Search results for: diffusion driven instability

Authors: Nadjib Dahdouh, Samira Amokrane, Elhadj Mekatel, Djamel Nibou

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The removal of Basic Yellow 28 (BY28) from aqueous solutions by plastic wastes PMMA was investigated. The characteristics of plastic wastes PMMA were determined by SEM, FTIR and chemical composition analysis. The effects of solution pH, initial Basic Yellow 28 (BY28) concentration C, solid/liquid ratio R, and temperature T were studied in batch experiments. The Freundlich and the Langmuir models have been applied to the adsorption process, and it was found that the equilibrium followed well Langmuir adsorption isotherm. A comparison of kinetic models applied to the adsorption of BY28 on the PMMA was evaluated for the pseudo-first-order and the pseudo-second-order kinetic models. It was found that used models were correlated with the experimental data. Intraparticle diffusion model was also used in these experiments. The thermodynamic parameters namely the enthalpy ∆H°, entropy ∆S° and free energy ∆G° of adsorption of BY28 on PMMA were determined. From the obtained results, the negative values of Gibbs free energy ∆G° indicated the spontaneity of the adsorption of BY28 by PMMA. The negative values of ∆H° revealed the exothermic nature of the process and the negative values of ∆S° suggest the stability of BY28 on the surface of SW PMMA.

Keywords: removal, Waste PMMA, BY28 dye, equilibrium, kinetic study, thermodynamic study

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Authors: Faisal Bin Alam

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Most of the manufacturing entities cause negative footprint to nature that demand due attention. Textile industries have one of the longest supply chains and bear the liability of significant environmental impact to our planet. Issues of environmental safety, scarcity of energy and resources, and demand for eco-friendly products have driven research to search for safe and suitable alternatives in apparel processing. Consumer awareness, increased pressure from fashion brands and actions from local legislative authorities have somewhat been able to improve the practices. Objective of this paper is to reveal the best selection of raw materials and methods of production, taking environmental sustainability into account. Methodology used in this study is exploratory in nature based on personal experience, field visits in the factories of Bangladesh and secondary sources. Findings are limited to exploring better alternatives to conventional operations of a Readymade Garment manufacturing, from fibre selection to final product delivery, therefore showing some ways of achieving greener environment in the supply chain of a clothing industry.

Keywords: textile and apparel, environmental sustainability, supply chain, production, clothing

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Authors: C. Y. Ng, A. M. Johan, A. E. Kajuputra

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Wave-in-deck phenomenon for fixed jacket platforms at shallow water condition has been reported as a notable risk to the workability and reliability of the platform. Reduction in reservoir pressure, due to the extraction of hydrocarbon for an extended period of time, has caused the occurrence of seabed subsidence. Platform experiencing subsidence promotes reduction of air gaps, which eventually allows the waves to attack the bottom decks. The impact of the wave-in-deck generates additional loads to the structure and therefore increases the values of the moment arms. Higher moment arms trigger instability in terms of overturning, eventually decreases the reserve strength ratio (RSR) values of the structure. The mechanics of wave-in-decks, however, is still not well understood and have not been fully incorporated into the design codes and standards. Hence, it is necessary to revisit the current design codes and standards for platform design optimization. The aim of this study is to evaluate the effects of RSR due to wave-in-deck on four-legged jacket platforms in Malaysia. Base shear values with regards to calibration and modifications of wave characteristics were obtained using SESAM GeniE. Correspondingly, pushover analysis is conducted using USFOS to retrieve the RSR. The effects of the contributing factors i.e. the wave height, wave period and water depth with regards to the RSR and base shear values were analyzed and discussed. This research proposal is important in optimizing the design life of the existing and aging offshore structures. Outcomes of this research are expected to provide a proper evaluation of the wave-in-deck mechanics and in return contribute to the current mitigation strategies in managing the issue.

Keywords: wave-in-deck loads, wave effects, water depth, fixed jacket platforms

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Authors: Iqbal Ahmed Chowdhury

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Diarrhea is considered to be one of the influential factors of child death in Bangladesh. While it is known that diarrhea is a water-driven disease, due to the lack of studies, little is known about the extent to which various feeding patterns contribute to such an incidence. Our paper intends to fill this gap by looking into different feeding patterns and their influence on diarrhea incidence among children in Bangladesh. Using data collected for the Demographic and Health Survey, 2014, this paper reveals that feeding patterns can influence the diarrhea incidence among this group of children to a great extent. This paper finds that the incidence of diarrhea is likely to elevate if diarrhea-affected children are fed plain water from any source and any kind of juice. However, breastfeeding, feeding soup or clear broth, prescribed baby food, and clean water from a tube well tend to help fight diarrhea incidence among children in Bangladesh. The results are found to be consistent even after controlling for sociodemographic variables, including age and sex of children, age and education qualification of the parent, and the number of children in the family. The results of this study could contribute to treating diarrhea among children in Bangladesh as well as similar other countries in the world.

Keywords: feeding patterns, diarrhea, Bangladesh, children

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Authors: Luther Ollier, Sylvie Thiria, Anastase Charantonis, Carlos E. Mejia, Michel Crépon

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Sea Surface Height Anomaly (SLA) is a signature of the sub-mesoscale dynamics of the upper ocean. Sea Surface Temperature (SST) is driven by these dynamics and can be used to improve the spatial interpolation of SLA fields. In this study, we focused on the temporal evolution of SLA fields. We explored the capacity of deep learning (DL) methods to predict short-term SLA fields using SST fields. We used simulated daily SLA and SST data from the Mercator Global Analysis and Forecasting System, with a resolution of (1/12)◦ in the North Atlantic Ocean (26.5-44.42◦N, -64.25–41.83◦E), covering the period from 1993 to 2019. Using a slightly modified image-to-image convolutional DL architecture, we demonstrated that SST is a relevant variable for controlling the SLA prediction. With a learning process inspired by the teaching-forcing method, we managed to improve the SLA forecast at five days by using the SST fields as additional information. We obtained predictions of a 12 cm (20 cm) error of SLA evolution for scales smaller than mesoscales and at time scales of 5 days (20 days), respectively. Moreover, the information provided by the SST allows us to limit the SLA error to 16 cm at 20 days when learning the trajectory.

Keywords: deep-learning, altimetry, sea surface temperature, forecast

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Authors: Samuel K. Degife, Kamal K. Pant, Sapna Jain

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The world´s population and industrialization of countries continued to grow in an alarming rate irrespective of the security for food, energy supply, and pure water availability. As a result, the global energy consumption is observed to increase significantly. Fossil energy resources that mainly comprised of crude oil, coal, and natural gas have been used by mankind as the main energy source for almost two centuries. However, sufficient evidences are revealing that the consumption of fossil resource as transportation fuel emits environmental pollutants such as CO2, NOx, and SOx. These resources are dwindling rapidly besides enormous amount of problems associated such as fluctuation of oil price and instability of oil-rich regions. Biomass is a promising renewable energy candidate to replace fossil-based transportation fuel and chemical production. The present study aims at valorization of hexose sugars (glucose and fructose) using zeolite based catalysts in imidazolium based ionic liquid (1-butyl-3-methylimidazolium chloride, [BMIM] Cl) reaction media. The catalytic effect chromium impregnated H-ZSM-5 (Cr/H-ZSM-5) was studied for dehydration of hexose sugars. The wet impregnation method was used to prepare Cr/H-ZSM-5 catalyst. The characterization of the prepared catalyst was performed using techniques such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction analysis (XRD), Temperature-programmed desorption of ammonia (NH3-TPD) and BET-surface area analysis. The dehydration product, 5-hydroxymethylfurfural (5-HMF), was analyzed using high-performance liquid chromatography (HPLC). Cr/H-ZSM-5 was effective in dehydrating fructose with 87% conversion and 55% yield 5-HMF at 180 oC for 30 min of reaction time compared with H-ZSM-5 catalyst which yielded only 31% of 5-HMF at identical reaction condition.

Keywords: chromium, hexose, ionic liquid, , zeolite

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Authors: Mamta M. Barapatre, V. N. Sahare

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Since from long time two wheeled vehicle self-balancing has always been a back-breaking task for both human and robots. Leaning a bicycle driving is long time process and goes through building knowledge base for parameter decision making while balancing robots. In order to create this machine learning phase with embedded system the proposed system is designed. The system proposed aims to construct a bicycle automaton, power-driven by an electric motor, which could balance by itself and move along a specific path. This path could be wavy with bumps and varying widths. The key aim was to construct a cycle which self-balances itself by controlling its handle. In order to take a turn, the mass was transferred to the center. In order to maintain the stability, the bicycle bot automatically turned the handle and a turn. Some problems were faced by the team which were Speed, Steering mechanism through mass- distribution (leaning), Center of mass location and gyroscopic effect of its wheel. The idea proposed have potential applications in automation of transportation system and is most efficient.

Keywords: gyroscope-flywheel, accelerometer, servomotor-controller, self stability concept

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Authors: Maram Saleh

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Knowledge has become an essential resource in today’s economy and become the most important asset of maintaining competition advantage in organizations. The importance of knowledge has made organizations to manage their knowledge assets and resources through all multiple knowledge management stages such as: Knowledge Creation, knowledge storage, knowledge sharing and knowledge use. Researches on data mining are continues growing over recent years on both business and educational fields. Data mining is one of the most important steps of the knowledge discovery in databases process aiming to extract implicit, unknown but useful knowledge and it is considered as significant subfield in knowledge management. Data miming have the great potential to help organizations to focus on extracting the most important information on their data warehouses. Data mining tools and techniques can predict future trends and behaviors, allowing businesses to make proactive, knowledge-driven decisions. This review paper explores the applications of data mining techniques in supporting knowledge management process as an effective knowledge discovery technique. In this paper, we identify the relationship between data mining and knowledge management, and then focus on introducing some application of date mining techniques in knowledge management for some real life domains.

Keywords: Data Mining, Knowledge management, Knowledge discovery, Knowledge creation.

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Authors: Dae-Gyun Ahn, Eun-Teak Woo, Yun-Hyun Cho, Seung-Ho Han

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For the sustainable development of wind energy, energy industries have invested in the development of highly efficient wind generators such as the Axial Flux Permanent Magnet (AFPM) generator. The AFPM generator, however, has a history of overheating on the surface of the stator, so that power production decreases significantly. A proper cooling system, therefore, is needed. Although a convective-type cooling system has been developed, the size of the air blower must be increased when the generator’s capacity exceeds 2.5MW. In this study, a newly developed conductive-type cooling system was proposed for the 2.5MW AFPM generator installed on an offshore wind turbine. Through electromagnetic thermal analysis, the efficiency of the heat transfer on the stator surface was investigated. When using the proposed cooling system, the temperatures on the stator surface and on the permanent magnet under conditions of thermal saturation were 76 and 66 C, respectively. (KETEP 20134030200320)

Keywords: heat transfer, thermal analysis, axial flux permanent magnet, conductive-type cooling system

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Authors: R. Vidhya

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Diasporic writings present a comprehensive view of social, cultural and psychological dualities of immigrants. Isolation and the strong feelings of insecurity and inferiority due to constant marginalization coupled with a nostalgia for their motherland, its customs, culture, language, food and people which keep haunting the minds of immigrants are the major themes that are handled by diasporic writers. In the African diaspora, more than the men, it is the women who face the brunt and burden of the triple jeopardy – the racial, class and gender discrimination. Women writers from Africa have successfully sketched the plight of African women in the diaspora. Buchi Emecheta, a Nigerian woman writer deftly portrays the African Diaspora in her novels. She skillfully weaves her stories with her own experiences as an immigrant in the United Kingdom. She portrays the immigrant life and psychology through numerous themes like exile, geographical shift of locations, transactions of culture, political instability and the dilemma of moral and religious ideologies in her diasporic novels Second-class Citizen, Gwendolyn and Kehinde. The contemporary Nigerian woman writer Chimamanda Ngozi Adichie has also dexterously depicted the diasporic dilemma of her protagonist Ifemelu in Americannah, who initially has the experience of a despondent and a downcast in the United States of America. This paper aims to analyse the diasporic sentiments and sensibilities of the Nigerian Igbo women writers Buchi Emecheta and Chimamanda Ngozi Adichie whose women characters finally find emancipation and empowerment in the African Diaspora. This study is based on the Africana Womanist Literary theory propounded by Clenora Hudson-Weems.

Keywords: African Diaspora, Nigerian women writers, Buchi Emecheta, Chimamanda Ngozi Adichie, emancipation, empowerment

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Authors: Pun Jankrajangjaeng

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Senna garrettiana is a climatic tropical plant in Southeast Asia. Senna garrettiana (Craib) is used as a medicinal plant in Thailand, in which the experiment reported that the plant contains triterpenoids, ligans, phenolics, and fungal metabolites. Thus, it is also reported that the plant possesses interesting biological activity such as antioxidant activity. Therefore, Senna garrettiana is selected to examine the antimicrobial activity. The purpose of this study is to examine the antimicrobial activity of Senna garrettiana (crab) extract against Gram-positive Staphylococcus aureus and Gram-negative Salmonella typhi, and the fungus Candida albicans. This study performed the agar disk-diffusion method and broth microdilution by using five concentrations of plant extract to determine the minimum inhibitory concentration (MIC) of S. garrettiana extract. The result showed that S. garrettiana extract gave the maximum zone inhibition of 11.7 mm, 13.7 mm, and 14.0 mm against S. aureus, S. typhi, and C. albicans, respectively. The MIC value of S. garrettiana against S. aureus was 125 µg/mL while the MIC in S. typhi and C. albicans greater than 2000 µg/mL. To conclude, S. garrettiana extract showed higher sensitivity of antibacterial activity against gram-positive bacteria than gram-negative bacteria. In addition, the plant extracts also possessed antifungal activity. Therefore, further investigation to confirm the mechanism of action of antimicrobial activity in S. garrettiana extract should be performed to identify the target of the antimicrobial action.

Keywords: antimicrobial activity, Candida albicans, Salmonella typhi, Senna garrettiana, Staphylococcus aureus

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Authors: Xizhen Zhou, Yanjie Ji

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The charging behavior of drivers provides a reference for the planning and management of charging facilities. Based on the real trajectory data of electric vehicles, this study explored the influence of the surrounding environments of the parking spot on charging decisions. The built environment, the condition of vehicles, and the nearest charging station were all considered. And the mixed binary logit model was used to capture the impact of unobserved heterogeneity. The results show that the number of fast chargers in the charging station, parking price, dwell time, and shopping services all significantly impact the charging decision, while the leisure services, scenic spots, and mileage since the last charging are opposite. Besides, factors related to unobserved heterogeneity include the number of fast chargers, parking and charging prices, residential areas, etc. The interaction effects of random parameters further illustrate the complexity of charging choice behavior. The results provide insights for planning and managing charging facilities.

Keywords: charging decision, trajectory, electric vehicle, infrastructure, mixed logit

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Authors: Nino M. Pizarro

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To the author’s knowledge, despite the written documents about Marist spirituality/charism, nothing has been done concerning a clear theoretical framework that highlights Marist spirituality/charism from the perspective or lived experience of the lay Marists of St. Marcellin Champagnat. The participants of the study are the lay Marist - educators who are from Marist Schools in the Philippines. Since the study would like to find out the respondents’ own concepts and meanings about Marist spirituality/charism, qualitative methodology is considered the approach to be used in the study. In particular, the study will use the qualitative methods of Barney Glaser. The theory will be generated systematically from data collection, coding and analyzing through memoing, theoretical sampling, sorting and writing and using the constant comparative method. The data collection method that will be employed in this grounded theory research is the in-depth interview that is semi-structured and participant driven. Data collection will be done through snowball sampling that is purposive. The study is considering to come up with a theoretical framework that will help the lay Marists to deepen their understanding of the Marist spirituality/charism and their vocation as lay partners of the Marist Brothers of the Schools.

Keywords: grounded theory, Lay Marists, lived experience, Marist spirituality/charism

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Authors: Kateryna Pilyarchuk

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A dress has, since times immemorial, been used to communicate the wearer’s identity. When a new trend is born, fashionistas buy it not only with the purpose to beautify themselves, but also to acquire the collective identity. Fashion has become a means of narrating one’s stance and status. Thus, when one spends money on a brand, one pays for some unmaterial components associated with it. This paper will present some ways in which fashion magazines promote consumerism by drawing on women’s craving for collective identity and need to fill in their identity gap by means of a purchase. By applying the method of critical discursive psychology, it will present layers of ideology and positions that become visible in framing of the message in U.S. Harper’s Bazaar. In this context, fashion decisions that are presented to its readers will be critically evaluated from the gender perspective. It will be demonstrated that what is presented as a postfeminist choice in the neoliberal society is still, to a considerable extent, oppressive and driven by the male gaze. As the findings show, the contemporary female identities in fashion are still built on the principles of traditional femininity. Magazines and fashion discourse train women that they should fear being left out of fashion and, by extension, out of the category of the sexually appealing (from the male perspective).

Keywords: collective identity, critical discursive psychology, fashion discourse, identity gap

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Authors: Lee Sunghyoun, Yu Byeongkee, Kim Hyuckjoo, Yun Namkyu, Jung Jongcheon

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Most of the recent on-sale oyster mushrooms are raised in a oyster mushroom house, in which the necessary adjustment of growing condition is feasible. The rationale for such artificial growing is the impossibility of successive cultivation in the case of a natural cultivation due to external weather conditions. A oyster mushroom house adopts an equipment called growing bed, laying one growing bed upon another in a multi-column fashion, growing and developing the mushrooms on the respective equipments. The indispensable environment management factors of mushroom cultivation are temperature, humidity, and CO2; on which an appropriate regulation of the three requisites is a necessitated condition for the sake of the total output’s increase. However, due to the multiple layers of growing bed’s disturbance on air circulation, a oyster mushroom house’s internal environmental uniformity meets with considerable instability. This research presents a technology which assures the facilitation of environment regulation over all the internal space of a oyster mushroom house, irrespective of its location. The research staff reinforced the oyster mushroom house’s insulation in order to minimize the external environment’s influence on the oyster mushroom house’s internal environment and installed circulation fan to improve the oyster mushroom house’s interior environmental uniformity. Also, the humidifier nozzle’s position was set to prevent dew condensation when humidifying. As a result, a highly sophisticated management over all the oyster mushroom house‘s internal space was realized with the temperature of 0.2~1.3℃, and the relative humidity of 2~7% at the cultivating stage of mushroom’s growth. Therefore, to maximize oyster mushroom house‘s internal environmental uniformity, it can be concluded that consideration of various factors such as insulation reinforcement, decision on the humidifier nozzle’s location, disposition of circulation fan’s installation and the direction of wind discharge is needed.

Keywords: mushroom growing facility, environmental uniformity, temperature, relative humidity, CO2 concentration

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Authors: Khiaira S. Hassan, Abbas S. Alwan, Muna K. Abbass

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This research aims to study the effect of the liquid nitriding and shot peening on the hardness, surface roughness, residual stress, microstructure and corrosion behavior of austenite stainless steel 316 L. Chemical surface heat treatment by liquid nitriding process was carried out at 500 °C for 1 h and followed by shot peening with using ball steel diameter of 1.25 mm in different exposure time of 10 and 20 min. Electrochemical corrosion test was applied in sea water (3.5% NaCl solution) by using potentostat instrument. The results showed that the nitride layer consists of a compound layer (white layer) and diffusion zone immediately below the alloy layer. It has been found that the mechanical treatment (shot peening) has led to the formation of compressive residual stresses in layer surface that increased the hardness of stainless steel surface. All surface treatment (nitriding and shot peening) processes have led to the formation of carbide of CrN in hard surface layer. It was shown that both processes caused an increase in surface hardness and roughness which increases with shot peening time. Also, the corrosion results showed that the liquid nitriding and shot peening processes increase the corrosion rate to values more than that of not treated stainless steel.

Keywords: stainless steel 316L, shot peening, nitriding, corrosion, hardness

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Authors: Shrikant V. Sangludkar, Dilip I. Sangotra, Sachin T. Bagde, Abhijeet A. Khandagale

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The paper discloses a controlled tracked humanoid robot moving platform. A driving and driven wheel are controlled by a control module to drive a robot body to move according to data signals of a monitoring module, in addition, remote transmission can be achieved, and a certain remote control function can be realized. A power management module circuit board looks after in used for providing electric drive for moving of the robot body and distribution of separate power source to be used in internal of robot system. An external port circuit board is arranged, the tracked robot moving platform can be used immediately for any data acquisition. The moving platform is simple and compact in structure, strong in adaptation performance, stable in operation and suitable for being operated in severe environments. Meanwhile, a layered modular installation structure is adopted, and therefore the moving platform is convenient to assemble and disassemble.

Keywords: moving platform, humanoid robot, embedded controlled drive, mobile robot, museum robots, self-localization, obstacle avoidance, communication

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Authors: Azza M. Atya, Mahmoud M. Nasser

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Background/ /Significance: Peripheral neuropathy is one of the long term serious complications of diabetes, which may attribute to postural instability and alteration of planter pressure. Whole body vibration (WBV) is a somatosensory stimulation type of exercise that has been emerged in sport training and rehabilitation of neuromuscular disorders. Purpose: The aim of this study was to investigate the effect of whole Body Vibration on antroposterior (AP), mediolateral (ML) posture stability and planter foot pressure in patients with diabetic neuropathy. Subjects: forty diabetic patients with moderate peripheral neuropathy aged from 35 to 50 years, were randomly assigned to WBV group (n=20) and control group (n=20). Methods and Materials: the WBV intervention consisted of three session weekly for 8 weeks (frequency 20 Hz, peak-to peak displacement 4mm, acceleration 3.5 g). Biodex balance system was used for postural stability assessment and the foot scan plate was used to measure the mean peak pressure under the first and lesser metatarsals. The main Outcome measures were antroposterior stability index (APSI), mediolateral stability index (MLSI), overall stability index (OSI),and mean peak foot pressure. Analyses: Statistical analysis was performed using the SPSS software package (SPSS for Windows Release 18.0). T-test was used to compare between the pre- and post-treatment values between and within groups. Results: For the 40 study participants (18male and 22 females) there were no between-group differences at baseline. At the end of 8 weeks, Subjects in WBV group experienced significant increase in postural stability with a reduction of mean peak of planter foot pressure (P<0.05) compared with the control group. Conclusion: The result suggests that WBV is an effective therapeutic modality for increasing postural stability and reducing planter pressure in patients with diabetic neuropathy.

Keywords: whole body vibration, diabetic neuropathy, posture stability, foot pressure

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Authors: Patrizia Frontera, Anastasia Macario, Simona Crispi, Angela Malara, Pierantonio De Luca, Stefano Trocino

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The exploration of solar energy for the photoelectrochemical splitting of water into hydrogen and oxygen has been extensively researched as a means of generating sustainable H₂ fuel. However, despite these efforts, commercialization of this technology has not yet materialized. Presently, the primary impediments to commercialization include low solar-to-hydrogen efficiency (2-3% in PEC with an active area of up to 10-15 cm²), the utilization of costly and critical raw materials (e.g., BiVO₄), and energy losses during the separation of H₂ from O₂ and H₂O vapours in the output stream. The SERGIO partners have identified an advanced approach to fabricate photoelectrode materials, coupled with an appropriate scientific direction to achieve cost-effective solar-driven H₂ production in a tandem photoelectrochemical cell. This project is designed to reach Technology Readiness Level (TRL) 4 by validating the technology in the laboratory using a cell with an active area of up to 10 cm², boasting a solar-to-hydrogen efficiency of 5%, and ensuring acceptable hydrogen purity (99.99%). Our objectives include breakthroughs in cost efficiency, conversion efficiency, and H₂ purity.

Keywords: photoelectrolysis, green hydrogen, photoelectrochemical cell, semiconductors

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Authors: Mohd Tariq

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The three phase system drives produce the problem of more torque pulsations and harmonics. This issue prevents the smooth operation of the drives and it also induces the amount of heat generated thus resulting in an increase in power loss. Higher phase system offers smooth operation of the machines with greater power capacity. Five phase variable-speed induction motor drives are commonly used in various industrial and commercial applications like tractions, electrical vehicles, ship propulsions and conveyor belt drive system. In this work, a comparative analysis of the different modulation schemes applied on the five-level five-phase Packed U Cell (PUC) inverter fed induction motor drives is presented. The performance of the inverter is greatly affected with the modulation schemes applied. The system is modeled, designed, and implemented in MATLAB^®/Simulink environment. Experimental validation is done for the prototype of single phase, whereas five phase experimental validation is proposed in the future works.

Keywords: Packed U-Cell (PUC) inverter, five-phase system, pulse width modulation (PWM), induction motor (IM)

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Authors: Craig M. Allen

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Twenty two African entrepreneurs with Small and Medium Enterprises (SMEs) in a single social network centered around a non-Muslim population in a smaller African country, selected an Islamic financing structure, a form of Murabaha, based solely on market rationale. These entrepreneurs had all won procurement contracts from major purchasers of goods within their country and faced difficulty arranging traditional bank financing to support their supply-chain needs. The Murabaha-based structure satisfied their market-driven demand and provided an attractive alternative to the traditional bank-offered lending products. The Murabaha-styled trade-financing structure was not promoted with any religious implications, but solely as a market solution to the existing problems associated with bank-related financing. This indicates the strong market forces that draw SMEs to financing structures that are traditionally considered within the framework of Islamic finance.

Keywords: Africa, entrepreneurs, Islamic finance, market acceptance, Murabaha, SMEs

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Authors: Dimitrios I. Tselentis, Simon P. Washington

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Considerable literature has been focused over the last few decades on forecasting the consumer demand of Energy Efficient Vehicles (EEVs). These methodological issues range from how to capture recent purchase decisions in revealed choice studies and how to set up experiments in stated preference (SP) studies, and choice of analysis method for analyzing such data. This paper reviews the plethora of published studies on the field of forecasting demand of EEVs since 1980, and provides a review and annotated bibliography of that literature as it pertains to this particular demand forecasting problem. This detailed review addresses the literature not only to Transportation studies, but specifically to the problem and methodologies around forecasting to the time horizons of planning studies which may represent 10 to 20 year forecasts. The objectives of the paper are to identify where existing gaps in literature exist and to articulate where promising methodologies might guide longer term forecasting. One of the key findings of this review is that there are many common techniques used both in the field of new product demand forecasting and the field of predicting future demand for EEV. Apart from SP and RP methods, some of these new techniques that have emerged in the literature in the last few decades are survey related approaches, product diffusion models, time-series modelling, computational intelligence models and other holistic approaches.

Keywords: demand forecasting, Energy Efficient Vehicles (EEVs), forecasting methodologies review, methodological approaches

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Authors: Md Murshed Bhuyan, Hirotaka Okabe, Yoshiki Hidaka, Kazuhiro Hara

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Pectin-Acrylamide- (Vinyl Phosphonic Acid) Hydrogels were prepared from their blend by using gamma radiation of various doses. It was found that the gel fraction of hydrogel increases with increasing the radiation dose reaches a maximum and then started decreasing with increasing the dose. The optimum radiation dose and the composition of raw materials were determined on the basis of equilibrium swelling which resulted in 20 kGy absorbed dose and 1:2:4 (Pectin:AAm:VPA) composition. Differential scanning calorimetry reveals the gel strength for using them as the adsorbent. The FTIR-spectrum confirmed the grafting/ crosslinking of the monomer on the backbone of pectin chain. The hydrogels were applied in adsorption of Al, Ga, and In from multielement solution where the adsorption capacity order for those three elements was found as – In>Ga>Al. SEM images of hydrogels and metal adsorbed hydrogels indicate the gel network and adherence of the metal ions in the interpenetrating network of the hydrogel which were supported by EDS spectra. The adsorption isotherm models were studied and found that the Langmuir adsorption isotherm model was well fitted with the data. Adsorption data were also fitted to different adsorption kinetic and diffusion models. Desorption of metal adsorbed hydrogels was performed in 5% nitric acid where desorption efficiency was found around 90%.

Keywords: hydrogel, gamma radiation, vinyl phosphonic acid, metal adsorption

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Authors: Isabelle Snyder, Travis Smith

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Microgrid protection presents challenges to conventional protection techniques due to the low-induced fault current. Protection relays present in microgrid applications require a combination of settings groups to adjust based on the architecture of the microgrid in islanded and grid-connected modes. In a radial system where the microgrid is at the other end of the feeder, directional elements can be used to identify the direction of the fault current and switch settings groups accordingly (grid-connected or microgrid-connected). However, with multiple microgrid connections, this concept becomes more challenging, and the direction of the current alone is not sufficient to identify the source of the fault current contribution. ORNL has previously developed adaptive relaying schemes through other DOE-funded research projects that will be evaluated and used as a baseline for this research. The four protection techniques in this study are labeled as follows: (1) Adaptive Current only Protection System (ACPS), Intentional (2) Unbalanced Control for Protection Control (IUCPC), (3) Adaptive Protection System with Communication Controller (APSCC) (4) Adaptive Model-Driven Protective Relay (AMDPR).

Keywords: adaptive relaying, microgrid protection, sequence components, islanding detection

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Authors: Hanei Son

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Since the beginning of the 2010s, ‘start-up boom’ has continued with the creation of many new enterprises in Korea. Such tendency was led by various changes in society such as emergence and diffusion of smartphones. Especially, the Korean government has been interested in start-ups and entrepreneurship as an alternative engine for Korea's economic growth. With strong support from the government, as a result, many new enterprises have been established for recent years and the Korean government seems to have achieved its goal: expanding the basis of start-ups. However, it is unclear which factors affect the survival and growth of these new enterprises after their creation. Therefore, this study aims to identify which start-ups from early 2010s survived and which factors influenced their survival and growth. The study will strongly focus on which industries the new enterprises were in, as environmental elements are expected to be critical factors for business of start-ups in Korean context. For this purpose, 105 companies which were introduced as high potential start-ups from 2010 to 2012 were considered in the analysis. According to their current status, dead or alive, the start-ups were categorized by their industries and service area. Through this analysis, it was observed that many start-ups that are still in business are in internet or mobile platform businesses and four major sectors. In each group, a representative case has been studied to reveal its survival and growth factors. The results point to the importance of industrial characteristics for the survival and success of Korean startups and offer political implications in which sector and business more potentials for start-ups in Korea lie in.

Keywords: government support for start-ups, industrial characteristics, Korean start-ups, survival of start-ups

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Authors: Kirstie Smith

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This paper elucidates the value of neighborhood perception as it contributes to the advancement of well-being for individuals and families within a neighborhood. Through in-depth interviews with city residents, this paper examines the degree to which key stakeholders’ (residents) evaluate their neighborhood and perception of resources and identify, access, and utilize local assets existing in the community. Additionally, the research objective included conducting a community inventory that qualified the community assets and resources of lower-income neighborhoods of a medium-sized industrial city. Analysis of the community’s assets was compared with the interview results to allow for a better understanding of the community’s condition. Community mapping revealed the key informants’ reflections of assets were somewhat validated. In each neighborhood, there were more assets mapped than reported in the interviews. Another chief supposition drawn from this study was the identification of key development partners and social networks that offer the potential to facilitate locally-driven community development. Overall, the participants provided invaluable local knowledge of the perception of neighborhood assets, the well-being of residents, the condition of the community, and suggestions for responding to the challenges of the entire community in order to mobilize the present assets and networks.

Keywords: community mapping, family, resource allocation, social networks

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Authors: Azzedine Hamza, Chouaib Chakour, Messaoud Ramdani

Abstract:

Energy demand prediction plays a crucial role in achieving next-generation power systems for agricultural greenhouses. As a result, high prediction quality is required for efficient smart grid management and therefore low-cost energy consumption. The aim of this paper is to investigate the effectiveness of a hybrid data-driven model in day-ahead energy demand prediction. The proposed model consists of Discrete Wavelet Transform (DWT), and Adaptive Neuro-Fuzzy Inference System (ANFIS). The DWT is employed to decompose the original signal in a set of subseries and then an ANFIS is used to generate the forecast for each subseries. The proposed hybrid method (DWT-ANFIS) was evaluated using a greenhouse energy demand data for a week and compared with ANFIS. The performances of the different models were evaluated by comparing the corresponding values of Mean Absolute Percentage Error (MAPE). It was demonstrated that discret wavelet transform can improve agricultural greenhouse energy demand modeling.

Keywords: wavelet transform, ANFIS, energy consumption prediction, greenhouse

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Authors: Fdhila Walid, Bayar Sihem, Khouidi Bochra, Maâtouk Fethi, Ben Amor Feten, Hajer Hentati, Mahdhi Abdelkarim

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The presence of resistant bacteria in the oral cavity can be the major cause of dental antibiotic prophylaxis failure. Multidrug efflux has been described for many organisms, including bacteria and fungi as part of their drugs resistance strategy. The potential use of probiotic bacteria can be considered as a new alternative in the prevention or cure of oral cavity diseases. In this study, different Bacillus strains isolated from the environment were isolated and characterized using biochemical and molecular procedures. The inhibitory activity against different pathogenic bacteria and yeast strains was tested using diffusion agar assay method. Our data revealed that the tested strains have an antimicrobial effect against the pathogenic strains such as Streptococcus mutants. The inhibitory effect was variable depending from the probiotic and pathogenic strains. The obtained result demonstrated that Bacillus can be used as a potential candidates probiotic and help in the prevention and treatment of oral infections, including dental caries, periodontal disease and halitosis. Our data, partly encourage the use of probiotic strains because they do not produce acid which can contribute to faster installation decay and these are spore-forming bacteria that can withstand the stress of the oral cavity (acids, alkalis, and salty foods).

Keywords: probiotic, pathogenic bacteria, yeast, oral cavity

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Authors: Suleh Yusufu Godi, Ado Makama Adamu

Abstract:

Marketing involves all the legal, physical, and economic services which are necessary in moving products from producer to consumers. The more efficient the marketing functions are performed the better the marketing system for the farmers, marketing agents, and the society at large. Rice marketing ensures the flow of product from producers to consumers in the form, time and place of need. Therefore, this study examined profitability of milled rice marketing in Gombe metropolis, Gombe State. Data were collected using structured questionnaires from ninety randomly selected rice marketers in Gombe metropolis. The data were analyzed using descriptive statistics, farm budget technique and regression analysis. The study revealed the total rice marketing cost incurred by rice marketers to be N6, 610,214.70. This gave an average of N73, 446.83 per marketer and N37.30 per Kilogram of rice. The Gross Income for rice marketers in Gombe metropolis was N15, 064,600.00. This value gave an average of N167, 384.44 per rice marketer or N85.00 per kilogram of rice. The study also revealed net income for all rice marketers to be N8, 454,385.30. This gave an average of N93, 937.61 per rice marketer or N47.70 per Kilogram of rice. The study further revealed a marketing margin, marketing efficiency and return per naira invested on rice marketing to be 39.30%, 150.16% and N0.56, respectively. The result of regression analysis shows that age, sex and cost of transportation are positive and significantly affect marketing margin of rice marketers in Gombe Metropolis. However, the main constraints to rice marketing in Gombe metropolis include inadequate electricity, capital, high transportation cost, instability of prices and low patronage among others. The study recommends provision of adequate electrical power supply in the State especially the State capital and also encouraging rice marketers in Gombe metropolis to form cooperative societies so as to have easy access to credit facilities especially from the formal sources.

Keywords: rice marketers, milled rice, cost and return, marketing margin, efficiency, profitability

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Authors: Oktira Roka Aji, Maelita R. Moeis, Ihsanawati, Ernawati A. Giri-Rachman

Abstract:

Globally, tuberculosis (TB) remains a leading cause of death. The emergence of multidrug-resistant strains and extensively drug-resistant strains have become a major public concern. One of the potential candidates for drug target is the cytoplasmic domain of PhoR Histidine Kinase, a part of the Two Component System (TCS) PhoR-PhoP in Mycobacterium tuberculosis (Mtb). TCS PhoR-PhoP relay extracellular signal to control the expression of 114 virulent associated genes in Mtb. The 3D structure of PhoR cytoplasmic domain is needed to screen novel drugs using structure based drug discovery. The PhoR cytoplasmic domain from Mtb H37Rv was overexpressed in E. coli BL21(DE3), then purified using IMAC Ni-NTA Agarose his-tag affinity column and DEAE-ion exchange column chromatography. The molecular weight of the purified protein was estimated to be 37 kDa after SDS-PAGE analysis. This sample was used for pre-crystallization screening by applying sitting drop vapor diffusion method using Natrix (HR2-116) 48 solutions crystal screen kit at 25ºC. Needle-like crystals were observed after the seventh day of incubation in test solution No.47 (0.1 M KCl, 0.01 M MgCl2.6H2O, 0.05 M Tris-Cl pH 8.5, 30% v/v PEG 4000). Further testing is required for confirming the crystal.

Keywords: tuberculosis, two component system, histidine kinase, needle-like crystals

Procedia PDF Downloads 431