken into account to protect the participants. The study found that the effects of the Zimbabwean youth migration on the Musina area include, among others, tensions between locals and the Zimbabwean youth migrants over resources, job and business opportunities, overcrowding and crime. Multi-pronged strategies which involve different stakeholders should be applied to address tensions over job and business opportunities, overcrowding and crime in the Musina area.Keywords: host country, effects, migrant, migration, Musina, youth, Zimbabwe
Procedia PDF Downloads 245501 Monitoring of the Chillon Viaducts after Rehabilitation with Ultra High Performance Fiber Reinforced Cement-Based Composite
Authors: Henar Martín-Sanz García, Eleni Chatzi, Eugen Brühwiler
Abstract:
Located on the shore of Geneva Lake, in Switzerland, the Chillon Viaducts are two parallel structures consisted of post-tensioned concrete box girders, with a total length of 2 kilometers and 100m spans. Built in 1969, the bridges currently accommodate a traffic load of 50.000 vehicles per day, thereby holding a key role both in terms of historic value as well as socio-economic significance. Although several improvements have been carried out in the past two decades, recent inspections demonstrate an Alkali-Aggregate reaction in the concrete deck and piers reducing the concrete strength. In order to prevent further expansion of this issue, a layer of 40 mm of Ultra High Performance Fiber Reinforced cement-based Composite (UHPFRC) (incorporating rebars) was casted over the slabs, acting as a waterproof membrane and providing significant increase in resistance of the bridge structure by composite UHPFRC – RC composite action in particular of the deck slab. After completing the rehabilitation works, a Structural Monitoring campaign was installed on the deck slab in one representative span, based on accelerometers, strain gauges, thermal and humidity sensors. This campaign seeks to reveal information on the behavior of UHPFRC-concrete composite systems, such as increase in stiffness, fatigue strength, durability and long-term performance. Consequently, the structural monitoring is expected to last for at least three years. A first insight of the analyzed results from the initial months of measurements is presented herein, along with future improvements or necessary changes on the deployment.Keywords: composite materials, rehabilitation, structural health monitoring, UHPFRC
Procedia PDF Downloads 282500 Wideband Performance Analysis of C-FDTD Based Algorithms in the Discretization Impoverishment of a Curved Surface
Authors: Lucas L. L. Fortes, Sandro T. M. Gonçalves
Abstract:
In this work, it is analyzed the wideband performance with the mesh discretization impoverishment of the Conformal Finite Difference Time-Domain (C-FDTD) approaches developed by Raj Mittra, Supriyo Dey and Wenhua Yu for the Finite Difference Time-Domain (FDTD) method. These approaches are a simple and efficient way to optimize the scattering simulation of curved surfaces for Dielectric and Perfect Electric Conducting (PEC) structures in the FDTD method, since curved surfaces require dense meshes to reduce the error introduced due to the surface staircasing. Defined, on this work, as D-FDTD-Diel and D-FDTD-PEC, these approaches are well-known in the literature, but the improvement upon their application is not quantified broadly regarding wide frequency bands and poorly discretized meshes. Both approaches bring improvement of the accuracy of the simulation without requiring dense meshes, also making it possible to explore poorly discretized meshes which bring a reduction in simulation time and the computational expense while retaining a desired accuracy. However, their applications present limitations regarding the mesh impoverishment and the frequency range desired. Therefore, the goal of this work is to explore the approaches regarding both the wideband and mesh impoverishment performance to bring a wider insight over these aspects in FDTD applications. The D-FDTD-Diel approach consists in modifying the electric field update in the cells intersected by the dielectric surface, taking into account the amount of dielectric material within the mesh cells edges. By taking into account the intersections, the D-FDTD-Diel provides accuracy improvement at the cost of computational preprocessing, which is a fair trade-off, since the update modification is quite simple. Likewise, the D-FDTD-PEC approach consists in modifying the magnetic field update, taking into account the PEC curved surface intersections within the mesh cells and, considering a PEC structure in vacuum, the air portion that fills the intersected cells when updating the magnetic fields values. Also likewise to D-FDTD-Diel, the D-FDTD-PEC provides a better accuracy at the cost of computational preprocessing, although with a drawback of having to meet stability criterion requirements. The algorithms are formulated and applied to a PEC and a dielectric spherical scattering surface with meshes presenting different levels of discretization, with Polytetrafluoroethylene (PTFE) as the dielectric, being a very common material in coaxial cables and connectors for radiofrequency (RF) and wideband application. The accuracy of the algorithms is quantified, showing the approaches wideband performance drop along with the mesh impoverishment. The benefits in computational efficiency, simulation time and accuracy are also shown and discussed, according to the frequency range desired, showing that poorly discretized mesh FDTD simulations can be exploited more efficiently, retaining the desired accuracy. The results obtained provided a broader insight over the limitations in the application of the C-FDTD approaches in poorly discretized and wide frequency band simulations for Dielectric and PEC curved surfaces, which are not clearly defined or detailed in the literature and are, therefore, a novelty. These approaches are also expected to be applied in the modeling of curved RF components for wideband and high-speed communication devices in future works.Keywords: accuracy, computational efficiency, finite difference time-domain, mesh impoverishment
Procedia PDF Downloads 135