Search results for: load resistant factor design
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 19174

Search results for: load resistant factor design

4654 Scientific Insight Review of Corrosion Methods and Corrosion Control of Pre-Stressed Concrete Cylinder Pipes

Authors: Saad A. Bakheet, Ashraf A. Younees, Abdalsamia M. Falah

Abstract:

The main purpose of this study is to the occurrence of several failures in four-meter diameter pre-restressed concrete cylinder pipes, which transport a huge quantity of water from the Libyan Sahara Desert to the populated coastal area in the north. This study will help to address the problems related to corrosion of the pre-stressed concrete cylinder pipes and methods of controlling it. The methodologies used depended on reviewing the design and fabrication of pre-stressed concrete cylinder pipes and studying the cause of the corrosion, which resulted in the failure of the pre-stressed concrete cylinder pipe Man-Made River project in Libya. The chloride-induced corrosion penetrating through the mortar coat was the main reason for corrosion. The beginning of the occurrence of corrosion, its causes, and the mechanisms of its development in pre-stressed concrete pipes since 1937 have been reviewed and are continuing until now. Manufacturing technology control corrosion and all associated problems and technology to control it have been demonstrated, including variables during manufacture, the use of a modified coating, and cathodic protection systems. It has been revised and is still based on international standards. The development of these standards and the change in some of their technical contents reflect the world's interest in the problems of corrosion and the cost of maintenance and replacement.

Keywords: PCCP corrosion, international standard, coating system, failure assessment

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4653 Reclamation of Molding Sand: A Chemical Approach to Recycle Waste Foundry Sand

Authors: Mohd Moiz Khan, S. M. Mahajani, G. N. Jadhav

Abstract:

Waste foundry sand (total clay content 15%) contains toxic heavy metals and particulate matter which make dumping of waste sand an environmental and health hazard. Disposal of waste foundry sand (WFS) remains one of the substantial challenges faced by Indian foundries nowadays. To cope up with this issue, the chemical method was used to reclaim WFS. A stirrer tank reactor was used for chemical reclamation. Experiments were performed to reduce the total clay content from 15% to as low as 0.9% in chemical reclamation. This method, although found to be effective for WFS reclamation, it may face a challenge due to the possibly high operating cost. Reclaimed sand was found to be satisfactory in terms of sand qualities such as total clay (0.9%), active clay (0.3%), acid demand value (ADV) (2.6%), loss on igniting (LOI) (3 %), grain fineness number (GFN) (56), and compressive strength (60 kPa). The experimental data generated on chemical reactor under different conditions is further used to optimize the design and operating parameters (rotation speed, sand to acidic solution ratio, acid concentration, temperature and time) for the best performance. The use of reclaimed sand within the foundry would improve the economics and efficiency of the process and reduce environmental concerns.

Keywords: chemical reclamation, clay content, environmental concerns, recycle, waste foundry sand

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4652 Reciprocity and Empathy in Motivating Altruism among Sixth Grade Students

Authors: Rylle Evan Gabriel Zamora, Micah Dennise Malia, Abygail Deniese Villabona

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The primary motivators of altruism are usually viewed as mutually exclusive. In this study, we wanted to know if the two primary motivators, reciprocity and empathy, can work together in motivating altruism. Therefore, we wanted to find out if there is a significant interaction of effects between reciprocity and empathy. To show how this may occur, we devised the combined altruism model, which is based on Batson’s empathy altruism hypothesis. A sample of 120, 6th-grade students were randomly selected and then randomly assigned to four treatment groups. A 2x2 between subjects’ design was used, which had empathy and reciprocity as independent variables, and altruism as the dependent variable. The study made use of materials that were effort based, where subjects were required to complete a task or a puzzle to help a person in a given scenario, two videos, one to prime empathy were also used. This along with Witt & Boleman’s adapted Self-Reported Altruism Scale was used to determine an individual’s altruism. It was found that both variables were significant in motivating altruism, with empathy being the greater of the two. However, there was no significant interaction of effects between the two variables. To explain why this occurred, we turned to the combined altruism model, where it was found that when empathically primed, we tend to not think of ourselves when helping others. Future studies could focus on other variables, especially age which is said to be one of the greatest factors that influenced the results of the experiment.

Keywords: reciprocity, empathy, altruism, experimental psychology, social psychology

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4651 Sensory Characteristics of White Chocolate Enriched with Encapsulated Raspberry Juice

Authors: Ivana Loncarevic, Biljana Pajin, Jovana Petrovic, Danica Zaric, Vesna Tumbas Saponjac, Aleksandar Fistes

Abstract:

Chocolate is a food that activates pleasure centers in the human brain. In comparison to black and milk chocolate, white chocolate does not contain fat-free cocoa solids and thus lacks bioactive components. The aim of this study was to examine the sensory characteristics of enriched white chocolate with the addition of 10% of raspberry juice encapsulated in maltodextrins (denoted as encapsulate). Chocolate is primarily intended for enjoyment, and therefore, the sensory expectation is a critical factor for consumers when selecting a new type of chocolate. Consumer acceptance of chocolate depends primarily on the appearance and taste, but also very much on the mouthfeel, which mainly depends on the particle size of chocolate. Chocolate samples were evaluated by a panel of 8 trained panelists, food technologists, trained according to ISO 8586 (2012). Panelists developed the list of attributes to be used in this study: intensity of red color (light to dark); glow on the surface (mat to shiny); texture on snap (appearance of cavities or holes on the snap surface that are seen - even to gritty); hardness (hardness felt during the first bite of chocolate sample in half by incisors - soft to hard); melting (the time needed to convert solid chocolate into a liquid state – slowly to quickly); smoothness (perception of evenness of chocolate during melting - very even to very granular); fruitiness (impression of fruity taste - light fruity notes to distinct fruity notes); sweetness (organoleptic characteristic of pure substance or mixture giving sweet taste - lightly sweet to very sweet). The chocolate evaluation was carried out 24 h after sample preparation in the sensory laboratory, in partitioned booths, which were illuminated with fluorescent lights (ISO 8589, 2007). Samples were served in white plastic plates labeled with three-digit codes from a random number table. Panelist scored the perceived intensity of each attribute using a 7-point scale (1 = the least intensity and 7 = the most intensity) (ISO 4121, 2002). The addition of 10% of encapsulate had a big influence on chocolate color, where enriched chocolate got a nice reddish color. At the same time, the enriched chocolate sample had less intensity of gloss on the surface. The panelists noticed that addition of encapsulate reduced the time needed to convert solid chocolate into a liquid state, increasing its hardness. The addition of encapsulate had a significant impact on chocolate flavor. It reduced the sweetness of white chocolate and contributed to the fruity raspberry flavor.

Keywords: white chocolate, encapsulated raspberry juice, color, sensory characteristics

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4650 An Approach to Determine the in Transit Vibration to Fresh Produce Using Long Range Radio (LORA) Wireless Transducers

Authors: Indika Fernando, Jiangang Fei, Roger Stanely, Hossein Enshaei

Abstract:

Ever increasing demand for quality fresh produce by the consumers, had increased the gravity on the post-harvest supply chains in multi-fold in the recent years. Mechanical injury to fresh produce was a critical factor for produce wastage, especially with the expansion of supply chains, physically extending to thousands of miles. The impact of vibration damages in transit was identified as a specific area of focus which results in wastage of significant portion of the fresh produce, at times ranging from 10% to 40% in some countries. Several studies were concentrated on quantifying the impact of vibration to fresh produce, and it was a challenge to collect vibration impact data continuously due to the limitations in battery life or the memory capacity in the devices. Therefore, the study samples were limited to a stretch of the transit passage or a limited time of the journey. This may or may not give an accurate understanding of the vibration impacts encountered throughout the transit passage, which limits the accuracy of the results. Consequently, an approach which can extend the capacity and ability of determining vibration signals in the transit passage would contribute to accurately analyze the vibration damage along the post-harvest supply chain. A mechanism was developed to address this challenge, which is capable of measuring the in transit vibration continuously through the transit passage subject to a minimum acceleration threshold (0.1g). A system, consisting six tri-axel vibration transducers installed in different locations inside the cargo (produce) pallets in the truck, transmits vibration signals through LORA (Long Range Radio) technology to a central device installed inside the container. The central device processes and records the vibration signals transmitted by the portable transducers, along with the GPS location. This method enables to utilize power consumption for the portable transducers to maximize the capability of measuring the vibration impacts in the transit passage extending to days in the distribution process. The trial tests conducted using the approach reveals that it is a reliable method to measure and quantify the in transit vibrations along the supply chain. The GPS capability enables to identify the locations in the supply chain where the significant vibration impacts were encountered. This method contributes to determining the causes, susceptibility and intensity of vibration impact damages to fresh produce in the post-harvest supply chain. Extensively, the approach could be used to determine the vibration impacts not limiting to fresh produce, but for products in supply chains, which may extend from few hours to several days in transit.

Keywords: post-harvest, supply chain, wireless transducers, LORA, fresh produce

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4649 Diagenesis of the Permian Ecca Sandstones and Mudstones, in the Eastern Cape Province, South Africa: Implications for the Shale Gas Potential of the Karoo Basin

Authors: Temitope L. Baiyegunhi, Christopher Baiyegunhi, Kuiwu Liu, Oswald Gwavava

Abstract:

Diagenesis is the most important factor that affects or impact the reservoir property. Despite the fact that published data gives a vast amount of information on the geology, sedimentology and lithostratigraphy of the Ecca Group in the Karoo Basin of South Africa, little is known of the diagenesis of the potentially feasible shales and sandstones of the Ecca Group. The study aims to provide a general account of the diagenesis of sandstones and mudstone of the Ecca Group. Twenty-five diagenetic textures and structures are identified and grouped into three regimes or stages that include eogenesis, mesogenesis and telogenesis. Clay minerals are the most common cementing materials in the Ecca sandstones and mudstones. Smectite, kaolinite and illite are the major clay minerals that act as pore lining rims and pore-filling cement. Most of the clay minerals and detrital grains were seriously attacked and replaced by calcite. Calcite precipitates locally in pore spaces and partly or completely replaced feldspar and quartz grains, mostly at their margins. Precipitation of cements and formation of pyrite and authigenic minerals as well as little lithification occurred during the eogenesis. This regime was followed by mesogenesis which brought about an increase in tightness of grain packing, loss of pore spaces and thinning of beds due to weight of overlying sediments and selective dissolution of framework grains. Compaction, mineral overgrowths, mineral replacement, clay-mineral authigenesis, deformation and pressure solution structures occurred during mesogenesis. During rocks were uplifted, weathered and unroofed by erosion, this resulted in additional grain fracturing, decementation and oxidation of iron-rich volcanic fragments and ferromagnesian minerals. The rocks of Ecca Group were subjected to moderate-intense mechanical and chemical compaction during its progressive burial. Intergranular pores, matrix micro pores, secondary intragranular, dissolution and fractured pores are the observed pores. The presence of fractured and dissolution pores tend to enhance reservoir quality. However, the isolated nature of the pores makes them unfavourable producers of hydrocarbons, which at best would require stimulation. The understanding of the space and time distribution of diagenetic processes in these rocks will allow the development of predictive models of their quality, which may contribute to the reduction of risks involved in their exploration.

Keywords: diagenesis, reservoir quality, Ecca Group, Karoo Supergroup

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4648 Environmental Threats and Great Barrier Reef: A Vulnerability Assessment of World’s Best Tropical Marine Ecosystems

Authors: Ravi Kant Anand, Nikkey Keshri

Abstract:

The Great Barrier Reef of Australia is known for its beautiful landscapes and seascapes with ecological importance. This site was selected as a World Heritage site in 1981 and popularized internationally for tourism, recreational activities and fishing. But the major environmental hazards such as climate change, pollution, overfishing and shipping are making worst the site of marine ecosystem. Climate change is directly hitting on Great Barrier Reef through increasing level of sea, acidification of ocean, increasing in temperature, uneven precipitation, changes in the El Nino and increasing level of cyclones and storms. Apart from that pollution is second biggest factor which vanishing the coral reef ecosystem. Pollution including over increasement of pesticides and chemicals, eutrophication, pollution through mining, sediment runoff, loss of coastal wetland and oil spills. Coral bleaching is the biggest problem because of the environmental threatening agents. Acidification of ocean water reduced the formation of calcium carbonate skeleton. The floral ecosystem (including sea grasses and mangroves) of ocean water is the key source of food for fishes and other faunal organisms but the powerful waves, extreme temperature, destructive storms and river run- off causing the threat for them. If one natural system is under threat, it means the whole marine food web is affected from algae to whale. Poisoning of marine water through different polluting agents have been affecting the production of corals, breeding of fishes, weakening of marine health and increased in death of fishes and corals. In lieu of World Heritage site, tourism sector is directly affected and causing increasement in unemployment. Fishing sector also affected. Fluctuation in the temperature of ocean water affects the production of corals because it needs desolate place, proper sunlight and temperature up to 21 degree centigrade. But storms, El Nino, rise in temperature and sea level are induced for continuous reduction of the coral production. If we do not restrict the environmental problems of Great Barrier Reef than the best known ecological beauty with coral reefs, pelagic environments, algal meadows, coasts and estuaries, mangroves forests and sea grasses, fish species, coral gardens and the one of the best tourist spots will lost in upcoming years. My research will focus on the different environmental threats, its socio-economic impacts and different conservative measures.

Keywords: climate change, overfishing, acidification, eutrophication

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4647 Design and Implementation of an Efficient Solar-Powered Pumping System

Authors: Mennatallah M. Fouad, Omar Hussein, Lamia A. Shihata

Abstract:

The main problem in many rural areas is the absence of electricity and limited access to water. The novelty of this work lies in implementing a small-scale experimental setup for a solar-powered water pumping system with a battery back-up system. Cooling and cleaning of the PV panel are implemented to enhance its overall efficiency and output. Moreover, a simulation for a large scale solar-powered pumping system is performed using PVSyst software. Results of the experimental setup show that the PV system with a battery backup proved to be a feasible and viable system to operate the water pumping system. Excess water from the pumping system is used to cool and clean the PV panel and achieved an average percentage increase in the PV output by 21.8%. Simulation results have shown that the system provides adequate output to power the solar-powered system and saves 0.3 tons of CO₂ compared to conventional fossil fuels. It is recommended for hot countries to adopt this system, which would help in decreasing the dependence on the depleting fossil fuels, provide access to electricity to areas where there is no electricity supply and also provide a source of water for crop growth as well as decrease the carbon emissions.

Keywords: efficient solar pumping, PV cleaning, PV cooling, PV-operated water pump

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4646 Effect of Large English Studies Classes on Linguistic Achievement and Classroom Discourse at Junior Secondary Level in Yobe State

Authors: Clifford Irikefe Gbeyonron

Abstract:

Applied linguists concur that there is low-level achievement in English language use among Nigerian secondary school students. One of the factors that exacerbate this is classroom feature of which large class size is obvious. This study investigated the impact of large classes on learning English as a second language (ESL) at junior secondary school (JSS) in Yobe State. To achieve this, Solomon four-group experimental design was used. 382 subjects were divided into four groups and taught ESL for thirteen weeks. 356 subjects wrote the post-test. Data from the systematic observation and post-test were analyzed via chi square and ANOVA. Results indicated that learners in large classes (LLC) attain lower linguistic progress than learners in small classes (LSC). Furthermore, LSC have more chances to access teacher evaluation and participate actively in classroom discourse than LLC. In consequence, large classes have adverse effects on learning ESL in Yobe State. This is inimical to English language education given that each learner of ESL has their individual peculiarity within each class. It is recommended that strategies that prioritize individualization, grouping, use of language teaching aides, and theorization of innovative models in respect of large classes be considered.

Keywords: large classes, achievement, classroom discourse

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4645 The Impact of Teaching Critical Reading Strategies on Students' Performance in English and Communication Skills in College of Education, Azare, Bauchi State Nigeria

Authors: Musa Galadima Toro

Abstract:

The study focused on the impact of teaching critical reading strategies on students’ performance in English and communication skills at the college of education Azare Bauchi state, Nigeria. It adopted a pre-test, post-test experimental group design. A sample of two hundred and forty (240) students was randomly selected from four departments within the school. The students were randomized into two groups: experimental and control groups. The experimental group was taught critical reading strategies as a form of treatment, while the control group involved in normal reading comprehension exercises. The findings of the study showed a significant difference in the performance of students who were taught critical reading strategies at the post- test level. Recommendations based on the findings of the study were proffered such as placing more emphasis on teaching critical reading strategies in order to improve students’ creative thinking skills and also encouraging students to read articles in science and humanities to improve their reading skills among others.

Keywords: English, communication skill, critical reading, strategies

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4644 Design and Characterization of Aromatase Inhibitor Loaded Nanoparticles for the Treatment of Breast Cancer

Authors: Harish K. Chandrawanshi, Mithun S. Rajput, Neelima Choure, Purnima Dey Sarkar, Shailesh Jain

Abstract:

The present research study aimed to fabricate and evaluate biodegradable nanoparticles of aromatase inhibitor letrozole, intended for breast cancer therapy. Letrozole loaded poly(D,L-lactide-co-glycolide acid) nanoparticles were prepared by solvent evaporation method using dichlorometane as solvent (oil phase) and polyvinyl alcohol (PVA) as aqueous phase. Prepared nanoparticles were characterized by particle size, infrared spectra, drug loading efficiency, drug entrapment efficiency and in vitro release and also evaluated for in vivo anticancer activity. The high speed homogenizer was used to produce stable nanoparticles of mean size range 198.35 ± 0.04 nm with high entrapment efficiency (69.86 ± 2.78%). Percentage of drug and homogenization speed significantly influenced the particle size, entrapment efficiency and release (p<0.05). The nanoparticles show significant in vivo anticancer activity against Ehrlich ascites carcinoma in mice. The significant system sustained the release of letrozole drug effectively and further investigation could exhibit its potential usefulness in breast cancer therapy.

Keywords: breast cancer/therapy, letrozole, nanoparticles, PLGA

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4643 An Assessment of the Impact of Safe Motherhood Initiative on Maternal Health of Women in Gumel Local Government Area of Jigawa State, Nigeria

Authors: Ahmed Mudi, Bala Zakar

Abstract:

The paper assesses the impact of safe motherhood initiative on maternal health of women in Gumel Local Government Area of Jigawa State. The work will specifically concentrate on the background on safe motherhood scheme and maternal health of women. The objective of this paper is to assess the level of safe motherhood scheme in Gumel local government area, to find out the level of maternal health in Gumel local government as well as to determine the impact of safe motherhood scheme on maternal health on women in Gumel Local Government Area Jigawa State. Various literature on the topic are reviewed, the paper adopts survey design and use questionnaire to collect data from the respondent. The study comprises 350 women selected from six rural communities in Gumel using random sampling techniques, and the data was analysed by simple frequency and percentage. The research concluded that safe motherhood initiative has a significant impact on the maternal health of women in Gumel Local Government Area of Jigawa State. Finally, suitable recommendations were given on how to improve the scheme to ensure better maternal health in the region.

Keywords: action, assessment, maternal health, safe motherhood, surgery

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4642 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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4641 Conditional Relation between Migration, Demographic Shift and Human Development in India

Authors: Rakesh Mishra, Rajni Singh, Mukunda Upadhyay

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Since the last few decades, the prima facie of development has shifted towards the working population in India. There has been a paradigm shift in the development approach with the realization that the present demographic dividend has to be harnessed for sustainable development. Rapid urbanization and improved socioeconomic characteristics experienced within its territory has catalyzed various forms of migration into it, resulting in massive transference of workforce between its states. Workforce in any country plays a very crucial role in deciding development of both the places, from where they have out-migrated and the place they are residing currently. In India, people are found to be migrating from relatively less developed states to a well urbanized and developed state for satisfying their neediness. Linking migration to HDI at place of destination, the regression coefficient (β ̂) shows affirmative association between them, because higher the HDI of the place would be, higher would be chance of earning and hence likeliness of the migrants would be more to choose that place as a new destination and vice versa. So the push factor is compromised by the cost of rearing and provides negative impulse on the in migrants letting down their numbers to metro cities or megacities of the states but increasing their mobility to the suburban areas and vice versa. The main objective of the study is to check the role of migration in deciding the dividend of the place of destination as well as people at the place of their usual residence with special focus to highly urban states in India. Idealized scenario of Indian migrants refers to some new theories in making. On analyzing the demographic dividend of the places we got to know that Uttar Pradesh provides maximum dividend to Maharashtra, West Bengal and Delhi, and the demographic divided of migrants are quite comparable to the native’s shares in the demographic dividend in these places. On analyzing the data from National Sample Survey 64th round and Census of India-2001, we have observed that for males in rural areas, the share of unemployed person declined by 9 percentage points (from 45% before migration to 36 % after migration) and for females in rural areas the decline was nearly 12 percentage points (from 79% before migration to 67% after migration. It has been observed that the shares of unemployed males in both rural and urban areas, which were significant before migration, got reduced after migration while the share of unemployed females in the rural as well as in the urban areas remained almost negligible both for before and after migration. So increase in the number of employed after migration provides an indication of changes in the associated cofactors like health and education of the place of destination and arithmetically to the place from where they have migrated out. This paper presents the evidence on the patterns of prevailing migration dynamics and corresponding demographic benefits in India and its states, examines trends and effects, and discusses plausible explanations.

Keywords: migration, demographic shift, human development index, multilevel analysis

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4640 Analytical Comparison of Conventional Algorithms with Vedic Algorithm for Digital Multiplier

Authors: Akhilesh G. Naik, Dipankar Pal

Abstract:

In today’s scenario, the complexity of digital signal processing (DSP) applications and various microcontroller architectures have been increasing to such an extent that the traditional approaches to multiplier design in most processors are becoming outdated for being comparatively slow. Modern processing applications require suitable pipelined approaches, and therefore, algorithms that are friendlier with pipelined architectures. Traditional algorithms like Wallace Tree, Radix-4 Booth, Radix-8 Booth, Dadda architectures have been proven to be comparatively slow for pipelined architectures. These architectures, therefore, need to be optimized or combined with other architectures amongst them to enhance its performances and to be made suitable for pipelined hardware/architectures. Recently, Vedic algorithm mathematically has proven to be efficient by appearing to be less complex and with fewer steps for its output establishment and have assumed renewed importance. This paper describes and shows how the Vedic algorithm can be better suited for pipelined architectures and also can be combined with traditional architectures and algorithms for enhancing its ability even further. In this paper, we also established that for complex applications on DSP and other microcontroller architectures, using Vedic approach for multiplication proves to be the best available and efficient option.

Keywords: Wallace Tree, Radix-4 Booth, Radix-8 Booth, Dadda, Vedic, Single-Stage Karatsuba (SSK), Looped Karatsuba (LK)

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4639 Biocompatibility Tests for Chronic Application of Sieve-Type Neural Electrodes in Rats

Authors: Jeong-Hyun Hong, Wonsuk Choi, Hyungdal Park, Jinseok Kim, Junesun Kim

Abstract:

Identifying the chronic functions of an implanted neural electrode is an important factor in acquiring neural signals through the electrode or restoring the nerve functions after peripheral nerve injury. The purpose of this study was to investigate the biocompatibility of the chronic implanted neural electrode into the sciatic nerve. To do this, a sieve-type neural electrode was implanted at proximal and distal ends of a transected sciatic nerve as an experimental group (Sieve group, n=6), and the end-to-end epineural repair was operated with the cut sciatic nerve as a control group (reconstruction group, n=6). All surgeries were performed on the sciatic nerve of the right leg in Sprague Dawley rats. Behavioral tests were performed before and 1, 4, 7, 10, 14, and weekly days until 5 months following surgery. Changes in sensory function were assessed by measuring paw withdrawal responses to mechanical and cold stimuli. Motor function was assessed by motion analysis using a Qualisys program, which showed a range of motion (ROM) related to the joints. Neurofilament-heavy chain and fibronectin expression were detected 5 months after surgery. In both groups, the paw withdrawal response to mechanical stimuli was slightly decreased from 3 weeks after surgery and then significantly decreased at 6 weeks after surgery. The paw withdrawal response to cold stimuli was increased from 4 days following surgery in both groups and began to decrease from 6 weeks after surgery. The ROM of the ankle joint was showed a similar pattern in both groups. There was significantly increased from 1 day after surgery and then decreased from 4 days after surgery. Neurofilament-heavy chain expression was observed throughout the entire sciatic nerve tissues in both groups. Especially, the sieve group was showed several neurofilaments that passed through the channels of the sieve-type neural electrode. In the reconstruction group, however, a suture line was seen through neurofilament-heavy chain expression up to 5 months following surgery. In the reconstruction group, fibronectin was detected throughout the sciatic nerve. However, in the sieve group, the fibronectin was observed only in the surrounding nervous tissues of an implanted neural electrode. The present results demonstrated that the implanted sieve-type neural electrode induced a focal inflammatory response. However, the chronic implanted sieve-type neural electrodes did not cause any further inflammatory response following peripheral nerve injury, suggesting the possibility of the chronic application of the sieve-type neural electrodes. This work was supported by the Basic Science Research Program funded by the Ministry of Science (2016R1D1A1B03933986), and by the convergence technology development program for bionic arm (2017M3C1B2085303).

Keywords: biocompatibility, motor functions, neural electrodes, peripheral nerve injury, sensory functions

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4638 Design and Characterization of a Smart Composite Fabric for Knee Brace

Authors: Rohith J. K., Amir Nazemi, Abbas S. Milani

Abstract:

In Paralympic sports, athletes often depend on some form of equipment to enable competitive sporting, where most of this equipment would only allow passive physiological supports and discrete physiological measurements. Active feedback physiological support and continuous detection of performance indicators, without time or space constraints, would be beneficial in more effective training and performance measures of Paralympic athletes. Moreover, occasionally the athletes suffer from fatigue and muscular stains due to improper monitoring systems. The latter challenges can be overcome by using Smart Composites technology when manufacturing, e.g., knee brace and other sports wearables utilities, where the sensors can be fused together into the fabric and an assisted system actively support the athlete. This paper shows how different sensing functionality may be created by intrinsic and extrinsic modifications onto different types of composite fabrics, depending on the level of integration and the employed functional elements. Results demonstrate that fabric sensors can be well-tailored to measure muscular strain and be used in the fabrication of a smart knee brace as a sample potential application. Materials, connectors, fabric circuits, interconnects, encapsulation and fabrication methods associated with such smart fabric technologies prove to be customizable and versatile.

Keywords: smart composites, sensors, smart fabrics, knee brace

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4637 Infinite Impulse Response Digital Filters Design

Authors: Phuoc Si Nguyen

Abstract:

Infinite impulse response (IIR) filters can be designed from an analogue low pass prototype by using frequency transformation in the s-domain and bilinear z-transformation with pre-warping frequency; this method is known as frequency transformation from the s-domain to the z-domain. This paper will introduce a new method to transform an IIR digital filter to another type of IIR digital filter (low pass, high pass, band pass, band stop or narrow band) using a technique based on inverse bilinear z-transformation and inverse matrices. First, a matrix equation is derived from inverse bilinear z-transformation and Pascal’s triangle. This Low Pass Digital to Digital Filter Pascal Matrix Equation is used to transform a low pass digital filter to other digital filter types. From this equation and the inverse matrix, a Digital to Digital Filter Pascal Matrix Equation can be derived that is able to transform any IIR digital filter. This paper will also introduce some specific matrices to replace the inverse matrix, which is difficult to determine due to the larger size of the matrix in the current method. This will make computing and hand calculation easier when transforming from one IIR digital filter to another in the digital domain.

Keywords: bilinear z-transformation, frequency transformation, inverse bilinear z-transformation, IIR digital filters

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4636 Rethinking Military Aid to Civil Authorities for Internal Security Operations: A Sustainable Solution to Rebuilding Civil Military Relations in Nigeria

Authors: Emmanuela Ngozi Maduka

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In Nigeria, civil-military relations is at its lowest point as a result of the challenges emanating from incessant initiation of military aid to civil authorities (MACA) for internal security operations. This paper is concerned with the question whether it is appropriate for the military to handle internal security crisis with exception to terrorism and armed militia. It analyses the legal framework for MACA in internal security operations which appear to be in contradiction with military tactical and equipment training. The paper argues that the expectation that transitional re-training of the military for internal security operations will reconcile these inconsistencies specifically on the issue of use of force is not practicable and will always pose challenges for both the military and the citizens. Accordingly, this paper adopts a socio-legal methodology for better clarity on the interactions between the legal framework on MACA and military internal security operations. The paper also identifies the lack of effective and proficient paramilitary within the security design of Nigeria as the key issue which results in incessant initiation of MACA and advocates for the establishment of an effective and proficient paramilitary to effectively handle internal security crisis within Nigeria.

Keywords: civil-military relations, MACA, military training, operational challenges, paramilitary, use of force

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4635 Design, Optimize the Damping System for Optical Scanning Equipment

Authors: Duy Nhat Tran, Van Tien Pham, Quang Trung Trinh, Tien Hai Tran, Van Cong Bui

Abstract:

In recent years, artificial intelligence and the Internet of Things have experienced significant advancements. Collecting image data and real-time analysis and processing of tasks have become increasingly popular in various aspects of life. Optical scanning devices are widely used to observe and analyze different environments, whether fixed outdoors, mounted on mobile devices, or used in unmanned aerial vehicles. As a result, the interaction between the physical environment and these devices has become more critical in terms of safety. Two commonly used methods for addressing these challenges are active and passive approaches. Each method has its advantages and disadvantages, but combining both methods can lead to higher efficiency. One solution is to utilize direct-drive motors for position control and real-time feedback within the operational range to determine appropriate control parameters with high precision. If the maximum motor torque is smaller than the inertial torque and the rotor reaches the operational limit, the spring system absorbs the impact force. Numerous experiments have been conducted to demonstrate the effectiveness of device protection during operation.

Keywords: optical device, collision safety, collision absorption, precise mechanics

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4634 Negotiating Sovereign Debt and Human Rights: A Cross Cultural Study

Authors: Prajwal Raj Gyawali, Aastha Dahal

Abstract:

The tension between human rights and loans provided by international development banks with hidden conditions in the pretext of development is a complex issue with significant implications for the rights of citizens in borrowing countries. It is important for all parties involved, including international banks, borrowing countries, and affected communities, to consider and respect human rights in the negotiation and implementation of development projects. Yet, it is rare for human rights actors or communities to have a seat at the negotiation table when loans are finalized. In our research, we conducted negotiation simulations in law schools to examine how international loan negotiations would play out if human rights actors and communities had seats at the table. We ran the negotiation simulations in Bangladesh, Nepal and India. We found that the presence of community groups and human rights actors makes a difference in loan outcomes. While the international development loan was accepted as opposed to rejected by negotiators in three countries, the cultural values of the respective countries played a significant part in terms of the final agreement. We present the findings and their implications for the design of human rights courses in law schools as well as larger policy implications for expanding the participation of actors in international development loan negotiations.

Keywords: law, development, debt, human rights

Procedia PDF Downloads 49
4633 Increased Envy and Schadenfreude in Parents of Newborns

Authors: Ana-María Gómez-Carvajal, Hernando Santamaría-García, Mateo Bernal, Mario Valderrama, Daniela Lizarazo, Juliana Restrepo, María Fernanda Barreto, Angélica Parra, Paula Torres, Diana Matallana, Jaime Silva, José Santamaría-García, Sandra Baez

Abstract:

Higher levels of oxytocin are associated with better performance on social cognition tasks. However, higher levels of oxytocin have also been associated with increased levels of envy and schadenfreude. Considering these antecedents, this study aims to explore social emotions (i.e., envy and schadenfreude) and other components of social cognition (i.e. ToM and empathy), in women in the puerperal period and their respective partners, compared to a control group of men and women without children or partners. Control women should be in the luteal phase of the menstrual cycle or taking oral contraceptives as they allow oxytocin levels to remain stable. We selected this population since increased levels of oxytocin are present in both mothers and fathers of newborn babies. Both groups were matched by age, sex, and education level. Twenty-two parents of newborns (11 women, 11 men) and 15 controls (8 women, 7 men) performed an experimental task designed to trigger schadenfreude and envy. In this task, each participant was shown a real-life photograph and a description of two target characters matched in age and gender with the participant. The task comprised two experimental blocks. In the first block, participants read 15 sentences describing fortunate events involving either character. After reading each sentence, participants rated the event in terms of how much envy they felt for the character (1=no envy, 9=extreme envy). In the second block, participants read and reported the intensity of their pleasure (schadenfreude, 1=no pleasure, 9=extreme pleasure) in response to 15 unfortunate events happening to the characters. Five neutral events were included in each block. Moreover, participants were assessed with ToM and empathy tests. Potential confounding variables such as general cognitive functioning, stress levels, hours of sleep and depression symptoms were also measured. Results showed that parents of newborns showed increased levels of envy and schadenfreude. These effects are not explained by any confounding factor. Moreover, no significant differences were found in ToM or empathy tests. Our results offer unprecedented evidence of specific differences in envy and schadenfreude levels in parents of newborns. Our findings support previous studies showing a negative relationship between oxytocin levels and negative social emotions. Further studies should assess the direct relationship between oxytocin levels in parents of newborns and the performance in social emotions tasks.

Keywords: envy, empathy, oxytocin, schadenfreude, social emotions, theory of mind

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4632 Lightweight Hybrid Convolutional and Recurrent Neural Networks for Wearable Sensor Based Human Activity Recognition

Authors: Sonia Perez-Gamboa, Qingquan Sun, Yan Zhang

Abstract:

Non-intrusive sensor-based human activity recognition (HAR) is utilized in a spectrum of applications, including fitness tracking devices, gaming, health care monitoring, and smartphone applications. Deep learning models such as convolutional neural networks (CNNs) and long short term memory (LSTM) recurrent neural networks (RNNs) provide a way to achieve HAR accurately and effectively. In this paper, we design a multi-layer hybrid architecture with CNN and LSTM and explore a variety of multi-layer combinations. Based on the exploration, we present a lightweight, hybrid, and multi-layer model, which can improve the recognition performance by integrating local features and scale-invariant with dependencies of activities. The experimental results demonstrate the efficacy of the proposed model, which can achieve a 94.7% activity recognition rate on a benchmark human activity dataset. This model outperforms traditional machine learning and other deep learning methods. Additionally, our implementation achieves a balance between recognition rate and training time consumption.

Keywords: deep learning, LSTM, CNN, human activity recognition, inertial sensor

Procedia PDF Downloads 131
4631 A Comparison Study of Different Methods Used in the Detection of Giardia lamblia on Fecal Specimen of Children

Authors: Muhammad Farooq Baig

Abstract:

Objective: The purpose of this study was to compare results obtained using a single fecal specimen for O&P examination, direct immunofluorescence assay (DFA), and two conventional staining methods. Design: Hundred and fifty children fecal specimens were collected and examined by each method. The O&P and the DFA were used as the reference method. Setting: The study was performed at the laboratory in the Basic Medical Science Institute JPMC Karachi. Patients or Other Participants: The fecal specimens were collected from children with a suspected Giardia lamblia infection. Main Outcome Measures: The amount of agreement and disagreement between methods.1) Presence of giardiasis in our population. 2) The sensitivity and specificity of each method. Results: There was 45(30%) positive 105 (70%) negative on DFA, 41 (27.4%) positive 109 (72.6%) negative on iodine and 34 (22.6%) positive 116(77.4%) on saline method. The sensitivity and specificity of DFA in comparision to iodine were 92.2%, 92.7% respectively. The sensitivity and specificity of DFA in comparisoin to saline method were 91.2%, 87.9% respectively. The sensitivity of iodine method and saline method in compariosn to DFA were 82.2%, 68.8% respectively. There is mark diffrence in sensitivity of DFA to conventional method. Conclusion: The study supported findings of other investigators who concluded that DFA method have the greater sensitivity. The immunologic methods were more efficient and quicker than the conventional O&P method.

Keywords: direct immunofluorescence assay (DFA), ova and parasite (O&P), Giardia lamblia, children, medical science

Procedia PDF Downloads 397
4630 New Hybrid Process for Converting Small Structural Parts from Metal to CFRP

Authors: Yannick Willemin

Abstract:

Carbon fibre-reinforced plastic (CFRP) offers outstanding value. However, like all materials, CFRP also has its challenges. Many forming processes are largely manual and hard to automate, making it challenging to control repeatability and reproducibility (R&R); they generate significant scrap and are too slow for high-series production; fibre costs are relatively high and subject to supply and cost fluctuations; the supply chain is fragmented; many forms of CFRP are not recyclable, and many materials have yet to be fully characterized for accurate simulation; shelf life and outlife limitations add cost; continuous-fibre forms have design limitations; many materials are brittle; and small and/or thick parts are costly to produce and difficult to automate. A majority of small structural parts are metal due to high CFRP fabrication costs for the small-size class. The fact that CFRP manufacturing processes that produce the highest performance parts also tend to be the slowest and least automated is another reason CFRP parts are generally higher in cost than comparably performing metal parts, which are easier to produce. Fortunately, business is in the midst of a major manufacturing evolution—Industry 4.0— one technology seeing rapid growth is additive manufacturing/3D printing, thanks to new processes and materials, plus an ability to harness Industry 4.0 tools. No longer limited to just prototype parts, metal-additive technologies are used to produce tooling and mold components for high-volume manufacturing, and polymer-additive technologies can incorporate fibres to produce true composites and be used to produce end-use parts with high aesthetics, unmatched complexity, mass customization opportunities, and high mechanical performance. A new hybrid manufacturing process combines the best capabilities of additive—high complexity, low energy usage and waste, 100% traceability, faster to market—and post-consolidation—tight tolerances, high R&R, established materials, and supply chains—technologies. The platform was developed by Zürich-based 9T Labs AG and is called Additive Fusion Technology (AFT). It consists of a design software offering the possibility to determine optimal fibre layup, then exports files back to check predicted performance—plus two pieces of equipment: a 3d-printer—which lays up (near)-net-shape preforms using neat thermoplastic filaments and slit, roll-formed unidirectional carbon fibre-reinforced thermoplastic tapes—and a post-consolidation module—which consolidates then shapes preforms into final parts using a compact compression press fitted with a heating unit and matched metal molds. Matrices—currently including PEKK, PEEK, PA12, and PPS, although nearly any high-quality commercial thermoplastic tapes and filaments can be used—are matched between filaments and tapes to assure excellent bonding. Since thermoplastics are used exclusively, larger assemblies can be produced by bonding or welding together smaller components, and end-of-life parts can be recycled. By combining compression molding with 3D printing, higher part quality with very-low voids and excellent surface finish on A and B sides can be produced. Tight tolerances (min. section thickness=1.5mm, min. section height=0.6mm, min. fibre radius=1.5mm) with high R&R can be cost-competitively held in production volumes of 100 to 10,000 parts/year on a single set of machines.

Keywords: additive manufacturing, composites, thermoplastic, hybrid manufacturing

Procedia PDF Downloads 81
4629 An Exploration of the Experiences of Women in Polygamous Marriages: A Case Study of Matizha Village, Masvingo, Zimbabwe

Authors: Flora Takayindisa, Tsoaledi Thobejane, Thizwilondi Mudau

Abstract:

This study highlights what people in polygamous marriages face on a daily basis. It argues that there are more disadvantages for women in polygamous marriages than their counterparts in monogamous relationships. The study further suggests that the patriarchal power structure seems to take a powerful and effective role on polygamous marriages in our societies, particularly in Zimbabwe where this study took place. The study explored the intricacies of polygamous marriages and how these dominances can be resolved. The research is therefore presented through the ‘lived realities’ of the affected women in polygamous marriages in Gutu District located in Masvingo Province of Zimbabwe. Polygamous marriages are practised in different societies. Some women who are practising a polygamous lifestyle are emotionally and physically abused in their relationships. Evidence also suggests children from polygamous marriages also suffer psychologically when their fathers take other wives. Relationships within the family are very difficult because of the husband’s seeming favouritism for one wife. Children are mostly affected by disputes between co-wives and they often lack quality time with their fathers. There are mixed feelings about polygamous marriages. There are some people who condemn it saying inhumane. However, considerations must be made of what it might mean to other people who do not have choices of any other form of marriage. The other factor that has to be noted is that polygamous marriages are not always negative. There are some positive things that result from the polygamous marriages. The study was conducted in a village called Matizha. In the study, a qualitative research approach was employed to stimulate awareness of the social, cultural, religious and the effect of economic factors in polygamous marriages. This approach facilitates a unique understanding of the experiences of women in polygamous marriages, their experiences being both negative and positive. The qualitative type of research method enabled the respondents to have an open minded when they were being asked questions. The researcher utilised the feminist theory in the study. The researcher employed guide interviews to acquire information from the participants. The chapter focuses on the participants who took part in the study, how the participants were selected, ethical considerations, data collection, the interview process, the research instruments and the summary. The data was obtained using a guided interview for all the respondents ranging from all ages who are in polygamous marriages. The researcher presented the demographic information of the participants. Thereafter, the researcher presented other aspects of the data collection like social factors, economic factors and also religious affiliation. The conclusions and recommendations are made from the four main themes that came up from the discussions. The recommendations were made for the women, the policies and laws affecting women, and finally, recommendations for future research. It is believed that the overall objectives of the study have been met and research questions have been answered based on the findings of the study discussed.

Keywords: co-wives, egalitarianism, experiences, polyandry, polygamy, woman

Procedia PDF Downloads 244
4628 Facial Design of Combined Photoelectrocehmcial-Fenton Coupling Nanocomposites for Antibiotic Eliminations

Authors: Xinyong Li

Abstract:

A new coupling system was constructed by combining photo-electrochemical cell with eletro-fenton cell (PEC-EF). The electrode material in this system was derived from MnyFe₁₋yCo Prussian-Blue-Analog (PBA). Mn₀.₄Fe₀.₆Co₀.₆₇-N@C spin-coated on carbon paper behaved as the gas diffusion cathode and Mn₀.₄Fe₀.₆Co₀.₆₇O₂.₂ spin-coated on fluorine-tin oxide glass (FTO) as anode. The two separated cells could degrade Sulfamethoxazole (SMX) simultaneously and some coupling mechanisms by PEC and EF enhancing the degradation efficiency were investigated. The continuous on-site generation of H₂O₂ at cathode through an oxygen reduction reaction (ORR) was realized over rotating ring-disk electrode (RRDE). The electron transfer number (n) of the ORR with Mn₀.₄Fe₀.₆Co₀.₆₇-N@C was 2.5 in the selected potential and pH range. The photo-electrochemical properties of Mn₀.₄Fe₀.₆Co₀.₆₇O₂.₂ were systematically studied, which displayed good response towards visible light. The photo-induced electrons at anode can transfer to cathode for further use. Efficient photo-electro-catalytic performance was observed in degrading SMX. Almost 100% SMX removal was achieved in 120 min. This work not only provided a highly effective technique for antibiotic treatment but also revealed the synergic effect between PEC and EF.

Keywords: Electro-Fenton, photo-electrochemical, synergic effect, sulfamethoxazole

Procedia PDF Downloads 129
4627 Second Language Skill through M-Learning

Authors: Subramaniam Chandran, A. Geetha

Abstract:

This paper addresses three issues: how to prepare the instructional design for imparting English language skill from inter-disciplinary self-learning material; how the disadvantaged students are benefited from such kind of language skill imparted through m-learning; and how do m-learners perform better than the other learners. This paper examines these issues through an experimental study conducted among the distance learners enrolled in a preparatory program for bachelor’s degree. This program is designed for the disadvantaged learners especially for the school drop-outs to qualify to pursue graduate program through distant education. It also explains how mobile learning helps them to enhance their capacity in learning despite their rural background and other disadvantages. In India, nearly half of the students enrolled in schools do not complete their study. The pursuance of higher education is very low when compared with developed countries. This study finds a significant increase in their learning capacity and mobile learning seems to be a viable alternative where the conventional system could not reach the disadvantaged learners. Improving the English language skill is one of the reasons for such kind of performance. Exercises framed from the relevant self-learning material for enhancing English language skill not only improves language skill but also widens the subject-knowledge. This paper explains these issues out of the study conducted among the disadvantaged learners.

Keywords: English language skill, disadvantaged learners, distance education, m-learning

Procedia PDF Downloads 407
4626 Development of Anti-Fouling Surface Features Bioinspired by the Patterned Micro-Textures of the Scophthalmus rhombus (Brill)

Authors: Ivan Maguire, Alan Barrett, Alex Forte, Sandra Kwiatkowska, Rohit Mishra, Jens Ducrèe, Fiona Regan

Abstract:

Biofouling is defined as the gradual accumulation of Biomimetics refers to the use and imitation of principles copied from nature. Biomimetics has found interest across many commercial disciplines. Among many biological objects and their functions, aquatic animals deserve a special attention due to their antimicrobial capabilities resulting from chemical composition, surface topography or other behavioural defences, which can be used as an inspiration for antifouling technology. Marine biofouling has detrimental effects on seagoing vessels, both commercial and leisure, as well as on oceanographic sensors, offshore drilling rigs, and aquaculture installations. Sensor optics, membranes, housings and platforms can become fouled leading to problems with sensor performance and data integrity. While many anti-fouling solutions are currently being investigated as a cost-cutting measure, biofouling settlement may also be prevented by creating a surface that does not satisfy the settlement conditions. Brill (Scophthalmus rhombus) is a small flatfish occurring in marine waters of Mediterranean as well as Norway and Iceland. It inhabits sandy and muddy coastal waters from 5 to 80 meters. Its skin colour changes depending on environment, but generally is brownish with light and dark freckles, with creamy underside. Brill is oval in shape and its flesh is white. The aim of this study is to translate the unique micro-topography of the brill scale, to design marine inspired biomimetic surface coating and test it against a typical fouling organism. Following extensive study of scale topography of the brill fish (Scophthalmus rhombus) and the settlement behaviour of the diatom species Psammodictyon sp. via SEM, two state-of-the-art antifouling surface solutions were designed and investigated; A brill fish scale bioinspired surface pattern platform (BFD), and generic and uniformly-arrayed, circular micropillar platform (MPD), with offsets based on diatom species settlement behaviour. The BFD approach consists of different ~5 μm by ~90 μm Brill-replica patterns, grown to a 5 μm height, in a linear array pattern. The MPD approach utilises hexagonal-packed cylindrical pillars 10.6 μm in diameter, grown to a height of 5 μm, with vertical offset of 15 μm and horizontal offset of 26.6 μm. Photolithography was employed for microstructure growth, with a polydimethylsiloxane (PDMS) chip-based used as a testbed for diatom adhesion on both platforms. Settlement and adhesion tests were performed using this PDMS microfluidic chip through subjugation to centrifugal force via an in-house developed ‘spin-stand’ which features a motor, in combination with a high-resolution camera, for real-time observing diatom release from PDMS material. Diatom adhesion strength can therefore be determined based on the centrifugal force generated at varying rotational speeds. It is hoped that both the replica and bio-inspired solutions will give comparable anti-fouling results to these synthetic surfaces, whilst also assisting in determining whether anti-fouling solutions should predominantly be investigating either fully bioreplica-based, or a bioinspired, synthetically-based design.

Keywords: anti-fouling applications, bio-inspired microstructures, centrifugal microfluidics, surface modification

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4625 The Effect of Supplementary Cementitious Materials on Fresh and Hardened Properties of Self-Compacting Concretes

Authors: Akram Salah Eddine Belaidi, Said Kenai, El-Hadj Kadri, Benchaâ Benabed, Hamza Soualhi

Abstract:

Self-compacting concrete (SCC) was developed in the middle of the 1980’s in Japan. SCC flows alone under its dead weight and consolidates itself without any entry of additional compaction energy and without segregation. As an integral part of a SCC, self-compacting mortars (SCM) may serve as a basis for the mix design of concrete since the measurement of the rheological properties of SCCs. This paper discusses the effect of using natural pozzolana (PZ) and marble powder (MP) in two alternative systems ratios PZ/MP = 1 and 1/3 of the performance of the SCC. A total of 11 SCC’s were prepared having a constant water-binder (w/b) ratio of 0.40 and total cementitious materials content of 475 kg/m3. Then, the fresh properties of the mortars were tested for mini-slump flow diameter and mini-V-funnel flow time for SCMs and Slumps flow test, L-Box height ratio, V-Funnel flow time and sieve stability for SCC. Moreover, the development in the compressive strength was determined at 3, 7, 28, 56, and 90 days. Test results have shown that using of ternary blends improved the fresh properties of the mixtures. The compressive strength of SCC at 90 days with 30% of PZ and MP was similar to those of ordinary concrete use in situ.

Keywords: self-compacting mortar, self-compacting concrete, natural pozzolana, marble powder, rheology, compressive strength

Procedia PDF Downloads 357