Search results for: crest factor reduction

Authors: Abdolamir Allameh, Seyyed Mortaza Haghgoo, Adnan Khosravi, Esmaeil Mortaz, Mihan Pourabdollah-Toutkaboni, Sharareh Seifi

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Non-Small Cell Lung Carcinoma (NSCLC) is associated with a number of gene mutations in epidermal growth factor receptor (EGFR). The prognostic significance of mutations in exons 19 and 21, together with serum levels of EGFR, amphiregulin (AR), and Transforming Growth Factor-alpha (TGF-α) are implicated in diagnosis and treatment. The aim of this study was to examine the relationship of EGFR mutations in selected exons with the expression of relevant ligands in sera samples of NSCLC patients. For this, a group of NSCLC patients (n=98) referred to the hospital for lung surgery with a mean age of 59±10.5 were enrolled (M/F: 75/23). Blood specimen was collected from each patient. Besides, formalin fixed paraffin embedded tissues were processed for DNA extraction. Gene mutations in exons 19 and 21 were detected by direct sequencing, following DNA amplification which was done by PCR (Polymerase Chain Reaction). Also, serum levels of EGFR, AR, and TGF-α were measured by ELISA. The results of our study show that EGFR mutations were present in 37% of Iranian NSCLC patients. The most frequently identified mutations were deletions in exon 19 (72.2%) and substitutions in exon 21 (27.8%). The most frequently identified alteration, which is considered as a rare mutation, was the E872K mutation in exon 21, which was found in 90% (9 out of 10) cases. EGFR mutation detected in exon 21 was significantly (P<0.05) correlated with the levels of its ligands, EGFR and TGF-α in serum samples. Furthermore, it was found that increased serum AR (>3pg/ml) and TGF-α (>10.5 pg/ml) were associated with shorter overall survival (P<0.05). The results clearly showed a close relationship between EGFR mutations and serum EGFR and serum TGF-α. Increased serum EGFR was associated with TGF-α and AR and linked to poor prognosis of NSCLC. These findings are implicated in clinical decision-making related to EGFR-Tyrosine kinase inhibitors (TKIs).

Keywords: lung cancer, Iranian patients, epidermal growth factor, mutation, prognosis

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Authors: Saif N. Al-Bahry, Yahya M. Al-Wahaibi, Abdulkadir E. Elshafie, Ali S. Al-Bemani, Sanket J. Joshi

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Environmental pollution is a global problem and best possible solution is identifying and utilizing native microorganisms. One possible application of microbial product -biosurfactant is in bioremediation of hydrocarbon contaminated sites. We have screened forty two different petroleum contaminated sites from Oman, for biosurfactant producing spore-forming bacterial isolates. Initial screening showed that out of 42 soil samples, three showed reduction in surface tension (ST) and interfacial tension (IFT) within 24h of incubation at 40°C. Out of those 3 soil samples, one was further selected for isolation of bacteria and 14 different bacteria were isolated in pure form. Of those 14 spore-forming, rod shaped bacteria, two showed highest reduction in ST and IFT in the range of 70mN/m to < 35mN/m and 26.69mN/m to < 9mN/m, respectively within 24h. These bacterial biosurfactants may be utilized for bioremediation of oil-spills.

Keywords: bioremediation, hydrocarbon pollution, spore-forming bacteria, bio-surfactant

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Authors: Ryan Dale B. Elnar

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This study developed a multidimensional need assessment scale for college students called The University of Mindanao Needs Assessment Scale (UMNAS). Although there are context-specific instruments measuring the needs of clinical and non-clinical samples, literature reveals no standardized scales to measure the needs of the college students thus a four-phase item development process was initiated to support its content validity. Comprising seven broad facets namely spiritual-moral, intrapersonal, socio-personal, psycho-emotional, cognitive, physical and sexual, a pyramid model of college needs was deconstructed through FGD sample to support the literature review. Using various construct validity procedures, the model was further tested using a total of 881 Filipino college samples. The result of the study revealed evidences of the reliability and validity of the UMNAS. The reliability indices range from .929-.933. Exploratory and confirmatory factor analyses revealed a one-factor-six-dimensional instrument to measure the needs of the college students. Using multivariate regression analysis, year level and course are found predictors of students’ needs. Content analysis attested the usefulness of the instrument to diagnose students’ personal and academic issues and concerns in conjunction with other measures. The norming process includes 1728 students from the different colleges of the University of Mindanao. Further validation is recommended to establish a national norm for the instrument.

Keywords: needs assessment scale, validity, factor analysis, college students

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Authors: Y. Kalachyova, O. Lyutakov, V. Svorcik

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One of the most significant obstacles for the application of surface enhanced Raman spectroscopy (SERS) is the poor reproducibility of SERS active substrates: SERS intensity can be varied from one substrate to another and moreover along the one substrate surface. High enhancement of the near-field intensity is the key factor for ultrasensitive SERS realization. SERS substrate can be prepared through introduction of highly ordered metal array, where light focusing is achieved through excitation of surface plasmon-polaritons (SPPs). In this work, we report the preparation of silver nanostructures with plasmon absorption peaks tuned by the metal arrangement. Excimer laser modification of poly(methyl methacrylate) followed by silver evaporation is proposed as an effective way for the creation of reproducible and effective surface plasmon-polaritons (SPP)-based SERS substrate. Theoretical and experimental studies were performed to optimize structure parameter for effective SPP excitation. It was found that the narrow range of grating periodicity and metal thickness exist, where SPPs can be most efficiently excited. In spite of the fact, that SERS response was almost always achieved, the enhancement factor was found to vary more with the effectivity of SPP excitation. When the real structure parameters were set to optimal for SPP excitation, a SERS enhancement factor was achieved up to four times. Theoretical and experimental investigation of SPP excitation on the two-dimensional periodical silver array was performed with the aim to make SERS response as high as possible.

Keywords: grating, nanostructures, plasmon-polaritons, SERS

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Authors: H. Hruschka

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This paper presents the first comparison of the performance of the restricted Boltzmann machine and the deep belief net on binary market basket data relative to binary factor analysis and the two best-known topic models, namely Dirichlet allocation and the correlated topic model. This comparison shows that the restricted Boltzmann machine and the deep belief net are superior to both binary factor analysis and topic models. Managerial implications that differ between the investigated models are treated as well. The restricted Boltzmann machine is defined as joint Boltzmann distribution of hidden variables and observed variables (purchases). It comprises one layer of observed variables and one layer of hidden variables. Note that variables of the same layer are not connected. The comparison also includes deep belief nets with three layers. The first layer is a restricted Boltzmann machine based on category purchases. Hidden variables of the first layer are used as input variables by the second-layer restricted Boltzmann machine which then generates second-layer hidden variables. Finally, in the third layer hidden variables are related to purchases. A public data set is analyzed which contains one month of real-world point-of-sale transactions in a typical local grocery outlet. It consists of 9,835 market baskets referring to 169 product categories. This data set is randomly split into two halves. One half is used for estimation, the other serves as holdout data. Each model is evaluated by the log likelihood for the holdout data. Performance of the topic models is disappointing as the holdout log likelihood of the correlated topic model – which is better than Dirichlet allocation - is lower by more than 25,000 compared to the best binary factor analysis model. On the other hand, binary factor analysis on its own is clearly surpassed by both the restricted Boltzmann machine and the deep belief net whose holdout log likelihoods are higher by more than 23,000. Overall, the deep belief net performs best. We also interpret hidden variables discovered by binary factor analysis, the restricted Boltzmann machine and the deep belief net. Hidden variables characterized by the product categories to which they are related differ strongly between these three models. To derive managerial implications we assess the effect of promoting each category on total basket size, i.e., the number of purchased product categories, due to each category's interdependence with all the other categories. The investigated models lead to very different implications as they disagree about which categories are associated with higher basket size increases due to a promotion. Of course, recommendations based on better performing models should be preferred. The impressive performance advantages of the restricted Boltzmann machine and the deep belief net suggest continuing research by appropriate extensions. To include predictors, especially marketing variables such as price, seems to be an obvious next step. It might also be feasible to take a more detailed perspective by considering purchases of brands instead of purchases of product categories.

Keywords: binary factor analysis, deep belief net, market basket analysis, restricted Boltzmann machine, topic models

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Authors: Abidullah, Basharat Hussain, Jong Seok Kim

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Polymer electrolyte membrane fuel cell (PEMFC) is an electrochemical cell, which undergoes an oxygen reduction reaction to produce electrical energy. Platinum (Pt) metal has been used as a catalyst since its inception, but expensiveness is the major obstacle in the commercialization of fuel cells. Herein a non-precious group metal (NPGM) is employed instead of Pt to reduce the cost of PEMFCs. Manganese dioxide impregnated carbon nanotubes (MnO₂-CNTs composite) is a catalyst having excellent electrochemical properties and offers a better alternative to the Platinum-based PEMFC. The catalyst is synthesized by impregnating the transition metal on large surface carbonaceous CNTs by hydrothermal synthesis techniques. To enhance the catalytic activity and increase the volumetric current density, the sample was pyrolyzed at 800ᵒC under a nitrogen atmosphere. During pyrolysis, the nitrogen was doped in the framework of CNTs. Then the material was treated with acid for removing the unreacted metals and adding oxygen functional group to the CNT framework. This process ameliorates the catalytic activity of the manganese-based catalyst. The catalyst has been characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and the catalyst activity has been examined by rotating disc electrode (RDE) experiment. The catalyst was strong enough to withstand an austere alkaline environment in experimental conditions and had a high electrocatalytic activity for oxygen reduction reaction (ORR). Linear Sweep Voltammetry (LSV) depicts an excellent current density of -4.0 mA/cm² and an overpotential of -0.3V vs. standard calomel electrode (SCE) in 0.1M KOH electrolyte. Rotating disk electrode (RDE) was conducted at 400, 800, 1200, and 1600 rpm. The catalyst exhibited a higher methanol tolerance and long term durability with respect to commercial Pt/C. The results for MnO₂-CNT show that the low-cost catalyst will supplant the expensive Pt/C catalyst in the fuel cell.

Keywords: carbon nanotubes, methanol fuel cell, oxygen reduction reaction, MnO₂-CNTs

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Authors: Hilary Rutto, Linda Sibali

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In these modern times, we constantly search for new and innovative technologies to lift the burden of our extreme energy demand. The overall purpose of biofuel production research is to source an alternative energy source to replace the normal use of fossil fuel as liquid petroleum products. This experiment looks at the basis of biodiesel production with regards to alternative catalysts that can be used to produce biodiesel. The key factors that will be addressed during the experiments will focus on temperature variation, catalyst additions to the overall reaction, methanol to oil ratio, and the impact of agitation on the reaction. Brine samples sources from nearby plants will be evaluated and tested thoroughly and the key characteristics of these brine samples analysed for the verification of its use as a possible catalyst in biodiesel production. The one factor at a time experimental approach was used in this experiment, and the recycle and reuse characteristics of the heterogeneous catalyst was evaluated.

Keywords: brine sludge, heterogenous catalyst, biodiesel, one factor

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Authors: M. Zain, Thaung H. Aung, Naveed Anwar

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During the service life, a structure may experience extreme loading conditions. The current study proposes a new methodology that covers the effect of uncertainty involved in gravity loadings on key structural elements of new and complex structures by emphasizing on a very realistic assumption that allows the 'Performance-Based Assessment' to be executed on the structure against the gravity loadings. The methodology does not require the complete removal of an element, instead, it permits the incremental reduction in the capacity of key structural elements and preserves the same stiffness of the member in each case of capacity loss. To demonstrate the application of the proposed methodology, a 13 story complex structure is selected that comprises of a diverse structural configuration. The results ensure the structural integrity against the applied gravity loadings, as well as the effectiveness of the proposed methodology.

Keywords: force-deformation relationship, gravity loading, incremental capacity reduction, multi-linear plastic link element, SAP2000, stiffness

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Authors: Xuan Zhao, Wen Jiang

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In this study, a web crawler was used to collect POI sample data from 38 districts and counties of Chongqing in 2022, and ArcGIS was combined to coordinate and projection conversion and realize data visualization. Nuclear density analysis and spatial correlation analysis were used to explore the spatial distribution characteristics of elderly care facilities in Chongqing, and K mean cluster analysis was carried out with GeoDa to study the spatial concentration degree of elderly care resources in 38 districts and counties. Finally, the driving force of spatial differentiation of elderly care facilities in various districts and counties of Chongqing is studied by using the method of geographic detector. The results show that: (1) in terms of spatial distribution structure, the distribution of elderly care facilities in Chongqing is unbalanced, showing a distribution pattern of ‘large dispersion and small agglomeration’ and the asymmetric pattern of ‘west dense and east sparse, north dense and south sparse’ is prominent. (2) In terms of the spatial matching between elderly care resources and the elderly population, there is a weak coordination between the input of elderly care resources and the distribution of the elderly population at the county level in Chongqing. (3) The analysis of the results of the geographical detector shows that the single factor influence is mainly the number of elderly population, public financial revenue and district and county GDP. The high single factor influence is mainly caused by the elderly population, public financial income, and district and county GDP. The influence of each influence factor on the spatial distribution of elderly care facilities is not simply superimposed but has a nonlinear enhancement effect or double factor enhancement. It is necessary to strengthen the synergistic effect of two factors and promote the synergistic effect of multiple factors.

Keywords: aging, elderly care facilities, spatial differentiation, geographical detector, driving force analysis, Mountain city

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Authors: R. N. Jay A. Ablog, M. N. Dyanne R. Del Carmen, Roma Rose A. Dela Cruz, Joselle Dara M. Estrada, Luke Clifferson M. Gagarin, Florence T. Lang-ay, Ma. Dayanara O. Mariñas, Maria Christina S. Nepa, Jahraine Chyle B. Ocampo, Mark Reynie Renz V. Silva, Jenny Lyn L. Soriano, Loreal Cloe M. Suva, Jackelyn R. Torres

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Background: To date, there is dearth of literature as to the effect of relaxation techniques in lowering the stress level of mothers of children with autism spectrum disorder (ASD). Aim: To investigate the effectiveness of 4-week relaxation techniques in stress level reduction of mothers of children with ASD. Methods: Quasi experimental design. It included 25 mothers (10-experimental, 15-control) who were chosen via purposive sampling. The mothers were recruited in the different SPED centers in Baguio City and La Trinidad and in the community. Statistics used were T-test and Related T-Test. Results: The overall weighted mean score after 4-week training is 2.3, indicating that the relaxation techniques introduced were moderately effective in lowering stress level. Statistical analysis (T-test; CV=4.51>TV=2.26) shown a significant difference in the stress level reduction of mothers in the experimental group pre and post interventions. There is also a significant difference in the stress level reduction in the control and the experimental group (Related T-test; CV=2.08 >TV=2.07). The relaxation techniques introduced were favorable, cost-effective, and easy to perform interventions to decrease stress level.

Keywords: relaxation techniques, mindful eating, progressive muscle relaxation, breathing exercise, autism spectrum disorder

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Authors: Yu-Ming Wang, Jia-Hong Jian

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The Internet and digital publication technologies have brought dramatic impacts on how people collect, organize, disseminate, access, store, and use information. More and more governments, schools, and organizations spent huge funds to develop digital libraries. A digital library can be regarded as a web extension of traditional physically libraries. People can search diverse publications, find out the position of knowledge resources, and borrow or buy publications through digital libraries. People can gain knowledge and students or employees can finish their reports by using digital libraries. Since the considerable funds and energy have been invested in implementing digital libraries, it is important to understand the evaluative criteria from the users’ viewpoint in order to enhance user acceptance. This study develops a list of user acceptance criteria for digital libraries. An initial criteria list was developed based on some previously validated instruments related to digital libraries. Data were collected from user experiences of digital libraries. The exploratory factor analysis and confirmatory factor analysis were adopted to purify the criteria list. The reliabilities and validities were tested. After validating the criteria list, a user survey was conducted to collect the comparative importance of criteria. The analytic hierarchy process (AHP) method was utilized to derive the importance of each criterion. The results of this study contribute to an e understanding of the criteria and relative importance that users evaluate for digital libraries.

Keywords: digital library, user acceptance, analytic hierarchy process, factor analysis

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Authors: Gui Yang Wu, Bo Wang, Xin Wang

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Nowadays, 5G service-based interface architecture uses text-based payload like JSON to transfer business data between network functions, which has obvious advantages as internet services but causes unnecessarily larger traffic. In this paper, a new 5G application payload size reduction method is presented to provides the mechanism to negotiate about new capability between network functions when network communication starts up and how 5G application data are reduced according to negotiated information with peer network function. Without losing the advantages of 5G text-based payload, this method demonstrates an excellent result on application payload size reduction and does not increase the usage quota of computing resource. Implementation of this method does not impact any standards or specifications and not change any encoding or decoding functionality too. In a real 5G network, this method will contribute to network efficiency and eventually save considerable computing resources.

Keywords: 5G, JSON, payload size, service-based interface

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Authors: Hyun Kyu Lee, Won Zin Oh, June Hyun Kim, Jin Hee Kim, Sang June Choi, Hak Soo Kim

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The oxidative dissolution of chromium oxide by manganese oxides including permanganate have been widely studied not only for the chemical decontamination of nuclear power plant, but also for the environmental control of the toxic chromate caused by naturally occurring manganese dioxide. However, little attention has been made for the spontaneous reductive decomposition of permanganate in the water, which is a competing reaction with the oxidation of the chromium oxide by permanganate. The objective of this study is to investigate the spontaneous reductive decomposition behavior of permanganate in the water, depending on the variation of acidity, temperature and concentration. Results of the experiments showed that the permanganate reductive decomposition product is manganese dioxide, and this reaction accompanies with the same molar amount of hydrogen ion consumption. Therefore, at the neutral condition (ex. potassium permanganate solution without acidic chemicals), the permanganate do not reduce by itself at any condition of temperature, concentration within the experimental range. From the results, we confirmed that the oxidation reaction for the permanganate reduction is the water oxidation that is accompanying the oxygen evolution. The experimental results on the reductive decomposition behavior of permanganate in the water also showed that the degree and rate of permanganate reduction increases with the temperature, acidity and concentration. The spontaneous decomposition of the permanganates obtained in the studies would become a good reference to select the operational condition, such as temperature, acidity and concentration, for the chemical decontamination of nuclear power plants.

Keywords: permanganate reduction, spontaneous decomposition, water oxidation, acidity, temperature, permanganate concentration, chemical decontamination, nuclear power plant

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Authors: Adedapo Jepson Olumide, Kurowska Ewa, K. Schoeneich, Ikpokonte A. Enoch

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In this paper, subsurface temperature measured from continuous temperature logs were used to determine the geothermal gradient of NigerDelta sedimentary basin. The measured temperatures were corrected to the true subsurface temperatures by applying the American Association of Petroleum Resources (AAPG) correction factor, borehole temperature correction factor with La Max’s correction factor and Zeta Utilities borehole correction factor. Geothermal gradient in this basin ranges from 1.20C to 7.560C/100m. Six geothermal anomalies centres were observed at depth in the southern parts of the Abakaliki anticlinorium around Onitsha, Ihiala, Umuaha area and named A1 to A6 while two more centre appeared at depth of 3500m and 4000m named A7 and A8 respectively. Anomaly A1 describes the southern end of the Abakaliki anticlinorium and extends southwards, anomaly A2 to A5 were found associated with a NW-SE structural alignment of the Calabar hinge line with structures describing the edge of the Niger Delta basin with the basement block of the Oban massif. Anomaly A6 locates in the south-eastern part of the basin offshore while A7 and A8 are located in the south western part of the basin offshore. At the average exploratory depth of 3500m, the geothermal gradient values for these anomalies A1, A2, A3, A4, A5, A6, A7, and A8 are 6.50C/100m, 1.750C/100m, 7.50C/100m, 1.250C/100m, 6.50C/100m, 5.50C/100m, 60C/100m, and 2.250C/100m respectively. Anomaly A8 area may yield higher thermal value at greater depth than 3500m. These results show that anomalies areas of A1, A3, A5, A6 and A7 are potentially prospective and explorable for geothermal energy using abandoned oil wells in the study area. Anomalies A1, A3.A5, A6 occur at areas where drilled boreholes were not exploitable for oil and gas but for the remaining areas where wells are so exploitable there appears no geothermal anomaly. Geothermal energy is environmentally friendly, clean and reversible.

Keywords: temperature logs, geothermal gradient anomalies, alternative energy, Niger delta basin

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Authors: Renato Santos Paulinelli Raposo, Vinicius Resende Domingues, Manoel Porfirio Cordao Neto

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Rapid drawdown is one of the cases referred to ground stability study in dam projects. Due to the complexity generated by the combination of loads and the difficulty in determining the parameters, analyses of rapid drawdown are usually performed considering the immediate reduction of water level upstream. The proposal of a simulation, considering the gradual reduction in water level upstream, requires knowledge of parameters about consolidation and those related to unsaturated soil. In this context, the purpose of this study is to understand the methodology of collection and analysis of parameters to simulate a rapid drawdown in dams. Using a numerical tool, the study is complemented with a hypothetical case study that can assist the practical use of data compiled. The referenced dam presents homogeneous section composed of clay soil, a height of 70 meters, a width of 12 meters, and upstream slope with inclination 1V:3H.

Keywords: dam, GeoStudio, rapid drawdown, stability analysis

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Authors: Chia-Ching Tsai, Ting-Hsiu Chen

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This paper adopted 2X2 factorial design. One factor was experimental versus control condition. The other factor was types of animated spokescharacter, and one of the two levels was expert type, and the other level is attractive type. In the study, we use control versus experimental conditioning and types of animated spokescharacter as independent variables, and brand attitude as dependent variable to examine the conditioning effect of types of animated spokescharacter on brand attitude. There are 123 subjects participating in the experiment. The results showed conditioning group presents that animated spokescharacter has significantly superior effect of product endorsement in contrast to non-conditioning one, while there is no significant impact of types of animated spokescharacter on brand attitude.

Keywords: classical conditioning, animated spokes-character, brand attitude, factorial design

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Authors: Michael Scott Evans, Andrew Smith

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The feeling of fatigue at work could potentially have devastating consequences. The aim of this study was to investigate whether the well-established objective indicator of fatigue – the Fatigue Risk Index (FRI) calculator used by the rail industry is an effective indicator to the number of safety incidents, in which fatigue could have been a contributing factor. The study received ethics approval from Cardiff University’s Ethics Committee (EC.16.06.14.4547). A total of 901 safety incidents were recorded from a single British rail franchise between 1st June 2010 – 31st December 2016, into the Safety Management Information System (SMIS). The safety incident types identified that fatigue could have been a contributing factor were: Signal Passed at Danger (SPAD), Train Protection & Warning System (TPWS) activation, Automatic Warning System (AWS) slow to cancel, failed to call, and station overrun. From the 901 recorded safety incidents, the scheduling system CrewPlan was used to extract the Fatigue Index (FI) score and Risk Index (RI) score of all train drivers on the day of the safety incident. Only the working rosters of 64.2% (N = 578) (550 men and 28 female) ranging in age from 24 – 65 years old (M = 47.13, SD = 7.30) were accessible for analyses. Analysis from all 578 train drivers who were involved in safety incidents revealed that 99.8% (N = 577) of Fatigue Index (FI) scores fell within or below the identified guideline threshold of 45 as well as 97.9% (N = 566) of Risk Index (RI) scores falling below the 1.6 threshold range. Their scores represent good practice within the rail industry. These findings seem to indicate that the current objective indicator, i.e. the FRI calculator used in this study by the British rail franchise was not an effective predictor of train driver’s FI scores and RI scores, as safety incidents in which fatigue could have been a contributing factor represented only 0.2% of FI scores and 2.1% of RI scores. Further research is needed to determine whether there are other contributing factors that could provide a better indication as to why there is such a significantly large proportion of train drivers who are involved in safety incidents, in which fatigue could have been a contributing factor have such low FI and RI scores.

Keywords: fatigue risk index calculator, objective indicator of fatigue, rail industry, safety incident

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Authors: Sunil Mittal, Sukhpreet Singh, Hardeep Kaur

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The affinity of thiol group with heavy metals is a well-established phenomenon. The present investigation has been focused on electrochemical response of cysteine and thioredoxin against arsenite (As III) on indium tin oxide (ITO) electrodes. It was observed that both the compounds produce distinct response in free and immobilised form at the electrode. The SEM, FTIR, and impedance studies of the modified electrode were conducted for characterization. Various parameters were optimized to achieve As (III) effect on the reduction potential of the compounds. Cyclic voltammetry and linear sweep voltammetry were employed as the analysis techniques. The optimum response was observed at neutral pH in both the cases, at optimum concentration of 2 mM and 4.27 µM for cysteine and thioredoxin respectively. It was observed that presence of As (III) increases the reduction current of both the moieties. The linear range of detection for As (III) with cysteine was from 1 to 10 mg L⁻¹ with detection limit of 0.8 mg L⁻¹. The thioredoxin was found more sensitive to As (III) and displayed a linear range from 0.1 to 1 mg L⁻¹ with detection limit of 10 µg L⁻¹.

Keywords: arsenite, cyclic voltammetry, cysteine, thioredoxin

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Authors: Majid Haghshenas, James Wilson, Ranganathan Kumar

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In this study, an Algebraic Coupled Level Set-Volume of Fluid (A-CLSVOF) method with capillary pressure treatment is proposed for the modeling of two-phase capillary flows. The Volume of Fluid (VOF) method is utilized to incorporate one-way coupling with the Level Set (LS) function in order to further improve the accuracy of the interface curvature calculation and resulting surface tension force. The capillary pressure is determined and treated independently of the hydrodynamic pressure in the momentum balance in order to maintain consistency between cell centered and interpolated values, resulting in a reduction in parasitic currents. In this method, both VOF and LS functions are transported where the new volume fraction determines the interface seed position used to reinitialize the LS field. The Hamilton-Godunov function is used with a second order (in space and time) discretization scheme to produce a signed distance function. The performance of the current methodology has been tested against some common test cases in order to assess the reduction in non-physical velocities and improvements in the interfacial pressure jump. The cases of a static drop, non-linear Rayleigh-Taylor instability and finally a droplets impact on a liquid pool were simulated to compare the performance of the present method to other well-known methods in the area of parasitic current reduction, interface location evolution and overall agreement with experimental results.

Keywords: two-phase flow, capillary flow, surface tension force, coupled LS with VOF

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Authors: Spandan Sahu, Amiya Kumar Pati, Kishanjit Kumar Khatua

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Vegetation plays a major role in deciding the flow parameters in an open channel. It enhances the aesthetic view of the revetments. The major types of vegetation in river typically comprises of herbs, grasses, weeds, trees, etc. The vegetation in an open channel usually consists of aquatic plants with complete submergence, partial submergence, floating plants. The presence of vegetative plants can have both benefits and problems. The major benefits of aquatic plants are they reduce the soil erosion, which provides the water with a free surface to move on without hindrance. The obvious problems are they retard the flow of water and reduce the hydraulic capacity of the channel. The degree to which the flow parameters are affected depends upon the density of the vegetation, degree of submergence, pattern of vegetation, vegetation species. Vegetation in open channel tends to provide resistance to flow, which in turn provides a background to study the varying trends in flow parameters having vegetative growth in the channel surface. In this paper, an experiment has been conducted on a meandering channel having sinuosity of 1.33 with rigid vegetation cover to investigate the effect on flow parameters, variation of manning’s n with degree of the denseness of vegetation, vegetation pattern and submergence criteria. The measurements have been carried out in four different cross-sections two on trough portion of the meanders, two on the crest portion. In this study, the analytical solution of Shiono and knight (SKM) for lateral distributions of depth-averaged velocity and bed shear stress have been taken into account. Dimensionless eddy viscosity and bed friction have been incorporated to modify the SKM to provide more accurate results. A mathematical model has been formulated to have a comparative analysis with the results obtained from Shiono-Knight Method.

Keywords: bed friction, depth averaged velocity, eddy viscosity, SKM

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Authors: Abdullah AlGhazali, Richard Fairchild, Yilmaz Guney

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We examine the effect of managerial overconfidence on UK firms’ payout policy for the period 2000 to 2012. The analysis incorporates, in addition to common firm-specific factors, a wide range of corporate governance factors and managerial characteristics that have been documented to affect the relationship between overconfidence and payout policy. Our results are robust to several estimation considerations. The findings show that the influence of overconfident CEOs on the amount of, and the propensity to pay, dividends is significant within the UK context. Specifically, we detect that there is a reduction in dividend payments in firms managed by overconfident managers compared to their non-overconfident counterparts. Moreover, we affirm that cash flows, firm size and profitability are positively correlated, while leverage, firm growth and investment are negatively correlated with the amount of and propensity to pay dividends. Interestingly, we demonstrate that firms with the potential for undervaluation reduce dividend payments. Some of the corporate governance factors are shown to motivate firms to pay more dividends while these factors seem to have no influence on the propensity to pay dividends. The results also show that in general higher overconfidence leads to more share repurchases but the lower total payout. Overall, managerial overconfidence should be considered as an important factor influencing payout policy in addition to other known factors.

Keywords: dividends, repurchases, UK firms, overconfidence, corporate governance, undervaluation

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Authors: Firas Mohamad Al-Sabek

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The Purpose of the paper is to examine the most critical and important factor which will affect the implementation of Total Quality Management (TQM) in the construction industry in the United Arab Emirates. It also examines the most effected Project outcome from implementing TQM. A framework was also proposed depending on the literature studies. The method used in this paper is a quantitative study. A survey with a sample of 60 respondents was created and distributed in a construction company in Abu Dhabi, which includes 15 questions to examine the most critical factor that will affect the implementation of TQM in addition to the most effected project outcome from implementing TQM. The survey showed that management commitment is the most important factor in implementing TQM in a construction company. Also it showed that Project cost is most effected outcome from the implementation of TQM. Management commitment is very important for implementing TQM in any company. If the management loose interest in quality then everyone in the organization will do so. The success of TQM will depend mostly on the top of the pyramid. Also cost is reduced and money is saved when the project team implement TQM. While if no quality measures are present within the team, the project will suffer a commercial failure. Based on literature, more factors can be examined and added to the model. In addition, more construction companies could be surveyed in order to obtain more accurate results. Also this study could be conducted outside the United Arab Emirates for further enchantment.

Keywords: construction project, total quality management, management commitment, cost, theoretical framework

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Authors: Mária Hudáková, Mária Lusková

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This report is focused on widening the theoretical knowledge as well as controlling practical application from the risk management point of view, regarding to dynamic business changes that have occurred in Slovakia which recently has been considered to be an environment full of risk and uncertainty. The idea of the report is the proposal of the controlling operation model in the course of risk management process in an enterprise operating in Slovakia, by which the controller is able to identify early risk factors in suggested major areas of the business management upon appropriate business information integration, consecutive control and prognoses and to prepare in time full-value documents in order to suggest measures for reduction thereof. Dealing with risk factors, that can quickly limit the growth potential of the enterprise, is an essential part of managerial activities on each level. This is the reason why mutual unofficial, ergo collegial cooperation of individual departments is necessary for controlling application from the business risk management point of view. An important part of the report is elaborated survey of the most important risk factors existing in major management areas of enterprises operating in Slovakia. The outcome of the performed survey is a catalogue of the most important enterprise risk factors. The catalogue serves for better understanding risk factors affecting the Slovak enterprises, their importance and evaluation.

Keywords: controlling, information, risks, risk factor, crisis

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Authors: Siti Rahmah Shamsuri, Eiichiro Matsubara, Shohei Shiomi

Abstract:

The 1D nanomaterial is far surpassed the 0D nanomaterial. It does not just offer most of the benefit of the 0D nanomaterial such as the large surface area, a great number of active site and an efficient interfacial charge transfer but also can assemble into free-standing and flexible electrode due to their high aspect ratio. Thus, it is essential to develop a simple and ease synthesis of this 1D nanomaterial for the practical application. Here, nickel nanowire/cellulose hybrid has been successfully fabricated via a simple liquid-phase method with the assist of the magnetic field. A finer nickel nanowire was heterogeneously nucleated on the surface of the cellulose fiber, which demonstrated the effect of the hydroxyl group on the cellulose structure. The result of the nickel nanowire size was found to vary from 66-114 nm. A detailed discussion on the mechanism of the nickel nanowire/ cellulose hybrid formation is also shown in this paper.

Keywords: cellulose nanofiber, liquid-phase reduction, metal nanowire, nano hybrid material

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Authors: Mohamed M. Ali, Adel Nofal, Amr Kandil, Mahmoud Agour

Abstract:

High phosphorus gray iron (HPGI) is used to connect the steel stub of an anode rod to a prebaked anode carbon block in the aluminium reduction cells. In this paper, a complete characterization for HPGI was done, includes studying the chemical composition of the HPGI collar, anodic voltage drop, collar temperature over 30 days anode life cycle, microstructure and mechanical properties. During anode life cycle, the carbon content in HPGI was lowed from 3.73 to 3.38%, and different changes in the anodic voltage drop at the stub- collar-anode connection were recorded. The collar temperature increases over the anode life cycle and reaches to 850°C in four weeks after anode changing. Significant changes in the HPGI microstructure were observed after 3 and 30 days from the anode changing. To simulate the actual operating conditions in the steel stub/collar/carbon anode connection, a bench-scale experimental set-up was designed and used for electrical resistance and resistivity respectively. The results showed the current HPGI properties needed to modify or producing new alloys with excellent electrical and mechanical properties. The steel stub and HPGI thermal expansion were measured and studied. Considerable permanent expansion was observed for the HPGI collar after the completion of the heating-cooling cycle.

Keywords: high phosphorus gray iron (HPGI), aluminium reduction cells, anodic voltage drop, microstructure, mechanical and electrical properties

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Authors: Ayman Othman, Tallat Ali

Abstract:

The successive increase of generated waste materials like glass has led to many environmental problems. Using crushed waste glass in hot mix asphalt paving has been though as an alternative to landfill disposal and recycling. This paper discusses the possibility of utilizing crushed waste glass, as a part of fine aggregate in hot mix asphalt in Egypt. This is done through evaluation of the mechanical properties of asphalt concrete mixtures mixed with waste glass and determining the appropriate glass content that can be adapted in asphalt pavement. Four asphalt concrete mixtures with various glass contents, namely; 0%, 4%, 8% and 12% by weight of total mixture were studied. Evaluation of the mechanical properties includes performing Marshall stability, indirect tensile strength, fracture energy and unconfined compressive strength tests. Laboratory testing had revealed the enhancement in both compressive strength and Marshall stability test parameters when the crushed glass was added to asphalt concrete mixtures. This enhancement was accompanied with a very slight reduction in both indirect tensile strength and fracture energy when glass content up to 8% was used. Adding more than 8% of glass causes a sharp reduction in both indirect tensile strength and fracture energy. Testing results had also shown a reduction in the optimum asphalt content when the waste glass was used. Measurements of the heat loss rate of asphalt concrete mixtures mixed with glass revealed their ability to hold heat longer than conventional mixtures. This can have useful application in asphalt paving during cold whether or when a long period of post-mix transportation is needed.

Keywords: waste glass, hot mix asphalt, mechanical performance, indirect tensile strength, fracture energy, compressive strength

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Authors: Zhang Shuqi, Liu Dan

Abstract:

For the problems in intelligent network anomaly traffic detection models, such as low detection accuracy caused by the lack of training samples, poor effect with small sample attack detection, a classification model enhancement method, F-ACGAN(Flow Auxiliary Classifier Generative Adversarial Network) which introduces generative adversarial network and adversarial training, is proposed to solve these problems. Generating adversarial data with category labels could enhance the training effect and improve classification accuracy and model robustness. FACGAN consists of three steps: feature preprocess, which includes data type conversion, dimensionality reduction and normalization, etc.; A generative adversarial network model with feature learning ability is designed, and the sample generation effect of the model is improved through adversarial iterations between generator and discriminator. The adversarial disturbance factor of the gradient direction of the classification model is added to improve the diversity and antagonism of generated data and to promote the model to learn from adversarial classification features. The experiment of constructing a classification model with the UNSW-NB15 dataset shows that with the enhancement of FACGAN on the basic model, the classification accuracy has improved by 8.09%, and the score of F1 has improved by 6.94%.

Keywords: data imbalance, GAN, ACGAN, anomaly detection, adversarial training, data augmentation

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Authors: Amessis-Ouchemoukh Nadia, Salhi Rim, Ouchemoukh Salim, Ayad Rabha, Sadou Dyhia, Guenaoui Nawel, Hamouche Sara, Madani Khodir

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The cooking method is a key factor influencing the quality of vegetables. In this study, the effect of the most common cooking methods on the nutritional composition, phenolic content, pigment content and antioxidant activities (evaluated by DPPH, ABTS, CUPRAC, FRAP, reducing power and phosphomolybdene method) of fresh, steamed, and boiled red beet was investigated. The fresh samples showed the highest nutritional and bioactive composition compared to the cooked ones. The boiling method didn’t lead to a significant reduction (p< 0.05) in the content of phenolics, flavonoids, flavanols and DPPH, ABTS, FRAP, CUPRAC, phosphomolybdeneum and reducing power capacities. This effect was less pronounced when steam cooking was used, and the losses of bioactive compounds were lower. As a result, steam cooking resulted in greater retention of bioactive compounds and antioxidant activity compared to boiling. Overall, this study suggests that steam cooking is a better method in terms of retention of pigments and bioactive compounds and antioxidant activity of beetroot.

Keywords: beta vulgaris, cooking methods, bioactive compounds, antioxidant activities

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Authors: Vinita Choudhary

Abstract:

The solidly mounted resonator (SMR) is a bulk acoustic wave-based device consisting of a piezoelectric layer sandwiched between two electrodes upon Bragg reflectors, which then are attached to a substrate. To transform the effective acoustic impedance of the substrate to a near zero value, the Bragg reflectors are composed of alternating high and low acoustic impedance layers of quarter-wavelength thickness. In this work presents the design and investigation of acoustic Bragg reflectors (ABRs) for solidly mounted bulk acoustic wave resonators through analysis and simulation. This performance of the resonator is analyzed using 1D Mason modeling. The performance parameters are the effect of Bragg pairs number on transmissivity, reflectivity, insertion loss, the electromechanical and quality factor of the 5GHz operating resonator.

Keywords: bragg reflectors, SMR, insertion loss, quality factor

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Authors: Avantika Verma

Abstract:

Diabetic retinopathy (DR) and Central serous retinopathy (CSR) are 2 distinct entities, with difference in age of presentation, eitiopathogenesis and clinical features, but when occurring together, can be a diagnostic dilemma and requires careful evaluation. Case study of 3 patients with long standing diabetes (>15yrs) and features of Central serous retinopathy was done at Bangalore West Lions Superspeciality Eye Hospital, Bangalore, India in 2013. Even though diabetic retinopathy and CSR have different pathologies, they can coexist. The reason for coexistence could be the following: A patient with CSR as a young adult could develop DR in later years. Stress could be the contributing factor in older patient with diabetes.Stress could be a common factor for both, as it is one of the important factors in the pathogenesis of Maturity Onset Diabetes Miletus (MODY). In any situation, a careful evaluation is necessary to differentiate the cause of fundus picture, as treatment differs for the two diseases.

Keywords: central serous retinopathy, diabetic retinopathy, existence, stress

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