Search results for: saturation effects

Authors: Al-Shabatat, M. Ahmad, Abbas, M., Ismail, H. Nizam

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Achievement motivation is believed to promote giftedness attracting people to invest in many programs to adopt gifted students providing them with challenging activities. Intellectual giftedness is founded on the fluid intelligence and extends to more specific abilities through the growth and inputs from the achievement motivation. Acknowledging the roles played by the motivation in the development of giftedness leads to an effective nurturing of gifted individuals. However, no study has investigated the direct and indirect effects of the achievement motivation and fluid intelligence on intellectual giftedness. Thus, this study investigated the contribution of motivation factors to giftedness development by conducting tests of fluid intelligence using Cattell Culture Fair Test (CCFT) and analytical abilities using culture reduced test items covering problem solving, pattern recognition, audio-logic, audio-matrices, and artificial language, and self report questionnaire for the motivational factors. A number of 180 highscoring students were selected using CCFT from a leading university in Malaysia. Structural equation modeling was employed using Amos V.16 to determine the direct and indirect effects of achievement motivation factors (self confidence, success, perseverance, competition, autonomy, responsibility, ambition, and locus of control) on the intellectual giftedness. The findings showed that the hypothesized model fitted the data, supporting the model postulates and showed significant and strong direct and indirect effects of the motivation and fluid intelligence on the intellectual giftedness.

Keywords: Achievement motivation, Intellectual Giftedness, Fluid Intelligence, Analytical Giftedness, CCFT, Structural EquationModeling.

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Authors: Ahmet Ay, Hakan Acet, Ceyhun Can Özcan

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Economic freedoms, most emphasized issue in the recent years, are considered to affect economic growth and performance via institutional structure. In this context, a model that includes Turkey and Middle East Countries, and where the effects of economic freedom on growth are examined, was formed. For the groups of countries determined, in the study carried out by using the dataset belonging the period of 2004 - 2009, between economic freedoms and growth, a negative relationship was observed as group. In the sense of individual effects, it was identified that there was a positive relationship in terms of some Middle East Countries and Turkey.

Keywords: Economic Freedoms, Economic Growth, Freedoms.

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Authors: George D. Ranis, Valasia Iakovoglou, George N. Zaimes

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Fires is one of the main types of disturbances that shape ecosystems in the Mediterranean region. However nowadays, climate alterations towards higher temperatures result on increased levels of fire intensity, frequency and spread as well as difficulties for natural regeneration to occur. Thasos Island is one of the Greek islands that has experienced those problems. Since 1984, a series of wildfires led to the reduction of forest cover from 61.6% to almost 20%. The negative impacts were devastating in many different aspects for the island. The absence of plant cover, post-wildfire precipitation and steep slopes were the major factors that induced severe soil erosion and intense floods. That also resulted to serious economic problems to the local communities and the inability of the burnt areas to regenerate naturally. Despite the substantial amount of published work regarding Thasos wildfires, there is no information related to post-wildfire effects on factors such as soil erosion. More research related to post-fire effects should help to an overall assessment of the negative impacts of wildfires on land degradation through processes such as soil erosion and flooding.

Keywords: Erosion, land degradation, Mediterranean islands, regeneration, Thasos, wildfires.

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Authors: Diako Azizi, Hosein Heydari, Ahmad Gholami

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Today with the rapid growth of telecommunications equipment, electronic and developing more and more networks of power, influence of electromagnetic waves on one another has become hot topic discussions. So in this article, this issue and appropriate mechanisms for EMC operations have been presented. First, a source of alternating current (50 Hz) and a clear victim in a certain distance from the source is placed. With this simple model, the effects of electromagnetic radiation from the source to the victim will be investigated and several methods to reduce these effects have been presented. Therefore passive and active shields have been used. In some steps, shielding effectiveness of proposed shields will be compared. . It should be noted that simulations have been done by the finite element method (FEM).

Keywords: Electrical field, field distribution, finite element method, shielding effectiveness

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Authors: Kanita Thanacharoenchanaphas, Orose Rugchati

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This study assessed the effects of climate change on Thai soybeans under simulation situations. Our study is focused on temperature variability and effects on growth, yield, and genetic changes in 2 generations of Chiang Mai 60 cultivars. In the experiment, soybeans were exposed to 3 levels of air temperature for 8 h day-1 in an open top chamber for 2 cropping periods. Air temperature levels in each treatment were controlled at 30-33°C (± 2.3) for LT-treatment, 33-36°C ( ± 2.4) for AT-treatment, and 36-40 °C ( ± 3.2) for HT-treatment, respectively. Positive effects of high temperature became obvious at the maturing stage when yield significantly increased in both cropping periods. Results in growth indicated that shoot length at the pre-maturing stage (V3-R3) was more positively affected by high temperature than at the maturing stage. However, the positive effect on growth under high temperature was not found in the 2nd cropping period. Finally, genetic changes were examined in phenotype characteristics by the AFLPs technique. The results showed that the high temperature factor clearly caused genetic change in the soybeans and showed more alteration in the 2nd cropping period.

Keywords: simulation, air temperature, variability, Thai soybean, yield , genetic change

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Authors: Burak Yildirim, Muhsin Tunay Gençoğlu

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A microgrid (MG) is a small power grid composed of localized medium or low level power generation, storage systems, and loads. In this paper, the effects of a MG on power systems voltage stability are shown. The MG model, designed to demonstrate the effects of the MG, was applied to the IEEE 14 bus power system which is widely used in power system stability studies. Eigenvalue and modal analysis methods were used in simulation studies. In the study results, it is seen that MGs affect system voltage stability positively by increasing system voltage instability limit value for buses of a power system in which MG are placed.

Keywords: Eigenvalue analysis, microgrid, modal analysis, voltage stability.

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Authors: Maninder Kaur Gill, Alpana Agarwal

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It is practically not feasible to measure the open-loop voltage gain of the operational amplifier in the open loop configuration. It is because the open-loop voltage gain of the operational amplifier is very large. In order to avoid the saturation of the output voltage, a very small input should be given to operational amplifier which is not possible to be measured practically by a digital multimeter. A test circuit for measurement of open loop voltage gain of an operational amplifier has been proposed and verified using simulation tools as well as by experimental methods on breadboard. The main advantage of this test circuit is that it is simple, fast, accurate, cost effective, and easy to handle even on a breadboard. The test circuit requires only the device under test (DUT) along with resistors. This circuit has been tested for measurement of open loop voltage gain for different operational amplifiers. The underlying goal is to design testable circuits for various analog devices that are simple to realize in VLSI systems, giving accurate results and without changing the characteristics of the original system. The DUTs used are LM741CN and UA741CP. For LM741CN, the simulated gain and experimentally measured gain (average) are calculated as 89.71 dB and 87.71 dB, respectively. For UA741CP, the simulated gain and experimentally measured gain (average) are calculated as 101.15 dB and 105.15 dB, respectively. These values are found to be close to the datasheet values.

Keywords: Device under test, open-loop voltage gain, operational amplifier, test circuit.

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Authors: Victoria C. Valdebenito

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Located within the context of accelerating globalization in the 21^st-century knowledge society, this paper focuses on one selected university in Chile at which radical curriculum policy changes have been taking place, diverging from the traditional curriculum in Chile at the undergraduate level as a section of a larger investigation. Using a ‘policy trajectory’ framework, and guided by the interpretivist approach to research, interview transcripts and institutional documents were analyzed in relation to the meso (university administration) and the micro (academics) level. Inside the case study, participants from the university administration and academic levels were selected both via snow-ball technique and purposive selection, thus they had different levels of seniority, with some participating actively in the curriculum reform processes. Guided by an interpretivist approach to research, documents and interview transcripts were analyzed to reveal major themes emerging from the data. A further ‘bigger picture’ analysis guided by critical theory was then undertaken, involving interrogation of underlying ideologies and how political and economic interests influence the cultural production of policy. The case-study university was selected because it represents a traditional and old case of university setting in the country, undergoing curriculum changes based on international trends such as the competency model and the liberal arts. Also, it is representative of a particular socioeconomic sector of the country. Access to the university was gained through email contact. Qualitative research methods were used, namely interviews and analysis of institutional documents. In all, 18 people were interviewed. The number was defined by when the saturation criterion was met. Semi-structured interview schedules were based on the four research questions about influences, policy texts, policy enactment and longer-term outcomes. Triangulation of information was used for the analysis. While there was no intention to generalize the specific findings of the case study, the results of the research were used as a focus for engagement with broader themes, often evident in global higher education policy developments. The research results were organized around major themes in three of the four contexts of the ‘policy trajectory’. Regarding the context of influences and the context of policy text production, themes relate to hegemony exercised by first world countries’ universities in the higher education field, its associated neoliberal ideology, with accountability and the discourse of continuous improvement, the local responses to those pressures, and the value of interdisciplinarity. Finally, regarding the context of policy practices and effects (enactment), themes emerged around the impacts of the curriculum changes on university staff, students, and resistance amongst academics. The research concluded with a few recommendations that potentially provide ‘food for thought’ beyond the localized settings of this study, as well as possibilities for further research.

Keywords: Curriculum, policy, higher education, global-local dynamics.

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Authors: Reza Hossseynie, Amir Jafari

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This paper presents a method for steering velocity bounded mobile robots in environments with partially known stationary obstacles. The exact location of obstacles is unknown and only a probability distribution associated with the location of the obstacles is known. Kinematic model of a 2-wheeled differential drive robot is used as the model of mobile robot. The presented control strategy uses the Artificial Potential Field (APF) method for devising a desired direction of movement for the robot at each instant of time while the Constrained Directions Control (CDC) uses the generated direction to produce the control signals required for steering the robot. The location of each obstacle is considered to be the mean value of the 2D probability distribution and similarly, the magnitude of the electric charge in the APF is set as the trace of covariance matrix of the location probability distribution. The method not only captures the challenges of planning the path (i.e. probabilistic nature of the location of unknown obstacles), but it also addresses the output saturation which is considered to be an important issue from the control perspective. Moreover, velocity of the robot can be controlled during the steering. For example, the velocity of robot can be reduced in close vicinity of obstacles and target to ensure safety. Finally, the control strategy is simulated for different scenarios to show how the method can be put into practice.

Keywords: Steering, obstacle avoidance, mobile robots, constrained directions control, artificial potential field.

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Authors: S. Farid F. Mojtahedi, Ali Khosravi, Behnaz Naeimian, S. Adel A. Hosseini

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Land subsidence is a gradual settling or sudden sinking of the land surface from changes that take place underground. There are different causes of land subsidence; most notably, ground-water overdraft and severe weather conditions. Subsidence of the land surface due to ground water overdraft is caused by an increase in the intergranular pressure in unconsolidated aquifers, which results in a loss of buoyancy of solid particles in the zone dewatered by the falling water table and accordingly compaction of the aquifer. On the other hand, exploitation of underground water may result in significant changes in degree of saturation of soil layers above the water table, increasing the effective stress in these layers, and considerable soil settlements. This study focuses on estimation of soil moisture at surface using different methods. Specifically, different methods for the estimation of moisture content at the soil surface, as an important term to solve Richard’s equation and estimate soil moisture profile are presented, and their results are discussed through comparison with field measurements obtained from Yanco1 station in south-eastern Australia. Surface soil moisture is not easy to measure at the spatial scale of a catchment. Due to the heterogeneity of soil type, land use, and topography, surface soil moisture may change considerably in space and time.

Keywords: Artificial neural network, empirical method, remote sensing, surface soil moisture, unsaturated soil.

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Authors: Alexander N. Savostyanov, Tatiana A. Dolgorukova, Elena A. Esipenko, Mikhail S. Zaleshin, Margherita Malanchini, Anna V. Budakova, Alexander E. Saprygin, Tatiana A. Golovko, Yulia V. Kovas

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EEG correlates of mathematical and trait anxiety level were studied in 52 healthy Russian-speakers during execution of error-recognition tasks with lexical, arithmetic and algebraic conditions. Event-related spectral perturbations were used as a measure of brain activity. The ERSP plots revealed alpha/beta desynchronizations within a 500-3000 ms interval after task onset and slow-wave synchronization within an interval of 150-350 ms. Amplitudes of these intervals reflected the accuracy of error recognition, and were differently associated with the three conditions. The correlates of anxiety were found in theta (4-8 Hz) and beta2 (16- 20 Hz) frequency bands. In theta band the effects of mathematical anxiety were stronger expressed in lexical, than in arithmetic and algebraic condition. The mathematical anxiety effects in theta band were associated with differences between anterior and posterior cortical areas, whereas the effects of trait anxiety were associated with inter-hemispherical differences. In beta1 and beta2 bands effects of trait and mathematical anxiety were directed oppositely. The trait anxiety was associated with increase of amplitude of desynchronization, whereas the mathematical anxiety was associated with decrease of this amplitude. The effect of mathematical anxiety in beta2 band was insignificant for lexical condition but was the strongest in algebraic condition. EEG correlates of anxiety in theta band could be interpreted as indexes of task emotionality, whereas the reaction in beta2 band is related to tension of intellectual resources.

Keywords: EEG, brain activity, lexical and numerical error-recognition tasks, mathematical and trait anxiety.

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Authors: Ayşe Nihan Avcı, İpek Memikoğlu

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Lighting systems in interior architecture need to be designed according to the function of the space, the type of task within the space, user comfort and needs. Desired and comfortable lighting levels increase task efficiency. When natural lighting is inadequate in a space, artificial lighting is additionally used to support the level of light. With the technological developments, the characteristics of light are being researched comprehensively and several business segments have focused on its qualitative and quantitative characteristics. These studies have increased awareness and usage of artificial lighting systems and researchers have investigated the effects of lighting on physical and psychological aspects of human in various ways. The aim of this study is to research the effects of illuminance levels of LED lighting on user visual comfort. Eighty participants from the Department of Interior Architecture of Çankaya University participated in three lighting scenarios consisting of 200 lux, 500 lux and 800 lux that are created with LED lighting. Each lighting scenario is evaluated according to six visual comfort criteria in which a reading task is performed. The results of the study indicated that LED lighting with three different illuminance levels affect visual comfort in different ways. The results are limited to the participants and questions that are attended and used in this study.

Keywords: Illuminance levels, LED lighting, reading task, visual comfort criteria.

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Authors: Shaharin A. Sulaiman, Haizatul H. Hussain, Nik Siti H. Nik Leh, Mohd S. I. Razali

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Accumulation of dust from the outdoor environment on the panels of solar photovoltaic (PV) system is natural. There were studies that showed that the accumulated dust can reduce the performance of solar panels, but the results were not clearly quantified. The objective of this research was to study the effects of dust accumulation on the performance of solar PV panels. Experiments were conducted using dust particles on solar panels with a constant-power light source, to determine the resulting electrical power generated and efficiency. It was found from the study that the accumulated dust on the surface of photovoltaic solar panel can reduce the system-s efficiency by up to 50%.

Keywords: Dust, Photovoltaic, Solar Energy.

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Authors: Eunil Park, Angel P. del Pobil

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Does a communication modality matter in delivering e-learning information? With the recent growth of broadcasting systems, media technologies and e-learning contents, various systems with different communication modalities have been introduced. In accordance with these trends, this study examines the effects of the information delivery modality on psychology of students. Findings from an experiment indicated that the delivering information which includes a video modality elicited higher degrees of credibility, quality, representativeness of content, and perceived suitability for delivering information than those of auditory information. However, there is no difference between content liking and attitude. The Implications of the findings and the limitations are discussed.

Keywords: Communication modality, e-learning, multimodality, students.

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Authors: Saad M. Howladar, Ashraf Sh. Osman, Mostafa M. Rady, Hassan S. Al-Zahrani

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The effects of soil inoculation with phosphorien-containing phosphate-dissolving bacteria (PDB) and/or magnesium (Mg) foliar application at the rates of 0, 0.5 and 1mM on growth, green pod and seed yields, and chemical constituents of Pisum sativum L. grown on a sandy calcareous soil were investigated. Results indicated that PDB and/or Mg significantly increased shoot length, number of branches plant^–1, total leaf area plant^–1 and canopy dry weight plant^–1, leaf contents of pigments, soluble sugars, free proline, nitrogen, phosphorus, potassium, magnesium, and calcium, and Ca/Na ratio, while leaf Na content was reduced. PDB and/or Mg also increased green pod and seed yields. We concluded that PDB and Mg have pronounced positive effects on Pisum sativum L. plants grown on sandy calcareous soil. PDB and Mg, therefore, have the potential to be applied for various crops to overcome the adverse effects of the newly-reclaimed sandy calcareous soils.

Keywords: Bio-P-fertilizer, Mg foliar application, Newly-reclaimed soils, Pisum sativum L.

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Authors: George Yungchih Wang

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For decades financial economists have been attempted to determine the optimal investment policy by recognizing the option value embedded in irreversible investment whose project value evolves as a geometric Brownian motion (GBM). This paper aims to examine the effects of the optimal investment trigger and of the misspecification of stochastic processes on investment in real options applications. Specifically, the former explores the consequence of adopting optimal investment rules on the distributions of corporate value under the correct assumption of stochastic process while the latter analyzes the influence on the distributions of corporate value as a result of the misspecification of stochastic processes, i.e., mistaking an alternative process as a GBM. It is found that adopting the correct optimal investment policy may increase corporate value by shifting the value distribution rightward, and the misspecification effect may decrease corporate value by shifting the value distribution leftward. The adoption of the optimal investment trigger has a major impact on investment to such an extent that the downside risk of investment is truncated at the project value of zero, thereby moving the value distributions rightward. The analytical framework is also extended to situations where collection lags are in place, and the result indicates that collection lags reduce the effects of investment trigger and misspecification on investment in an opposite way.

Keywords: GBM, real options, investment trigger, misspecification, collection lags

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Authors: Hilal A. Fadhil, Thanaa Hussein Abd, Hamza M. R. Al-Khafaji, S. A. Aljunid

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This paper presents a comparison between Spectrum- Sliced Wavelength Division Multiplexing (SS-WDM) and Spectrum Amplitude Coding Optical Code Division Multiple Access (SAC Optical CDMA) systems for different light sources. The performance of the system is shown in the simulated results of the bit error rate (BER) and the eye diagram of both systems. The comparison results indicate that the Multiple Access Interference (MAI) effects have a significant impact on SS-WDM over SAC Optical CDMA systems. Finally, in terms of spectral efficiency at constant BER of 10-12, SSWDM offers higher spectral efficiency than optical CDMA since no bandwidth expansion in needed.

Keywords: WDM, OCDMA, BER, RD code

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Authors: Nazli Akhlaghinia, Ali Rajabzadeh Ghatari

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In today's world, with increasing environmental awareness, firms are facing severe pressure from various stakeholders, including the government and customers, to reduce their harmful effects on the environment. Over the past few decades, the increasing effects of global warming, climate change, waste, and air pollution have increased the global attention of experts to the issue of the green supply chain and led them to the optimal solution for greenery. Green supply chain management (GSCM) plays an important role in motivating the sustainability of the organization. With increasing environmental concerns, the main objective of the research is to use system thinking methodology and Vensim software for designing a dynamic system model for green supply chain and observing behaviors. Using this methodology, we look for the effects of a green supply chain structure on the behavioral dynamics of output variables. We try to simulate the complexity of GSCM in a period of 30 months and observe the complexity of behaviors of variables including sustainability, providing green products, and reducing energy consumption, and consequently reducing sample pollution.

Keywords: Supply chain management, green supply chain management, system dynamics, energy consumption.

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Authors: Kevin Fong-Rey Liu, Ken Yeh, Cheng-Wu Chen, Han-Hsi Liang

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The sanitary sewerage connection rate becomes an important indicator of advanced cities. Following the construction of sanitary sewerages, the maintenance and management systems are required for keeping pipelines and facilities functioning well. These maintenance tasks often require sewer workers to enter the manholes and the pipelines, which are confined spaces short of natural ventilation and full of hazardous substances. Working in sewers could be easily exposed to a risk of adverse health effects. This paper proposes the use of Bayesian belief networks (BBN) as a higher level of noncarcinogenic health risk assessment of sewer workers. On the basis of the epidemiological studies, the actual hospital attendance records and expert experiences, the BBN is capable of capturing the probabilistic relationships between the hazardous substances in sewers and their adverse health effects, and accordingly inferring the morbidity and mortality of the adverse health effects. The provision of the morbidity and mortality rates of the related diseases is more informative and can alleviate the drawbacks of conventional methods.

Keywords: Bayesian belief networks, sanitary sewerage, healthrisk assessment, hazard quotient, target organ-specific hazard index.

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Authors: Sh. Edrisi, A. Farahbakhsh

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An experiment was conducted under controlled conditions to study the effect of water extract of leaves, shoots and roots of either Sisymbrium irio L. =SISIR and or Descurainia sophia (L.) Schur =DESSO on the germination and primary growth of barley. A split-split plot experiment in CRD with three replications was used. The main plots were the type of weed: i.e. SISIR and DESSO and the sub-plots were type of organ: i.e. leaf, stem and root and, the sub-sub plots were concentration of the water extract of each organ of the weeds: i.e. 0, 2, 4 and 8 % w/v. The results showed that the SISIR water extracts had a greater inhibitory effects on the germination and primary growth of barley than those of DESSO water extracts. The water extracts of the leaves of both weeds had the greatest inhibitory effects on the germination and primary growth of barley, compared to those of stems and roots. Increasing the concentration of water extracts of leaves, stems and roots of both weeds up to 8 % caused the greatest inhibitory effects to barley and reduced the germination rate and primary growth of it linearly.

Keywords: Allelopathy, barley, DESSO, SISIR

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Authors: Anna Dolinayova, Jozef Danis, Juraj Camaj

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The report deals with comparison of traffic accidents in Slovak republic in road and rail transport since 2009 until 2014, with evaluation of external costs and consequently with the possibilities of their internalization. The results of road traffic accidents analysis are realized in line with after-effects they have caused; in line with main cause, place of origin (within or out of town) and in accordance to age of accident´s victims and kind of injuries (easy, hard or fatal). Evaluation of individual after-effects is carried in terms of probability of traffic accidents occurrence.

Keywords: External costs, traffic accident, rail transport, road transport.

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Authors: Sh. Edrisi, A. Farahbakhsh

Abstract:

An experiment was conducted under controlled conditions to study the effect of water extract of leaves, shoots and roots of either Sisymbrium irio L. =SISIR and/or Descurainia sophia (L.) Schur =DESSO on the germination and primary growth of wheat. A split-split plot experiment in CRD with three replications was used. The main plots were the type of weed: i.e. SISIR and DESSO and the sub-plots were type of organ: i.e. leaf, stem and root and, the sub-sub plots were concentration of the water extract of each organ of the weeds: i.e. 0, 2, 4 and 8 % w/v. The plant materials were cut in 2-3 cm pieces and then were ground in a blender. The crushed materials were weighed according to experimental protocol and the final volume was reached to 100 ml in distilled water in dark bottles. All bottles were put on a shaker for 24 hours. The solutions were filtered by muslin cloth. Whatman paper, 9 cm in diameter, were put in petri dishes and twenty seeds of wheat were put on it and 5 ml distilled water or water extract of weeds were added to each petri dish. All petri dishes were put in constant temperature of 15 0C incubator. The results showed that the SISIR water extract had a greater inhibitory effects on germination and primary growth of wheat than those of DESSO water extract. The water extracts of the leaves of both weeds had the greatest inhibitory effects on germination and primary growth of wheat, compared to those of stems and roots. Increasing the concentration of water extract of leaves, stems and roots of both weeds up to 8 % caused the greatest inhibitory effects to wheat and reduced the germination rate and primary growth of it linearly.

Keywords: Allelopathy, DESSO, SISIR, wheat

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Authors: Shuimiao Wan, Chao Yuan, Baoguang Tian

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In this paper, a linear mixed model which has two random effects is broken up into two models. This thesis gets the parameter estimation of the original model and an estimation’s statistical qualities based on these two models. Then many important properties are given by comparing this estimation with other general estimations. At the same time, this paper proves the analysis of variance estimate (ANOVAE) about σ2 of the original model is equal to the least-squares estimation (LSE) about σ2 of these two models. Finally, it also proves that this estimation is better than ANOVAE under Stein function and special condition in some degree.

Keywords: Linear mixed model, Random effects, Parameter estimation, Stein function.

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Authors: M. Bharath, Vasudevan Raghavan, B. V. S. S. S. Prasad, S. R. Chakravarthy

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In this experimental study, effects of addition of rice husk on coal gasification in a bubbling fluidized bed gasifier, operating at atmospheric pressure with air as gasifying agent, are reported. Rice husks comprising of 6.5% and 13% by mass are added to coal. Results show that, when rice husk is added the methane yield increases from volumetric percentage of 0.56% (with no rice husk) to 2.77% (with 13% rice husk). CO and H₂ remain almost unchanged and CO₂ decreases with addition of rice husk. The calorific value of the synthetic gas is around 2.73 MJ/Nm³. All performance indices, such as cold gas efficiency and carbon conversion, increase with addition of rice husk.

Keywords: Bubbling fluidized bed reactor, coal gasification, calorific value, rice husk.

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Authors: F. D. Konstandakopoulou, G. A. Papagiannopoulos, N. G. Pnevmatikos, G. D. Hatzigeorgiou

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This paper examines the effects of pile-soil-structure interaction on the dynamic response of offshore platforms under the action of near-fault earthquakes. Two offshore platforms models are investigated, one with completely fixed supports and one with piles which are clamped into deformable layered soil. The soil deformability for the second model is simulated using non-linear springs. These platform models are subjected to near-fault seismic ground motions. The role of fault mechanism on platforms’ response is additionally investigated, while the study also examines the effects of different angles of incidence of seismic records on the maximum response of each platform.

Keywords: Hazard analysis, offshore platforms, earthquakes, safety.

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Authors: S. Iffat, B. Bose

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Concrete as a construction material is versatile because it displays high degree of fire-resistance. Concrete’s inherent ability to combat one of the most devastating disaster that a structure can endure in its lifetime, can be attributed to its constituent materials which make it inert and have relatively poor thermal conductivity. However, concrete structures must be designed for fire effects. Structural components should be able to withstand dead and live loads without undergoing collapse. The properties of high-strength concrete must be weighed against concerns about its fire resistance and susceptibility to spalling at elevated temperatures. In this paper, the causes, effects and some remedy of deterioration in concrete due to fire hazard will be discussed. Some cost effective solutions to produce a fire resistant concrete will be conversed through this paper.

Keywords: Concrete, fire, spalling, temperature, compressive strength, density.

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Authors: Toni Raurich, Joan Llonch-Andreu

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This research focused on the relationship between Search Engine Marketing (SEM) and traditional advertising. The dominant assumption is that SEM does not help brand awareness and only does it in session as if it were the cost of manufacturing the product being sold. The study is methodologically developed using an experiment where the effects were determined to analyze the billboard effect. The research allowed the cross-linking of theoretical and empirical knowledge on digital marketing. This paper has validated that, this marketing generates retention as traditional advertising would by measuring brand awareness and its improvements. This changes the way performance and brand campaigns are distributed within marketing departments, effectively rebalancing budgets moving forward.

Keywords: Search engine marketing, click-through ratios, pay-per-click, marketing attribution.

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Authors: P. Sowa

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The article reviews the current state of large-scale studies about the impact of electromagnetic field on natural environment. The scenario of investigations – simulation of natural conditions at the workplace, taking into consideration the influence both low and high frequency electromagnetic fields is shown.The biological effects of low and high frequency electromagnetic fields are below presented. Results of investigation with animals are shown. The norms and regulations concerning the levels of electromagnetic field intensity are reviewed.

Keywords: Electromagnetic field and environment, biological effects of electric field on human body, simulation of natural condition at workplace

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Authors: B. E. Weber, N. Vrielink, M. G. Rietbergen

Abstract:

This paper explores the long-term effects of the Energy Box trajectory on households in the private rental sector, specifically households experiencing energy poverty. The concept of energy poverty has been getting increasing attention among policymakers over the past few years. In the Netherlands, as far as we know, there are no national policies on alleviating energy poverty, which negatively impacts energy-poor households. The Energy Box can help households experiencing energy poverty by stimulating them to improve the energy efficiency of their home by changing their energy-saving behavior. Important long-term effects are that respondents indicate that they live in a more environmentally friendly way and that they save money on their energy bills. Households feel engaged with the concept of energy-saving and can see the benefits of changing their energy-saving behavior. Respondents perceived the Energy Box as a means to live more environmentally friendly, instead of it solely being a means to save money on energy bills. The findings show that most respondents signed up for the Energy Box are interested in energy-saving as a lifestyle choice instead of a financial choice, which would likely be the case for households experiencing energy poverty.

Keywords: Energy-saving behavior, energy poverty, poverty, private rental sector.

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Authors: Ehi E. Aimiuwu

Abstract:

As of 2017, many online learning professionals, institutions, and journals are still wondering how instructors can keep student engaged in the online learning environment to facilitate active learning effectively. The purpose of this qualitative single-case and narrative research is to explore whether online professors understand their role as mentors and facilitators of students’ academic success by keeping students engaged in active learning based on personalized experience in the field. Data collection tools that were used in the study included an NVivo 12 Plus qualitative software, an interview protocol, a digital audiotape, an observation sheet, and a transcription. Seven online professors in the United States from LinkedIn and residencies were interviewed for this study. Eleven online teaching techniques from previous research were used as the study framework. Data analysis process, member checking, and key themes were used to achieve saturation. About 85.7% of professors agreed on rubric as the preferred online grading technique. About 57.1% agreed on professors logging in daily, students logging in about 2-5 times weekly, knowing students to increase accountability, email as preferred communication tool, and computer access for adequate online learning. About 42.9% agreed on syllabus for clear class expectations, participation to show what has been learned, and energizing students for creativity.

Keywords: Class facilitation, class management, online teaching, online education, pedagogy.

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