Search results for: Influence maximization

Authors: O. Ansari, H. Hafs, A. Bah, M. Asbik, M. Malha, M. Bakhouya

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Water is one of the most important and vulnerable natural resources due to human activities and climate change. Water-level continues declining year after year and it is primarily caused by sustained, extensive, and traditional usage methods. Improving water utilization becomes an urgent issue in order satisfy the increasing population needs. Desalination of seawater or brackish water could help in increasing water potential. However, a cost-effective desalination process is required. The most appropriate method for performing this desalination is solar-driven distillation, given its simplicity, low cost and especially the availability of the solar energy source. The main objective of this paper is to demonstrate the influence of coupling integrated basin plate by fins with preheating by solar collector on the performance of solar still. The energy balance equations for the various elements of the solar still are introduced. A numerical example is used to show the efficiency of the proposed solution.

Keywords: Active solar still, Brackisch water, desalination, fins, solar collector.

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Authors: Ethan Shafer, Timothy Graziano, Jay Fisher

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This research seeks to answer whether first-year courses at institutions of higher learning can impact STEM major selection. Unlike many universities, an entry-level technology course (often referred to as CS0) is required for all United States Military Academy (USMA) students–regardless of major–in their first year of attendance. Students at the Academy choose their major at the end of their first year of studies. Through student responses to a multi-semester survey, this paper identifies a number of factors that potentially influence STEM major selection. Student demographic data, pre-existing exposure and access to technology, perceptions of STEM subjects, and initial desire for a STEM major are captured before and after taking a CS0 course. An analysis of factors that contribute to student perception of STEM and major selection are presented. This work provides recommendations and suggestions for institutions currently providing or looking to provide CS0-like courses to their students.

Keywords: STEM major, STEM, pedagogy, digital literacy.

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Authors: Kaliyaperumal Anandavel, Raghu V. Prakash, Antonio Davis

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This paper presents the influence of preloading on a) the contact tractions, b) slip levels and c) stresses at the dovetail blade-disc interface of an aero-engine through a three-dimensional (3D) finite element (FE) modeling and analysis. The preloading is applied by an interference fit at the dovetail interface and the bulk loading is applied through the rotational speed of rotor. Preloading at the dovetail interface reduces the peak contact pressure developed due to bulk loading up to 35%, and reduces the peak contact pressure and stress difference between top and bottom contact edges. Increasing the level of preloading reduces the cyclic stress amplitude at the interface up to certain values of preload and as a consequence, an improvement in fatigue life could be expected. Fretting damage, due to vibration and wind milling effect during engine ground condition, can be minimized by preloading the dovetail interface.

Keywords: Dovetail interface, Preload, Interference fit, ContactStress, Fretting Fatigue.

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Authors: Yanhua Jin, Won Suk Lee

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The two-dimensional gel electrophoresis method (2-DE) is widely used in Proteomics to separate thousands of proteins in a sample. By comparing the protein expression levels of proteins in a normal sample with those in a diseased one, it is possible to identify a meaningful set of marker proteins for the targeted disease. The major shortcomings of this approach involve inherent noises and irregular geometric distortions of spots observed in 2-DE images. Various experimental conditions can be the major causes of these problems. In the protein analysis of samples, these problems eventually lead to incorrect conclusions. In order to minimize the influence of these problems, this paper proposes a partition based pair extension method that performs spot-matching on a set of gel images multiple times and segregates more reliable mapping results which can improve the accuracy of gel image analysis. The improved accuracy of the proposed method is analyzed through various experiments on real 2-DE images of human liver tissues.

Keywords: Proteomics, spot-matching, two-dimensionalelectrophoresis.

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Authors: Siska Soesanti, Norihiro Nakai

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Bandung city center can be deemed as economic, social and cultural center. However the city center suffers from deterioration. The retail activities tend to shift outward the city center. Numerous idyllic residences changed into business premises in two villages situated in the north part of the city during 1990s, especially after a new highway and flyover opened. According to space syntax theory, the pattern of spatial integration in the urban grid is a prime determinant of movement patterns in the system. The syntactic analysis results show the flyover has insignificant influence on street network in the city center. However the flyover has been generating a major difference in the new commercial area since it has become relatively as strategic as the city center. Besides street network, local government policy, rapid private motorization and particular condition of each site also played important roles in encouraging the current commercial areas to flourish.

Keywords: City center, commercial area, space syntax, street network.

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Authors: A. Rohana, A. M., Fadzilah Adibah, M. S. Muhammad Roji

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Oleic acid (C18:1) play an important role in proliferation of fat cells. In this study, the effect of oleate on cells viability in 3T3-L1 cells (fat cells) was investigated. The 3T3-L1 cells were treated with various concentrations of oleate in the presence of 23 mM glucose. Oleate was added to adipogenic media (day 0) to investigate the influence of oleate on proliferation of postconfluent preadipocytes after 24 h induction. 0.1 mM oleate promoted cell division by increasing 33.9% number of cells from basal control in postconfluent preadipocytes. However, there were no significantly different in cells viability with control cells when oleate concentrations were increased up to 0.5 mM. When added to differentiated adipocytes (day 12) for 48 h, the number of cells decreased as oleate concentrations increased. 92.7% of cells lost demonstrated apoptosis and necrosis after 48 h with 0.5 mM oleate. The fluorochrome staining was examined under fluorescence microscopy using acridine orange and ethidium bromide double staining. Furthermore, the presence of high lactate (60.6% increased from basal control) released into plasma has shown the direct cytotoxicity of 0.5 mM oleate on adipocytes.

Keywords: adipocytes, apoptosis, oleate, postconfluentpreadipocytes

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Authors: G. T. Ramos-Escobedo, E. T. Pecina-Treviño, L. F. Camacho-Ortegon, E. Orrantia-Borunda

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The mineral bioflotation represents a viable alternative for the evaluation of new processes benefit alternative. The adsorption bacteria on minerals surfaces will depend mainly on the type of the microorganism as well as of the studied mineral surface. In the current study, adhesion of S. carnosus on coal was studied. Several methods were used as: DRX, Fourier Transform Infra-Red (FTIR) adhesion isotherms and kinetic. The main goal is to recovery of organic matter by the microflotation process on coal particles with biological reagent (S. carnosus). Adhesion tests revealed that adhesion took place after of 8 h at pH 9. The results suggest that the adhesion of bacteria to solid substrates can be considered an abiotic physicochemical process that is consequently governed by bacterial surface properties such as their specific surface area, hydrophobicity and surface functionalities. The greatest coal fine flotability was of 75%, after 5 min of flotation.

Keywords: Fine Coal, Bacteria, Adhesion, recovery matter organic.

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Authors: A. Khafaji, R. Saadane, J. El Abbadi, M. Belkasmi

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The main objectif of this paper is to present a tool that we have developed subject to characterize and modelling indoor radio channel propagation at millimetric wave. The tool is based on the ray tracing technique (RTT). As, in realistic environment we cannot neglect the significant impact of Human Body Shadowing and other objects in motion on indoor 60 GHz propagation channel. Hence, our proposed model allows a simulation of propagation in a dynamic indoor environment. First, we describe a model of human body. Second, RTT with this model is used to simulate the propagation of millimeter waves in the presence of persons in motion. Results of the simulation show that this tool gives results in agreement with those reported in the literature. Specially, the effects of people motion on temporal channel properties.

Keywords: Simulation. 60 GHz band, Ray Tracing Technique, Indoor channel, Propagation, Human Body Model, Level crossing rate,

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Authors: Luísa P. Cruz-Lopes, Liliana Rodrigues, Idalina Domingos, José Ferreira, Luís Teixeira de Lemos, Bruno Esteves

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Currently, the polyurethanes industry is dependent on fossil resources to obtain their basic raw materials (polyols and isocyanate), as these are obtained from petroleum products. The aim of this work was to use biopolyols from liquefied Pseudotsuga (Pseudotsuga menziesii) and Turkey oak (Quercus cerris) barks for the production of polyurethane foams and optimize the process. Liquefaction was done with glycerol catalyzed by KOH. Foams were produced following different formulations and using biopolyols from both barks. Subsequently, the foams were characterized according to their mechanical properties and the reaction of the foam formation was monitored by FTIR-ATR. The results show that it is possible to produce polyurethane foams using bio-based polyols and the liquefaction conditions are very important because they influence the characteristics of biopolyols and, consequently the characteristics of the foams. However, the process has to be further optimized so that it can obtain better quality foams.

Keywords: Bio-based polyol, mechanical tests, polyurethane foam, Pseudotsuga bark, renewable resources, Turkey oak bark.

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Authors: Mohammad Reza Pirestani, Mehdi Shafaghati, Amir Ahmad Dehghani

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From the beginning of creation, human being has ever fought against the ecosystem by changes has made in environment. The most environmental changes on the nature have been done after starting the concentrated life in the same region. Dams are one of the most important buildings in water resources and transferring. These buildings have been made from old times without access to hydrological, hydraulically, hydro mechanical information. Dams have positive and negative effects on environment. Constructing a dam relatively causes equal ecological consequences. According to different criteria, environmental effects of dams can lead short term and long term damages. These effects may influence on the situation and treatment of meteorology, biology, culture, ancient works, etc and severely causes to change and complicate it. So considering importance of positive effects of dam construction, it is necessary to minimize negative environmental effects of dams to achieve a stable development. In this article the considered effects and their solutions in influencing on assessment of destructive environmental effects of dams construction have been surveyed and presented.

Keywords: Dam, Environment, Water Resources, Assessment

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Authors: Abdulrahman A. Alghamdi, Paul M. Mummery, Mohammad A. Sheikh

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In this paper, 3D image based composite unit cell is constructed from high resolution tomographic images. Through-thickness thermal diffusivity and in-plane Young’s modulus are predicted for the composite unit cell. The accuracy of the image based composite unit cell is tested by comparing its results with the experimental results obtained from laser flash and tensile test. The FE predictions are in close agreement with experimental results. Through-thickness thermal diffusivity and in-plane Young’s modulus of a virgin C/C composite are predicted by replacing the properties of air (porosity) with the properties of carbon matrix. The effect of porosity was found to be more profound on thermal diffusivity than young’s modulus.

Keywords: Porosity, C/C composite, image based FE modelling, CMC.

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Authors: Aline F. Marcon, Eduardo F. da Silva, Marina Bouzon

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The impact of lean management on environmental sustainability is the research line that receives the most attention from academicians. Therefore, the social dimension of sustainable development has so far received less attention. This paper aims to evaluate the impact of intra-plant lean manufacturing practices on social sustainability indicators extracted from the Global Reporting Initiative (GRI) parameters. The method is two-phased, including MCDM approach to uncover the most relevant practices regarding social performance and Interpretive Structural Modeling (ISM) method to reveal the structural relationship among lean practices. Professionals from the academic and industrial fields answered the questionnaires. From the results of this paper, it is possible to verify that practices such as “Safety Improvement Programs”, “Total Quality Management” and “Cross-functional Workforce” are the ones which have the most positive influence on the set of GRI social indicators.

Keywords: Indicators, ISM, lean, social, sustainability.

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Authors: D. Mirauda, M. Greco, A. Volpe Plantamura

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The necessity of updating the numerical models inputs, because of geometrical and resistive variations in rivers subject to solid transport phenomena, requires detailed control and monitoring activities. The human employment and financial resources of these activities moves the research towards the development of expeditive methodologies, able to evaluate the outflows through the measurement of more easily acquirable sizes. Recent studies highlighted the dependence of the entropic parameter on the kinematical and geometrical flow conditions. They showed a meaningful variability according to the section shape, dimension and slope. Such dependences, even if not yet well defined, could reduce the difficulties during the field activities, and also the data elaboration time. On the basis of such evidences, the relationships between the entropic parameter and the geometrical and resistive sizes, obtained through a large and detailed laboratory experience on steady free surface flows in conditions of macro and intermediate homogeneous roughness, are analyzed and discussed.

Keywords: Froude number, entropic parameter, roughness, water discharge.

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Authors: Thiago R. Pereira

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The philosophical hermeneutics is able to change the Brazilian Judiciary because of the understanding of the characteristics of the human being. It is impossible for humans, to be invested in the function of being a judge, making absolutely neutral decisions, but the philosophical hermeneutics can assist the judge making impartial decisions, based on the federal constitution. The normative legal positivism imagined a neutral judge, a judge able to try without any preconceived ideas, without allowing his/her background to influence him/her. When a judge arbitrates based on legal rules, the problem is smaller, but when there are no clear legal rules, and the judge must try based on principles, the risk of the decision is based on what they believe in. Solipsistically, this issue gains a huge dimension. Today, the Brazilian judiciary is independent, but there must be a greater knowledge of philosophy and the philosophy of law, partially because the bigger problem is the unpredictability of decisions made by the judiciary. Actually, when a lawsuit is filed, the result of this judgment is absolutely unpredictable. It is almost a gamble. There must be the slightest legal certainty and predictability of judicial decisions, so that people, with similar cases, may not receive opposite sentences. The relativism, since classical antiquity, believes in the possibility of multiple answers. Since the Greeks in in the sixth century before Christ, through the Germans in the eighteenth century, and even today, it has been established the constitution as the great law, the Groundnorm, and thus, the relativism of life can be greatly reduced when a hermeneut uses the Constitution as North interpretational, where all interpretation must act as the hermeneutic constitutional filter. For a current philosophy of law, that inside a legal system with a Federal Constitution, there is a single correct answer to a specific case. The challenge is how to find this right answer. The only answer to this question will be that we should use the constitutional principles. But in many cases, a collision between principles will take place, and to resolve this issue, the judge or the hermeneut will choose a solipsism way, using what they personally believe to be the right one. For obvious reasons, that conduct is not safe. Thus, a theory of decision is necessary to seek justice, and the hermeneutic philosophy and the linguistic turn will be necessary for one to find the right answer. In order to help this difficult mission, it will be necessary to use philosophical hermeneutics in order to find the right answer, which is the constitutionally most appropriate response. The constitutionally appropriate response will not always be the answer that individuals agree to, but we must put aside our preferences and defend the answer that the Constitution gives us. Therefore, the hermeneutics applied to Law, in search constitutionally appropriate response, should be the safest way to avoid judicial individual decisions. The aim of this paper is to present the science of law starting from the linguistic turn, the philosophical hermeneutics, moving away from legal positivism. The methodology used in this paper is qualitative, academic and theoretical, philosophical hermeneutics with the mission to conduct research proposing a new way of thinking about the science of law. The research sought to demonstrate the difficulty of the Brazilian courts to depart from the secular influence of legal positivism. Moreover, the research sought to demonstrate the need to think science of law within a contemporary perspective, where the linguistic turn, philosophical hermeneutics, will be the surest way to conduct the science of law in the present century.

Keywords: Hermeneutic, right answer, solipsism, Brazilian Judiciary.

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Authors: Maizatul A. Musa

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Not many studies have been undertaken on shareholder activism in emerging economies, including Malaysia. Shareholder activism in emerging economies is on the rise. This paper seeks to comprehend the elements of this activism that are unique to Malaysia, specifically with respect to how the agency problem is controlled through shareholder activism in improving corporate governance practices within target companies. Through shareholder activism, shareholders make contact with a target company to voice their dissatisfaction, suggestions, or recommendations. This paper utilises agency theory to explain institutional shareholder activism. This theory has been extensively used within literature on corporate governance with regards to shareholder activism. The effectiveness of shareholder activism in improving corporate governance will be examined as well. This research provides a further understanding of shareholder activism in emerging economies, such as Malaysia; this research also has the potential to enhance shareholder activism and corporate governance practices in general.

Keywords: Agency Theory, Corporate Governance, Emerging Economies, Institutional Shareholder Activism, Malaysia.

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Authors: B. Gangloff, L. Mayoral, A. Rezrazi

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Three types of salary distribution are usually proposed by the theorists of distributive justice: Equality, equity and need. Their influence has been studied, taking into consideration (in terms of equity) the performance of the employees and their degree of allegiance/rebellion in what regards discriminatory hierarchical orders, by taking into account the reasons of such allegiance/rebellion (allegiance out of conviction, legalism or opportunism/ethical rebellion). Conducted in Argentina, the study has confronted 480 students (240 male and 240 female) with a practical case in which they had to advise a manager of a real estate agency on the allocation of a bonus amongst his employees. The latter were characterized according to their respective performance, one of them being further defined as being (or not) in a financial need and as having complied (or not) with a discriminatory hierarchical order regarding foreigners. The results show that the distribution of the bonus only follows the rules of equity and need: The employees more efficient, allegiant or in need, are rewarded more than the others. It is also noteworthy that the allegiant employees are rewarded in the same way, regardless of the reason for their allegiance, and that the employee who refuses to adopt a discriminatory conduct is penalized.

Keywords: Distributive justice, equity, performance, allegiance, ethic.

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Authors: Roslina Ibrahim, Azizah Jaafar

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Educational games (EG) seem to have lots of potential due to digital games popularity and preferences of our younger generations of learners. However, most studies focus on game design and its effectiveness while little has been known about the factors that can affect users to accept or to reject EG for their learning. User acceptance research try to understand the determinants of information systems (IS) adoption among users by investigating both systems factors and users factors. Upon the lack of knowledge on acceptance factors for educational games, we seek to understand the issue. This study proposed a model of acceptance factors based on Unified Theory of Acceptance and Use of Technology (UTAUT). We use original model (performance expectancy, effort expectancy and social influence) together with two new determinants (learning opportunities and enjoyment). We will also investigate the effect of gender and gaming experience that moderate the proposed factors.

Keywords: educational games, games acceptance, user acceptance model, UTAUT

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Authors: Pawel Glibowski, Agnieszka Glibowska

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The rheological properties, structure and potential synergistic interactions of whey proteins (1-6%) and inulin (20%) in mixed gels in the presence of CaCl2 was the aim of this study. Whey proteins have a strong influence on inulin gel formation. At low concentrations (2%) whey proteins did not impair in inulin gel formation. At higher concentration (4%) whey proteins impaired inulin gelation and inulin impaired the formation of a Ca2+-induced whey protein network. The presence of whey proteins at a level allowing for protein gel network formation (6%) significantly increased the rheological parameters values of the gels. SEM micrographs showed that whey protein structure was coated by inulin moieties which could make the mixed gels firmer. The protein surface hydrophobicity measurements did not exclude synergistic interactions between inulin and whey proteins, however. The use of an electrophoretic technique did not show any stable inulin-whey protein complexes.

Keywords: gels, hydrophobicity, inulin, SEM, whey proteins.

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Authors: S. Niksarlioglu, F. Kulahci

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Earthquakes are natural phenomena that occur with influence of a lot of parameters such as seismic activity, changing in the ground waters' motion, changing in the water-s temperature, etc. On the other hand, the radon gas concentrations in soil vary as nonlinear generally with earthquakes. Continuous measurement of the soil radon gas is very important for determination of characteristic of the seismic activity. The radon gas changes as continuous with strain occurring within the Earth-s surface during an earthquake and effects from the physical and the chemical processes such as soil structure, soil permeability, soil temperature, the barometric pressure, etc. Therefore, at the modeling researches are notsufficient to knowthe concentration ofradon gas. In this research, we determined relationships between radon emissions based on the environmental parameters and earthquakes occurring along the East Anatolian Fault Zone (EAFZ), Turkiye and predicted magnitudes of some earthquakes with the artificial neural network (ANN) model.

Keywords: Earthquake, Modeling, Prediction, Radon.

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Authors: Nichanant Sermsri, Chonmapat Torasa

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The objective of this research was to investigate the efficiency of the light emitting diode (LED) tube in various color lights used to lure the adult coconut hispine beetle. The research was conducted by setting the forward bias on LED tubes, and the next step was to test luminous efficacy and quantity of electricity used to power each LED tube in different color lights. Finally, the researcher examined the efficiency of each color-light LED tube to lure the adult coconut hispine beetle.

The results showed that the ultraviolet LED tubes had the most capacity to allure the adult coconut hispine beetles with the percentage of 82.92, followed by the blue LED tubes with the percentage of 59.76. Whereas the yellow, pink, red and warm white LED tubes had no influence to the adult coconut hispine beetles.

Keywords: Coconut Hispine Beetle, Color Lights, Lighting Efficiency, LED Tubes.

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Authors: M. Schulze, P. Crespo Del Granado

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This paper considers the influence of promotion instruments for renewable energy sources (RES) on a multi-energy modeling framework. In Europe, so called Feed-in Tariffs are successfully used as incentive structures to increase the amount of energy produced by RES. Because of the stochastic nature of large scale integration of distributed generation, many problems have occurred regarding the quality and stability of supply. Hence, a macroscopic model was developed in order to optimize the power supply of the local energy infrastructure, which includes electricity, natural gas, fuel oil and district heating as energy carriers. Unique features of the model are the integration of RES and the adoption of Feed-in Tariffs into one optimization stage. Sensitivity studies are carried out to examine the system behavior under changing profits for the feed-in of RES. With a setup of three energy exchanging regions and a multi-period optimization, the impact of costs and profits are determined.

Keywords: Distributed generation, optimization methods, power system modeling, renewable energy.

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Authors: Kelly R. Mazzer, Debra J. Rickwood, Thea Vanags

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Young people have a high prevalence of mental health problems, yet tend not to seek help. Trusted adults in young people-s lives, such as teachers and sports coaches, can make a major positive contribution to the mental health of young people. Teachers and sports coaches may be in a position to be effective in supporting young people-s mental health through promotion, prevention and early intervention. This study reports findings from interviews with 21 teachers and 13 sports coaches of young people aged 12 to 18 in Canberra, Australia, regarding their perceptions of the relevance and effectiveness of their role in supporting young people-s mental health. Both teachers and coaches perceived having influential but slightly different roles to play in supporting mental health. There may be potential to elevate the influence of teachers and coaches as sources of support for young people and their mental health care.

Keywords: Early intervention, mental health promotion, coaches, teachers, young people

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Authors: R. Doubrava, R. Růžek

Abstract:

Nonstandard tests are necessary for analyses and verification of new developed structural and technological solutions with application of composite materials. One of the most critical primary structural parts of a typical aerospace structure is T-joint. This structural element is loaded mainly in shear, bending, peel and tension. The paper is focused on the shear loading simulations. The aim of the work is to obtain a representative uniform distribution of shear loads along T-joint during the mechanical testing. A new design of T-joint test procedure, numerical simulation and optimization of representative boundary conditions are presented. The different conditions and inaccuracies both in simulations and experiments are discussed. The influence of different parameters on stress and strain distributions is demonstrated on T-joint made of CFRP (carbon fibre reinforced plastic). A special test rig designed by VZLU (Aerospace Research and Test Establishment) for T-shear test procedure is presented.

Keywords: T-joint, shear, composite, mechanical testing, Finite Element analysis, methodology.

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Authors: Samorn Hirunpraditkoon, Nathaporn Tunthong, Anotai Ruangchai, Kamchai Nuithitikul

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The production of activated carbon from low or zero cost of agricultural by-products or wastes has received great attention from academics and practitioners due to its economic and environmental benefits. In the production of bamboo furniture, a significant amount of bamboo waste is inevitably generated. Therefore, this research aimed to prepare activated carbons from bamboo furniture waste by chemical (KOH) activation and determine their properties and adsorption capacities for water treatment. The influence of carbonization time on the properties and adsorption capacities of activated carbons was also investigated. The finding showed that the bamboo-derived activated carbons had microporous characteristics. They exhibited high tendency for the reduction of impurities present in effluent water. Their adsorption capacities were comparable to the adsorption capacity of a commercial activated carbon regarding to the reduction in COD, TDS and turbidity of the effluent water.

Keywords: Activated carbon, Bamboo, Water treatment, Chemical activation.

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Authors: C. P. Parente, M. J. Reis Lima, E. Teixeira-Lemos, M. M. Moreira, Aquiles A. Barros, Luís F. Guido

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Broccoli has been widely recognized as a wealthy vegetable which contains multiple nutrients with potent anti-cancer properties. Lamb’s lettuce has been used as food for many centuries but only recently became commercially available and literature is therefore exiguous concerning these vegetables. The aim of this work was to evaluate the influence of the extraction conditions on the yield of phenolic compounds and the corresponding antioxidant capacity of broccoli and lamb’s lettuce. The results indicate that lamb’s lettuce, compared to broccoli, contains simultaneously a large amount of total polyphenols as well as high antioxidant activity. It is clearly demonstrated that extraction solvent significantly influences the antioxidant activity. Methanol is the solvent that can globally maximize the antioxidant extraction yield. The results presented herein prove lamb’s lettuce as a very interesting source of polyphenols, and thus a potential health-promoting food.

Keywords: Broccoli, lamb’s lettuce, extraction, antioxidant activity, phenolic compounds.

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Authors: Ilze Stokmane

Abstract:

Economic processes underway in the country directly and indirectly affect the welfare of the people and the social environment, starting with job security and having a direct impact on the qualitative and safe living environment.

The paper describes existing situation and gives analysis of the regional development policy determination and implementation in the all three Baltic countries. According statistical indicators there are differences between implementation of the regional development activities between all Baltic countries and in regions of inside each country.

It is analyzed more detail differences between regions in Latvia, Lithuania and Estonia according possibility to evaluate success of development processes in regions of the Baltic countries. The descriptive analyze of documents, statistical indicators at national level and regional level were used in the research.

Keywords: Baltic countries, city environment, regional development, urban areas.

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Authors: M. Haj Seyed Hadi, M. Taghi Darzi, Z. Ghandeharialavijeh, GH. Riazi

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The main objective of this study was to determine the effects of vermicompost and amino acids on the qualitative and quantitative yield of chamomile. The experiment was conducted during the growing season of 2010 at the Alborz Medical Research Center. The Treatment groups consisted of vermicompost (0, 5, 10, 15 and 20 tons/ha) and the sprays of amino acids (budding stag, flowering stage, and budding + flowering stage). The experimental design was a factorial experiment based on Randomized Complete Block Design (RCBD) with three replications. The present results have shown that the highest plant height, flower head diameter, fresh and dry flower yield and significant essential oil content were obtained by using 20- ton vermicompost per hectare. Effects of amino acids were similar to those seen in vermicompost treatment and all measured traits were seen to be significant after the spray of amino acids at the budding + flowering stage).

Keywords: Vermicompost, amino acids, chamomile, yield

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Authors: Hossein Shokouhmand , Koohyar Vahidkhah, Mohammad A. Esmaeili

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A numerical investigation of surface heat transfer characteristics of turbulent air flows in different parallel plate grooved channels is performed using CFD code. The results are obtained for Reynolds number ranging from 10,000 to 30,000 and for arc-shaped and rectangular grooved channels. The influence of different geometric parameters of dimples as well as the number of them and the geometric and thermophysical properties of channel walls are studied. It is found that there exists an optimum value for depth of dimples in which the largest wall heat flux can be achieved. Also, the results show a critical value for the ratio of wall thermal conductivity to the one of fluid in which the dependence of wall heat flux to this ratio almost vanishes. In most cases examined, heat transfer enhancement is larger for arc-shaped grooved channels than rectangular ones.

Keywords: dimple, heat transfer enhancement, Numerical, optimum value, turbulent air flow.

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Authors: A.R.M. Kasim, N.F. Mohammad, Aurangzaib, S. Sharidan

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The present paper considers the steady free convection boundary layer flow of a viscoelastic fluid on solid sphere with Newtonian heating. The boundary layer equations are an order higher than those for the Newtonian (viscous) fluid and the adherence boundary conditions are insufficient to determine the solution of these equations completely. Thus, the augmentation an extra boundary condition is needed to perform the numerical computational. The governing boundary layer equations are first transformed into non-dimensional form by using special dimensionless group and then solved by using an implicit finite difference scheme. The results are displayed graphically to illustrate the influence of viscoelastic K and Prandtl Number Pr parameters on skin friction, heat transfer, velocity profiles and temperature profiles. Present results are compared with the published papers and are found to concur very well.

Keywords: boundary layer flow, Newtonian heating, sphere, viscoelastic fluid.

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Authors: C. A. Alves, A. I. Calvo, A. Castro, R. Fraile, M. Evtyugina, E. F. Bate-Epey

Abstract:

In July 2012, an indoor/outdoor monitoring programme was undertaken in two university sports facilities: a fronton and a gymnasium. Comfort parameters (temperature, relative humidity, CO and CO2) and total volatile organic compounds (VOCs) were continuously monitored. Concentrations of NO2, carbonyl compounds and individual VOCs were obtained. Low volume samplers were used to collect particulate matter (PM10). The minimum ventilation rates stipulated for acceptable indoor air quality were observed in both sports facilities. It was found that cleaning activities may have a large influence on the VOC levels. Acrolein was one of the most abundant carbonyl compounds, showing concentrations above the recommended limit. Formaldehyde was detected at levels lower than those commonly reported for other indoor environments. The PM10 concentrations obtained during the occupancy periods ranged between 38 and 43μgm-3 in the fronton and from 154 to 198μgm-3 in the gymnasium.

Keywords: Air exchange rates, carbonyls, gymnasiums, indoor air quality, PM10, VOCs.

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