Search results for: phase transition.
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1934

Search results for: phase transition.

1034 Modeling Aggregation of Insoluble Phase in Reactors

Authors: A. Brener, B. Ismailov, G. Berdalieva

Abstract:

In the paper we submit the modification of kinetic Smoluchowski equation for binary aggregation applying to systems with chemical reactions of first and second orders in which the main product is insoluble. The goal of this work is to create theoretical foundation and engineering procedures for calculating the chemical apparatuses in the conditions of joint course of chemical reactions and processes of aggregation of insoluble dispersed phases which are formed in working zones of the reactor.

Keywords: Binary aggregation, Clusters, Chemical reactions, Insoluble phases.

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1033 Predictive Clustering Hybrid Regression(pCHR) Approach and Its Application to Sucrose-Based Biohydrogen Production

Authors: Nikhil, Ari Visa, Chin-Chao Chen, Chiu-Yue Lin, Jaakko A. Puhakka, Olli Yli-Harja

Abstract:

A predictive clustering hybrid regression (pCHR) approach was developed and evaluated using dataset from H2- producing sucrose-based bioreactor operated for 15 months. The aim was to model and predict the H2-production rate using information available about envirome and metabolome of the bioprocess. Selforganizing maps (SOM) and Sammon map were used to visualize the dataset and to identify main metabolic patterns and clusters in bioprocess data. Three metabolic clusters: acetate coupled with other metabolites, butyrate only, and transition phases were detected. The developed pCHR model combines principles of k-means clustering, kNN classification and regression techniques. The model performed well in modeling and predicting the H2-production rate with mean square error values of 0.0014 and 0.0032, respectively.

Keywords: Biohydrogen, bioprocess modeling, clusteringhybrid regression.

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1032 Development of Single Layer of WO3 on Large Spatial Resolution by Atomic Layer Deposition Technique

Authors: S. Zhuiykov, Zh. Hai, H. Xu, C. Xue

Abstract:

Unique and distinctive properties could be obtained on such two-dimensional (2D) semiconductor as tungsten trioxide (WO3) when the reduction from multi-layer to one fundamental layer thickness takes place. This transition without damaging single-layer on a large spatial resolution remained elusive until the atomic layer deposition (ALD) technique was utilized. Here we report the ALD-enabled atomic-layer-precision development of a single layer WO3 with thickness of 0.77±0.07 nm on a large spatial resolution by using (tBuN)2W(NMe2)2 as tungsten precursor and H2O as oxygen precursor, without affecting the underlying SiO2/Si substrate. Versatility of ALD is in tuning recipe in order to achieve the complete WO3 with desired number of WO3 layers including monolayer. Governed by self-limiting surface reactions, the ALD-enabled approach is versatile, scalable and applicable for a broader range of 2D semiconductors and various device applications.

Keywords: Atomic layer deposition, tungsten oxide, WO3, two-dimensional semiconductors, single fundamental layer.

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1031 Do Persistent and Transitory Hybrid Entrepreneurs Differ?

Authors: Anmari H. Viljamaa, Elina M. Varamäki

Abstract:

In this study, we compare the profiles of transitory hybrid entrepreneurs and persistent hybrid entrepreneurs to determine how they differ. Hybrid entrepreneurs (HEs) represent a significant share of entrepreneurial activity yet little is known about them. We define HEs as individuals who are active as entrepreneurs but do no support themselves primarily by their enterprise. Persistent HEs (PHEs) are not planning to transition to fulltime entrepreneurship whereas transitory HEs (THEs) consider it probable. Our results show that THEs and PHEs are quite similar in background. THEs are more interested in increasing their turnover than PHEs, as expected, but also emphasize self-fulfillment as a motive for entrepreneurship more than PHEs. The clearest differences between THEs and PHEs are found in their views on how well their immediate circle supports full-time entrepreneurship, and their views of their own entrepreneurial abilities and the market potential of their firm. Our results support earlier arguments that hybrids should be considered separately in research on entrepreneurial entry and self-employment.

Keywords: Hybrid entrepreneurship, part-time entrepreneurship, self-employment, Theory of Planned Behavior.

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1030 Political and Economic Transition of People with Disabilities Related to Globalization

Authors: Jihye Jeon

Abstract:

This paper analyzes the political and economic issues that people with disabilities face related to globalization; how people with disabilities have been adapting globalization and surviving under worldwide competition system. It explains that economic globalization exacerbates inequality and deprivation of people with disabilities. The rising tide of neo-liberal welfare policies emphasized efficiency, downsized social expenditure for people with disabilities, excluded people with disabilities against labor market, and shifted them from welfare system to nothing. However, there have been people with disabilities' political responses to globalization, which are characterized by a global network of people with disabilities as well as participation to global governance. Their resistance can be seen as an attempt to tackle the problems that economic globalization has produced. It is necessary paradigm shift of disability policy from dependency represented by disability benefits to independency represented by labor market policies for people with disabilities.

Keywords: Economic Globalization, People with Disability, Deprivation, Welfare Cut, Disability Right Movement, Resistance.

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1029 Support Services for Students with Special Education Needs in Colleges and Universities

Authors: Hsiu-Fen Chen, Fang-Liu Su, Ya-Wen Chang

Abstract:

purpose of this study was to investigate the current status of support services for students with special education needs (SEN) at colleges and universities in Taiwan. Seventy-two college and universities received a questionnaire on its resource room operation process and four resource room staffs each from different areas were interviewed through semi- structured interview forms. The main findings were (1) most colleges and universities did offer sufficient administrative resources; (2) more efforts on preventions for SEN students and establishment of disability awareness should be made for all campus faculties ; (3) more comprehensive services were required to help students to have better transition into post-school life; (4) most schools provided basic administrative resource requirements but qualities of the resource room programs needed to be enhanced; and (5) most resource room staffs lacked of professional knowledge in counseling the SEN students which needed to be strengthened in the future.

Keywords: support services, students with special education needs, higher education, resource room program

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1028 Adaptation of State/Transition-Based Methods for Embedded System Testing

Authors: Abdelaziz Guerrouat, Harald Richter

Abstract:

In this paper test generation methods and appropriate fault models for testing and analysis of embedded systems described as (extended) finite state machines ((E)FSMs) are presented. Compared to simple FSMs, EFSMs specify not only the control flow but also the data flow. Thus, we define a two-level fault model to cover both aspects. The goal of this paper is to reuse well-known FSM-based test generation methods for automation of embedded system testing. These methods have been widely used in testing and validation of protocols and communicating systems. In particular, (E)FSMs-based specification and testing is more advantageous because (E)FSMs support the formal semantic of already standardised formal description techniques (FDTs) despite of their popularity in the design of hardware and software systems.

Keywords: Formal methods, testing and validation, finite state machines, formal description techniques.

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1027 Multitasking Trends and Impact on Education: A Literature Review

Authors: Mohammed Alkahtani, Ali Ahmad, Saber Darmoul, Shatha Samman, Ayoub Al-zabidi, Khaled Ba Matraf

Abstract:

Education systems are complex and involve interactions between humans (teachers and students); media based technologies, lectures, classrooms, etc. to provide educational services. The education system performance is characterized by how well students learn, which is measured using student grades on exams and quizzes, achievements on standardized tests, among others. Advances in portable communications technologies, such as mobile phones, tablets, and laptops, created a different type of classroom, where students seem to engage in more than just the intended learning activities. The performance of more than one task in parallel or in rapid transition is commonly known as multitasking. Several operations in educational systems are performed simultaneously, resulting in a multitasking education environment. This paper surveys existing research on multitasking in educational settings, summarizes literature findings, provides a synthesis of the impact of multitasking on performance, and identifies directions of future research.

Keywords: Education systems, GPA, multitasking, performance.

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1026 A Study on How Newlyweds Handle the Difference with Parents on Wedding Arrangements and Its Implication for Services in Hong Kong

Authors: K. M. Yuen

Abstract:

This research examined the literature review of wedding preparation’s challenges and its developmental tasks of family transition under family life cycle. Five interviewees were invited to share their experiences on the differences with their parents in regard to wedding preparations and coping strategies. Some coping strategies and processes were highlighted for facilitating the family to achieve the developmental tasks during the wedding preparation. However, those coping strategies and processes may only act as the step and the behavior, while “concern towards parents” was found to be the essential element behind these behaviors. In addition to pre-marital counseling, a developmental group was suggested to develop under the framework of family life cycle and its related coping strategies on working with the newlyweds who encountered intergenerational differences in regard to their wedding preparations.

Keywords: Coping strategies, difference, family life cycle, developmental tasks, wedding preparation.

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1025 Tropical Cyclogenesis Response to Solar Activity in the Eastern Pacific Region

Authors: Marni Pazos, Blanca Mendoza, Luis Gimeno

Abstract:

The relationship between tropical cyclogenesis and solar activity is addressed in this paper, analyzing the relationship between important parameters in the evolution of tropical cyclones as the CAPE, wind shear and relative vorticity, and the Dst geomagnetic index as a parameter of solar activity. The apparent relationship between all this phenomena has a different response depending on the phase of the solar cycles.

Keywords: tropical cyclones, solar-earth relationship, climate change.

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1024 Using Strategic CSR to Achieve the Hybrid Middle Ground in Social Entrepreneurship: The Case of Telenor Hungary

Authors: Peter Hardi, Bala Mulloth

Abstract:

To be considered a socially entrepreneurial organization today requires achieving what can be termed a “hybrid middle ground” equilibrium, comprising of economic as well as social sustainability. This middle ground requires some blend of both business and social commitments. In this paper, we use the case of Hungary's second ranked mobile operator, Telenor Hungary to illustrate an example of a company that is moving to the hybrid middle ground by transitioning from a for-profit company to a socially responsible business using the concept of strategic CSR. In this line of thinking, the organization explicitly supports programs and initiatives that have a direct link to the core business and bring operational and/or financial advantages for the company, while creating a positive social and/or environmental impact. The important lessons learned from the company transition are also discussed. 

Keywords: Hybrid middle ground, social entrepreneurship, strategic corporate social responsibility.

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1023 Simulation of the Extensional Flow Mixing of Molten Aluminium and Fly Ash Nanoparticles

Authors: O. Ualibek, C. Spitas, V. Inglezakis, G. Itskos

Abstract:

This study presents simulations of an aluminium melt containing an initially non-dispersed fly ash nanoparticle phase. Mixing is affected predominantly by means of forced extensional flow via either straight or slanted orifices. The sensitivity to various process parameters is determined. The simulated process is used for the production of cast fly ash-aluminium nanocomposites. The possibilities for rod and plate stock grading in the context of a continuous casting process implementation are discussed.

Keywords: Metal matrix composites, fly ash nanoparticles, aluminium 2024, agglomeration.

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1022 Inductive Grammar, Student-Centered Reading, and Interactive Poetry: The Effects of Teaching English with Fun in Schools of Two Villages in Lebanon

Authors: Talar Agopian

Abstract:

Teaching English as a Second Language (ESL) is a common practice in many Lebanese schools. However, ESL teaching is done in traditional ways. Methods such as constructivism are seldom used, especially in villages. Here lies the significance of this research which joins constructivism and Piaget’s theory of cognitive development in ESL classes in Lebanese villages. The purpose of the present study is to explore the effects of applying constructivist student-centered strategies in teaching grammar, reading comprehension, and poetry on students in elementary ESL classes in two villages in Lebanon, Zefta in South Lebanon and Boqaata in Mount Lebanon. 20 English teachers participated in a training titled “Teaching English with Fun”, which focused on strategies that create a student-centered class where active learning takes place and there is increased learner engagement and autonomy. The training covered three main areas in teaching English: grammar, reading comprehension, and poetry. After participating in the training, the teachers applied the new strategies and methods in their ESL classes. The methodology comprised two phases: in phase one, practice-based research was conducted as the teachers attended the training and applied the constructivist strategies in their respective ESL classes. Phase two included the reflections of the teachers on the effects of the application of constructivist strategies. The results revealed the educational benefits of constructivist student-centered strategies; the students of teachers who applied these strategies showed improved engagement, positive attitudes towards poetry, increased motivation, and a better sense of autonomy. Future research is required in applying constructivist methods in the areas of writing, spelling, and vocabulary in ESL classrooms of Lebanese villages.

Keywords: Active learning, constructivism, learner engagement, student-centered strategies.

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1021 In Search of Innovation: Exploring the Dynamics of Innovation

Authors: Michal Lysek, Mike Danilovic, Jasmine Lihua Liu

Abstract:

HMS Industrial Networks AB has been recognized as one of the most innovative companies in the industrial communication industry worldwide. The creation of their Anybus innovation during the 1990s contributed considerably to the company’s success. From inception, HMS’ employees were innovating for the purpose of creating new business (the creation phase). After the Anybus innovation, they began the process of internationalization (the commercialization phase), which in turn led them to concentrate on cost reduction, product quality, delivery precision, operational efficiency, and increasing growth (the growth phase). As a result of this transformation, performing new radical innovations have become more complicated. The purpose of our research was to explore the dynamics of innovation at HMS from the aspect of key actors, activities, and events, over the three phases, in order to understand what led to the creation of their Anybus innovation, and why it has become increasingly challenging for HMS to create new radical innovations for the future. Our research methodology was based on a longitudinal, retrospective study from the inception of HMS in 1988 to 2014, a single case study inspired by the grounded theory approach. We conducted 47 interviews and collected 1 024 historical documents for our research. Our analysis has revealed that HMS’ success in creating the Anybus, and developing a successful business around the innovation, was based on three main capabilities – cultivating customer relations on different managerial and organizational levels, inspiring business relations, and balancing complementary human assets for the purpose of business creation. The success of HMS has turned the management’s attention away from past activities of key actors, of their behavior, and how they influenced and stimulated the creation of radical innovations. Nowadays, they are rhetorically focusing on creativity and innovation. All the while, their real actions put emphasis on growth, cost reduction, product quality, delivery precision, operational efficiency, and moneymaking. In the process of becoming an international company, HMS gradually refocused. In so doing they became profitable and successful, but they also forgot what made them innovative in the first place. Fortunately, HMS’ management has come to realize that this is the case and they are now in search of recapturing innovation once again. Our analysis indicates that HMS’ management is facing several barriers to innovation related path dependency and other lock-in phenomena. HMS’ management has been captured, trapped in their mindset and actions, by the success of the past. But now their future has to be secured, and they have come to realize that moneymaking is not everything. In recent years, HMS’ management have begun to search for innovation once more, in order to recapture their past capabilities for creating radical innovations. In order to unlock their managerial perceptions of customer needs and their counter-innovation driven activities and events, to utilize the full potential of their employees and capture the innovation opportunity for the future.

Keywords: Barriers to innovation, dynamics of innovation, in search of excellence and innovation, radical innovation.

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1020 Shot Transition Detection with Minimal Decoding of MPEG Video Streams

Authors: Mona A. Fouad, Fatma M. Bayoumi, Hoda M. Onsi, Mohamed G. Darwish

Abstract:

Digital libraries become more and more necessary in order to support users with powerful and easy-to-use tools for searching, browsing and retrieving media information. The starting point for these tasks is the segmentation of video content into shots. To segment MPEG video streams into shots, a fully automatic procedure to detect both abrupt and gradual transitions (dissolve and fade-groups) with minimal decoding in real time is developed in this study. Each was explored through two phases: macro-block type's analysis in B-frames, and on-demand intensity information analysis. The experimental results show remarkable performance in detecting gradual transitions of some kinds of input data and comparable results of the rest of the examined video streams. Almost all abrupt transitions could be detected with very few false positive alarms.

Keywords: Adaptive threshold, abrupt transitions, gradual transitions, MPEG video streams.

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1019 Institutional Determinants of Economic Growth in Georgia and in Other Post-Communist Economies

Authors: Nazira Kakulia, Tsotne Zhghenti

Abstract:

The institutional development is one of the actual topics in economics science. New trends and directions of institutional development mostly depend on its structure and framework. Transformation of institutions is an important problem for every economy, especially for developing countries. The first research goal is to determine the importance and interactions between different institutions in Georgia. Using World Governance Indicators and Economic Freedom indexes it can be calculated the size for each institutional group. The second aim of this research is to evaluate Georgian institutional backwardness in comparison to other post-communist economies. We use statistical and econometric methods to evaluate the difference between the levels of institutional development in Georgia and in leading post-communist economies. Within the scope of this research, major findings are coefficients which are an assessment of their deviation (i.e. lag) of institutional indicators between Georgia and leading post-communist country which should be compared. The last part of the article includes analysis around the selected coefficients.

Keywords: Post-communist transition, institutions, economic growth, institutional development.

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1018 Unsteady Free Convection Flow Over a Three-Dimensional Stagnation Point With Internal Heat Generation or Absorption

Authors: Mohd Ariff Admon, Abdul Rahman Mohd Kasim, Sharidan Shafie

Abstract:

This paper considers the effect of heat generation proportional l to (T - T∞ )p , where T is the local temperature and T∞ is the ambient temperature, in unsteady free convection flow near the stagnation point region of a three-dimensional body. The fluid is considered in an ambient fluid under the assumption of a step change in the surface temperature of the body. The non-linear coupled partial differential equations governing the free convection flow are solved numerically using an implicit finite-difference method for different values of the governing parameters entering these equations. The results for the flow and heat characteristics when p ≤ 2 show that the transition from the initial unsteady-state flow to the final steadystate flow takes place smoothly. The behavior of the flow is seen strongly depend on the exponent p.

Keywords: Free convection, Boundary layer flow, Stagnationpoint, Heat generation

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1017 Soil Moisture Regulation in Irrigated Agriculture

Authors: I. Kruashvili, I. Inashvili, K. Bziava, M. Lomishvili

Abstract:

Seepage capillary anomalies in the active layer of soil, related to the soil water movement, often cause variation of soil hydrophysical properties and become one of the main objectives of the hydroecology. It is necessary to mention that all existing equations for computing the seepage flow particularly from soil channels, through dams, bulkheads, and foundations of hydraulic engineering structures are preferable based on the linear seepage law. Regarding the existing beliefs, anomalous seepage is based on postulates according to which the fluid in free volume is characterized by resistance against shear deformation and is presented in the form of initial gradient. According to the above-mentioned information, we have determined: Equation to calculate seepage coefficient when the velocity of transition flow is equal to seepage flow velocity; by means of power function, equations for the calculation of average and maximum velocities of seepage flow have been derived; taking into consideration the fluid continuity condition, average velocity for calculation of average velocity in capillary tube has been received.

Keywords: Seepage, soil, velocity, water.

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1016 Green Prossesing of PS/Nanoparticle Fibers and Studying Morphology and Properties

Authors: M. Kheirandish, S. Borhani

Abstract:

In this experiment Polystyrene/Zinc-oxide (PS/ZnO) nanocomposite fibers were produced by electrospinning technique using limonene as a green solvent. First, the morphology of electrospun pure polystyrene (PS) and PS/ZnO nanocomposite fibers investigated by SEM. Results showed the PS fiber diameter decreased by increasing concentration of Zinc Oxide nanoparticles (ZnO NPs). Thermo Gravimetric Analysis (TGA) results showed thermal stability of nanocomposites increased by increasing ZnO NPs in PS electrospun fibers. Considering Differential Scanning Calorimeter (DSC) thermograms for electrospun PS fibers indicated that introduction of ZnO NPs into fibers affects the glass transition temperature (Tg) by reducing it. Also, UV protection properties of nanocomposite fibers were increased by increasing ZnO concentration. Evaluating the effect of metal oxide NPs amount on mechanical properties of electrospun layer showed that tensile strength and elasticity modulus of the electrospun layer of PS increased by addition of ZnO NPs. X-ray diffraction (XRD) pattern of nanopcomposite fibers confirmed the presence of NPs in the samples.

Keywords: Electrospininng, nanoparticle, polystyrene, ZnO.

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1015 Abai Kunanbayev's Role in Enrichment of the Kazakh Language

Authors: Y.M. Paltore, B.N. Zhubatova, A.A. Mustafayeva

Abstract:

Abai Kunanbayev is famous for being enlightener, composer, interpreter, social agent, philosopher, reformer, who wanted to enrich Kazakh literature by emergence with Russian and European culture, and also as a founder of Kazakh written literary language. Abai Kunanbayev was born in 1845 in East Kazakhstan area and passed away in 1904 in his hometown. His oeuvre absorbed and reflected all changes in the life of Kazakh society of the second half of XIX century. Because ХІХ century, especially its second half, was an important transition period for Kazakhstan, which radically changed traditional way of Kazakh society and predetermined further development in consequence of activation of Russian colonial policy and approval of commodity-money relations in Steppe Land.Abai Kunanbayev, besides Arabic and Persian common words and loanwords from Quran in his words of edification, had used a lot of words of Arabic, Persian, Latin, Russian, Nogai, Shaghatai, Polish, Greek, Turkish, which are used in the Kazakh language.

Keywords: Abai Kunanbayev, the Kazakh, Russian languages, literature

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1014 Active Power Filter dimensioning Using a Hysteresis Current Controller

Authors: Tarek A. Kasmieh, Hassan S. Omran

Abstract:

This paper aims to give a full study of the dynamic behavior of a mono-phase active power filter. First, the principle of the parallel active power filter will be introduced. Then, a dimensioning procedure for all its components will be explained in detail, such as the input filter, the current and voltage controllers. This active power filter is simulated using OrCAD program showing the validity of the theoretical study.

Keywords: Active power filter, Power Quality, Hysteresiscurrent controller.

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1013 A Spatial Repetitive Controller Applied to an Aeroelastic Model for Wind Turbines

Authors: Riccardo Fratini, Riccardo Santini, Jacopo Serafini, Massimo Gennaretti, Stefano Panzieri

Abstract:

This paper presents a nonlinear differential model, for a three-bladed horizontal axis wind turbine (HAWT) suited for control applications. It is based on a 8-dofs, lumped parameters structural dynamics coupled with a quasi-steady sectional aerodynamics. In particular, using the Euler-Lagrange Equation (Energetic Variation approach), the authors derive, and successively validate, such model. For the derivation of the aerodynamic model, the Greenbergs theory, an extension of the theory proposed by Theodorsen to the case of thin airfoils undergoing pulsating flows, is used. Specifically, in this work, the authors restricted that theory under the hypothesis of low perturbation reduced frequency k, which causes the lift deficiency function C(k) to be real and equal to 1. Furthermore, the expressions of the aerodynamic loads are obtained using the quasi-steady strip theory (Hodges and Ormiston), as a function of the chordwise and normal components of relative velocity between flow and airfoil Ut, Up, their derivatives, and section angular velocity ε˙. For the validation of the proposed model, the authors carried out open and closed-loop simulations of a 5 MW HAWT, characterized by radius R =61.5 m and by mean chord c = 3 m, with a nominal angular velocity Ωn = 1.266rad/sec. The first analysis performed is the steady state solution, where a uniform wind Vw = 11.4 m/s is considered and a collective pitch angle θ = 0.88◦ is imposed. During this step, the authors noticed that the proposed model is intrinsically periodic due to the effect of the wind and of the gravitational force. In order to reject this periodic trend in the model dynamics, the authors propose a collective repetitive control algorithm coupled with a PD controller. In particular, when the reference command to be tracked and/or the disturbance to be rejected are periodic signals with a fixed period, the repetitive control strategies can be applied due to their high precision, simple implementation and little performance dependency on system parameters. The functional scheme of a repetitive controller is quite simple and, given a periodic reference command, is composed of a control block Crc(s) usually added to an existing feedback control system. The control block contains and a free time-delay system eτs in a positive feedback loop, and a low-pass filter q(s). It should be noticed that, while the time delay term reduces the stability margin, on the other hand the low pass filter is added to ensure stability. It is worth noting that, in this work, the authors propose a phase shifting for the controller and the delay system has been modified as e^(−(T−γk)), where T is the period of the signal and γk is a phase shifting of k samples of the same periodic signal. It should be noticed that, the phase shifting technique is particularly useful in non-minimum phase systems, such as flexible structures. In fact, using the phase shifting, the iterative algorithm could reach the convergence also at high frequencies. Notice that, in our case study, the shifting of k samples depends both on the rotor angular velocity Ω and on the rotor azimuth angle Ψ: we refer to this controller as a spatial repetitive controller. The collective repetitive controller has also been coupled with a C(s) = PD(s), in order to dampen oscillations of the blades. The performance of the spatial repetitive controller is compared with an industrial PI controller. In particular, starting from wind speed velocity Vw = 11.4 m/s the controller is asked to maintain the nominal angular velocity Ωn = 1.266rad/s after an instantaneous increase of wind speed (Vw = 15 m/s). Then, a purely periodic external disturbance is introduced in order to stress the capabilities of the repetitive controller. The results of the simulations show that, contrary to a simple PI controller, the spatial repetitive-PD controller has the capability to reject both external disturbances and periodic trend in the model dynamics. Finally, the nominal value of the angular velocity is reached, in accordance with results obtained with commercial software for a turbine of the same type.

Keywords: Wind turbines, aeroelasticity, repetitive control, periodic systems.

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1012 A Survey on Lossless Compression of Bayer Color Filter Array Images

Authors: Alina Trifan, António J. R. Neves

Abstract:

Although most digital cameras acquire images in a raw format, based on a Color Filter Array that arranges RGB color filters on a square grid of photosensors, most image compression techniques do not use the raw data; instead, they use the rgb result of an interpolation algorithm of the raw data. This approach is inefficient and by performing a lossless compression of the raw data, followed by pixel interpolation, digital cameras could be more power efficient and provide images with increased resolution given that the interpolation step could be shifted to an external processing unit. In this paper, we conduct a survey on the use of lossless compression algorithms with raw Bayer images. Moreover, in order to reduce the effect of the transition between colors that increase the entropy of the raw Bayer image, we split the image into three new images corresponding to each channel (red, green and blue) and we study the same compression algorithms applied to each one individually. This simple pre-processing stage allows an improvement of more than 15% in predictive based methods.

Keywords: Bayer images, CFA, losseless compression, image coding standards.

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1011 Dynamic Model of Automatic Loom on SimulationX

Authors: A. Jomartov, A. Tuleshov, B. Tultaev

Abstract:

One of the main tasks in the development of textile machinery is to increase the rapidity of automatic looms, and consequently, their productivity. With increasing automatic loom speeds, the dynamic loads on their separate mechanisms and moving joints sharply increase. Dynamic research allows us to determine the weakest mechanisms of the automatic loom. The modern automatic loom consists of a large number of structurally different mechanisms. These are cam, lever, gear, friction and combined cyclic mechanisms. The modern automatic loom contains various mechatronic devices: A device for the automatic removal of faulty weft, electromechanical drive warp yarns, electronic controllers, servos, etc. In the paper, we consider the multibody dynamic model of the automatic loom on the software complex SimulationX. SimulationX is multidisciplinary software for modeling complex physical and technical facilities and systems. The multibody dynamic model of the automatic loom allows consideration of: The transition processes, backlash at the joints and nodes, the force of resistance and electric motor performance.

Keywords: Automatic loom, dynamics, model, multibody, SimulationX.

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1010 Mindfulness and Employability: A Course on the Control of Stress during the Search for Work

Authors: O. Lasaga

Abstract:

Defining professional objectives and the search for work are some of the greatest stress factors for final year university students and recent graduates. To manage correctly the stress brought about by the uncertainty, confusion and frustration this process often generates, a course to control stress based on mindfulness has been designed and taught. This course provides tools based on relaxation, mindfulness and meditation that enable students to address personal and professional challenges in the transition to the job market, eliminating or easing the anxiety involved. The course is extremely practical and experiential, combining theory classes and practical classes of relaxation, meditation and mindfulness, group dynamics, reflection, application protocols and session integration. The evaluation of the courses highlighted on the one hand the high degree of satisfaction and, on the other, the usefulness for the students in becoming aware of stressful situations and how these affect them and learning new coping techniques that enable them to reach their goals more easily and with greater satisfaction and well-being.

Keywords: Employability, meditation, mindfulness, relaxation techniques, stress.

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1009 Technology Roadmapping in Defense Industry

Authors: Sevgi Özlem Bulu, Arif Furkan Mendi, Tolga Erol, İzzet Gökhan Özbilgin

Abstract:

The rapid progress of technology in today's competitive conditions has also accelerated companies' technology development activities. As a result, companies are paying more attention to R&D studies and are beginning to allocate a larger share to R&D projects. A more systematic, comprehensive, target-oriented implementation of R&D studies is crucial for the company to achieve successful results. As a consequence, Technology Roadmap (TRM) is gaining importance as a management tool. It has critical prospects for achieving medium and long term success as it contains decisions about past business, future plans, technological infrastructure. When studies on TRM are examined, projects to be placed on the roadmap are selected by many different methods. Generally preferred methods are based on multi-criteria decision making methods. Management of selected projects becomes an important point after the selection phase of the projects. At this stage, TRM are used. TRM can be created in many different ways so that each institution can prepare its own Technology Roadmap according to their strategic plan. Depending on the intended use, there can be TRM with different layers at different sizes. In the evaluation phase of the R&D projects and in the creation of the TRM, HAVELSAN, Turkey's largest defense company in the software field, carries out this process with great care and diligence. At the beginning, suggested R&D projects are evaluated by the Technology Management Board (TMB) of HAVELSAN in accordance with the company's resources, objectives, and targets. These projects are presented to the TMB periodically for evaluation within the framework of certain criteria by board members. After the necessary steps have been passed, the approved projects are added to the time-based TRM, which is composed of four layers as market, product, project and technology. The use of a four-layered roadmap provides a clearer understanding and visualization of company strategy and objectives. This study demonstrates the benefits of using TRM, four-layered Technology Roadmapping and the possibilities for the institutions in the defense industry.

Keywords: Project selection, R&D in defense industry, R&D project selection, technology roadmapping.

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1008 An Improved Preprocessing for Biosonar Target Classification

Authors: Turgay Temel, John Hallam

Abstract:

An improved processing description to be employed in biosonar signal processing in a cochlea model is proposed and examined. It is compared to conventional models using a modified discrimination analysis and both are tested. Their performances are evaluated with echo data captured from natural targets (trees).Results indicate that the phase characteristics of low-pass filters employed in the echo processing have a significant effect on class separability for this data.

Keywords: Cochlea model, discriminant analysis, neurospikecoding, classification.

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1007 The Turkish Version of Inventory of the Dimensions of Emerging Adulthood(The IDEA)

Authors: Hasan Atak, Figen Çok

Abstract:

Emerging Adulthood, the period during ages 18 to 25, is a new conceptualitation proposed by Arnett which is especially prevalent in the industrialized countries. Turkey is basically a developing country having a young population structure. Investigating the presence of such a life period in such a culture might be helpful in understanding educational and psychological needs of people who are in their twenties. With the aim of investigating Emerging Adulthood in Turkey, a well-known instrument (IDEA, 2003) was adapted to Turkish language and Turkish culture. The scale was administered to 296 participants between 15 and 34 ages and validity and reliability were conducted. Exploratory factor analysis revealed three subscales. Reliability coefficients of the scale (Cronbach a) was found as .69. Test-retest reliability coefficients was found for the scale as .81. Finally, “The IDEA" with 20 items was obtained to be used in the Turkish population. The instrument is ready to be administered among Turkish young people for the investigation of transition to adulthood, and whether such a emerging adulthood period really existed.

Keywords: Adaptation, Emerging Adulthood, Turkey, IDEA.

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1006 A Foresight into Green Housing Industry in Malaysia

Authors: N. Zainul Abidin, N. Yusof, H. Awang

Abstract:

Bringing change to the housing industry requires multiple efforts from various angles especially to overcome any resistances in the form of technology, human aspects, financial and resources. The transition from conventional to sustainable approach consumes time as it requires changes from different facets in the industry ranging from individual, organisational to industry level. In Malaysia, there are various efforts to bring green into the industry but the progress is low-moderate. Will the current efforts bear larger fruits in the near future? This study examines the perceptions of the developers in Malaysia on the future of the green housing sector for the next 5 years. The introduction of GBI rating system, improvement of awareness and knowledge among the stakeholders, support from the government and local industry and the effect of competitive advantage would support brighter future. Meanwhile, the status quo in rules and regulation, lack of public interest and demand, organization disinterest, local authority enforcement and project cost escalation would hinder a faster progress.

Keywords: Developers, Green Concept, Housing Industry, Sustainable Construction

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1005 Integration of LCA and BIM for Sustainable Construction

Authors: Laura Álvarez Antón, Joaquín Díaz

Abstract:

The construction industry is turning towards sustainability. It is a well-known fact that sustainability is based on a balance between environmental, social and economic aspects. In order to achieve sustainability efficiently, these three criteria should be taken into account in the initial project phases, since that is when a project can be influenced most effectively. Thus the aim must be to integrate important tools like BIM and LCA at an early stage in order to make full use of their potential. With the synergies resulting from the integration of BIM and LCA, a wider approach to sustainability becomes possible, covering the three pillars of sustainability.

Keywords: Building Information Modeling (BIM), Construction Industry, Design Phase, Life Cycle Assessment (LCA), Sustainability.

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