Search results for: production efficiency
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 12706

Search results for: production efficiency

4726 Channel Sounding and PAPR Reduction in OFDM for WiMAX Using Software Defined Radio

Authors: B. Siva Kumar Reddy, B. Lakshmi

Abstract:

WiMAX is a high speed broadband wireless access technology that adopted OFDM/OFDMA techniques to supply higher data rates with high spectral efficiency. However, OFDM suffers in view of high Peak to Average Power Ratio (PAPR) and high affect to synchronization errors. In this paper, the high PAPR problem is solved by using phase modulation to get Constant Envelop Orthogonal Frequency Division Multiplexing (CE-OFDM). The synchronization failures are brought down by employing a frequency lock loop, Poly phase clock synchronizer, Costas loop and blind equalizers such as Constant Modulus Algorithm (CMA) equalizer and Sign Kurtosis Maximization Adaptive Algorithm (SKMAA) equalizers. The WiMAX physical layer is executed on Software Defined Radio (SDR) prototype by utilizing USRP N210 as hardware and GNU Radio as software plat-forms. A SNR estimation is performed on the signal received through USRP N210. To empathize wireless propagation in specific environments, a sliding correlator wireless channel sounding system is designed by using SDR testbed.

Keywords: BER, CMA equalizer, Kurtosis equalizer, GNU Radio, OFDM/OFDMA, USRP N210

Procedia PDF Downloads 335
4725 Reliability and Validity of Determining Ventilatory Threshold and Respiratory Compensation Point by Near-Infrared Spectroscopy

Authors: Tso-Yen Mao, De-Yen Liu, Chun-Feng Huang

Abstract:

Purpose: This research intends to investigate the reliability and validity of ventilatory threshold (VT) and respiratory compensation point (RCP) determined by skeletal muscle hemodynamic status. Methods: One hundred healthy male (age: 22±3 yrs; height: 173.1±6.0 cm; weight: 67.1±10.5 kg) performed graded cycling exercise test which ventilatory and skeletal muscle hemodynamic data were collected simultaneously. VT and RCP were determined by combined V-slope (VE vs. VCO2) and ventilatory efficiency (VE/VO2 vs. VE/VCO2) methods. Pearson correlation, paired t-test, and Bland-Altman plots were used to analyze reliability, validity, and similarities. Statistical significance was set at α =. 05. Results: There are high test-retest correlations of VT and RCP in ventilatory or near-infrared spectroscopy (NIRS) methods (VT vs. VTNIRS: 0.95 vs. 0.94; RCP vs. RCPNIRS: 0.93 vs. 0.93, p<. 05). There are high coefficient of determination at the first timing point of O2Hb decreased (R2 = 0.88, p<. 05) with VT, and high coefficient of determination at the second timing point of O2Hb declined (R2 = 0.89, p< .05) with RCP. VO2 of VT and RCP are not significantly different between ventilatory and NIRS methods (p>. 05). Conclusion: Using NIRS method to determine VT and RCP is reliable and valid in male individuals during graded exercise. Non-invasive skeletal muscle hemodynamics monitor also can be used for controlling training intensity in the future.

Keywords: anaerobic threshold, exercise intensity, hemodynamic, NIRS

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4724 Computational Study on the Crystal Structure, Electronic and Optical Properties of Perovskites a2bx6 for Photovoltaic Applications

Authors: Harmel Meriem

Abstract:

The optoelectronic properties and high power conversion efficiency make lead halide perovskites ideal material for solar cell applications. However, the toxic nature of lead and the instability of organic cation are the two key challenges in the emerging perovskite solar cells. To overcome these challenges, we present our study about finding potential alternatives to lead in the form of A2BX6 perovskite using the first principles DFT-based calculations. The highly accurate modified Becke Johnson (mBJ) and hybrid functional (HSE06) have been used to investigate the Main Document Click here to view linked References to optoelectronic and thermoelectric properties of A2PdBr6 (A = K, Rb, and Cs) perovskite. The results indicate that different A-cations in A2PdBr6 can significantly alter their electronic and optical properties. Calculated band structures indicate semiconducting nature, with band gap values of 1.84, 1.53, and 1.54 eV for K2PdBr6, Rb2PdBr6, and Cs2PdBr6, respectively. We find strong optical absorption in the visible region with small effective masses for A2PdBr6. The ideal band gap and optimum light absorption suggest Rb2PdBr6 and Cs2PdBr6 potential candidates for the light absorption layer in perovskite solar cells. Additionally.

Keywords: soler cell, double perovskite, optoelectronic properties, ab-inotio study

Procedia PDF Downloads 108
4723 Induction Heating and Electromagnetic Stirring of Bi-Phasic Metal/Glass Molten Bath for Mixed Nuclear Waste Treatment

Authors: P. Charvin, R. Bourrou, F. Lemont, C. Lafon, A. Russello

Abstract:

For nuclear waste treatment and confinement, a specific IN-CAN melting module based on low-frequency induction heating have been designed. The frequency of 50Hz has been chosen to improve penetration length through metal. In this design, the liquid metal, strongly stirred by electromagnetic effects, presents shape of a dome caused by strong Laplace forces developing in the bulk of bath. Because of a lower density, the glass phase is located above the metal phase and is heated and stirred by metal through interface. Electric parameters (Intensity, frequency) give precious information about metal load and composition (resistivity of alloy) through impedance modification. Then, power supply can be adapted to energy transfer efficiency for suitable process supervision. Modeling of this system allows prediction of metal dome shape (in agreement with experimental measurement with a specific device), glass and metal velocity, heat and motion transfer through interface. MHD modeling is achieved with COMSOL and Fluent. First, a simplified model is used to obtain the shape of the metal dome. Then the shape is fixed to calculate the fluid flow and the thermal part.

Keywords: electromagnetic stirring, induction heating, interface modeling, metal load

Procedia PDF Downloads 246
4722 Growth Performance of New Born Holstein Calves Supplemented with Garlic (Allium sativum) Powder and Probiotics

Authors: T. W. Kekana, J. J. Baloyi, M. C. Muya, F. V. Nherera

Abstract:

Secondary metabolites (thiosulphinates) from Allium sativum are able to stimulate the production of volatile fatty acids. This study was carried out to investigate the effects of feeding Garlic powder or probiotics or a combination of both on feed intake and growth performance of Holstein calves. Neonatal calves were randomly allocated, according to birth weight, to four dietary treatments, each with 8 calves. The treatments were: C control, no additive (C), G: supplemented with either 5g/d garlic powder (G) or 4 g/d probiotics (P) or GP 5g/d garlic powder and 4 g/d probiotics compound (GP) with the total viable count of 1.3 x 107 cfu/g. Garlic and probiotics were diluted in the daily milk allocation from day 4. Commercial (17.5% CP) starter feed and fresh water were available ad libitum from day 4 until day 42 of age. Calves fed GP (0.27 kg day-1) tended (P=0.055) to have higher DMI than C (0.22 kg day-1). Milk, water, CP, fat intake and FCR were not affected (P>0.05) by the treatments. Metibolisable energy (ME) intake for GP group tended (P=0.058) to be higher than C calves. Combination of G and P (60.3 kg) tended (P = 0.056) to be higher than C (56.0 kg) calves on final BW. Garlic, probiotics or their combination did not affect calve’s HG, ADG and BL (P>0.05). The results of the current study indicated that combination of garlic and probiotics may improve nutrients intake and body weight when fed to calves during the first 42 days of life.

Keywords: garlic powder, probiotics, intake, growth, Holstein calves

Procedia PDF Downloads 649
4721 Phytochemical Analysis and in vitro Biological Activities of an Ethyl Acetate Extract from the Peel of Punica granatum L. var. Dente di Cavallo

Authors: Silvia Di Giacomo, Marcello Locatelli, Simone Carradori, Francesco Cacciagrano, Chiara Toniolo, Gabriela Mazzanti, Luisa Mannina, Stefania Cesa, Antonella Di Sotto

Abstract:

Hyperglycemia represents the main pathogenic factor in the development of diabetes complications and has been found associated with mitochondrial dysfunction and oxidative stress, which in turn increase cell dysfunction. Therefore, counteract oxidative species appears to be a suitable strategy for preventing the hyperglycemia-induce cell damage and support the pharmacotherapy of diabetes and metabolic diseases. Antidiabetic potential of many food sources has been linked to the presence of polyphenolic metabolites, particularly flavonoids such as quercetin and its glycosylated form rutin. In line with this evidence, in the present study, we assayed the potential anti-hyperglycemic activity of an ethyl acetate extract from the peel of Punica granatum L. var. Dente di Cavallo (PGE), a fruit well known to traditional medicine for the beneficial properties of its edible juice. The effect of the extract on the glucidic metabolism has been evaluated by assessing its ability to inhibit α-amylase and α-glucosidase, two digestive enzymes responsible for the hydrolysis of dietary carbohydrates: their inhibition can delay the carbohydrate digestion and reduce glucose absorption, thus representing an important strategy for the management of hyperglycemia. Also, the PGE ability to block the release of advanced glycated end-products (AGEs), whose accumulation is known to be responsible for diabetic vascular complications, was studied. The iron-reducing and chelating activities, which are the primary mechanisms by which AGE inhibitors stop their metal-catalyzed formation, were evaluated as possible antioxidant mechanisms. At last, the phenolic content of PGE was characterized by chromatographic and spectrophotometric methods. Our results displayed the ability of PGE to inhibit α-amylase enzyme with a similar potency to the positive control: the IC₅₀ values were 52.2 (CL 27.7 - 101.2) µg/ml and 35.6 (CL 22.8 - 55.5) µg/ml for acarbose and PGE, respectively. PGE also inhibited the α-glucosidase enzyme with about a 25 higher potency than the positive controls of acarbose and quercetin. Furthermore, the extract exhibited ferrous and ferric ion chelating ability, with a maximum effect of 82.1% and 80.6% at a concentration of 250 µg/ml respectively, and reducing properties, reaching the maximum effect of 80.5% at a concentration of 10 µg/ml. At last, PGE was found able to inhibit the AGE production (maximum inhibition of 82.2% at the concentration of 1000 µg/ml), although with lower potency with respect to the positive control rutin. The phytochemical analysis of PGE displayed the presence of high levels of total polyphenols, tannins, and flavonoids, among which ellagic acid, gallic acid and catechin were identified. Altogether these data highlight the ability of PGE to control the carbohydrate metabolism at different levels, both by inhibiting the metabolic enzymes and by affecting the AGE formation likely by chelating mechanisms. It is also noteworthy that peel from pomegranate, although being a waste of juice production, can be reviewed as a nutraceutical source. In conclusion, present results suggest the possible role of PGE as a remedy for preventing hyperglycemia complications and encourage further in vivo studies.

Keywords: anti-hyperglycemic activity, antioxidant properties, nutraceuticals, polyphenols, pomegranate

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4720 Comparative Analysis of Enzyme Activities Concerned in Decomposition of Toluene

Authors: Ayuko Itsuki, Sachiyo Aburatani

Abstract:

In recent years, pollutions of the environment by toxic substances become a serious problem. While there are many methods of environmental clean-up, the methods by microorganisms are considered to be reasonable and safety for environment. Compost is known that it catabolize the meladorous substancess in its production process, however the mechanism of its catabolizing system is not known yet. In the catabolization process, organic matters turn into inorganic by the released enzymes from lots of microorganisms which live in compost. In other words, the cooperative of activated enzymes in the compost decomposes malodorous substances. Thus, clarifying the interaction among enzymes is important for revealing the catabolizing system of meladorous substance in compost. In this study, we utilized statistical method to infer the interaction among enzymes. We developed a method which combined partial correlation with cross correlation to estimate the relevance between enzymes especially from time series data of few variables. Because of using cross correlation, we can estimate not only the associative structure but also the reaction pathway. We applied the developed method to the enzyme measured data and estimated an interaction among the enzymes in decomposition mechanism of toluene.

Keywords: enzyme activities, comparative analysis, compost, toluene

Procedia PDF Downloads 255
4719 Industrial Investment and Contract Models in Subway Projects: Case Study

Authors: Seyed Habib A. Rahmati, Parsa Fallah Sheikhlari, Morteza Musakhani

Abstract:

This paper studies the structure of financial investment and efficiency on the subway would be created between Hashtgerd and Qazvin in Iran. Regarding ascending rate of transportation between Tehran and Qazvin which directly air pollution, it clearly implies to public transportation requirement between these two cities near Tehran. The railway transportation like subway can help each country to terminate traffic jam which has some advantages such as speed, security, non-pollution, low cost of public transport, etc. This type of transportation needs national infrastructures which require enormous investment. It couldn’t implement without leading and managing funds and investments properly. In order to response 'needs', clear norms or normative targets have to be agreed and obviously it is important to distinguish costs from investment requirements critically. Implementation phase affects investment requirements and financing needs. So recognizing barrier related to investment and the quality of investment (what technologies and services are invested in) is as important as the amounts of investment. Different investment methods have mentioned as follows loan, leasing, equity participation, Line of financing, finance, usance, bay back. Alternatives survey before initiation and analyzing of risk management is one of the most important parts in this project. Observation of similar project cities each country has the own specification to choose investment method.

Keywords: subway project, project investment, project contract, project management

Procedia PDF Downloads 465
4718 Final Costs of Civil Claims

Authors: Behnam Habibi Dargah

Abstract:

The economics of cost-benefit theory seeks to monitor claims and determine their final price. The cost of litigation is important because it is a measure of the efficiency of the justice system. From an economic point of view, the cost of litigation is considered to be the point of equilibrium of litigation, whereby litigation is regarded as a high-risk investment and is initiated when the costs are less than the probable and expected benefits. Costs are economically separated into private and social costs. Private cost includes material (direct and indirect) and spiritual costs. The social costs of litigation are also subsidized-centric due to the public and governmental nature of litigation and cover both types of bureaucratic bureaucracy and the costs of judicial misconduct. Macroeconomic policy in the economics of justice is the reverse engineering of controlling the social costs of litigation by employing selective litigation and working on the judicial culture to achieve rationality in the monopoly system. Procedures for controlling and managing court costs are also circumscribed to economic patterns in the field. Rational cost allocation model and cost transfer model. The rational allocation model deals with cost-tolerance systems, and the transfer model also considers three models of transferability, including legal, judicial and contractual transferability, which will be described and explored in the present article in a comparative manner.

Keywords: cost of litigation, economics of litigation, private cost, social cost, cost of litigation

Procedia PDF Downloads 112
4717 Targeting Basic Leucine Zipper Transcription Factor ATF-Like Mediated Immune Cells Regulation to Reduce Crohn’s Disease Fistula Incidence

Authors: Mohammadjavad Sotoudeheian, Soroush Nematollahi

Abstract:

Crohn’s disease (CD) is a chronic gastrointestinal segment inflammation encompassing immune dysregulation in a genetically susceptible individual in response to the environmental triggers and interaction between the microbiome and immune system. Uncontrolled inflammation leads to long-term complications, including fibrotic strictures and enteric fistulae. Increased production of Th1 and Th17-cell cytokines and defects in T-regulatory cells have been associated with CD. Th17-cells are essential for protection against extracellular pathogens, but their atypical activity can cause autoimmunity. Intrinsic defects in the control of programmed cell death in the mucosal T-cell compartment are strongly implicated in the pathogenesis of CD. The apoptosis defect in mucosal T-cells in CD has been endorsed as an imbalance of the Bcl-2 and the Bax. The immune system encounters foreign antigens through microbial colonization of mucosal surfaces or infections. In addition, FOSL downregulated IL-26 expression, a cytokine that marks inflammatory Th17-populations in patients suffering from CD. Furthermore, the expression of IL-23 is associated with the transcription factor primary leucine zipper transcription factor ATF-like (Batf). Batf-deficiency demonstrated the crucial role of Batf in colitis development. Batf and IL-23 mediate their effects by inducing IL-6 production. Strong association of IL-23R, Stat3, and Stat4 with IBD susceptibility point to a critical involvement of T-cells. IL-23R levels in transfer fistula were dependent on the AP-1 transcription factor JunB that additionally controlled levels of RORγt by facilitating DNA binding of Batf. T lymphocytes lacking JunB failed to induce IL-23- and Th17-mediated experimental colitis highlighting the relevance of JunB for the IL-23/ Th17 pathway. The absence of T-bet causes unrestrained Th17-cell differentiation. T-cells are central parts of immune-mediated colon fistula. Especially Th17-cells were highly prevalent in inflamed IBD tissues, as RORγt is effective in preventing colitis. Intraepithelial lymphocytes (IEL) contain unique T-cell subsets, including cells expressing RORγt. Increased activated Th17 and decreased T-regulatory cells in inflamed intestinal tissues had been seen. T-cells differentiate in response to many cytokines, including IL-1β, IL-6, IL-23, and TGF-β, into Th17-cells, a process which is critically dependent on the Batf. IL-23 promotes Th17-cell in the colon. Batf manages the generation of IL-23 induced IL-23R+ Th17-cells. Batf is necessary for TGF-β/IL-6-induced Th17-polarization. Batf-expressing T-cells are the core of T-cell-mediated colitis. The human-specific parts of three AP-1 transcription factors, FOSL1, FOSL2, and BATF, are essential during the early stages of Th17 differentiation. BATF supports the Th17 lineage. FOSL1, FOSL2, and BATF make possession of regulatory loci of genes in the Th17 lineage cascade. The AP1 transcription factor Batf is identified to control intestinal inflammation and seems to regulate pathways within lymphocytes, which could theoretically control the expression of several genes. It shows central regulatory properties over Th17-cell development and is intensely upregulated within IBD-affected tissues. Here, we demonstrated that targeting Batf in IBD appears as a therapeutic approach that reduces colitogenic T-cell activities during fistula formation while aiming to affect inflammation in the gut epithelial cells.

Keywords: immune system, Crohn’s Disease, BATF, T helper cells, Bcl, interleukin, FOSL

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4716 Factors Influencing the Development and Implementation of Radiology Technologist Specialist Role in Image Interpretation in Sudan

Authors: Awad Elkhadir, Rajab M. Ben Yousef

Abstract:

Introduction: The production of high-quality medical images by radiology technologists is useful in diagnosing and treating various injuries and diseases. However, the factors affecting the role of radiology technologists in image interpretation in Sudan have not been investigated widely. Methods: Cross-sectional study has been employed by recruiting ten radiology college deans in Sudan. The questionnaire was distributed online, and obtained data were analyzed using Microsoft Excel and IBM-SPSS version 16.0 to generate descriptive statistics. Results: The study results have shown that half of the deans were doubtful about the readiness of Sudan to implement the role of radiology technologist specialist in image interpretation. The majority of them (60%) believed that this issue had been most strongly pushed by researchers over the past decade. The factors affecting the implementation of the radiology technologist specialist role in image interpretation included; education/training (100%), recognition (30%), technical issues (30%), people-related issues (20%), management changes (30%), government role (30%), costs (10%), and timings (20%). Conclusion: The study concluded that there is a need for a change in image interpretation by radiology technologists in Sudan.

Keywords: development, image interpretation, implementation, radiology technologist specialist, Sudan

Procedia PDF Downloads 78
4715 Increasing Business Competitiveness in Georgia in Terms of Globalization

Authors: Badri Gechbaia, Levan Gvarishvili

Abstract:

Despite the fact that a lot of Georgian scientists have worked on the issue of the business competitiveness, it think that it is necessary to deepen the works in this sphere, it is necessary also to perfect the methodology in the estimation of the business competitiveness, we have to display the main factors which define the competitive advantages in the business sphere, we have also to establish the interconnections between the business competitiveness level and the quality of states economical involvement in the international economic processes, we have to define the ways to rise the business competitiveness and its role in the upgrading of countries economic development. The introduction part justifies the actuality of the studied topic and the thesis; It defines the survey subject, the object, and the goals with relevant objectives; theoretical-methodological and informational-statistical base for the survey; what is new in the survey and what the value for its theoretical and practical application is. The aforementioned study is an effort to raise public awareness on this issue. Analysis of the fundamental conditions for the efficient functioning of business in Georgia, identification of reserves for increasing its efficiency based on the assessment of the strengths and weaknesses of the business sector. Methods of system analysis, abstract-logic, induction and deduction, synthesis and generalization, and positive, normative, and comparative analysis are used in the research process. Specific regularities of the impact of the globalization process on the determinants of business competitiveness are established. The reasons for business competitiveness in Georgia have been identified

Keywords: competitiveness, methodology, georgian, economic

Procedia PDF Downloads 94
4714 Different Sampling Schemes for Semi-Parametric Frailty Model

Authors: Nursel Koyuncu, Nihal Ata Tutkun

Abstract:

Frailty model is a survival model that takes into account the unobserved heterogeneity for exploring the relationship between the survival of an individual and several covariates. In the recent years, proposed survival models become more complex and this feature causes convergence problems especially in large data sets. Therefore selection of sample from these big data sets is very important for estimation of parameters. In sampling literature, some authors have defined new sampling schemes to predict the parameters correctly. For this aim, we try to see the effect of sampling design in semi-parametric frailty model. We conducted a simulation study in R programme to estimate the parameters of semi-parametric frailty model for different sample sizes, censoring rates under classical simple random sampling and ranked set sampling schemes. In the simulation study, we used data set recording 17260 male Civil Servants aged 40–64 years with complete 10-year follow-up as population. Time to death from coronary heart disease is treated as a survival-time and age, systolic blood pressure are used as covariates. We select the 1000 samples from population using different sampling schemes and estimate the parameters. From the simulation study, we concluded that ranked set sampling design performs better than simple random sampling for each scenario.

Keywords: frailty model, ranked set sampling, efficiency, simple random sampling

Procedia PDF Downloads 195
4713 The Impact of Content Familiarity of Receptive Skills on Language Learning

Authors: Sara Fallahi

Abstract:

This paper reviews the importance of content familiarity of receptive skills and offers solutions to the issue of content unfamiliarity in language learning materials. Presently, language learning materials are mainly comprised of global issues and target language speakers’ culture(s) in receptive skills. This might leadlearners to focus on content rather than the language. As a solution, materials on receptive skills can be developed with a focus on learners’culture and social concerns, especially in the beginner levels of learning. Language learners often learn their target language through the receptive skills of listening and reading before language production ensues through speaking and writing. Students’ journey from receptive skills to productive skills is mainly concentrated on by teachers. There are barriers to language learning, such as time and energy, that can hinder learners’ understanding and ability to build the required background knowledge of the content. This is generated due to learners’ unfamiliarity with the skill’s content. Therefore, materials that improve content familiarity will help learners improve their language comprehension, learning, and usage. This presentation will conclude with practical solutions to help teachers and learners more authentically integrate language and culture to elevate language learning.

Keywords: language learning, listening content, reading content, content familiarity, ESL books, language learning books, cultural familiarity

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4712 Water Management in Rice Plants of Dry Season in the Rainfed Lowland

Authors: Zainal Arifin, Mohammad Saeri

Abstract:

The purpose of this study is to determine the efficiency of irrigation use on the growth and yield of two varieties of rice. Water management research on rainfed lowland rice was carried out in dry season (DS I) 2016 in an area of 10,000 m2 in Bunbarat Village, Rubaru Subdistrict, Sumenep Regency. The research was randomized block design factorial with 8 treatments and repeated 3 times, ie Factor I (varieties): (a) Inpago 9, and (b) Sidenuk; factor II (irrigation): (a) Alternate Wetting and Drying, (b) intermittent, (c) submerged, and (d) inundated. The results showed that dominant weed species such as purslane (Portulaca oleraceae L.) and barnyard grass (Echinochloa crusgalli) were mostly found in rice cultivation with Alternate Wetting and Drying, intermittent and submerged irrigation treatment, while the lowest was inundated irrigation. The use of Sidenuk variety with Alternate Wetting and Drying irrigation yielded 5.7 t/ha dry grain harvest (dgh) and was not significantly different from the inundated watering using the Sidenuk variety (6.2 t/ha dgh). With Alternate Wetting and Drying irrigation technique, water use is more efficient as much as 1,503 m3/ha so as to produce 1 kg of grain, it needs 459 liters of water compared to inundated irrigation (665 liters/kg of grain). Results of analysis of rice farming Sidenuk variety with Alternate Wetting and Drying irrigation has the highest B/C ratio (2.56) so that economically feasible.

Keywords: water management, varieties, rice, dry season, rainfed lowland

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4711 Olive Leaf Extract as Natural Corrosion Inhibitor for Pure Copper in 0.5 M NaCl Solution: A Study by Voltammetry around OCP

Authors: Chahla Rahal, Philippe Refait

Abstract:

Oleuropein-rich extract from olive leaf and acid hydrolysates, rich in hydroxytyrosol and elenolic acid was prepared under different experimental conditions. These phenolic compounds may be used as a corrosion inhibitor. The inhibitive action of these extracts and its major constituents on the corrosion of copper in 0.5 M NaCl solution has been evaluated by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurements. The product of extraction was analyzed with high performance liquid chromatography (HPLC), whose analysis shows that olive leaf extract are greatly rich in phenolic compounds, mainly Oleuropeine (OLE), Hydroxytyrosol (HT) and elenolic acid (EA). After the acid hydrolysis and high temperature of extraction, an increase in hydroxytyrosol concentration was detected, coupled with relatively low oleuropeine content and high concentration of elenolic acid. The potentiodynamic measurements have shown that this extract acts as a mixed-type corrosion inhibitor, and good inhibition efficiency is observed with the increase in HT and EA concentration. These results suggest that the inhibitive effect of olive leaf extract might be due to the adsorption of the various phenolic compounds onto the copper surface.

Keywords: Olive leaf extract, Oleuropein, hydroxytyrosol, elenolic acid , Copper, Corrosion, HPLC/DAD, Polarisation, EIS

Procedia PDF Downloads 245
4710 A Combination of Filtration and Coagulation Processes for Tannery Effluent Treatment

Authors: M. G. Mostafa, Manjushree Chowdhury, Tapan Kumar Biswas, , Ananda Kumar Saha

Abstract:

This study focused on effluents characterization and treatment process to reduce of toxicity from tannery effluents. Tanning industry is one of the oldest industries in the world. It is typically characterized as pollutants generated industries which produce wide varieties of high strength toxic chemicals. The study was conducted during the year 2008 to 2009 and the tannery effluents were collected three times in a year from the outlet of some selected leather industries located in Hagaribagh industrial zone Dhaka, Bangladesh. The analysis results of the raw effluents reveal that the effluents were yellowish-brown color, having basic pH, very high value of BOD5¬¬, COD, TDS, TSS, TS, and high concentrations of Cr, Na, SO42-, Cl- and other organic and inorganic constituents. The tannery effluents were treated with various doses of FeCl3 after settling and a subsequent filtration through sand-stone. The study observed that coagulant (FeCl3) 150 mg/L dose around neutral pH showed the best removal efficiency for major physico-chemical parameters. The analysis results of illustrate that the most of the physical and chemical parameters were found well below the prescribed permissible limits for effluent discharged. The study suggests that tannery effluents could be treated by a combined process consisting of settling, filtering and coagulating with FeCl3.

Keywords: characterization, effluent, tannery, treatment

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4709 Essential Factors of Risk Perception Crucial in Efficient Construction Management

Authors: Francis Edum-Fotwe, Tony Thorpe, Charles Afetornu

Abstract:

Risk perception informs the outcome of how issues are responded to in either solving or overcoming a problem or improving a situation. Risk perception is established to be affected by some key factors reflecting in the varying ways in which work is done as well as the level of efficiency achieved. These factors potentially would influence risk perception to different extents. Such that if these factors are said to determine risk perception, how does a change in any affect risk perception. Since the ability to address risk is influenced by risk perception, establishing and developing awareness of that perception should enable construction professionals to make viable decisions. Any act to improve the construction industry cannot be overemphasised, considering its contribution to national development. A survey questionnaire was conducted in Ghana to elicit data that measures the risk perception and the essential factors as well as the necessary demographics of the respondents, who are construction professionals. This study finds out the sensitivity of the critical factors of risk perception. It uses the Relative Importance Index analysis tool to investigate the differential effect of these essential factors on risk perception, such that a slight change in a factor makes a significant change in risk perception, having established that it is influenced by essential factors. The findings can lead to policy formation for employers on the prioritisation factors to undertake to improve the risk perception of employees. Other areas in which this study can be useful in team formation for sensitive and complex projects where efficient risk management is critical.

Keywords: construction industry, risk, risk management, risk perception

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4708 A Variable Speed DC Motor Using a Converter DC-DC

Authors: Touati Mawloud

Abstract:

Between electronics and electrical systems has developed a new technology that is power electronics, also called electronic of strong currents, this application covers a very wide range of use particularly in the industrial sector, where direct current engines are frequently used, they control their speed by the use of the converters (DC-DC), which aims to deal with various mechanical disturbances (fillers) or electrical (power). In future, it will play a critical role in transforming the current electric grid into the next generation grid. Existing silicon-based PE devices enable electric grid functionalities such as fault-current limiting and converter devices. Systems of future are envisioned to be highly automated, interactive "smart" grid that can self-adjust to meet the demand for electricity reliability, securely, and economically. Transforming today’s electric grid to the grid of the future will require creating or advancing a number of technologies, tools, and techniques—specifically, the capabilities of power electronics (PE). PE devices provide an interface between electrical system, and electronics system by converting AC to direct current (DC) and vice versa. Solid-state wide Bandgap (WBG), semiconductor electronics (such as silicon carbide [SiC], gallium nitride [GaN], and diamond) are envisioned to improve the reliability and efficiency of the next-generation grid substantially.

Keywords: Power Electronics (PE), electrical system generation electric grid, switching frequencies, converter devices

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4707 Production of Antimicrobial Agents against Multidrug-Resistant Staphylococcus aureus through the Biocatalysis of Vegetable Oils

Authors: Hak-Ryul Kim, Hyung-Geun Lee, Qi Long, Ching Hou

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Structural modification of natural lipids via chemical reaction or microbial bioconversion can change their properties or even create novel functionalities. Enzymatic oxidation of lipids leading to formation of oxylipin is one of those modifications. Hydroxy fatty acids, one of those oxylipins have gained important attentions because of their structural and functional properties compared with other non-hydroxy fatty acids. Recently 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) was produced with high yield from lipid-containing oleic acid by microbial conversion, and the further study confirmed that DOD contained strong antimicrobial activities against a broad range of microorganisms. In this study, we tried to modify DOD molecules by the enzymatic or physical reaction to create new functionality or to enhance the antimicrobial activity of DOD. After modification of DOD molecules by different ways, we confirmed that the antimicrobial activity of DOD was highly enhanced and presented strong antimicrobial activities against multidrug-resistant Staphylococcus aureus, suggesting that DOD and its derivatives can be used as efficient antimicrobial agents for medical and industrial applications.

Keywords: biocatalysis, antimicrobial agent, multidrug-resistant bacteria, vegetable oil

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4706 Global Voltage Harmonic Index for Measuring Harmonic Situation of Power Grids: A Focus on Power Transformers

Authors: Alireza Zabihi, Saeed Peyghami, Hossein Mokhtari

Abstract:

With the increasing deployment of renewable power plants, such as solar and wind, it is crucial to measure the harmonic situation of the grid. This paper proposes a global voltage harmonic index to measure the harmonic situation of the power grid with a focus on power transformers. The power electronics systems used to connect these plants to the network can introduce harmonics, leading to increased losses, reduced efficiency, false operation of protective relays, and equipment damage due to harmonic intensifications. The proposed index considers the losses caused by harmonics in power transformers which are of great importance and value to the network, providing a comprehensive measure of the harmonic situation of the grid. The effectiveness of the proposed index is evaluated on a real-world distribution network, and the results demonstrate its ability to identify the harmonic situation of the network, particularly in relation to power transformers. The proposed index provides a comprehensive measure of the harmonic situation of the grid, taking into account the losses caused by harmonics in power transformers. The proposed index has the potential to support power companies in optimizing their power systems and to guide researchers in developing effective mitigation strategies for harmonics in the power grid.

Keywords: global voltage harmonic index, harmonics, power grid, power quality, power transformers, renewable energy

Procedia PDF Downloads 108
4705 Budget and the Performance of Public Enterprises: A Study of Selected Public Enterprises in Nasarawa State Nigeria (2009-2013)

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

Abstract:

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

Keywords: budget, public enterprises, revenue, enterprise

Procedia PDF Downloads 234
4704 Acoustic Characteristics of Ḫijaiyaḫ Letters Pronunciation by Indonesian Native Speaker

Authors: Romi Hardiyansyah, Raden Sugeng Joko Sarwono, Agus Samsi

Abstract:

Indonesian people have a mother language but not Arabic. Meanwhile, they must be able to pronounce the Arabic because Islam is the biggest religion in Indonesia. Arabic is composed by ḫijaiyaḫ letters which has its own pronunciation. Sound production process in humans can be divided into three physiological processes, namely: the formation of airflow from the lungs, the change in airflow from the lungs into the sound, and articulation (the modulation/sound setting into a specific sound). Ḫijaiyaḫ letters has its own articulation, some of which seem strange for most people in Indonesia. Those letters come out from the middle and upper throat so that the letters has its own acoustic characteristics. Acoustic characteristics of voice can be observed by source-filter approach that has parameters: pitch, formant, and formant bandwidth. Pitch is the basic tone in every human being. Formant is the resonance frequency of the human voice. Formant bandwidth is the time-width of a formant. After recording the sound from 21 subjects, data is processed by software Praat version 5.3.39. The analysis showed that each pronunciation, syakal (vowel changer), and the place of discharge letters has the same timbre which are determined by third and fourth formant.

Keywords: ḫijaiyaḫ, articulation, pitch, formant, formant bandwidth, timbre

Procedia PDF Downloads 379
4703 Admission Control Policy for Remanufacturing Activities with Quality Variation of Returns

Authors: Sajjad Farahani, Wilkistar Otieno, Xiaohang Yue

Abstract:

This paper develops a model for the optimal disposition decision for product returns in a remanufacturing system with limited recoverable inventory capacity. In this model, a constant demand is satisfied by remanufacturing returned products which are up to the minimum required quality grade. The quality grade of returned products is uncertain and remanufacturing cost increases as the quality level decreases, and remanufacturer wishes to determine which returned product to accept to be remanufactured for reselling, and any unaccepted returns may be salvaged at a value that increases with their quality level. Accepted returns can be stocked for remanufacturing upon demand requests, but incur a holding cost. A Markov decision problem is formulated in order to evaluate various performance measures for this system and obtain the optimal remanufacturing policy. A detailed numerical study reveals that our approach to the disposition problem outperforms the current industrial practice ignoring quality grade of returned products. In addition, we identify conditions under which this improvement is the highest.

Keywords: green supply chain management, matrix geometric method, production recovery, reverse supply chains

Procedia PDF Downloads 298
4702 Re-Designing Community Foodscapes to Enhance Social Inclusion in Sustainable Urban Environments

Authors: Carles Martinez-Almoyna Gual, Jiwon Choi

Abstract:

Urban communities face risks of disintegration and segregation as a consequence of globalised migration processes towards urban environments. Linking social and cultural components with environmental and economic dimensions becomes the goal of all the disciplines that aim to shape more sustainable urban environments. Solutions require interdisciplinary approaches and the use of a complex array of tools. One of these tools is the implementation of urban farming, which provides a wide range of advantages for creating more inclusive spaces and integrated communities. Since food is strongly related to the values and identities of any cultural group, it can be used as a medium to promote social inclusion in the context of urban multicultural societies. By bringing people together into specific urban sites, food production can be integrated into multifunctional spaces while addressing social, economic and ecological goals. The goal of this research is to assess different approaches to urban agriculture by analysing three existing community gardens located in Newtown, a suburb of Wellington, New Zealand. As a context for developing research, Newtown offers different approaches to urban farming and is really valuable for observing current trends of socialization in diverse and multicultural societies. All three spaces are located on public land owned by Wellington City Council and confined to a small, complex and progressively denser urban area. The developed analysis was focused on social, cultural and physical dimensions, combining community engagement with different techniques of spatial assessment. At the same time, a detailed investigation of each community garden was conducted with comparative analysis methodologies. This multidirectional setting of the analysis was established for extracting from the case studies both specific and typological knowledge. Each site was analysed and categorised under three broad themes: people, space and food. The analysis revealed that all three case studies had really different spatial settings, different approaches to food production and varying profiles of supportive communities. The main differences identified were demographics, values, objectives, internal organization, appropriation, and perception of the space. The community gardens were approached as case studies for developing design research. Following participatory design processes with the different communities, the knowledge gained from the analysis was used for proposing changes in the physical environment. The end goal of the design research was to improve the capacity of the spaces to facilitate social inclusiveness. In order to generate tangible changes, a range of small, strategic and feasible spatial interventions was explored. The smallness of the proposed interventions facilitates implementation by reducing time frames, technical resources, funding needs, and legal processes, working within the community´s own realm. These small interventions are expected to be implemented over time as part of an ongoing collaboration between the different communities, the university, and the local council. The applied research methodology showcases the capacity of universities to develop civic engagement by working with real communities that have concrete needs and face overall threats of disintegration and segregation.

Keywords: community gardening, landscape architecture, participatory design, placemaking, social inclusion

Procedia PDF Downloads 112
4701 Meteosat Second Generation Image Compression Based on the Radon Transform and Linear Predictive Coding: Comparison and Performance

Authors: Cherifi Mehdi, Lahdir Mourad, Ameur Soltane

Abstract:

Image compression is used to reduce the number of bits required to represent an image. The Meteosat Second Generation satellite (MSG) allows the acquisition of 12 image files every 15 minutes. Which results a large databases sizes. The transform selected in the images compression should contribute to reduce the data representing the images. The Radon transform retrieves the Radon points that represent the sum of the pixels in a given angle for each direction. Linear predictive coding (LPC) with filtering provides a good decorrelation of Radon points using a Predictor constitute by the Symmetric Nearest Neighbor filter (SNN) coefficients, which result losses during decompression. Finally, Run Length Coding (RLC) gives us a high and fixed compression ratio regardless of the input image. In this paper, a novel image compression method based on the Radon transform and linear predictive coding (LPC) for MSG images is proposed. MSG image compression based on the Radon transform and the LPC provides a good compromise between compression and quality of reconstruction. A comparison of our method with other whose two based on DCT and one on DWT bi-orthogonal filtering is evaluated to show the power of the Radon transform in its resistibility against the quantization noise and to evaluate the performance of our method. Evaluation criteria like PSNR and the compression ratio allows showing the efficiency of our method of compression.

Keywords: image compression, radon transform, linear predictive coding (LPC), run lengthcoding (RLC), meteosat second generation (MSG)

Procedia PDF Downloads 398
4700 Preliminary Findings from a Research Survey on Evolution of Software Defined Radio

Authors: M. Srilatha, R. Hemalatha, T. Sri Aditya

Abstract:

Communication of today world is dominated by wireless technology. This is mainly due to the revolutionary development of new wireless communication system generations. The evolving new generations of wireless systems are accommodating the demand through better resource management including improved transmission technologies with optimized communication devices. To keep up with the evolution of technologies, the communication systems must be designed to optimize transparent insertion of newly evolved technologies virtually at all stages of their life cycle. After the insertion of new technologies, the upgraded devices should continue the communication without squalor in quality. The concern of improving spectrum access and spectrum efficiency combined with both the introduction of Software Defined Radios (SDR) and the possibility of the software application to radios has led to an evolution of wireless radio research. The software defined radio term was coined in the 1970s to overcome the problems in the application of software to wireless radios which eliminates the requirement of hardware changes. SDR has become the prime theme of research since it eliminates the drawbacks associated with conventional wireless communication systems implementation. This paper identifies and discusses key enabling technologies and possibility of research and development in SDRs. In addition transmitter and receiver architectures of SDR are also discussed along with their feasibility for reconfigurable radio application.

Keywords: software defined radios, wireless communication, reconfigurable, reconfigurable transmitter, reconfigurable receivers, FPGA, DSP

Procedia PDF Downloads 301
4699 Mixed Alumina-Silicate Materials for Groundwater Remediation

Authors: Ziyad Abunada, Abir Al-tabbaa

Abstract:

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

Keywords: modified bentobite, groundwater, adsorption, contaminats

Procedia PDF Downloads 210
4698 A Proposed Model of E-Marketing Service-Oriented Architecture (E-MSOA)

Authors: Hussein Moselhy, Islam Salam

Abstract:

There have been some challenges and problems which hinder the implementation of the e-marketing systems such as the high cost of information systems infrastructure and maintenance as well as their unavailability within the institution. Also, there is no system which supports all programming languages and different platforms. Another problem is the lack of integration between these systems on one hand and the operating systems and different web browsers on the other hand. No system for customer relationship management is established which recognizes their desires and puts them in consideration while performing e-marketing functions is available. Therefore, the service-oriented architecture emerged as one of the most important techniques and methodologies to build systems that integrate with various operating systems and different platforms and other technologies. This technology allows realizing the data exchange among different applications. The service-oriented architecture represents distributed computing concepts to demonstrate its success in achieving the requirements of systems through web services. It also reflects the appropriate design for the services to use different web services in supporting the requirements of business processes and software users. In a service-oriented environment, web services are deployed on the web in the form of independent services to be accessed without knowledge of the nature of the programs and systems with in. This Paper presents a proposal for a new model which contributes to the application of methods and means of e-marketing with the integration of marketing mix elements to improve marketing efficiency (E-MSOA). And apply it in the educational city of one of the Egyptian sector.

Keywords: service-oriented architecture, electronic commerce, virtual retailing, unified modeling language

Procedia PDF Downloads 415
4697 Experimental Study for the Development of a Wireless Communication System in a Solar Central Tower Facility

Authors: Victor H. Benitez, Ramon V. Armas-Flores, Jesus H. Pacheco-Ramirez

Abstract:

Systems transforming solar energy into electrical power have emerged as a viable source of clean, renewable energy. Solar power tower technology is a good example of this type of system, which consists of several mobile mirrors, called heliostats, which reflect the sun's radiation to the same point, located on top of a tower at the center of heliostat field, for collection or transformation into another type of energy. The so-called Hermosillo’s Solar Platform (Plataforma Solar de Hermosillo, PSH, in Spanish) is a facility constituted with several heliostats, its aim and scope is for research purposes. In this paper, the implementation of a wireless communication system based on intelligent nodes is proposed in order to allow the communication and control of the heliostats in PSH. Intelligent nodes transmit information from one point to another, and can perform other actions that allow them to adapt to the conditions and limitations of a field of heliostats, thus achieving effective communication system. After deployment of the nodes in the heliostats, tests were conducted to measure the effectiveness of the communication, and determine the feasibility of using the proposed technologies. The test results were always positive, exceeding expectations held for its operation in the field of heliostats. Therefore, it was possible to validate the efficiency of the wireless communication system to be implemented in PSH, allowing communication and control of the heliostats.

Keywords: heliostat, intelligent node, solar energy, wireless communication

Procedia PDF Downloads 395