Search results for: frequency and voltage regulation

Authors: Maria Viktoria Melgo

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This study aimed to determine the possible association between calcium intake and wealth indices of selected female adults. Specifically, it aimed to: a) determine the calcium intake adequacy of the respondents. b) determine the relationship, if any, between calcium intake adequacy, area and wealth indices. The study used the survey design and employed convenience sampling in selecting participants. Two hundred females aged 20 – 64 years old were covered in the study from depressed and non-depressed areas. Data collected were calcium intake taken from two 24-hour food recall and Food Frequency Questionnaire (FFQ) and wealth indices using housing characteristics, household assets and access to utilities and infrastructure. Descriptive statistics and Chi-square test were used to determine the frequency distribution and association between the given variables, respectively, using Statistical Package for Social Sciences (SPSS) and OpenEpi software. The results showed that there were 86% of respondents in the depressed area with an inadequate calcium intake while there were 78% of respondents in the non-depressed area with an adequate calcium intake. No significant relationship was obtained in most wealth indices with calcium intake adequacy and area but appliance and ownership of main material of the house showed a significant relationship to calcium intake adequacy by area. The study recommends that the Local Government Unit (LGU) should provide seminars or nutrition education that will further enhance the knowledge of the people in the community. The study also recommends to conduct a similar study but with different, larger sample size, different location nonetheless if it is in urban or rural and include the anthropometry measurement of the respondents.

Keywords: association, calcium intake adequacy, metro Manila, Philippines, wealth indices

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Authors: Xu Zhang

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This article unveils an indicator of language contact between English and Cantonese in one of the Outer Circle Englishes, Hong Kong (HK) English, through an empirical investigation into 1000 tokens from the Global Web-based English (GloWbE) corpus, employing frequency analysis and logistic regression analysis. It is perceived that Cantonese and general Chinese are contextually marked by an integral underlying thinking pattern. Chinese speakers exhibit a reliance on semantic context over syntactic rules and lexical forms. This linguistic trait carries over to their use of English, affording greater flexibility to formal elements in constructing English sentences. The study focuses on the syntactic positioning of the focusing subjunct ‘also’, a linguistic element used to add new or contrasting prominence to specific sentence constituents. The English language generally allows flexibility in the relative position of 'also’, while there is a preference for close marking relationships. This article shifts attention to Hong Kong, where Cantonese and English converge, and 'also' finds counterparts in Cantonese ‘jaa’ and Mandarin ‘ye’. Employing a corpus-based data-driven method, we investigate the syntactic position of 'also' in both HK and GB English. The study aims to ascertain whether HK English exhibits a greater 'syntactic freedom,' allowing for a more distant marking relationship with 'also' compared to GB English. The analysis involves a random extraction of 500 samples from both HK and GB English from the GloWbE corpus, forming a dataset (N=1000). Exclusions are made for cases where 'also' functions as an additive conjunct or serves as a copulative adverb, as well as sentences lacking sufficient indication that 'also' functions as a focusing particle. The final dataset comprises 820 tokens, with 416 for GB and 404 for HK, annotated according to the focused constituent and the relative position of ‘also’. Frequency analysis reveals significant differences in the relative position of 'also' and marking relationships between HK and GB English. Regression analysis indicates a preference in HK English for a distant marking relationship between 'also' and its focused constituent. Notably, the subject and other constituents emerge as significant predictors of a distant position for 'also.' Together, these findings underscore the nuanced linguistic dynamics in HK English and contribute to our understanding of language contact. It suggests that future pedagogical practice should consider incorporating the syntactic variation within English varieties, facilitating leaners’ effective communication in diverse English-speaking environments and enhancing their intercultural communication competence.

Keywords: also, Cantonese, English, focus marker, frequency analysis, language contact, logistic regression analysis

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Authors: Jayahar Sivasubramanian

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Understanding laminar-turbulent transition process in hyper-sonic boundary layers is crucial for designing viable high speed flight vehicles. The study of transition becomes particularly important in the high speed regime due to the effect of transition on aerodynamic performance and heat transfer. However, even after many years of research, the transition process in hyper-sonic boundary layers is still not understood. This lack of understanding of the physics of the transition process is a major impediment to the development of reliable transition prediction methods. Towards this end, spatial Direct Numerical Simulations are conducted to investigate the instability waves generated by a localized disturbance in a hyper-sonic flat plate boundary layer. In order to model a natural transition scenario, the boundary layer was forced by a short duration (localized) pulse through a hole on the surface of the flat plate. The pulse disturbance developed into a three-dimensional instability wave packet which consisted of a wide range of disturbance frequencies and wave numbers. First, the linear development of the wave packet was studied by forcing the flow with low amplitude (0.001% of the free-stream velocity). The dominant waves within the resulting wave packet were identified as two-dimensional second mode disturbance waves. Hence the wall-pressure disturbance spectrum exhibited a maximum at the span wise mode number k = 0. The spectrum broadened in downstream direction and the lower frequency first mode oblique waves were also identified in the spectrum. However, the peak amplitude remained at k = 0 which shifted to lower frequencies in the downstream direction. In order to investigate the nonlinear transition regime, the flow was forced with a higher amplitude disturbance (5% of the free-stream velocity). The developing wave packet grows linearly at first before reaching the nonlinear regime. The wall pressure disturbance spectrum confirmed that the wave packet developed linearly at first. The response of the flow to the high amplitude pulse disturbance indicated the presence of a fundamental resonance mechanism. Lower amplitude secondary peaks were also identified in the disturbance wave spectrum at approximately half the frequency of the high amplitude frequency band, which would be an indication of a sub-harmonic resonance mechanism. The disturbance spectrum indicates, however, that fundamental resonance is much stronger than sub-harmonic resonance.

Keywords: boundary layer, DNS, hyper sonic flow, instability waves, wave packet

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Authors: Mehdi Ameur, Ahmed Essadki, Tamou Nasser

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The purpose of this paper is the evaluation of photovoltaic system with MPPT techniques. This system is developed by combining the models of established solar module and DC-DC converter with the algorithms of perturbing and observing (P&O), incremental conductance (INC) and fuzzy logic controller (FLC). The system is simulated under different climate conditions and MPPT algorithms to determine the influence of these conditions on characteristic power-voltage of PV system. According to the comparisons of the simulation results, the photovoltaic system can extract the maximum power with precision and rapidity using the MPPT algorithms discussed in this paper.

Keywords: fuzzy logic controller, FLC, hill climbing, HC, incremental conductance (INC), perturb and observe (P&O), maximum power point, MPP, maximum power point tracking, MPPT

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Authors: E. Carraro, Sa. Bonetta, Si. Bonetta, E. Ceretti, G. C. V. Viola, C. Pignata, S. Levorato, T. Salvatori, S. Vannini, V. Romanazzi, A. Carducci, G. Donzelli, T. Schilirò, A. De Donno, T. Grassi, S. Bonizzoni, A. Bonetti, G. Gilli, U. Gelatti

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In 2013, air pollution and particulate matter were classified as carcinogenic to human by the IARC. At present, PM is Europe's most problematic pollutant in terms of harm to health, as reported by European Environmental Agency (EEA) in the EEA Technical Report on Air quality in Europe, 2015. A percentage between 17-30 of the EU urban population lives in areas where the EU air quality 24-hour limit value for PM10 is exceeded. Many studies have found a consistent association between exposure to PM and the incidence and mortality for some chronic diseases (i.e. lung cancer, cardiovascular diseases). Among the mechanisms responsible for these adverse effects, genotoxic damage is of particular concern. Children are a high-risk group in terms of the health effects of air pollution and early exposure during childhood can increase the risk of developing chronic diseases in adulthood. The MAPEC_LIFE (Monitoring Air Pollution Effects on Children for supporting public health policy) is a project founded by EU Life+ Programme (LIFE12 ENV/IT/000614) which intends to evaluate the associations between air pollution and early biological effects in children and to propose a model for estimating the global risk of early biological effects due to air pollutants and other factors in children. This work is focused on the micronuclei frequency in child buccal cells in association with airborne PM levels taking into account the influence of other factors associated with the lifestyle of children. The micronucleus test was performed in exfoliated buccal cells of 6–8 years old children from 5 Italian towns with different air pollution levels. Data on air quality during the study period were obtained from the Regional Agency for Environmental Protection. A questionnaire administered to children’s parents was used to obtain details on family socio-economic status, children health condition, exposures to other indoor and outdoor pollutants (i.e. passive smoke) and life-style, with particular reference to eating habits. During the first sampling campaign (winter 2014-15) 1315 children were recruited and sampled for Micronuclei test in buccal cells. In the sampling period the levels of the main pollutants and PM10 were, as expected, higher in the North of Italy (PM10 mean values 62 μg/m3 in Torino and 40 μg/m3 in Brescia) than in the other towns (Pisa, Perugia, Lecce). A higher Micronucleus frequency in buccal cells of children was found in Brescia (0.6/1000 cells) than in the other towns (range 0.3-0.5/1000 cells). The statistical analysis underlines a relation of the micronuclei frequency with PM concentrations, traffic level near child residence, and level of education of parents. The results suggest that, in addition to air pollution exposure, some other factors, related to lifestyle or further exposures, may influence micronucleus frequency and cellular response to air pollutants.

Keywords: air pollution, buccal cells, children, micronucleus cytome assay

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Authors: C. Benoudjafer, M. N. Tandjaoui, C. Benachaiba

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The use of kinetic energy of the wind is in full rise in the world and it starts to be known in our country but timidly. One or more aero generators can be installed to produce for example electricity on isolated places or not connected to the electrical supply network. To use the wind as energy source, it is necessary to know first the energy needs for the population and study the wind intensity, speed, frequency and direction.

Keywords: Algeria, renewable energies, wind, wind power, aero-generators, wind energetic potential

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Authors: Shimaa M. Elsaeed, Reem K. Farag, Ibrahim M. Nassar

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Hydrogel conductive polymer nanocomposite fabricated via in-situ polymerization of polyaniline (PANI) inside thermosensitive hydrogels based on hydroxy ethyl meth acrylate (HEMA) copolymer with 2-acrylamido-2-methyl propane sulfonic acid (AMPS). SEM micrographs show the nanometric size of the conductive material (polyaniline, PANI) dispersed in the hydrogel matrix. The swelling parameters of hydrogel are measured. The incorporation of PANI improves the mechanical properties and swelling up to 30,000% without breaking. X-ray diffraction shows that typical polyaniline crystallization is formed in composite, which is advantageous to increase the electrical conductivity of the composite hydrogel. Open-circuit voltage (I-V) curve fill factor of the highest photo-conversion efficiency and enhanced to use in solar cell.

Keywords: hydrogel, solar cell, conductive polymer, nanocomposite

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Authors: Takeshi Takemoto, Naoya Suzuki, Naohisa Takagaki, Satoru Komori, Masako Terui, George Truscott

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Drag coefficient is an important parameter in order to correctly estimate the air-sea momentum flux. However, The parameterization of the drag coefficient hasn’t been established due to the variation in the field data. Instead, a number of drag coefficient model formulae have been proposed, even though almost all these models haven’t discussed the extreme wind speed range. With regards to such models, it is unclear how the drag coefficient changes in the extreme wind speed range as the wind speed increased. In this study, we investigated the effect of the drag coefficient models concerning the air-sea momentum flux in the extreme wind range on a global scale, comparing two different drag coefficient models. Interestingly, one model didn’t discuss the extreme wind speed range while the other model considered it. We found that the difference of the models in the annual global air-sea momentum flux was small because the occurrence frequency of strong wind was approximately 1% with a wind speed of 20m/s or more. However, we also discovered that the difference of the models was shown in the middle latitude where the annual mean air-sea momentum flux was large and the occurrence frequency of strong wind was high. In addition, the estimated data showed that the difference of the models in the drag coefficient was large in the extreme wind speed range and that the largest difference became 23% with a wind speed of 35m/s or more. These results clearly show that the difference of the two models concerning the drag coefficient has a significant impact on the estimation of a regional air-sea momentum flux in an extreme wind speed range such as that seen in a tropical cyclone environment. Furthermore, we estimated each air-sea momentum flux using several kinds of drag coefficient models. We will also provide data from an observation tower and result from CFD (Computational Fluid Dynamics) concerning the influence of wind flow at and around the place.

Keywords: air-sea interaction, drag coefficient, air-sea momentum flux, CFD (Computational Fluid Dynamics)

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Authors: Mina Naeini, Thomas A. Adams II

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Solid Oxide Fuel Cells (SOFCs) feature high electrical efficiency and generate substantial amounts of waste heat that make them suitable for integrated community energy systems (ICEs). By harvesting and distributing the waste heat through hot water pipelines, SOFCs can meet thermal demand of the communities. Therefore, they can replace traditional gas boilers and reduce greenhouse gas (GHG) emissions. Despite these advantages of SOFCs over competing power generation units, this technology has not been successfully commercialized in large-scale to replace traditional generators in ICEs. One reason is that SOFC performance deteriorates over long-term operation, which makes it difficult to find the proper sizing of the cells for a particular ICE system. In order to find the optimal sizing and operating conditions of SOFCs in a community, a proper knowledge of degradation mechanisms and effects of operating conditions on SOFCs long-time performance is required. The simplified SOFC models that exist in the current literature usually do not provide realistic results since they usually underestimate rate of performance drop by making too many assumptions or generalizations. In addition, some of these models have been obtained from experimental data by curve-fitting methods. Although these models are valid for the range of operating conditions in which experiments were conducted, they cannot be generalized to other conditions and so have limited use for most ICEs. In the present study, a general, detailed degradation-based model is proposed that predicts the performance of conventional SOFCs over a long period of time at different operating conditions. Conventional SOFCs are composed of Yttria Stabilized Zirconia (YSZ) as electrolyte, Ni-cermet anodes, and LaSr₁₋ₓMnₓO₃ (LSM) cathodes. The following degradation processes are considered in this model: oxidation and coarsening of nickel particles in the Ni-cermet anodes, changes in the pore radius in anode, electrolyte, and anode electrical conductivity degradation, and sulfur poisoning of the anode compartment. This model helps decision makers discover the optimal sizing and operation of the cells for a stable, efficient performance with the fewest assumptions. It is suitable for a wide variety of applications. Sulfur contamination of the anode compartment is an important cause of performance drop in cells supplied with hydrocarbon-based fuel sources. H₂S, which is often added to hydrocarbon fuels as an odorant, can diminish catalytic behavior of Ni-based anodes by lowering their electrochemical activity and hydrocarbon conversion properties. Therefore, the existing models in the literature for H₂-supplied SOFCs cannot be applied to hydrocarbon-fueled SOFCs as they only account for the electrochemical activity reduction. A regression model is developed in the current work for sulfur contamination of the SOFCs fed with hydrocarbon fuel sources. The model is developed as a function of current density and H₂S concentration in the fuel. To the best of authors' knowledge, it is the first model that accounts for impact of current density on sulfur poisoning of cells supplied with hydrocarbon-based fuels. Proposed model has wide validity over a range of parameters and is consistent across multiple studies by different independent groups. Simulations using the degradation-based model illustrated that SOFCs voltage drops significantly in the first 1500 hours of operation. After that, cells exhibit a slower degradation rate. The present analysis allowed us to discover the reason for various degradation rate values reported in literature for conventional SOFCs. In fact, the reason why literature reports very different degradation rates, is that literature is inconsistent in definition of how degradation rate is calculated. In the literature, the degradation rate has been calculated as the slope of voltage versus time plot with the unit of voltage drop percentage per 1000 hours operation. Due to the nonlinear profile of voltage over time, degradation rate magnitude depends on the magnitude of time steps selected to calculate the curve's slope. To avoid this issue, instantaneous rate of performance drop is used in the present work. According to a sensitivity analysis, the current density has the highest impact on degradation rate compared to other operating factors, while temperature and hydrogen partial pressure affect SOFCs performance less. The findings demonstrated that a cell running at lower current density performs better in long-term in terms of total average energy delivered per year, even though initially it generates less power than if it had a higher current density. This is because of the dominant and devastating impact of large current densities on the long-term performance of SOFCs, as explained by the model.

Keywords: degradation rate, long-term performance, optimal operation, solid oxide fuel cells, SOFCs

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Authors: Alina Parincu, Giuseppe Empoli, Alexandru Capatina

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The purpose of this paper is to identify the most influential predictors of emotional intelligence skills, in the case of 20 business innovation coaches, on the co-creation of knowledge through coaching services delivered to innovative start-ups from Europe, funded through Horizon 2020 – SME Instrument. We considered the emotional intelligence skills (self-awareness, self-regulation, motivation, empathy and social skills) as antecedent conditions of the outcome: the quality of coaching services, perceived by the entrepreneurs who received funding within SME instrument, using fuzzy-sets qualitative comparative analysis (fsQCA) approach. The findings reveal that emotional intelligence skills, trained with neuro-management techniques, were associated with increased goal-focused business coaching skills.

Keywords: neuro-management, innovative start-ups, business coaching, fsQCA

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Authors: Bing Yan

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Nanomaterials are widely used in various industrial sectors, biomedicine, and more than 1300 consumer products. Although there is still no standard safety regulation, their potential toxicity is a major concern worldwide. We discovered that nanoparticles target and enter human cells1, perturb cellular signaling pathways2, affect various cell functions3, and cause malfunctions in animals4,5. Because the majority of atoms in nanoparticles are on the surface, chemistry modification on their surface may change their biological properties significantly. We modified nanoparticle surface using nano-combinatorial chemistry library approach6. Novel nanoparticles were discovered to exhibit significantly reduced toxicity6,7, enhance cancer targeting ability8, or re-program cellular signaling machineries7. Using computational chemistry, quantitative nanostructure-activity relationship (QNAR) is established and predictive models have been built to predict biocompatible nanoparticles.

Keywords: nanoparticle, nanotoxicity, nano-bio, nano-combinatorial chemistry, nanoparticle library

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Authors: A. N. Moulai Khatir

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SOI-Multifin-FETs are placed to be the workhorse of the industry for the coming few generations, and thus, in a few years because their excellent transistor characteristics, ideal sub-threshold swing, low drain induced barrier lowering (DIBL) without pocket implantation, and negligible body bias dependency. The corner effect may also exist in the two lower corners; this effect is called the BOX effect, which can also occur in the direction X-Z. The electric field lines from the source and drain cross the bottom oxide and arrive in the silicon. This effect is also called DIVSB (Drain Induced Virtual Substrate Basing). The potential in the silicon film in particular near the drain is increased by the drain bias. It is similar to DIBL and result in a decrease of the threshold voltage. This work provides an understanding of the limitation of this effect by reducing the fin width for components with increased fin number.

Keywords: SOI, finFET, corner effect, dual-gate, tri-gate, BOX, multi-finFET

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Authors: Min Chen, Rubi Gupta

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Understanding and predicting stock market movements is a challenging problem. It is believed stock markets are partially driven by public sentiments, which leads to numerous research efforts to predict stock market trend using public sentiments expressed on social media such as Twitter but with limited success. Recently a microblogging website StockTwits is becoming increasingly popular for users to share their discussions and sentiments about stocks and financial market. In this project, we analyze the text content of StockTwits tweets and extract financial sentiment using text featurization and machine learning algorithms. StockTwits tweets are first pre-processed using techniques including stopword removal, special character removal, and case normalization to remove noise. Features are extracted from these preprocessed tweets through text featurization process using bags of words, N-gram models, TF-IDF (term frequency-inverse document frequency), and latent semantic analysis. Machine learning models are then trained to classify the tweets' sentiment as positive (bullish) or negative (bearish). The correlation between the aggregated daily sentiment and daily stock price movement is then investigated using Pearson’s correlation coefficient. Finally, the sentiment information is applied together with time series stock data to predict stock price movement. The experiments on five companies (Apple, Amazon, General Electric, Microsoft, and Target) in a duration of nine months demonstrate the effectiveness of our study in improving the prediction accuracy.

Keywords: machine learning, sentiment analysis, stock price prediction, tweet processing

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Authors: Zhao Haoyue

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Due to the combined effects of climate change, urban expansion, and population growth, various environmental issues, such as urban heat islands and pollution, arise. Therefore, reliable information on urban environmental climate is needed to address and mitigate the negative effects. The emergence of urban climate maps provides a practical basis for urban climate regulation and improvement. This article takes Shapingba District, Chongqing City, as an example to study the construction method of urban thermal environment climate maps based on GIS spatial analysis technology. The thermal load, ventilation potential analysis map, and thermal environment comprehensive analysis map were obtained. Based on the classification criteria obtained from the climate map, corresponding protection and planning mitigation measures have been proposed.

Keywords: urban climate, GIS, heat island analysis, urban thermal environment

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Authors: Tamriko Pavliashvili

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Marriage is such an important institution of family law, which is an indicator of the development of society. Although a family can be created by the birth of a child between an unmarried couple, marriage is still the main basis for the creation of a family, during which the rights and duties imposed require legal regulation. At present, in the conditions of globalization, there are different types of marriage, although in the main countries, it is still a union of a woman and a man, which involves voluntary cohabitation and assuming and fulfilling the norms and responsibilities established on the basis of the law. Modern society is at the stage where there is a need to create a family, and therefore marriage provides the best opportunity for relationships and existence between people. The mentioned paper about the state institution - marriage gives us the opportunity to get more information about the existing habits, legal norms from the ancient times to the modern period in Georgia, and also through comparison we will see what the differences and commonalities were and are in the marriage law of the countries of the world and Georgia.

Keywords: marriage, family law, the union of man and woman, church law

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Authors: Yo Fukutani, Shuji Moriguchi, Takuma Kotani, Terada Kenjiro

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If risk management of the assets owned by companies, risk assessment of real estate portfolio, and risk identification of the entire region are to be implemented, it is necessary to consider simultaneous damage to multiple buildings. In this research, the Sagami Trough earthquake tsunami that could have a significant effect on the Japanese capital region is focused on, and a method is proposed for simultaneous damage assessment using copulas that can take into consideration the correlation of tsunami depths and building damage between two sites. First, the tsunami inundation depths at two sites were simulated by using a nonlinear long-wave equation. The tsunamis were simulated by varying the slip amount (five cases) and the depths (five cases) for each of 10 sources of the Sagami Trough. For each source, the frequency distributions of the tsunami inundation depth were evaluated by using the response surface method. Then, Monte-Carlo simulation was conducted, and frequency distributions of tsunami inundation depth were evaluated at the target sites for all sources of the Sagami Trough. These are marginal distributions. Kendall’s tau for the tsunami inundation simulation at two sites was 0.83. Based on this value, the Gaussian copula, t-copula, Clayton copula, and Gumbel copula (n = 10,000) were generated. Then, the simultaneous distributions of the damage rate were evaluated using the marginal distributions and the copulas. For the correlation of the tsunami inundation depth at the two sites, the expected value hardly changed compared with the case of no correlation, but the damage rate of the ninety-ninth percentile value was approximately 2%, and the maximum value was approximately 6% when using the Gumbel copula.

Keywords: copulas, Monte-Carlo simulation, probabilistic risk assessment, tsunamis

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Authors: Rob Waddle

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We study an economy with weak justice and security systems and with weak public policy and regulation or little capacity to implement them, and with high barriers to profitable sectors. We look at growth and development opportunities based on the derived demand. We show that there is hope for such an economy to grow up and to generate a win-win situation for all stakeholders if the derived demand is supplied. We then investigate conditions that could stimulate the derived demand supply. We show that little knowledge of public, private and international expenditures in the economy and academic tools are enough to trigger the derived demand supply. Our model can serve as guidance to donor and NGO working in developing countries, and show to media the best way to help is to share information about existing and accessible opportunities. It can also provide direction to vocational schools and universities that could focus more on providing tools to seize existing opportunities.

Keywords: growth, development, monopoly, oligopoly, inequality

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Authors: M. Suresh Kumar, K. Ramani

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This paper proposed the Multi-Carrier Pulse Width Modulation for the minimization of Total Harmonic Distortion in Cascaded H-Bridge Multi-Level Inverter. Multicarrier Pulse Width Modulation method uses Alternate Position of Disposition scheme to determine the appropriate switching angle to Multi-Level Inverter. In this paper simulation results shows that the validation of Multi-Carrier Pulse Width Modulation method does capably eliminate a great number of precise harmonics and minimize the Total Harmonic Distortion value in output voltage waveform.

Keywords: alternate position, fast fourier analysis, multi-carrier pulse width modulation, multi-level inverter, total harmonic distortion

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Authors: Kakali Bhadra

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Harmalol administration caused remarkable reduction in proliferation of HepG₂ cells with GI₅₀ of 14.2 mM, without showing much cytotoxicity in embryonic liver cell line, WRL-68. Data from circular dichroism and differential scanning calorimetric analysis of harmalol-CT DNA complex shows conformational changes with prominent CD perturbation and stabilization of CT DNA by 8 ^oC. Binding constant and stoichiometry was also calculated using the above biophysical techniques. Further, dose dependent apoptotic induction ability of harmalol was studied in HepG₂ cells using different biochemical assays. Generation of ROS, DNA damage, changes in cellular external and ultramorphology, alteration of membrane, formation of comet tail, decreased mitochondrial membrane potential and a significant increase in Sub G_o/G₁ population made the cancer cell, HepG₂, prone to apoptosis. Up regulation of p53 and caspase 3 further indicated the apoptotic role of harmalol.

Keywords: apoptosis, beta carboline alkaloid, comet assay, cytotoxicity, ROS

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Authors: Maatouk Mohamed, Nouira Mariem

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Background and aims: Healthcare-associated infections (HAI) represent a major public health problem worldwide. They represent one of the most serious adverse events in health care. The objectives of our study were to estimate the prevalence of HAI at the Charles Nicolle Hospital (CNH) and to identify the main associated factors as well as to estimate the frequency of antibiotic use. Methods: It was a cross sectional study at the CNH with a unique passage per department (OctoberDecember 2018). All patients present at the wards for more than 48 hours were included. All patients from outpatient consultations, emergency and dialysis departments were not included. The site definitions of infections proposed by the Centers for Disease Control and Prevention (CDC) were used. Only clinically and/or microbiologically confirmed active HAIs were included. Results: A total of 318 patients were included with a mean age of 52 years and a sex ratio (Female/Male) of 1.05. A total of 41 patients had one or more active HAIs, corresponding to a prevalence of 13.1% (95% CI: 9.3%-16.9%). The most frequent sites infections were urinary tract infections and pneumonia. Multivariate analysis among adult patients (>=18 years) (n=261), revealed that infection on admission (p=0.01), alcoholism (p=0.01), high blood pressure (p=0.008), having at least one invasive device inserted (p=0.004), and history of recent surgery (p=0.03), increased significantly the risk of HAIs. More than 1 of 3 patients (35.4%) were under antibiotics on the day of the survey, of which more than half (57.4%) were under 2 or more types of antibiotics. Conclusion: The prevalence of HAIs and antibiotic prescriptions at the CNH were considerably high. An infection prevention and control committee, as well as the development of an Antibiotic stewardship program with continuous monitoring using repeated prevalence surveys must be implemented to limit the frequency of these infections effectively.

Keywords: tumors, oesophagectomy, esophagogastric junction, systematic review

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Authors: Waleed Mandour

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This study presents multidimensional scrutiny of Benson et al.’s seven-category taxonomy of lexical collocations used by Egyptian medical authors and their peers of native-English speakers. It investigates 212 medical papers, all published during a span of 6 years (from 2013 to 2018). The comparison is held to the medical research articles submitted by native speakers of English (25,238 articles in total with over 103 million words) as derived from the Directory of Open Access Journals (a 2.7 billion-word corpus). The non-native speakers compiled corpus was properly annotated and marked-up manually by the researcher according to the standards of Weisser. In terms of statistical comparisons, though, deployed were the conventional frequency-based analysis besides the relevant criteria, such as association measures (AMs) in which LogDice is deployed as per the recommendation of Kilgariff et al. when comparing large corpora. Despite the terminological convergence in the subject corpora, comparison results confirm the previous literature of which the non-native speakers’ compositions reveal limited ranges of lexical collocations in terms of their distribution. However, there is a ubiquitous tendency of overusing the NS-high-frequency multi-words in all lexical categories investigated. Furthermore, Egyptian authors, conversely to their English-speaking peers, tend to embrace more collocations denoting quantitative rather than qualitative analyses in their produced papers. This empirical work, per se, contributes to the English for Academic Purposes (EAP) and English as a Lingua Franca in Academic settings (ELFA). In addition, there are pedagogical implications that would promote a better quality of medical research papers published in Egyptian universities.

Keywords: corpus linguistics, EAP, ELFA, lexical collocations, medical discourse

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Authors: Shiuh-Kuang Yang, Sheam-Chyun Lin, Jyin-Wen Cheng, Deng-Guei Hsu

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The torsional mode of guided wave, T(0,1), has been applied to detect characteristics and defects in pipelines, especially in the cases of coated, elevated and buried pipes. The signals of minor corrosions would be covered by the noise, unfortunately, because the coated material and buried medium always induce a strong attenuation of the guided wave. Furthermore, the guided wave would be attenuated more seriously and make the signals hard to be identified when setting the array ring of the transducers on a general corrosion area of the pipe. The objective of this study is then to discuss the effects of the above-mentioned general corrosion on guided wave tests by experiments and signal processing techniques, based on the use of the finite element method, the two-dimensional Fourier transform and the continuous wavelet transform. Results show that the excitation energy would be reduced when the array ring set on the pipe surface having general corrosion. The non-uniformed contact surface also produces the unwanted asymmetric modes of the propagating guided wave. Some of them are even mixing together with T(0,1) mode and increase the difficulty of measurements, especially when a defect or local corrosion merged in the general corrosion area. It is also showed that the guided waves attenuation are increasing with the increasing corrosion depth or the rising inspection frequency. However, the coherent signals caused by the general corrosion would be decayed with increasing frequency. The results obtained from this research should be able to provide detectors to understand the impact when the array ring set on the area of general corrosion and the way to distinguish the localized corrosion which is inside the area of general corrosion.

Keywords: guided wave, finite element method, two-dimensional fourier transform, wavelet transform, general corrosion, localized corrosion

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Authors: Agumah N. B. Orji, M. U., Oru C. M., Ugbo, E. N., Onwuliri E. A Nwakaeze, E. A.,

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ERG11 gene has been reported to be one of the genes whose expression is responsible for resistance of Candida to various triazole drugs, which are first line treatment for candidiasis. This study was carried out to determine the prevalence of Triazole (Fluconazole and voriconazole) resistant Candida albicans expressing ERG11 gene from adult females in Abakaliki. Urine and vaginal swab samples were randomly collected from volunteers after obtaining their consent to participate in the study. A total of 565 adult females participated in the study. A total of 340 urine specimens and 288 vaginal swab specimens were collected. Direct wet mount technique, as well as culture in Trichomonas broth, were used to examine the urine and vaginal swab specimens for the presence of motile Trichomonads. The Trichomonas broth used was selective for both T. vaginalis and C. albicans. Broths that yielded budding yeast cells after microscopy were subcultured on to Sabouraud dextrose agar, after which Germ tube test was carried out to confirm the presence of C. albicans. Biochemical tests, including carbohydrate fermentation and urease utilization, were also performed. Antibiogram of C. albicans isolates obtained from this study was carried out using commercially available azole drugs. Fluconazole and voriconazole were selected as Triazole drugs used for this study. Nystatin was used as a tangential control. An MIC test was carried out with E-strips on some of the resistant C. albicans isolates A total of 6 isolates that resisted all the azole drugs were selected and screened for the presence of ERG11 gene using Reverse transcriptase polymerase chain reaction technique. The total prevalence recorded for C. albicans was 13.0%. Frequency was statistically higher in Pregnant (7.96%) than non pregnant (5.09%) volunteers (X2=0.94 at P=0.05). With respect to clinical samples, frequency was higher in vaginal swabs samples (7.96%) than Urine samples (5.09%) (X2=9.05 at P=0.05). Volunteers within the age group 26-30 years recorded the highest prevalence (4.46%), while those within the age group 36-40 years recorded the lowest at 1.27%(X2=4.34 at P=0.05). In pregnant female participants, the highest frequency was recorded with those in their 3rd trimester (4.14%), while lowest incidence was recorded for those in their first trimester (0.80%). Antibiogram results from this study showed that C. albicans isolates obtained from this study resisted Fluconazole (72%) more than Voriconazole (57%). Only one out of the six selected isolates yielded resistance in the MIC test. Results obtained from the RT-PCR showed that there was no expression of ERG11 gene among the fluconazole resistant isolates of C. albicans. Observed resistance may be due to other factors other than expression of ERG11 gene.

Keywords: candida, ERG11, triazole, nigeria

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Authors: Yung-Chung Chuang

Abstract:

Current situation and accumulated development of archaeological sites have very high impacts on the preservation value of the site. This research set 3 archaeological sites in Taiwan as study areas. Assessment of the degree of destruction of cultural layers due to land use change and geomorphological change were conducted with aerial photographs (1976-1978; 2016-2017) and digital aerial survey technology on 2D and 3D geographic information system platforms. The results showed that the archaeological sites were all seriously influenced due to the high land use intensity between 1976-2017. Geomorphological changes caused by human cultivation and engineering construction were main causes of site destruction, especially in private lands. Therefore, urban planning methods for land acquisition or land regulation are necessary.

Keywords: archaeological sites, accumulated development, destruction of cultural layers, geomorphological changes

Procedia PDF Downloads 214

Authors: Hamza Arif, Haroon Javaid

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Based on hybrid energy concept of smart grid to synchronize and monitor power being generated at the user end. The ATMEGA328p controller of arduino is used as a processor unit that sends wireless data between user and power utility through NRF24L01 wireless modules. Current and potential transformer circuit are designed to sense the voltage and current at the utility and power being generated at the user end through solar panel. They are designed to interface with the arduino. The approach is used to demonstrate the concept of smart grid and to facilitate for further advancements in the field of smart grid technology. A PWM (Pulse Width Modulation) technique is used to synchronize the user output power with the utility supplier.

Keywords: smart grid, hybrid energy, grid tied inverter, PWM

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Authors: F. Infante, W. Kaal, S. Perfetto, S. Herold

Abstract:

In the last decade the demand of wireless sensors and low-power electric devices for condition monitoring in mechanical structures has been strongly increased. Networks of wireless sensors can potentially be applied in a huge variety of applications. Due to the reduction of both size and power consumption of the electric components and the increasing complexity of mechanical systems, the interest of creating dense nodes sensor networks has become very salient. Nevertheless, with the development of large sensor networks with numerous nodes, the critical problem of powering them is drawing more and more attention. Batteries are not a valid alternative for consideration regarding lifetime, size and effort in replacing them. Between possible alternative solutions for durable power sources useable in mechanical components, vibrations represent a suitable source for the amount of power required to feed a wireless sensor network. For this purpose, energy harvesting from structural vibrations has received much attention in the past few years. Suitable vibrations can be found in numerous mechanical environments including automotive moving structures, household applications, but also civil engineering structures like buildings and bridges. Similarly, a dynamic vibration absorber (DVA) is one of the most used devices to mitigate unwanted vibration of structures. This device is used to transfer the primary structural vibration to the auxiliary system. Thus, the related energy is effectively localized in the secondary less sensitive structure. Then, the additional benefit of harvesting part of the energy can be obtained by implementing dedicated components. This paper describes the design process of an energy harvesting tuned vibration absorber (EHTVA) for rotating systems using piezoelectric elements. The energy of the vibration is converted into electricity rather than dissipated. The device proposed is indeed designed to mitigate torsional vibrations as with a conventional rotational TVA, while harvesting energy as a power source for immediate use or storage. The resultant rotational multi degree of freedom (MDOF) system is initially reduced in an equivalent single degree of freedom (SDOF) system. The Den Hartog’s theory is used for evaluating the optimal mechanical parameters of the initial DVA for the SDOF systems defined. The performance of the TVA is operationally assessed and the vibration reduction at the original resonance frequency is measured. Then, the design is modified for the integration of active piezoelectric patches without detuning the TVA. In order to estimate the real power generated, a complex storage circuit is implemented. A DC-DC step-down converter is connected to the device through a rectifier to return a fixed output voltage. Introducing a big capacitor, the energy stored is measured at different frequencies. Finally, the electromechanical prototype is tested and validated achieving simultaneously reduction and harvesting functions.

Keywords: energy harvesting, piezoelectricity, torsional vibration, vibration absorber

Procedia PDF Downloads 149

Authors: Kholil Kholil, Aniwidayati

Abstract:

MDS (Multi-Dimensional Scaling) is one method that has been widely used to evaluate the use of natural resources. By using Raffish software tool, we will able to analyze sustainability level of the natural resources use. This paper will discuss the level of sustainability of the reservoir using MDS (Multi-Dimensional Scaling) based on five dimensions: (1) Ecology & Layout, (2) Economics, (3) Social & Culture, (4) Regulations & Institutional, and (5) Infrastructure and Technology. MDS analysis results show that the dimension of ecological and layout, institutional and the regulation are lack of sustainability due to the low index score of 45.76 and 42.24. While for the economic, social and culture, and infrastructure and technology dimension reach each score of 63.12, 64.42, and 68.64 (only the sufficient sustainability category). It means that the sustainability performance of Cirata Reservoir seriously threatened.

Keywords: MDS, cirata reservoir, carrying capacity, water quality, sustainable development, sedimentation, sustainability index

Procedia PDF Downloads 384

Authors: Stylianos Galoukas

Abstract:

since the eve of human societies, the need for survival and covering even the most basic needs such as hunting for food, led to the realization of the need for regulation between the personal and common interest. This led to the establishment of initially unwritten and later on, written rules which then became the Law. Transparency as a word has been used for more than 2.500 years. Born in ancient Greece around the 5th BC century and although it was not originally correlated to political or public administration acts, its enclosed principles and rules, were given even then, great attention. In today’s times of fake news and meta-politics, transparency has greatly correlated with the fight against corruption especially in the financially related matters. It is believed however that transparency, being a much wider than corruption meaning, has an even greater role to play than the corruption counterpart. It can be further used to unveil or examine the genuineness of the will towards the public interest, behind every public policy or political act. Therefore, herein the timeless and fundamental principles of institutional and public administration transparency are made clear as well as their application rules that can and ought to be used as evaluation criteria.

Keywords: evaluation citeria, policies, politics, principles, rules, transparency

Procedia PDF Downloads 203

Authors: S. K. Gupta, Richa Bansal

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In a deregulated power system structure, power producers, and customers share a common transmission network for wheeling power from the point of generation to the point of consumption. All parties in this open access environment may try to purchase the energy from the cheaper source for greater profit margins, which may lead to overloading and congestion of certain corridors of the transmission network. This may result in violation of line flow, voltage and stability limits and thereby undermine the system security. Utilities therefore need to determine adequately their Available Transfer Capability (ATC) to ensure that system reliability is maintained while serving a wide range of bilateral and multilateral transactions. This paper presents power transfer distribution factor based on AC load flow for the determination and enhancement of ATC. The study has been carried out for IEEE 24 bus Reliability Test System.

Keywords: available transfer capability, FACTS devices, power transfer distribution factors, electric

Procedia PDF Downloads 500

Authors: Olga Kononova, Sergey Lyapin

Abstract:

Global information society requirements are transparency and reliability of data, as well as ability to manage information resources independently; particularly to search, to analyze, to evaluate information, thereby obtaining new expertise. Moreover, it is satisfying the society information needs that increases the efficiency of the enterprise management and public administration. The study of structurally organized thematic and semantic contexts of different types, automatically extracted from unstructured data, is one of the important tasks for the application of information technologies in education, science, culture, governance and business. The objectives of this study are the contextual knowledge typologization, selection or creation of effective tools for extracting and analyzing contextual knowledge. Explication of various kinds and forms of the contextual knowledge involves the development and use full-text search information systems. For the implementation purposes, the authors use an e-library 'Humanitariana' services such as the contextual search, different types of queries (paragraph-oriented query, frequency-ranked query), automatic extraction of knowledge from the scientific texts. The multifunctional e-library «Humanitariana» is realized in the Internet-architecture in WWS-configuration (Web-browser / Web-server / SQL-server). Advantage of use 'Humanitariana' is in the possibility of combining the resources of several organizations. Scholars and research groups may work in a local network mode and in distributed IT environments with ability to appeal to resources of any participating organizations servers. Paper discusses some specific cases of the contextual knowledge explication with the use of the e-library services and focuses on possibilities of new types of the contextual knowledge. Experimental research base are science texts about 'e-government' and 'computer games'. An analysis of the subject-themed texts trends allowed to propose the content analysis methodology, that combines a full-text search with automatic construction of 'terminogramma' and expert analysis of the selected contexts. 'Terminogramma' is made out as a table that contains a column with a frequency-ranked list of words (nouns), as well as columns with an indication of the absolute frequency (number) and the relative frequency of occurrence of the word (in %% ppm). The analysis of 'e-government' materials showed, that the state takes a dominant position in the processes of the electronic interaction between the authorities and society in modern Russia. The media credited the main role in these processes to the government, which provided public services through specialized portals. Factor analysis revealed two factors statistically describing the used terms: human interaction (the user) and the state (government, processes organizer); interaction management (public officer, processes performer) and technology (infrastructure). Isolation of these factors will lead to changes in the model of electronic interaction between government and society. In this study, the dominant social problems and the prevalence of different categories of subjects of computer gaming in science papers from 2005 to 2015 were identified. Therefore, there is an evident identification of several types of contextual knowledge: micro context; macro context; dynamic context; thematic collection of queries (interactive contextual knowledge expanding a composition of e-library information resources); multimodal context (functional integration of iconographic and full-text resources through hybrid quasi-semantic algorithm of search). Further studies can be pursued both in terms of expanding the resource base on which they are held, and in terms of the development of appropriate tools.

Keywords: contextual knowledge, contextual search, e-library services, frequency-ranked query, paragraph-oriented query, technologies of the contextual knowledge extraction

Procedia PDF Downloads 362