Search results for: sharpe ratio
3667 Low Power CMOS Amplifier Design for Wearable Electrocardiogram Sensor
Authors: Ow Tze Weng, Suhaila Isaak, Yusmeeraz Yusof
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The trend of health care screening devices in the world is increasingly towards the favor of portability and wearability, especially in the most common electrocardiogram (ECG) monitoring system. This is because these wearable screening devices are not restricting the patient’s freedom and daily activities. While the demand of low power and low cost biomedical system on chip (SoC) is increasing in exponential way, the front end ECG sensors are still suffering from flicker noise for low frequency cardiac signal acquisition, 50 Hz power line electromagnetic interference, and the large unstable input offsets due to the electrode-skin interface is not attached properly. In this paper, a high performance CMOS amplifier for ECG sensors that suitable for low power wearable cardiac screening is proposed. The amplifier adopts the highly stable folded cascode topology and later being implemented into RC feedback circuit for low frequency DC offset cancellation. By using 0.13 µm CMOS technology from Silterra, the simulation results show that this front end circuit can achieve a very low input referred noise of 1 pV/√Hz and high common mode rejection ratio (CMRR) of 174.05 dB. It also gives voltage gain of 75.45 dB with good power supply rejection ratio (PSSR) of 92.12 dB. The total power consumption is only 3 µW and thus suitable to be implemented with further signal processing and classification back end for low power biomedical SoC.Keywords: CMOS, ECG, amplifier, low power
Procedia PDF Downloads 2413666 The Reproducibility and Repeatability of Modified Likelihood Ratio for Forensics Handwriting Examination
Authors: O. Abiodun Adeyinka, B. Adeyemo Adesesan
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The forensic use of handwriting depends on the analysis, comparison, and evaluation decisions made by forensic document examiners. When using biometric technology in forensic applications, it is necessary to compute Likelihood Ratio (LR) for quantifying strength of evidence under two competing hypotheses, namely the prosecution and the defense hypotheses wherein a set of assumptions and methods for a given data set will be made. It is therefore important to know how repeatable and reproducible our estimated LR is. This paper evaluated the accuracy and reproducibility of examiners' decisions. Confidence interval for the estimated LR were presented so as not get an incorrect estimate that will be used to deliver wrong judgment in the court of Law. The estimate of LR is fundamentally a Bayesian concept and we used two LR estimators, namely Logistic Regression (LoR) and Kernel Density Estimator (KDE) for this paper. The repeatability evaluation was carried out by retesting the initial experiment after an interval of six months to observe whether examiners would repeat their decisions for the estimated LR. The experimental results, which are based on handwriting dataset, show that LR has different confidence intervals which therefore implies that LR cannot be estimated with the same certainty everywhere. Though the LoR performed better than the KDE when tested using the same dataset, the two LR estimators investigated showed a consistent region in which LR value can be estimated confidently. These two findings advance our understanding of LR when used in computing the strength of evidence in handwriting using forensics.Keywords: confidence interval, handwriting, kernel density estimator, KDE, logistic regression LoR, repeatability, reproducibility
Procedia PDF Downloads 1133665 Effect of Using PCMs and Transparency Rations on Energy Efficiency and Thermal Performance of Buildings in Hot Climatic Regions. A Simulation-Based Evaluation
Authors: Eda K. Murathan, Gulten Manioglu
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In the building design process, reducing heating and cooling energy consumption according to the climatic region conditions of the building are important issues to be considered in order to provide thermal comfort conditions in the indoor environment. Applying a phase-change material (PCM) on the surface of a building envelope is the new approach for controlling heat transfer through the building envelope during the year. The transparency ratios of the window are also the determinants of the amount of solar radiation gain in the space, thus thermal comfort and energy expenditure. In this study, a simulation-based evaluation was carried out by using Energyplus to determine the effect of coupling PCM and transparency ratio when integrated into the building envelope. A three-storey building, a 30m x 30m sized floor area and 10m x 10m sized courtyard are taken as an example of the courtyard building model, which is frequently seen in the traditional architecture of hot climatic regions. 8 zones (10m x10m sized) with 2 exterior façades oriented in different directions on each floor were obtained. The percentage of transparent components on the PCM applied surface was increased at every step (%30, %40, %50). For every zone differently oriented, annual heating, cooling energy consumptions, and thermal comfort based on the Fanger method were calculated. All calculations are made for the zones of the intermediate floor of the building. The study was carried out for Diyarbakır provinces representing the hot-dry climate region and Antalya representing the hot-humid climate region. The increase in the transparency ratio has led to a decrease in heating energy consumption but an increase in cooling energy consumption for both provinces. When PCM is applied to all developed options, It was observed that heating and cooling energy consumption decreased in both Antalya (6.06%-19.78% and %1-%3.74) and Diyarbakır (2.79%-3.43% and 2.32%-4.64%) respectively. When the considered building is evaluated under passive conditions for the 21st of July, which represents the hottest day of the year, it is seen that the user feels comfortable between 11 pm-10 am with the effect of night ventilation for both provinces.Keywords: building envelope, heating and cooling energy consumptions, phase change material, transparency ratio
Procedia PDF Downloads 1683664 Interest Charges and Sustainability Challenges: The Case of OECD Countries
Authors: Aime Philombe Zapji Ymele
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Servicing public debt is a significant budgetary burden. In the sense that the payment of interest charges is a liability on the balance sheet of the public budget and affects fiscal policy. Interest charges can sometimes become a burden if they crowd out private activities. In order to analyse and understand the determinants of the debt burden and its impact on the sustainability of public finances, the present work focuses on OECD countries. It is noted from the literature that the factors that determine interest charges are macroeconomic (inflation, GDP growth, and interest rates) and public finances (primary balance and public debt). After analysing a panel of 33 OECD countries and using ordinary least squares (OLS), we find that public debt, inflation, and long-term interest rates are positively correlated with interest charges. An increase in any of these variables leads to an increase in debt charges. On the other hand, a growth in GDP is negatively associated with interest charges. Indeed, an increase in GDP generates enough revenue to meet the repayment of debt charges. According to the empirical analysis, we can say that, despite the large and growing debt-to-GDP ratio of major OECD countries, interest charges are not a threat to the sustainability of public finances. However, it is important for these countries to reduce the ratio of public debt to GDP because, in the face of the many challenges (health, aging population, etc.) that are looming on the horizon, an increase in interest rates could bring with it considerable burdens that would threaten the budgetary balance of these states.Keywords: interest charges, sustainability, public debt, interest rates
Procedia PDF Downloads 1133663 Diagnostic Performance of Mean Platelet Volume in the Diagnosis of Acute Myocardial Infarction: A Meta-Analysis
Authors: Kathrina Aseanne Acapulco-Gomez, Shayne Julieane Morales, Tzar Francis Verame
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Mean platelet volume (MPV) is the most accurate measure of the size of platelets and is routinely measured by most automated hematological analyzers. Several studies have shown associations between MPV and cardiovascular risks and outcomes. Although its measurement may provide useful data, MPV remains to be a diagnostic tool that is yet to be included in routine clinical decision making. The aim of this systematic review and meta-analysis is to determine summary estimates of the diagnostic accuracy of mean platelet volume for the diagnosis of myocardial infarction among adult patients with angina and/or its equivalents in terms of sensitivity, specificity, diagnostic odds ratio, and likelihood ratios, and to determine the difference of the mean MPV values between those with MI and those in the non-MI controls. The primary search was done through search in electronic databases PubMed, Cochrane Review CENTRAL, HERDIN (Health Research and Development Information Network), Google Scholar, Philippine Journal of Pathology, and Philippine College of Physicians Philippine Journal of Internal Medicine. The reference list of original reports was also searched. Cross-sectional, cohort, and case-control articles studying the diagnostic performance of mean platelet volume in the diagnosis of acute myocardial infarction in adult patients were included in the study. Studies were included if: (1) CBC was taken upon presentation to the ER or upon admission (within 24 hours of symptom onset); (2) myocardial infarction was diagnosed with serum markers, ECG, or according to accepted guidelines by the Cardiology societies (American Heart Association (AHA), American College of Cardiology (ACC), European Society of Cardiology (ESC); and, (3) if outcomes were measured as significant difference AND/OR sensitivity and specificity. The authors independently screened for inclusion of all the identified potential studies as a result of the search. Eligible studies were appraised using well-defined criteria. Any disagreement between the reviewers was resolved through discussion and consensus. The overall mean MPV value of those with MI (9.702 fl; 95% CI 9.07 – 10.33) was higher than in those of the non-MI control group (8.85 fl; 95% CI 8.23 – 9.46). Interpretation of the calculated t-value of 2.0827 showed that there was a significant difference in the mean MPV values of those with MI and those of the non-MI controls. The summary sensitivity (Se) and specificity (Sp) for MPV were 0.66 (95% CI; 0.59 - 0.73) and 0.60 (95% CI; 0.43 – 0.75), respectively. The pooled diagnostic odds ratio (DOR) was 2.92 (95% CI; 1.90 – 4.50). The positive likelihood ratio of MPV in the diagnosis of myocardial infarction was 1.65 (95% CI; 1.20 – 22.27), and the negative likelihood ratio was 0.56 (95% CI; 0.50 – 0.64). The intended role for MPV in the diagnostic pathway of myocardial infarction would perhaps be best as a triage tool. With a DOR of 2.92, MPV values can discriminate between those who have MI and those without. For a patient with angina presenting with elevated MPV values, it is 1.65 times more likely that he has MI. Thus, it is implied that the decision to treat a patient with angina or its equivalents as a case of MI could be supported by an elevated MPV value.Keywords: mean platelet volume, MPV, myocardial infarction, angina, chest pain
Procedia PDF Downloads 743662 Qualitative and Quantitative Traits of Processed Farmed Fish in N. W. Greece
Authors: Cosmas Nathanailides, Fotini Kakali, Kostas Karipoglou
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The filleting yield and the chemical composition of farmed sea bass (Dicentrarchus labrax); rainbow trout (Oncorynchus mykiss) and meagre (Argyrosomus regius) was investigated in farmed fish in NW Greece. The results provide an estimate of the quantity of fish required to produce one kilogram of fillet weight, an estimation which is required for the operational management of fish processing companies. Furthermore in this work, the ratio of feed input required to produce one kilogram of fish fillet (FFCR) is presented for the first time as a useful indicator of the ecological footprint of consuming farmed fish. The lowest lipid content appeared in meagre (1,7%) and the highest in trout (4,91%). The lowest fillet yield and fillet yield feed conversion ratio (FYFCR) was in meagre (FY=42,17%, FFCR=2,48), the best fillet yield (FY=53,8%) and FYFCR (2,10) was exhibited in farmed rainbow trout. This research has been co-financed by the European Union (European Social Fund – ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) - Research Funding Program: ARCHIMEDES III. Investing in knowledge society through the European Social Fund.Keywords: farmed fish, flesh quality, filleting yield, lipid
Procedia PDF Downloads 3023661 Optimization of Pregelatinized Taro Boloso-I Starch as a Direct Compression Tablet Excipient
Authors: Tamrat Balcha Balla
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Background: Tablets are still the most preferred means of drug delivery. The search for new and improved direct compression tablet excipients is an area of research focus. Taro Boloso-I is a variety of Colocasia esculenta (L. Schott) yielding 67% more than the other varieties (Godare) in Ethiopia. This study aimed to enhance the flowability while keeping the compressibility and compactibility of the pregelatinized Taro Boloso-I starch. Methods: Central composite design was used for the optimization of two factors which were the temperature and duration of pregelatinization against 5 responses. The responses were angle of repose, Hausner ratio, Kawakita compressibility index, mean yield pressure and tablet breaking force. Results and Discussions: An increase in both temperature and time resulted in decrease in the angle of repose. The increase in temperature was shown to decrease the Hausner ratio and to decrease the Kawakita compressibility index. The mean yield pressure was observed to increase with increasing levels of both temperature and time. The pregelatinized (optimized) Taro Boloso-I starch could show desired flow property and compressibility. Conclusions: Pregelatinized Taro Boloso - I starch could be regarded as a potential direct compression excipient in terms of flowability, compressibility and compactibility.Keywords: starch, compression, pregelatinization, Taro Boloso-I
Procedia PDF Downloads 1033660 Prominent Lipid Parameters Correlated with Trunk-to-Leg and Appendicular Fat Ratios in Severe Pediatric Obesity
Authors: Mustafa M. Donma, Orkide Donma
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The examination of both serum lipid fractions and body’s lipid composition are quite informative during the evaluation of obesity stages. Within this context, alterations in lipid parameters are commonly observed. The variations in the fat distribution of the body are also noteworthy. Total cholesterol (TC), triglycerides (TRG), low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol (HDL-C) are considered as the basic lipid fractions. Fat deposited in trunk and extremities may give considerable amount of information and different messages during discrete health states. Ratios are also derived from distinct fat distribution in these areas. Trunk-to-leg fat ratio (TLFR) and trunk-to-appendicular fat ratio (TAFR) are the most recently introduced ratios. In this study, lipid fractions and TLFR, as well as TAFR, were evaluated, and the distinctions among healthy, obese (OB), and morbid obese (MO) groups were investigated. Three groups [normal body mass index (N-BMI), OB, MO] were constituted from a population aged 6 to 18 years. Ages and sexes of the groups were matched. The study protocol was approved by the Non-interventional Ethics Committee of Tekirdag Namik Kemal University. Written informed consent forms were obtained from the parents of the participants. Anthropometric measurements (height, weight, waist circumference, hip circumference, head circumference, neck circumference) were obtained and recorded during the physical examination. Body mass index values were calculated. Total, trunk, leg, and arm fat mass values were obtained by TANITA Bioelectrical Impedance Analysis. These values were used to calculate TLFR and TAFR. Systolic (SBP) and diastolic blood pressures (DBP) were measured. Routine biochemical tests including TC, TRG, LDL-C, HDL-C, and insulin were performed. Data were evaluated using SPSS software. p value smaller than 0.05 was accepted as statistically significant. There was no difference among the age values and gender ratios of the groups. Any statistically significant difference was not observed in terms of DBP, TLFR as well as serum lipid fractions. Higher SBP values were measured both in OB and MO children than those with N-BMI. TAFR showed a significant difference between N-BMI and OB groups. Statistically significant increases were detected between insulin values of N-BMI group and OB as well as MO groups. There were bivariate correlations between LDL and TLFR (r=0.396; p=0.037) as well as TAFR values (r=0.413; p=0.029) in MO group. When adjusted for SBP and DBP, partial correlations were calculated as (r=0.421; p=0.032) and (r=0.438; p=0.025) for LDL-TLFR as well as LDL-TAFR, respectively. Much stronger partial correlations were obtained for the same couples (r=0.475; p=0.019 and r=0.473; p=0.020, respectively) upon controlling for TRG and HDL-C. Much stronger partial correlations observed in MO children emphasize the potential transition from morbid obesity to metabolic syndrome. These findings have concluded that LDL-C may be suggested as a discriminating parameter between OB and MO children.Keywords: children, lipid parameters, obesity, trunk-to-leg fat ratio, trunk-to-appendicular fat ratio
Procedia PDF Downloads 1053659 Effect of Microencapsulated Butyric Acid Supplementation on Growth Performance, Ileal Digestibility of Protein, Gut Health and Immunity in Broilers
Authors: Saeed Ahmed, Muhammad Imran, Yasir Allah Ditta, Shahid Mehmood, Zahid Rasool
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A study was conducted to investigate the effect of different levels of microencapsulated butyric (MEB) on growth performance, gut health and immunity in commercial broiler chickens. In total, 336 day-old Hubbard classic broilers chicks were randomly assigned to 4 dietary treatments (Control, 0.25, 0.35 and 0.45g/kg of butyric acid) under completely randomized design. Each treatment was replicated 3 times with 28 birds in each replicate. Feed intake, body weight gain, feed conversion ratio, intestinal morphology, apparent ileal digestibility of protein and immunity parameters were evaluated. At the end of the experiment (35-d) 3 birds/replicate in each group were randomly selected and slaughtered to collect blood, duodenal samples and ileal digesta. The data were analyzed by using ANOVA technique. The results indicated improved body weight gain (P = 0.0222), feed conversion ratio (P = 0.0056), duodenal villus height (P = 0.0512), AID (P = 0.0098) antibody titer against Newcastle disease improved (P = 0.0326). Treatments remained unresponsive with respect to feed intake (P = 0.9685).Keywords: butyric acid, broilers, gut health, ileal digestibility
Procedia PDF Downloads 3143658 Characteristics and Quality of Chilean Abalone Undergoing Different Drying Emerging Technologies
Authors: Mario Pérez-Won, Anais Palma-Acevedo, Luis González-Cavieres, Roberto Lemus-Mondaca, Gipsy Tabilo-Munizaga
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The Chilean abalone (Concholepas Concholepas) is a gastropod mollusk; it has a high commercial value due to the qualities of its meat, especially hardness, as a critical acceptance parameter. However, its main problem is its short shelf-life which is usually extended using traditional technologies with high energy consumption. Therefore, applying different technologies for the pre-treatment and drying process is necessary. In this research, pulsed electric field (PEF) was used as a pre-treatment for vacuum microwave drying (VMD), freeze-drying (FD), and hot-air drying (HAD). Drying conditions and characteristics were set according to previous experiments. The Drying samples were analyzed in terms of physical quality (color, texture, microstructure, and rehydration capacity), protein quality (degree of hydrolysis and computer protein efficiency ratio), and energy parameters. Regarding quality, the treatment that obtained lower harness was PEF+FD (195 N ± 10), the lowest change of color was for treatment PEF+VMD (ΔE: 17 ± 1.5), and the best rehydration capacity was for treatment PEF+VMD (1.2 h for equilibrium). For protein quality, the highest Computer-Protein Efficiency Ratio was the sample 2.0 kV/ cm of PEF (index of 4.18 ± 0.26 at the end of the digestion). Moreover, about energetic consumption, results show that VMD decreases the drying process by 97% whether PEF was used or not. Consequently, it is possible to conclude that using PEF as a pre-treatment for VMD and FD treatments has advantages that must be used following the consumer’s needs or preferences.Keywords: chilean abalone, freeze-drying, proteins, pulsed electric fields
Procedia PDF Downloads 1013657 Interest Charges and Sustainability Challenges: The Case of OECD Countries
Authors: Zapji Ymele Aime Philombe
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Servicing public debt is a significant budgetary burden in the sense that the payment of interest charges is a liability on the balance sheet of the public budget and affects fiscal policy. Interest charges can sometimes become a burden if they crowd out private activities. In order to analyse and understand the determinants of the debt burden and its impact on the sustainability of public finances, the present work focuses on OECD countries. It is noted from the literature that the factors that determine interest charges are macroeconomic (inflation, GDP growth and interest rates) and public finances (primary balance and public debt). After analysing a panel of 33 OECD countries and using ordinary least squares (OLS), we find that public debt, inflation and long-term interest rates are positively correlated with interest charges. An increase in any of these variables leads to an increase in debt charges. On the other hand, a growth in GDP is negatively associated with interest charges. Indeed, an increase in GDP generates enough revenue to meet the repayment of debt charges. According to the empirical analysis, we can say that, despite the large and growing debt-to-GDP ratio of major OECD countries, interest charges are not a threat to the sustainability of public finances. However, it is important for these countries to reduce the ratio of public debt to GDP because, in the face of the many challenges (health, aging population, etc.) that are looming on the horizon, an increase in interest rates could bring with it considerable burdens that would threaten the budgetary balance of these states.Keywords: interests charges, public debt, sustainability, interest rates
Procedia PDF Downloads 1143656 Comparative Economic Analysis of Floating Photovoltaic Systems Using a Synthesis Approach
Authors: Ching-Feng Chen
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The floating photovoltaic (FPV) system highlights economic benefits and energy performance to carbon dioxide (CO₂) discharges. Due to land resource scarcity and many negligent water territories, such as reservoirs, dams, and lakes in Japan and Taiwan, both countries are actively developing FPV and responding to the pricing of the emissions trading systems (ETS). This paper performs a case study through a synthesis approach to compare the economic indicators between the FPVs of Taiwan’s Agongdian Reservoir and Japan’s Yamakura Dam. The research results show that the metrics of the system capacity, installation costs, bank interest rates, and ETS and Electricity Bills affect FPV operating gains. In the post-Feed-In-Tariff (FIT) phase, investing in FPV in Japan is more profitable than in Taiwan. The former’s positive net present value (NPV), eminent internal rate of return (IRR) (11.6%), and benefit-cost ratio (BCR) above 1 (2.0) at the discount rate of 10% indicate that investing the FPV in Japan is more favorable than in Taiwan. In addition, the breakeven point is modest (about 61.3%.). The presented methodology in the study helps investors evaluate schemes’ pros and cons and determine whether a decision is beneficial while funding PV or FPV projects.Keywords: carbon border adjustment mechanism, floating photovoltaic, emissions trading systems, net present value, internal rate of return, benefit-cost ratio
Procedia PDF Downloads 613655 Flourishing in Marriage among Arab Couples in Israel: The Impact of Capitalization Support and Accommodation on Positive and Negative Affect
Authors: Niveen Hassan-Abbas, Tammie Ronen-Rosenbaum
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Background and purpose: 'Flourishing in marriage' is a concept refers to married individuals’ high positivity ratio regarding their marriage, namely greater reported positive than negative emotions. The study proposes a different approach to marriage which emphasizes the place of the individual himself as largely responsible for his personal flourishing within marriage. Accordingly, the individual's desire to preserve and strengthen his marriage largely determines the marital behavior in a way that will contribute to his marriage success (Actor Effect), regardless the contribution of his or her partner to his marriage success (Partner Effect). Another assumption was that flourishing in marriage could be achieved by two separate processes, where capitalization support increases the positive marriage's evaluations and accommodation decreases the negative one. A theoretical model was constructed, whereby individuals who were committed to their marriage were hypothesized as employing self-control skills by way of two dynamic processes. First, individual’s higher degree of 'capitalization supportive responses' - supportive responses to the partner's sharing of positive personal experiences - was hypothesized as increasing one’s positive evaluations of marriage and thereby one’s positivity ratio. Second, individual’s higher degree of 'accommodation' responses - the ability during conflict situations to control the impulse to respond destructively and instead to respond constructively - was hypothesized as decreasing one’s negative evaluations of marriage and thereby increasing one’s positivity ratio. Methods: Participants were 156 heterosexual Arab couples from different regions of Israel. The mean period of marriage was 10.19 (SD=7.83), ages were 31.53 years for women (SD=8.12) and 36.80 years for men (SD=8.07). Years of education were 13.87 for women (SD=2.84) and 13.23 years for men (SD=3.45). Each participant completed seven questionnaires: socio-demographic, self-control skills, commitment, capitalization support, accommodation, marital quality, positive and negative affect. Using statistical analyses adapted to dyadic research design, firstly descriptive statistics were calculated and preliminary tests were performed. Next, dyadic model based on the Actor-Partner Interdependence Model (APIM) were tested using structural equation modeling (SEM). Results: The assumption according to which flourishing in marriage can be achieved by two processes was confirmed. All of the Actor Effect hypotheses were confirmed. Participants with higher self-control used more capitalization support and accommodation responses. Among husbands, unlike wives, these correlations were stronger when the individual's commitment level was higher. More capitalization supportive responses were found to increase positive evaluations of marriage, and greater spousal accommodation was found to decrease negative evaluations of marriage. High positive evaluations and low negative evaluations were found to increase positivity ratio. Not according to expectation, four partner effect paths were found significant. Conclusions and Implications: The present findings coincide with the positive psychology approach that emphasizes human strengths. The uniqueness of this study is its proposal that individuals are largely responsible for their personal flourishing in marriage. This study demonstrated that marital flourishing can be achieved by two processes, where capitalization increases the positive and accommodation decreases the negative. Practical implications include the need to construct interventions that enhance self-control skills for employment of capitalizing responsiveness and accommodation processes.Keywords: accommodation, capitalization support, commitment, flourishing in marriage, positivity ratio, self-control skills
Procedia PDF Downloads 1533654 Determinants of Diarrhoea Prevalence Variations in Mountainous Informal Settlements of Kigali City, Rwanda
Authors: Dieudonne Uwizeye
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Introduction: Diarrhoea is one of the major causes of morbidity and mortality among communities living in urban informal settlements of developing countries. It is assumed that mountainous environment introduces variations of the burden among residents of the same settlements. Design and Objective: A cross-sectional study was done in Kigali to explore the effect of mountainous informal settlements on diarrhoea risk variations. Data were collected among 1,152 households through household survey and transect walk to observe the status of sanitation. The outcome variable was the incidence of diarrhoea among household members of any age. The study used the most knowledgeable person in the household as the main respondent. Mostly this was the woman of the house as she was more likely to know the health status of every household member as she plays various roles: mother, wife, and head of the household among others. The analysis used cross tabulation and logistic regression analysis. Results: Results suggest that risks for diarrhoea vary depending on home location in the settlements. Diarrhoea risk increased as the distance from the road increased. The results of the logistic regression analysis indicate the adjusted odds ratio of 2.97 with 95% confidence interval being 1.35-6.55 and 3.50 adjusted odds ratio with 95% confidence interval being 1.61-7.60 in level two and three respectively compared with level one. The status of sanitation within and around homes was also significantly associated with the increase of diarrhoea. Equally, it is indicated that stable households were less likely to have diarrhoea. The logistic regression analysis indicated the adjusted odds ratio of 0.45 with 95% confidence interval being 0.25-0.81. However, the study did not find evidence for a significant association between diarrhoea risks and household socioeconomic status in the multivariable model. It is assumed that environmental factors in mountainous settings prevailed. Households using the available public water sources were more likely to have diarrhoea in their households. Recommendation: The study recommends the provision and extension of infrastructure for improved water, drainage, sanitation and wastes management facilities. Equally, studies should be done to identify the level of contamination and potential origin of contaminants for water sources in the valleys to adequately control the risks for diarrhoea in mountainous urban settings.Keywords: urbanisation, diarrhoea risk, mountainous environment, urban informal settlements in Rwanda
Procedia PDF Downloads 1623653 Study of Chemical State Analysis of Rubidium Compounds in Lα, Lβ₁, Lβ₃,₄ and Lγ₂,₃ X-Ray Emission Lines with Wavelength Dispersive X-Ray Fluorescence Spectrometer
Authors: Harpreet Singh Kainth
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Rubidium salts have been commonly used as an electrolyte to improve the efficiency cycle of Li-ion batteries. In recent years, it has been implemented into the large scale for further technological advances to improve the performance rate and better cyclability in the batteries. X-ray absorption spectroscopy (XAS) is a powerful tool for obtaining the information in the electronic structure which involves the chemical state analysis in the active materials used in the batteries. However, this technique is not well suited for the industrial applications because it needs a synchrotron X-ray source and special sample file for in-situ measurements. In contrast to this, conventional wavelength dispersive X-ray fluorescence (WDXRF) spectrometer is nondestructive technique used to study the chemical shift in all transitions (K, L, M, …) and does not require any special pre-preparation planning. In the present work, the fluorescent Lα, Lβ₁ , Lβ₃,₄ and Lγ₂,₃ X-ray spectra of rubidium in different chemical forms (Rb₂CO₃ , RbCl, RbBr, and RbI) have been measured first time with high resolution wavelength dispersive X-ray fluorescence (WDXRF) spectrometer (Model: S8 TIGER, Bruker, Germany), equipped with an Rh anode X-ray tube (4-kW, 60 kV and 170 mA). In ₃₇Rb compounds, the measured energy shifts are in the range (-0.45 to - 1.71) eV for Lα X-ray peak, (0.02 to 0.21) eV for Lβ₁ , (0.04 to 0.21) eV for Lβ₃ , (0.15 to 0.43) eV for Lβ₄ and (0.22 to 0.75) eV for Lγ₂,₃ X-ray emission lines. The chemical shifts in rubidium compounds have been measured by considering Rb₂CO₃ compounds taking as a standard reference. A Voigt function is used to determine the central peak position of all compounds. Both positive and negative shifts have been observed in L shell emission lines. In Lα X-ray emission lines, all compounds show negative shift while in Lβ₁, Lβ₃,₄, and Lγ₂,₃ X-ray emission lines, all compounds show a positive shift. These positive and negative shifts result increase or decrease in X-ray energy shifts. It looks like that ligands attached with central metal atom attract or repel the electrons towards or away from the parent nucleus. This pulling and pushing character of rubidium affects the central peak position of the compounds which causes a chemical shift. To understand the chemical effect more briefly, factors like electro-negativity, line intensity ratio, effective charge and bond length are responsible for the chemical state analysis in rubidium compounds. The effective charge has been calculated from Suchet and Pauling method while the line intensity ratio has been calculated by calculating the area under the relevant emission peak. In the present work, it has been observed that electro-negativity, effective charge and intensity ratio (Lβ₁/Lα, Lβ₃,₄/Lα and Lγ₂,₃/Lα) are inversely proportional to the chemical shift (RbCl > RbBr > RbI), while bond length has been found directly proportional to the chemical shift (RbI > RbBr > RbCl).Keywords: chemical shift in L emission lines, bond length, electro-negativity, effective charge, intensity ratio, Rubidium compounds, WDXRF spectrometer
Procedia PDF Downloads 4973652 A Two-Pronged Truncated Deferred Sampling Plan for Log-Logistic Distribution
Authors: Braimah Joseph Odunayo, Jiju Gillariose
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This paper is aimed at developing a sampling plan that uses information from precedent and successive lots for lot disposition with a pretention that the life-time of a particular product assumes a Log-logistic distribution. A Two-pronged Truncated Deferred Sampling Plan (TTDSP) for Log-logistic distribution is proposed when the testing is truncated at a precise time. The best possible sample sizes are obtained under a given Maximum Allowable Percent Defective (MAPD), Test Suspension Ratios (TSR), and acceptance numbers (c). A formula for calculating the operating characteristics of the proposed plan is also developed. The operating characteristics and mean-ratio values were used to measure the performance of the plan. The findings of the study show that: Log-logistic distribution has a decreasing failure rate; furthermore, as mean-life ratio increase, the failure rate reduces; the sample size increase as the acceptance number, test suspension ratios and maximum allowable percent defective increases. The study concludes that the minimum sample sizes were smaller, which makes the plan a more economical plan to adopt when cost and time of production are costly and the experiment being destructive.Keywords: consumers risk, mean life, minimum sample size, operating characteristics, producers risk
Procedia PDF Downloads 1293651 Wet Flue Gas Desulfurization Using a New O-Element Design Which Replaces the Venturi Scrubber
Authors: P. Lestinsky, D. Jecha, V. Brummer, P. Stehlik
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Scrubbing by a liquid spraying is one of the most effective processes used for removal of fine particles and soluble gas pollutants (such as SO2, HCl, HF) from the flue gas. There are many configurations of scrubbers designed to provide contact between the liquid and gas stream for effectively capturing particles or soluble gas pollutants, such as spray plates, packed bed towers, jet scrubbers, cyclones, vortex and venturi scrubbers. The primary function of venturi scrubber is the capture of fine particles as well as HCl, HF or SO2 removal with effect of the flue gas temperature decrease before input to the absorption column. In this paper, sulfur dioxide (SO2) from flue gas was captured using new design replacing venturi scrubber (1st degree of wet scrubbing). The flue gas was prepared by the combustion of the carbon disulfide solution in toluene (1:1 vol.) in the flame in the reactor. Such prepared flue gas with temperature around 150 °C was processed in designed laboratory O-element scrubber. Water was used as absorbent liquid. The efficiency of SO2 removal, pressure drop and temperature drop were measured on our experimental device. The dependence of these variables on liquid-gas ratio was observed. The average temperature drop was in the range from 150 °C to 40 °C. The pressure drop was increased with increasing of a liquid-gas ratio, but not as much as for the common venturi scrubber designs. The efficiency of SO2 removal was up to 70 %. The pressure drop of our new designed wet scrubber is similar to commonly used venturi scrubbers; nevertheless the influence of amount of the liquid on pressure drop is not so significant.Keywords: desulphurization, absorption, flue gas, modeling
Procedia PDF Downloads 3883650 Preparation and Characterization of a Nickel-Based Catalyst Supported by Silica Promoted by Cerium for the Methane Steam Reforming Reaction
Authors: Ali Zazi, Ouiza Cherifi
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Natural gas currently represents a raw material of choice for the manufacture of a wide range of chemical products via synthesis gas, among the routes of transformation of methane into synthesis gas The reaction of the oxidation of methane by gas vapor 'water. This work focuses on the study of the effect of cerieum on the nickel-based catalyst supported by silica for the methane vapor reforming reaction, with a variation of certain parameters of the reaction. The reaction temperature, the H₂O / CH₄ ratio and the flow rate of the reaction mixture (CH₄-H₂O). Two catalysts were prepared by impregnation of Degussa silica with a solution of nickel nitrates and a solution of cerium nitrates [Ni (NO₃) 2 6H₂O and Ce (NO₃) 3 6H₂O] so as to obtain the 1.5% nickel concentrations. For both catalysts and plus 1% cerium for the second catalyst. These Catalysts have been characterized by physical and chemical analysis techniques: BET technique, Atomic Absorption, IR Spectroscopy, X-ray diffraction. These characterizations indicated that the nitrates had impregnated the silica. And that the NiO and Ce₂O3 phases are present and Ni°(after reaction). The BET surface of the silica decreases without being affected. The catalytic tests carried out on the two catalysts for the steam reforming reactions show that the addition of cerium to the nickel improves the catalytic performances of the nickel. And that these performances also depend on the parameters of the reaction, namely the temperature, the rate of the reaction mixture, and the ratio (H₂O / CH₄).Keywords: heterogeneous catalysis, steam reforming, Methane, Nickel, Cerium, synthesis gas, hydrogen
Procedia PDF Downloads 1513649 Quantum Sieving for Hydrogen Isotope Separation
Authors: Hyunchul Oh
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One of the challenges in modern separation science and technology is the separation of hydrogen isotopes mixtures since D2 and H2 consist of almost identical size, shape and thermodynamic properties. Recently, quantum sieving of isotopes by confinement in narrow space has been proposed as an alternative technique. Despite many theoretical suggestions, however, it has been difficult to discover a feasible microporous material up to now. Among various porous materials, the novel class of microporous framework materials (COFs, ZIFs and MOFs) is considered as a promising material class for isotope sieving due to ultra-high porosity and uniform pore size which can be tailored. Hence, we investigate experimentally the fundamental correlation between D2/H2 molar ratio and pore size at optimized operating conditions by using different ultramicroporous frameworks. The D2/H2 molar ratio is strongly depending on pore size, pressure and temperature. An experimentally determined optimum pore diameter for quantum sieving lies between 3.0 and 3.4 Å which can be an important guideline for designing and developing feasible microporous frameworks for isotope separation. Afterwards, we report a novel strategy for efficient hydrogen isotope separation at technologically relevant operating pressure through the development of quantum sieving exploited by the pore aperture engineering. The strategy involves installation of flexible components in the pores of the framework to tune the pore surface.Keywords: gas adsorption, hydrogen isotope, metal organic frameworks(MOFs), quantum sieving
Procedia PDF Downloads 2583648 Transesterification of Refined Palm Oil to Biodiesel in a Continuous Spinning Disc Reactor
Authors: Weerinda Appamana, Jirapong Keawkoon, Yamonporn Pacthong, Jirathiti Chitsanguansuk, Yanyong Sookklay
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In the present work, spinning disc reactor has been used for the intensification of synthesis of biodiesel from refined palm oil (RPO) based on the transesterification reaction. Experiments have been performed using different spinning disc surface and under varying operating parameters viz. molar ratio of oil to methanol (over the range of 1:4.5–1:9), rotational speed (over the range of 500–2,000 rpm), total flow rate (over the range of 260-520 ml/min), and KOH catalyst loading of 1.50% by weight of oil. Maximum FAME (fatty acid methyl esters) yield (97.5 %) of biodiesel from RPO was obtained at oil to methanol ratio of 1:6, temperature of 60 °C, and rotational speed of 1500 rpm and flow rate of 520 mL/min using groove disc at KOH catalyst loading of 1.5 wt%. Also, higher yield efficiency (biodiesel produced per unit energy consumed) was obtained for using the spinning disc reactor based approach as compared to the ultrasound hydrodynamic cavitation and conventional mechanical stirrer reactors. It obviously offers a significant reduction in the reaction time for the transesterification, especially when compared with the reaction time of 90 minutes required for the conventional mechanical stirrer. It can be concluded that the spinning disk reactor is a promising alternative method for continuous biodiesel production.Keywords: spinning disc reactor, biodiesel, process intensification, yield efficiency
Procedia PDF Downloads 1473647 Contribution to the Hydrogeochemical Investigations on the Wajid Aquifer System, Southwestern Part of Saudi Arabia
Authors: Mohamed Ahmed, Ezat Korany, Abdelaziz Al Basam, Osama Kasem
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The arid climate, low rate of precipitations and population reflect the increasing of groundwater uses as the main source of water in Saudi Arabia. The Wajid Aquifer System represents a regional groundwater aquifer system along the edge of the crystalline Arabian Shield near the southwestern tip of the Arabian Peninsula. The aquifer extends across the border of Saudi Arabia and Yemen from the Asir –Yemen Highlands to the Rub al Khali Depression and possibly to the Gulf coast (at the southwestern tip). The present work is representing a hydrogeochemical investigation on the Wajid Aquifer System. The studied area is being classified into three zones. The 1st zone is West of Wadi Ad Dawasir (Northern part of the studied area), the 2nd is Najran-Asir Zone (southern part of the studied area), and the 3rd zone is the intermediate -central zone (occupying the central area between the last two zones). The groundwater samples were collected and chemically analyzed for physicochemical properties such as pH, electrical conductivity, total hardness (TH), alkalinity (pH), total dissolved solids (TDS), major ions (Ca2+, Mg2+, Na+, K+, HCO3-, SO42- and Cl-), and trace elements. Some parameters such as sodium adsorption ratio (SAR), soluble sodium percentage (Na%), potential salinity, residual sodium carbonate, Kelly's ratio, permeability index and Gibbs ratio, hydrochemical coefficients, hydrochemical formula, ion dominance, salt combinations and water types were also calculated in order to evaluate the quality of the groundwater resources in the selected areas for different purposes. The distribution of the chemical constituents and their interrelationships are illustrated by different hydrochemical graphs. Groundwater depths and the depth to water were measured to study the effect of discharge on both the water level and the salinity of the studied groundwater wells. A detailed comparison between the three studied zones according to the variations shown by the chemical and field investigations are discussed in detailed within the work.Keywords: Najran-Asir, Wadi Ad Dawasir, Wajid Aquifer System, effect of discharge
Procedia PDF Downloads 1203646 A Kinetic Study on Recovery of High-Purity Rutile TiO₂ Nanoparticles from Titanium Slag Using Sulfuric Acid under Sonochemical Procedure
Authors: Alireza Bahramian
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High-purity TiO₂ nanoparticles (NPs) with size ranging between 50 nm and 100 nm are synthesized from titanium slag through sulphate route under sonochemical procedure. The effect of dissolution parameters such as the sulfuric acid/slag weight ratio, caustic soda concentration, digestion temperature and time, and initial particle size of the dried slag on the extraction efficiency of TiO₂ and removal of iron are examined. By optimizing the digestion conditions, a rutile TiO₂ powder with surface area of 42 m²/g and mean pore diameter of 22.4 nm were prepared. A thermo-kinetic analysis showed that the digestion temperature has an important effect, while the acid/slag weight ratio and initial size of the slag has a moderate effect on the dissolution rate. The shrinking-core model including both chemical surface reaction and surface diffusion is used to describe the leaching process. A low value of activation energy, 38.12 kJ/mol, indicates the surface chemical reaction model is a rate-controlling step. The kinetic analysis suggested a first order reaction mechanism with respect to the acid concentrations.Keywords: TiO₂ nanoparticles, titanium slag, dissolution rate, sonochemical method, thermo-kinetic study
Procedia PDF Downloads 2503645 Evaluation of Surface Water and Groundwater Quality in Parts of Umunneochi Southeast, Nigeria
Authors: Joshua Chima Chizoba, Wisdom Izuchukwu Uzoma, Elizabeth Ifeyiwa Okoyeh
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Water cannot be optimally used and sustained unless the quality is periodically assessed. The study area Umunneochi and environs are located in south eastern part of Nigeria. It stretches geographically from latitudes 50501N to 60000N and longitudes 70201E to 70301. The major geologic formations in the area include the Asu River group, Nkporo Shale, and Ajali Sandstone. The aim of this study is to evaluate the hydrochemical characteristics of surface and ground water sources in parts of Umunneochi and environs in order to establish portability of the water sources for drinking, domestic and irrigation purposes. A total of 15 samples were collected randomly from streams, springs and wells. The samples were analyzed for physicochemical parameters and heavy metals using handheld digital kits, photometer, titration method and Atomic Absorption Spectrophotometer (AAS) following acceptable standards. The obtained analytical data were interpreted, and results were compared with World Health Organization (WHO) standard. The concentration of pH, SO42-and Cl- range from 5.81 mg/l – 6.07 mg/l, 41.93 mg/l – 142.95 mg/l and 20.00 mg/l – 111 mg/l respectively, while Pb and Zn revealed a relative low mean concentration of 0.14 mg/l and 0.40 mg/l, which are all within (WHO) permissible limits except pH. About 27% of the samples are moderately hard. This is attributed to the mining activities in the areas. The abundance of cations and anions in the area are in the order of K+>Na+>Mg2+>Ca2+ and SO4->Cl->HCO3->NO3-, respectively. Chloride, bicarbonate, and nitrate are all within the permissible limits. 13.33% of the total samples contain Sulphate above the standard permissible limits. The values of calculated Water Quality Index (WQI) are less than 50 indicating excellent water. The predominant water-type in the study area is Na-Cl water type and mixed Ca-Mg-Cl water type based on the sample plots on the Piper diagram. The Sodium Absorption Ratio (SAR) calculations showed excellent water for consumption and also good water for irrigation purpose with low sodium and alkalinity ratio respectively. Government water projects are recommended in the area for sustainable domestic and agricultural water supply to ease the stress of water supply problems.Keywords: groundwater, hydrochemical, physichochemical, water-type, sodium adsorption ratio
Procedia PDF Downloads 1263644 Extracting Polyhydroxyalkanoates from Waste Sludge of Husbandry Industry Wastewater Treatment Plants
Authors: M. S. Lu, Y. P. Tsai, H. Shu, K. F. Chen, L. L. Lai
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This study used sodium hypochlorite/sodium dodecyl sulfate method to successfully extract polyhydroxyalkanoates (PHA) from the wasted sludge of a husbandry industry wastewater treatment plant. We investigated the optimum operational conditions of three key factors with respect to effectively extract PHAs from husbandry industry wastewater sludge, including the sodium hypochlorite concentration, liquid-solid ratio, and reaction time. The experimental results showed the optimum operational conditions for polyhydroxyalkanoate recovery as follows: (1) being digested by the sodium hypochlorite/sodium dodecyl sulfate solution with 15% (v/v) of hypochlorite concentration, (2) being operated at the condition of 1.25 mLmg-1 of liquid-solid ratio, and (3) being reacted for more than 60 min. Under these conditions, the content of the recovered PHAs was about 53.2±0.66 mgPHAs/gVSS, and the purity of the recovered PHAs was about 78.5±6.91 wt%. The recovered PHAs were further used to produce biodegradable plastics for decomposition test buried in soils. The decomposition test showed 66.5% of the biodegradable plastics produced in the study remained after being buried in soils for 49 days. The cost for extracting PHAs is about 10.3 US$/kgPHAs and is lower than those produced by pure culture methods (12-15 US$/kgPHAs).Keywords: biodegradable plastic, biopolymers, polyhydroxyalkanoates (PHAs), waste sludge
Procedia PDF Downloads 3353643 A Prospective Study on Alkali Activated Bottom Ash-GGBS Blend in Paver Blocks
Authors: V. Revathi, J. Thaarrini, M. Venkob Rao
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This paper presents a study on use of alkali activated bottom ash (BA) and ground granulated blast furnace slag (GGBS) blend in paver blocks. A preliminary effort on alkali-activated bottom ash, blast furnace slag based geopolymer (BA-GGBS-GP) mortar with river sand was carried out to identify the suitable mix for paver block. Several mixes were proposed based on the combination of BA-GGBS. The percentage ratio of BA:GGBS was selected as 100:0, 75:25, 50:50, 25:75 and 0:100 for the source material. Sodium based alkaline activators were used for activation. The molarity of NaOH was considered as 8M. The molar ratio of SiO2 to Na2O was varied from 1 to 4. Two curing mode such as ambient and steam curing 60°C for 24 hours were selected. The properties of paver block such as compressive strength split tensile strength, flexural strength and water absorption were evaluated as per IS15658:2006. Based on the preliminary study on BA-GGBS-GP mortar, the combinations of 25% BA with 75% GGBS mix for M30 and 75% BA with 25% GGBS mix for M35 grade were identified for paver block. Test results shows that the combination of BA-GGBS geopolymer paver blocks attained remarkable compressive strength under steam curing as well as in ambient mode at 3 days. It is noteworthy to know BA-GGBS-GP has promising future in the construction industry.Keywords: bottom ash, GGBS, alkali activation, paver block
Procedia PDF Downloads 3483642 Effect of Birks Constant and Defocusing Parameter on Triple-to-Double Coincidence Ratio Parameter in Monte Carlo Simulation-GEANT4
Authors: Farmesk Abubaker, Francesco Tortorici, Marco Capogni, Concetta Sutera, Vincenzo Bellini
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This project concerns with the detection efficiency of the portable triple-to-double coincidence ratio (TDCR) at the National Institute of Metrology of Ionizing Radiation (INMRI-ENEA) which allows direct activity measurement and radionuclide standardization for pure-beta emitter or pure electron capture radionuclides. The dependency of the simulated detection efficiency of the TDCR, by using Monte Carlo simulation Geant4 code, on the Birks factor (kB) and defocusing parameter has been examined especially for low energy beta-emitter radionuclides such as 3H and 14C, for which this dependency is relevant. The results achieved in this analysis can be used for selecting the best kB factor and the defocusing parameter for computing theoretical TDCR parameter value. The theoretical results were compared with the available ones, measured by the ENEA TDCR portable detector, for some pure-beta emitter radionuclides. This analysis allowed to improve the knowledge of the characteristics of the ENEA TDCR detector that can be used as a traveling instrument for in-situ measurements with particular benefits in many applications in the field of nuclear medicine and in the nuclear energy industry.Keywords: Birks constant, defocusing parameter, GEANT4 code, TDCR parameter
Procedia PDF Downloads 1403641 Implementation of Maqasid Sharia in Islamic Financial Institution in Indonesia
Authors: Deden Misbahudin Muayyad, Lavlimatria Esya
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Up to the month of June 2015, Indonesia has 12 Islamic Commercial Banks, 22 Islamic Business Unit, 327 offices in 33 provinces. The initial purpose of the establishment of Islamic financial institutions is to achieve and the welfare of the people in this world and in the hereafter. To realize these goals, the Islamic financial institutions in every kind of aspect of product development and in terms of operations should be based on maqashid sharia, namely keeping the faith, keep the soul, keep the sense, maintain the property, keeping the offspring. To see whether Islamic banking grounded in maqasid sharia, the Islamic banking performance measurements based on the principles of maqasid sharia. Banking performance measurement is not only focusing on profit and other financial measures, but put other values of banks reflects the size of the benefit of non-profit in accordance with the bank's objectives. The measurement using the measurement of financial performance called maqasid sharia index. Maqasid syariah index is a model of Islamic banking performance measurement in accordance with the objectives and characteristics of Islamic banking. Maqasid syariah index was developed based on three main factors, namely the education of individuals, the creation of justice, the achievement of well-being, where the three factors were in accordance with the common goal of maqasid sharia is achieving prosperity and avoid evil. Maqasid syariah index shows that maqasid sharia approach can be a strategic alternative approach to describe how good the performance of the banking system and it can be implemented in the comprehensive policy strategy. This study uses a model of performance measurement framework based on maqasid syariah, in addition to financial performance measures that already exist. Methods to develop the idea of a performance measurement framework of Islamic banking by maqasid sharia is the Sekaran method. Operationally, the methods have now able to describe the elements that will be measured by this study. This is done by observing the behavior of the dimensions illustrated through a concept that has been set. These dimensions translate into derivative elements that can be observed and more scalable, so it can establish measurement indices. This research is descriptive quantitative. Techniques are being made to collect data in this paper is by using purposive sampling method, with 12 Islamic Commercial Banks that qualify as research samples. The financial data taken at 12 banks was sourced from the annual financial statements the period 2008 to 2012 with consideration of the database and ease of access to data. The ratio measured in this study only 7 ratio used in determining the performance of Islamic banking, namely: four ratio refers to the sharia objectives related to education. three ratio while again referring to sharia objectives related to the achievement of welfare. While other ratios associated with justice can not be used in this study because of the limited data used. Total overall calculation of performance indicators and performance ratios on each goal for each bank describes the maqasid syariah index.Keywords: Islamic banking, Maslahah, maqashid syariah, maqashid syariah index
Procedia PDF Downloads 2603640 Oscillatory Electroosmotic Flow of Power-Law Fluids in a Microchannel
Authors: Rubén Bãnos, José Arcos, Oscar Bautista, Federico Méndez
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The Oscillatory electroosmotic flow (OEOF) in power law fluids through a microchannel is studied numerically. A time-dependent external electric field (AC) is suddenly imposed at the ends of the microchannel which induces the fluid motion. The continuity and momentum equations in the x and y direction for the flow field were simplified in the limit of the lubrication approximation theory (LAT), and then solved using a numerical scheme. The solution of the electric potential is based on the Debye-H¨uckel approximation which suggest that the surface potential is small,say, smaller than 0.025V and for a symmetric (z : z) electrolyte. Our results suggest that the velocity profiles across the channel-width are controlled by the following dimensionless parameters: the angular Reynolds number, Reω, the electrokinetic parameter, ¯κ, defined as the ratio of the characteristic length scale to the Debye length, the parameter λ which represents the ratio of the Helmholtz-Smoluchowski velocity to the characteristic length scale and the flow behavior index, n. Also, the results reveal that the velocity profiles become more and more non-uniform across the channel-width as the Reω and ¯κ are increased, so oscillatory OEOF can be really useful in micro-fluidic devices such as micro-mixers.Keywords: low zeta potentials, non-newtonian, oscillatory electroosmotic flow, power-law model
Procedia PDF Downloads 1633639 Improving the Growth Performance of Beetal Goat Kids Weaned at Various Stages with Various Levels of Dietary Protein in Starter Ration under High Input Feeding System
Authors: Ishaq Kashif, Muhammad Younas, Muhammad Riaz, Mubarak Ali
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Poor feeding management during pre-weaning period is one of the factors resulting in compromised growth of Beetal kids fattened for meat purpose. The main reason for this anomaly may be less milk offered to kids and non-serious efforts for its management. This study was planned to find the most appropriate protein level suiting the age of the weaning while shifting animals to high input feeding system. Total of 42 Beetal male kids having 30 (±10), 60 (±10) and 90 (±10) days of age were selected with 16 in each age group. They were designated as G30, G60 and G90, respectively. The weights of animals were; 8±2 kg (G30), 12±2 kg (G60) and 16±2 kg (G90), respectively. All animals were weaned by introducing the total mix feed gradually and withdrawing the milk during the adjustment period of two weeks. The pelleted starter ration (total mix feed) with three various dietary protein levels designated as R1 (16% CP), R2 (20% CP) and R3 (26% CP) were introduced. The control group was reared on the fodder (Maize). The starter rations were iso-caloric and were offered for six-week duration. All animals were exposed to treatment using two-factor factorial (3×3) plus control treatment arrangement under completely randomized design. The data were collected on average daily feed intake (ADFI), average daily gain (ADG), gain to intake ratio, Klieber ratio (KR), body measurements and blood metabolites of kids. The data was analyzed using aov function of R-software. The statistical analysis showed that starter feed protein levels and age of weaning had significant interaction for ADG (P < 0.001), KR (P < 0.001), ADFI (P < 0.05) and blood urea nitrogen (P < 0.05) while serum creatinine and feed conversion had non-significant interaction. The trend analysis revealed that ADG had significant quadratic interaction (P < 0.05) within protein levels and age of weaning. It was found that animals weaned at 30 or 60 days, on R2 diet had better ADG (46.8 gm/day and 87.06 gm/day, respectively) weaned at 60 days of age. The animals weaned at 90 days had best ADG (127 gm/day) with R1. It is concluded that animal weaned at 30 or 40 days required 20% CP for better growth performance while animal at 90 days showed better performance with 16% CP.Keywords: average daily gain, starter protein levels, weaning age, gain to intake ratio
Procedia PDF Downloads 2403638 Direct Oxidation Synthesis for a Dual-Layer Silver/Silver Orthophosphate with Controllable Tetrahedral Structure as an Active Photoanode for Solar-Driven Photoelectrochemical Water Splitting
Authors: Wen Cai Ng, Saman Ilankoon, Meng Nan Chong
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The vast increase in global energy demand, coupled with the growing concerns on environmental issues, has triggered the search for cleaner alternative energy sources. In view of this, the photoelectrochemical (PEC) water splitting offers a sustainable hydrogen (H2) production route that only requires solar energy, water, and PEC system operating in an ambient environment. However, the current advancement of PEC water splitting technologies is still far from the commercialization benchmark indicated by the solar-to-H2 (STH) efficiency of at least 10 %. This is largely due to the shortcomings of photoelectrodes used in the PEC system, such as the rapid recombination of photogenerated charge carriers and limited photo-responsiveness in the visible-light spectrum. Silver orthophosphate (Ag3PO4) possesses many desirable intrinsic properties for the fabrication into photoanode used in PEC systems, such as narrow bandgap of 2.4 eV and low valence band (VB) position. Hence, in this study, a highly efficient Ag3PO4-based photoanode was synthesized and characterized. The surface of the Ag foil substrate was directly oxidized to fabricate a top layer composed of {111}-bound Ag3PO4 tetrahedrons layer with a porous structure, forming the dual-layer Ag/Ag3PO4 photoanode. Furthermore, the key synthesis parameters were systematically investigated by varying the concentration ratio of capping agent-to-precursor (R), the volume ratio of hydrogen peroxide (H2O2)-to-water, and reaction period. Results showed that the optimized dual-layer Ag/Ag3PO4 photoanode achieved a photocurrent density as high as 4.19 mA/cm2 at 1 V vs. Ag/AgCl for the R-value of 4, the volume ratio of H2O2-to-water of 3:5 and 20 h reaction period. The current work provides a solid foundation for further nanoarchitecture modification strategies on Ag3PO4-based photoanodes for more efficient PEC water splitting applications. This piece of information needs to be backed up by evidence; therefore, you need to provide a reference. As the abstract should be self-contained, all information requiring a reference should be removed. This is a fact known to the area of research, and not necessarily required a reference to support.Keywords: solar-to-hydrogen fuel, photoelectrochemical water splitting, photoelectrode, silver orthophosphate
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