Search results for: slip control
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10996

Search results for: slip control

4246 Numerical and Experimental Studies on the Characteristic of the Air Distribution in the Wind-Box of a Circulating Fluidized Bed Boiler

Authors: Xiaozhou Liu, Guangyu Zhu, Yu Zhang, Hongwei Wu

Abstract:

The wind-box is one of the important components of a Circulating Fluidized Bed (CFB) boiler. The uniformity of air flow in the wind-box of is very important for highly efficient operation of the CFB boiler. Non-uniform air flow distribution within the wind-box can reduce the boiler's thermal efficiency, leading to higher energy consumptions. An effective measure to solve this problem is to install an air flow distributing device in the wind-box. In order to validate the effectiveness of the air flow distributing device, visual and velocity distribution uniformity experiments have been carried out under five different test conditions by using a 1:64 scale model of a 220t/hr CFB boiler. It has been shown that the z component of flow velocity remains almost the same at control cross-sections of the wind-box, with a maximum variation of less than 10%. Moreover, the same methodology has been carried out to a full-scale 220t/hr CFB boiler. The hot test results depict that the thermal efficiency of the boiler has increased from 85.71% to 88.34% when tested with an air flow distributing device in place, which is equivalent to a saving of 5,000 tons of coal per year. The economic benefits of this energy-saving technology have been shown to be very significant, which clearly demonstrates that the technology is worth applying and popularizing.

Keywords: circulating fluidized bed, CFB, wind-box, air flow distributing device, visual experiment, velocity distribution uniformity experiment, hot test

Procedia PDF Downloads 177
4245 Developing a Web-Based Workflow Management System in Cloud Computing Platforms

Authors: Wang Shuen-Tai, Lin Yu-Ching, Chang Hsi-Ya

Abstract:

Cloud computing is the innovative and leading information technology model for enabling convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort. In this paper, we aim at the development of workflow management system for cloud computing platforms based on our previous research on the dynamic allocation of the cloud computing resources and its workflow process. We took advantage of the HTML 5 technology and developed web-based workflow interface. In order to enable the combination of many tasks running on the cloud platform in sequence, we designed a mechanism and developed an execution engine for workflow management on clouds. We also established a prediction model which was integrated with job queuing system to estimate the waiting time and cost of the individual tasks on different computing nodes, therefore helping users achieve maximum performance at lowest payment. This proposed effort has the potential to positively provide an efficient, resilience and elastic environment for cloud computing platform. This development also helps boost user productivity by promoting a flexible workflow interface that lets users design and control their tasks' flow from anywhere.

Keywords: web-based, workflow, HTML5, Cloud Computing, Queuing System

Procedia PDF Downloads 309
4244 Compatibility of Copolymer-Based Grinding Aids and Sulfonated Acetone-Formaldehyde Superplasticizer

Authors: Zhang Tailong

Abstract:

Compatibility between sulfonated acetone-formalehyde superplasticizer (SAF) and copolymer-based grinding aids (GA) were studied by fluidity, Zeta potential, setting time of cement pasts, initial slump and slump flow of concrete and compressive strength of concrete. ESEM, MIP, and XRD were used to investigate the changing of microstructure of interior concrete. The results indicated that GA could noticeably enhance the dispersion ability of SAF. It was found that better fluidity and slump-keeping ability of cement paste were obtained in the case of GA. In addition, GA and SAF together had a certain retardation effect on hydration of cement paste. With increasing of the GA dosage, the dispersion ability and retardation effect of admixture increased. The compressive strength of the sample made with SAF and GA after 28 days was higher than that of the control sample made only with SAF. The initial slump and slump flow of concrete increased by 10.0% and 22.9%, respectively, while 0.09 wt.% GA was used. XRD examination indicated that new products were not found in the case of GA. In addition, more dense arrangement of hydrates and lower porosity of the specimen were observed by ESEM and MIP, which contributed to higher compressive strength.

Keywords: copolymer-based grinding aids, superplasiticizer, compatibility, microstructure, cement, concrete

Procedia PDF Downloads 247
4243 Occupational Health and Safety Implications of Flower Farming on the Local Communities in Central Uganda

Authors: Charles Owenda Omulo

Abstract:

This study examines Occupational Health and Safety implications in flower farms in Central Uganda. An exploratory sequential mixed method design and methodology was employed, with multiple data collection methods, including interviews, focus group discussions, and surveys. The findings show that occupational health and safety issues remain a major problem in flower farms. While the majority of workers agreed that the farms provided them with protective equipment, the data collected from the workers point to either the improper use or ineffectiveness of this equipment. A number of workers reported skin irritations, sore and painful eyes, stiff necks, back pains, and occasional headaches that were presumably argued to have arisen from their work environment. The study also found that farms have been adjusting in an attempt to correct some of these anomalies. These included the use of biological approaches to control pests and diseases and restricting the use of some chemical formulations that are deemed to be harmful to applicators and the environment. Alongside these efforts, the study recommends increased vigilance by the flower farm owners in the provision of personal protective equipment to workers.

Keywords: flower farms, personal protective equipment, agrochemicals, rural communities, occupational health and safety

Procedia PDF Downloads 65
4242 Aerodynamic Design Optimization of Ferrari F430 Flying Car with Enhanced Takeoff Performance

Authors: E. Manikandan, C. Chilambarasan, M. Sulthan Ariff Rahman, S. Kanagaraj, Abhimanyu Pugazhandhi, V. R. Sanal Kumar

Abstract:

The designer of any flying car has the major concern on the creation of upward force with low takeoff velocity, with minimum drag, coupled with better stability and control warranting its overall high performance both in road and air. In this paper, 3D numerical simulations of external flow of a Ferrari F430 fitted with different NACA series rectangular wings have been carried out for finding the best aerodynamic design option in road and air. The principle that allows a car to rise off the ground by creating lift using deployable wings with desirable lifting characteristics is the main theme of our paper. Additionally, the car body is streamlined in accordance with the speed range. Further, the rounded and tapered shape of the top of the car is designed to slice through the air and minimize the wind resistance. The 3D SST k-ω turbulence model has been used for capturing the intrinsic flow physics during the take off phase. In the numerical study, a fully implicit finite volume scheme of the compressible, Reynolds-Averaged, Navier-Stokes equations is employed. Through the detailed parametric analytical studies, we have conjectured that Ferrari F430 can be converted into a lucrative flying car with best fit NACA wing through a proper aerodynamic design optimization.

Keywords: aerodynamics of flying car, air taxi, Ferrari F430, roadable airplane

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4241 Effects of Soil Erosion on Vegetation Development

Authors: Josephine Wanja Nyatia

Abstract:

The relationship between vegetation and soil erosion deserves attention due to its scientific importance and practical applications. A great deal of information is available about the mechanisms and benefits of vegetation in the control of soil erosion, but the effects of soil erosion on vegetation development and succession is poorly documented. Research shows that soil erosion is the most important driving force for the degradation of upland and mountain ecosystems. Soil erosion interferes with the process of plant community development and vegetation succession, commencing with seed formation and impacting throughout the whole growth phase and affecting seed availability, dispersal, germination and establishment, plant community structure and spatial distribution. There have been almost no studies on the effects of soil erosion on seed development and availability, of surface flows on seed movement and redistribution, and their influences on soil seed bank and on vegetation establishment and distribution. However, these effects may be the main cause of low vegetation cover in regions of high soil erosion activity, and these issues need to be investigated. Moreover, soil erosion is not only a negative influence on vegetation succession and restoration but also a driving force of plant adaptation and evolution. Consequently, we need to study the effects of soil erosion on ecological processes and on development and regulation of vegetation succession from the points of view of pedology and vegetation, plant and seed ecology, and to establish an integrated theory and technology for deriving practical solutions to soil erosion problems

Keywords: soil erosion, vegetation, development, seed availability

Procedia PDF Downloads 87
4240 Stability Analysis of DC Microgrid with Varying Supercapacitor Operating Voltages

Authors: Annie B. V., Anu A. G., Harikumar R.

Abstract:

Microgrid (MG) is a self-governing miniature section of the power system. Nowadays the majority of loads and energy storage devices are inherently in DC form. This necessitates a greater scope of research in the various types of energy storage devices in DC microgrids. In a modern power system, DC microgrid is a manageable electric power system usually integrated with renewable energy sources (RESs) and DC loads with the help of power electronic converters. The stability of the DC microgrid mainly depends on the power imbalance. Power imbalance due to the presence of intermittent renewable energy resources (RERs) is supplied by energy storage devices. Battery, supercapacitor, flywheel, etc. are some of the commonly used energy storage devices. Owing to the high energy density provided by the batteries, this type of energy storage system is mainly utilized in all sorts of hybrid energy storage systems. To minimize the stability issues, a Supercapacitor (SC) is usually interfaced with the help of a bidirectional DC/DC converter. SC can exchange power during transient conditions due to its high power density. This paper analyses the stability issues of DC microgrids with hybrid energy storage systems (HESSs) arises from a reduction in SC operating voltage due to self-discharge. The stability of DC microgrid and power management is analyzed with different control strategies.

Keywords: DC microgrid, hybrid energy storage system (HESS), power management, small signal modeling, supercapacitor

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4239 PDMS-Free Microfluidic Chips Fabrication and Utilisation for Pulsed Electric Fields Applications

Authors: Arunas Stirke, Neringa Bakute, Gatis Mozolevskis

Abstract:

A technology of microfluidics is an emerging tool in the field of biology, medicine and chemistry. Microfluidic device is also known as ‘lab-on-a-chip’ technology [1]. In moving from macro- to microscale, there is unprecedented control over spatial and temporal gradients and patterns that cannot be captured in conventional Petri dishes and well plates [2]. However, there is not a single standard microfluidic chip designated for all purposes – every different field of studies needs a specific microchip with certain geometries, inlet/outlet, channel depth and other parameters to precisely regulate the required function. Since our group is studying an effect of pulsed electric field (PEF) to the cells, we have manufactured a microfluidic chip designated for high-throughput electroporation of cells. In our microchip, a cell culture chamber is divided into two parallel channels by a membrane, meanwhile electrodes for electroporation are attached to the wall of the channels. Both microchannels have their own inlet and outlet, enabling injection of transfection material separately. Our perspective is to perform electroporation of mammalian cells in two different ways: (1) plasmid and cells are injected in the same microchannel and (2) injected into separate microchannels. Moreover, oxygen and pH sensors are integrated on order to analyse cell viability parameters after PEF treatment.

Keywords: microfluidics, chip, fabrication, electroporation

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4238 Development of Calcium Carbonate Molecular Sheets via Wet Chemical Route

Authors: Sudhir Kumar Sharma, Ramesh Jagannathan

Abstract:

The interaction of organic and inorganic matrices of biological origin resulting in self-assembled structures with unique properties is well established. The development of such self-assembled nanostructures by synthetic and bio-inspired techniques is an established field of active research. Among bio-materials, nacre, a laminar stack of calcium carbonate nanosheets, which are interleaved with organic material, has long been focused research due to its unique mechanical properties. In this paper, we present the development of nacre-like lamellar structures made up of calcium carbonate via a wet chemical route. We used the binding affinity of carboxylate anions and calcium cations using poly (acrylic) acid (PAA) to lead CaCO₃ crystallization. In these experiments, we selected calcium acetate as the precursor molecule along with PAA (Mw ~ 8000 Da). We found that Ca⁺²/COO⁻ ratio provided a tunable control for the morphology and growth of CaCO₃ nanostructures. Drop casting one such formulation on a silicon substrate followed by calcination resulted in co-planner, molecular sheets of CaCO₃, separated by a spacer layer of carbon. The scope of our process could be expanded to produce unit cell thick molecular sheets of other important inorganic materials.

Keywords: self-assembled structures, bio-inspired materials, calcium carbonate, wet chemical route

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4237 The Robot Physician's (Rp-7) Management and Care in Unstable Oncology Patients

Authors: Alisher Agzamov, Hanan Al Harbi

Abstract:

BACKGROUND: The timely assessment and treatment of ICU Surgical and Medical Oncology patients is important for Oncology surgeons and Medical Oncologists and Intensivists (1). We hypothesized that the use of Robot Physician’s (RP - 7) ICU management and care in ICU can improve ICU physician rapid response to unstable ICU Oncology patients. METHODS: This is a prospective study of 1501 oncology patients using a before-after, cohort-control design to test the effectiveness of RP. We have used RP to make multidisciplinary ICU rounds in the ICU and for Emergency cases. Data concerning several aspects of the RP interaction, including the latency of the response, the problem being treated, the intervention that was ordered, and the type of information gathered using the RP, were documented. The effect of RP on ICU length of stay and cost was assessed. RESULTS: The use of RP was associated with a reduction in latency of attending physician face-to-face response for routine and urgent pages compared to conventional care (RP: 10.2 +/- 3.3 minutes vs conventional: 210 +/- 40 minutes). The response latencies to Oncology Emergency (8.0 +/- 2.8 vs 140 +/- 35 minutes) and for Respiratory Failure (12 +/- 04 vs 110 +/- 45 minutes) were reduced (P < .001), as was the LOS for oncology patients (5 days) and ARDS (10 day). There was an increase in ICU occupancy by 29 % compared with the prerobot era, and there was an ICU cost savings of KD2.2 million attributable to the use of RP. CONCLUSION: The use of RP enabled rapid face-to-face ICU Intensivist - physician response to unstable ICU Oncology patients and resulted in decreased ICU cost and LOS.

Keywords: robot physician, oncology patients, icu management and care, cost and icu occupancy

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4236 The Reflection Framework to Enhance the User Experience for Cultural Heritage Spaces’ Websites in Post-Pandemic Times

Authors: Duyen Lam, Thuong Hoang, Atul Sajjanhar, Feifei Chen

Abstract:

With the emerging interactive technology applications helping users connect progressively with cultural artefacts in new approaches, the cultural heritage sector gains significantly. The interactive apps’ issues can be tested via several techniques, including usability surveys and usability evaluations. The severe usability problems for museums’ interactive technologies commonly involve interactions, control, and navigation processes. This study confirms the low quality of being immersive for audio guides in navigating the exhibition and involving experience in the virtual environment, which are the most vital features of new interactive technologies such as AR and VR. In addition, our usability surveys and heuristic evaluations disclosed many usability issues of these interactive technologies relating to interaction functions. Additionally, we use the Wayback Machine to examine what interactive apps/technologies were deployed on these websites during the physical visits limited due to the COVID-19 pandemic lockdown. Based on those inputs, we propose the reflection framework to enhance the UX in the cultural heritage domain with detailed guidelines.

Keywords: framework, user experience, cultural heritage, interactive technology, museum, COVID-19 pandemic, usability survey, heuristic evaluation, guidelines

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4235 Smart Interior Design: A Revolution in Modern Living

Authors: Fatemeh Modirzare

Abstract:

Smart interior design represents a transformative approach to creating living spaces that integrate technology seamlessly into our daily lives, enhancing comfort, convenience, and sustainability. This paper explores the concept of smart interior design, its principles, benefits, challenges, and future prospects. It also highlights various examples and applications of smart interior design to illustrate its potential in shaping the way we live and interact with our surroundings. In an increasingly digitized world, the boundaries between technology and interior design are blurring. Smart interior design, also known as intelligent or connected interior design, involves the incorporation of advanced technologies and automation systems into residential and commercial spaces. This innovative approach aims to make living environments more efficient, comfortable, and adaptable while promoting sustainability and user well-being. Smart interior design seamlessly integrates technology into the aesthetics and functionality of a space, ensuring that devices and systems do not disrupt the overall design. Sustainable materials, energy-efficient systems, and eco-friendly practices are central to smart interior design, reducing environmental impact. Spaces are designed to be adaptable, allowing for reconfiguration to suit changing needs and preferences. Smart homes and spaces offer greater comfort through features like automated climate control, adjustable lighting, and customizable ambiance. Smart interior design can significantly reduce energy consumption through optimized heating, cooling, and lighting systems. Smart interior design integrates security systems, fire detection, and emergency response mechanisms for enhanced safety. Sustainable materials, energy-efficient appliances, and waste reduction practices contribute to a greener living environment. Implementing smart interior design can be expensive, particularly when retrofitting existing spaces with smart technologies. The increased connectivity raises concerns about data privacy and cybersecurity, requiring robust measures to protect user information. Rapid advancements in technology may lead to obsolescence, necessitating updates and replacements. Users must be familiar with smart systems to fully benefit from them, requiring education and ongoing support. Residential spaces incorporate features like voice-activated assistants, automated lighting, and energy management systems. Intelligent office design enhances productivity and employee well-being through smart lighting, climate control, and meeting room booking systems. Hospitals and healthcare facilities use smart interior design for patient monitoring, wayfinding, and energy conservation. Smart retail design includes interactive displays, personalized shopping experiences, and inventory management systems. The future of smart interior design holds exciting possibilities, including AI-powered design tools that create personalized spaces based on user preferences. Smart interior design will increasingly prioritize factors that improve physical and mental health, such as air quality monitoring and mood-enhancing lighting. Smart interior design is revolutionizing the way we interact with our living and working spaces. By embracing technology, sustainability, and user-centric design principles, smart interior design offers numerous benefits, from increased comfort and convenience to energy efficiency and sustainability. Despite challenges, the future holds tremendous potential for further innovation in this field, promising a more connected, efficient, and harmonious way of living and working.

Keywords: smart interior design, home automation, sustainable living spaces, technological integration, user-centric design

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4234 Guadua Bamboo as Eco-Friendly Element in Interior Design and Architecture

Authors: Sarah Noaman

Abstract:

Utilizing renewable resources has become extensive solution for most problems in Egypt nowadays. It plays role in environmental issues such as energy crisis, lake of natural resources and climate change. This paper focuses on the importance of working with the key concepts of creating eco-friendly spaces in Egypt by using traditional perennial plants, such as Guadua bamboo as renewable resources in structures manufacture. Egypt is in critical need to search for alternative raw materials. Thus, this paper focuses on studying the usage of neglected yet affordable materials, such as Guadua bamboo in light weight structures and digital fabrication. Guadua bamboo has been cultivated throughout in tropical and subtropical areas. In Egypt, they exist in many rural areas where people try to control their growth by using pesticides as it serves no economic purpose. This paper aims to discuss the usage of Guadua bamboo either in its original state or after fabrication in the context of interior design and architecture. The results will show the applicability of using perennial plants as complementary materials in the manufacturing processes; also the conclusion will focus the lights on the importance of re-forming shallow water plants in interior design and architecture.

Keywords: digital fabrication, Guadua bamboo, zero-waste material, sustainable material, interior architecture

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4233 Research on Natural Lighting Design of Atriums Based on Energy-Saving Aim

Authors: Fan Yu

Abstract:

An atrium is a place for natural climate exchanging of indoor and outdoor space of buildings, which plays an active role in the overall energy conservation, climate control and environmental purification of buildings. Its greatest contribution is serving as a natural light collector and distributor to solve the problem of natural lighting in large and deep spaces. However, in real situations, the atrium space often results in energy consumption due to improper design in considering its big size and large amount use of glass. Based on the purpose of energy conservation of buildings, this paper emphasizes the significance of natural lighting of atriums. Through literature research, case analysis and other methods, four factors, namely: the light transmittance through the top of the atrium, the geometric proportion of the atrium space, the size and position of windows and the material of the surface of walls in the atrium, were studied, and the influence of different architectural compositions on the natural light distribution of the atrium is discussed. Relying on the analysis of relevant cases, it is proposed that when designing the natural lighting of the atrium, the height and width of the atrium should be paid attention to, the atrium walls are required being rough surfaces and the atrium top-level windows need to be minimized in order to introduce more natural light into the buildings and achieve the purpose of energy conservation.

Keywords: energy conservation, atrium, natural lighting, architectural design

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4232 The Relation between Body Mass Index and Menstrual Cycle Disorders in Medical Students of University Pelita Harapan, Indonesia

Authors: Gabriella Tjondro, Julita Dortua Laurentina Nainggolan

Abstract:

Introduction: There are several things affecting menstrual cycle, namely, nutritional status, diet, financial status of one’s household and exercises. The most commonly used parameter to calculate the fat in a human body is body mass index. Therefore, it is necessary to do research to prevent complications caused by menstrual disorder in the future. Design Study: This research is an observational analytical study with the cross-sectional-case control approach. Participants (n = 124; median age = 19.5 years ± SD 3.5) were classified into 2 groups: normal, NM (n = 62; BMI = 18-23 kg/m2) and obese, OB (n = 62; BMI = > 25 kg/m2). BMI was calculated from the equation; BMI = weight, kg/height, m2. Results: There were 79.10% from obese group who experienced menstrual cycle disorders (n=53, 79.10%; p value 0.00; OR 5.25) and 20.90% from normal BMI group with menstrual cycle disorders. There were several factors in this research that also influence the menstrual cycle disorders such as stress (44.78%; p value 0.00; OR 1.85), sleep disorders (25.37%; p value 0.00; OR 1.01), physical activities (25.37%; p value 0.00; OR 1.24) and diet (10.45%; p value 0.00; OR 1.07). Conclusion: There is a significant relation between body mass index (obese) and menstrual cycle disorders. However, BMI is not the only factor that affects the menstrual cycle disorders. There are several factors that also can affect menstrual cycle disorders, in this study we use stress, sleep disorders, physical activities and diet, in which none of them are dominant.

Keywords: menstrual disorders, menstrual cycle, obesity, body mass index, stress, sleep disorders, physical activities, diet

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4231 An Evaluation of the Impact of Social Media on Nigerian Youths

Authors: Haruna Shola Adeosun, Lekan M. Togunwa, Ajoke F. Adebiyi

Abstract:

This paper examines the impact of social media on Nigerian Youths particularly in Nigeria. This study reviewed secondary sources data. The research adopted survey method which involves the use of questionnaire that was administered to gather primary data analysis and presentation were done with the use of tables, figures, percentages and chi-square were used to test the hypotheses formulated. The study revealed that social media consumers, especially Facebook are prone to the benefits or risks aspect of its contents. At this expense, what user derived, seeks, sought and gains from such media depend on the motive they are being used for. The study also revealed that users have the tendency to be positively influenced through heavy or over exposure to numerous contents that are damaging and harmful. This means that social media usage may be considered as good or bad. As its contents may or may not subject consumers to vulnerable use depending on what is saved from it. The study recommends that the use of Facebook should be subjected to gate keeping and monitoring in order to control the activities of users that embrace depression, bullying, sexing and sexual harassment as a way of life. Parents should close watch on their children and caution them towards cultivating the habit of over exposure to social sites so at to protect them form risks social media poses.

Keywords: evaluation, impact, soocial media, nigerian youths

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4230 Utilization of Complete Feed Based on Ammoniated Corn Waste on Bali Cattle Peformance

Authors: Elihasridas, Rusmana Wijaya Setia Ninggrat

Abstract:

This research aims to study the utilization of ammoniated corn waste complete ration for substitution basal ration of natural grass in Bali cattle. Four treatments (complete feed ration consisted of: R1=40% natural grass + 60% concentrate (control), R2= 50% natural grass+50% concentrate, R3=60% natural grass+40% concentrate and R4=40% ammoniated corn waste+60% concentrate) were employed in this experiment. This experiment was arranged in a latin square design. Observed variables included dry matter intake (DMI), average daily gain and feed conversion. Data were analyzed by using the Analysis of Variance following a 4 x 4 Latin Square Design. The DMI for R1was 7,15kg/day which was significantly (P < 0,05) higher than R2 (6,32 kg/day) and R3(6,07 kg/day), but was not significantly different (P < 0,05) from R4 (7,01 kg/day). Average daily gain for R1(0,75 kg/day) which was significantly (P < 0,05) higher than R2(0,66 kg/day) and R3 (0,61 kg/day),but was not significantly different (P > 0,05) from R4(0,74 kg/day). Feed conversion was not significantly affected (P > 0,05) by ration. It was concluded that ammoniated corn waste complete ration (40% ammoniated corn waste + 60% concentrate) could be utilized for substitution natural grass basal ration.

Keywords: ammoniated corn waste, bali cattle, complete feed, daily gain

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4229 Enhancing Throughput for Wireless Multihop Networks

Authors: K. Kalaiarasan, B. Pandeeswari, A. Arockia John Francis

Abstract:

Wireless, Multi-hop networks consist of one or more intermediate nodes along the path that receive and forward packets via wireless links. The backpressure algorithm provides throughput optimal routing and scheduling decisions for multi-hop networks with dynamic traffic. Xpress, a cross-layer backpressure architecture was designed to reach the capacity of wireless multi-hop networks and it provides well coordination between layers of network by turning a mesh network into a wireless switch. Transmission over the network is scheduled using a throughput-optimal backpressure algorithm. But this architecture operates much below their capacity due to out-of-order packet delivery and variable packet size. In this paper, we present Xpress-T, a throughput optimal backpressure architecture with TCP support designed to reach maximum throughput of wireless multi-hop networks. Xpress-T operates at the IP layer, and therefore any transport protocol, including TCP, can run on top of Xpress-T. The proposed design not only avoids bottlenecks but also handles out-of-order packet delivery and variable packet size, optimally load-balances traffic across them when needed, improving fairness among competing flows. Our simulation results shows that Xpress-T gives 65% more throughput than Xpress.

Keywords: backpressure scheduling and routing, TCP, congestion control, wireless multihop network

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4228 Randomly Casted Single-Wall Carbon Nanotubes Films for High Performance Hybrid Photovoltaic Devices

Authors: My Ali El Khakani

Abstract:

Single-wall Carbon nanotubes (SWCNTs) possess an unprecedented combination of unique properties that make them highly promising for suitable for a new generation of photovoltaic (PV) devices. Prior to discussing the integration of SWCNTs films into effective PV devices, we will briefly highlight our work on the synthesis of SWCNTs by means of the KrF pulsed laser deposition technique, their purification and transfer onto n-silicon substrates to form p-n junctions. Some of the structural and optoelectronic properties of SWCNTs relevant to PV applications will be emphasized. By varying the SWCNTs film density (µg/cm2), we were able to point out the existence of an optimum value that yields the highest photoconversion efficiency (PCE) of ~10%. Further control of the doping of the p-SWCNTs films, through their exposure to nitric acid vapors, along with the insertion of an optimized hole-extraction-layer in the p-SWCNTs/n-Si hybrid devices permitted to achieve a PCE value as high as 14.2%. Such a high PCE value demonstrates the full potential of these p-SWCNTs/n-Si devices for sunlight photoconversion. On the other hand, by examining both the optical transmission and electrical conductance of the SWCNTs’ films, we established a figure of merit (FOM) that was shown to correlate well with the PCE performance. Such a direct relationship between the FOM and the PCE can be used as a guide for further PCE enhancement of these novel p-SWCNTs/n-Si PV devices.

Keywords: carbon nanotubes (CNTs), CNTs-silicon hybrid devices, photoconversion, photovoltaic devices, pulsed laser deposition

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4227 Biocontrol Potential of Trichoderma sp. against Macrophomina phaseolina

Authors: Jayarama Reddy, Anand S., H., Sundaram, Jeldi Hemachandran

Abstract:

Forty two strains of Trichoderma sp. were isolated from cultivated lands around Bangalore and analyzed for their antagonistic potential against Macrophomina phaseolina. The potential of biocontrol agents ultimately lies in their capacity to control pathogens in vivo. Bioefficacy studies were hence conducted using chickpea (Cicer arientum c.v. Annigeri) as an experimental plant by the roll paper towel method. Overall the isolates T6, T35, T30, and T25 showed better antagonistic potential in addition to enhancing plant growth. The production of chitinases to break down the mycelial cell walls of fungal plant pathogens has been implicated as a major cause of biocontrol activity. In order to study the mechanism of biocontrol against Macrophomina phaseolina, ten better performing strains were plated on media, amended with colloidal chitin and Sclerotium rolfsii cell wall extract. All the isolates showed chitinolytic activity on day three as well as day five. Production of endochitinase and exochitinase were assayed in liquid media using colloidal chitin amended broth. Strains T35 and T6 displayed maximum endochitinase and exochitinase activity. Although all strains exhibited cellulase activity, the quantum of enzyme produced was higher in T35 and T6. The results also indicate a positive correlation between enzyme production and bioefficacy.

Keywords: biocontrol, bioefficacy, cellulase, chitinase

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4226 Lewis Turning Point in China: Interviewing Perceptions of Fertility Policies by Unmarried Female Millennials

Authors: Yunqi Wang

Abstract:

Benefiting from the demographic dividend, China has enjoyed export-led economic growth since 1978. While Lewis's model marks the structural transformation from the low-wage 'subsistence' sector to the 'modern sector' as the end of labour surplus, the Chinese government seems eager to extend such benefit by promoting a series of fertility encouragement policies, contrasting to its firm and strict birth control since last century. Based on a Attride-Stirling’s thematic analysis of interviews with unmarried female millennials in China, this paper argues that the young female generation responded to current fertility policies negatively, where the policy ineffectiveness and irresponsiveness have further worsened their marriage and childbirth reluctance. Instead of focusing on changes in wage level, this research contributes a qualitative perspective to the existing theoretical debate on the Lewis turning point, implying an inevitable end of demographic dividend in China. Highlighting the greater focus on female consciousness among the younger generation, it also suggests a policy orientation towards resolving outdated social norms to accommodate the rising female consciousness since millennials will become the childbirth mainstay in forthcoming years.

Keywords: lewis model, fertility policy, demographic dividend, one-child policy

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4225 Analysis of Learning Difficulties among Preservice Students towards Science Education

Authors: Nahla Khatib

Abstract:

This study investigated several learning difficulties that affected the classroom learning experience of preservice students who are studying general science and methods of teaching science students at Faculty of Educational Studies at the Arab Open University (AOU) in Amman, Jordan. The focus questions for this study were to find answers for the following: 1. What are the main areas of learning difficulty among preservice students towards science education? 2. What are the main aspects of reducing obstacles towards success in science education? To achieve this goal, the researcher prepared a questionnaire which included 30 items to point out the learning difficulties among preservice students towards science education. The questionnaire was distributed among students enrolled in the general science courses 1&2 and methods of teaching science courses at the beginning of the spring semester of year (2013-2014). After collecting the filled questionnaire a descriptive statistical analysis was carried out (means and standard deviation) for the items of the questionnaire. After analyzing the data statistically our findings showed that student control–factors as well as course controlled factor, factors related to the nature of science, and factors related to the role of instructor affected student success toward science education. The study was concluded with a number of recommendations.

Keywords: nature of science, preservice teachers, science education, learning difficulties

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4224 Trauma: Constructivist Theoretical Framework

Authors: Wendi Dunham, Kimberly Floyd

Abstract:

The constructivist approach to learning is a theoretical orientation that posits that individuals create their own understanding and knowledge of the world through their experiences and interactions. This approach emphasizes that learning is an active process and that individuals are not passive recipients when constructing their understanding of their world. When used concurrently with trauma-informed practices, a constructivist approach can inform the development of a framework for students and teachers that supports their social, emotional, and mental health in addition to enabling academic success. This framework can be applied to teachers and students. When applied to teachers, it can be used to achieve purposeful coping mechanisms through restorative justice and dispositional mindfulness. When applied to students, the framework can implement proactive, student-based practices such as Response to Intervention (RtI) and the 4 Rs to connect resiliency and intervention to academic learning. Using a constructivist, trauma-informed framework can provide students with a greater sense of control and agency over their trauma experiences and impart confidence in achieving school success.

Keywords: trauma, trauma informed practices in education, constructivist theory framework, school responses to trauma, trauma informed supports for teachers, trauma informed strategies for students, restorative justice, mindfulness, response to intervention, the 4 R's, resiliency

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4223 Design of Raw Water Reservoir on Sandy Soil

Authors: Venkata Ramana Pamu

Abstract:

This paper is a case study of a 5310 ML capacity Raw Water Reservoir (RWR), situated in Indian state Rajasthan, which is a part of Rajasthan Rural Water Supply & Fluorosis Mitigation Project. This RWR embankment was constructed by locally available material on natural ground profile. Height of the embankment was varying from 2m to 10m.This is due to existing ground level was varying. Reservoir depth 9m including 1.5m free board and 1V:3H slopes were provided both upstream and downstream side. Proper soil investigation, tests were done and it was confirmed that the existing soil is sandy silt. The existing excavated earth was used as filling material for embankment construction, due to this controlling seepage from upstream to downstream be a challenging task. Slope stability and Seismic analysis of the embankment done by Conventional method for both full reservoir condition and rapid drawdown. Horizontal filter at toe level was provided along with upstream side PCC (Plain Cement Concrete) block and HDPE (High Density poly ethylene) lining as a remedy to control seepage. HDPE lining was also provided at storage area of the reservoir bed level. Mulching was done for downstream side slope protection.

Keywords: raw water reservoir, seepage, seismic analysis, slope stability

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4222 Efficacy of Ginger (Zingiber officinale) and a Zeolite (Hydrated Sodium Calcium Aluminosilicate) in the Amelioration of Aflatoxicosis in Broilers

Authors: Ryan Stevens, Wayne L. Bryden

Abstract:

This study focused on the effects of ginger and a zeolite (toxin binder) in reducing the toxic effects of aflatoxin B1 (AFB1) in broiler chickens 7 to 49 days of age. The chicks were maintained normally until experimental diets were introduced on day 7 post-hatching. Nine hundred and thirty six, 7-d-old broiler chickens were randomly assigned to 18 treatment groups; each group had four replicates, each with 13 chickens. The experimental groups or diets had factorial combinations of the following; AFB1 0, 1 and 2 mg/kg diet, ginger 0 and 5g/kg diet, and zeolite 0, 15 and 30 g/kg diet. Diets were based on corn and soybean meal and a starter diet was fed from 1 to 14 days, a grower diet from15 to 28 days and a finisher diet was provided from day 29 until the end of the experiment. Both dietary levels of AFB1 decreased (P<0.05) body weight and feed conversion, and increased relative liver weights. Independent dietary inclusion of ginger or zeolite restored chick performance when diets contained 1mg/kg but not at 2mg/kg. Supplementation of zeolite together with ginger improved performance of birds fed contaminated diets. Interestingly, adding ginger to the control diet that was not contaminated with AFB1 improved (P<0.05) performance. Our results suggest that toxin binders and ginger can provide protection against the negative effects of AFB1 on performance of broiler chicks.

Keywords: aflatoxin, broiler, ginger, zeolite

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4221 Arsenic and Mercury Levels in Scalp Hair of School Children of Three Villages in Kandal Province, Cambodia

Authors: Alireza Yavar, Sukiman Sarmani, Khoo Kok Siong

Abstract:

The residents of villages in Kandal province of Cambodia, because of dietary habits, lifestyle and ecological conditions, are exposed to toxic elements like arsenic (As) and mercury (Hg). For comparison purpose, scalp hair samples of 12-17 school children from three villages of Anglong Romiot (AR), Svay Romiot (SR) and Kampong Kong (KK) in Kandal province of Cambodia were considered using k0- instrumental neutron activation method (k0-INAA). The samples irradiated 6 hours with 750 kW power in Malaysian nuclear agency (MNA) research reactor and subsequently found gamma peaks of radionuclides in samples using HPGe detector. The average values of arsenic and mercury were 0.0 and 3.52 (mg/kg) in AR; 1.88 and 4.26 (mg/kg) in SR; 2.81 and 3.37 (mg/kg) in KK, respectively. The results indicate KK, SR, and AR villages were in high, medium and control level of arsenic pollution, respectively. However, Hg concentration were highest in SR, then KK and AR villages, respectively. The accuracy of the method was assessed by analyzing ERM-DB001-human hair as certified reference materials (CRMs), which experimental result of ERM-DB001 was consistent with certified values. In addition, correlation between As and Hg levels was found by Pearson’s correlation test.

Keywords: Kandal province of Cambodia, k0- instrumental neutron activation method., scalp human hair, arsenic and mercury

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4220 Post Occupancy Evaluation in Higher Education

Authors: Balogun Azeez Olawale, Azeez S. A.

Abstract:

Post occupancy evaluation (POE) is a process of assessing building performance for its users and intended function during the occupation. User satisfaction impacts the performance of educational environments and their users: students, faculty, and staff. In addition, buildings are maintained and managed by teams that spend a large amount of time and capital on their long-term sustenance. By evaluating the feedback from users of higher education facilities, university planning departments are more prepared to understand the inputs for programming and future project planning. In addition, university buildings will be closer to meeting user and maintenance needs. This paper reports on a research team made up of academics, facility personnel, and users that have developed a plan to improve the quality of campus facilities through a POE exercise on a recently built project. This study utilized a process of focus group interviews representing the different users and subsequent surveys. The paper demonstrates both the theory and practice of POE in higher education and learning environment through the case example of four universities in Nigeria's POE exercise.

Keywords: post occupancy evaluation, building performance, building analysis, building evaluation, quality control, building assessment, facility management, design quality

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4219 Importance of Access to Public Information on Modern Slavery for Brazil's Livestock Sector

Authors: Juliana Brandao, Holly Gibbs, Lisa Naughton, Lisa Rausch

Abstract:

The Brazilian Amazon continues to be plagued by modern day slave labor, specifically within the cattle production industry. In response to this issue, modern day anti-slavery activists have implemented additional regulations designed to combat slave labor associated with cattle. These regulations have been incorporated into existing agreements designed to control deforestation. The goal of these rules is to prevent the trade of beef contaminated with modern slave labor between supplier farms and slaughterhouses. In this study, we identify farms that make use of modern slave labor, and we use cattle transaction data to track the sale of cattle between farms and slaughterhouses. Our analysis reveals that slaughterhouses, which have signed cattle agreements that include requirements to refuse cattle associated with modern slave labor, have avoided buying cattle from suppliers that were on the dirty list. This trend is especially evident when the "dirty lists" that identify modern-day slave labor users are made publicly accessible online. We conclude that the "dirty list" of modern-day slave labor users should be maintained on publicly available websites to allow slaughterhouses, retailers, and consumers to send powerful market signals that discourage the use of modern-day slave labor.

Keywords: cattle ranchers, modern slave labor, deforestation, brazilian amazon

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4218 the fairness of meritocracy and Korean Democracy-What makes the Korean youth accept the fairness of meritocracy??

Authors: WooJin KANG

Abstract:

Contrary to the ideal, in the cartelized democracy, meritocracy is revealed to be a system that gives arrogance to the winners and humiliation to the losers, and more and more studies are asserting the upper-class bias of meritocracy. However, only some studies have analyzed the determinants of the perception of meritocracy and fairness among young people. This article was an attempt to fill this gap. According to the empirical results of this article, the determinants of fairness of the meritocracy in the youth were multidimensional. The social status model, the political ideology model, and the future prospect model all significantly impacted the perception of meritocracy fairness among young people. Contrary to the predictions of the system justification theory and the compensatory control theory of previous studies, the lower-class youth were critical of meritocracy. In addition, the more negative the future outlook, the less they accepted the fairness of meritocracy. In addition, ideological debates over solutions to inequality of opportunity, which began in earnest during the 20th presidential election, turned out to be a variable that significantly influenced the perception of fairness based on meritocracy among young people. The results of the empirical analysis in this article reaffirmed the multidimensional structure of the youth. This suggests the need for policy responses leading to education tailored to various subgroups within the youth.

Keywords: Meritocracy, Exam-Meritocracy, Fairness, Multiple-inequality

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4217 Recovery and Εncapsulation of Μarine Derived Antifouling Agents

Authors: Marina Stramarkou, Sofia Papadaki, Maria Kaloupi, Ioannis Batzakas

Abstract:

Biofouling is a complex problem of the aquaculture industry, as it reduces the efficiency of the equipment and causes significant losses of cultured organisms. Nowadays, the current antifouling methods are proved to be labor intensive, have limited lifetime and use toxic substances that result in fish mortality. Several species of marine algae produce a wide variety of biogenic compounds with antibacterial and antifouling properties, which are effective in the prevention and control of biofouling and can be incorporated in antifouling coatings. In the present work, Fucus spiralis, a species of macro algae, and Chlorella vulgaris, a well-known species of microalgae, were used for the isolation and recovery of bioactive compounds, belonging to groups of fatty acids, lipopeptides and amides. The recovery of the compounds was achieved through the application of the ultrasound- assisted extraction, an environmentally friendly method, using green, non-toxic solvents. Moreover, the coating of the antifouling agents was done by innovative encapsulation and coating methods, such as electro-hydrodynamic process. For the encapsulation of the bioactive compounds natural matrices were used, such as polysaccharides and proteins. Water extracts that were incorporated in protein matrices were considered the most efficient antifouling coating.

Keywords: algae, electrospinning, fatty acids, ultrasound-assisted extraction

Procedia PDF Downloads 342