Search results for: average bubble droplet
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4936

Search results for: average bubble droplet

3586 Cluster Analysis and Benchmarking for Performance Optimization of a Pyrochlore Processing Unit

Authors: Ana C. R. P. Ferreira, Adriano H. P. Pereira

Abstract:

Given the frequent variation of mineral properties throughout the Araxá pyrochlore deposit, even if a good homogenization work has been carried out before feeding the processing plants, an operation with quality and performance’s high variety standard is expected. These results could be improved and standardized if the blend composition parameters that most influence the processing route are determined, and then the types of raw materials are grouped by them, finally presenting a great reference with operational settings for each group. Associating the physical and chemical parameters of a unit operation through benchmarking or even an optimal reference of metallurgical recovery and product quality reflects in the reduction of the production costs, optimization of the mineral resource, and guarantee of greater stability in the subsequent processes of the production chain that uses the mineral of interest. Conducting a comprehensive exploratory data analysis to identify which characteristics of the ore are most relevant to the process route, associated with the use of Machine Learning algorithms for grouping the raw material (ore) and associating these with reference variables in the process’ benchmark is a reasonable alternative for the standardization and improvement of mineral processing units. Clustering methods through Decision Tree and K-Means were employed, associated with algorithms based on the theory of benchmarking, with criteria defined by the process team in order to reference the best adjustments for processing the ore piles of each cluster. A clean user interface was created to obtain the outputs of the created algorithm. The results were measured through the average time of adjustment and stabilization of the process after a new pile of homogenized ore enters the plant, as well as the average time needed to achieve the best processing result. Direct gains from the metallurgical recovery of the process were also measured. The results were promising, with a reduction in the adjustment time and stabilization when starting the processing of a new ore pile, as well as reaching the benchmark. Also noteworthy are the gains in metallurgical recovery, which reflect a significant saving in ore consumption and a consequent reduction in production costs, hence a more rational use of the tailings dams and life optimization of the mineral deposit.

Keywords: mineral clustering, machine learning, process optimization, pyrochlore processing

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3585 Performance Management in Public Administration on Chile and Portugal

Authors: Lilian Bambirra De Assis, Patricia Albuquerque Gomes, Kamila Pagel De Oliveira, Deborah Oliveira Santos, Marcelo Esteves Chaves Campos

Abstract:

This paper aimed to analyze how performance management occurs in the context of the modernization of the federal public sector in Chile and Portugal. To do so, the study was based on a theoretical framework that covers the modernization of public administration to performance management, passing on people management. The work consisted of qualitative-descriptive research in which 16 semi-structured interviews were applied in the countries of study and documents and legislation were used referring to the subject. Performance management, as well as other people management subsystems, is criticized for using private sector management tools, based on a results-driven logic. From this point of view, it is understood that certain practices of the private sector, regarding the measurement of performance, can not be simply inserted in the scenario of the public administration. Beyond this criticism, performance management can contribute to the achievement of the strategic objectives of the countries and its focus is upward, a trend that can be verified through the manuals produced; by the interest of consultants and professional organizations, both public and private; and OECD (Organization for Economic Cooperation and Development) evaluations. In Portugal, public administration reform was implemented during the Constitutional Government (2005-2009) and had as its objective the restructuring of human resources management, with an emphasis on its integration with budget management, which is an inclination of the OECD, while in Chile HRM (Human Resource Management) practices are directed to ministries to a lesser extent than the OECD average. The central human resources management sector, for the most part, coordinates policy but is also responsible for other issues, including payment and classification systems. Chile makes less use of strategic Human Resource Management practices than the average of OECD countries, and its prominence lies in the decentralization of public bodies, which may grant autonomy, but fragments the implementation of policies and practices in that country since they are not adopted by all organs. Through the analysis, it was possible to identify that Chile and Portugal have practices and personnel management policies that make reference to performance management, which is similar to other OECD countries. The study countries also have limitations to implement performance management and the results indicate that there are still processes to be perfected, such as performance appraisal and compensation.

Keywords: management of people in the public sector, modernization of public administration, performance management in the public sector, HRM, OECD

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3584 Comparison of Soils of Hungarian Dry and Humid Oak Forests Based on Changes in Nutrient Content

Authors: István Fekete, Imre Berki, Áron Béni, Katalin Juhos, Marianna Makádi, Zsolt Kotroczó

Abstract:

The average annual precipitation significantly influences the moisture content of the soils and, through this, the decomposition of the organic substances in the soils, the leaching of nutrients from the soils, and the pH of the soils. Climate change, together with the lengthening of the vegetation period and the increasing CO₂ level, can increase the amount of biomass that is formed. Degradation processes, which accelerate as the temperature increases and slow down due to the drying climate, and the change in the degree of leaching can cancel out or strengthen each other's effects. In the course of our research, we looked for oak forests with climate-zonal soils where the geological, geographical and ecological background conditions are as similar as possible, apart from the different annual precipitation averages and the differences that can arise from them. We examined 5 dry and 5 humid Hungarian oak soils. Climate change affects the soils of drier and wetter forests differently. The aim of our research was to compare the content of carbon, nitrogen and some other nutrients, as well as the pH of the soils of humid and dry forests. Showing the effects of the drier climate on the tested soil parameters. In the case of the examined forest soils, we found a significant difference between the soils of dry and humid forests: in the case of the annual average precipitation values (p≥ 0.0001, for dry forest soils: 564±5.2 mm; for humid forest soils: 716±3.8 mm) for pH (p= 0.0004, for dry forest soils: 5.49±0.16; for wet forest soils: 5.36±0.21); for C content (p= 0.0054, for dry forest soils: 6.92%±0.59; for humid forest soils 3.09%±0.24), for N content (p= 0.0022, dry forest in the case of soils: 0.44%±0.047; in the case of humid forest soils: 0.23%±0.013), for the K content (p=0.0017, in the case of dry forest soils: 5684±732 (mg/kg); in the case of humid forest soils 2169±196 (mg/kg)), for the Ca content (p= 0.0096, for dry forest soils: 8207±2118 (mg/kg); for wet forest soils 957±320 (mg/kg)). No significant difference was found in the case of Mg. In a wetter environment, especially if the moisture content of the soil is also optimal for the decomposing organisms during the growing season, the decomposition of organic residues accelerates, and the processes of leaching from the soil are also intensified. The different intensity of the leaching processes is also well reflected in the quantitative differences of Ca and K, and in connection with these, it is also reflected in the difference in pH values. The differences in the C and N content can be explained by differences in the intensity of the decomposition processes. In addition to warming, drying is expected in a significant part of Hungary due to climate change. Thus, the comparison of the soils of dry and humid forests allows us to predict the subsequent changes in the case of the examined parameters.

Keywords: soil nutrients, precipitation difference, climate change, organic matter decomposition, leaching

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3583 Assessment of Seeding and Weeding Field Robot Performance

Authors: Victor Bloch, Eerikki Kaila, Reetta Palva

Abstract:

Field robots are an important tool for enhancing efficiency and decreasing the climatic impact of food production. There exists a number of commercial field robots; however, since this technology is still new, the robot advantages and limitations, as well as methods for optimal using of robots, are still unclear. In this study, the performance of a commercial field robot for seeding and weeding was assessed. A research 2-ha sugar beet field with 0.5m row width was used for testing, which included robotic sowing of sugar beet and weeding five times during the first two months of the growing. About three and five percent of the field were used as untreated and chemically weeded control areas, respectively. The plant detection was based on the exact plant location without image processing. The robot was equipped with six seeding and weeding tools, including passive between-rows harrow hoes and active hoes cutting inside rows between the plants, and it moved with a maximal speed of 0.9 km/h. The robot's performance was assessed by image processing. The field images were collected by an action camera with a height of 2 m and a resolution 27M pixels installed on the robot and by a drone with a 16M pixel camera flying at 4 m height. To detect plants and weeds, the YOLO model was trained with transfer learning from two available datasets. A preliminary analysis of the entire field showed that in the areas treated by the robot, the weed average density varied across the field from 6.8 to 9.1 weeds/m² (compared with 0.8 in the chemically treated area and 24.3 in the untreated area), the weed average density inside rows was 2.0-2.9 weeds / m (compared with 0 on the chemically treated area), and the emergence rate was 90-95%. The information about the robot's performance has high importance for the application of robotics for field tasks. With the help of the developed method, the performance can be assessed several times during the growth according to the robotic weeding frequency. When it’s used by farmers, they can know the field condition and efficiency of the robotic treatment all over the field. Farmers and researchers could develop optimal strategies for using the robot, such as seeding and weeding timing, robot settings, and plant and field parameters and geometry. The robot producers can have quantitative information from an actual working environment and improve the robots accordingly.

Keywords: agricultural robot, field robot, plant detection, robot performance

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3582 Reducing Accidents Using Text Stops

Authors: Benish Chaudhry

Abstract:

Most of the accidents these days are occurring because of the ‘text-and-drive’ concept. If we look at the structure of cities in UAE, there are great distances, because of which it is impossible to drive without using or merely checking the cellphone. Moreover, if we look at the road structure, it is almost impossible to stop at a point and text. With the introduction of TEXT STOPs, drivers will be able to stop different stops for a maximum of 1 and a half-minute in order to reply or write a message. They can be introduced at a distance of 10 minutes of driving on the average speed of the road, so the drivers can look forward to a stop and can reply to a text when needed. A user survey indicates that drivers are willing to NOT text-and-drive if they have such a facility available.

Keywords: transport, accidents, urban planning, road planning

Procedia PDF Downloads 385
3581 Acoustic Emission Monitoring of Surface Roughness in Ultra High Precision Grinding of Borosilicate-Crown Glass

Authors: Goodness Onwuka, Khaled Abou-El-Hossein

Abstract:

The increase in the demand for precision optics, coupled with the absence of much research output in the ultra high precision grinding of precision optics as compared to the ultrahigh precision diamond turning of optical metals has fostered the need for more research in the ultra high precision grinding of an optical lens. Furthermore, the increase in the stringent demands for nanometric surface finishes through lapping, polishing and grinding processes necessary for the use of borosilicate-crown glass in the automotive and optics industries has created the demand to effectively monitor the surface roughness during the production process. Acoustic emission phenomenon has been proven as useful monitoring technique in several manufacturing processes ranging from monitoring of bearing production to tool wear estimation. This paper introduces a rare and unique approach with the application of acoustic emission technique to monitor the surface roughness of borosilicate-crown glass during an ultra high precision grinding process. This research was carried out on a 4-axes Nanoform 250 ultrahigh precision lathe machine using an ultra high precision grinding spindle to machine the flat surface of the borosilicate-crown glass with the tip of the grinding wheel. A careful selection of parameters and design of experiment was implemented using Box-Behnken method to vary the wheel speed, feed rate and depth of cut at three levels with a 3-center point design. Furthermore, the average surface roughness was measured using Taylor Hobson PGI Dimension XL optical profilometer, and an acoustic emission data acquisition device from National Instruments was utilized to acquire the signals while the data acquisition codes were designed with National Instrument LabVIEW software for acquisition at a sampling rate of 2 million samples per second. The results show that the raw and root mean square amplitude values of the acoustic signals increased with a corresponding increase in the measured average surface roughness values for the different parameter combinations. Therefore, this research concludes that acoustic emission monitoring technique is a potential technique for monitoring the surface roughness in the ultra high precision grinding of borosilicate-crown glass.

Keywords: acoustic emission, borosilicate-crown glass, surface roughness, ultra high precision grinding

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3580 Effect of Spirulina Supplementation on Growth Performance and Body Conformation of Two Omani Goat Breeds

Authors: Fahad Al Yahyaey, Ihab Shaat, Russell Bush

Abstract:

This study was conducted at the Livestock Research Centre, Ministry of Agriculture and Fisheries, Oman, on two local goat breeds (Jabbali and Sahrawi) due to their importance to Omani livestock production and food security. The Jabbali is characterized by increased growth rates and a higher twinning rate, while the Sahrawi has increased milk production. The aim of the study was to investigate the effect of Spirulina supplementation on live weight (BWT), average daily gain (ADG), and body conformation measurements; chest girth (CG), wither height (WH), body length (BL), and body condition score (BCS). Thirty-six males (approximately nine-months-old and 16.44 ± 0.33 kg average of initial body weight) were used across an eleven-week study from November–February 2019-2020. Each breed was divided into three groups (n = 6/group) and fed one of three rations: (1) concentrate mixture (Control) with crude protein 14% and energy 11.97% MJ/kg DM; (2) the same concentrate feed with the addition of 2 gm /capita daily Spirulina platensis (Treatment 1) and (3) the same concentrate feed with the addition of 4 gm /capita daily Spirulina platensis (Treatment 2). Analysis of weekly data collections for all traits indicated a significant effect of feeding Spirulina on all the studied traits except WH and BL. Analysis of variance for fixed effects in this study (damage and kid birth type i.e., single, twin or triple) were not significant for all studied traits. However, the breed effect was highly significant (P < 0.001) on BWT, ADG, BCS, and CG traits. On the other hand, when the analysis was done for the treatment effect within breeds for ADG, the Sahrawi breed had a significant effect (P < 0.05) at 56.52, 85.51, and 85.50 g/day for control, treatment 1 and treatment 2, respectively. This is a 51% difference between the control and treatment 1 (2 gm /capita). Whereas for the Jabbali breed, the treatment effect was not significant for ADG (P =0.55), and the actual ADG was 104.59, 118.84, and 114.25 g/day for control, treatment 1, and treatment 2, respectively, providing a 14% difference between the control group and the treated group (4 gm /capita). These findings indicate using Spirulina supplementation in Omani goat diets is recommended at 2 gm per capita as there was no benefit in feeding at 4 gm per capita for either breed. Farmers feeding Spirulina supplementation to kids after weaning at six-months could increase their herd performance and growth rate and facilitate buck selection at an earlier age.

Keywords: body conformation, goats, live weight, spirulina

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3579 Exploration of Classic Models of Precipitation in Iran: A Case Study of Sistan and Baluchestan Province

Authors: Mohammad Borhani, Ahmad Jamshidzaei, Mehdi Koohsari

Abstract:

The study of climate has captivated human interest throughout history. In response to this fascination, individuals historically organized their daily activities in alignment with prevailing climatic conditions and seasonal variations. Understanding the elements and specific climatic parameters of each region, such as precipitation, which directly impacts human life, is essential because, in recent years, there has been a significant increase in heavy rainfall in various parts of the world attributed to the effects of climate change. Climate prediction models suggest a future scenario characterized by an increase in severe precipitation events and related floods on a global scale. This is a result of human-induced greenhouse gas emissions causing changes in the natural precipitation patterns. The Intergovernmental Panel on Climate Change reported global warming in 2001. The average global temperature has shown an increasing trend since 1861. In the 20th century, this increase has been between (0/2 ± 0/6) °C. The present study focused on examining the trend of monthly, seasonal, and annual precipitation in Sistan and Baluchestan provinces. The study employed data obtained from 13 precipitation measurement stations managed by the Iran Water Resources Management Company, encompassing daily precipitation records spanning the period from 1997 to 2016. The results indicated that the total monthly precipitation at the studied stations in Sistan and Baluchestan province follows a sinusoidal trend. The highest intense precipitation was observed in January, February, and March, while the lowest occurred in September, October, and then November. The investigation of the trend of seasonal precipitation in this province showed that precipitation follows an upward trend in the autumn season, reaching its peak in winter, and then shows a decreasing trend in spring and summer. Also, the examination of average precipitation indicated that the highest yearly precipitation occurred in 1997 and then in 2004, while the lowest annual precipitation took place between 1999 and 2001. The analysis of the annual precipitation trend demonstrates a decrease in precipitation from 1997 to 2016 in Sistan and Baluchestan province.

Keywords: climate change, extreme precipitation, greenhouse gas, trend analysis

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3578 Steady State Analysis of Distribution System with Wind Generation Uncertainity

Authors: Zakir Husain, Neem Sagar, Neeraj Gupta

Abstract:

Due to the increased penetration of renewable energy resources in the distribution system, the system is no longer passive in nature. In this paper, a steady state analysis of the distribution system has been done with the inclusion of wind generation. The modeling of wind turbine generator system and wind generator has been made to obtain the average active and the reactive power injection into the system. The study has been conducted on a IEEE-33 bus system with two wind generators. The present research work is useful not only to utilities but also to customers.

Keywords: distributed generation, distribution network, radial network, wind turbine generating system

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3577 Mapping of Urban Micro-Climate in Lyon (France) by Integrating Complementary Predictors at Different Scales into Multiple Linear Regression Models

Authors: Lucille Alonso, Florent Renard

Abstract:

The characterizations of urban heat island (UHI) and their interactions with climate change and urban climates are the main research and public health issue, due to the increasing urbanization of the population. These solutions require a better knowledge of the UHI and micro-climate in urban areas, by combining measurements and modelling. This study is part of this topic by evaluating microclimatic conditions in dense urban areas in the Lyon Metropolitan Area (France) using a combination of data traditionally used such as topography, but also from LiDAR (Light Detection And Ranging) data, Landsat 8 satellite observation and Sentinel and ground measurements by bike. These bicycle-dependent weather data collections are used to build the database of the variable to be modelled, the air temperature, over Lyon’s hyper-center. This study aims to model the air temperature, measured during 6 mobile campaigns in Lyon in clear weather, using multiple linear regressions based on 33 explanatory variables. They are of various categories such as meteorological parameters from remote sensing, topographic variables, vegetation indices, the presence of water, humidity, bare soil, buildings, radiation, urban morphology or proximity and density to various land uses (water surfaces, vegetation, bare soil, etc.). The acquisition sources are multiple and come from the Landsat 8 and Sentinel satellites, LiDAR points, and cartographic products downloaded from an open data platform in Greater Lyon. Regarding the presence of low, medium, and high vegetation, the presence of buildings and ground, several buffers close to these factors were tested (5, 10, 20, 25, 50, 100, 200 and 500m). The buffers with the best linear correlations with air temperature for ground are 5m around the measurement points, for low and medium vegetation, and for building 50m and for high vegetation is 100m. The explanatory model of the dependent variable is obtained by multiple linear regression of the remaining explanatory variables (Pearson correlation matrix with a |r| < 0.7 and VIF with < 5) by integrating a stepwise sorting algorithm. Moreover, holdout cross-validation is performed, due to its ability to detect over-fitting of multiple regression, although multiple regression provides internal validation and randomization (80% training, 20% testing). Multiple linear regression explained, on average, 72% of the variance for the study days, with an average RMSE of only 0.20°C. The impact on the model of surface temperature in the estimation of air temperature is the most important variable. Other variables are recurrent such as distance to subway stations, distance to water areas, NDVI, digital elevation model, sky view factor, average vegetation density, or building density. Changing urban morphology influences the city's thermal patterns. The thermal atmosphere in dense urban areas can only be analysed on a microscale to be able to consider the local impact of trees, streets, and buildings. There is currently no network of fixed weather stations sufficiently deployed in central Lyon and most major urban areas. Therefore, it is necessary to use mobile measurements, followed by modelling to characterize the city's multiple thermal environments.

Keywords: air temperature, LIDAR, multiple linear regression, surface temperature, urban heat island

Procedia PDF Downloads 127
3576 Optimal Number and Placement of Vertical Links in 3D Network-On-Chip

Authors: Nesrine Toubaline, Djamel Bennouar, Ali Mahdoum

Abstract:

3D technology can lead to a significant reduction in power and average hop-count in Networks on Chip (NoCs). It offers short and fast vertical links which copes with the long wire problem in 2D NoCs. This work proposes heuristic-based method to optimize number and placement of vertical links to achieve specified performance goals. Experiments show that significant improvement can be achieved by using a specific number of vertical interconnect.

Keywords: interconnect optimization, monolithic inter-tier vias, network on chip, system on chip, through silicon vias, three dimensional integration circuits

Procedia PDF Downloads 294
3575 Geochemical Characteristics and Chemical Toxicity: Appraisal of Groundwater Uranium With Other Geogenic Contaminants in Various Districts of Punjab, India

Authors: Tanu Sharma, Bikramjit Singh Bajwa, Inderpreet Kaur

Abstract:

Monitoring of groundwater in Tarn-Taran, Bathinda, Faridkot and Mansa districts of Punjab state, India is essential where this freshwater resource is being over-exploited causing quality deterioration, groundwater depletion and posing serious threats to residents. The present integrated study was done to appraise quality and suitability of groundwater for drinking/irrigation purposes, hydro-geochemical characteristics, source identification and associated health risks. In the present study, groundwater of various districts of Punjab state was found to be heavily contaminated with As followed by U, thus posing high cancerous risks to local residents via ingestion, along with minor contamination of Fe, Mn, Pb and F−. Most health concerns in the study region were due to the elevated concentrations of arsenic in groundwater with average values of 130 µg L-1, 176 µg L-1, 272 µg L-1 and 651 µg L-1 in Tarn-Taran, Bathinda, Faridkot and Mansa districts, respectively, which is quite high as compared to the safe limit as recommended by BIS i.e. 10 µg L-1. In Tarn-Taran, Bathinda, Faridkot and Mansa districts, average uranium contents were found to be 37 µg L-1, 88 µg L-1, 61 µg L-1 and 104 µg L-1, with 51 %, 74 %, 61 % and 71 % samples, respectively, being above the WHO limit of 30 µg L-1 in groundwater. Further, the quality indices showed that groundwater of study region is suited for irrigation but not appropriate for drinking purposes. Hydro-geochemical studies revealed that most of the collected groundwater samples belonged to Ca2+ - Mg2+ - HCO3- type showing dominance of MgCO3 type which indicates the presence of temporary hardness in groundwater. Rock-water reactions and reverse ion exchange were the predominant factors for controlling hydro-geochemistry in the study region. Dissolution of silicate minerals caused the dominance of Na+ ions in the aquifers of study region. Multivariate statistics revealed that along with geogenic sources, contribution of anthropogenic activities such as injudicious application of agrochemicals and domestic waste discharge was also very significant. The results obtained abolished the myth that uranium is only root cause for large number of cancer patients in study region as arsenic and mercury were also present in groundwater at levels that were of health concern to groundwater.

Keywords: uranium, trace elements, multivariate data analysis, risk assessment

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3574 A Ground Observation Based Climatology of Winter Fog: Study over the Indo-Gangetic Plains, India

Authors: Sanjay Kumar Srivastava, Anu Rani Sharma, Kamna Sachdeva

Abstract:

Every year, fog formation over the Indo-Gangetic Plains (IGPs) of Indian region during the winter months of December and January is believed to create numerous hazards, inconvenience, and economic loss to the inhabitants of this densely populated region of Indian subcontinent. The aim of the paper is to analyze the spatial and temporal variability of winter fog over IGPs. Long term ground observations of visibility and other meteorological parameters (1971-2010) have been analyzed to understand the formation of fog phenomena and its relevance during the peak winter months of January and December over IGP of India. In order to examine the temporal variability, time series and trend analysis were carried out by using the Mann-Kendall Statistical test. Trend analysis performed by using the Mann-Kendall test, accepts the alternate hypothesis with 95% confidence level indicating that there exists a trend. Kendall tau’s statistics showed that there exists a positive correlation between time series and fog frequency. Further, the Theil and Sen’s median slope estimate showed that the magnitude of trend is positive. Magnitude is higher during January compared to December for the entire IGP except in December when it is high over the western IGP. Decade wise time series analysis revealed that there has been continuous increase in fog days. The net overall increase of 99 % was observed over IGP in last four decades. Diurnal variability and average daily persistence were computed by using descriptive statistical techniques. Geo-statistical analysis of fog was carried out to understand the spatial variability of fog. Geo-statistical analysis of fog revealed that IGP is a high fog prone zone with fog occurrence frequency of more than 66% days during the study period. Diurnal variability indicates the peak occurrence of fog is between 06:00 and 10:00 local time and average daily fog persistence extends to 5 to 7 hours during the peak winter season. The results would offer a new perspective to take proactive measures in reducing the irreparable damage that could be caused due to changing trends of fog.

Keywords: fog, climatology, Mann-Kendall test, trend analysis, spatial variability, temporal variability, visibility

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3573 Dielectric Properties of La2MoO6 Ceramics at Microwave Frequency

Authors: Yih-Chien Chen, Yu-Cheng You

Abstract:

The microwave dielectric properties of La2MoO6 ceramics were investigated with a view to their application in mobile communication. La2MoO6 ceramics were prepared by the conventional solid-state method with various sintering conditions. The X-ray diffraction peaks of La2MoO6 ceramic did not vary significantly with sintering conditions. The average grain size of La2MoO6 ceramics increased as the temperature and time of sintering increased. A maximum density of 5.67 g/cm3, a dielectric constants (εr) of 14.1, a quality factor (Q×f) of 68,000 GHz, and a temperature coefficient of resonant frequency (τf) of -56 ppm/℃ were obtained when La2MoO6 ceramics that were sintered at 1300 ℃ for 4h.

Keywords: ceramics, sintering, microwave dielectric properties, La2MoO6

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3572 Emerging Issues for Global Impact of Foreign Institutional Investors (FII) on Indian Economy

Authors: Kamlesh Shashikant Dave

Abstract:

The global financial crisis is rooted in the sub-prime crisis in U.S.A. During the boom years, mortgage brokers attracted by the big commission, encouraged buyers with poor credit to accept housing mortgages with little or no down payment and without credit check. A combination of low interest rates and large inflow of foreign funds during the booming years helped the banks to create easy credit conditions for many years. Banks lent money on the assumptions that housing price would continue to rise. Also the real estate bubble encouraged the demand for houses as financial assets .Banks and financial institutions later repackaged these debts with other high risk debts and sold them to worldwide investors creating financial instruments called collateral debt obligations (CDOs). With the rise in interest rate, mortgage payments rose and defaults among the subprime category of borrowers increased accordingly. Through the securitization of mortgage payments, a recession developed in the housing sector and consequently it was transmitted to the entire US economy and rest of the world. The financial credit crisis has moved the US and the global economy into recession. Indian economy has also affected by the spill over effects of the global financial crisis. Great saving habit among people, strong fundamentals, strong conservative and regulatory regime have saved Indian economy from going out of gear, though significant parts of the economy have slowed down. Industrial activity, particularly in the manufacturing and infrastructure sectors decelerated. The service sector too, slow in construction, transport, trade, communication, hotels and restaurants sub sectors. The financial crisis has some adverse impact on the IT sector. Exports had declined in absolute terms in October. Higher inputs costs and dampened demand have dented corporate margins while the uncertainty surrounding the crisis has affected business confidence. To summarize, reckless subprime lending, loose monetary policy of US, expansion of financial derivatives beyond acceptable norms and greed of Wall Street has led to this exceptional global financial and economic crisis. Thus, the global credit crisis of 2008 highlights the need to redesign both the global and domestic financial regulatory systems not only to properly address systematic risk but also to support its proper functioning (i.e financial stability).Such design requires: 1) Well managed financial institutions with effective corporate governance and risk management system 2) Disclosure requirements sufficient to support market discipline. 3)Proper mechanisms for resolving problem institution and 4) Mechanisms to protect financial services consumers in the event of financial institutions failure.

Keywords: FIIs, BSE, sensex, global impact

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3571 Evaluation of the Surveillance System for Rift Valley Fever in Ruminants in Mauritania, 2019

Authors: Mohamed El Kory Yacoub, Ahmed Bezeid El Mamy Beyatt, Djibril Barry, Yanogo Pauline, Nicolas Meda

Abstract:

Introduction: Rift Valley Fever is a zoonotic arbovirosis that severely affects ruminants, as well as humans. It causes abortions in pregnant females and deaths in young animals. The disease occurs during heavy rains followed by large numbers of mosquito vectors. The objective of this work is to evaluate the surveillance system for Rift Valley Fever. Methods: We conducted an evaluation of the Rift Valley Fiver surveillance system. Data were collected from the analysis of the national database of the Mauritanian Network of Animal Disease Epidemiological Surveillance at the Ministry of Rural Development, of RVF cases notified from the whole national territory, of questionnaires and interviews with all persons involved in RVF surveillance at the central level. The quality of the system was assessed by analyzing the quantitative attributes defined by the Centers for Disease Control and Prevention. Results: In 2019, 443 cases of RVF were notified by the surveillance system, of which 36 were positive. Among the notified cases of Rift Valley Fever, the 0- to the 3-year-old age group of small ruminants was the most represented with 49.21% of cases, followed by 33.33%, which was recorded in large ruminants in the 0 to 7-year-old age group, 11.11% of cases were older than seven years. The completeness of the data varied between 14.2% (age) and 100% (species). Most positive cases were recorded between October and November 2019 in seven different regions. Attribute analysis showed that 87% of the respondents were able to use the case definition well, and 78.8% said they were familiar with the reporting and feedback loop of the Rift Valley Fever data. 90.3% of the respondents found it easy, while 95% of them responded that it was easy for them to transmit their data to the next level. Conclusions: The epidemiological surveillance system for Rift Valley Fever in Mauritania is simple and representative. However, data quality, stability, and responsiveness are average, as the diagnosis of the disease requires laboratory confirmation and the average delay for this confirmation is long (13 days). Consequently, the lack of completeness of the recorded data and of description of cases in terms of time-place-animal, associated with the delay between the stages of the surveillance system can make prevention, early detection of epidemics, and the initiation of measures for an adequate response difficult.

Keywords: evaluation, epidemiological surveillance system, rift valley fever, mauritania, ruminants

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3570 Nutritional Value Determination of Different Varieties of Oats and Barley Using Near-Infrared Spectroscopy Method for the Horses Nutrition

Authors: V. Viliene, V. Sasyte, A. Raceviciute-Stupeliene, R. Gruzauskas

Abstract:

In horse nutrition, the most suitable cereal for their rations composition could be defined as oats and barley. Oats have high nutritive value because it provides more protein, fiber, iron and zinc than other whole grains, has good taste, and an activity of stimulating metabolic changes in the body. Another cereal – barley is very similar to oats as a feed except for some characteristics that affect how it is used; however, barley is lower in fiber than oats and is classified as a "heavy" feed. The value of oats and barley grain, first of all is dependent on its composition. Near-infrared spectroscopy (NIRS) has long been considered and used as a significant method in component and quality analysis and as an emerging technology for authenticity applications for cereal quality control. This paper presents the chemical and amino acid composition of different varieties of barley and oats, also digestible energy of different cereals for horses. Ten different spring barley (n = 5) and oats (n = 5) varieties, grown in one location in Lithuania, were assayed for their chemical composition (dry matter, crude protein, crude fat, crude ash, crude fiber, starch) and amino acids content, digestible amino acids and amino acids digestibility. Also, the grains digestible energy for horses was calculated. The oats and barley samples reflectance spectra were measured by means of NIRS using Foss-Tecator DS2500 equipment. The chemical components: fat, crude protein, starch and fiber differed statistically (P<0.05) between the oats and barley varieties. The highest total amino acid content between oats was determined in variety Flamingsprofi (4.56 g/kg) and the lowest – variety Circle (3.57 g/kg), and between barley - respectively in varieties Publican (3.50 g/kg) and Sebastian (3.11 g/kg). The different varieties of oats digestible amino acid content varied from 3.11 g/kg to 4.07 g/kg; barley different varieties varied from 2.59 g/kg to 2.94 g/kg. The average amino acids digestibility of oats varied from 74.4% (Liz) to 95.6% (Fen) and in barley - from 75.8 % (Tre) to 89.6% (Fen). The amount of digestible energy in the analyzed varieties of oats and barley was an average compound 13.74 MJ/kg DM and 14.85 MJ/kg DM, respectively. An analysis of the results showed that different varieties of oats compared with barley are preferable for horse nutrition according to the crude fat, crude fiber, ash and separate amino acids content, but the analyzed barley varieties dominated the higher amounts of crude protein, the digestible Liz amount and higher DE content, and thus, could be recommended for making feed formulation for horses combining oats and barley, taking into account the chemical composition of using cereal varieties.

Keywords: barley, digestive energy, horses, nutritional value, oats

Procedia PDF Downloads 197
3569 Effect of Plant Growth Promoting Rhizobacteria on the Germination and Early Growth of Onion (Allium cepa)

Authors: Dragana R. Stamenov, Simonida S. Djuric, Timea Hajnal Jafari

Abstract:

Plant growth promoting rhizobacteria (PGPR) are a heterogeneous group of bacteria that can be found in the rhizosphere, at root surfaces and in association with roots, enhancing the growth of the plant either directly and/or indirectly. Increased crop productivity associated with the presence of PGPR has been observed in a broad range of plant species, such as raspberry, chickpeas, legumes, cucumber, eggplant, pea, pepper, radish, tobacco, tomato, lettuce, carrot, corn, cotton, millet, bean, cocoa, etc. However, until now there has not been much research about influences of the PGPR on the growth and yield of onion. Onion (Allium cepa L.), of the Liliaceae family, is a species of great economic importance, widely cultivated all over the world. The aim of this research was to examine the influence of plant growth promoting bacteria Pseudomonas sp. Dragana, Pseudomonas sp. Kiš, Bacillus subtillis and Azotobacter sp. on the seed germination and early growth of onion (Allium cepa). PGPR Azotobacter sp., Bacillus subtilis, Pseudomonas sp. Dragana, Pseudomonas sp. Kiš, from the collection of the Faculty of Agriculture, Novi Sad, Serbia, were used as inoculants. The number of cells in 1 ml of the inoculum was 10⁸ CFU/ml. The control variant was not inoculated. The effect of PGPR on seed germination and hypocotyls length of Allium cepa was evaluated in controlled conditions, on filter paper in the dark at 22°C, while effect on the plant length and mass in semicontrol conditions, in 10 l volume vegetative pots. Seed treated with fungicide and untreated seed were used. After seven days the percentage of germination was determined. After seven and fourteen days hypocotil length was measured. Fourteen days after germination, length and mass of plants were measured. Application of Pseudomonas sp. Dragana and Kiš and Bacillus subtillis had a negative effect on onion seed germination, while the use of Azotobacter sp. gave positive results. On average, application of all investigated inoculants had a positive effect on the measured parameters of plant growth. Azotobacter sp. had the greatest effect on the hypocotyls length, length and mass of the plant. In average, better results were achieved with untreated seeds in compare with treated. Results of this study have shown that PGPR can be used in the production of onion.

Keywords: germination, length, mass, microorganisms, onion

Procedia PDF Downloads 221
3568 Competence of the Health Workers in Diagnosing and Managing Complicated Pregnancies: A Clinical Vignette Based Assessment in District and Sub-District Hospitals in Bangladesh

Authors: Abdullah Nurus Salam Khan, Farhana Karim, Mohiuddin Ahsanul Kabir Chowdhury, S. Masum Billah, Nabila Zaka, Alexander Manu, Shams El Arifeen

Abstract:

Globally, pre-eclampsia (PE) and ante-partum haemorrhage (APH) are two major causes of maternal mortality. Prompt identification and management of these conditions depend on competency of the birth attendants. Since these conditions are infrequent to be observed, clinical vignette based assessment could identify the extent of health worker’s competence in managing emergency obstetric care (EmOC). During June-August 2016, competence of 39 medical officers (MO) and 95 nurses working in obstetric ward of 15 government health facilities (3 district hospital, 12 sub-district hospital) was measured using clinical vignettes on PE and APH. The vignettes resulted in three outcome measures: total vignette scores, scores for diagnosis component, and scores for management component. T-test was conducted to compare mean vignette scores and linear regression was conducted to measure the strength and association of vignette scores with different cadres of health workers, facility’s readiness for EmOC and average annual utilization of normal deliveries after adjusting for type of health facility, health workers’ work experience, training status on managing maternal complication. For each of the seven component of EmOC items (administration of injectable antibiotics, oxytocic and anticonvulsant; manual removal of retained placenta, retained products of conception; blood transfusion and caesarean delivery), if any was practised in the facility within last 6 months, a point was added and cumulative EmOC readiness score (range: 0-7) was generated for each facility. The yearly utilization of delivery cases were identified by taking the average of all normal deliveries conducted during three years (2013-2015) preceding the survey. About 31% of MO and all nurses were female. Mean ( ± sd) age of the nurses were higher than the MO (40.0 ± 6.9 vs. 32.2 ± 6.1 years) and also longer mean( ± sd) working experience (8.9 ± 7.9 vs. 1.9 ± 3.9 years). About 80% health workers received any training on managing maternal complication, however, only 7% received any refresher’s training within last 12 months. The overall vignette score was 8.8 (range: 0-19), which was significantly higher among MO than nurses (10.7 vs. 8.1, p < 0.001) and the score was not associated with health facility types, training status and years of experience of the providers. Vignette score for management component (range: 0-9) increased with higher annual average number of deliveries in their respective working facility (adjusted β-coefficient 0.16, CI 0.03-0.28, p=0.01) and increased with each unit increase in EmOC readiness score (adjusted β-coefficient 0.44, CI 0.04-0.8, p=0.03). The diagnosis component of vignette score was not associated with any of the factors except it was higher among the MO than the nurses (adjusted β-coefficient 1.2, CI 0.13-2.18, p=0.03). Lack of competence in diagnosing and managing obstetric complication by the nurses than the MO is of concern especially when majority of normal deliveries are conducted by the nurses. Better EmOC preparedness of the facility and higher utilization of normal deliveries resulted in higher vignette score for the management component; implying the impact of experiential learning through higher case management. Focus should be given on improving the facility readiness for EmOC and providing the health workers periodic refresher’s training to make them more competent in managing obstetric cases.

Keywords: Bangladesh, emergency obstetric care, clinical vignette, competence of health workers

Procedia PDF Downloads 180
3567 Change of Epidemiological Characteristics and Disease Burden of Varicella Due to Implementation of Mass Immunization Program in Taiwan from 2000 to 2012

Authors: En-Tzu Wang, Ting-Ann Wang, Yi-Hui Shen, Yu-Min Chou, Chi-Tai Fang, Chin-Hui Yang

Abstract:

Background and purpose: A mass varicella immunization program was established to provide free 1-dose vaccination for all 1-year-old children throughout Taiwan since 2004. The epidemiological characteristics and disease burden of varicella from 2000 to 2012 was investigated and the results will be essential to refine the national immunization policy. Method: We included patients (n = 17,838–164,245) with ICD-9-CM codes 052 (chickenpox) from the 2000 to 2012 National Health Insurance Database. The age, period, and cohort-specific incidence of varicella were calculated. The hospital admission rate, medical costs and indirect costs from the societal perspective of varicella including travel costs to the medical facility, registration fee, productivity losses of the patients and caregivers were also estimated. Result: There were 979,252 patients for medical treatment due to varicella from 2000 to 2012 in Taiwan. The implementation of a routine childhood varicella vaccination program has resulted in 87% decline in morbidity (881.49 to 115.17 per 100,000). The average age of patients increased from 7.9 years to 16.3 years. The overall varicella-related hospital admission rate was 15.5 per 1000 patients, and peaked in the groups of infants younger than 1 year, adults aged from 20 to 39 years and elders over 70 years. Among patients admitted to hospital, 33.5% of them had one or more complications. Patients with underlying diseases had higher admission rate (241.6 per 1,000) and longer duration of hospital stay (6.61 days vs. 4.76 days). The annual varicella-related medical expense declined after 2002 and the proportion of medical costs for admission has increased to 42%. The annual indirect costs from the societal perspective of varicella were 5.29 to 9.63 times higher than varicella-related medical costs. Every one dollar invested in the varicella immunization program, 2.97 dollars of medical and social costs were saved on average. Conclusion: The dramatic decline in morbidity, hospitalization, medical and social costs of varicella can be directly attributed to the implementation of the mass immunization program. Two-dose vaccination is recommended for both children with underlying diseases and susceptible adults to prevent serious complications and hospitalizations.

Keywords: disease burden, epidemiology, medical and social costs, varicella, varicella vaccine

Procedia PDF Downloads 394
3566 Blister Formation Mechanisms in Hot Rolling

Authors: Rebecca Dewfall, Mark Coleman, Vladimir Basabe

Abstract:

Oxide scale growth is an inevitable byproduct of the high temperature processing of steel. Blister is a phenomenon that occurs due to oxide growth, where high temperatures result in the swelling of surface scale, producing a bubble-like feature. Blisters can subsequently become embedded in the steel substrate during hot rolling in the finishing mill. This rolled in scale defect causes havoc within industry, not only with wear on machinery but loss of customer satisfaction, poor surface finish, loss of material, and profit. Even though blister is a highly prevalent issue, there is still much that is not known or understood. The classic iron oxidation system is a complex multiphase system formed of wustite, magnetite, and hematite, producing multi-layered scales. Each phase will have independent properties such as thermal coefficients, growth rate, and mechanical properties, etc. Furthermore, each additional alloying element will have different affinities for oxygen and different mobilities in the oxide phases so that oxide morphologies are specific to alloy chemistry. Therefore, blister regimes can be unique to each steel grade resulting in a diverse range of formation mechanisms. Laboratory conditions were selected to simulate industrial hot rolling with temperature ranges approximate to the formation of secondary and tertiary scales in the finishing mills. Samples with composition: 0.15Wt% C, 0.1Wt% Si, 0.86Wt% Mn, 0.036Wt% Al, and 0.028Wt% Cr, were oxidised in a thermo-gravimetric analyser (TGA), with an air velocity of 10litresmin-1, at temperaturesof 800°C, 850°C, 900°C, 1000°C, 1100°C, and 1200°C respectively. Samples were held at temperature in an argon atmosphere for 10minutes, then oxidised in air for 600s, 60s, 30s, 15s, and 4s, respectively. Oxide morphology and Blisters were characterised using EBSD, WDX, nanoindentation, FIB, and FEG-SEM imaging. Blister was found to have both a nucleation and growth process. During nucleation, the scale detaches from the substrate and blisters after a very short period, roughly 10s. The steel substrate is then exposed inside of the blister and further oxidised in the reducing atmosphere of the blister, however, the atmosphere within the blister is highly dependent upon the porosity of the blister crown. The blister crown was found to be consistently between 35-40um for all heating regimes, which supports the theory that the blister inflates, and the oxide then subsequently grows underneath. Upon heating, two modes of blistering were identified. In Mode 1 it was ascertained that the stresses produced by oxide growth will increase with increasing oxide thickness. Therefore, in Mode 1 the incubation time for blister formation is shortened by increasing temperature. In Mode 2 increase in temperature will result in oxide with a high ductility and high oxide porosity. The high oxide ductility and/or porosity accommodates for the intrinsic stresses from oxide growth. Thus Mode 2 is the inverse of Mode 1, and incubation time is increased with temperature. A new phenomenon was reported whereby blister formed exclusively through cooling at elevated temperatures above mode 2.

Keywords: FEG-SEM, nucleation, oxide morphology, surface defect

Procedia PDF Downloads 134
3565 Low Plastic Deformation Energy to Induce High Superficial Strain on AZ31 Magnesium Alloy Sheet

Authors: Emigdio Mendoza, Patricia Fernandez, Cristian Gomez

Abstract:

Magnesium alloys have generated great interest for several industrial applications because their high specific strength and low density make them a very attractive alternative for the manufacture of various components; however, these alloys present a limitation with their hexagonal crystal structure that limits the deformation mechanisms at room temperature likewise the molding components alternatives, it is for this reason that severe plastic deformation processes have taken a huge relevance recently because these, allow high deformation rates to be applied that induce microstructural changes where the deficiency in the sliding systems is compensated with crystallographic grains reorientations or crystal twinning. The present study reports a statistical analysis of process temperature, number of passes and shear angle with respect to the shear stress in severe plastic deformation process denominated 'Equal Channel Angular Sheet Drawing (ECASD)' applied to the magnesium alloy AZ31B through Python Statsmodels libraries, additionally a Post-Hoc range test is performed using the Tukey statistical test. Statistical results show that each variable has a p-value lower than 0.05, which allows comparing the average values of shear stresses obtained, which are in the range of 7.37 MPa to 12.23 MPa, lower values in comparison to others severe plastic deformation processes reported in the literature, considering a value of 157.53 MPa as the average creep stress for AZ31B alloy. However, a higher stress level is required when the sheets are processed using a shear angle of 150°, due to a higher level of adjustment applied for the shear die of 150°. Temperature and shear passes are important variables as well, but there is no significant impact on the level of stress applied during the ECASD process. In the processing of AZ31B magnesium alloy sheets, ECASD technique is evidenced as a viable alternative in the modification of the elasto-plastic properties of this alloy, promoting the weakening of the basal texture, which means, a better response to deformation, whereby, during the manufacture of parts by drawing or stamping processes the formation of cracks on the surface can be reduced, presenting an adequate mechanical performance.

Keywords: plastic deformation, strain, sheet drawing, magnesium

Procedia PDF Downloads 106
3564 Discovering Event Outliers for Drug as Commercial Products

Authors: Arunas Burinskas, Aurelija Burinskiene

Abstract:

On average, ten percent of drugs - commercial products are not available in pharmacies due to shortage. The shortage event disbalance sales and requires a recovery period, which is too long. Therefore, one of the critical issues that pharmacies do not record potential sales transactions during shortage and recovery periods. The authors suggest estimating outliers during shortage and recovery periods. To shorten the recovery period, the authors suggest using average sales per sales day prediction, which helps to protect the data from being downwards or upwards. Authors use the outlier’s visualization method across different drugs and apply the Grubbs test for significance evaluation. The researched sample is 100 drugs in a one-month time frame. The authors detected that high demand variability products had outliers. Among analyzed drugs, which are commercial products i) High demand variability drugs have a one-week shortage period, and the probability of facing a shortage is equal to 69.23%. ii) Mid demand variability drugs have three days shortage period, and the likelihood to fall into deficit is equal to 34.62%. To avoid shortage events and minimize the recovery period, real data must be set up. Even though there are some outlier detection methods for drug data cleaning, they have not been used for the minimization of recovery period once a shortage has occurred. The authors use Grubbs’ test real-life data cleaning method for outliers’ adjustment. In the paper, the outliers’ adjustment method is applied with a confidence level of 99%. In practice, the Grubbs’ test was used to detect outliers for cancer drugs and reported positive results. The application of the Grubbs’ test is used to detect outliers which exceed boundaries of normal distribution. The result is a probability that indicates the core data of actual sales. The application of the outliers’ test method helps to represent the difference of the mean of the sample and the most extreme data considering the standard deviation. The test detects one outlier at a time with different probabilities from a data set with an assumed normal distribution. Based on approximation data, the authors constructed a framework for scaling potential sales and estimating outliers with Grubbs’ test method. The suggested framework is applicable during the shortage event and recovery periods. The proposed framework has practical value and could be used for the minimization of the recovery period required after the shortage of event occurrence.

Keywords: drugs, Grubbs' test, outlier, shortage event

Procedia PDF Downloads 127
3563 Competitivity in Procurement Multi-Unit Discrete Clock Auctions: An Experimental Investigation

Authors: Despina Yiakoumi, Agathe Rouaix

Abstract:

Laboratory experiments were run to investigate the impact of different design characteristics of the auctions, which have been implemented to procure capacity in the UK’s reformed electricity markets. The experiment studies competition among bidders in procurement multi-unit discrete descending clock auctions under different feedback policies and pricing rules. Theory indicates that feedback policy in combination with the two common pricing rules; last-accepted bid (LAB) and first-rejected bid (FRB), could affect significantly the auction outcome. Two information feedback policies regarding the bidding prices of the participants are considered; with feedback and without feedback. With feedback, after each round participants are informed of the number of items still in the auction and without feedback, after each round participants have no information about the aggregate supply. Under LAB, winning bidders receive the amount of the highest successful bid and under the FRB the winning bidders receive the lowest unsuccessful bid. Based on the theoretical predictions of the alternative auction designs, it was decided to run three treatments. First treatment considers LAB with feedback; second treatment studies LAB without feedback; third treatment investigates FRB without feedback. Theoretical predictions of the game showed that under FRB, the alternative feedback policies are indifferent to the auction outcome. Preliminary results indicate that LAB with feedback and FRB without feedback achieve on average higher clearing prices in comparison to the LAB treatment without feedback. However, the clearing prices under LAB with feedback and FRB without feedback are on average lower compared to the theoretical predictions. Although under LAB without feedback theory predicts the clearing price will drop to the competitive equilibrium, experimental results indicate that participants could still engage in cooperative behavior and drive up the price of the auction. It is showed, both theoretically and experimentally, that the pricing rules and the feedback policy, affect the bidding competitiveness of the auction by providing opportunities to participants to engage in cooperative behavior and exercise market power. LAB without feedback seems to be less vulnerable to market power opportunities compared to the alternative auction designs. This could be an argument for the use of LAB pricing rule in combination with limited feedback in the UK capacity market in an attempt to improve affordability for consumers.

Keywords: descending clock auctions, experiments, feedback policy, market design, multi-unit auctions, pricing rules, procurement auctions

Procedia PDF Downloads 285
3562 Prevalence of Adverse Events in Children and Adolescents on Antiretroviral Therapy: Examining the Pediatric Cohort in the Eastern Cape

Authors: Shannon Glaspy, Gerald Boon, Jack Lambert

Abstract:

Studies on AE of highly active antiretroviral therapy (HAART) in children and adolescents are rare. The aim of this study is to observe the frequency of treatment limiting adverse drug reactions against years on ARVs and specific ARV regimen. Methods: A retrospective cohort study was conducted in East London, South Africa. All patient files in the pediatric (0 – 18 years) ARV cohort were examined, selecting only those patients started on HAART. ARV regimen changes explicitly due to AE, age on ARV treatment onset, age of AE onset, and gender were extrapolated. Eligible subjects were obtained from patient folders, anonymized and cross-referenced with data obtained from electronic records. A total of 1120 patients [592 male (52.9%) and 528 female (47.1%)] were charted by incidence and year. Additional information was extrapolated in cases where the patient experienced lipodystrophy and lipoatrophy to include the number of years on ARVs prior to the onset of the AE. Results: Of the 1120 HIV infected children of the hospital cohort, a total of 105 (9.37%) AE (53.3% male) observed were deemed eligible for the study due to completeness of medical history and agreement between electronic records and paper files. The AE cited were as follows: lipoatrophy 62 (5.53% of all subjects), lipodystrophy 27 (2.41%), neuropathy 9 (0.8%), anemia 2 (0.17%), Steven Johnsons Syndrome 1 (0.08%), elevated LFTs 1 (0.8%), breast hypertrophy (0.08%), gastritis 1 (0.08%) and rash 1 (0.08%). The most prevalence ARV regimens associated with the onset of the AE are: D4T/3TC/EFV 72 cases (64.86% of all AE), D4T/3TC/LOPr 24 cases (21.62%). Lipoatrophy and lipodystrophy combined represent 84.76% (89 cases) of all adverse events documented in this cohort. Within the 60 cases of lipoatrophy, the average number of years on ARVs associated with an AE is 3.54, with 14 cases experiencing an AE between 0-2 years of HAART. Within the 29 cases of lipodystrophy, the average number of years on ARVs associated with an AE is 3.89, with 4 cases experiencing an AE between 0-2 years on HAART. The regimen D4T/3TC/EFV is associated with 43 cases (71.66%) of lipoatrophy and 21 cases (72.41%) of lipodystrophy. D4T/3TC/LOPr is associated with 15 cases (25%) of lipoatrophy and 7 cases (24.14%) of lipodystrophy. The frequency of AE associated with ARV regimens could be misrepresented due to prevalence of different 1st line regimens which were not captured in this study, particularly with the systematic change of 1st line drugs from D4T to ABC in 2010. Conclusion: In this descriptive study we found a 9.37% prevalence of AE were significant enough to be treatment limiting among our cohort. Lipoatrophy accounted for 59.04% of all documented AE. Overall, D4T/3TC/EFV was associated with 64.86% of all AE, 71.66% of lipoatrophy cases and 72.41% of lipodystrophy cases.

Keywords: ARV, adverse events, HAART, pediatric

Procedia PDF Downloads 185
3561 Frequent-Flyer Program: The Connection between Commercial Partners and Spin-off

Authors: Changmin Jiang

Abstract:

In this paper, we build a theoretical model to investigate the relationship between two recent trends in airline frequent-flyer programs (FFPs): the adoption of the “coalition” business model with other commercial partners, and the separation from airlines’ operations. We show that commercial partners benefit from teaming up with FFP, while increasing the number of commercial partners will increase the total profit; it reduces the average profit of the parties involved. Furthermore, we show that the number of commercial partners of an FFP is negatively related with the benefit to keep the FFP in-house.

Keywords: frequent flyer program, coalition, commercial partners, spin-off

Procedia PDF Downloads 284
3560 Sol-Gel Derived ZnO Nanostructures: Optical Properties

Authors: Sheo K. Mishra, Rajneesh K. Srivastava, R. K. Shukla

Abstract:

In the present work, we report on the optical properties including UV-vis absorption and photoluminescence (PL) of ZnO nanostructures synthesized by sol-gel method. Structural and morphological investigations have been performed by X-ray diffraction method (XRD) and scanning electron microscopy (SEM). The XRD result confirms the formation of hexagonal wurtzite phase of ZnO nanostructures. The presence of various diffraction peaks suggests polycrystalline nature. The XRD pattern exhibits no additional peak due to by-products such as Zn(OH)2. The average crystallite size of prepared ZnO sample corresponding to the maximum intensity peaks is to be ~38.22 nm. The SEM micrograph shows different nanostructures of pure ZnO. Photoluminescence (PL) spectrum shows several emission peaks around 353 nm, 382 nm, 419 nm, 441 nm, 483 nm and 522 nm. The obtained results suggest that the prepared phosphors are quite suitable for optoelectronic applications.

Keywords: ZnO, sol-gel, XRD, PL

Procedia PDF Downloads 389
3559 Association between Noise Levels, Particulate Matter Concentrations and Traffic Intensities in a Near-Highway Urban Area

Authors: Mohammad Javad Afroughi, Vahid Hosseini, Jason S. Olfert

Abstract:

Both traffic-generated particles and noise have been associated with the development of cardiovascular diseases, especially in near-highway environments. Although noise and particulate matters (PM) have different mechanisms of dispersion, sharing the same emission source in urban areas (road traffics) can result in a similar degree of variability in their levels. This study investigated the temporal variation of and correlation between noise levels, PM concentrations and traffic intensities near a major highway in Tehran, Iran. Tehran particulate concentration is highly influenced by road traffic. Additionally, Tehran ultrafine particles (UFP, PM<0.1 µm) are mostly emitted from combustion processes of motor vehicles. This gives a high possibility of a strong association between traffic-related noise and UFP in near-highway environments of this megacity. Hourly average of equivalent continuous sound pressure level (Leq), total number concentration of UFPs, mass concentration of PM2.5 and PM10, as well as traffic count and speed were simultaneously measured over a period of three days in winter. Additionally, meteorological data including temperature, relative humidity, wind speed and direction were collected in a weather station, located 3 km from the monitoring site. Noise levels showed relatively low temporal variability in near-highway environments compared to PM concentrations. Hourly average of Leq ranged from 63.8 to 69.9 dB(A) (mean ~ 68 dB(A)), while hourly concentration of particles varied from 30,800 to 108,800 cm-3 for UFP (mean ~ 64,500 cm-3), 41 to 75 µg m-3 for PM2.5 (mean ~ 53 µg m-3), and 62 to 112 µg m-3 for PM10 (mean ~ 88 µg m-3). The Pearson correlation coefficient revealed strong relationship between noise and UFP (r ~ 0.61) overall. Under downwind conditions, UFP number concentration showed the strongest association with noise level (r ~ 0.63). The coefficient decreased to a lesser degree under upwind conditions (r ~ 0.24) due to the significant role of wind and humidity in UFP dynamics. Furthermore, PM2.5 and PM10 correlated moderately with noise (r ~ 0.52 and 0.44 respectively). In general, traffic counts were more strongly associated with noise and PM compared to traffic speeds. It was concluded that noise level combined with meteorological data can be used as a proxy to estimate PM concentrations (specifically UFP number concentration) in near-highway environments of Tehran. However, it is important to measure joint variability of noise and particles to study their health effects in epidemiological studies.

Keywords: noise, particulate matter, PM10, PM2.5, ultrafine particle

Procedia PDF Downloads 180
3558 Critical Velocities for Particle Transport from Experiments and CFD Simulations

Authors: Sajith Sajeev, Brenton McLaury, Siamack Shirazi

Abstract:

In the petroleum industry, solid particles are often present along with the produced fluids. It is imperative to keep particles from accumulating in flow lines. In this study, various experiments are conducted to study sand particle transport, where critical velocity is defined as the average fluid velocity to keep particles continuously moving. Many parameters related to the fluid, particles and pipe affect the transport process. Experimental results are presented varying the particle concentration. Additionally, CFD simulations using a discrete element modeling (DEM) approach are presented to compare with experimental result.

Keywords: particle transport, critical velocity, CFD, DEM

Procedia PDF Downloads 298
3557 Design of Compact UWB Multilayered Microstrip Filter with Wide Stopband

Authors: N. Azadi-Tinat, H. Oraizi

Abstract:

Design of compact UWB multilayered microstrip filter with E-shape resonator is presented, which provides wide stopband up to 20 GHz and arbitrary impedance matching. The design procedure is developed based on the method of least squares and theory of N-coupled transmission lines. The dimensions of designed filter are about 11 mm × 11 mm and the three E-shape resonators are placed among four dielectric layers. The average insertion loss in the passband is less than 1 dB and in the stopband is about 30 dB up to 20 GHz. Its group delay in the UWB region is about 0.5 ns. The performance of the optimized filter design perfectly agrees with the microwave simulation softwares.

Keywords: method of least square, multilayer microstrip filter, n-coupled transmission lines, ultra-wideband

Procedia PDF Downloads 382