Search results for: frequency droop control
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14273

Search results for: frequency droop control

6833 Application of Scoring Rubrics by Lecturers towards Objective Assessment of Essay Questions in the Department of Social Science Education, University of Calabar, Nigeria

Authors: Donald B. Enu, Clement O. Ukpor, Abigail E. Okon

Abstract:

Unreliable scoring of students’ performance by lecturers short-chains students’ assessment in terms of underequipping the school authority with facts as intended by society through the curriculum hence, the learners, the school and the society are cheated because the usefulness of testing is defeated. This study, therefore, examined lecturers’ scoring objectivity of essay items in the Department of Social Science Education, University of Calabar, Nigeria. Specifically, it assessed lecturers’ perception of the relevance of scoring rubrics and its level of application. Data were collected from all the 36 lecturers in the Department (28 members and 8 non-members adjourned to the department), through a 20-item questionnaire and checklist instruments. A case-study design was adopted. Descriptive statistics of frequency counts, weighted means, standard deviations, and percentages were used to analyze data gathered. A mean score of 2.5 and or 60 percent and above formed the acceptance or significant level in decision taking. It was found that lecturers perceived the use of scoring rubrics as a relevant practice to ensure fairness and reliable treatment of examiners scripts particularly in marking essay items and that there is a moderately high level of adherence to the application of scoring rubrics. It was also observed that some criteria necessary for the scoring objectivity of essay items were not fully put in place in the department. It was recommended strongly that students’ identities be hidden while marking and that pre-determined marking scheme should be prepared centrally and strictly adhered to during marking and recording of scores. Conference marking should be enforced in the department.

Keywords: essay items, objective scoring, scorers reliability, scoring rubrics

Procedia PDF Downloads 186
6832 Execution of Joinery in Large Scale Projects: Middle East Region as a Case Study

Authors: Arsany Philip Fawzy

Abstract:

This study is going to address the hurdles of project management in the joinery field. It is widely divided into two sections; the first one will shed light on how to execute large-scale projects with a specific focus on the middle east region. It will also raise major obstacles that may face the joinery team from the site clearance and the coordination between the joinery team and the construction team. The second section is going to technically analyze the commercial side of the joinery and how to control the main cost of the project to avoid financial problems. It will also suggest empirical solutions to monitor the cost impact (e.g., Variation of contract quantity and claims).

Keywords: clearance, quality, cost, variation, claim

Procedia PDF Downloads 106
6831 Affectness of Emotional Intelligence on Employee Profesionalism

Authors: Vanisa Damayanti Yuningsih

Abstract:

Employee professionalism is certainly the hope for every company to create a good working environment. Emotional intelligence is one of the factors that determine the success of professionalism, for, in emotional intelligence, an employee can control his ego and can understand and understand his coworkers and thus create a dynamic environment in which to work. Each employee is encouraged to have professionalism in order to optimize his resources. This professionalism is shown by employees being able to do their work and taking responsibility in their profession by involving controlled feelings and emotions. The problem which is drawn from this research is how emotional intelligence can affect the professional attitudes of employees. The purpose of this research is to find out how far emotional intelligence goes in the professional manner of employees.

Keywords: professionalism, emotional intelligence, work environment, company

Procedia PDF Downloads 167
6830 Invasive Asian Carp Fish Species: A Natural and Sustainable Source of Methionine for Organic Poultry Production

Authors: Komala Arsi, Ann M. Donoghue, Dan J. Donoghue

Abstract:

Methionine is an essential dietary amino acid necessary to promote growth and health of poultry. Synthetic methionine is commonly used as a supplement in conventional poultry diets and is temporarily allowed in organic poultry feed for lack of natural and organically approved sources of methionine. It has been a challenge to find a natural, sustainable and cost-effective source for methionine which reiterates the pressing need to explore potential alternatives of methionine for organic poultry production. Fish have high concentrations of methionine, but wild-caught fish are expensive and adversely impact wild fish populations. Asian carp (AC) is an invasive species and its utilization has the potential to be used as a natural methionine source. However, to our best knowledge, there is no proven technology to utilize this fish as a methionine source. In this study, we co-extruded Asian carp and soybean meal to form a dry-extruded, methionine-rich AC meal. In order to formulate rations with the novel extruded carp meal, the product was tested on cecectomized roosters for its amino acid digestibility and total metabolizable energy (TMEn). Excreta was collected and the gross energy, protein content of the feces was determined to calculate Total Metabolizable Energy (TME). The methionine content, digestibility and TME values were greater for the extruded AC meal than control diets. Carp meal was subsequently tested as a methionine source in feeds formulated for broilers, and production performance (body weight gain and feed conversion ratio) was assessed in comparison with broilers fed standard commercial diets supplemented with synthetic methionine. In this study, broiler chickens were fed either a control diet with synthetic methionine or a treatment diet with extruded AC meal (8 replicates/treatment; n=30 birds/replicate) from day 1 to 42 days of age. At the end of the trial, data for body weights, feed intake and feed conversion ratio (FCR) was analyzed using one-way ANOVA with Fisher LSD test for multiple comparisons. Results revealed that birds on AC diet had body weight gains and feed intake comparable to diets containing synthetic methionine (P > 0.05). Results from the study suggest that invasive AC-derived fish meal could potentially be an effective and inexpensive source of sustainable natural methionine for organic poultry farmers.

Keywords: Asian carp, methionine, organic, poultry

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6829 On the Qarat Kibrit Salt Dome Faulting System South of Adam, Oman: In Search of Uranium Anomalies

Authors: Alaeddin Ebrahimi, Narasimman Sundararajan, Bernhard Pracejus

Abstract:

Development of salt domes, often a rising from depths of some 10 km or more, causes an intense faulting of the surrounding host rocks (salt tectonics). The fractured rocks then present ideal space for oil that can migrate and get trapped. If such moving of hydrocarbons passes uranium-carrying rock units (e.g., shales), uranium is collected and enriched by organic carbon compounds. Brines from the salt body are also ideal carriers for oxidized uranium species and will further dislocate uranium when in contact with uranium-enriched oils. Uranium then has the potential to mineralize in the vicinity of the dome (blue halite is evidence for radiation having affected salt deposits elsewhere in the world). Based on this knowledge, the Qarat Kibrit salt dome was investigated by a well-established geophysical method like very low frequency electromagnetic (VLF-EM) along five traverses approximately 250 m in length (10 m intervals) in order to identify subsurface fault systems. In-phase and quadrature components of the VLF-EM signal were recorded at two different transmitter frequencies (24.0 and 24.9 kHz). The images of Fraser filtered response of the in-phase components indicate a conductive zone (fault) in the southeast and southwest of the study area. The Karous-Hjelt current density pseudo section delineates subsurface faults at depths between 10 and 40 m. The stacked profiles of the Fraser filtered responses brought out two plausible trends/directions of faults. However, there seems to be no evidence for uranium enrichment has been recorded in this area.

Keywords: salt dome, uranium, fault, in-phase component, quadrature component, Fraser filter, Karous-Hjelt current density

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6828 Effect of Several Soil Amendments on Water Quality in Mine Soils: Leaching Columns

Authors: Carmela Monterroso, Marc Romero-Estonllo, Carlos Pascual, Beatriz Rodríguez-Garrido

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The mobilization of heavy metals from polluted soils causes their transfer to natural waters, with consequences for ecosystems and human health. Phytostabilization techniques are applied to reduce this mobility, through the establishment of a vegetal cover and the application of soil amendments. In this work, the capacity of different organic amendments to improve water quality and reduce the mobility of metals in mine-tailings was evaluated. A field pilot test was carried out with leaching columns installed on an old Cu mine ore (NW of Spain) which forms part of the PhytoSUDOE network of phytomanaged contaminated field sites (PhytoSUDOE/ Phy2SUDOE Projects (SOE1/P5/E0189 and SOE4/P5/E1021)). Ten columns (1 meter high by 25 cm in diameter) were packed with untreated mine tailings (control) or those treated with organic amendments. Applied amendments were based on different combinations of municipal wastes, bark chippings, biomass fly ash, and nanoparticles like aluminum oxides or ferrihydrite-type iron oxides. During the packing of the columns, rhizon-samplers were installed at different heights (10, 20, and 50 cm) from the top, and pore water samples were obtained by suction. Additionally, in each column, a bottom leachate sample was collected through a valve installed at the bottom of the column. After packing, the columns were sown with grasses. Water samples were analyzed for: pH and redox potential, using combined electrodes; salinity by conductivity meter: bicarbonate by titration, sulfate, nitrate, and chloride, by ion chromatography (Dionex 2000); phosphate by colorimetry with ammonium molybdate/ascorbic acid; Ca, Mg, Fe, Al, Mn, Zn, Cu, Cd, and Pb by flame atomic absorption/emission spectrometry (Perkin Elmer). Porewater and leachate from the control columns (packed with unamended mine tailings) were extremely acidic and had a high concentration of Al, Fe, and Cu. In these columns, no plant development was observed. The application of organic amendments improved soil conditions, which allowed the establishment of a dense cover of grasses in the rest of the columns. The combined effect of soil amendment and plant growth had a positive impact on water quality and reduced mobility of aluminum and heavy metals.

Keywords: leaching, organic amendments, phytostabilization, polluted soils

Procedia PDF Downloads 117
6827 Irregular Meal Pattern: What Is the Impact on Weight

Authors: Maha Alhussain, Moira A Taylor, Ian A. Macdonald

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Background: It is well established that dietary composition has effects on metabolism and therefore impacts on health; however other aspects of diet, such as meal pattern, could also be important in both obesity management and promoting health. The present study investigated the effect of irregular meal frequency on anthropometric measurements and energy expenditure (EE) in healthy women. Design: 11 healthy weight women (18–40 years) were studied in a randomized crossover trial with two phases of 2 weeks each. In Phase 1, participants consumed either a regular meal pattern (6 meals/day) or an irregular meal pattern (varying from 3 to 9 meals/day). In Phase 2, participants followed the alternative meal pattern to that followed in Phase 1, after a 2-weeks washout period. In the two phases, identical foods were provided to a participant in amounts designed to keep body weight constant. Participants came to the laboratory after an overnight fast at the start and end of each phase. EE was measured in fasting state by indirect calorimetry. Postprandial EE was measured during the 3 h period after consumption of a milkshake, test drink. Results: There were no significant changes in body weight and anthropometric measurements after both meal pattern interventions. There was also no significant difference in mean daily energy intake between the regular and irregular meal pattern (2043 ±31 and 2099 ±33 respectively). EE in the fasting state showed no significant differences cross the experiment visits. There was a significant difference in Postprandial EE (measured for 3 h) by visit (P=0.04). Postprandial EE after the regular meal pattern was significantly higher than at baseline (P=0.002) or than after the irregular meal pattern (P= 0.04). Conclusion: Eating regularly for 14-day period significantly increases Postprandial EE which may contribute to weight loss and obesity management.

Keywords: energy expenditure, energy intake, meal pattern, weight loss

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6826 Impacts of Hydrologic and Topographic Changes on Water Regime Evolution of Poyang Lake, China

Authors: Feng Huang, Carlos G. Ochoa, Haitao Zhao

Abstract:

Poyang Lake, the largest freshwater lake in China, is located at the middle-lower reaches of the Yangtze River basin. It has great value in socioeconomic development and is internationally recognized as an important lacustrine and wetland ecosystem with abundant biodiversity. Impacted by ongoing climate change and anthropogenic activities, especially the regulation of the Three Gorges Reservoir since 2003, Poyang Lake has experienced significant water regime evolution, resulting in challenges for the management of water resources and the environment. Quantifying the contribution of hydrologic and topographic changes to water regime alteration is necessary for policymakers to design effective adaption strategies. Long term hydrologic data were collected and the back-propagation neural networks were constructed to simulate the lake water level. The impacts of hydrologic and topographic changes were differentiated through scenario analysis that considered pre-impact and post-impact hydrologic and topographic scenarios. The lake water regime was characterized by hydrologic indicators that describe monthly water level fluctuations, hydrologic features during flood and drought seasons, and frequency and rate of hydrologic variations. The results revealed different contributions of hydrologic and topographic changes to different features of the lake water regime.Noticeable changes were that the water level declined dramatically during the period of reservoir impoundment, and the drought was enhanced during the dry season. The hydrologic and topographic changes exerted a synergistic effect or antagonistic effect on different lake water regime features. The findings provide scientific reference for lacustrine and wetland ecological protection associated with water regime alterations.

Keywords: back-propagation neural network, scenario analysis, water regime, Poyang Lake

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6825 Inter-Annual Variations of Sea Surface Temperature in the Arabian Sea

Authors: K. S. Sreejith, C. Shaji

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Though both Arabian Sea and its counterpart Bay of Bengal is forced primarily by the semi-annually reversing monsoons, the spatio-temporal variations of surface waters is very strong in the Arabian Sea as compared to the Bay of Bengal. This study focuses on the inter-annual variability of Sea Surface Temperature (SST) in the Arabian Sea by analysing ERSST dataset which covers 152 years of SST (January 1854 to December 2002) based on the ICOADS in situ observations. To capture the dominant SST oscillations and to understand the inter-annual SST variations at various local regions of the Arabian Sea, wavelet analysis was performed on this long time-series SST dataset. This tool is advantageous over other signal analysing tools like Fourier analysis, based on the fact that it unfolds a time-series data (signal) both in frequency and time domain. This technique makes it easier to determine dominant modes of variability and explain how those modes vary in time. The analysis revealed that pentadal SST oscillations predominate at most of the analysed local regions in the Arabian Sea. From the time information of wavelet analysis, it was interpreted that these cold and warm events of large amplitude occurred during the periods 1870-1890, 1890-1910, 1930-1950, 1980-1990 and 1990-2005. SST oscillations with peaks having period of ~ 2-4 years was found to be significant in the central and eastern regions of Arabian Sea. This indicates that the inter-annual SST variation in the Indian Ocean is affected by the El Niño-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) events.

Keywords: Arabian Sea, ICOADS, inter-annual variation, pentadal oscillation, SST, wavelet analysis

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6824 The Causes and Effects of Delinquent Behaviour among Students in Juvenile Home: A Case Study of Osun State

Authors: Baleeqs, O. Adegoke, Adeola, O. Aburime

Abstract:

Juvenile delinquency is fast becoming one of the largest problems facing many societies due to many different factors ranging from parental factors to bullying at schools all which had led to different theoretical notions by different scholars. Delinquency is an illegal or immoral behaviour, especially by the young person who behaves in a way that is illegal or that society does not approve of. The purpose of the study was to investigate causes and effects of delinquent behaviours among adolescent in juvenile home in Osun State. A descriptive survey research type was employed. The random sampling technique was used to select 100 adolescents in Juvenile home in Osun State. Questionnaires were developed and given to them. The data collected from this study were analyzed using frequency counts and percentage for the demographic data in section A, while the two research hypotheses postulated for this study were tested using t-test statistics at the significance level of 0.05. Findings revealed that the greatest school effects of delinquent behaviours among adolescent in juvenile home in Osun by respondents were their aggressive behaviours. Findings revealed that there was a significant difference in the causes and effects of delinquent behaviours among adolescent in juvenile home in Osun State. It was also revealed that there was no significant difference in the causes and effects of delinquent behaviours among secondary school students in Osun based on gender. These recommendations were made in order to address the findings of this study: More number of teachers should be appointed in the observation home so that it will be possible to provide teaching to the different age group of delinquents. Developing the infrastructure facilities of short stay homes and observation home is a top priority. Proper counseling session’s interval is highly essential for these juveniles.

Keywords: behaviour, delinquency, juvenile, random sampling, statistical techniques, survey

Procedia PDF Downloads 198
6823 From the Perspective of a Veterinarian: The Future of Plant Raw Materials Used in the Feeding of Farm Animals

Authors: Ertuğrul Yılmaz

Abstract:

One of the most important occupational groups in the food chain from farm to fork is a veterinary medicine. This occupational group, which has important duties in the prevention of many zoonotic diseases and in public health, takes place in many critical control points from soil to our kitchen. It has important duties from mycotoxins transmitted from the soil to slaughterhouses or milk processing facilities. Starting from the soil, which constitutes 70% of mycotoxin contamination, up to the TMR made from raw materials obtained from the soil, there are all critical control points from feeding to slaughterhouses and milk production enterprises. We can take the precaution of mycotoxins such as Aflatoxin B1, Ochratoxin, Zearalenone, and Fumonisin, which we encounter on farms while in the field. It has been reported that aflatoxin B1 is a casenerogen and passes into milk in studies. It is likely that many mycotoxins pose significant threats to public health and will turn out to be even more dangerous over time. Even raw material storage and TMR preparation are very important for public health. The danger of fumonisin accumulating in the liver will be understood over time. Zoonotic diseases are also explained with examples. In this study, how important veterinarians are in terms of public health is explained with examples. In the two-year mycotoxin screenings, fumonisin mycotoxin was found to be very high in corn and corn by-products, and it was determined that it accumulated in the liver for a long time and remained cornic in animals. It has been determined that mycotoxins are present in all livestock feeds, poultry feeds, and raw materials, not alone, but in double-triple form. Starting from the end, mycotoxin scans should be carried out from feed to raw materials and from raw materials to soil. In this way, we prevent the transmission of mycotoxins to animals and from animals to humans. Liver protectors such as toxin binders, beta-glucan, mannan oligosaccharides, activated carbon, prebiotics, and silymarin were used in certain proportions in the total mixed ratio, and positive results were obtained. Humidity and temperature controls of raw material silos were made at certain intervals. Necropsy was performed on animals that died as a result of mycotoxicosis, and macroscopic photographs were taken of the organs. We have determined that the mycotoxin screening in experimental animals and the feeds made without detecting the presence and amount of bacterial factors affect the results of the project to be made. For this, a series of precautionary plans have been created, starting from the production processes.

Keywords: mycotoxins, feed safety, processes, public health

Procedia PDF Downloads 90
6822 High Volume Fly Ash Concrete for Paver Blocks

Authors: Som Nath Sachdeva, Vanita Aggarwal, S. M. Gupta

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Use of concrete paver blocks is becoming increasingly popular. They are used for paving of approaches, paths and parking areas including their application in pre-engineered buildings. This paper discusses the results of an experimental study conducted on Fly Ash Concrete with the aim to report its suitability for concrete paver blocks. In this study, the effect of varying proportions of fly ash, 20 % to 40 %, on compressive strength and flexural strength of concrete has been evaluated. The mix designs studied are M-30, M-35, M-40 and M-50. It is observed that all the fly ash based mixes are able to achieve the required compressive and flexural strengths. In comparison to control mixes, the compressive and flexural strengths of the fly ash based mixes are found to be slightly less at 7 days and 28 days and a little more at 90 days.

Keywords: fly ash concrete, paver blocks, compressive, flexural strength

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6821 National Image in the Age of Mass Self-Communication: An Analysis of Internet Users' Perception of Portugal

Authors: L. Godinho, N. Teixeira

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Nowadays, massification of Internet access represents one of the major challenges to the traditional powers of the State, among which the power to control its external image. The virtual world has also sparked the interest of social sciences which consider it a new field of study, an immense open text where sense is expressed. In this paper, that immense text has been accessed to so as to understand the perception Internet users from all over the world have of Portugal. Ours is a quantitative and qualitative approach, as we have resorted to buzz, thematic and category analysis. The results confirm the predominance of sea stereotype in others' vision of the Portuguese people, and evidence that national image has adapted to network communication through processes of individuation and paganization.

Keywords: national image, internet, self-communication, perception

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6820 OBD-Biofertilizer Impact on Crop Yield and Soil Quality in Lowland Rice Production, Badeggi, Niger State, Nigeria

Authors: Ayodele A. Otaiku

Abstract:

Purpose: Nigeria has become the largest importer of rice in Africa and second in the world, 2015. Investigate interactions of organic rice farming on soil quality and health from bio-waste converted to biofertilizer and its environmental impact on rice crop. Methodology: Bio-wastes, poultry waste, organic agriculture wastes, wood ash mixed with microbial inoculant organisms called OBD-Plus microbes (broad spectrum) composted in anaerobic digester to OBD-biofertilizer (2010 - 2012) uses microbes to build humus and other stable carbons. Two field experiments were carried out at Badeggi, Niger state in 2011 and 2012 to evaluate the response of lowland rice production using biofertilizer. The experimental field was laid out in a strip-plot design with five treatments and three replications and at twenty-one day old seedlings of FARO 44 and FARO 52 rice varieties were transplanted. Plots without fertiliser application served as control. Findings: The highest rice grain yield increase of 4.4 t/ha over the control in 2012 against the Nigeria average of lowland rice grain yields of 1.5 t/ha. The utilization of OBD-Biofertilizer can decrease the use of chemical nitrogen fertilizer, prevent the depletion of soil organic matter and reduce environmental pollution. Increasing the floodwater productivity and optimizing the recycling of nutrients cum grazer populations and disease by biocontrols microbes present in the OBD-Biofertilizer. Organic matter in the soil improves by 58% and C/N 15 (2011) and 13.35 (2012). Implications: OBD- Biofertilizer produce plant growth hormones such as indole acetic acid (IAA), glomalin related soil protein and extracellular enzymes as phosphatases that promote soil health and quality. Conclusion: Microorganisms can enhance nutrients use efficiency by increasing root surface area e.g., mycorrhizal, fungi, promoting other beneficial symbioses of the host plant and microbial interactions resulting to increase in soil organic matter. By 2030, climate change is projected to depress cereal production in Africa by 2 to 3 percent. Improved seeds and increased fertilizer use should more than compensate, but this factor will still weigh heavily on efforts to make progress.

Keywords: OBD-plus microbial consortia, OBD-biofertilizer, rice production, soil quality, sustainable agriculture

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6819 Long Term Survival after a First Transient Ischemic Attack in England: A Case-Control Study

Authors: Padma Chutoo, Elena Kulinskaya, Ilyas Bakbergenuly, Nicholas Steel, Dmitri Pchejetski

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Transient ischaemic attacks (TIAs) are warning signs for future strokes. TIA patients are at increased risk of stroke and cardio-vascular events after a first episode. A majority of studies on TIA focused on the occurrence of these ancillary events after a TIA. Long-term mortality after TIA received only limited attention. We undertook this study to determine the long-term hazards of all-cause mortality following a first episode of a TIA using anonymised electronic health records (EHRs). We used a retrospective case-control study using electronic primary health care records from The Health Improvement Network (THIN) database. Patients born prior to or in year 1960, resident in England, with a first diagnosis of TIA between January 1986 and January 2017 were matched to three controls on age, sex and general medical practice. The primary outcome was all-cause mortality. The hazards of all-cause mortality were estimated using a time-varying Weibull-Cox survival model which included both scale and shape effects and a random frailty effect of GP practice. 20,633 cases and 58,634 controls were included. Cases aged 39 to 60 years at the first TIA event had the highest hazard ratio (HR) of mortality compared to matched controls (HR = 3.04, 95% CI (2.91 - 3.18)). The HRs for cases aged 61-70 years, 71-76 years and 77+ years were 1.98 (1.55 - 2.30), 1.79 (1.20 - 2.07) and 1.52 (1.15 - 1.97) compared to matched controls. Aspirin provided long-term survival benefits to cases. Cases aged 39-60 years on aspirin had HR of 0.93 (0.84 - 1.00), 0.90 (0.82 - 0.98) and 0.88 (0.80 - 0.96) at 5 years, 10 years and 15 years, respectively, compared to cases in the same age group who were not on antiplatelets. Similar beneficial effects of aspirin were observed in other age groups. There were no significant survival benefits with other antiplatelet options. No survival benefits of antiplatelet drugs were observed in controls. Our study highlights the excess long-term risk of death of TIA patients and cautions that TIA should not be treated as a benign condition. The study further recommends aspirin as the better option for secondary prevention for TIA patients compared to clopidogrel recommended by NICE guidelines. Management of risk factors and treatment strategies should be important challenges to reduce the burden of disease.

Keywords: dual antiplatelet therapy (DAPT), General Practice, Multiple Imputation, The Health Improvement Network(THIN), hazard ratio (HR), Weibull-Cox model

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6818 Improved Performance of AlGaN/GaN HEMTs Using N₂/NH₃ Pretreatment before Passivation

Authors: Yifan Gao

Abstract:

Owing to the high breakdown field, high saturation drift velocity, 2DEG with high density and mobility and so on, AlGaN/GaN HEMTs have been widely used in high-frequency and high-power applications. To acquire a higher power often means higher breakdown voltage and higher drain current. Surface leakage current is usually the key issue affecting the breakdown voltage and power performance. In this work, we have performed in-situ N₂/NH₃ pretreatment before the passivation to suppress the surface leakage and achieve device performance enhancement. The AlGaN/GaN HEMT used in this work was grown on a 3-in. SiC substrate, whose epitaxial structure consists of a 3.5-nm GaN cap layer, a 25-nm Al₀.₂₅GaN barrier layer, a 1-nm AlN layer, a 400-nm i-GaN layer and a buffer layer. In order to analyze the mechanism for the N-based pretreatment, the details are measured by XPS analysis. It is found that the intensity of Ga-O bonds is decreasing and the intensity of Ga-N bonds is increasing, which means with the supplement of N, the dangling bonds on the surface are indeed reduced with the forming of Ga-N bonds, reducing the surface states. The surface states have a great influence on the leakage current, and improved surface states represent a better off-state of the device. After the N-based pretreatment, the breakdown voltage of the device with Lₛ𝒹=6 μm increased from 93V to 170V, which increased by 82.8%. Moreover, for HEMTs with Lₛ𝒹 of 6-μm, we can obtain a peak output power (Pout) of 12.79W/mm, power added efficiency (PAE) of 49.84% and a linear gain of 20.2 dB at 60V under 3.6GHz. Comparing the result with the reference 6-μm device, Pout is increased by 16.5%. Meanwhile, PAE and the linear gain also have a slight increase. The experimental results indicate that using N₂/NH₃ pretreatment before passivation is an attractive approach to achieving power performance enhancement.

Keywords: AlGaN/GaN HEMT, N-based pretreatment, output power, passivation

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6817 Assessment of Climate Change Impact on Meteorological Droughts

Authors: Alireza Nikbakht Shahbazi

Abstract:

There are various factors that affect climate changes; drought is one of those factors. Investigation of efficient methods for estimating climate change impacts on drought should be assumed. The aim of this paper is to investigate climate change impacts on drought in Karoon3 watershed located south-western Iran in the future periods. The atmospheric general circulation models (GCM) data under Intergovernmental Panel on Climate Change (IPCC) scenarios should be used for this purpose. In this study, watershed drought under climate change impacts will be simulated in future periods (2011 to 2099). Standard precipitation index (SPI) as a drought index was selected and calculated using mean monthly precipitation data in Karoon3 watershed. SPI was calculated in 6, 12 and 24 months periods. Statistical analysis on daily precipitation and minimum and maximum daily temperature was performed. LRAS-WG5 was used to determine the feasibility of future period's meteorological data production. Model calibration and verification was performed for the base year (1980-2007). Meteorological data simulation for future periods under General Circulation Models and climate change IPCC scenarios was performed and then the drought status using SPI under climate change effects analyzed. Results showed that differences between monthly maximum and minimum temperature will decrease under climate change and spring precipitation shall increase while summer and autumn rainfall shall decrease. The precipitation occurs mainly between January and May in future periods and summer or autumn precipitation decline and lead up to short term drought in the study region. Normal and wet SPI category is more frequent in B1 and A2 emissions scenarios than A1B.

Keywords: climate change impact, drought severity, drought frequency, Karoon3 watershed

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6816 New Scheme of Control and Air Supply in a Low-Power Hot Water Boiler

Authors: М. Zh. Khazimov, А. B. Kudasheva

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The article presents the state of solid fuel reserves and their share in the world energy sector. The air pollution caused by the operation of heating devices using solid fuels is a significant problem. In order to improve the air quality, heating device producers take constant measures to improve their products. However, the emission results achieved during an initial test of heating devices in the laboratory may be much worse during operation in real operating conditions. The ways of increasing the efficiency of the boiler by improving its design for combustion in full-layer mode are shown. The results of the testing of the improved КВТС-0.2 hot water boiler is presented and the technical and economic indicators are determined, which indicate an increase in the efficiency of the boiler.

Keywords: boiler unit, grate, furnace, coal, ash

Procedia PDF Downloads 74
6815 SAFECARE: Integrated Cyber-Physical Security Solution for Healthcare Critical Infrastructure

Authors: Francesco Lubrano, Fabrizio Bertone, Federico Stirano

Abstract:

Modern societies strongly depend on Critical Infrastructures (CI). Hospitals, power supplies, water supplies, telecommunications are just few examples of CIs that provide vital functions to societies. CIs like hospitals are very complex environments, characterized by a huge number of cyber and physical systems that are becoming increasingly integrated. Ensuring a high level of security within such critical infrastructure requires a deep knowledge of vulnerabilities, threats, and potential attacks that may occur, as well as defence and prevention or mitigation strategies. The possibility to remotely monitor and control almost everything is pushing the adoption of network-connected devices. This implicitly introduces new threats and potential vulnerabilities, posing a risk, especially to those devices connected to the Internet. Modern medical devices used in hospitals are not an exception and are more and more being connected to enhance their functionalities and easing the management. Moreover, hospitals are environments with high flows of people, that are difficult to monitor and can somehow easily have access to the same places used by the staff, potentially creating damages. It is therefore clear that physical and cyber threats should be considered, analysed, and treated together as cyber-physical threats. This means that an integrated approach is required. SAFECARE, an integrated cyber-physical security solution, tries to respond to the presented issues within healthcare infrastructures. The challenge is to bring together the most advanced technologies from the physical and cyber security spheres, to achieve a global optimum for systemic security and for the management of combined cyber and physical threats and incidents and their interconnections. Moreover, potential impacts and cascading effects are evaluated through impact propagation models that rely on modular ontologies and a rule-based engine. Indeed, SAFECARE architecture foresees i) a macroblock related to cyber security field, where innovative tools are deployed to monitor network traffic, systems and medical devices; ii) a physical security macroblock, where video management systems are coupled with access control management, building management systems and innovative AI algorithms to detect behavior anomalies; iii) an integration system that collects all the incoming incidents, simulating their potential cascading effects, providing alerts and updated information regarding assets availability.

Keywords: cyber security, defence strategies, impact propagation, integrated security, physical security

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6814 Efficiently Silicon Metasurfaces at Visible Light

Authors: Juntao Li

Abstract:

The metasurfaces for beam deflecting with gradient silicon posts in the square lattices were fabricated on the thin film crystal silicon with quartz substrate. By using the crystals silicon with high refractive index and high transmission to control the phase over 2π coverage, we demonstrated the polarization independent beam deflecting at wavelength of 532nm with 45% transmission in experiment and 70% in simulation into the desired angle. This simulation efficiency is almost close to the TiO2 metasurfaces but has higher refractive index and lower aspect ratio to reduce fabrication complexity. The result can extend the application of silicon metalsurfaces from 700 nm to 500 nm hence open a new way to use metasurfaces efficiently in visible light regime.

Keywords: metasurfaces, crystal silicon, light deflection, visible light

Procedia PDF Downloads 285
6813 Renal Angiomyolipoma Rupture Following COVID-19 Infection: A Case Report

Authors: Mohammed Abdurabu, Akram Al-Warqi, Ebrahim M. A. Ebrahim, Jouhar Kollari, Salman Mirza

Abstract:

The novel coronavirus (COVID-19) is one of the most recent pandemics that invaded earth that left and still leaving hundreds of thousands of patients and ended with high morbidity and mortality rates with no clear cure till this moment. COVID-19 has been proven to be associated with pathologic changes in coagulation, characterized by either thromboembolic or bleeding events. We present this case of a 44-year-old male patient that presented to our Emergency Department with flank pain that later was found to have renal angiomyolipoma (AML) rupture during his COVID-19 infection, ultimately requiring admission for hemorrhage control via Interventional Radiology (IR) drainage. Here, we discuss the role of the front-line physicians and how they should keep a low threshold for the different presentations that could be associated with COVID-19 infection.

Keywords: angiomyolipoma, COVID-19, renal, rupture

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6812 Reflection Phase Tuning of Graphene Plasmons by Substrate Design

Authors: Xiaojie Jiang, Wei Cai, Yinxiao Xiang, Ni Zhang, Mengxin Ren, Xinzheng Zhang, Jingjun Xu

Abstract:

Reflection phase of graphene plasmons (GPs) at an abrupt interface is very important, which determines the plasmon resonance of graphene structures of deep sub-wavelength scales. However, at an abrupt graphene edge, the reflection phase is always a constant, ΦR ≈ π/4. In this work, we show that the reflection phase of GPs can be efficiently changed through substrate design. Reflection phase of graphene plasmons (GPs) at an abrupt interface is very important, which determines the plasmon resonance of graphene structures of deep sub-wavelength scales. However, at an abrupt graphene edge, the reflection phase is always a constant, ΦR ≈ π/4. In this work, we show that the reflection phase of GPs can be efficiently changed through substrate design. Specifically, the reflection phase is no longer π/4 at the interface formed by placing a graphene sheet on different substrates. Moreover, tailorable reflection phase of GPs up to 2π variation can be further achieved by scattering GPs at a junction consisting of two such dielectric interfaces with various gap width acting as a Fabry-Perot cavity. Besides, the evolution of plasmon mode in graphene ribbons based on the interface reflection phase tuning is predicted, which is expected to be observed in near-field experiments with scattering-type scanning near-field optical microscopy (s-SNOM). Our work provides another way for in-plane plasmon control, which should find applications for integrated plasmon devices design using graphene.Specifically, the reflection phase is no longer π/4 at the interface formed by placing a graphene sheet on different substrates. Moreover, tailorable reflection phase of GPs up to 2π variation can be further achieved by scattering GPs at a junction consisting of two such dielectric interfaces with various gap width acting as a Fabry-Perot cavity. Besides, the evolution of plasmon mode in graphene ribbons based on the interface reflection phase tuning is predicted, which is expected to be observed in near-field experiments with scattering-type scanning near-field optical microscopy (s-SNOM). Our work provides a new way for in-plane plasmon control, which should find applications for integrated plasmon devices design using graphene.

Keywords: graphene plasmons, reflection phase tuning, plasmon mode tuning, Fabry-Perot cavity

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6811 Speech Recognition Performance by Adults: A Proposal for a Battery for Marathi

Authors: S. B. Rathna Kumar, Pranjali A Ujwane, Panchanan Mohanty

Abstract:

The present study aimed to develop a battery for assessing speech recognition performance by adults in Marathi. A total of four word lists were developed by considering word frequency, word familiarity, words in common use, and phonemic balance. Each word list consists of 25 words (15 monosyllabic words in CVC structure and 10 monosyllabic words in CVCV structure). Equivalence analysis and performance-intensity function testing was carried using the four word lists on a total of 150 native speakers of Marathi belonging to different regions of Maharashtra (Vidarbha, Marathwada, Khandesh and Northern Maharashtra, Pune, and Konkan). The subjects were further equally divided into five groups based on above mentioned regions. It was found that there was no significant difference (p > 0.05) in the speech recognition performance between groups for each word list and between word lists for each group. Hence, the four word lists developed were equally difficult for all the groups and can be used interchangeably. The performance-intensity (PI) function curve showed semi-linear function, and the groups’ mean slope of the linear portions of the curve indicated an average linear slope of 4.64%, 4.73%, 4.68%, and 4.85% increase in word recognition score per dB for list 1, list 2, list 3 and list 4 respectively. Although, there is no data available on speech recognition tests for adults in Marathi, most of the findings of the study are in line with the findings of research reports on other languages. The four word lists, thus developed, were found to have sufficient reliability and validity in assessing speech recognition performance by adults in Marathi.

Keywords: speech recognition performance, phonemic balance, equivalence analysis, performance-intensity function testing, reliability, validity

Procedia PDF Downloads 360
6810 The Impact of the Mastering My Mental Fitness™-Nurses Workshops on Practical Nursing Students’ Perceived Burnout and Psychological Capital: An Embedded Mixed Methods Study

Authors: Linda Frost, Lindsay Anderson, Jana Borras, Ariel Dysangco, Vimabayi Makwaira

Abstract:

The academic environment in which nursing students are immersed in comes with many demands and expectations. Course load, clinical placements, and financial expenses are examples of the pressures facing students each semester. These pressures contribute to student stress and impact their overall well-being and mental fitness. Students' ability to cope with stress and bounce back from adversity is enhanced when we build their mental fitness. Building mental fitness has the benefit of improving physical health, relationships, self-esteem, resilience, work productivity, and overall contentment, happiness and life satisfaction. While self-care is encouraged to avoid burnout, there is a gap in literature on programs to help build nursing students’ mental health and ability to engage in self-care. There is an opportunity and a need to design programs and implement actions aimed at reducing stress and its adverse effects on nursing students. Nursing students require the support of people who understand the complexities of the nursing profession, multifaceted work environments in which they operate, and the impact these environments have on their mental fitness. Nursing academia is in the best position to ensure that tools are in place to support the next generation of nurses who face a career with significant emotional and physical demands. This is a mixed-method study using an embedded design. We utilized a pretest-posttest design to compare the difference in psychological capital (PsyCap) and burnout in students who have received the Mastering My Mental Fitness-Nurses™ (MMMF-N™) workshops (n=8) and the control group (n=9) who have not. Semi structured interviews were conducted with the eight nursing students in the intervention group, along with data from feedback forms to explore the impact of the workshops on student’s burnout and PsyCap and determine how to improve the workshops for future students. The quantitative and qualitative data will be merged using a side-by-side comparison. This will be in a discussion format that allows for the comparison of the results from both phases. The findings will be available January 2025. We anticipate that students in the control and intervention group will report similar levels of burnout. As well, students in the intervention group will indicate the benefits of the MMMF-N™ workshops through qualitative interviews and workshop feedback forms.

Keywords: burnout, mental fitness, nursing students, psychological capital

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6809 Dermatological Study on Risk Factors for Pruritic Skin: Skin Properties of Elderly

Authors: Dianis Wulan Sari, Takeo Minematsu, Mikako Yoshida, Hiromi Sanada

Abstract:

Introduction: Pruritus is diagnosed as itching without macroscopic abnormalities on skin. It is the most skin complaint of elderly people. In the present study, we conducted a dermatological study to examine the risk factors of pruritic skin and predicted how to prevent pruritus especially in the elderly population. Pruritus is caused several types of inflammation, including epidermal innate immunity based on keratinocyte responses and acquired immunity regulated by type 1 or 2 helper T (Th) cells. The triggers of pruritus differ among inflammation types, therefore we did separately assess the pruritus-associated factors of each inflammation type in an effort to contribute to the identification of intervention targets for preventing pruritus. Therefore, this study aimed to investigate the factors related with actual condition of pruritic skin by examine the skin properties. Method: This study was conducted in elderly population of Indonesian nursing home. Basic characteristics and behaviors were obtained by interview. The properties of pruritic skin were collected by examination of skin biomarker using skin blotting as novel method of non-invasive skin assessment method and examination of skin barrier function using stratum corneum hydration and skin pH. Result: The average age of participants was 74 years with independent status was 66.8%. Age (β = -0.130, p = 0.044), cumulative lifetime sun exposure (β = 0.145, p = 0.026), bathing duration (β = 0.151, p = 0.022), clothing change frequency (β = 0.135, p = 0.029), and clothing type (β = -0.139, p = 0.021) were risk factors of pruritic skin in multivariate analysis. Conclusion: Risk factors of pruritic skin in elderly population were caused by internal factors such as skin senescence and external factors such as sun exposure, hygiene care and skin care behavior.

Keywords: aging, hygiene care, pruritus, skin care, sun exposure

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6808 Analysis of Delays during Initial Phase of Construction Projects and Mitigation Measures

Authors: Sunaitan Al Mutairi

Abstract:

A perfect start is a key factor for project completion on time. The study examined the effects of delayed mobilization of resources during the initial phases of the project. This paper mainly highlights the identification and categorization of all delays during the initial construction phase and their root cause analysis with corrective/control measures for the Kuwait Oil Company oil and gas projects. A relatively good percentage of the delays identified during the project execution (Contract award to end of defects liability period) attributed to mobilization/preliminary activity delays. Data analysis demonstrated significant increase in average project delay during the last five years compared to the previous period. Contractors had delays/issues during the initial phase, which resulted in slippages and progressively increased, resulting in time and cost overrun. Delays/issues not mitigated on time during the initial phase had very high impact on project completion. Data analysis of the delays for the past five years was carried out using trend chart, scatter plot, process map, box plot, relative importance index and Pareto chart. Construction of any project inside the Gathering Centers involves complex management skills related to work force, materials, plant, machineries, new technologies etc. Delay affects completion of projects and compromises quality, schedule and budget of project deliverables. Works executed as per plan during the initial phase and start-up duration of the project construction activities resulted in minor slippages/delays in project completion. In addition, there was a good working environment between client and contractor resulting in better project execution and management. Mainly, the contractor was on the front foot in the execution of projects, which had minimum/no delays during the initial and construction period. Hence, having a perfect start during the initial construction phase shall have a positive influence on the project success. Our research paper studies each type of delay with some real example supported by statistic results and suggests mitigation measures. Detailed analysis carried out with all stakeholders based on impact and occurrence of delays to have a practical and effective outcome to mitigate the delays. The key to improvement is to have proper control measures and periodic evaluation/audit to ensure implementation of the mitigation measures. The focus of this research is to reduce the delays encountered during the initial construction phase of the project life cycle.

Keywords: construction activities delays, delay analysis for construction projects, mobilization delays, oil & gas projects delays

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6807 Influence of Well-Being and Quality of Work-Life on Quality of Care among Health Professionals in Southwest Nigeria

Authors: Adesola C. Odole, Michael O. Ogunlana, Nse A. Odunaiya, Olufemi O. Oyewole, Chidozie E. Mbada, Ogochukwu K. Onyeso, Ayomikun F. Ayodeji, Opeyemi M. Adegoke, Iyanuoluwa Odole, Comfort T. Sanuade, Moyosooreoluwa E. Odole, Oluwagbohunmi A. Awosoga

Abstract:

Purpose: The Nigerian healthcare industry is bedeviled with infrastructural decay, inadequate funding and staffing, and a dysfunctional healthcare system. This study investigated the influence of health professionals’ well-being and quality of work-life (QoWL) on the quality of care (QoC) of patients in Nigeria. Methods: The study was a multicentre cross-sectional survey conducted at four tertiary health institutions in southwest Nigeria. Participants’ demographic information, well-being, quality of work-life, and quality of care were obtained using four standardized questionnaires. Data were summarized using descriptive statistics of frequency (percentage) and mean (standard deviation). Inferential statistics included Chi-square, Pearson’s correlation, and independent samples t-test analyses. Results: Medical practitioners (n=609) and nurses (n=570) constituted 74.6% of all the health professionals, with physiotherapists, pharmacists, and medical laboratory scientists constituting 25.4%. The mean (SD) participants’ well-being = 71.65% (14.65), quality of life = 61.8% (21.31), quality of work-life = 65.73% (10.52) and quality of care = 70.14% (12.77). Participants’ quality of life had a significant negative correlation with the quality of care, while well-being and quality of work-life had a significant positive correlation with the quality of care. Conclusion: We concluded that health professionals’ well-being and quality of work-life are important factors that influence their productivity and, ultimately, the quality of care rendered to patients. The hospital management and policymakers should ensure improved work-related factors to improve the well-being of health professionals. This will enhance the quality of care given to patients and ultimately reduce brain drain and medical tourism.

Keywords: health professionals, quality of care, quality of life, quality of work-life, well-being

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6806 A Study of the Relationship between Time Management Behaviour and Job Satisfaction of Higher Education Institutes in India

Authors: Sania K. Rao, Feza T. Azmi

Abstract:

The purpose of the present study is to explore the relationship between time management behaviour and job satisfaction of academicians of higher education institutes in India. The analyses of this study were carried out with AMOS (version 20.0); and Confirmatory Factor Analysis (CFA) and Structural Equation Modelling (SEM) were conducted. The factor analysis and findings show that perceived control of time serves as the partial mediating factor to have a significant and positive influence on job satisfaction. Further, at the end, a number of suggestions to improve one’s time management behaviour were provided.

Keywords: time management behaviour, job satisfaction, higher education, India, mediation analysis

Procedia PDF Downloads 395
6805 Radical Scavenging Activity of Protein Extracts from Pulse and Oleaginous Seeds

Authors: Silvia Gastaldello, Maria Grillo, Luca Tassoni, Claudio Maran, Stefano Balbo

Abstract:

Antioxidants are nowadays attractive not only for the countless benefits to the human and animal health, but also for the perspective of use as food preservative instead of synthetic chemical molecules. In this study, the radical scavenging activity of six protein extracts from pulse and oleaginous seeds was evaluated. The selected matrices are Pisum sativum (yellow pea from two different origins), Carthamus tinctorius (safflower), Helianthus annuus (sunflower), Lupinus luteus cv Mister (lupin) and Glycine max (soybean), since they are economically interesting for both human and animal nutrition. The seeds were grinded and proteins extracted from 20mg powder with a specific vegetal-extraction kit. Proteins have been quantified through Bradford protocol and scavenging activity was revealed using DPPH assay, based on radical DPPH (2,2-diphenyl-1-picrylhydrazyl) absorbance decrease in the presence of antioxidants molecules. Different concentrations of the protein extract (1, 5, 10, 50, 100, 500 µg/ml) were mixed with DPPH solution (DPPH 0,004% in ethanol 70% v/v). Ascorbic acid was used as a scavenging activity standard reference, at the same six concentrations of protein extracts, while DPPH solution was used as control. Samples and standard were prepared in triplicate and incubated for 30 minutes in dark at room temperature, the absorbance was read at 517nm (ABS30). Average and standard deviation of absorbance values were calculated for each concentration of samples and standard. Statistical analysis using t-students and p-value were performed to assess the statistical significance of the scavenging activity difference between the samples (or standard) and control (ABSctrl). The percentage of antioxidant activity has been calculated using the formula [(ABSctrl-ABS30)/ABSctrl]*100. The obtained results demonstrate that all matrices showed antioxidant activity. Ascorbic acid, used as standard, exhibits a 96% scavenging activity at the concentration of 500 µg/ml. At the same conditions, sunflower, safflower and yellow peas revealed the highest antioxidant performance among the matrices analyzed, with an activity of 74%, 68% and 70% respectively (p < 0.005). Although lupin and soybean exhibit a lower antioxidant activity compared to the other matrices, they showed a percentage of 46 and 36 respectively. All these data suggest the possibility to use undervalued edible matrices as antioxidants source. However, further studies are necessary to investigate a possible synergic effect of several matrices as well as the impact of industrial processes for a large-scale approach.

Keywords: antioxidants, DPPH assay, natural matrices, vegetal proteins

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6804 Electrochemical Layer by Layer Assembly

Authors: Mao Li, Yuguang Ma, Katsuhiko Ariga

Abstract:

The performance of functional materials is governed by their ability to interact with surrounding environments in a well-defined and controlled manner. Layer-by-Layer (LbL) assembly is one of the most widely used technologies for coating both planar and particulate substrates in a diverse range of fields, including optics, energy, catalysis, separations, and biomedicine. Herein, we introduce electrochemical-coupling layer-by-layer assembly as a novel fabrication methodology for preparing layered thin films. This assembly method not only determines the process properties (such as the time, scalability, and manual intervention) but also directly control the physicochemical properties of the films (such as the thickness, homogeneity, and inter- and intra-layer film organization), with both sets of properties linked to application-specific performance.

Keywords: layer by layer assembly, electropolymerization, carbazole, optical thin film, electronics

Procedia PDF Downloads 389