Search results for: light weight encryption

Authors: Jyoti Bharj, Sarabjit Singh, Subhash Chander, Rabinder Singh

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The outstanding mechanical properties of Carbon Nanotubes (CNTs) have generated great interest for their potential as reinforcements in high performance cementitious composites. The main challenge in research is the proper dispersion of carbon nanotubes in the cement matrix. The present work discusses the role of dispersion of Multiwall Carbon Nanotubes (MWCNTs) on the compressive strength characteristics of hydrated Portland IS 1489 cement paste. Cement-MWCNT composites with different mixing techniques were prepared by adding 0.2% (by weight) of MWCNTs to Portland IS 1489 cement. Rectangle specimens of size approximately 40mm × 40mm ×160mm were prepared and curing of samples was done for 7, 14, 28, and 35 days. An appreciable increase in compressive strength with both techniques; mixture of MWCNTs with cement in powder form and mixture of MWCNTs with cement in hydrated form 7 to 28 days of curing time for all the samples was observed.

Keywords: carbon nanotubes, Portland cement, composite, compressive strength

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Authors: Junichiro Kawaguchi

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Space debris problems have emerged and threatened the use of low earth orbit around the Earth owing to a large number of spacecraft. In debris removal, a number of research and patents have been proposed and published so far. They assume servicing spacecraft, robots to be built for accessing the target debris objects. The robots should be sophisticated enough automatically to access the debris articulating the attitude and the translation motion with respect to the debris. This paper presents the idea of using the torpedo-like third unsophisticated and disposable body, in addition to the first body of the servicing robot and the second body of the target debris. The third body is launched from the first body from a distance farer than the size of the second body. This paper presents the method and the system, so that the third body is launched from the first body. The third body carries both a net and an inflatable or extendible drag deceleration device and is built small and light. This method enables even a micro to nano satellite to perform contactless and multiple debris removal even via a single flight.

Keywords: ballute, debris removal, echo satellite, gossamer, gun-net, inflatable space structure, small satellite, un-cooperated target

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Authors: Yared Assefa Demessie

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This study may help to establish the appropriateness of ceramic waste aggregate for concrete production since it is obviously understood that the rising from continuous urbanization and industrialization development leads depletion of natural construction resource and the disposal of waste material. It can be used as base to conduct a study on the alternative readily available materials like ceramic industrial waste aggregates can lead to environmental concrete. The study assessed the fresh and hardened properties of the concrete produced by replacing part of the natural fine aggregate with an aggregate produced from ceramic industrial waste. In the study, experimental investigation was employed which involved two major tasks: material specifications and experimental evaluation of concrete were done in the laboratory. Experimental investigations such that workability, unit weight, compressive strength test, tensile strength test and flexural strength test for C-25 concrete mixes with different percentages of ceramic industrial waste aggregate after a curing period of 7 and 28 days has done and interpreted the result statically using mean, standard deviation and coefficient of variance.

Keywords: ceramic industrial waste, fresh concrete, hardened concrete, fine aggregate

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Authors: Fatiha Naaoui-Outini

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Purpose – The purpose of this paper is to shed light on how a Downstream Supply Chain facilitated the Customer Service Performance (BTB) by more collaborative practices between the different stakeholders in the chain. Methodology/approach – The paper developed a theoretical framework and conducted a qualitative exploratory study approach based on six semi-structured interviews with two international groups in the distribution sector with the aim of understanding and analyzing how companies have changed their supply chains to ensure optimal customer service. Findings/Implications – The study contributes to the Global Supply Chain Management and Collaboration literature by integrating the role of the downstream supply chain into research that may actually influence customer service performance on BTB. Our findings also provide firms with some guidelines on building successful downstream supply chain collaboration and a significant influence on customer service performance in BTB. Because of the exploratory nature of the study approach, the research results are limited to the data collected, and these preliminary findings require further confirmation.

Keywords: customer service performance (B2B), global supply chain, downstream supply collaboration, qualitative case study

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Authors: Tamene Keneni, Tibebu Yohannes

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The prevalence of autism spectrum disorder (ASD) in general and autism in particular is on the rise globally, and the need for evidence-based intervention and care for children with autism has grown, too. However, evidence on autism is scanty in developing countries, including Ethiopia. With the aim to help fill the gap and paucity in research into the issue, the main purpose of this study is to explore, better understand, and document the experiences and perceptions of parents of children with autism. To this end, we used a qualitative survey to collect data from a convenient sample of parents raising a child with autism. The data collected were subjected to qualitative analysis that yielded several themes and subthemes, including late diagnosis, parents’ reactions to diagnosis, sources of information during and after diagnosis, differing reactions to having a child with autism from siblings, extended family members, and the larger community, attribution of autism to several causes by the community, lack of recognition and open discussion of autism and lack of appropriated public educational and health care services for children with autism and their parents. The themes and subthemes identified were discussed in light of existing literature, and implications for practice were drawn.

Keywords: ASD, autism, children with autism, raising children with autism

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Authors: Sanaa AM Elgayar, Sohair A Eltony, Maha Mahmoud Abd El Rouf

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Background: Retinopathy remains an important complication of diabetes. Aim of work: This work was carried out to evaluate the protective effects of genistein from diabetic retinopathy in rat. Material and Methods: Fifteen adult male albino rats were divided into two groups; Group I: control (n=5) and Group II: streptozotocin induced diabetic group (n=10), which is equally divided into two subgroups; IIa (diabetic vehicle control) and IIb (diabetic genistein-treated). Specimens were taken from the retina 12 weeks post induction, processed and examined using light, immunohistochemical, ultrastructural techniques. Blood samples were assayed for the levels of glucose. Results: In comparison with the diabetic non-treated group, the histological changes in macro and microglial glial cells reactivity and retinal blood capillaries were improved in genistein-treated groups. In addition, GFAP and iNOS expressions in the retina and the blood glucose level were reduced. Conclusion: Genistein ameliorates the histological changes of diabetic retinopathy reaching healing features, which resemble that of a normal retina.

Keywords: diabetic retinopathy, genistein, glia, capillaries.

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Authors: Taher Eid Shaaban Ahmed Mousa

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Non-Alcoholic fatty liver disease (NAFLD) is a major cause of multiple liver disorders, which strongly linked to a poor lifestyle. This study aiming to elucidate the exercise program’s effectiveness on hepatic fat mobilization among nonalcoholic fatty liver patients. Subjects: A purposive sample of 150 adult male & female patients. Setting: National institute of liver out patient's clinics of Menoufia University. Tools: three tools I: An interviewing structured questionnaire, II: International Physical Activity Questionnaire, III: compliance assessment sheet. Results: There was statistically significant difference pre and post exercise program regarding total body weight, physical activity level and compliance that prevent new fat development with resolution of existing one. Conclusion: regular exercise is the best implemented approach as an initial step for the prevention, treatment and management of NAFLD. Recommendation: It is highly important to unravel the mechanism and dose by which each exercise specifically resolve various stages of liver diseases.

Keywords: exercise program, hebatic fat mobilization, nonalcoholic fatty liver patients, sport science

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Authors: Zafer Ceylan, Gülgün F.Unal Şengör, Onur Gönülal

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In this study, sous vide technology were treated with different herbs into different fish species which were caught from northern Aegean and Marmara Sea. Before samples were packaged under vacuum, herbs had been cut and added at the same ratio into the package. Samples were sliced, the weight of each sample was about 150 g, and packaged under vacuum. During the storage period at 4ºC, taste, odor, texture properties of fish samples treated with sous vide were evaluated by trained panelists. Meanwhile, the effect of different herbs on pH values of the samples was investigated. These results were correlated with sensorial results. Furthermore, the effects of different herbs on L, a, b values of fish samples treated with sous vide were evaluated by color measurement. All sensorial results indicated that the values of samples treated with herbs were higher than that of the control group. Color measurement results and pH values were found parallel with sensorial results.

Keywords: Sous vide, fish, herbs, consumer preferences, pH, color measurement

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Authors: Malek Y. S. Ibrahim, Jeffrey A. Bennett, Milad Abolhasani

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Despite the potential of hydrogen (H2) storage in liquid organic carriers to achieve carbon neutrality, the energy required for H2 release and the cost of catalyst recycling has hindered its large-scale adoption. In response, a photo flow reactor packed with rhodium (Rh)/titania (TiO2) photocatalyst was reported for the continuous and selective acceptorless dehydrogenation of 1,2,3,4-tetrahydroquinoline to H2 gas and quinoline under visible light irradiation at room temperature. The tradeoff between the reactor pressure drop and its photocatalytic surface area was resolved by selective in-situ photodeposition of Rh in the photo flow reactor post-packing on the outer surface of the TiO2 microparticles available to photon flux, thereby reducing the optimal Rh loading by 10 times compared to a batch reactor, while facilitating catalyst reuse and regeneration. An example of using quinoline as a hydrogen acceptor to lower the energy of the hydrogen production step was demonstrated via the water-gas shift reaction.

Keywords: hydrogen storage, flow chemistry, photocatalysis, solar hydrogen

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Authors: L. Chetibi, D. Hamana, T. O. Busko, M. P. Kulish, S. Achour

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TiO2 nanostructures have attracted much attention due to their optical, dielectric and photocatalytic properties as well as applications including optical coating, photocatalysis and photoelectrochemical solar cells. This work aims to prepare TiO2 nanofibers (NFs) on titanium substrate (Ti) by in situ oxidation of Ti foils in a mixture solution of concentrated H2O2 and NaOH followed by proton exchange and calcinations. Scanning Electron microscopy (SEM) revealed an obvious network of TiO2 nanofibers. The photoluminescence (PL) spectra of these nanostructures revealed a broad intense band in the visible light range with a reduced near edge band emission. The PL bands in the visible region, mainly, results from surface oxygen vacancies and others defects. After irradiation with Ti+ ions (the irradiation energy was E = 140 keV with doses of 1013 ions/cm2), the intensity of the PL spectrum decreased as a consequence of the radiation treatment. The irradiation with Ti+ leads to a reduction of defects and generation of non irradiative defects near to the level of the conduction band as evidenced by the PL results. On the other hand, reducing the surface defects on TiO2 nanostructures may improve photocatalytic and optoelectronic properties of this nanostructure.

Keywords: TiO2, nanofibers, photoluminescence, irradiation

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Authors: Mohammad Arif Khan

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This paper analyzes and presents the development of Artificial Neural Network based controller of space vector modulation (ANN-SVPWM) for a seven-phase voltage source inverter. At first, the conventional method of producing sinusoidal output voltage by utilizing six active and one zero space vectors are used to synthesize the input reference, is elaborated and then new PWM scheme called Artificial Neural Network Based PWM is presented. The ANN based controller has the advantage of the very fast implementation and analyzing the algorithms and avoids the direct computation of trigonometric and non-linear functions. The ANN controller uses the individual training strategy with the fixed weight and supervised models. A computer simulation program has been developed using Matlab/Simulink together with the neural network toolbox for training the ANN-controller. A comparison of the proposed scheme with the conventional scheme is presented based on various performance indices. Extensive Simulation results are provided to validate the findings.

Keywords: space vector PWM, total harmonic distortion, seven-phase, voltage source inverter, multi-phase, artificial neural network

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Authors: Wanghongshu Zhou

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This study aims to explore the relationship between the L2MSS and WTC among Chinese non-English major students in order to provide pedagogical implications for English as a Foreign Language (EFL) classrooms in Chinese universities. By employing a mixed methods approach, we involved 103 Chinese non-English major students from a typical university in China, conducted questionnaire survey to measure their levels of L2WTC and L2MSS level, and then analyzed the correlation between the two above mentioned variables. Semi-structured interviews were conducted with eight participants to provide a deeper understanding and explanation of the questionnaire data. Findings show that 1) Chinese non-English major students’ ideal L2 self and L2 learning experience could positively predict their L2 WTC in EFL class; 2) Chinese non-English major students’ ought-to L2 self might have no significant impact on their L2 WTC in EFL class; and 3) self-confidence might be another main factor that will influence Chinese non-English major students’ L2 WTC in EFL class. These findings might shed light on the second language acquisition field and provide pedagogical recommendations for pre-service as well as in-service EFL teachers.

Keywords: L2 willingness to communicate, L2 motivation, self-confidence, Chinese non-English major students

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Authors: Mahmoud Rabh

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Garnet has been used for decades as an abrasive in water jet cutting and sand blasting because of its superior physical properties. When added to use in water-cutting process of marble. A standard commercial sample of the mineral was tested in terms of the hardness and abrasiveness properties. The sample was sized to 4 fractions having the size of < 60 um, > 60 < 100 um, > 100 < 180 um > 1280 < 250 and 250 um designated the symbols, FF, MF, MC and C respectively. Each sample was separately heated in controlled conditions at temperatures up to 1000 °C at a heating rate of 10°C/min in an electrically heated chamber furnace. Soaking time at the maximum temperature was up to 6 h. Hardness and abrasiveness properties of the heat treated samples were tested to cut marble having a thickness of 25 mm. Results revealed that H/A of the natural garnet mineral increased by heating at temperatures up to 600°C and exhibited pronounced decrease with higher temperatures up to 1000 °C. Results were explained in the light of a structural irreversible dislocation (SD) of the crystals of garnet almandine Fe2+3Al2Si3O12 and pyrope Mg3Al2Si3O12. Characterization of the mineral was carried out with the help of XRD, SEM and FT-IR measurements.

Keywords: garnet abrasive, heat treatment, water jet cutting, hardness abrasiveness

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Authors: Cemre Polat, Mustafa Soyler, Bulent Yaniktepe, Coskun Ozalp

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In this study, it was aimed to control the flow actively by giving an oscillating rotational motion to a vertically placed cylinder, and flow characteristics were determined. In the study, firstly, the flow structure around the flat cylinder was investigated with dye experiments, and then the cylinders with different oscillation angles (θ = 60°, θ = 120°, and θ = 180°) and different rotation speeds (15 rpm and 30 rpm) the flow structure around it was examined. Thus, the effectiveness of oscillation and rotation speed in flow control has been investigated. In the dye experiments, the dye/water mixture obtained by mixing Rhodamine 6G in powder form with water, which shines under laser light and allows detailed observation of the flow structure, was used. During the experiments, the dye was injected into the flow with the help of a thin needle at a distance that would not affect the flow from the front of the cylinder. In dye experiments, 100 frames per second were taken with a Canon brand EOS M50 (24MP) digital mirrorless camera at a resolution of 1280 * 720 pixels. Then, the images taken were analyzed, and the pictures representing the flow structure for each experiment were obtained. As a result of the study, it was observed that no separation points were formed at 180° swing angle at 15 rpm speed, 120° and 180° swing angle at 30 rpm, and the flow was controlled according to the fixed cylinder.

Keywords: active flow control, cylinder, flow visualization rotationally oscillating

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Authors: Bok Yae Chung, Eun Hee Oh

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Breast cancer patients require more nutritional interventions than others. However, a few studies have attempted to assess the overall nutritional status, to reduce body weight and BMI by improving diet, and to improve the prognosis of cancer for breast cancer patients. The purpose of this study was to evaluate the effect of diet intervention in the breast cancer patients through meta-analysis. For the study purpose, 16 studies were selected by using PubMed, ScienceDirect, ProQuest and CINAHL. Meta-analysis was performed using a random-effects model, and the effect size on outcome variables in breast cancer was calculated. The effect size for outcome variables of diet intervention was a large effect size. For heterogeneity, moderator analysis was performed using intervention type and intervention duration. All moderators did not significant difference. Diet intervention has significant positive effects on outcome variables in breast cancer. As a result, it is suggested that the timing of the intervention should be no more than six months, but a strategy for sustaining long-term intervention effects should be added if nutritional intervention is to be administered for breast cancer patients in the future.

Keywords: breast cancer, diet, mete-analysis, intervention

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Authors: Zylfi Shehu, Rozeta Shatku

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The aim of this study is the identification of the goods and the consequences it brings up the mountain climbing to the youth, how mountain climbing influences in physical activity and the health of young people. Taken to study 37 young people aged 18-30 years, 25 males and 12 females. The selection was made at random and voluntary. Subjects were not professionals but amateurs climbing in the mountain. They were informed and instructed for the test to be carried out. The ascent was made in January 2016 in the Mount of Gjallica in Kukës, Albania, the height of the mountain is 2489 m above sea level. Backpack for each subject weighing 32 kg. Time of ascent, attitude and descent was 6 days. In 22 males, 2 of them did not afford the ascent on the first day and went back. Of the 12 women, 5 of them withdrew on the first day. During the descent on day six, 20 males 7 of them had minor injuries, three with serious injuries. While a total of 7 women, 4 of them had minor injuries and one with serious injuries. Most of the men and women who deal with physical activity throughout life faced the light and were not injured, and the rest that were not dealt with physical activity were more injured. Lack of experience and knowledge was one of the causes of injuries. The subjects had anxiety all the time, uncertainty and fear of avalanches of snow and difficult terrain.

Keywords: climbing, physical activity, young people

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Authors: Munnujahan Ara

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In this paper, we investigate the effect of friendly jamming power allocation strategies on the achievable average secrecy rate over a bank of parallel fading wiretap channels. We investigate the achievable average secrecy rate in parallel fading wiretap channels subject to Rayleigh and Rician fading. The achievable average secrecy rate, due to the presence of a line-of-sight component in the jammer channel is also evaluated. Moreover, we study the detrimental effect of correlation across the parallel sub-channels, and evaluate the corresponding decrease in the achievable average secrecy rate for the various fading configurations. We also investigate the tradeoff between the transmission power and the jamming power for a fixed total power budget. Our results, which are applicable to current orthogonal frequency division multiplexing (OFDM) communications systems, shed further light on the achievable average secrecy rates over a bank of parallel fading channels in the presence of friendly jammers.

Keywords: fading parallel channels, wire-tap channel, OFDM, secrecy capacity, power allocation

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Authors: Kumaresh Selvakumar, Man Young Kim

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Catalytic combustor substantially reduces emission entailing fuel-air premixing at very low equivalence ratios. The catalytic combustion of natural gas has the potential to become sufficiently active at light off temperature by the convection of heat from the catalyst surface. Only one channel is selected to investigate both the gas and surface reactions in the catalyst bed because of the honeycomb structure of the catalytic combustor. The objective of the present study is to find the methane catalytic combustion behavior inside the catalytic combustor, where the gas phase kinetics is employed by homogeneous methane combustion and surface chemistry is described with the heterogeneous catalysis of the oxidation of methane on a platinum catalyst. The reaction of the premixed mixture in the catalytic regime improves flame stability with complete combustion for lower operating flame temperature. An overview of the flow behavior is presented inside the single channel catalytic combustor including the operation of catalytic combustion with various F/A ratios and premixed inlet temperature.

Keywords: catalytic combustor, equivalence ratios, flame temperature, heterogeneous catalysis, homogeneous combustion

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Authors: M. Rose Ntsewa, P. E. Dlamini, V. E. Mbanjwa, R. Chauke

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Land-use change from undisturbed forest to tea plantation may lead to accumulation or loss of soil organic carbon (SOC). So far, the factors controlling the vertical distribution of SOC under the long-term establishment of tea plantation remain poorly understood, especially in oxisols. In this study, we quantified the vertical distribution of SOC under tea plantation compared to adjacent undisturbed forest Oxisols sited at different topographic positions and also determined controlling edaphic factors. SOC was greater in the 30-year-old tea plantation compared to undisturbed forest oxisols and declined with depth across all topographic positions. Most of the SOC was found in the downslope position due to erosion and deposition. In the topsoil, SOC was positively correlated with heavy metals; manganese (r=0.62-0.83; P<0.05) and copper (r=0.45-0.69), effective cation exchange capacity (ECEC) (r=0.72) and mean weight diameter (MWD) (r=0.72-0.73), while in the subsoil SOC was positively correlated with copper (r=0.89-0.92) and zinc (r=0.86), ECEC (r=0.56-0.69) and MWD (r=0.48). These relationships suggest that SOC in the tea plantation, oxisols is chemically stabilized via complexation with heavy metals, and physically stabilized by soil aggregates.

Keywords: oxisols, tea plantation, topography, undisturbed forest

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Authors: Djoudi Ali

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In this article, we shall expose some of the more interesting interactions of philosophy and cybernetics, some philosophical issues arising in cybernetic systems, and some questions in philosophy of our daily life related to the artificial intelligence. Many of these are fruitfully explored in the article..This article will shed light also on the importance of science and technology in our life and what are the main problems of misusing the latest technologies known under artificial intelligence and cybernatics acoording to Bertrand Russell’s point of view; then to analyse his project of reforms inculding science progress risks , the article show also the whole aspect of the impact of technology on peace , nature and on individual daily behavior, we shall discuss all issues and defies imposing by this new era , The article will invest in showing what Russell will suggest to eliminate or to slow down the dangers of these changes and what are the main solutions to protect the indiviual’s rights and responsiblities In this article, We followed a different methodology, like analysis method and sometimes the historical or descriptive method, without forgetting criticizing some conclusions when it is logically needed In the end, we mentioned what is supposed to be solutions suggested by Bertrand Russell that should be taken into considerations during the next decades and how to protect our ennvironement and the human being of any risk of disappearing

Keywords: artificial intelligence, technology, cybernetics, sience

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Authors: Rini Jarial, Puranjan Mishra, Lakhveer Singh, Sveta Thakur, A. W. Zularisam, Mimi Sakinah

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The aim of the present study was to assess the biological properties of Camellia sinensis and to identify its functional compounds. The methanolic leaves-extract (MLE) of commercial green tea (Camellia sinensis) was assessed for anti-bacterial activities by measuring inhibition zones against a panel of pathogenic bacterial strains using agar diffusion method. The flavonoid (5.0 to 8.0 mg/ml) and protein content (10 to 15 mg/ml) of the MLE were recorded. MLE at a concentration of 25 μg/ml showed marked anti-bacterial activity against all bacterial strains (11-30 mm zone of inhibition) and was maximum against Staphylococcus aureus (30 mm). The MLE of Camellia sinensis had the best MIC values of 2.25 and 0.56 mg/ml against S. aureus and Enterobacter sp., respectively. The MLE also possessed good anti-lipolytic activity (65%) against a Porcine pancreatic lipase (PPL) and cholesterol oxidase inhibition (79%). The present study provided strong experimental evidences that the MLE of Camellia sinensis is not only a potent source of natural anti-oxidants and anti-bacterial activity but also possesses efficient cholesterol degradation and anti-lipolytic activities that might be beneficial in the body weight management.

Keywords: anti-oxidant, anti-bacterial activity, anti-lipolytic activity, Camellia sinensis, phyto-chemicals

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Authors: H. Ucar, U. Aridogan

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Composite structures become intriguing for the design of aerospace, automotive and marine applications due to weight reduction, corrosion resistance and radar signature reduction demands and requirements. Studies on piezoelectric ceramic transducers (PZT) for diagnostics and health monitoring have gained attention for their sensing capabilities, however PZT structures are prone to fail in case of heavy operational loads. In this paper, we develop a piezo-based Glass Fiber Reinforced Polymer (GFRP) composite finite element (FE) model, validate with experimental setup, and identify the applicability and limitations of PZTs for a marine application. A case study is conducted to assess the piezo-based sensing capabilities in a representative marine composite structure. A FE model of the composite structure combined with PZT patches is developed, afterwards the response and functionality are investigated according to the sea conditions. Results of this study clearly indicate the blockers and critical aspects towards industrialization and wide-range use of PZTs for marine composite applications.

Keywords: FRP composite, operational challenges, piezoelectric transducers, FE modeling

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Authors: Mounir Tichamakdj, Khaled Sandjak, Boualem Tiliouine

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The design of flexible pavements is currently carried out using a multilayer elastic theory. However, for thin-surface pavements subject to light or medium traffic volumes, the importance of the non-linear stress-strain behavior of unbound granular materials requires the use of more sophisticated numerical models for the structural design of these pavements. The simplified analysis of the nonlinear behavior of granular materials in pavement design will be developed in this study. To achieve this objective, an equivalent linear model derived from a volumetric shear stress model is used to simulate the nonlinear elastic behavior of two unlinked local granular materials often used in pavements. This model is included here to adequately incorporate material non-linearity due to stress dependence and stiffness of the granular layers in the flexible pavement analysis. The sensitivity of the pavement design criteria to the likely variations in asphalt layer thickness and the mineralogical nature of unbound granular materials commonly used in pavement structures are also evaluated.

Keywords: granular materials, linear equivalent model, non-linear behavior, pavement design, shear volumetric strain model

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Authors: Siao-Wei Jiang, Boy-Young Hsieh, Ching-Liang Hsieh, Cheng-Yung Lin

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The problems of multiple drug resistance in the pig farming industry have been emphasized in recent years. Diarrhea syndrome is common in weaning piglets and often treated with antibiotics as a feed additive, leading to the rapid spread of antibiotic resistance and posing high health risks to humans. The study aimed to alleviate diarrhea syndrome with traditional herbal medicine, Xiang Sha Liu Jun Zi Tang, whose effects enhanced digestive function. Piglets at 4 weeks old with stool classified to Bristol stool classification type 6 or type 7 were randomly divided into the control group, group A (1% of Xiang Sha Liu Jun Zi Tang) and group B (0.1% Colistin). The piglets were administrated for 7 days, and their weight, feed intake, and stool score were recorded daily before and after the trial. The results showed that the diarrhea index score in group A and group B improved significantly compared to the control group, indicating that Xiang Sha Liu Jun Zi Tang may have the same effect on alleviating diarrhea syndrome as Colistin, and it may be another replacement for antibiotics.

Keywords: pig, diarrhea, herbal medicine, Xiang Sha Liu Jun Zi Tang

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Authors: Francesca Gullo, Paola Palmero, Massimo Messori

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Transparent wood is considered a promising structural material for the development of environmentally friendly, energy-efficient engineered components. To obtain transparent wood from natural wood materials two approaches can be used: i) bottom-up and ii) top-down. Through the second method, the color of natural wood samples is lightened through a chemical bleaching process that acts on chromophore groups of lignin, such as the benzene ring, quinonoid, vinyl, phenolics, and carbonyl groups. These chromophoric units form complex conjugate systems responsible for the brown color of wood. There are two strategies to remove color and increase the whiteness of wood: i) lignin removal and ii) lignin bleaching. In the lignin removal strategy, strong chemicals containing chlorine (chlorine, hypochlorite, and chlorine dioxide) and oxidizers (oxygen, ozone, and peroxide) are used to completely destroy and dissolve the lignin. In lignin bleaching methods, a moderate reductive (hydrosulfite) or oxidative (hydrogen peroxide) is commonly used to alter or remove the groups and chromophore systems of lignin, selectively discoloring the lignin while keeping the macrostructure intact. It is, therefore, essential to manipulate nanostructured wood by precisely controlling the nanopores in the cell walls by monitoring both chemical treatments and process conditions, for instance, the treatment time, the concentration of chemical solutions, the pH value, and the temperature. The elimination of wood light scattering is the second step in the fabrication of transparent wood materials, which can be achieved through two-step approaches: i) the polymer impregnation method and ii) the densification method. For the polymer impregnation method, the wood scaffold is treated with polymers having a corresponding refractive index (e.g., PMMA and epoxy resins) under vacuum to obtain the transparent composite material, which can finally be pressed to align the cellulose fibers and reduce interfacial defects in order to have a finished product with high transmittance (>90%) and excellent light-guiding. However, both the solution-based bleaching and the impregnation processes used to produce transparent wood generally consume large amounts of energy and chemicals, including some toxic or pollutant agents, and are difficult to scale up industrially. Here, we report a method to produce optically transparent wood by modifying the lignin structure with a chemical reaction at room temperature using small amounts of hydrogen peroxide in an alkaline environment. This method preserves the lignin, which results only deconjugated and acts as a binder, providing both a strong wood scaffold and suitable porosity for infiltration of biobased polymers while reducing chemical consumption, the toxicity of the reagents used, polluting waste, petroleum by-products, energy and processing time. The resulting transparent wood demonstrates high transmittance and low thermal conductivity. Through the combination of process efficiency and scalability, the obtained materials are promising candidates for application in the field of construction for modern energy-efficient buildings.

Keywords: bleached wood, energy-efficient components, hydrogen peroxide, transparent wood, wood composites

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Authors: Sabri Gabran Mohammed Elkrghli, Salah A. Mohamed Abdulgader

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Given the emergence and the spreading of the Covid-19 pandemic that swept the globe, it was necessary to address the issue of consumer rights in such unprecedented circumstances. Libyan consumers have been targeted in this study with the aim to measure their attitudes towards the extent to which their rights, as consumers of foodstuff, have been secured during the Covid-19 pandemic. The recommended sample size was randomly selected (384) local participants. Out of this number, only a validated number of (267) responses were deemed valid for the analysis phase. The instrument of this research was developed based on the extant published literature on consumer rights. The study concluded with a set of key results; the most important result is that consumer rights of foodstuffs were below the satisfactory level. Theoretical and practical implications have emerged from the study. The most important implication is that customers of foodstuffs need more protection in Libya. This issue should be given greater importance, especially in the light of contemporary environmental challenges such as the outbreak of Covid-19. Designing and conducting global and local awareness campaigns is another significant advice suggested by this study. Finally, the research concluded with limitations and put forward some future avenues.

Keywords: consumers rights, foodstuffs, COVID-19, Libya

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Authors: Rashad Al Araj, Adil K. Tamimi

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Concrete, despite being one of the most produced materials in the world, still has weaknesses and drawbacks. Significant concern of the cementitious materials in structural applications is their quasi-brittle behavior, which causes the material to crack and lose its durability. One of the very recently proposed mitigations for this problem is the implementation of nanotechnology in the concrete mix by adding carbon nanotubes (CNTs) to it. CNTs can enhance the critical mechanical properties of concrete as a structural material. Thus, this paper demonstrates a state-of-the-art review of reinforcing concrete with CNTs, emphasizing on the structural performance. It also goes over the properties of CNTs alone, the present methods and costs associated with producing them, the possible special applications of concretes reinforced with CNTs, the key challenges and drawbacks that this new technology still encounters, and the most reliable practices and methodologies to produce CNT-reinforced concrete in the lab. This work has shown that the addition of CNTs to the concrete mix in percentages as low as 0.25% weight of cement could increase the flexural strength and toughness of concrete by more than 45% and 25%, respectively, and enhance other durability-related properties, given that an effective dispersion of CNTs in the cementitious mix is achieved. Since nano reinforcement for cementitious materials is a new technology, many challenges have to be tackled before it becomes practiced at the mass level.

Keywords: sustainability, carbon nano tube, microsilica, concrete

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Authors: Mahdi Fakoor, Seyed Mohammad Navid Ghoreishi

Abstract:

Composite patching is a common way for reinforcing the cracked pipes and cylinders. The effects of composite patch reinforcement on fracture parameters of a cracked pipe depend on a variety of parameters such as number of layers, angle, thickness, and material of each layer. Therefore, stacking sequence optimization of composite patch becomes crucial for the applications of cracked pipes. In this study, in order to obtain the optimal stacking sequence for a composite patch that has minimum weight and maximum resistance in propagation of cracks, a coupled Multi-Objective Genetic Algorithm (MOGA) and Finite Element Method (FEM) process is proposed. This optimization process has done for longitudinal and transverse semi-elliptical cracks and optimal stacking sequences and Pareto’s front for each kind of cracks are presented. The proposed algorithm is validated against collected results from the existing literature.

Keywords: multi objective optimization, pareto front, composite patch, cracked pipe

Procedia PDF Downloads 298

Authors: S. Nurdiana, A. S. Nor Haziqah, M. K. Nur Ezwa Khairunnisa, S. Nurul Izzati, Y. Siti Amna M. J. Norashirene, I. Nur Hilwani

Abstract:

Azadirachta excelsa or locally known as sentang are frequently used as a traditional medicine by diabetes patients in Malaysia. However, less attention has been given to their toxicity effect. Thus, the study is an attempt to examine the protective effect of A. excelsa on the pancreas and to determine possible toxicity mediated by the extract. Diabetes was induced experimentally in rats by high-fat-diet for 16 weeks followed by intraperitoneal injection of streptozotocin at dosage of 35 mg/kg of body weight. Declination of the fasting blood glucose level was observed after continuous administration of A. excelsa for 14 days twice daily. This is due to the refining structure of the pancreas. However, surprisingly, the plant extract reduced the leukocytes, erythrocytes, hemoglobin, MCHC and lymphocytes. In addition, the rat treated with the plant extract exhibited increment in AST and eosinocytes level. Overall, the finding shows that A. excelsa possesses antidiabetic activity by improving the structure of pancreatic islet of Langerhans but involved in ameliorating of hematology and biochemical parameters.

Keywords: Azadirachta excelsa, diabetes, pancreas, hemato-biochemical parameters

Procedia PDF Downloads 403

Authors: Manish Kumar, Krupa Shah

Abstract:

The usage of renewable energy sources is increased day by day to overcome the dependency on fossil fuels. The wind energy is considered as a prominent source of renewable energy. This paper presents an approach for utilizing wind energy obtained from moving the vehicle for cell-phone charging. The selection of wind turbine, blades, generator, etc. is done to have the most efficient system. The calculation procedure for power generated and drag force is shown to know the effectiveness of the proposal. The location of the turbine is selected such that the system remains symmetric, stable and has the maximum induced wind. The calculation of the generated power at different velocity is presented. The charging is achieved for the speed 30 km/h and the system works well till 60 km/h. The model proposed seems very useful for the people traveling long distances in the absence of mobile electricity. The model is very economical and easy to fabricate. It has very less weight and area that makes it portable and comfortable to carry along. The practical results are shown by implementing the portable wind turbine system on two-wheeler.

Keywords: cell-phone charging, on-board power generation, wind energy, vehicle

Procedia PDF Downloads 285