Search results for: posterior distribution

Authors: J. Yan, B. Pieper, B. Bucsky, H. H. Sievers, B. Nasseri, S. A. Mohamed

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In order to optimize the efficacy of medications, the regular follow-up with long-term continuous monitoring of heart rhythmic patterns has been facilitated since clinical introduction of cardiac implantable electronic monitoring devices (CIMD). Extensive analysis of rhythmic circadian properties is capable to disclose the distributions of arrhythmic events, which may support appropriate medication according rate-/rhythm-control strategy and minimize consequent afflictions. 348 patients (69 ± 0.5ys, male 61.8%) with predisposed atrial fibrillation (AF), undergoing primary ablating therapies combined to coronary or valve operations and secondary implantation of CIMDs, were involved and divided into 3 groups such as PAAF (paroxysmal AF) (n=99, male 68.7%), PEAF (persistent AF) (n=94, male 62.8%), and LSPEAF (long-standing persistent AF) (n=155, male 56.8%). All patients participated in three-year ambulant follow-up (3, 6, 9, 12, 18, 24, 30 and 36 months). Burdens of atrial fibrillation recurrence were assessed using cardiac monitor devices, whereby attacks frequencies and their circadian patterns were systemically analyzed. Anticoagulants and regular anti-arrhythmic medications were evaluated and the last were listed in terms of anti-rate and anti-rhythm regimens. Patients in the PEAF-group showed the least AF-burden after surgical ablating procedures compared to both of the other subtypes (p < 0.05). The AF-recurrences predominantly performed such attacks’ property as shorter than one hour, namely within 10 minutes (p < 0.05), regardless of AF-subtypes. Concerning circadian distribution of the recurrence attacks, frequent AF-attacks were mostly recorded in the morning in the PAAF-group (p < 0.05), while the patients with predisposed PEAF complained less attack-induced discomforts in the latter half of the night and the ones with LSPEAF only if they were not physically active after primary surgical ablations. Different AF-subtypes presented distinct therapeutic efficacies after appropriate surgical ablating procedures and recurrence properties in sense of circadian distribution. An optimization of medical regimen and drug dosages to maintain the therapeutic success needs more attention to detailed assessment of the long-term follow-up. Rate-control strategy plays a much more important role than rhythm-control in the ongoing follow-up examinations.

Keywords: atrial fibrillation, CIMD, MAZE, rate-control, rhythm-control, rhythm patterns

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Authors: Shagufta Tabassum, V. P. Pawar, jr., G. N. Shinde

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The study of dielectric relaxation properties of polar liquids in the binary mixture has been carried out at 10, 15, 20 and 25 ºC temperatures for 11 different concentrations using time domain reflectometry technique. The dielectric properties of a solute-solvent mixture of polar liquids in the frequency range of 10 MHz to 30 GHz gives the information regarding formation of monomers and multimers and also an interaction between the molecules of the liquid mixture under study. The dielectric parameters have been obtained by the least squares fit method using the Debye equation characterized by a single relaxation time without relaxation time distribution.

Keywords: excess properties, relaxation time, static dielectric constant, and time domain reflectometry technique

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Authors: H. M. Alfrihidi, H.A. Albarakaty

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Flattening filter-free (FFF) photon beam radiotherapy has increased in the last decade, which is enabled by advancements in treatment planning systems and radiation delivery techniques like multi-leave collimators. FFF beams have higher dose rates, which reduces treatment time. On the other hand, FFF beams have a higher surface dose, which is due to the loss of beam hardening effect caused by the presence of the flatting filter (FF). The possibility of improving FFF beam quality using filters from low-z materials such as steel and aluminium (Al) was investigated using Monte Carlo (MC) simulations. The attenuation coefficient of low-z materials for low-energy photons is higher than that of high-energy photons, which leads to the hardening of the FFF beam and, consequently, a reduction in the surface dose. BEAMnrc user code, based on Electron Gamma Shower (EGSnrc) MC code, is used to simulate the beam of a 6 MV True-Beam linac. A phase-space (phosphor) file provided by Varian Medical Systems was used as a radiation source in the simulation. This phosphor file was scored just above the jaws at 27.88 cm from the target. The linac from the jaw downward was constructed, and radiation passing was simulated and scored at 100 cm from the target. To study the effect of low-z filters, steel and Al filters with a thickness of 1 cm were added below the jaws, and the phosphor file was scored at 100 cm from the target. For comparison, the FF beam was simulated using a similar setup. (BEAM Data Processor (BEAMdp) is used to analyse the energy spectrum in the phosphorus files. Then, the dose distribution resulting from these beams was simulated in a homogeneous water phantom using DOSXYZnrc. The dose profile was evaluated according to the surface dose, the lateral dose distribution, and the percentage depth dose (PDD). The energy spectra of the beams show that the FFF beam is softer than the FF beam. The energy peaks for the FFF and FF beams are 0.525 MeV and 1.52 MeV, respectively. The FFF beam's energy peak becomes 1.1 MeV using a steel filter, while the Al filter does not affect the peak position. Steel and Al's filters reduced the surface dose by 5% and 1.7%, respectively. The dose at a depth of 10 cm (D10) rises by around 2% and 0.5% due to using a steel and Al filter, respectively. On the other hand, steel and Al filters reduce the dose rate of the FFF beam by 34% and 14%, respectively. However, their effect on the dose rate is less than that of the tungsten FF, which reduces the dose rate by about 60%. In conclusion, filters from low-z material decrease the surface dose and increase the D10 dose, allowing for a high-dose delivery to deep tumors with a low skin dose. Although using these filters affects the dose rate, this effect is much lower than the effect of the FF.

Keywords: flattening filter free, monte carlo, radiotherapy, surface dose

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Authors: Mehdi Saeidmanesh, Razali Ismail

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Recently, Graphene Nanoribbon Field Effect Transistors (GNR FETs) attract a great deal of attention due to their better performance in comparison with conventional devices. In this paper, channel length Modulation (CLM) effect on the electrical characteristics of GNR FETs is analytically studied and modeled. To this end, the special distribution of the electric potential along the channel and current-voltage characteristic of the device is modeled. The obtained results of analytical model are compared to the experimental data of published works. As a result, it is observable that considering the effect of CLM, the current-voltage response of GNR FET is more realistic.

Keywords: graphene nanoribbon, field effect transistors, short channel effects, channel length modulation

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Authors: S. S. Sathiesh

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The aim of this project is to study the radiation mechanism synchrotron and Inverse Compton scattering. Theoretically, we discussed spectral energy distribution for both. Programming is done for plotting the graph of Power-law spectrum for synchrotron Radiation using fortran90. The importance of power law spectrum was discussed and studied to infer its physical parameters from the model fitting. We also discussed how to infer the physical parameters from the theoretically drawn graph, we have seen how one can infer B (magnetic field of the source), γ min, γ max, spectral indices (p1, p2) while fitting the curve to the observed data.

Keywords: blazars/quasars, beaming, synchrotron radiation, Synchrotron Self Compton, inverse Compton scattering, mrk421

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Authors: Mouna Mesbahi, M. Loutfi Benkhedir

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In CZTS films solar cell, the preferable reaction between Cu and sulfur vapor was likely to be induced by out diffusion of the bottom Cu component to the surface; this would lead to inhomogeneous distribution of the Cu component to form the Cu2SnS3 secondary phase and formation of many voids and crevices in the resulting CZTS film; which is also the cause of the decline in performance. In this work we study the electronic and optical properties of Cu2SnS3. For this purpose we used the Wien2k code based on the theory of density functional theory (DFT) with the modified Becke-Johnson exchange potential mBJ and the Hubbard potential individually or combined. We have found an energy gap 0.92 eV. The results are in good agreement with experimental results.

Keywords: Cu2SnS3, DFT, electronic and optical properties, mBJ+U, WIEN2K

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Authors: Ahmed A. El-Gindy, Elham S. El-Nashar, Abdallah Nafaa, Sameh El-Kafrawy

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The generation of energy from marine energy became one of the most preferable resources since it is a clean source and friendly to environment. Egypt has long shores along Mediterranean with important cities that need energy resources with significant wave energy. No detailed studies have been done on wave energy distribution in the Egyptian waters. The objective of this paper is to assess the energy wave power available in the Egyptian waters for the choice of the most suitable devices to be used in this area. This paper deals the characteristics and power of the offshore waves in the Egyptian waters. Since the field observations of waves are not frequent and need much technical work, the European Centre for Medium-Range Weather Forecasts (ECMWF) interim reanalysis data in Mediterranean, with a grid size 0.75 degree, which is a relatively course grid, are considered in the present study for preliminary assessment of sea waves characteristics and power. The used data covers the period from 2012 to 2014. The data used are significant wave height (swh), mean wave period (mwp) and wave direction taken at six hourly intervals, at seven chosen stations, and at grid points covering the Egyptian waters. The wave power (wp) formula was used to calculate energy flux. Descriptive statistical analysis including monthly means and standard deviations of the swh, mwp, and wp. The percentiles of wave heights and their corresponding power are done, as a tool of choice of the best technology suitable for the site. The surfer is used to show spatial distributions of wp. The analysis of data at chosen 7 stations determined the potential of wp off important Egyptian cities. Offshore of Al Saloum and Marsa Matruh, the highest wp occurred in January and February (16.93-18.05) ± (18.08-22.12) kw/m while the lowest occurred in June and October (1.49-1.69) ± (1.45-1.74) kw/m. In front of Alexandria and Rashid, the highest wp occurred in January and February (16.93-18.05) ± (18.08-22.12) kw/m while the lowest occurred in June and September (1.29-2.01) ± (1.31-1.83) kw/m. In front of Damietta and Port Said, the highest wp occurred in February (14.29-17.61) ± (21.61-27.10) kw/m and the lowest occurred in June (0.94-0.96) ± (0.71-0.72) kw/m. In winter, the probabilities of waves higher than 0.8 m in percentage were, at Al Saloum and Marsa Matruh (76.56-80.33) ± (11.62-12.05), at Alexandria and Rashid (73.67-74.79) ± (16.21-18.59) and at Damietta and Port Said (66.28-68.69) ± (17.88-17.90). In spring, the percentiles were, at Al Saloum and Marsa Matruh, (48.17-50.92) ± (5.79-6.56), at Alexandria and Rashid, (39.38-43.59) ± (9.06-9.34) and at Damietta and Port Said, (31.59-33.61) ± (10.72-11.25). In summer, the probabilities were, at Al Saloum and Marsa Matruh (57.70-66.67) ± (4.87-6.83), at Alexandria and Rashid (59.96-65.13) ± (9.14-9.35) and at Damietta and Port Said (46.38-49.28) ± (10.89-11.47). In autumn, the probabilities were, at Al Saloum and Marsa Matruh (58.75-59.56) ± (2.55-5.84), at Alexandria and Rashid (47.78-52.13) ± (3.11-7.08) and at Damietta and Port Said (41.16-42.52) ± (7.52-8.34).

Keywords: distribution of sea waves energy, Egyptian Mediterranean waters, waves characteristics, waves power

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Authors: Neelam Kumar

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Science is stratified, with an unequal distribution of research facilities and rewards among scientists. Gender stratification is one of the most prevalent phenomena in the world of science. In most countries gender segregation, horizontal as well as vertical, stands out in the field of science and engineering. India is no exception. This paper aims to examine: (1) gender and science associations, historical as well as contemporary, (2) women’s enrolment and gender differences in selection of academic fields, (2) women as professional researchers, (3) career path and recognition/trajectories. The paper reveals that in recent years the gender–science relationship has changed, but is not totally free from biases. Women’s enrolment into various science disciplines has shown remarkable and steady increase in most parts of the world, including India, yet they remain underrepresented in the S&T workforce, although to a lesser degree than in the past.

Keywords: gender, science, universal, women

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Authors: Katarzyna Miśkiewicz, Magdalena Lasoń-Rydel, Małgorzata Krępska, Katarzyna Sieczyńska, Iwona Masłowska-Lipowicz, Katarzyna Ławińska

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The aim of the study was to analyse a selection of 12 pasteurised products made from fruit and vegetables, such as fruit juices, fruit drinks, jams, marmalades and jam produced by small regional factories as well as large food corporations. The research was carried out as part of the project "Innovative system of healthy and regional food distribution", funded by the Ministry of Education and Science (Poland), which aims to create an economically and organisationally strong agri-food industry in Poland through effective cooperation between scientific and socio-economic actors. The main activities of the project include support for the creation of new distribution channels for regional food products and their easy access to a wide group of potential customers while maintaining the highest quality standards. One of the key areas of the project is food quality analyses conducted to indicate the competitive advantage of regional products. Presented here are studies on the content of sugars, vitamin C, preservatives, synthetic colours, sweeteners, sodium and potassium, as well as studies on the microbiological purity of selected products made from fruit and vegetables. The composition of products made from fruit and vegetables varies greatly and depends on both the type of raw material and the way it is processed. Of the samples tested, fruit drinks contained the least amount of sugars, and jam and marmalade made by large producers and bought in large chain stores contained the most. However, the low sugar content of some fruit drinks is due to the presence of the sweetener sucralose in their composition. The vitamin C content of the samples varied, being higher in products where it was added during production. All products made in small local factories were free of food additives such as preservatives, sweeteners and synthetic colours, indicating their superiority over products made by large producers. Products made in small local factories were characterised by a relatively high potassium content. The microbiological purity of commercial products was confirmed - no Salmonella spp. were detected, and the number of mesophilic bacteria, moulds, yeasts, and β-glucuronidase-positive E. coli was below the limit of quantification.

Keywords: fruit and vegetable products, sugars, food additives, HPLC, ICP-OES

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Authors: Debdut Roy, Vidyasagar Guggilla

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In this research, we highlight our exploratory work on modified zeolite based catalysts for catalytic cracking of hydrocarbons for production of light olefin i.e. ethylene and propylene. The work is focused on understanding the catalyst structure and activity correlation. Catalysts are characterized by surface area and pore size distribution analysis, inductively coupled plasma optical emission spectrometry (ICP-OES), Temperature Programmed Desorption (TPD) of ammonia, pyridine Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermo-gravimetric Analysis (TGA) and correlated with the catalytic activity. It is observed that the yield of lighter olefins increases with increase of Bronsted acid strength.

Keywords: catalytic cracking, zeolite, propylene, structure-activity correlation

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Authors: Shashank Gupta, Carlos Cid, William John Munro

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Quantum distillation is the task of concentrating quantum correlations present in N imperfect copies to M perfect copies (M < N) using free operations by involving all P the parties sharing the quantum correlation. We present a threshold quantum distillation task where the same objective is achieved but using lesser number of parties (K < P). In particular, we give an exact local filtering operations by the participating parties sharing high dimension multipartite entangled state to distill the perfect quantum correlation. Later, we bridge a connection between threshold quantum entanglement distillation and quantum steering distillation and show that threshold distillation might work in the scenario where general distillation protocol like DEJMPS does not work.

Keywords: quantum networks, quantum distillation, quantum key distribution, entanglement distillation

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Authors: Maria Sciammarella, Uttam M. Shrestha, Youngho Seo, Grant T. Gullberg, Elias H. Botvinick

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Background: Myocardial perfusion imaging (MPI) is typically performed with static imaging protocols and visually assessed for perfusion defects based on the relative intensity distribution. Dynamic cardiac SPECT, on the other hand, is a new imaging technique that is based on time varying information of radiotracer distribution, which permits quantification of myocardial blood flow (MBF). In this abstract, we report a progress and current status of dynamic cardiac SPECT using conventional gamma camera (Infinia Hawkeye 4, GE Healthcare) for estimation of myocardial blood flow and coronary flow reserve. Methods: A group of patients who had high risk of coronary artery disease was enrolled to evaluate our methodology. A low-dose/high-dose rest/pharmacologic-induced-stress protocol was implemented. A standard rest and a standard stress radionuclide dose of ⁹⁹ᵐTc-tetrofosmin (140 keV) was administered. The dynamic SPECT data for each patient were reconstructed using the standard 4-dimensional maximum likelihood expectation maximization (ML-EM) algorithm. Acquired data were used to estimate the myocardial blood flow (MBF). The correspondence between flow values in the main coronary vasculature with myocardial segments defined by the standardized myocardial segmentation and nomenclature were derived. The coronary flow reserve, CFR, was defined as the ratio of stress to rest MBF values. CFR values estimated with SPECT were also validated with dynamic PET. Results: The range of territorial MBF in LAD, RCA, and LCX was 0.44 ml/min/g to 3.81 ml/min/g. The MBF between estimated with PET and SPECT in the group of independent cohort of 7 patients showed statistically significant correlation, r = 0.71 (p < 0.001). But the corresponding CFR correlation was moderate r = 0.39 yet statistically significant (p = 0.037). The mean stress MBF value was significantly lower for angiographically abnormal than that for the normal (Normal Mean MBF = 2.49 ± 0.61, Abnormal Mean MBF = 1.43 ± 0. 0.62, P < .001). Conclusions: The visually assessed image findings in clinical SPECT are subjective, and may not reflect direct physiologic measures of coronary lesion. The MBF and CFR measured with dynamic SPECT are fully objective and available only with the data generated from the dynamic SPECT method. A quantitative approach such as measuring CFR using dynamic SPECT imaging is a better mode of diagnosing CAD than visual assessment of stress and rest images from static SPECT images Coronary Flow Reserve.

Keywords: dynamic SPECT, clinical SPECT/CT, selective coronary angiograph, ⁹⁹ᵐTc-Tetrofosmin

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Authors: Krasimir Ivanov, Elitsa Kolentsova, Nguyen Nguyen, Alexander Peltekov, Violina Angelova

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The nanosized zinc hydroxide nitrate has been recently estimated as perspective foliar fertilizer, which has improved zinc solubility, but low phytotoxicity, in comparison with ZnO and other Zn containing compounds. The main problem is obtaining of stable particles with dimensions less than 100 nm. This work studies the effect of preparation conditions on the chemical compositions and particle size of the zinc hydroxide nitrates, prepared by precipitation. Zn(NO3)2.6H2O and NaOH with concentrations, ranged from 0.2 to 3.2M and the initial OH/Zn ratio from 0.5 to 1.6 were used at temperatures from 20 to 60 °C. All samples were characterized in detail by X-ray diffraction, scanning electron microscopy, differential thermal analysis and ICP. Stability and distribution of the zinc hydroxide nitrate particles were estimated too.

Keywords: zinc hydroxide nitrate, nanoparticles, preparation, foliar fertilizer

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Authors: Ronelle Prinsloo

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In South Africa, married retirement fund members can manipulate the legal framework to prevent their spouses from accessing shared retirement benefits during divorce proceedings. The current legal structure allows retirement fund members to accelerate the accrual of their benefits, often by resigning or purchasing living annuities before the finalization of a divorce. This action effectively places these benefits beyond the reach of their spouses, leading to substantial financial prejudice, particularly for financially weaker spouses, typically women. The research highlights that South African courts, including the Supreme Court of Appeal (SCA), have not adequately scrutinized the implications of these actions. Specifically, the SCA has ruled that the capital and proceeds from living annuities are not subject to division during divorce, which undermines the financial rights of non-member spouses. The court's failure to consider the source of the money used to purchase these annuities and its potential inclusion in the joint estate or accrual system is a significant concern. The South African Law Reform Commission has recognized this issue, noting the negative impact on financially weaker spouses. The article critiques the lack of legislative response to this problem despite its significant implications for the equitable distribution of marital assets. The current legal framework, particularly the definition of "pension interest" and the provisions under sections 7(7) and 7(8) of the Divorce Act, is inadequate in addressing the complexities surrounding the sharing of retirement benefits in divorce cases. The article argues for a comprehensive review and reform of the law to ensure that retirement benefits are treated as patrimonial assets, subject to division upon the occurrence of any trigger event, such as resignation, retirement, or retrenchment. The need for such reform is urgent to prevent economically disadvantaged spouses from being unjustly deprived of their fair share of retirement benefits. In conclusion, the article advocates for legislative amendments to the Divorce Act, specifically section 7(7), to clarify that pension interests automatically form part of the joint estate, regardless of whether divorce proceedings are underway. This change would safeguard the financial rights of non-member spouses and ensure a more equitable distribution of retirement benefits during divorce. Failure to address this issue perpetuates economic inequality and leaves financially weaker spouses vulnerable during divorce proceedings.

Keywords: Constitution of South Africa, non-member spouse, retirement benefits, spouse

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Authors: Mina Malak Hanna Saad

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New strategies for supplying banking services to the customer have been brought, which include online banking. Banks have begun to recall electronic banking (e-banking) as a manner to replace some conventional department features by means of the usage of the internet as a brand-new distribution channel. A few clients have at least one account at multiple banks and get admission to those debts through online banking. To test their present-day internet worth, customers need to log into each of their debts, get particular statistics, and paint closer to consolidation. Not only is it time-ingesting; however, but it is also a repeatable activity with a certain frequency. To solve this problem, the idea of account aggregation was delivered as a solution. Account consolidation in e-banking as a form of digital banking appears to build stronger dating with clients. An account linking service is usually known as a service that permits customers to manipulate their bank accounts held at exceptional institutions through a common online banking platform that places a high priority on safety and statistics protection. The object affords an outline of the account aggregation approach in e-banking as a distinct carrier in the area of e-banking. The advanced facts generation is becoming a vital thing in the improvement of financial services enterprise, specifically the banking enterprise. It has brought different ways of delivering banking to the purchaser, which includes net Banking. Banks began to study electronic banking (e-banking) as a means to update some of their traditional branch functions and the use of the net as a distribution channel. Some clients have at least multiple accounts throughout banks and get the right of entry to that money owed through the usage of e-banking offerings. To examine the contemporary internet's well-worth position, customers have to log in to each of their money owed, get the information and work on consolidation. This no longer takes sufficient time; however, it is a repetitive interest at a specified frequency. To address this point, an account aggregation idea is brought as an answer. E-banking account aggregation, as one of the e-banking kinds, appeared to construct a more potent dating with clients. Account Aggregation carrier usually refers to a service that allows clients to control their bank bills maintained in one-of-a-kind institutions via a common Internet banking working platform, with an excessive subject to protection and privateness. This paper offers an overview of an e-banking account aggregation technique as a new provider in the e-banking field.

Keywords: compatibility, complexity, mobile banking, observation, risk banking technology, Internet banks, modernization of banks, banks, account aggregation, security, enterprise developmente-banking, enterprise development

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Authors: Bayoumy Mohamed, Khaled Alam El-Din

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In the present study, 24 years of gridded sea level anomalies (SLA) from satellite altimetry and sea surface temperature (SST) from advanced very-high-resolution radiometer (AVHRR) daily data (1993-2016) are used. These data have been used to investigate the sea level rising and warming rates of SST, and their spatial distribution in the Mediterranean Sea. The results revealed that there is a significant sea level rise in the Mediterranean Sea of 2.86 ± 0.45 mm/year together with a significant warming of 0.037 ± 0.007 °C/year. The high spatial correlation between sea level and SST variations suggests that at least part of the sea level change reported during the period of study was due to heating of surface layers. This indicated that the steric effect had a significant influence on sea level change in the Mediterranean Sea.

Keywords: altimetry, AVHRR, Mediterranean Sea, sea level and SST changes, trend analysis

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Authors: Bailey Houghtaling, Elena Serrano, Vivica Kraak, Samantha Harden, George Davis, Sarah Misyak

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United States (U.S.) Department of Agriculture Supplemental Nutrition Assistance Program (SNAP) participants are low-income Americans receiving federal dollars for supplemental food and beverage purchases. Participants use a variety of (traditional/non-traditional) SNAP-authorized stores for household dietary purchases - also representing food access points for all Americans. Importantly consumers' food and beverage purchases from non-traditional store formats tend to be higher in saturated fats, added sugars, and sodium when compared to purchases from traditional (e.g., grocery/supermarket) formats. Overconsumption of energy-dense and low-nutrient food and beverage products contribute to high obesity rates and adverse health outcomes that differ in severity among urban/rural U.S. locations and high/low-income populations. Little is known about the SNAP-authorized food store format landscape nationally, regionally, or by urban-rural status, as traditional formats are currently used as the gold standard in food access research. This research utilized publicly available U.S. databases to fill this large literature gap and to provide insight into modes of food access for vulnerable U.S. populations: (1) SNAP Retailer Locator which provides a list of all authorized food stores in the U.S., and; (2) Rural-Urban Continuum Codes (RUCC) that categorize U.S. counties as urban (RUCC 1-3) or rural (RUCC 4-9). Frequencies were determined for the highest occurring food store formats nationally and within two regionally diverse U.S. states – Virginia in the east and California in the west. Store format codes were assigned (e.g., grocery, drug, convenience, mass merchandiser, supercenter, dollar, club, or other). RUCC was applied to investigate state-level differences in urbanity-rurality regarding prevalent food store formats and Chi Square test of independence was used to determine if food store format distributions significantly (p < 0.05) differed by region or rurality. The resulting research sample that represented highly prevalent SNAP-authorized food stores nationally included 41.25% of all SNAP stores in the U.S. (N=257,839), comprised primarily of convenience formats (31.94%) followed by dollar (25.58%), drug (19.24%), traditional (10.87%), supercenter (6.85%), mass merchandiser (1.62%), non-food store or restaurant (1.81%), and club formats (1.09%). Results also indicated that the distribution of prevalent SNAP-authorized formats significantly differed by state. California had a lower proportion of traditional (9.96%) and a higher proportion of drug (28.92%) formats than Virginia- 11.55% and 19.97%, respectively (p < 0.001). Virginia also had a higher proportion of dollar formats (26.11%) when compared to California (10.64%) (p < 0.001). Significant differences were also observed for rurality variables (p < 0.001). Prominently, rural Virginia had a significantly higher proportion of dollar formats (41.71%) when compared to urban Virginia (21.78%) and rural California (21.21%). Non-traditional SNAP-authorized formats are highly prevalent and significantly differ in distribution by U.S. region and rurality. The largest proportional difference was observed for dollar formats where the least nutritious consumer purchases are documented in the literature. Researchers/practitioners should investigate non-traditional food stores at the local level using these research findings and similar applied methodologies to determine how access to various store formats impact obesity prevalence. For example, dollar stores may be prime targets for interventions to enhance nutritious consumer purchases in rural Virginia while targeting drug formats in California may be more appropriate.

Keywords: food access, food store format, nutrition interventions, SNAP consumers

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Authors: I. Guemidi, Y. Abdelaziz, T. Rikioui

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In this work, an experimental investigation was carried out to evaluate the mechanical and durability properties of high performance concretes (HPC) containing local southwest Algerian materials. The mechanical properties were assessed from the compressive strength and the flexural strength, whilst the durability characteristics were investigated in terms of sulphate attack. The results obtained allow us to conclude that it is possible to make a high performance concrete (HPC) based on existing materials in the local market, if these are carefully selected and properly mixed in such away to optimize grain size distribution.

Keywords: durability, high performance concrete, high strength, local materials, Southwest Algerian, sulphate attack

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Authors: Merve Küçük, M. Lütfi Öveçoğlu

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Zinc oxide particles were synthesized using the sol-gel method and dip coated on polyester fabric. X-ray diffraction (XRD) analysis revealed a single crystal phase of ZnO particles. Chemical characteristics of the polyester fabric surface were investigated using attenuated total reflection-Fourier transform infrared (ATR-FTIR) measurements. Morphology of ZnO coated fabric was analyzed using field emission scanning electron microscopy (FESEM). After particle analysis, the aqueous ZnO solution resulted in a narrow size distribution at submicron levels. The deposit of ZnO on polyester fabrics yielded a homogeneous spread of spherical particles. Energy dispersive X-ray spectroscopy (EDX) results also affirmed the presence of ZnO particles on the polyester fabrics.

Keywords: dip coating, polyester fabrics, sol gel, zinc oxide

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Authors: S. A. Faizi, S. Yoshitomi

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The optimal design procedure of buckling restrained braces (BRBs) in reinforced concrete (RC) building structures can provide the distribution of horizontal stiffness of BRBs at each story, which minimizes story drift response of the structure under the constraint of specified total stiffness of BRBs. In this paper, a simple rule is proposed to convert continuous horizontal stiffness of BRBs into sectional sizes of BRB which are available from standardized section list assuming realistic structural design stage.

Keywords: buckling restrained brace, building engineering, optimal damper placement, structural engineering

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Authors: Weicheng Luo, Wenzhi Zhao

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Plants growth in desert often suffered from stresses like water deficit, wind erosion and sand burial. Thus, plants in desert always have unique strategies to adapt these stresses. However, data regarding how clonal shrubs withstand wind erosion and sand burial in natural habitats remain relatively scarce. Therefore, we selected a common clonal shrub Calligonum arborescens to study the adaptive strategies of clonal plants to sand dune environment in a transitional zone of desert and Hexi Oasis of China. Our results show that sand burial is one of the essential prerequisites for the survival of C. arborescens rhizome fragments. Both the time and degrees of sand burial and wind erosion had significantly effects on clonal reproduction and growth of C. arborescens. With increasing burial depth, the number of ramets and biomass production significantly decreased. There is same change trend in severe erosion treatments. However, the number of ramets and biomass production significantly increased in moderate erosion treatments. Rhizome severed greatly decreased ramet number and biomass production under both sand burial and severe erosion treatments. That indicated that both sand burial and severe erosion had negative effects on the clonal growth of C. arborescens, but moderate wind erosion had positive effects. And rhizome connections alleviated the negative effects of sand burial and of severe erosion on the growth and performance of C. arborescens. Most fragments of C. arborescens grew in the directions of northeastern and southwestern. Ramet number and biomass, rhizome length and biomass in these two directions were significantly higher than those found in other directions. Interestingly, these directions were perpendicular to the prevailing wind direction. Distribution of C. arborescens differed in different habitats. The total number of individuals was significantly higher in inter-dune areas and on windward slopes than on the top and leeward slopes of dunes; more clonal ramets were produced on the top of dunes than elsewhere, and a few were found on leeward slopes. The mainly reason is that ramets on windward and top of dunes can easily suffered with moderated wind erosion which promoted clonal growth and reproduction of C. arborescens. These results indicated that C. arborescens adapted sand dune environment through directional growth and patchy distribution, and sand-burial and wind erosion were the key factors which led to the directional growth and patchiness of C. arborescens.

Keywords: adaptive strategy, Calligonum arborescens Litv, clonal fragment, desert-oasis transitional zone, sand burial and wind erosion

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Authors: Razaq A. Olaitan, Ayansina Ayanlade

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Understanding aerosol properties is the main goal of global research in order to lower the uncertainty associated with climate change in the trends and magnitude of aerosol particles. In order to identify aerosol particle types, optical properties, and the relationship between aerosol properties and particle concentration between 2019 and 2021, a study conducted in Ilorin, Nigeria, examined the aerosol robotic network's ground-based sun/sky scanning radiometer. The AERONET algorithm version 2 was utilized to retrieve monthly data on aerosol optical depth and angstrom exponent. The version 3 algorithm, which is an almucantar level 2 inversion, was employed to retrieve daily data on single scattering albedo and aerosol size distribution. Excel 2016 was used to analyze the data's monthly, seasonal, and annual mean averages. The distribution of different types of aerosols was analyzed using scatterplots, and the optical properties of the aerosol were investigated using pertinent mathematical theorems. To comprehend the relationships between particle concentration and properties, correlation statistics were employed. Based on the premise that aerosol characteristics must remain constant in both magnitude and trend across time and space, the study's findings indicate that the types of aerosols identified between 2019 and 2021 are as follows: 29.22% urban industrial (UI) aerosol type, 37.08% desert (D) aerosol type, 10.67% biomass burning (BB), and 23.03% urban mix (Um) aerosol type. Convective wind systems, which frequently carry particles as they blow over long distances in the atmosphere, have been responsible for the peak-of-the-columnar aerosol loadings, which were observed during August of the study period. The study has shown that while coarse mode particles dominate, fine particles are increasing in seasonal and annual trends. Burning biomass and human activities in the city are linked to these trends. The study found that the majority of particles are highly absorbing black carbon, with the fine mode having a volume median radius of 0.08 to 0.12 meters. The investigation also revealed that there is a positive coefficient of correlation (r = 0.57) between changes in aerosol particle concentration and changes in aerosol properties. Human activity is rapidly increasing in Ilorin, causing changes in aerosol properties, indicating potential health risks from climate change and human influence on geological and environmental systems.

Keywords: aerosol loading, aerosol types, health risks, optical properties

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Authors: Gaokai Liu

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The distribution of material grain sizes reflects the strength, fracture, corrosion and other properties, and the grain size can be acquired via the grain boundary. In recent years, the automatic grain boundary detection is widely required instead of complex experimental operations. In this paper, an effective solution is applied to acquire the grain boundary of material images. First, the initial superpixel segmentation result is obtained via a superpixel approach. Then, a region merging method is employed to merge adjacent regions based on certain similarity criterions, the experimental results show that the merging strategy improves the superpixel segmentation result on material datasets.

Keywords: grain boundary detection, image segmentation, material images, region merging

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Authors: Shehnila Kanwal

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Murree-Kotli Sattian-Kahta National Park (MKKNP) was declared in 2009. However, not much is known about the diversity and relative abundance of the mammalian fauna of this park. In the current study, we used field sign survey and infrared camera trapping techniques to get an insight into the diversity of mammalian species and their relative abundance. We conducted field surveys in different areas of the park at various elevations from April 2023 up to March 2024 to record the field signs (scats, pug marks etc.) of the mammals’ species; in addition, we deployed a total of 22 infrared trail camera traps in different areas of the park, for 116 nights. We obtained a total of 5201 photographs using camera trapping. Results of camera trapping coupled with field sign surveys confirmed the presence of a total of twenty-one different mammalian species (large, meso and small mammals) recorded in the study area. The common leopard was recorded at four different sites in the park, with an altitudinal range between 648m-1533m. Distribution of Asiatic jackal and a red fox was recorded positive at all the sites surveyed in the park with an altitudinal range between 498m-1287m and 433m-2049m, respectively. Leopard cats were recorded at two different sites within the altitudinal range between 498m-894m. Jungle cat was recorded at three sites within an altitudinal range between 498m-846. Asian palm civets and small Indian civets were both recorded at three sites. Grey mongoose and small Indian mongoose were recorded at four and three sites. We also collected a total of 75 scats of different mammal species in the park to further confirm their occurrence. For the Indian pangolin, we recorded three field burrows at two different sites. Diversity index (H’=2.369960) and species evenness (E=0.81995) were calculated. Analysis of data revealed that wild boar (Sus sucrofa) was the most abundant species in the park; most of the mammal species were found nocturnal; these remain active from dusk throughout the night, and some of them remain active at dawn time. Leopard and Asian palm civets were highly overlapping species in the study area. Their temporal activity pattern overlapped 61%. Barking deer and Indian crested porcupine were also found to be nocturnal species they remained active throughout the night.

Keywords: MKKNP, diversity, abundance, evenness, distribution, mammals, overlapped

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Authors: Meimei Wen, Chang Nyung Kim

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In the current study, three-dimensional liquid metal (LM) magneto-hydrodynamic (MHD) flows in a manifold with three sub-channels under a uniform magnetic field are numerically investigated. In the manifold, the electrical current can cross channel walls, thus having influence on the flow distribution in each sub-channel. A case with various arrangements of electric conductivity for different parts of channel walls is considered, yielding different current distributions as well as flow distributions in each sub-channel. Here, the imbalance of mass flow rates in the three sub-channels is addressed. Meanwhile, predicted are detailed behaviors of the flow velocity, pressure, current and electric potential of LM MHD flows with three sub-channels. Commercial software CFX is used for the numerical simulation of LM MHD flows.

Keywords: CFX, liquid metal, manifold, MHD flow

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Authors: David A. Wallace, Salakjit J. Nilboworn

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Secure and reliable transmission and distribution of electrical power is crucial in today’s ever-increasing demand for electricity. Traditional methods of protecting the electrical grid have relied on relaying systems receiving voltage and current inputs from inductive instruments transformers (IT). This method has provided robust and stable performance throughout the years. Today with the advent of new non-conventional transformers (NCIT) and sensors, the electrical landscape is changing. These new systems have to ability to provide the same electrical performance as traditional instrument transformers with the added features of data acquisition, communication, smaller footprint, lower cost and resistance to GMD/GIC events.

Keywords: non-conventional instrument transformers, digital substations, smart grids, micro-grids

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Authors: M. De Filippo, J. S. Kuang

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In construction industry, reinforced concrete (RC) slabs represent fundamental elements of buildings and bridges. Different methods are available for analysing the structural behaviour of slabs. In the early ages of last century, the yield-line method has been proposed to attempt to solve such problem. Simple geometry problems could easily be solved by using traditional hand analyses which include plasticity theories. Nowadays, advanced finite element (FE) analyses have mainly found their way into applications of many engineering fields due to the wide range of geometries to which they can be applied. In such cases, the application of an elastic or a plastic constitutive model would completely change the approach of the analysis itself. Elastic methods are popular due to their easy applicability to automated computations. However, elastic analyses are limited since they do not consider any aspect of the material behaviour beyond its yield limit, which turns to be an essential aspect of RC structural performance. Furthermore, their applicability to non-linear analysis for modeling plastic behaviour gives very reliable results. Per contra, this type of analysis is computationally quite expensive, i.e. not well suited for solving daily engineering problems. In the past years, many researchers have worked on filling this gap between easy-to-implement elastic methods and computationally complex plastic analyses. This paper aims at proposing a numerical procedure, through which a pseudo-lower bound solution, not violating the yield criterion, is achieved. The advantages of moment distribution are taken into account, hence the increase in strength provided by plastic behaviour is considered. The lower bound solution is improved by detecting over-yielded moments, which are used to artificially rule the moment distribution among the rest of the non-yielded elements. The proposed technique obeys Nielsen’s yield criterion. The outcome of this analysis provides a simple, yet accurate, and non-time-consuming tool of predicting the lower-bound solution of the collapse load of RC slabs. By using this method, structural engineers can find the fracture patterns and ultimate load bearing capacity. The collapse triggering mechanism is found by detecting yield-lines. An application to the simple case of a square clamped slab is shown, and a good match was found with the exact values of collapse load.

Keywords: computational mechanics, lower bound method, reinforced concrete slabs, yield-line

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Authors: Richard Pincak

Abstract:

Starting from a 4D spacetime model using a partially negative dimensional product manifold (PNDP-manifold), which emerges as a 2D spacetime, we developed an analysis of tidal forces and Hawking radiation near the event horizon of a Schwarzchild black hole. The modified 2D metric, incorporating the effects of the four-dimensional Weyl tensor, with the dilatonic field and the newly derived time relation \(2\alpha t = \ln \epsilon\), can enable a deeper understanding of quantum gravity. The analysis shows how the modified Hawking temperature and distribution of emitted particles are affected by additional fields, providing potential observables for future experiments.

Keywords: black holes, Hawking radiation, Weyl tensor, information paradox

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Authors: Jianwen Li, Hongfang Ma, Weixin Qian, Haitao Zhang, Weiyong Ying

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Methanol-to-propylene conversion was carried out in a continuous-flow fixed-bed reactor over nano-sized HZSM-5 zeolites. The HZSM-5 catalysts were synthesized with different Si/Al ratio and silicon sources, and treated with NaOH. The structural property, morphology, and acidity of catalysts were measured by XRD, N₂ adsorption, FE-SEM, TEM, and NH₃-TPD. The results indicate that the increment of Si/Al ratio decreased the acidity of catalysts and then improved propylene selectivity, while silicon sources had slight impact on the acidity but affected the product distribution. The desilication after alkali treatment could increase intracrystalline mesopores and enhance propylene selectivity.

Keywords: alkali treatment, HZSM-5, methanol-to-propylene, synthesis condition

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Authors: Rebeca Ramirez Acosta, Sebastian Lenhoff

Abstract:

Decision makers worldwide need to determine if the implementation of a new market mechanism will contribute to the sustainability and resilience of the power system. Due to smart grid technologies, new products in the distribution and transmission system can be traded; however, the impact of changing a market rule will differ between several regions. To test systematically those impacts, a market categorization has been compiled and organized in a smart grid market testing toolbox. This toolbox maps all actual energy products and sets the basis for running a co-simulation test with the new rule to be implemented. It will help to measure the impact of the new rule, based on the sustainable and resilience indicators.

Keywords: co-simulation, electricity market, smart grid market, market testing

Procedia PDF Downloads 190