Search results for: inverse models of data envelopment analysis
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 44801

Search results for: inverse models of data envelopment analysis

12941 Rapid Atmospheric Pressure Photoionization-Mass Spectrometry (APPI-MS) Method for the Detection of Polychlorinated Dibenzo-P-Dioxins and Dibenzofurans in Real Environmental Samples Collected within the Vicinity of Industrial Incinerators

Authors: M. Amo, A. Alvaro, A. Astudillo, R. Mc Culloch, J. C. del Castillo, M. Gómez, J. M. Martín

Abstract:

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) of course comprise a range of highly toxic compounds that may exist as particulates within the air or accumulate within water supplies, soil, or vegetation. They may be created either ubiquitously or naturally within the environment as a product of forest fires or volcanic eruptions. It is only since the industrial revolution, however, that it has become necessary to closely monitor their generation as a byproduct of manufacturing/combustion processes, in an effort to mitigate widespread contamination events. Of course, the environmental concentrations of these toxins are expected to be extremely low, therefore highly sensitive and accurate methods are required for their determination. Since ionization of non-polar compounds through electrospray and APCI is difficult and inefficient, we evaluate the performance of a novel low-flow Atmospheric Pressure Photoionization (APPI) source for the trace detection of various dioxins and furans using rapid Mass Spectrometry workflows. Air, soil and biota (vegetable matter) samples were collected monthly during one year from various locations within the vicinity of an industrial incinerator in Spain. Analytes were extracted and concentrated using soxhlet extraction in toluene and concentrated by rotavapor and nitrogen flow. Various ionization methods as electrospray (ES) and atmospheric pressure chemical ionization (APCI) were evaluated, however, only the low-flow APPI source was capable of providing the necessary performance, in terms of sensitivity, required for detecting all targeted analytes. In total, 10 analytes including 2,3,7,8-tetrachlorodibenzodioxin (TCDD) were detected and characterized using the APPI-MS method. Both PCDDs and PCFDs were detected most efficiently in negative ionization mode. The most abundant ion always corresponded to the loss of a chlorine and addition of an oxygen, yielding [M-Cl+O]- ions. MRM methods were created in order to provide selectivity for each analyte. No chromatographic separation was employed; however, matrix effects were determined to have a negligible impact on analyte signals. Triple Quadrupole Mass Spectrometry was chosen because of its unique potential for high sensitivity and selectivity. The mass spectrometer used was a Sciex´s Qtrap3200 working in negative Multi Reacting Monitoring Mode (MRM). Typically mass detection limits were determined to be near the 1-pg level. The APPI-MS2 technology applied to the detection of PCDD/Fs allows fast and reliable atmospheric analysis, minimizing considerably operational times and costs, with respect other technologies available. In addition, the limit of detection can be easily improved using a more sensitive mass spectrometer since the background in the analysis channel is very low. The APPI developed by SEADM allows polar and non-polar compounds ionization with high efficiency and repeatability.

Keywords: atmospheric pressure photoionization-mass spectrometry (APPI-MS), dioxin, furan, incinerator

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12940 Factors Motivating Experienced Secondary Teachers to Remain in the Teaching Profession

Authors: Joselito Castro Gutierrez, Herbert Orteza, Jervie Boligon, Kenneth Esteves, Edrick Kevin Ferrer, Mark Kevin Torres, Patrick Vergara

Abstract:

Teaching is a noble profession that involves an effective imparting of holistic learning. Consequently, it requires a driving force called motivation. This research aims to determine the motivating factors, problems encountered, solutions made by experienced secondary school teachers to remain in the teaching profession. A mixed unstructured/structured questionnaire was used for gathering data among public secondary school teachers. The researchers have arrived to a conclusion that the dominant motivating factors of teachers to stay in the profession are altruism, extrinsic factors, and self-efficacy. Meanwhile, the prevalent problems these experienced secondary teachers experienced are mutual dilemma, work overload, and personal issues. Teachers have varied methods on solving the problem which are: a) Direct Solution; b) Indirect Solution; and c) Pseudo-Solutions. Lastly, the factors, problems, and solutions, have influential effects on how long a teacher would sustain in teaching which would manifest as positive, negative and neutral effects.

Keywords: motivation, common problems of teachers, strategies in solving problems, teaching profession

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12939 Numerical Simulations of Electronic Cooling with In-Line and Staggered Pin Fin Heat Sinks

Authors: Yue-Tzu Yang, Hsiang-Wen Tang, Jian-Zhang Yin, Chao-Han Wu

Abstract:

Three-dimensional incompressible turbulent fluid flow and heat transfer of pin fin heat sinks using air as a cooling fluid are numerically studied in this study. Two different kinds of pin fins are compared in the thermal performance, including circular and square cross sections, both are in-line and staggered arrangements. The turbulent governing equations are solved using a control-volume- based finite-difference method. Subsequently, numerical computations are performed with the realizable k - ԑ turbulence for the parameters studied, the fin height H, fin diameter D, and Reynolds number (Re) in the range of 7 ≤ H ≤ 10, 0.75 ≤ D ≤ 2, 2000 ≤ Re ≤ 126000 respectively. The numerical results are validated with available experimental data in the literature and good agreement has been found. It indicates that circular pin fins are streamlined in comparing with the square pin fins, the pressure drop is small than that of square pin fins, and heat transfer is not as good as the square pin fins. The thermal performance of the staggered pin fins is better than that of in-line pin fins because the staggered arrangements produce large disturbance. Both in-line and staggered arrangements show the same behavior for thermal resistance, pressure drop, and the entropy generation.

Keywords: pin-fin, heat sinks, simulations, turbulent flow

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12938 Numerical Modeling of Artisanal and Small Scale Mining of Coltan in the African Great Lakes Region

Authors: Sergio Perez Rodriguez

Abstract:

Coltan Artisanal and Small-Scale Mining (ASM) production from Africa's Great Lakes region has previously been addressed at large scales, notably from regional to country levels. The current findings address the unresolved issue of a production model of ASM of coltan ore by an average Democratic Republic of Congo (DRC) mineworker, which can be used as a reference for a similar characterization of the daily labor of counterparts from other countries in the region. To that end, the Fundamental Equation of Mineral Production has been applied, considering a miner's average daily output of coltan, estimated in the base of gross statistical data gathered from reputable sources. Results indicate daily yields of individual miners in the order of 300 g of coltan ore, with hourly peaks of production in the range of 30 to 40 g of the mineral. Yields are expected to be in the order of 5 g or less during the least productive hours. These outputs are expected to be achieved during the halves of the eight to ten hours of daily working sessions that these artisanal laborers can attend during the mining season.

Keywords: coltan, mineral production, production to reserve ratio, artisanal mining, small-scale mining, ASM, human work, Great Lakes region, Democratic Republic of Congo

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12937 Factors Influencing International Second Language Student's Perceptions of Academic Writing Practices

Authors: A. Shannaq

Abstract:

English is the accepted lingua franca of the academic world, and English medium higher education institutions host many second-language speakers of English (L2) who wish to pursue their studies through the medium of English. Assessment in higher education institutions is largely done in writing, which makes the mastery of academic writing essential. While such mastery can be, and often is, difficult for students who speak English as a first language, it is undoubtedly more so for L2 students attempting to adopt Anglophone academic written norms. There does not appear to be a great deal of research with regard to L2 students’ perceptions of their academic writing practices. This research investigates the writing practices of international L2 students in their first year of undergraduate study at NZ universities. Qualitative longitudinal data in the form of semi-structured interviews and documentation (assignments’ written instructions, students’ written assignments, tutors’ feedback on the students’ assignments) were collected from 4 undergraduate international L2 students at the beginning, middle, and end of the academic year 2017. Findings reveal that motivation, agency, and self-efficacy impact students’ perceptions of their academic writing practices and define the course of actions learners take under the time constraints which are set for their assignments.

Keywords: academic writing, English as a second language, international second language students, undergraduate writing practices

Procedia PDF Downloads 139
12936 Green Supply Chain Design: A Mathematical Modeling Approach

Authors: Nusrat T. Chowdhury

Abstract:

Green Supply Chain Management (GSCM) is becoming a key to success for profitable businesses. The various activities contributing to carbon emissions in a supply chain are transportation, ordering and holding of inventory. This research work develops a mixed-integer nonlinear programming (MINLP) model that considers the scenario of a supply chain with multiple periods, multiple products and multiple suppliers. The model assumes that the demand is deterministic, the buyer has a limited storage space in each period, the buyer is responsible for the transportation cost, a supplier-dependent ordering cost applies for each period in which an order is placed on a supplier and inventory shortage is permissible. The model provides an optimal decision regarding what products to order, in what quantities, with which suppliers, and in which periods in order to maximize the profit. For the purpose of evaluating the carbon emissions, three different carbon regulating policies i.e., carbon cap-and-trade, the strict cap on carbon emission and carbon tax on emissions, have been considered. The proposed MINLP has been validated using a randomly generated data set.

Keywords: green supply chain, carbon emission, mixed integer non-linear program, inventory shortage, carbon cap-and-trade

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12935 Impact of Machining Parameters on the Surface Roughness of Machined PU Block

Authors: Louis Denis Kevin Catherine, Raja Aziz Raja Ma’arof, Azrina Arshad, Sangeeth Suresh

Abstract:

Machining parameters are very important in determining the surface quality of any material. In the past decade, some new engineering materials were developed for the manufacturing industry which created a need to conduct an investigation on the impact of the said parameters on their surface roughness. The polyurethane (PU) block is widely used in the automotive industry to manufacture parts such as checking fixtures that are used to verify the dimensional accuracy of automotive parts. In this paper, the design of experiment (DOE) was used to investigate the effect of the milling parameters on the PU block. Furthermore, an analysis of the machined surface chemical composition was done using scanning electron microscope (SEM). It was found that the surface roughness of the PU block is severely affected when PU undergoes a flood machining process instead of a dry condition. In addition, the step over and the silicon content were found to be the most significant parameters that influence the surface quality of the PU block.

Keywords: polyurethane (PU), design of experiment (DOE), scanning electron microscope (SEM), surface roughness

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12934 Knowledge Management as Tool for Environmental Management System Implementation in Higher Education Institutions

Authors: Natalia Marulanda Grisales

Abstract:

The most significant changes in the characteristics of consumers have contributed to the development and adoption of methodologies and tools that enable organizations to be more competitive in the marketplace. One of these methodologies is the integration of Knowledge Management (KM) phases and Environmental Management Systems (EMS). This integration allows companies to manage and share the required knowledge for EMS adoption, from the place where it is generated to the place where it is going to be exploited. The aim of this paper is to identify the relationship between KM phases as a tool for the adoption of EMS in HEI. The methodology has a descriptive scope and a qualitative approach. It is based on a case study and a review of the literature about KM and EMS. We conducted 266 surveys to students, professors and staff at Minuto de Dios University (Colombia). Data derived from the study indicate that if a HEI wants to achieve an adequate knowledge acquisition and knowledge transfer, it must have clear goals for implementing an EMS. Also, HEI should create empowerment and training spaces for students, professors and staff. In the case study, HEI must generate alternatives that enhance spaces of knowledge appropriation. It was found that 85% of respondents have not received any training from HEI about EMS. 88% of respondents believe that the actions taken by the university are not efficient to knowledge transfer in order to develop an EMS.

Keywords: environmental management systems, higher education institutions, knowledge management, training

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12933 Hybrid Subspace Approach for Time Delay Estimation in MIMO Systems

Authors: Mojtaba Saeedinezhad, Sarah Yousefi

Abstract:

In this paper, we present a hybrid subspace approach for Time Delay Estimation (TDE) in multivariable systems. While several methods have been proposed for time delay estimation in SISO systems, delay estimation in MIMO systems were always a big challenge. In these systems the existing TDE methods have significant limitations because most of procedures are just based on system response estimation or correlation analysis. We introduce a new hybrid method for TDE in MIMO systems based on subspace identification and explicit output error method; and compare its performance with previously introduced procedures in presence of different noise levels and in a statistical manner. Then the best method is selected with multi objective decision making technique. It is shown that the performance of new approach is much better than the existing methods, even in low signal-to-noise conditions.

Keywords: system identification, time delay estimation, ARX, OE, merit ratio, multi variable decision making

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12932 Investigation of Suicide by Poison as a Result of Domestic Violence

Authors: Nazih Ramadan, Ghada Hassabo

Abstract:

Background and Aims: Domestic violence and other forms of violence against women and other family members are known to be substantial and widespread, with women more likely than men to be abused mostly by their partner, which is known as gender-based violence. Domestic violence is a major precipitating factor for suicide in many communities especially in our Middle East area. The aim of the study is to show the real relation between suicidal attempts and domestic violence especially in female victims. We tried also through this study to know the most common age at which the abused person attempt suicide, the perpetrator, the educational level of the abused person, and the social level of them. Materials and Methods: In this study, we collect data from 150 victims of suicidal attempts who came to seek medical help at National Poisoning Center. They were asked to answer a preformed questionnaire after giving consent. Results: The study shows that women are at higher risk for suicidal behavior and that suicidal attempt is directly proportionate to low level of education and low social class situation. Conclusion: the study shows the strong relation between attempting suicide and exposure to domestic violence. At the end of this work, we recommend understanding the broad scope and tragic impact of domestic violence; further research is needed concerning domestic violence-related suicide.

Keywords: Cairo, domestic violence, domestic violence-related suicide, violence against women

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12931 Development, Characterization and Properties of Novel Quaternary Rubber Nanocomposites

Authors: Kumar Sankaran, Santanu Chattopadhyay, Golok Behari Nando, Sujith Nair, Sreejesh Arayambath, Unnikrishnan Govindan

Abstract:

Rubber nanocomposites based on Bromobutyl rubber (BIIR), Polyepichlorohydrin rubber (CO), Carbon black (CB) and organically modified montmorillonite clay (NC) were prepared via melt compounding technique. The developed quaternary nanocomposites were characterized analytically and their properties were compared against the standard BIIR compound. BIIR-CO nanocomposites showed improved physico-mechanical properties as compared to that of the standard BIIR compound. Hybrid microstructure (NC-CB) development, clay exfoliation and better filler dispersion in the quaternary nanocomposite significantly contributed to the overall enhancement of properties. Introduction of CO in the system increased the specific gravity and hardness of the compound as compared to that of the standard compound. XRD analysis, AFM imaging and HR-TEM measurements confirmed exfoliation and a good level of dispersion of the NC in the composites. Permeability of developed BIIR-CO nanocomposites decreases significantly as compared to that of the standard BIIR compound.

Keywords: rubber nanocomposites, morphology, permeability, BIIR

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12930 Improved Pitch Detection Using Fourier Approximation Method

Authors: Balachandra Kumaraswamy, P. G. Poonacha

Abstract:

Automatic Music Information Retrieval has been one of the challenging topics of research for a few decades now with several interesting approaches reported in the literature. In this paper we have developed a pitch extraction method based on a finite Fourier series approximation to the given window of samples. We then estimate pitch as the fundamental period of the finite Fourier series approximation to the given window of samples. This method uses analysis of the strength of harmonics present in the signal to reduce octave as well as harmonic errors. The performance of our method is compared with three best known methods for pitch extraction, namely, Yin, Windowed Special Normalization of the Auto-Correlation Function and Harmonic Product Spectrum methods of pitch extraction. Our study with artificially created signals as well as music files show that Fourier Approximation method gives much better estimate of pitch with less octave and harmonic errors.

Keywords: pitch, fourier series, yin, normalization of the auto- correlation function, harmonic product, mean square error

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12929 Compensatory Increased Activities of Mitochondrial Respiratory Chain Complexes from Eyes of Glucose-Immersed Zebrafish

Authors: Jisun Jun, Eun Ko, Sooim Shin, Kitae Kim, Moonsung Choi

Abstract:

Diabetes is a metabolic disease characterized by hyperglycemia, insulin resistant, mitochondrial dysfunction. Diabetes is associated with the development of diabetic retinopathy resulting in worsening vision and eventual blindness. In this study, eyes were enucleated from glucose-immersed zebrafish which is a good animal model to generate diabetes, and then mitochondria were isolated to evaluate activities of mitochondrial electron transfer complexes. Surprisingly, the amount of isolated mitochondria was increased in eyes from glucose-immersed zebrafish compared to those from non-glucose-immerged zebrafish. Spectrophotometric analysis for measuring activities of mitochondrial complex I, II, III, and IV revealed that mitochondria functions was even enhanced in eyes from glucose-immersed zebrafish. These results indicated that 3 days or 7 days glucose-immersion on zebrafish to induce diabetes might contribute metabolic compensatory mechanism to restore their mitochondrial homeostasis on the early stage of diabetes in eyes.

Keywords: diabetes, glucose immersion, mitochondrial complexes, zebrafish

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12928 Chemical and Mechanical Characterization of Composites Reinforced with Coconut Fiber in the Polymeric Matrix of Recycled PVC

Authors: Luiz C. G. Pennafort Jr., Alexandre de S. Rios, Enio P. de Deus

Abstract:

In the search for materials that replace conventional polymers in order to preserve natural resources, combined with the need to minimize the problems arising from environmental pollution generated by plastic waste, comes the recycled materials biodegradable, especially the composites reinforced with natural fibers. However, such materials exhibit properties little known, requiring studies of manufacturing methods and characterization of these composites. This article shows informations about preparation and characterization of a composite produced by extrusion, which consists of recycled PVC derived from the recycling of materials discarded, added of the micronized coconut fiber. The recycled PVC with 5% of micronized fiber were characterized by X-ray diffraction, thermogravimetric, differential scanning calorimetry, mechanical analysis and optical microscopy. The use of fiber in the composite caused a decrease in its specific weight, due to the lower specific weight of fibers and the appearance of porosity, in addition to the decrease of mechanical properties.

Keywords: recycled PVC, coconut fiber, characterization, composites

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12927 The Effect of Chelate to RE Ratio on Upconversion Emissions Property of NaYF4: Yb3+ and Tm3+ Nanocrystals

Authors: M. Kaviani Darani, S. Bastani, M. Ghahari, P. Kardar

Abstract:

In this paper the NaYF4: Yb3+, Tm3+ nanocrystals were synthesized by hydrothermal method. Different chelating ligand type (citric acid, butanoic acid, and AOT) was selected to investigate the effect of their concentration on upconversion efficiency. Crystal structure and morphology have been well characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis. Photo luminescence were recorded on a spectrophotometer equipped with 980 nm laser diode az excitation source and an integerating sphere. The products with various morphologies range from sphere to cubic, hexagonal,prism and nanorods were prepared at different ratios. The particle size was found to be dependent on the nucleation rate, which, in turn, was affected by type and concentration of ligands. The optimum amount of chelate to RE ratio was obtained 0.75, 1.5, and 1 for Citric Acid, Butanoic Acid and AOT, respectively. Emissions in the UV (1D2-3H6), blue-violet(1D2-3F4), blue (1G4-3H6), red (1G4-3F4), and NIR (1G4-3H5) were observed and were the direct result of subsequent transfers of energy from the Yb3+ ion to the Tm3+ ion.

Keywords: upconversion nanoparticles, NaYF4, lanthanide, hydrothermal

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12926 Bacillus licheniformis sp. nov. PS-6, an Arsenic Tolerance Bacterium with Biotransforming Potential Isolated from Sediments of Pichavaram Mangroves of South India

Authors: Padmanabhan D, Kavitha S

Abstract:

The purpose of the study is to investigate arsenic resistance ability of indigenous microflora and its ability to utilize arsenic species form containing water source. PS-6 potential arsenic tolerance bacterium was screened from thirty isolates from Pichavaram Mangroves of India having tolerance to grow up to 1000 mg/l of As (V) and 800 mg/l of As (III) and arsenic utilization ability of 98 % of As (V) and 97% of As (III) with initial concentration of 3-5 mg/l within 48 hrs. Optimum pH and temperature was found to be ~7-7.4 and 37°C. Active growth of PS-6 in minimal salt media (MSB) helps in cost effective biomass production. Dry weight analysis of PS-6 has shown significant difference in biomass when exposed to As (III) and As (V). Protein level study of PS-6 after exposing to As (V) and As (III) shown modification in total protein concentration and variation in SDS-PAGE pattern. PS-6 was identified as Bacillus licheniformis based on partially sequenced of 16S rRNA using NCBI Blast. Further investigation will help in using this potential bacterium as a well-grounded source for urgency.

Keywords: arsenite, arsenate, Bacillus licheniformis, utilization

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12925 Barriers to Tuberculosis Detection in Portuguese Prisons

Authors: M. F. Abreu, A. I. Aguiar, R. Gaio, R. Duarte

Abstract:

Background: Prison establishments constitute high-risk environments for the transmission and spread of tuberculosis (TB), given their epidemiological context and the difficulty of implementing preventive and control measures. Guidelines for control and prevention of tuberculosis in prisons have been described as incomplete and heterogeneous internationally, due to several identified obstacles, for example scarcity of human resources and funding of prisoner health services. In Portugal, a protocol was created in 2014 with the aim to define and standardize procedures of detection and prevention of tuberculosis within prisons. Objective: The main objective of this study was to identify and describe barriers to tuberculosis detection in prisons of Porto and Lisbon districts in Portugal. Methods: A cross-sectional study was conducted from 2ⁿᵈ January 2018 till 30ᵗʰ June 2018. Semi-structured questionnaires were applied to health care professionals working in the prisons of the districts of Porto (n=6) and Lisbon (n=8). As inclusion criteria we considered having work experience in the area of tuberculosis (either in diagnosis, treatment, or follow up). The questionnaires were self-administered, in paper format. Descriptive analyses of the questionnaire variables were made using frequencies and median. Afterwards, a hierarchical agglomerative clusters analysis was performed. After obtaining the clusters, the chi-square test was applied to study the association between the variables collected and the clusters. The level of significance considered was 0.05. Results: From the total of 186 health professionals, 139 met the criteria of inclusion and 82 health professionals were interviewed (62,2% of participation). Most were female, nurses, with a median age of 34 years, with term employment contract. From the cluster analysis, two groups were identified with different characteristics and behaviors for the procedures of this protocol. Statistically significant results were found in: elements of cluster 1 (78% of the total participants) work in prisons for a longer time (p=0.003), 45,3% work > 4 years while 50% of the elements of cluster 2 work for less than a year, and more frequently answered they know and apply the procedures of the protocol (p=0.000). Both clusters answered frequently the need of having theoretical-practical training for TB (p=0.000), especially in the areas of diagnosis, treatment and prevention and that there is scarcity of funding to prisoner health services (p=0.000). Regarding procedures for TB screening (periodic and contact screening) and procedures for transferring a prisoner with this disease, cluster 1 also answered more frequently to perform them (p=0.000). They also referred that the material/equipment for TB screening is accessible and available (p=0.000). From this clusters we identified as barriers scarcity of human resources, the need to theoretical-practical training for tuberculosis, inexperience in working in health services prisons and limited knowledge of protocol procedures. Conclusions: The barriers found in this study are the same described internationally. This protocol is mostly being applied in portuguese prisons. The study also showed the need to invest in human and material resources. This investigation bridged gaps in knowledge that could help prison health services optimize the care provided for early detection and adherence of prisoners to treatment of tuberculosis.

Keywords: barriers, health care professionals, prisons, protocol, tuberculosis

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12924 Numerical and Experimental Investigation of the Aerodynamic Performances of Counter-Rotating Rotors

Authors: Ibrahim Beldjilali, Adel Ghenaiet

Abstract:

The contra-rotating axial machine is a promising solution for several applications, where high pressure and efficiencies are needed. Also, they allow reducing the speed of rotation, the radial spacing and a better flexibility of use. However, this requires a better understanding of their operation, including the influence of second rotor on the overall aerodynamic performances. This work consisted of both experimental and numerical studies to characterize this counter-rotating fan, especially the analysis of the effects of the blades stagger angle and the inter-distance between the rotors. The experimental study served to validate the computational fluid dynamics model (CFD) used in the simulations. The numerical study permitted to cover a wider range of parameter and deeper investigation on flow structures details, including the effects of blade stagger angle and inter-distance, associated with the interaction between the rotors. As a result, there is a clear improvement in aerodynamic performance compared with a conventional machine.

Keywords: aerodynamic performance, axial fan, counter rotating rotors, CFD, experimental study

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12923 Estimation of Seismic Deformation Demands of Tall Buildings with Symmetric Setbacks

Authors: Amir Alirezaei, Shahram Vahdani

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This study estimates the seismic demands of tall buildings with central symmetric setbacks by using nonlinear time history analysis. Three setback structures, all 60-story high with setback in three levels, are used for evaluation. The effects of irregularities occurred by setback, are evaluated by determination of global-drift, story-displacement and story drift. Story-displacement is modified by roof displacement and first story displacement and story drift is modified by global drift. All results are calculated at the center of mass and in x and y direction. Also the absolute values of these quantities are determined. The results show that increasing of vertical irregularities increases the global drift of the structure and enlarges the deformations in the height of the structure. It is also observed that the effects of geometry irregularity in the seismic deformations of setback structures are higher than those of mass irregularity.

Keywords: deformation demand, drift, setback, tall building

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12922 Physico-Chemical and Sensory Properties of Orange Marmalade Supplemented with Aloe vera Powder

Authors: Farhat Rashid

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A study was conducted at the Institute of Food Science and Nutrition, University of Sargodha, Sargodha, Pakistan, to evaluate the effect of different concentration of Aloe vera (Aloe barbadensis Mill.) powder on physicochemical and sensory properties of orange marmalade. All treatments (0, 2, 4 6, 8 and 10% Aloe vera powder) were analyzed for titratable acidity, TSS, pH, moisture, fat, fiber and protein contents. The data indicated gradual increase in titratable acidity (0.08 to 0.18%), moisture (0.23 to 0.48%), protein (0.09 to 0.40%) and fiber (0.12 to 1.03%) among all treatments with increasing concentration of Aloe vera powder. However, a decreasing trend in pH (3.81 to 2.74), TSS (68 to 56 °Brix) and fat content (1.1 to 0.08%) was noticed with gradual increase in concentration of Aloe vera powder in orange marmalade. Sensory attributes like color, taste, texture, flavor and overall acceptability were found acceptable among all treatments but T1 (2% Aloe vera powder) was liked most and T5 (10% Aloe vera powder) was least appealing to the judges. It is concluded from present study that the addition of different concentrations of Aloe vera powder in orange marmalade significantly affected the physicochemical and sensory properties of marmalade.

Keywords: orange marmalade, Aloe vera, Aloe barbadensis mill, physicochemical, characteristics, organoleptic properties, Pakistan, treatments, significance

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12921 Approximation of Selenium Content in Watermelons for Use as a Food Supplement

Authors: Roggers Mutwiri Aron

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Watermelons are fruits that belong to the family cucurbitaceous. There are many types of watermelons have been positively identified to exist in the world. A watermelon consists of four distinct parts namely; seeds, pink flesh, white flesh and peel. It also contains high content of water of approximately 90% that is rich in essential minerals such as, phosphorous, calcium, magnesium, and potassium, sodium trace amounts of copper, iron, zinc and selenium. Watermelons have substantial amounts of boron, iodine, chromium, silicon and molybdenum. The levels of nutrients in different parts of the watermelons may be different. Selenium has been found to be a very useful food supplement especially for people living with HIV/AIDS. An experimental study was carried out to estimate the amount Se in different parts of the watermelon. Analysis of sampled watermelons was conducted using atomic absorption spectrophotometer. The results of the study indicated that high content of Se was present in the seeds compared to the other parts. High content of Se was also found in the water contained in the watermelon seeds.

Keywords: food supplement, watermelons, HIV/AIDS, nutrition, fruits

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12920 Impact of HIV/AIDS on Food Security in Pala Sub-Location, Bondo District, Kenya

Authors: S. B. Otieno, Were Fred, E. W. Kabiru, K. Waza

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Background: HIV/AIDS is leading to the loss of labor through sickness and subsequent death, this is leading to the neglect of farm and off-farm activities, with the subsequent loss of potential income and food security. The situation is sensitive to seasonal labour peaks in agriculture. This study was done to determine the impact of high HIV prevalence in farming systems and food security in Pala Bondo District, Kenya. Methods: In this study, 386 respondents were randomly chosen in Pala Sub-Location. The respondents and key informants were interviewed using structured questionnaire. The data were entered and analyzed using SPSS version 16. Results: It was established that majority of respondents (67%) were between 18 and 35 years {χ2 = (1, N = 386) = 13.430, p = 0.000} (chimney effect). The study also established that 83.5% of respondents were married {χ2 = (1, N= 370) = 166.277 p = 0.000} and predominant occupation being farming and fishing (61%), while 52.8% of farm labour was by hand, 26% by oxen, and 4.9% mechanized. 73.2% of respondents only farm 0.25 to 2 acres, 48% mentioned lack of labour in land preparation {χ2 ((1,N = 321) = 113.146, p = 0.000), in planting {χ2 (1, N = 321) = 29.28, p = 0.000}. Majority of respondents lack food from January to June, during which 93% buy food. Conclusion: The high HIV prevalence in Pala has affected the farm labour leading to food insecurity.

Keywords: food security, HIV, AIDS, labour

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12919 Sustainable Building Law - The Legal Issues Abound

Authors: Richard J. Sobelsohn

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Green Building and Sustainable Development help fight climate change, and protects the ozone, animal habitats, air quality, and ground water. The myriad of reasons to go Green has multiplied to the point that a developer that is building a ground-up or renovating/retrofitting a property has a plethora of choices to get to the green goal post. Sustainability not affects the bottom line but satisfies corporate mandates (ESG), consumer demand, market requirements, and the many laws dictating green building practices. The good news is that there are many paths a property owner can take to become green. The bad news is that there are many paths a property owner can take to become green, and they need to choose which direction to take. Certification of a building used to be the highest achievement in the Green building world. Now there are so many variables and laws with which a property owner must comply, and the legal analysis has mushroomed. Operation and Maintenance have also become one of the most important functions for a prudent Green Building owner. So adding to the “development/retrofit” parties involved in the sustainable building legal world, we now need to include all those people who keep the building green, and there are a lot of them!

Keywords: green building, sustainable development, legal issues, greenwashing, green cleaning, compliance, ESQ

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12918 Semantic Platform for Adaptive and Collaborative e-Learning

Authors: Massra M. Sabeima, Myriam lamolle, Mohamedade Farouk Nanne

Abstract:

Adapting the learning resources of an e-learning system to the characteristics of the learners is an important aspect to consider when designing an adaptive e-learning system. However, this adaptation is not a simple process; it requires the extraction, analysis, and modeling of user information. This implies a good representation of the user's profile, which is the backbone of the adaptation process. Moreover, during the e-learning process, collaboration with similar users (same geographic province or knowledge context) is important. Productive collaboration motivates users to continue or not abandon the course and increases the assimilation of learning objects. The contribution of this work is the following: we propose an adaptive e-learning semantic platform to recommend learning resources to learners, using ontology to model the user profile and the course content, furthermore an implementation of a multi-agent system able to progressively generate the learning graph (taking into account the user's progress, and the changes that occur) for each user during the learning process, and to synchronize the users who collaborate on a learning object.

Keywords: adaptative learning, collaboration, multi-agent, ontology

Procedia PDF Downloads 176
12917 High Efficiency Achievement by a New Heterojunction N-Zno:Al/P-Si Solar Cell

Authors: A. Bouloufa, F. Khaled, K. Djessas

Abstract:

This paper presents a new structure of solar cell based on p-type microcrystalline silicon as an absorber and n-type aluminum doped zinc oxide (ZnO:Al) transparent conductive oxide as an optical window. The ZnO:Al layer deposited by rf-magnetron sputtering at room temperature yields a low resistivity about 7,64.10-2Ω.cm and more than 85% mean optical transmittance in the VIS–NIR range, with an optical band gap of 3.3 eV. These excellent optical properties of this layer in combination with an optimal contact at the front surface result in a superior light trapping yielding to efficiencies about 20%. In order to improve efficiency, we have used a p+-µc-Si thin layer highly doped as a back surface field which minimizes significantly the impact of rear surface recombination velocity on voltage and current leading to a high efficiency of 24%. Optoelectronic parameters were determined using the current density-voltage (J-V) curve by means of a numerical simulation with Analysis of Microelectronic and Photonic Structures (AMPS-1D) device simulator.

Keywords: optical window, thin film, solar cell, efficiency

Procedia PDF Downloads 287
12916 Increase in the Shelf Life Anchovy (Engraulis ringens) from Flaying then Bleeding in a Sodium Citrate Solution

Authors: Santos Maza, Enzo Aldoradin, Carlos Pariona, Eliud Arpi, Maria Rosales

Abstract:

The objective of this study was to investigate the effect of flaying then bleeding anchovy (Engraulis ringens) immersed within a sodium citrate solution. Anchovy is a pelagic fish that readily deteriorates due to its high content of polyunsaturated fatty acids. As such, within the Peruvian food industry, the shelf life of frozen anchovy is explicitly 6 months, this short duration imparts a barrier to use for direct consumption human. Thus, almost all capture of anchovy by the fishing industry is eventually used in the production of fishmeal. We offer this an alternative to its typical production process in order to increase shelf life. In the present study, 100 kg of anchovies were captured and immediately mixed with ice on ship, maintaining a high quality sensory metric (e.g., with color blue in back) while still arriving for processing less than 2 h after capture. Anchovies with fat content of 3% were immediately flayed (i.e., reducing subcutaneous fat), beheaded, gutted and bled (i.e., removing hemoglobin) by immersion in water (Control) or in a solution of 2.5% sodium citrate (treatment), then subsequently frozen at -30 °C for 8 h in 2 kg batches. Subsequent glazing and storage at -25 °C for 14 months completed the experiments parameters. The peroxide value (PV), acidity (A), fatty acid profile (FAP), thiobarbituric acid reactive substances (TBARS), heme iron (HI), pH and sensory attributes of the samples were evaluated monthly. The results of the PV, TBARS, A, pH and sensory analyses displayed significant differences (p<0.05) between treatment and control sample; where the sodium citrate treated samples showed increased preservation features. Specifically, at the beginning of the study, flayed, beheaded, gutted and bled anchovies displayed low content of fat (1.5%) with moderate amount of PV, A and TBARS, and were not rejected by sensory analysis. HI values and FAP displayed varying behavior, however, results of HI did not reveal a decreasing trend. This result is indicative of the fact that levels of iron were maintained as HI and did not convert into no heme iron, which is known to be the primary catalyst of lipid oxidation in fish. According to the FAP results, the major quantity of fatty acid was of polyunsaturated fatty acid (PFA) followed by saturated fatty acid (SFA) and then monounsaturated fatty acid (MFA). According to sensory analysis, the shelf life of flayed, beheaded and gutted anchovy (control and treatment) was 14 months. This shelf life was reached at laboratory level because high quality anchovies were used and immediately flayed, beheaded, gutted, bled and frozen. Therefore, it is possible to maintain the shelf life of anchovies for a long time. Overall, this method displayed a large increase in shelf life relative to that commonly seen for anchovies in this industry. However, these results should be extrapolated at industrial scales to propose better processing conditions and improve the quality of anchovy for direct human consumption.

Keywords: citrate sodium solution, heme iron, polyunsaturated fatty acids, shelf life of frozen anchovy

Procedia PDF Downloads 294
12915 Hybridization and Dynamic Performance Analysis of Three-Wheeler Electric Auto Rickshaw

Authors: Muhammad Asghar, A. I. Bhatti, T. Izhar

Abstract:

The three-wheeled auto-rickshaw with a two or four-stroke Gasoline, Liquid Petrolium Gas (LPG) or Compressed Natural Gas (CNG) engine is a petite, highly maneuverable vehicle and best suited for the small and heavily-congested roads and is an affordable means of transportation in Pakistan cities. However due to in-efficient engine design, it is a main cause of air-pollution in the shape of white smoke (CO2) (greenhouse gases) at the tail pipe. Due to the environmental pollution, a huge number of battery powered vehicles have been imported from all over the world to fulfill the need of country. Effect of degree of hybridization on fuel economy and acceleration performance has been discussed in this paper. From mild to full hybridization stages have been examined. Optimal level of hybridization ranges depending on the total driving power of vehicle are suggested. The degree of hybridization is varied and fuel economy is seen accordingly by using Advisor (NREL) software. The novel vehicle drive-train is modeled and simulated in the Advisor software.

Keywords: advisor, hybridization, fuel economy, Three-Wheeled Rickshaw

Procedia PDF Downloads 567
12914 Energy Efficient Resource Allocation and Scheduling in Cloud Computing Platform

Authors: Shuen-Tai Wang, Ying-Chuan Chen, Yu-Ching Lin

Abstract:

There has been renewal of interest in the relation between Green IT and cloud computing in recent years. Cloud computing has to be a highly elastic environment which provides stable services to users. The growing use of cloud computing facilities has caused marked energy consumption, putting negative pressure on electricity cost of computing center or data center. Each year more and more network devices, storages and computers are purchased and put to use, but it is not just the number of computers that is driving energy consumption upward. We could foresee that the power consumption of cloud computing facilities will double, triple, or even more in the next decade. This paper aims at resource allocation and scheduling technologies that are short of or have not well developed yet to reduce energy utilization in cloud computing platform. In particular, our approach relies on recalling services dynamically onto appropriate amount of the machines according to user’s requirement and temporarily shutting down the machines after finish in order to conserve energy. We present initial work on integration of resource and power management system that focuses on reducing power consumption such that they suffice for meeting the minimizing quality of service required by the cloud computing platform.

Keywords: cloud computing, energy utilization, power consumption, resource allocation

Procedia PDF Downloads 339
12913 Microbiological Profile and Surgical Outcomes of Microbial Keratitis Associated Endophthalmitis

Authors: Prachi Abhishek Dave, Manisha Singh

Abstract:

Purpose: The purpose is to study the microbiological profile, prognostic factors, and outcomes of surgery for microbial keratitis (MK) associated endophthalmitis. Methods: It is a retrospective analysis of 39 MK associated endophthalmitis cases which underwent combined PKP with VR surgery. Results: The majority (84.6%) of patients had a history of previous ocular surgery, cataract surgery being the most common (51.2%). Six patients had a history of trauma and 8 patients had corneal graft infection. The culture positivity rate was 92.3%. Organisms isolated were Streptococcal sp (20.5%), Pseudomonas (15.3%), Staphylococcal sp (12.8%) and Fungus (35.8%). Final visual acuities ranged from NPL to 20/120. Poor anatomic success was seen in 15(38.46%) eyes (9-phthisis, 6-eviscerated). Fungal cases had a poor success rate (P-0.02). Conclusion: MK associated endophthalmitis is a sight threatening ocular condition. Fungal etiology carries a poorer prognosis. Timely surgical intervention can achieve favourable anatomical and functional results.

Keywords: endophthalmitis, microbial keratitis, penetrating keratoplasty, vitreo retinal surgery

Procedia PDF Downloads 46
12912 Deconstructing the Dialectics of Gender: An Analysis of Nigerian Igbo Women's Writing

Authors: R. Vidhya

Abstract:

Nigeria, the seat of canonical literature in Africa, though widely acclaimed as the literary capital of the continent, it failed to produce women writers in its literary arena till the 1960s. Only after 1966, with the publication of the first novel by a women writer, Nigeria saw the emergence of women’s writing through which the world witnessed an upsurge in the sensitization of women’s issues in Africa. The Nigerian Igbo women’s writing threw light on gender discrimination in postcolonial Africa. Their works were instrumental in bringing a remarkable change in the perception of gender in a male dominated society. The social mindscape of the land which strongly believed that feminist ideologies could be highly detrimental to its patriarchal setup is slowly changed through the changing perspectives of gender. This paper aims to analyse the select works of Flora Nwapa, Buchi Emecheta and Chimamanda Ngozi Adichie to deconstruct the dialectics of gender, which has been realised in the works of these women writers.

Keywords: gender discrimination, Igbo women's writings, postcolonial Africa, changing perspective

Procedia PDF Downloads 384