Search results for: effect of student activities

Authors: Lazhar Zourgui

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Opuntia species are used as local medicinal interventions for chronic diseases and as food sources, mainly because they possess nutritional properties and biological activities. Opuntia ficus-indica (L.) Mill, commonly known as prickly pear or nopal cactus, is the most economically valuable plant in the Cactaceae family worldwide. It is a tropical or subtropical plant native to tropical and subtropical America, which can grow in arid and semi-arid climates. It belongs to the family of angiosperms dicotyledons Cactaceae of which about 1500 species of cacti are known. The Opuntia plant is distributed throughout the world and has great economic potential. There are differences in the phytochemical composition of Opuntia species between wild and domesticated species and within the same species. It is an interesting source of plant bioactive compounds. Bioactive compounds are compounds with nutritional benefits and are generally classified into phenolic and non-phenolic compounds and pigments. Opuntia species are able to grow in almost all climates, for example, arid, temperate, and tropical climates, and their bioactive compound profiles change depending on the species, cultivar, and climatic conditions. Therefore, there is an opportunity for the discovery of new compounds from different Opuntia cultivars. Health benefits of prickly pear are widely demonstrated: There is ample evidence of the health benefits of consuming prickly pear due to its source of nutrients and vitamins and its antioxidant properties due to its content of bioactive compounds. In addition, prickly pear is used in the treatment of hyperglycemia and high cholesterol levels, and its consumption is linked to a lower incidence of coronary heart disease and certain types of cancer. It may be effective in insulin-independent type 2 diabetes mellitus. Opuntia ficus-Indica seed oil has shown potent antioxidant and prophylactic effects. Industrial applications of these bioactive compounds are increasing. In addition to their application in the pharmaceutical industries, bioactive compounds are used in the food industry for the production of nutraceuticals and new food formulations (juices, drinks, jams, sweeteners). In my lecture, I will review in a comprehensive way the phytochemical, nutritional, and bioactive compound composition of the different aerial and underground parts of Opuntia species. The biological activities and applications of Opuntia compounds are also discussed.

Keywords: medicinal plants, cactus, Opuntia, actives biomolecules, biological activities

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Authors: A. Chellil, A. Nour, S. Lecheb, H.Mechakra, A. Bouderba, H. Kebir

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In this paper, the numerical study for the instability of a composite rotor is presented, under dynamic loading response in the harmonic analysis condition. The analysis of the stress which operates the rotor is done. Calculations of different energies and the virtual work of the aerodynamic loads from the rotor is developed. The use of the composite material for the rotor, offers a good Stability. Numerical calculations on the model develop of three dimensions prove that the damage effect has a negative effect on the stability of the rotor. The study of the composite rotor in transient system allowed to determine the vibratory responses due to various excitations.

Keywords: rotor, composite, damage, finite element, numerical

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Authors: M. B. Sokoto, I. U. Abubakar

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The study was carried out on effect of water stress and variety on growth of wheat (Triticum aestivum L.), during 2009/10 and 2010/11 dry seasons. The treatments consisted of factorial combination of water stress at three critical growth stage which was imposed by withholding water at (Tillering, Flowering, Grain filling) and Control (No stress) and two varieties (Star 11 TR 77173/SLM and Kauze/Weaver) laid out in a split-plot design with three replications. Water stress was assigned to the main-plot while variety was assigned to the sub-plots. Result revealed significant (P<0.05) effect of water stress, water stress at tillering significantly (P<0.05) reduced plant height, LAI, CGR, and NAR. Variety had a significant effect on plant height, LAI, CGR and NAR. In conclusion water stress at tillering was observed to be most critical growth stage in wheat, and water stress at this period should be avoided because it results to decrease in growth components in wheat. Wheat should be sown in November or at least first week of December in this area and other area with similar climate. Star II TR 77173/LM is recommended variety for the area.

Keywords: wheat, growth, water stress, variety, Sudan savannah

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Authors: Djordjevic J. Sladjana, Djordjevic-Milošević B. Suzana, Milošević M. Slobodan

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The potential of biomass as a renewable energy source leads Serbia to be the top of European countries by the amount of available but unused biomass. Technologies for its use are available and ecologically acceptable. Moreover, they are not expensive high-tech solutions even for the poor investment environment of Serbia, while other options seem to be less achievable. From the other point of view, Serbia has a huge percentage of unused agriculture land. Agricultural production in Serbia languishes: a large share of agricultural land therefore remains untreated, and there is a significant proportion of degraded land. From all the above, biomass intended for energy production is becoming an increasingly important factor in the stabilization of agricultural activities. Orientation towards the growing bioenergy crops versus conventional crop cultivation becomes an interesting option. The aim of this paper is to point out the possibility of growing energy crops in accordance with the conditions and cultural practice in rural areas of Serbia. First of all, the cultivation of energy crops on lower quality land is being discussed, in order to revitalize the rural areas of crops through their inclusion into potential energy sector. Next is the theme of throwing more light on the increase in the area under this competitive agricultural production to correct land use in terms of climate change in Serbia. The goal of this paper is to point out the contribution of the share of biomass in energy production and consumption, and the effect of reducing the negative environmental impact.

Keywords: agro-energy crops, conditions for plantation, revitalization of rural areas, degraded and unused soils

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Authors: Shirin Shaideh, Nina Shirkhanloo

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Creative public spaces were needed to foster conviviality in an urban form. The conviviality could be enhanced by facilitating variety of opportunities to participate in communal activities and promoting collective experiences. In this regard, The Namik Kemal Square as a major public space of Walled City of Famagusta in North Cyprus was found as the creative public space because it supports collective practices by leisure activities which enclosed the space. The square also utilized creative collaboration such as festivals and outdoor exhibition. Accordingly this paper focuses on the issue of conviviality in urban public space, in the perspective of square, as a major indicator of their success. The survey firstly provides a theoretical framework for understanding conviviality in creative public space to empower collective experience. Secondly it discusses the essential components of conviviality in form of square and finally investigating conviviality and also its determinants in Namik Kemal square. Hence, the main challenges of this study are going to focus on how convivial public spaces impact collective experience, what people expect from a kind of public space, or what they perceive as a good place to be in. Since it seems essential to respond positively, inclusively to the needs of people to socialize in public spaces by involving them in collective and common practices, this article aims to tease out what gives some places personality and conviviality so that we can learn to design, maintain and manage better quality built environment in future.

Keywords: conviviality, creative public space, collective experience, Namik Kemal square

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Authors: Jeffrey M. Byford

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The conceptualized theory of decision making on historical events often does not conform to uniform beliefs among students. When presented the opportunity, many students have differing opinions and rationales associated with historical events and outcomes. The intent of this paper was to provide students with the economic, social and political dilemmas associated with the autonomy of East Berlin. Students ranked seven possible actions from the most to least acceptable. In addition, students were required to provide both positive and negative factors for each decision and relative ranking. Results from this activity suggested that while most students chose a financial action towards West Berlin, some students had trouble justifying their actions.

Keywords: content-centered learning, cold war, Berlin, decision-making

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Authors: Mohammad Matin

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Nowadays, one of the basic problems of higher education is a significant decline in the quality of education and reduction in efficiency of training. These research and studies are aiming to assess affecting factors of the erosion of academic quality, including educational environmental and content, social and economic factors, elements of the training, elements of education, family factors, from the perspective of students. The result of such improper competition, totally, has led to the decline of education quality in higher education centers, and in many aspects. The results showed a significant difference between male and female students' perspective for two areas of social and economic factors.

Keywords: higher education, decline, the quality of education, student

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Authors: P. Arun Subhash, B. N. Suresh, M. C. Shivakumar, N. Suma

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An experiment was conducted to study the effect of dietary supplementation of ashwagandha (Withania somnifera) root powder on the egg production performance and egg quality in commercial layer birds. A practical type layer diet was prepared as per Bureau of Indian Standards (1992) to serve as the control, and the test diet was prepared by supplementing control diet with ashwagandha powder at 1kg/ton of feed. Each diet was assigned to twenty replicate groups of 5 laying hens each for duration of 84 days. The result revealed that cumulative egg production (%) was comparable between control and test group. The feed consumption and its conversion efficiency were similar among both the groups. The egg weight and egg characteristics viz., yolk index, yolk color, haugh unit score, albumen index, egg shape index and eggshell thickness were also remained similar between both the groups. It was concluded that supplementation of ashwagandha powder at 1kg/ton in layer diets has no beneficial effect on egg production and egg quality parameters.

Keywords: ashwagandha, egg production, egg quality, layers

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Authors: Larry Powell, Seth Polsley, Drew Casey, Tracy Hammond

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Human activity recognition (HAR) systems have shown positive performance when recognizing repetitive activities like walking, running, and sleeping. Water-based activities are a reasonably new area for activity recognition. However, water-based activity recognition has largely focused on supporting the elite and competitive swimming population, which already has amazing coordination and proper form. Beginner swimmers are not perfect, and activity recognition needs to support the individual motions to help beginners. Activity recognition algorithms are traditionally built around short segments of timed sensor data. Using a time window input can cause performance issues in the machine learning model. The window’s size can be too small or large, requiring careful tuning and precise data segmentation. In this work, we present a method that uses a time window as the initial segmentation, then separates the data based on the change in the sensor value. Our system uses a multi-phase segmentation method that pulls all peaks and valleys for each axis of an accelerometer placed on the swimmer’s lower back. This results in high recognition performance using leave-one-subject-out validation on our study with 20 beginner swimmers, with our model optimized from our final dataset resulting in an F-Score of 0.95.

Keywords: time window, peak/valley segmentation, feature extraction, beginner swimming, activity recognition

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Authors: Farhad Aalizadeh, Ali Moosavi

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This paper presents a two-dimensional Computational Fluid Dynamics (CFDs) simulation for the steady, particle tracking. The purpose of this paper is applied magnetic field effect on Magnetic Nanoparticles velocities distribution. It is shown that the permeability of the particles determines the effect of the magnetic field on the deposition of the particles and the deposition of the particles is inversely proportional to the Reynolds number. Using MHD and its property it is possible to control the flow velocity, remove the fouling on the walls and return the system to its original form. we consider a channel 2D geometry and solve for the resulting spatial distribution of particles. According to obtained results when only magnetic fields are applied perpendicular to the flow, local particles velocity is decreased due to the direct effect of the magnetic field return the system to its original fom. In the method first, in order to avoid mixing with blood, the ferromagnetic particles are covered with a gel-like chemical composition and are injected into the blood vessels. Then, a magnetic field source with a specified distance from the vessel is used and the particles are guided to the affected area. This paper presents a two-dimensional Computational Fluid Dynamics (CFDs) simulation for the steady, laminar flow of an incompressible magnetorheological (MR) fluid between two fixed parallel plates in the presence of a uniform magnetic field. The purpose of this study is to develop a numerical tool that is able to simulate MR fluids flow in valve mode and determineB0, applied magnetic field effect on flow velocities and pressure distributions.

Keywords: MHD, channel clots, magnetic nanoparticles, simulations

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Authors: Lauren E. Church

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Background: Extravehicular activities (EVAs) are a critical aspect of missions aboard the International Space Station (ISS). It has long been noted that the spaceflight environment and the physical demands of EVA cause physiological and metabolic changes in humans; this review aims to combine these findings with nutritional studies in analogues of the spaceflight and EVA environments to make nutritional recommendations for astronauts scheduled for and immediately returning from EVAs. Results: Energy demands increase during orbital spaceflight and see further increases during EVA. Another critical element of EVA nutrition is adequate hydration. Orbital EVA appears to provide adequate hydration under current protocol, but during lunar surface EVA (LEVA) and in a 10km lunar walk-back test astronauts have stated that up to 20% more water was needed. Previous attempts for in-suit edible sustenance have not been adequately taken up by astronauts to be economically viable. In elite endurance athletes, a mixture of glucose and fructose is used in gels, improving performance. Discussion: A combination of non-caffeinated energy drink and simple water should be available for astronauts during EVA, allowing more autonomy. There should also be provision of gels or a similar product containing appropriate sodium levels to maintain hydration, but not so much as to hyperhydrate through renal water reabsorption. It is also suggested that short breaks be built into the schedule of EVAs for these gels to be consumed, as it is speculated that reason for low uptake of in-suit sustenance is the lack of time available in which to consume it.

Keywords: astronaut, nutrition, space, sport

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Authors: Zipei Yin

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Community space is the main place for children's daily outdoor activities. The mountain community space has the typical characteristics of a closed natural environment, a scattered population layout with height differences, and a relatively independent group structure. This has resulted in special limitations on children's outdoor activities in terms of safety, accessibility, and appropriateness, which urgently makes it necessary to explore how to construct children's activity spaces in mountainous societies under the special limitations. This study investigated the activity spaces for children aged 3-11 years old in typical old communities in Chongqing and evaluated them based on the dimensions of spatial characteristics, environmental safety, and connectivity to summarise three typical patterns of children's outdoor activity spaces in old communities in mountainous cities. Then, under the framework of the appeal of the child-friendly urban environment, taking advantage of the characteristics of the old community in mountain cities compared with the plain urban community, such as complex social form, diversified functional positioning, and good foundation of autonomy, this paper explores the micro-renewal path and strategy of the compound utilization of community public space from the two levels of design and governance, so as to further promote the research and practice of the healthy development of mountain urban community environment.

Keywords: child-friendly, healthy community, community public space, mountainous urban community, community renewal

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Authors: Patricia Chinyere Oranefo

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This study examined the effect of sustainability accounting disclosure on financial performance of listed Brewery firms in Nigeria. The dearth of empirical evidence and literature on “governance disclosure” as one of the explanatory variables of sustainability accounting reporting were the major motivation for this study. The main objective was to ascertain the effect of sustainability accounting disclosure on financial performance of listed Brewery firms in Nigeria. An ex–post facto research design approach was adopted for the study. The population of this study comprises of five (5) Brewery firms quoted on the floor of the Nigeria exchange group (NSX) and the sample size of four (4) listed firms was drawn using purposive sampling method. Secondary data were carefully sourced from the financial statement/annual reports and sustainability reports from 2012 to 2021 of the Brewery firms quoted on the Nigeria exchange group (NSX). Panel regression analysis by aid of E-views 10.0 software was used to test for statistical significance of the effect of sustainability accounting disclosure on financial performance of listed Brewery firms in Nigeria. The results showed that economic sustainability disclosure indexes do not significantly affect return on asset of listed Brewery firms in Nigeria. The findings further revealed that environmental sustainability disclosure indexes do not significantly affect return on equity of listed Brewery firms in Nigeria. More so, results showed that Social Sustainability disclosure indexes significantly affect Net Profit Margin of listed Brewery firms in Nigeria. Finally, the result established also that governance sustainability disclosure indexes do not significantly affect Earnings per share of listed Brewery firms in Nigeria. Consequent upon the findings, this study recommended among others; that managers of Brewers in Nigeria should improve and sustain full disclosure practices on economic, environmental, social and governance disclosures following the guidelines of the Global Reporting Index (GRI) as they are capable of exerting significant effect on financial performance of firms in Nigeria.

Keywords: sustainability, accounting, disclosure, financial performance

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Authors: Yemane Hailu Fissuh, Zhongzhan Zhang

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In biomedical researches and randomized clinical trials, the most commonly interested outcomes are time-to-event so-called survival data. The importance of robust models in this context is to compare the effect of randomly controlled experimental groups that have a sense of causality. Causal estimation is the scientific concept of comparing the pragmatic effect of treatments conditional to the given covariates rather than assessing the simple association of response and predictors. Hence, the causal effect based semiparametric transformation model was proposed to estimate the effect of treatment with the presence of possibly time-varying covariates. Due to its high flexibility and robustness, the semiparametric transformation model which shall be applied in this paper has been given much more attention for estimation of a causal effect in modeling left-truncated and right censored survival data. Despite its wide applications and popularity in estimating unknown parameters, the maximum likelihood estimation technique is quite complex and burdensome in estimating unknown parameters and unspecified transformation function in the presence of possibly time-varying covariates. Thus, to ease the complexity we proposed the modified estimating equations. After intuitive estimation procedures, the consistency and asymptotic properties of the estimators were derived and the characteristics of the estimators in the finite sample performance of the proposed model were illustrated via simulation studies and Stanford heart transplant real data example. To sum up the study, the bias of covariates was adjusted via estimating the density function for truncation variable which was also incorporated in the model as a covariate in order to relax the independence assumption of failure time and truncation time. Moreover, the expectation-maximization (EM) algorithm was described for the estimation of iterative unknown parameters and unspecified transformation function. In addition, the causal effect was derived by the ratio of the cumulative hazard function of active and passive experiments after adjusting for bias raised in the model due to the truncation variable.

Keywords: causal estimation, EM algorithm, semiparametric transformation models, time-to-event outcomes, time-varying covariate

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Authors: Hounyèmè Romuald, Maxime Logez, Mama Daouda, Argillier Christine

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In view of the very strong degradation of aquatic ecosystems, it is urgent to set up monitoring systems that are best able to report on the effects of the stresses they undergo. This is particularly true in developing countries, where specific and relevant quality standards and funding for monitoring programs are lacking. The objective of this study was to make a relevant and objective choice of physicochemical parameters informative of the main stressors occurring on African lakes and to identify their alteration thresholds. Based on statistical analyses of the relationship between several driving forces and the physicochemical parameters of the Nokoué lagoon, relevant Physico-chemical parameters were selected for its monitoring. An innovative method based on Bayesian statistical modeling was used. Eleven Physico-chemical parameters were selected for their response to at least one stressor and their threshold quality standards were also established: Total Phosphorus (<4.5mg/L), Orthophosphates (<0.2mg/L), Nitrates (<0.5 mg/L), TKN (<1.85 mg/L), Dry Organic Matter (<5 mg/L), Dissolved Oxygen (>4 mg/L), BOD (<11.6 mg/L), Salinity (7.6 .), Water Temperature (<28.7 °C), pH (>6.2), and Transparency (>0.9 m). According to the System for the Evaluation of Coastal Water Quality, these thresholds correspond to” good to medium” suitability classes, except for total phosphorus. One of the original features of this study is the use of the bounds of the credibility interval of the fixed-effect coefficients as local weathering standards for the characterization of the Physico-chemical status of this anthropized African ecosystem.

Keywords: driving forces, alteration thresholds, acadjas, monitoring, modeling, human activities

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Authors: Seedwell Sithole

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One of the persistent problems in accounting education is how to effectively support students’ learning. A promising technique to this issue is to investigate the extent that learning is determined by the design of instructional material. This study examines the academic performance of students using three instructional designs in financial accounting. Student’s performance scores and reported mental effort ratings were used to determine the instructional effectiveness. The findings of this study show that accounting students prefer graph and text designs that are integrated. The results suggest that spatially separated graph and text presentations in accounting should be reorganized to align with the requirements of human cognitive architecture.

Keywords: accounting, cognitive load, education, instructional preferences, students

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Authors: Suvankar Chakraborty

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Introduction: Corporate Social Responsibility means the obligations of business to act in a manner which will serve the best interests of the Society. The Companies Act , 2013 for the first time has emphasized on the fact that every company having net worth of rupees five hundred crore or more, or turnover of rupees one thousand crore or more or a net profit of rupees five crore or more during any financial year shall constitute a Corporate Social Responsibility Committee of the Board consisting of three or more directors, out of which at least one director shall be an independent director. In the previous Companies Act, 1956 there was no such compulsion for constituting a Corporate Social Responsibility Committee. Objective: This study examines the changes in the perception of corporate sectors so far as social responsibility is concerned. Methodology: The study is based on secondary data obtained from various websites of different corporate sectors and the Gazette of India related to Companies Act, 1956 and the new Companies Act, 2013. For capturing the perception of the corporate world regarding the provisions of CSR in the new Companies Act, 2013, primary data has been collected through structured questionnaire. Findings: Corporate Social Responsibility can put a company on a strong base of sustainable development and in facing the business risk of foreclosure or winding up. Shouldering social responsibility on a long-term basis can help a company not only in increasing its reputation in the business world but also helps in minimizing Government intervention. . But, there can hardly be any universal rule that the area of social responsibility being wholly and solely dependent on the ethical aspect of the corporate sectors. But having said that it may be asserted that business ethics may be a key driver of CSR activities rather than rule based CSR activities in the years to come.

Keywords: business ethics, corporate social responsibility, companies act, 2013, CSR committee

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Authors: Deeman Yousif Mahmood, Mohammed Abdullah Hussein

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The goal of a network-based intrusion detection system is to classify activities of network traffics into two major categories: normal and attack (intrusive) activities. Nowadays, data mining and machine learning plays an important role in many sciences; including intrusion detection system (IDS) using both supervised and unsupervised techniques. However, one of the essential steps of data mining is feature selection that helps in improving the efficiency, performance and prediction rate of proposed approach. This paper applies unsupervised K-means clustering algorithm with information gain (IG) for feature selection and reduction to build a network intrusion detection system. For our experimental analysis, we have used the new NSL-KDD dataset, which is a modified dataset for KDDCup 1999 intrusion detection benchmark dataset. With a split of 60.0% for the training set and the remainder for the testing set, a 2 class classifications have been implemented (Normal, Attack). Weka framework which is a java based open source software consists of a collection of machine learning algorithms for data mining tasks has been used in the testing process. The experimental results show that the proposed approach is very accurate with low false positive rate and high true positive rate and it takes less learning time in comparison with using the full features of the dataset with the same algorithm.

Keywords: information gain (IG), intrusion detection system (IDS), k-means clustering, Weka

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Authors: Banu Ozturk Kurtaslan, Ruhugul Ozge Ocak

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In this study, educational problems related to landscape design education which is an important study area of landscape architecture discipline. It is important to research about the problems in S.U. Agriculture Faculty Landscape Architecture Department which is a new department, started its B.Sc. education in 2011; and developing some suggestions on this issue in terms of future of the department. In the context of the study a questionnaire has been developed to conduct to the B.Sc. students. The questions has been prepared under the topics of education program, instructor, student, physical infrastructure and other problems.

Keywords: landscape design, landscape design education, problems, Selcuk University Landscape Architecture Department

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Authors: Mogens Saberi

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The following article focuses on a new seismic design approach for Denmark. Denmark is located in a low seismic zone and up till now a general and very simplified approach has been used to accommodate the effect of seismic loading. The current used method is presented and it is found that the approach is on the unsafe side for many building types in Denmark. The damages during time due to earth quake is presented and a seismic map for Denmark is developed and presented. Furthermore, a new design approach is suggested and compared to the existing one. The new approach is relatively simple but captures the effect of seismic loading more realistic than the existing one. The new approach is believed to the incorporated in the Danish Deign Code for building structures.

Keywords: low seismicity, new design approach, earthquakes, Denmark

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Authors: Umesh Kumar Sinha, Y. K. Nayak, N. Kumar, Swapnil Saurav, Monika Kashyap

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The authors investigate the effect of system and operating parameters on the performance of high temperature solar concentrator for power generation. The effects of system and operating parameters were investigated using the developed mathematical expressions for collector efficiency, heat removal factor, fluid outlet temperature and power, etc. The results were simulated using C++program. The simulated results were plotted for investigation like effect of thermal loss parameter and radiative loss parameters on the collector efficiency, heat removal factor, fluid outlet temperature, rise of temperature and effect of mass flow rate of the fluid outlet temperature. In connection with the power generation, plots were drawn for the effect of (TM–TAMB) on the variation of concentration efficiency, concentrator irradiance on PM/PMN, evaporation temperature on thermal to electric power efficiency (Conversion efficiency) of the plant and overall efficiency of solar power plant.

Keywords: parabolic trough solar collector, radiative and thermal loss parameters, collector efficiency, heat removal factor, fluid outlet and inlet temperatures, rise of temperature, mass flow rate, conversion efficiency, concentrator irradiance

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Authors: Kiraz Esmeli, Alper Ozkan

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In this study, firstly, the effect of ultrasonic treatment on the stability of celestite suspension was investigated. In this context, the variations of the suspension stability with ultrasonic power, treatment time, immersion depth of ultrasonic probe, and treatment regime (batch and continuous) were determined. The experimental results showed that the suspension stability and zeta potential of celestite decreased with ultrasonic treatment. Also, the treatment time, immersion depth of probe, and treatment regime affected the stability of celestite suspension. Secondly, the effect of pre-treatment of the suspension with the ultrasonic process on the shear flocculation of celestite using sodium dodecyl sulfate (SDS) was studied and the variations of the flocculation, zeta potential, and contact angle of the mineral with SDS concentration were presented. It was found that the ultrasonic pre-treatment slightly improved the shear flocculation of celestite particles in accordance with the increase in the contact angles. In addition, the ultrasonic process again relatively reduced the magnitude of the negative potential of celestite particles in the presence of SDS.

Keywords: celestite, contact angle, suspension stability, ultrasonic treatment, zeta potential

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Authors: H. E. Ferrari, R. Farengo, C. F. Clauser

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Tungsten (W) will be used in ITER as one of the plasma facing components (PFCs). The W could migrate to the plasma center. This could have a potentially deleterious effect on plasma confinement. Electron cyclotron resonance heating (ECRH) can be used to prevent W accumulation. We simulated a series of H mode discharges in ASDEX U with PFC containing W, where central ECRH was used to prevent W accumulation in the plasma center. The experiments showed that the W density profiles were flat after a sawtooth crash, and become hollow in between sawtooth crashes when ECRH has been applied. It was also observed that a saturated kink mode was active in these conditions. We studied the effect of saturated kink like instabilities on the redistribution of W impurities. The kink was modeled as the sum of a simple analytical equilibrium (large aspect ratio, circular cross section) plus the perturbation produced by the kink. A numerical code that follows the exact trajectories of the impurity ions in the total fields and includes collisions was employed. The code is written in Cuda C and runs in Graphical Processing Units (GPUs), allowing simulations with a large number of particles with modest resources. Our simulations show that when the W ions have a thermal velocity distribution, the kink has no effect on the W density. When we consider the plasma rotation, the kink can affect the W density. When the average passing frequency of the W particles is similar to the frequency of the kink mode, the expulsion of W ions from the plasma core is maximum, and the W density shows a hollow structure. This could have implications for the mitigation of W accumulation.

Keywords: impurity transport, kink instability, tungsten accumulation, tungsten dynamics

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Authors: Nader Pourmahmoud, Amir Hassanzadeh

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This article investigates the effects of inlet pressure in a newly introduced vortex tube which has been equipped with an additional vortex chamber. A 3-D compressible turbulent flow computation has been carried out toward analysis of complex flow field in this apparatus. Numerical results of flows are derived by utilizing the standard k-ε turbulence model for analyzing high rotating complex flow field. The present research has focused on cooling effect and given a characteristics curve for minimum cool temperature. In addition, the effect of inlet pressure for both chambers has been studied in details. To be presented numerical results show that the effect of inlet pressure in second chamber has more important role in improving the performance of the vortex tube than first one. By increasing the pressure in the second chamber, cold outlet temperature reaches a higher decrease. When both chambers are fed with high pressure fluid, best operation condition of vortex tube occurs. However, it is not possible to feed both chambers with high pressure due to the conditions of working environment.

Keywords: energy separation, inlet pressure, numerical simulation, vortex chamber, vortex tube

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Authors: Marcel Hechler

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The purpose of this study is to understand the impact of entrepreneurs' receptiveness to opposing views on their entrepreneurial passion. Following a cross-cultural approach, we surveyed 1,228 entrepreneurs in seven developing and emerging countries. Besides a positive relationship between receptiveness to opposing views and harmonious passion for entrepreneurship, we found first evidence for a significant moderating effect of access to information reinforcing the positive main effect.

Keywords: harmonious passion, developing and emerging countries, self-determination theory, receptiveness to opposing views

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Authors: Iyagbaye O. Rich, Omoigberale O. Michael, Iyagbaye A. Louis

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The physical, chemical parameters and some trace contents of Ugbogui in Edo State, Nigeria were investigated from August 2015 to April 2016. Four stations were studied from upstream to downstream using standard methods. A total of thirty-three (33) physical and chemical characteristics and trace metal contents were examined; Air and water temperatures, depth, transparency, colour, turbidity, flow velocity, pH, total alkalinity, conductivity and dissolved solids etc. Other includes dissolved oxygen, oxygen saturation, biochemical oxygen demand, chloride, phosphate, sodium, nitrate, sulphate, potassium, calcium, magnesium, iron, lead, copper, zinc, nickel, cadmium, vanadium and chromium. Eleven (11) parameters exhibited clear seasonal variations. However, there were high significant differences (p < 0.01) in the values of depth, colour, total suspended solid, biochemical oxygen demand, chemical oxygen demand, chloride, bicarbonate, phosphate, sulphate, iron, manganese, zinc, copper, chromium and cadmium among the stations. The anthropogenic activities had negatively impacted at station 3 of the river, although most of the recorded values were still within permissible limits.

Keywords: anthropogenic activities, Nigeria, permissible limits, physical and chemical parameters, trace metal, water quality

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Authors: Ginpreet Kaur, Mohammad Yasir Usmani, Mohammed Kamil Khan

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Diabetes mellitus is a disease with a high global burden and results in significant morbidity and mortality. In India, the number of people suffering with diabetes is expected to rise from 19 to 57 million in 2025. At present, interest in herbal remedies is growing to reduce the side effects associated with conventional dosage form like oral hypoglycemic agents and insulin for the treatment of diabetes mellitus. Our aim was to investigate the antidiabetic activities of combinatorial extract of N. sativa & C. cassia in Streptozotocin induced type-I Diabetic Rats. Thus, the present study was undertaken to screen postprandial glucose excursion potential through α- glucosidase inhibitory activity (In Vitro) and effect of combinatorial extract of N. sativa & C. cassia in Streptozotocin induced type-I Diabetic Rats (In Vivo). In addition changes in body weight, plasma glucose, lipid profile and kidney profile were also determined. The IC50 values for both extract and Acarbose was calculated by extrapolation method. Combinatorial extract of N. sativa & C. cassia at different dosages (100 and 200 mg/kg orally) and Metformin (50 mg/kg orally) as the standard drug was administered for 28 days and then biochemical estimation, body weights and OGTT (Oral glucose tolerance test) were determined. Histopathological studies were also performed on kidney and pancreatic tissue. In In-Vitro the combinatorial extract shows much more inhibiting effect than the individual extracts. The results reveals that combinatorial extract of N. sativa & C. cassia has shown significant decrease in plasma glucose (p<0.0001), total cholesterol and LDL levels when compared with the STZ group The decreasing level of BUN and creatinine revealed the protection of N. sativa & C. cassia extracts against nephropathy associated with diabetes. Combination of N. sativa & C. cassia significantly improved glucose tolerance to exogenously administered glucose (2 g/kg) after 60, 90 and 120 min interval on OGTT in high dose streptozotocin induced diabetic rats compared with the untreated control group. Histopathological studies shown that treatment with N. sativa & C. cassia extract alone and in combination restored pancreatic tissue integrity and was able to regenerate the STZ damaged pancreatic β cells. Thus, the present study reveals that combination of N. sativa & C. cassia extract has significant α- glucosidase inhibitory activity and thus has great potential as a new source for diabetes treatment.

Keywords: lipid levels, OGTT, diabetes, herbs, glucosidase

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Authors: Joo-min Kim, Gi-wook Shin, Tae-ho Chung, Chul Park, Seong-hyun Kim, Namjung Kim

Abstract:

Mealworm (Tenebrio molitor) was evaluated to investigate the effect of partial or total replacement of fish meal in diets for olive flounder, Paralichthys olivaceus. Experimental groups of fish with average initial body weight (287.5 ± 7.24 g) were fed each with 4 isonitrogeneous (52% crude protein) diets formulated to include 0, 7, 17 and 27% (diets 1 to 4, respectively) of fish meal substituted with mealworm. After six weeks of feeding trials, fish fed with diet 3 revealed the highest values for live weight gain(42.10), specific growth rates (0.445 ± 0.089) as well as better feed conversion ratio (12.08) compared to the other group with statistically significant manner (p<0.05). Hepatosomatic index was showed no significant difference in diet 3 compared to the control group. An increase in weight gain and other growth associated parameters was observed in diet 3. These results clearly indicate that 17% of fish meal protein in bastard halibut diet can be replaced by mealworm not only without any adverse effect but also the effect of promoting growth performance.

Keywords: mealworm, olive flounder, Paralichthys olivaceus, Tenebrio molitor

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Authors: Yuan Li, Yitao Han, Zhao Zhu

Abstract:

In this paper, the effect of blasting loads on steel-concrete composite bridges has been investigated considering the slope reflection effect. Reasonable values of girder size, plate thickness, stiffening rib, and other design parameters were selected according to design specifications. Modified RHT (Riedel-Hiermaier-Thoma) was used as constitutive relation in analyses. In order to simulate the slope reflection effect, the slope of the bridge was precisely built in the model. Different blasting conditions, including top, middle, and bottom explosions, were simulated. The multi-Euler domain method based on fully coupled Lagrange and Euler models was adopted for the structural analysis of the explosion process using commercial software AUTODYN. The obtained results showed that explosion overpressure was increased by 3006, 879, and 449kPa, corresponding to explosions occurring at the top, middle, and bottom of the slope, respectively. At the same time, due to energy accumulation and transmission dissipation caused by slope reflection, the corresponding yield lengths of steel beams were increased by 8, 0, and 5m, respectively.

Keywords: steel-concrete composite bridge, explosion damage, slope reflection, blasting loads, RHT

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Authors: Aliya K. Salahova

Abstract:

Scientific thinking, characterized by purposeful knowledge-seeking and the harmonization of theory and facts, holds a crucial role in preparing young minds for an increasingly complex and technologically advanced world. This abstract presents a research study aimed at fostering scientific thinking in early childhood, focusing on children aged 5 to 9 years, through experiential learning in Kids Science Labs (STEM). The study utilized a longitudinal exploration design, spanning 240 weeks from September 2018 to April 2023, to evaluate the effectiveness of the Kids Science Labs program in developing scientific thinking skills. Participants in the research comprised 72 children drawn from local schools and community organizations. Through a formative psychology-pedagogical experiment, the experimental group engaged in weekly STEM activities carefully designed to stimulate scientific thinking, while the control group participated in daily art classes for comparison. To assess the scientific thinking abilities of the participants, a registration table with evaluation criteria was developed. This table included indicators such as depth of questioning, resource utilization in research, logical reasoning in hypotheses, procedural accuracy in experiments, and reflection on research processes. The data analysis revealed dynamic fluctuations in the number of children at different levels of scientific thinking proficiency. While the development was not uniform across all participants, a main leading factor emerged, indicating that the Kids Science Labs program and formative experiment exerted a positive impact on enhancing scientific thinking skills in children within this age range. The study's findings support the hypothesis that systematic implementation of STEM activities effectively promotes and nurtures scientific thinking in children aged 5-9 years. Enriching education with a specially planned STEM program, tailoring scientific activities to children's psychological development, and implementing well-planned diagnostic and corrective measures emerged as essential pedagogical conditions for enhancing scientific thinking abilities in this age group. The results highlight the significant and positive impact of the systematic-activity approach in developing scientific thinking, leading to notable progress and growth in children's scientific thinking abilities over time. These findings have promising implications for educators and researchers, emphasizing the importance of incorporating STEM activities into educational curricula to foster scientific thinking from an early age. This study contributes valuable insights to the field of science education and underscores the potential of STEM-based interventions in shaping the future scientific minds of young children.

Keywords: Scientific thinking, education, STEM, intervention, Psychology, Pedagogy, collaborative learning, longitudinal study

Procedia PDF Downloads 61