Search results for: efficiency coefficient
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8572

Search results for: efficiency coefficient

7732 Simulation of Government Management Model to Increase Financial Productivity System Using Govpilot

Authors: Arezou Javadi

Abstract:

The use of algorithmic models dependent on software calculations and simulation of new government management assays with the help of specialized software had increased the productivity and efficiency of the government management system recently. This has caused the management approach to change from the old bitch & fix model, which has low efficiency and less usefulness, to the capable management model with higher efficiency called the partnership with resident model. By using Govpilot TM software, the relationship between people in a system and the government was examined. The method of two tailed interaction was the outsourcing of a goal in a system, which is formed in the order of goals, qualified executive people, optimal executive model, and finally, summarizing additional activities at the different statistical levels. The results showed that the participation of people in a financial implementation system with a statistical potential of P≥5% caused a significant increase in investment and initial capital in the government system with maximum implement project in a smart government.

Keywords: machine learning, financial income, statistical potential, govpilot

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7731 Enhancing the Efficiency of Organic Solar Cells Using Metallic Nanoparticles

Authors: Sankara Rao Gollu, Ramakant Sharma, G. Srinivas, Souvik Kundu, Dipti Gupta

Abstract:

In recent years, bulk heterojunction organic solar cells (BHJ OSCs) based on polymer–fullerene attracted a large research attention due to their numerous advantages such as light weight, easy processability, eco-friendly, low-cost, and capability for large area roll-to-roll manufacturing. BHJ OSCs usually suffer from insufficient light absorption due to restriction on keeping thin ( < 150 nm) photoactive layer because of small exciton diffusion length ( ~ 10 nm) and low charge carrier mobilities. It is thus highly desirable that light absorption as well as charge transport properties are enhanced by alternative methods so as to improve the device efficiency. In this work, therefore, we have focused on the strategy of incorporating metallic nanostructures in the active layer or charge transport layer to enhance the absorption and improve the charge transport.

Keywords: organic solar cell, efficiency, bulk heterojunction, polymer-fullerene

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7730 Assessment of Metal and Nano-Metal Doped TiO₂ Nanoparticles for Photocatalytic Degradation of Methylene Blue in Almeda Textile Industry, Tigray, Ethiopia

Authors: Mulugeta Gurum Gerechal

Abstract:

Nowadays, the photocatalytic mechanism of water purification using nanoparticles has gained wider acceptance. For this purpose, the Crystal form of N- TiO₂ and Ag-TiO₂ was prepared from TiCl₄, Urea, NH₄OH and AgNO₃ by sol-gel method and simple solid phase reaction followed by calcination at a temperature of 400 °C for 4h at each. The synthesized photocatalysts were characterized using XRD, SEM and UV-visible diffuse reflectance spectra. In the experiment, it was found that the absorption edge of N-TiO₂ was a well efficient shift to visible light as compared to Ag-TiO₂. The XRD diffraction makes the particle size of N-TiO₂ smaller than Ag-TiO₂. The effect of catalyst loading and the effect of temperature on the photocatalytic efficiency of the prepared samples was tested using methylene blue as a target pollutant. The photocatalytic degradation efficiency of the catalysts for methylene blue was increased from 57.05 to 96.02% under solar radiation as the amount of the catalyst increased from 0.15 to 0.45 gram for N-TiO₂. Similarly, photocatalytic degradation of methylene blue was increased from 40.32 to 81.21% as the amount of Ag-TiO₂ increased from 0.05g to 0.1g. In addition, the photocatalytic degradation efficiency of the catalysts for the removal of methylene blue was increased from 58.00 to 98.00 and 47.00 to 81.21 % under solar radiation as the calcination temperature of the catalyst increased from 300 to 500 for N-TiO₂ for Ag-TiO₂ 300 to 4000C. However, a further increase in catalyst loading and calcination temperature was found to decrease the degradation efficiency.

Keywords: photocatalysis, degradation, nanoparticles, catalyst loading, calcination and methylene blue

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7729 Numerical Modeling of hybrid Photovoltaic-Thermoelectric Solar Unit by Applying Various Cross-Sections of Cooling Ducts

Authors: Ziba Khalili, Mohsen Sheikholeslami, Ladan Momayez

Abstract:

Combining the photovoltaic/thermal (PVT) systems with a thermoelectric (TE) module can raise energy yields since the TE module boosts the system's energy conversion efficiency. In the current study, a PVT system integrated with a TE module was designed and simulated in ANSYS Fluent 19.2. A copper heat transfer tube (HTT) was employed for cooling the photovoltaic (PV) cells. Four different shapes of HTT cross-section, i.e., circular, square, elliptical, and triangular, with equal cross-section areas were investigated. Also, the influence of Cu-Al2O3/water hybrid nanofluid (0.024% volume concentration), fluid inlet velocity (uᵢ ), and amount of solar radiation (G), on the PV temperature (Tₚᵥ) and system performance were investigated. The ambient temperature (Tₐ), wind speed (u𝓌), and fluid inlet temperature (Tᵢ), were considered to be 25°C, 1 m/s, and 27°C, respectively. According to the obtained data, the triangular case had the greatest impact on reducing the compared to other cases. In the triangular case, examination of the effect of hybrid nanofluid showed that the use of hybrid nanofluid at 800 W/m2 led to a reduction of the TPV by 0.6% compared to water, at 0.19 m/s. Moreover, the thermal efficiency ( ) and the overall electrical efficiency (nₜ) of the system improved by 0.93% and 0.22%, respectively, at 0.19 m/s. In a triangular case where G and were 800 W/m2 and 19 m/s, respectively, the highest amount of, thermal power (Eₜ), and, were obtained as 72.76%, 130.84 W and 12.03%, respectively.

Keywords: electrical performance, photovoltaic/thermal, thermoelectric, hybrid nanofluid, thermal efficiency

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7728 Regionalization of IDF Curves with L-Moments for Storm Events

Authors: Noratiqah Mohd Ariff, Abdul Aziz Jemain, Mohd Aftar Abu Bakar

Abstract:

The construction of Intensity-Duration-Frequency (IDF) curves is one of the most common and useful tools in order to design hydraulic structures and to provide a mathematical relationship between rainfall characteristics. IDF curves, especially those in Peninsular Malaysia, are often built using moving windows of rainfalls. However, these windows do not represent the actual rainfall events since the duration of rainfalls is usually prefixed. Hence, instead of using moving windows, this study aims to find regionalized distributions for IDF curves of extreme rainfalls based on storm events. Homogeneity test is performed on annual maximum of storm intensities to identify homogeneous regions of storms in Peninsular Malaysia. The L-moment method is then used to regionalized Generalized Extreme Value (GEV) distribution of these annual maximums and subsequently. IDF curves are constructed using the regional distributions. The differences between the IDF curves obtained and IDF curves found using at-site GEV distributions are observed through the computation of the coefficient of variation of root mean square error, mean percentage difference and the coefficient of determination. The small differences implied that the construction of IDF curves could be simplified by finding a general probability distribution of each region. This will also help in constructing IDF curves for sites with no rainfall station.

Keywords: IDF curves, L-moments, regionalization, storm events

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7727 Budget and the Performance of Public Enterprises: A Study of Selected Public Enterprises in Nasarawa State Nigeria (2009-2013)

Authors: Dalhatu, Musa Yusha’u, Shuaibu Sidi Safiyanu, Haliru Musa Hussaini

Abstract:

This study examined budget and performance of public enterprises in Nasarawa State, Nigeria in a period of 2009-2013. The study utilized secondary sources of data obtained from four selected parastatals’ budget allocation and revenue generation for the period under review. The simple correlation coefficient was used to analyze the extent of the relationship between budget allocation and revenue generation of the parastatals. Findings revealed varying results. There was positive (0.21) and weak correlation between expenditure and revenue of Nasarawa Investment and Property Development Company (NIPDC). However, the study further revealed that there was strong and weak negative relationship in the revenue and expenditure of the following parastatals over the period under review. Viz: Nasarawa State Water Board, -0.27 (weak), Nasarawa State Broadcasting Service, -0.52 (Strong) and Nasarawa State College of Agriculture, -0.36 (weak). The study therefore, recommends that government should increase its investments in NIPDC to enhance efficiency and profitability. It also recommends that government should strengthen its fiscal responsibility, accountability and transparency in public parastatals.

Keywords: budget, public enterprises, revenue, enterprise

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7726 On the Fourth-Order Hybrid Beta Polynomial Kernels in Kernel Density Estimation

Authors: Benson Ade Eniola Afere

Abstract:

This paper introduces a family of fourth-order hybrid beta polynomial kernels developed for statistical analysis. The assessment of these kernels' performance centers on two critical metrics: asymptotic mean integrated squared error (AMISE) and kernel efficiency. Through the utilization of both simulated and real-world datasets, a comprehensive evaluation was conducted, facilitating a thorough comparison with conventional fourth-order polynomial kernels. The evaluation procedure encompassed the computation of AMISE and efficiency values for both the proposed hybrid kernels and the established classical kernels. The consistently observed trend was the superior performance of the hybrid kernels when compared to their classical counterparts. This trend persisted across diverse datasets, underscoring the resilience and efficacy of the hybrid approach. By leveraging these performance metrics and conducting evaluations on both simulated and real-world data, this study furnishes compelling evidence in favour of the superiority of the proposed hybrid beta polynomial kernels. The discernible enhancement in performance, as indicated by lower AMISE values and higher efficiency scores, strongly suggests that the proposed kernels offer heightened suitability for statistical analysis tasks when compared to traditional kernels.

Keywords: AMISE, efficiency, fourth-order Kernels, hybrid Kernels, Kernel density estimation

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7725 Time Driven Activity Based Costing Capability to Improve Logistics Performance: Application in Manufacturing Context

Authors: Siham Rahoui, Amr Mahfouz, Amr Arisha

Abstract:

In a highly competitive environment characterised by uncertainty and disruptions, such as the recent COVID-19 outbreak, supply chains (SC) face the challenge of maintaining their cost at minimum levels while continuing to provide customers with high-quality products and services. More importantly, businesses in such an economic context strive to maintain survival by keeping the cost of undertaken activities (such as logistics) low and in-house. To do so, managers need to understand the costs associated with different products and services in order to have a clear vision of the SC performance, maintain profitability levels, and make strategic decisions. In this context, SC literature explored different costing models that sought to determine the costs of undertaking supply chain-related activities. While some cost accounting techniques have been extensively explored in the SC context, more contributions are needed to explore the potential of time driven activity-based costing (TDABC). More specifically, more applications are needed in the manufacturing context of the SC, where the debate is ongoing. The aim of the study is to assess the capability of the technique to assess the operational performance of the logistics function. Through a case study methodology applied to a manufacturing company operating in the automotive industry, TDABC evaluates the efficiency of the current configuration and its logistics processes. The study shows that monitoring the process efficiency and cost efficiency leads to strategic decisions that contributed to improve the overall efficiency of the logistics processes.

Keywords: efficiency, operational performance, supply chain costing, time driven activity based costing

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7724 Enhancement of Light Out Efficiency of PLED Device Employing Designed Substrate Combined with Nano-Line Patterns

Authors: Ting-Ting Wen, H. C. Lin

Abstract:

This paper reports a study for the light outcoupling efficiency of the PLED device. In use of a designed substrate combined with nano-line patterns in PLED device, the light outcoupling efficiency can be significantly enhanced. The designed substrate was made by UV imprinting technology, such as triangular microlens arrays on the front and periodic corrugated patterns on the back surface. The nano-line patterns in PLED device was fabricated by advanced microstamping and ink-jet printing techniques. For high angles of observation with respect to the substrate surface normal, the light out intensity of the developed PLED device is increased from 0.05 (a.u.) up to 0.69 (a.u.) at the view angle 85 degree. The designed integration leads to 64% increase of the light out intensity compared with the conventional PLED device.

Keywords: triangular microlens, corrugation patterns, nano-line patterns, PLED device, UV imprinting technology, microstamping

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7723 Efficiency of Using E-Wallets as Payment Method in Marikina City During COVID-19 Pandemic

Authors: Noel Paolo Domingo, James Paul Menina, Laurente Ferrer

Abstract:

Most people were forced to stay at home and limit their physical contact during the COVID-19 pandemic. Due to the situation, strict implementation of government policies and safety protocols encouraged consumers to utilize cashless or digital transactions through e-wallets. In this study, the researchers aim to investigate the efficiency of using e-wallets as a payment method during the COVID-19 pandemic in Marikina City. The study examined the efficiency of e-wallets in terms of Usefulness, Convenience, and Safety and Security based on respondents’ assessment. Questionnaires developed by the researchers were distributed to a total of 400 e-wallet users in Marikina City aged 15 years old and above to gather data by using a purposive sampling technique. The data collected was processed using SPSS version 26. Frequency, percentage, and mean were utilized to describe the profile of respondents and their assessment of e-wallets in terms of the three constructs. ANOVA and t-tests were also employed to test the significant differences in the respondent’s assessment when the demographic profile was considered. The study revealed that when it comes to usefulness, e-wallet is efficient while in terms of convenience, and safety and security, e-wallet has been proven to be very efficient. During the COVID-19 pandemic, utilizing e-wallets has been embraced by most consumers. By enhancing its features, more people will be satisfied with using e-wallets.

Keywords: efficiency of e-wallets, usefulness, convenience, safety and security

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7722 Mixed Alumina-Silicate Materials for Groundwater Remediation

Authors: Ziyad Abunada, Abir Al-tabbaa

Abstract:

The current work is investigating the effectiveness of combined mixed materials mainly modified bentonites and organoclay in treating contaminated groundwater. Sodium bentonite was manufactured with a quaternary amine surfactant, dimethyl ammonium chloride to produce organoclay (OC). Inorgano-organo bentonite (IOB) was produced by intercalating alkylbenzyd-methyl-ammonium chloride surfactant into sodium bentonite and pillared with chlorohydrol pillaring agent. The materials efficiency was tested for both TEX compounds from model-contaminated water and a mixture of organic contaminants found in groundwater samples collected from a contaminated site in the United Kingdom. The sorption data was fitted well to both Langmuir and Freundlich adsorption models reflecting the double sorption model where the correlation coefficient was greater than 0.89 for all materials. The mixed materials showed higher sorptive capacity than individual material with a preference order of X> E> T and a maximum sorptive capacity of 21.8 mg/g was reported for IOB-OC materials for o-xylene. The mixed materials showed at least two times higher affinity towards a mixture of organic contaminants in groundwater samples. Other experimental parameters such as pH and contact time were also investigated. The pseudo-second-order rate equation was able to provide the best description of adsorption kinetics.

Keywords: modified bentobite, groundwater, adsorption, contaminats

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7721 Understanding the Performance and Loss Mechanisms in Ag Alloy CZTS Solar Cells: Photocurrent Generation, Charge Separation, and Carrier Transport

Authors: Kang Jian Xian, Huda Abdullah, Md. Akhtaruzzaman, Iskandar Yahya, Mohd Hafiz Dzarfan Othman, Brian Yulianto

Abstract:

The CZTS absorber layer doped with a silver (Ag) is one of the candidates that suggest improving the efficiency of thin films. Silver element functions to reduce antisite defects, increase grain size and create the plasmonic effect. In this work, an experimental study has been done to investigate the electrical and physical properties of CZTS, ACZTS, and AZTS. Ag replaces the Cu in (Cu1-xAgx)2ZnSnS4 (ACZTS) is up to x ≤1. ACZTS thin-films solar cells have been deposited by sol–the gel spin coating method. There are a total of 19 samples done with 11 significant percentages (0%, 10%, 20%… 100%) to show the whole phenomena of efficiency rate and nine specific percentages to find out the best concentration rate for Ag-doped. The obtained results can be helpful for better understanding ACZTS layers.

Keywords: CZTS, ACZTS, AZTS, silver, antisite, efficiency, thin-film solar cell

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7720 Porous Bluff-Body Disc on Improving the Gas-Mixing Efficiency

Authors: Shun-Chang Yen, You-Lun Peng, Kuo-Ching San

Abstract:

A numerical study on a bluff-body structure with multiple holes was conducted using ANSYS Fluent computational fluid dynamics analysis. The effects of the hole number and jet inclination angles were considered under a fixed gas flow rate and nonreactive gas. The bluff body with multiple holes can transform the axial momentum into a radial and tangential momentum as well as increase the swirl number (S). The concentration distribution in the mixing of a central carbon dioxide (CO2) jet and an annular air jet was utilized to analyze the mixing efficiency. Three bluff bodies with differing hole numbers (H = 3, 6, and 12) and three jet inclination angles (θ = 45°, 60°, and 90°) were designed for analysis. The Reynolds normal stress increases with the inclination angle. The Reynolds shear stress, average turbulence intensity, and average swirl number decrease with the inclination angle. For an unsymmetrical hole configuration (i.e., H = 3), the streamline patterns exhibited an unsymmetrical flow field. The highest mixing efficiency (i.e., the lowest integral gas fraction of CO2) occurred at H = 3. Furthermore, the highest swirl number coincided with the strongest effect on the mass fraction of CO2. Therefore, an unsymmetrical hole arrangement induced a high swirl flow behind the porous disc.

Keywords: bluff body with multiple holes, computational fluid dynamics, swirl-jet flow, mixing efficiency

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7719 Preparation and Characterization of Chitosan Nanoparticles for Delivery of Oligonucleotides

Authors: Gyati Shilakari Asthana, Abhay Asthana, Dharm Veer Kohli, Suresh Prasad Vyas

Abstract:

Purpose: The therapeutic potential of oligonucleotide (ODN) is primarily dependent upon its safe and efficient delivery to specific cells overcoming degradation and maximizing cellular uptake in vivo. The present study is focused to design low molecular weight chitosan nanoconstructs to meet the requirements of safe and effectual delivery of ODNs. LMW-chitosan is a biodegradable, water soluble, biocompatible polymer and is useful as a non-viral vector for gene delivery due to its better stability in water. Methods: LMW chitosan ODN nanoparticles (CHODN NPs) were formulated by self-assembled method using various N/P ratios (moles ratio of amine groups of CH to phosphate moieties of ODNs; 0.5:1, 1:1, 3:1, 5:1, and 7:1) of CH to ODN. The developed CHODN NPs were evaluated with respect to gel retardation assay, particle size, zeta potential and cytotoxicity and transfection efficiency. Results: Complete complexation of CH/ODN was achieved at the charge ratio of 0.5:1 or above and CHODN NPs displayed resistance against DNase I. On increasing the N/P ratio of CH/ODN, the particle size of the NPs decreased whereas zeta potential (ZV) value increased. No significant toxicity was observed at all CH concentrations. The transfection efficiency was increased on increasing N/P ratio from 1:1 to 3:1, whereas it was decreased with further increment in N/P ratio upto 7:1. Maximum transfection of CHODN NPs with both the cell lines (Raw 267.4 cells and Hela cells) was achieved at N/P ratio of 3:1. The results suggest that transfection efficiency of CHODN NPs is dependent on N/P ratio. Conclusion: Thus the present study states that LMW chitosan nanoparticulate carriers would be acceptable choice to improve transfection efficiency in vitro as well as in vivo delivery of oligonucleotide.

Keywords: LMW-chitosan, chitosan nanoparticles, biocompatibility, cytotoxicity study, transfection efficiency, oligonucleotide

Procedia PDF Downloads 849
7718 Governance and Public Policy: The Perception of Efficiency and Equility in Brazil and South Africa

Authors: Paulino V. Tavares, Ana L. Romao

Abstract:

Public governance represents an articulated arrangement, dynamic and interactive, present in the exercise of authority aimed at strengthening the decision-making procedure in public administration with transparency, accountability, responsiveness and capable of to emerge control and social empowerment, to pursue and achieve the objectives efficiently and with the effectiveness desired by the collective, respecting laws and providing social, institutional and economic equility in society. With this, using a multidimensional approach with the application of three questionnaires to a universe of twenty Counselors of the Courts of Auditors (Brazil), twenty professionals of public administration (Brazil), twenty Government/Provincial Counselors (South Africa), and twenty South African professionals of public administration, the present work aims to capture what is the perception about the efficiency and equility of public policies in Brazil and South Africa. With this, up until now, 30 responses have been obtained, and the results indicate that, in Brazil, 65% affirm due to the inefficiency of public policies, 70% point out that they do not believe in the equility of these same policies. In South Africa, the results indicate that 45% believe in government efficiency, and, with regard to the equility of public policies, 65% do not believe. In Brazil, the research reveals at least three reasons for this result, that is, lack of planning, lack of clear objectives of public policies, and lack of information on the part of society, while in South Africa, so far, research has not identified a specific reason for this result.

Keywords: efficiency, equility, governance, public policy

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7717 Investigating the Efficiency of Granular Sludge for Recovery of Phosphate from Wastewater

Authors: Sara Salehi, Ka Yu Cheng, Anna Heitz, Maneesha Ginige

Abstract:

This study investigated the efficiency of granular sludge for phosphorous (P) recovery from wastewater. A laboratory scale sequencing batch reactor (SBR) was operated under alternating aerobic/anaerobic conditions to enrich a P accumulating granular biomass. This study showed that an overall 45-fold increase in P concentration could be achieved by reducing the volume of the P capturing liquor by 5-fold in the anaerobic P release phase. Moreover, different fractions of the granular biomass have different individual contributions towards generating a concentrated stream of P.

Keywords: granular sludge, PAOs, P recovery, SBR

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7716 Generalized Correlation Coefficient in Genome-Wide Association Analysis of Cognitive Ability in Twins

Authors: Afsaneh Mohammadnejad, Marianne Nygaard, Jan Baumbach, Shuxia Li, Weilong Li, Jesper Lund, Jacob v. B. Hjelmborg, Lene Christensen, Qihua Tan

Abstract:

Cognitive impairment in the elderly is a key issue affecting the quality of life. Despite a strong genetic background in cognition, only a limited number of single nucleotide polymorphisms (SNPs) have been found. These explain a small proportion of the genetic component of cognitive function, thus leaving a large proportion unaccounted for. We hypothesize that one reason for this missing heritability is the misspecified modeling in data analysis concerning phenotype distribution as well as the relationship between SNP dosage and the phenotype of interest. In an attempt to overcome these issues, we introduced a model-free method based on the generalized correlation coefficient (GCC) in a genome-wide association study (GWAS) of cognitive function in twin samples and compared its performance with two popular linear regression models. The GCC-based GWAS identified two genome-wide significant (P-value < 5e-8) SNPs; rs2904650 near ZDHHC2 on chromosome 8 and rs111256489 near CD6 on chromosome 11. The kinship model also detected two genome-wide significant SNPs, rs112169253 on chromosome 4 and rs17417920 on chromosome 7, whereas no genome-wide significant SNPs were found by the linear mixed model (LME). Compared to the linear models, more meaningful biological pathways like GABA receptor activation, ion channel transport, neuroactive ligand-receptor interaction, and the renin-angiotensin system were found to be enriched by SNPs from GCC. The GCC model outperformed the linear regression models by identifying more genome-wide significant genetic variants and more meaningful biological pathways related to cognitive function. Moreover, GCC-based GWAS was robust in handling genetically related twin samples, which is an important feature in handling genetic confounding in association studies.

Keywords: cognition, generalized correlation coefficient, GWAS, twins

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7715 Smart Surveillance with 5G: A Performance Study in Adama City

Authors: Shenko Chura Aredo, Hailu Belay, Kevin T. Kornegay

Abstract:

In light of Adama City’s smart city development vision, this study thoroughly investigates the performance of smart security systems with Fifth Generation (5G) network capabilities. It can be logistically difficult to install a lot of cabling, particularly in big or dynamic settings. Moreover, latency issues might affect linked systems, making it difficult for them to monitor in real time. Through a focused analysis that employs Adama City as a case study, the performance has been evaluated in terms of spectrum and energy efficiency using empirical data and basic signal processing formulations at different frequency resources. The findings also demonstrate that cameras working at higher 5G frequencies have more capacity than those operating at sub-6 GHz, notwithstanding frequency-related issues. It has also been noted that when the beams of such cameras are adaptively focussed based on the distance of the last cell edge user rather than the maximum cell radius, less energy is required than with conventional fixed power ramping.

Keywords: 5G, energy efficiency, safety, smart security, spectral efficiency

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7714 The Volume–Volatility Relationship Conditional to Market Efficiency

Authors: Massimiliano Frezza, Sergio Bianchi, Augusto Pianese

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The relation between stock price volatility and trading volume represents a controversial issue which has received a remarkable attention over the past decades. In fact, an extensive literature shows a positive relation between price volatility and trading volume in the financial markets, but the causal relationship which originates such association is an open question, from both a theoretical and empirical point of view. In this regard, various models, which can be considered as complementary rather than competitive, have been introduced to explain this relationship. They include the long debated Mixture of Distributions Hypothesis (MDH); the Sequential Arrival of Information Hypothesis (SAIH); the Dispersion of Beliefs Hypothesis (DBH); the Noise Trader Hypothesis (NTH). In this work, we analyze whether stock market efficiency can explain the diversity of results achieved during the years. For this purpose, we propose an alternative measure of market efficiency, based on the pointwise regularity of a stochastic process, which is the Hurst–H¨older dynamic exponent. In particular, we model the stock market by means of the multifractional Brownian motion (mBm) that displays the property of a time-changing regularity. Mostly, such models have in common the fact that they locally behave as a fractional Brownian motion, in the sense that their local regularity at time t0 (measured by the local Hurst–H¨older exponent in a neighborhood of t0 equals the exponent of a fractional Brownian motion of parameter H(t0)). Assuming that the stock price follows an mBm, we introduce and theoretically justify the Hurst–H¨older dynamical exponent as a measure of market efficiency. This allows to measure, at any time t, markets’ departures from the martingale property, i.e. from efficiency as stated by the Efficient Market Hypothesis. This approach is applied to financial markets; using data for the SP500 index from 1978 to 2017, on the one hand we find that when efficiency is not accounted for, a positive contemporaneous relationship emerges and is stable over time. Conversely, it disappears as soon as efficiency is taken into account. In particular, this association is more pronounced during time frames of high volatility and tends to disappear when market becomes fully efficient.

Keywords: volume–volatility relationship, efficient market hypothesis, martingale model, Hurst–Hölder exponent

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7713 Efficiency Analysis of Trader in Thailand and Laos Border Trade: Case Study of Textile and Garment Products

Authors: Varutorn Tulnawat, Padcharee Phasuk

Abstract:

This paper investigates the issue of China’s dumping on border trade between Thailand and Laos. From the pass mostly, the border trade goods are traditional textile and garment mainly served locals and tourists which majority of traders is of small and medium size. In the present day the competition is fierce, the volume of trade has expanded far beyond its original intent. The major competitors in Thai-Laos border trade are China, Vietnam and also South Korea. This research measures and compares the efficiency and ability to survive the onslaught of Thai and Laos firm along Thailand (Nong Kai province) and Laos (Vientiane) border. Two attack strategies are observed, price cutting and incense such as full facilitation for big volume order. Data Envelopment Analysis (DEA) is applied to data surveyed from 90 Thai and Laos entrepreneurs. The expected results are the proportion of efficiency and inefficiency firms. Points of inefficiency and suggested improvement are also discussed.

Keywords: border trade, dea, textile, garment

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7712 Payment Subsidies for Environmentally-Friendly Agriculture on Rice Production in Japan

Authors: Danielle Katrina Santos, Koji Shimada

Abstract:

Environmentally-friendly agriculture has been promoted for over two decades as a response to the environmental challenges brought by climate change and biological loss. Located above the equator, it is possible that Japan may benefit from future climate change, yet Japan is also a rarely developed country located in the Asian Monsoon climate region, making it vulnerable to the impacts of climate change. In this regard, the Japanese government has initiated policies to adapt to the adverse effects of climate change through the promotion and popularization of environmentally-friendly farming practices. This study aims to determine profit efficiency among environmentally-friendly rice farmers in Shiga Prefecture using the Stochastic Frontier Approach. A cross-sectional survey was conducted among 66 farmers from top rice-producing cities through a structured questionnaire. Results showed that the gross farm income of environmentally-friendly rice farmers was higher by JPY 316,223.00/ha. Production costs were also found to be higher among environmentally-friendly rice farmers, especially on labor costs, which accounted for 32% of the total rice production cost. The resulting net farm income of environmentally-friendly rice farmers was only higher by JPY 18,044/ha. Results from the stochastic frontier analysis further showed that the profit efficiency of conventional farmers was only 69% as compared to environmentally-friendly rice farmers who had a profit efficiency of 76%. Furthermore, environmentally-friendly agriculture participation, other types of subsidy, educational level, and farm size were significant factors positively influencing profit efficiency. The study concluded that substitution of environmentally-friendly agriculture for conventional rice farming would result in an increased profit efficiency due to the direct payment subsidy and price premium received. The direct government policies that would strengthen the popularization of environmentally-friendly agriculture to increase the production of environmentally-friendly products and reduce pollution load to the Lake Biwa ecosystem.

Keywords: profit efficiency, environmentally-friendly agriculture, rice farmers, direct payment subsidies

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7711 Correlation Mapping for Measuring Platelet Adhesion

Authors: Eunseop Yeom

Abstract:

Platelets can be activated by the surrounding blood flows where a blood vessel is narrowed as a result of atherosclerosis. Numerous studies have been conducted to identify the relation between platelets activation and thrombus formation. To measure platelet adhesion, this study proposes an image analysis technique. Blood samples are delivered in the microfluidic channel, and then platelets are activated by a stenotic micro-channel with 90% severity. By applying proposed correlation mapping, which visualizes decorrelation of the streaming blood flow, the area of adhered platelets (APlatelet) was estimated without labeling platelets. In order to evaluate the performance of correlation mapping on the detection of platelet adhesion, the effect of tile size was investigated by calculating 2D correlation coefficients with binary images obtained by manual labeling and the correlation mapping method with different sizes of the square tile ranging from 3 to 50 pixels. The maximum 2D correlation coefficient is observed with the optimum tile size of 5×5 pixels. As the area of the platelet adhesion increases, the platelets plug the channel and there is only a small amount of blood flows. This image analysis could provide new insights for better understanding of the interactions between platelet aggregation and blood flows in various physiological conditions.

Keywords: platelet activation, correlation coefficient, image analysis, shear rate

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7710 Significance of Bike-Frame Geometric Factors for Cycling Efficiency and Muscle Activation

Authors: Luen Chow Chan

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With the advocacy of green transportation and green traveling, cycling has become increasingly popular nowadays. Physiology and bike design are key factors for the influence of cycling efficiency. Therefore, this study aimed to investigate the significance of bike-frame geometric factors on cycling efficiency and muscle activation for different body sizes of non-professional Asian male cyclists. Participants who represented various body sizes, as measured by leg and back lengths, carried out cycling tests using a tailor-assembled road bike with different ergonomic design configurations including seat-height adjustments (i.e., 96%, 100%, and 104% of trochanteric height) and bike frame sizes (i.e., small and medium frames) for an assessable distance of 1 km. A specific power meter and self-developed adaptable surface electromyography (sEMG) were used to measure average pedaling power and cadence generated and muscle activation, respectively. The results showed that changing the seat height was far more significant than the body and bike frame sizes. The sEMG data evidently provided a better understanding of muscle activation as a function of different seat heights. Therefore, the interpretation of this study is that the major bike ergonomic design factor dominating the cycling efficiency of Asian participants with different body sizes was the seat height.

Keywords: bike frame sizes, cadence rate, pedaling power, seat height

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7709 A Computational Fluid Dynamics Study of Turbulence Flow and Parameterization of an Aerofoil

Authors: Mohamed Z. M. Duwahir, Shian Gao

Abstract:

The main objective of this project was to introduce and test a new scheme for parameterization of subsonic aerofoil, using a function called Shape Function. Python programming was used to create a user interactive environment for geometry generation of aerofoil using NACA and Shape Function methodologies. Two aerofoils, NACA 0012 and NACA 1412, were generated using this function. Testing the accuracy of the Shape Function scheme was done by Linear Square Fitting using Python and CFD modelling the aerofoil in Fluent. NACA 0012 (symmetrical aerofoil) was better approximated using Shape Function than NACA 1412 (cambered aerofoil). The second part of the project involved comparing two turbulent models, k-ε and Spalart-Allmaras (SA), in Fluent by modelling the aerofoils NACA 0012 and NACA 1412 in conditions of Reynolds number of 3 × 106. It was shown that SA modelling is better for aerodynamic purpose. The experimental coefficient of lift (Cl) and coefficient of drag (Cd) were compared with empirical wind tunnel data for a range of angle of attack (AOA). As a further step, this project involved drawing and meshing 3D wings in Gambit. The 3D wing flow was solved and compared with 2D aerofoil section experimental results and wind tunnel data.

Keywords: CFD simulation, shape function, turbulent modelling, aerofoil

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7708 Correlation of Building Density toward Land Surface Temperature 2018 in Medan City

Authors: Andi Syahputra, R. H. Jatmiko, D. R. Hizbaron

Abstract:

Land surface temperature (LST) in an area is influenced by conditions of vegetation density, building density, and the number of inhabitants who live in the area. Medan City is one of the largest cities in Indonesia, with a high rate of change from vegetation to developed land. This study aims to identify the relationship between the percentage of building density and land surface temperature in Medan City. Pixel image analysis method is carried out to obtain the value of building density in pixel images of Landsat 8 images with the help of WorldView-2 satellite imagery. The results showed the highest land surface temperature in 2018 of 35, 4°C was found in Medan Perjuangan District, and the lowest was 22.5°C in Medan Belawan District. Building density samples with a density level of 889.17 m were also found in Medan Perjuangan District, while the lowest building density sample was found in Medan Timur District. Linear regression analysis of the effect of building density with land surface temperature obtained a correlation (R) was 0.64, and a coefficient of determination (R²) was 0.411 and modeling of building density based on the LST has a correlation (R), and a coefficient of determination (R²) was 0.72 with The RMSE obtained 0.853.

Keywords: land surface temperature, Landsat, imagery, building density, vegetation, density

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7707 Preparation and Performance of Polyphenylene Oxide-Based Anion Exchange Membrane for Vanadium Redox Flow Battery

Authors: Mi-Jung Park, Min-Hwa Lim, Ho-Young Jung

Abstract:

A polyphenylene oxide (PPO)-based anion exchange membrane based on the functionalization of bromomethylated PPO using 1-methylimdazole was fabricated for vanadium redox flow application. The imidazolium-bromomethylated PPO (Im-bPPO) showed lower permeability VO2+ ions (2.9×10⁻¹⁴ m²/sec), compared to Nafion 212 (2.3×10⁻¹² m²/sec) and FAP-450 (7.9×10⁻¹⁴ m²/sec). Even though the Im-bPPO membrane has higher permeability, the energy efficiency of the VRFB with the Im-bPPO membrane was slightly lower than that of Nafion and FAP-450. The Im-bPPO membrane exhibits good voltage efficiency compared to FAP-450 and Nafion 212 because of its better ion conductivity. The Im-bPPo membrane showed up good performance, but a decline in performance at later cycles was observed.

Keywords: anion exchange membranes, vanadium redox flow battery, polyphenylene oxide, energy efficiency (EE)

Procedia PDF Downloads 317
7706 Jungle Justice on Emotional Health Challenges among Lagosians

Authors: Aaron Akinloye

Abstract:

This research examined the influence of jungle justice as it affects the emotional health challenges among residents in Lagos metropolitan city. Descriptive survey research design was used along with the questionnaire as research instrument. Population for the study comprised residents in Yaba and Shomolu Communities of Lagos State, Nigeria. Accidental sampling technique was used to sample 300 Residents. Self-developed questionnaire was used to obtain data on the variables under investigation. Research instrument was validated following the face, content, and construct validation of the instrument. Thereafter, the reliability coefficient yielded 0.84. It is therefore concluded and recommended that; there is a significant influence of jungle justice on trauma among residents- df (298) t= 2.33, p< 0.05; there is a significant influence of jungle justice on pressure among residents- df (298) t= 2.16, p< 0.05: there is a significant influence of jungle justice on fear among residents- df (298) t= 2.20, p< 0.05; there is a significant influence of jungle justice on depression among residents- df (298) t= 2.14, p< 0.05. Recommendations were made that; there should be deliberate effort to implement comprehensive awareness campaigns to educate the residents on the detrimental effects of jungle justice on individuals and the community members as a whole; there should be an improvement in the effectiveness and efficiency of the existing law enforcement agencies in Lagos metropolitan city; development and implementation of support systems for victims of jungle justice, which include trauma, counselling, mental health services, and rehabilitation programmes; there should be proper review and revision of the legal framework to address the issue of jungle justice effectively.

Keywords: jungle justice, emotional health, depression, fear

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7705 Effects of Internet Addiction on Students’ Academic Performance among Some Tertiary Institutions in Oyo State, Nigeria

Authors: Mujidat Lola Olugbode

Abstract:

This study investigates the effects of internet addiction on academic performance among students in some tertiary institutions in Oyo State, Nigeria. A descriptive survey research design was adopted for the study. Two research questions and two hypotheses were answered and tested. The population of the study comprised of all students in five tertiary institutions in Oyo State, Nigeria. Simple random sampling technique was used to select 2550 participants (respondents) from the institutions used for the study, this constituted the sample for the study. The instruments used for data collection was a self-constructed questionnaire on Internet Addiction and Students Academic Performance (IAASAP). The reliability coefficient of the instrument was 0.77. Data collected were analyzed using frequency and percentages, Pearson Product Moment Correlation coefficient (PPMCC) and t-test analysis. The results showed that the students in tertiary institutions in Oyo State were occasionally addicted to internet use. The study also revealed a positive correlation between internet addiction and academic performance. The findings also showed that there was significant difference in the internet addiction between male and female Students. Based on the above findings, the researchers recommended among others that government, educators, parents, counselors, teachers should help redirect the internet use toward academics to ensure greater academic performance.

Keywords: internet, addiction, internet addiction, academic performance, tertiary institution, students

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7704 A Comparative Study of Self, Peer and Teacher Assessment Based on an English Writing Checklist

Authors: Xiaoting Shi, Xiaomei Ma

Abstract:

In higher education, students' self-assessment and peer assessment of compositions in writing classes can effectively improve their ability of evaluative judgment. However, students' self-assessment and peer assessment are not advocated by most teachers because of the significant difference in scoring compared with teacher assessment. This study used a multi-faceted Rasch model to explore whether an English writing checklist containing 30 descriptors can effectively improve rating consistency among self-assessment, peer assessment and teacher assessment. Meanwhile, a questionnaire was adopted to survey students’ and teachers’ attitudes toward self-assessment and peer assessment using the writing checklist. Results of the multi-faceted Rasch model analysis show that the writing checklist can effectively distinguish the students’ writing ability (separate coefficient = 2.05, separate reliability = 0.81, chi-square value (df = 32) = 123.4). Moreover, the results revealed that the checklist could improve rating consistency among self-assessment, peer assessment and teacher assessment. (separate coefficient = 1.71, separate reliability = 0.75, chi-square value (df=4) = 20.8). The results of the questionnaire showed that more than 85% of students and all teachers believed that the checklist had a good advantage in self-assessment and peer assessment, and they were willing to use the checklist to conduct self-assessment and peer assessment in class in the future.

Keywords: english writing, self-assessment, peer assessment, writing checklist

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7703 Rooibos Extract Antioxidants: In vitro Models to Assess Their Bioavailability

Authors: Ntokozo Dambuza, Maryna Van De Venter, Trevor Koekemoer

Abstract:

Oxidative stress contributes to the pathogenesis of many diseases and consequently antioxidant therapy has attracted much attention as a potential therapeutic strategy. Regardless of the quantities ingested, antioxidants need to reach the diseased tissues at concentrations sufficient to combat oxidative stress. Bioavailability is thus a defining criterion for the therapeutic efficacy of antioxidants. In addition, therapeutic antioxidants must possess biologically relevant characteristics which can target the specific molecular mechanisms responsible for disease related oxidative stress. While many chemical antioxidant assays are available to quantify antioxidant capacity, they relate poorly to the biological environment and provide no information as to the bioavailability. The present comparative study thus aims to characterise green and fermented rooibos extracts, well recognized for their exceptional antioxidant capacity, in terms of antioxidant bioavailability and efficacy in a disease relevant cellular setting. Chinese green tea antioxidant activity was also evaluated. Chemical antioxidant assays (FRAP, DPPH and ORAC) confirmed the potent antioxidant capacity of both green and fermented rooibos, with green rooibos possessing antioxidant activity superior to that of fermented rooibos and Chinese green tea. Bioavailability was assessed using the PAMPA assay and the results indicate that green and fermented rooibos have a permeation coefficient of 5.7 x 10-6 and 6.9 x 10-6 cm/s, respectively. Chinese green tea permeability coefficient was 8.5 x 10-6 cm/s. These values were comparable to those of rifampicin, which is known to have a high permeability across intestinal epithelium with a permeability coefficient of 5 x 10 -6 cm/s. To assess the antioxidant efficacy in a cellular context, U937 and red blood cells were pre-treated with rooibos and Chinese green tea extracts in the presence of a dye DCFH-DA and then exposed to oxidative stress. Green rooibos exhibited highest activity with an IC50 value of 29 μg/ml and 70 μg/ml, when U937 and red blood cells were exposed oxidative stress, respectively. Fermented rooibos and Chinese green tea had IC50 values of 61 μg/ml and 57 μg/ml for U937, respectively, and 221 μg/ml and 405 μg/ml for red blood cells, respectively. These results indicate that fermented and green rooibos extracts were able to permeate the U937 cells and red blood cell membrane and inhibited oxidation of DCFH-DA to a fluorescent DCF within the cells.

Keywords: rooibos, antioxidants, permeability, bioavailability

Procedia PDF Downloads 317