Search results for: integral transformation

Authors: Beata Jackowska-Zduniak

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We formulate and analyze a mathematical model describing dynamics of cancer growth under the influence of radiation therapy. The effect of this type of therapy is considered as an additional equation of discussed model. Numerical simulations show that delay, which is added to ordinary differential equations and represent time needed for transformation from one type of cells to the other one, affects the behavior of the system. The validation and verification of proposed model is based on medical data. Analytical results are illustrated by numerical examples of the model dynamics. The model is able to reconstruct dynamics of treatment of cancer and may be used to determine the most effective treatment regimen based on the study of the behavior of individual treatment protocols.

Keywords: mathematical modeling, numerical simulation, ordinary differential equations, radiation therapy

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Authors: Gulsen Yilmaz

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Istanbul’s population has jumped by over 1 million in the past four years, to a level surpassing the overall population of 64 provinces in the country, according to data from the Turkish Statistical Institute (TÜİK). In this paper, Istanbul's population change and migration effects can be examined in detail Tarlabasi neighborhood cultural center of the city of Istanbul, Istiklal Street, which is located a few hundred meters away. Tarlabasi the end of the nineteenth century in the historic district with built in the early twentieth century, there are four or five storey historic buildings. Tarlabasi, here come from southeastern Turkey and the illegal African immigrants living in Roma origin by the Kurds as a residential area is used. In this area to improve the quality of life for urban renewal projects have been initiated. The aim of this paper is to explore the spatial effects of demographic change and migration with Tarlabasi example.

Keywords: migration, immigration, Tarlabaşı, urban transformation

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Authors: Vedat Senol, Gursoy Turan, Anders Helmersson, Vortechz Andersson

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In developing a mathematical model of a real structure, the simulation results of the model may not match the real structural response. This is a general problem that arises during dynamic motion of the structure, which may be modeled by means of parameter variations in the stiffness, damping, and mass matrices. These changes in parameters need to be estimated, and the mathematical model is updated to obtain higher control performances and robustness. In this study, a linear fractional transformation (LFT) is utilized for uncertainty modeling. Further, a general approach to the design of an H∞ control of a magneto-rheological damper (MRD) for vibration reduction in a building with mass, damping, and stiffness uncertainties is presented.

Keywords: uncertainty modeling, structural control, MR Damper, H∞, robust control

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Authors: Fu Jiayan, Wang Zhu, Sun Jiaojiao

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Mixed-use development is one of the most important trends in new island house transformation along southeast coastal area in China. Unique island geographical environment and profound fishing village culture coexist for a long time in this. With artistic creation for the purpose of the "live-work" houses are in a large number of emergence, however, still lack of systematic strategy. Based on space effect from marine resources to regional human settlements, this article teases out the evolution regularity of island settlement context and architectural form, then, puts forward the formation mechanism and construction model of art island houses. Thereby, to further explore space design method and site creation strategy of mixed-use development.

Keywords: mixed-use, island house, art creation, Southeast Coastal Area of Chinese

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Authors: Ahmad Awajan, Sadam Al Wadi

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In this study, a hybrid method based on Empirical Mode Decomposition and Holt-Winter (EMD-HW) is used to forecast Amman stock market data. First, the data are decomposed by EMD method into Intrinsic Mode Functions (IMFs) and residual components. Then, all components are forecasted by HW technique. Finally, forecasting values are aggregated together to get the forecasting value of stock market data. Empirical results showed that the EMD- HW outperform individual forecasting models. The strength of this EMD-HW lies in its ability to forecast non-stationary and non- linear time series without a need to use any transformation method. Moreover, EMD-HW has a relatively high accuracy comparing with eight existing forecasting methods based on the five forecast error measures.

Keywords: Holt-Winter method, empirical mode decomposition, forecasting, time series

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Authors: Fiona Lord

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This paper presents research on strengthening urban governance and planning practices for sustainable and regenerative city transformations looking at urban governance in Cambodia as a case study. Transformations to urban sustainability and regeneration require systemic and long-term transformation processes, across multiple levels of society and inclusive of multiple urban actors. This paper presents the emerging findings of a qualitative case study comparing the urban governance and planning practices in two of Cambodia's secondary cities - Battambang and Sihanoukville. The lessons learned have broader implications for how governance and planning can be strengthened to initiate and sustain urban sustainability transformations in other developing country cities of Cambodia and the Southeast Asia region.

Keywords: Cambodia, planning practices, urban governance, urban sustainability transformations

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Authors: Alaa Eldien Sarhaan, Rania A. Galil, Yasmina Youssef

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Vital streets transfer a totally different message from the lifeless streets; vitality is considered as the mobility dynamism for the city’s streets. The quality of a street is integral to the vitality. However, most efforts have focused on the requirements of cars resulting in the loss many qualities. A successful street is related to the needs and expectations of pedestrians. The amount of activity held in a place is one of the measures of vitality; hence the meaning of a vital street may be the result of a number of people engaged in various activities meeting their needs and expectations. Consequently, it varies from one city to another. This research focuses on vitality in commercial streets. It studies commercial streets in the Egyptian context, which have developed into a chaotic environment due to inefficiency and high-density activities. The first part identifies the meaning of vitality in the frame of its physical, social and economic dimensions, then determines the methods used in measuring vitality across commercial streets. Secondly, an application on one of the most important commercial streets in Alexandria ‘El-Attareen’ street is chosen as a case study to measure its vitality. The study contributes to a greater understanding of how theories on vital urban life contribute to the development of vital commercial streets in the Egyptian and similar contexts.

Keywords: footfall measurement, vitality, urban commercial streets, yield factor

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Authors: David Kramsky, Barbora Vegrichtova

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The prison facility is generally considered as an environment having a corrective purpose. Besides the social sense of remedy, prison is also an environment that potentially determines and affects socially dangerous behavior. The authors, based on long-term empirical research, present the significant indicators that are directly related to the transformation of personality attitudes, motivations and behavior associating with a process of radicalization. One of the most significant symptoms of radicalization is a particular social moral decision making. Individuals in the radicalism process primarily prefer utilitarian manners of decision-making more than personal aspects like empathy for others. The authors will present the method of social moral profiling of the subject in radicalization process as an effective prevention system reducing security risks in society.

Keywords: indicators, moral decision, radicalism, social profile

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Authors: Adelayo Akeem Jolaoye

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Historically urban centers serve as the fulcrum upon which significant complex social and economic development rest. Despite their fixed geographical locations, though in different degree, cities generate self-sustenance and multiplier effects in all aspects of life. They also house inestimable human capital, which serves as a power house for future generation transformation requirements. Unfortunately, the untamed global urbanization process has resulted in an unimaginable damage to the urban social structure as well as urban environmental value. The preceding has caused cities failure in performing their expected roles worst still becoming a regional burden and national liabilities. This paper briefly discusses the ecological concept of urban settlements and reviews the world historical urban evolution and growth. Also, given the above-mentioned anomalies, the paper also raised conceptual principles of urban planning as well as administrative policies for its strategic management.

Keywords: city, urbanization, urban planning, urban malice

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Authors: Rajesh Kondareddy, Prakash Kumar Nayak, Maunash Das, Vrinatri Velentina Boro

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Today, there is a huge global concern for sustainable development which would include minimizing the consumption of non-renewable energies without affecting the basic global economy. Solar drying is one of the important processes used for extending the shelf life of agricultural products. The performance of a low cost automated solar dryer fitted with cascade control scheme and modified PI controller for drying chilli was investigated. The dryer was composed of designed solar collector (air heater) fitted with cylindrical pipes to improve the air velocity and a solar drying chamber containing rack of two cheese cloth (net) trays both being integrated together. The air allowed in through air inlet is heated up in the solar collector and channelled through the drying chamber where it is utilized in drying (removing the moisture content from the food substance or agricultural produce loaded). Here, to maintain the temperature in the heating chambers and to improve performance, a modified PI (Proportional–Integral) controller was used due its simplicity and robustness. Drying time for drying chilli from the initial moisture content of 88.5% (wb) to 7.3% (wb) was estimated to be 14 hours in solar dryer whereas 32 h was observed in the open sun drying.

Keywords: cascade control, chilli, PI controller, solar dryer

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Authors: Pataramon Satalak, Sakrit Isariyanon, Teerapong Puripanik

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This article uses the recent events in Thailand as a case study for examining why democratic transition is necessary during political upheaval to ensure that the people’s power remains unaffected. After seizing power in May 2014, the military, backed by anti-government protestors, selected and established their own system to govern the country. They set up the National Council for Peace and Order (NCPO) which established a People’s Assembly, aiming to reach a compromise between the conflicting opinions of former, pro-government and anti-government protesters. It plans to achieve this through political reform before returning sovereign power to the people via an election in 2018. If a governmental authority is not representative of the people (e.g. a military government) it does not count as a legitimate government. During the last four years of military government, from May 2014 to January 2018, their rule of Thailand has been widely controversial, specifically regarding their commitment to democracy, human rights violations and their manipulation of the rule of law. Democratic legitimacy relies not only on established mechanisms for public participation (like referendums or elections) but also public participation based on accessible and educational reform (often via NGOs) to ensure that the free and fair will of the people can be expressed. Through their actions over the last three years, the Thai military government has damaged both of these components, impacting future public participation in politics. The authors make some observations about the specific actions the military government has taken to erode the democratic legitimacy of future public participation: the increasing dominance of military courts over civil courts; civil society’s limited involvement in political activities; the drafting of a new constitution and their attempt to master support through referenda and its consequence for delaying organic law-making process; the structure of the legislative powers (Senate and the members of parliament); and the control of people’s basic freedoms of expression, movement and assembly in political activities. One clear consequence of the military government’s specific actions over the last three years is the increased uncertainty amongst Thai people that their fundamental freedoms and political rights will be respected in the future. This will directly affect their participation in future democratic processes. The military government’s actions (e.g. their response to the UN representatives) will also have influenced potential international engagement in Thai civil society to help educate disadvantaged people about their rights, and their participation in the political arena. These actions challenge the democratic idea that there should be a checking and balancing of power between people and government. These examples provide evidence that a democratic transition is crucial during any process of political transformation.

Keywords: political tranformation, public participation, Thailand coup d'etat 2014, election 2018

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Authors: Tomáš Dyk, Stanislav Procházka, Martin Drahanský

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The article proposes a new algorithm for detecting damaged areas of the tank barrel based on the image of the inner surface of the tank barrel. Damage position is calculated using image processing techniques such as edge detection, discrete wavelet transformation and image segmentation for accurate contour detection. The algorithm can detect surface damage in smoothbore and even in rifled tank barrels. The algorithm also calculates the volume of the detected damage from the depth map generated, for example, from the distance measurement unit. The proposed method was tested on data obtained by a tank barrel scanning device, which generates both surface image data and depth map. The article also discusses tank barrel scanning devices and how damaged surface impacts material resistance.

Keywords: barrel, barrel diagnostic, image processing, surface damage detection, tank

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Authors: Peter Schnell, Phillip Haag

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In the course of the structural transformation of the construction industry, the integration of industrialization and digitization has led to the development of construction methods with an increased degree of prefabrication, such as system or modular construction. Compared to conventional construction, these innovative construction methods are characterized by modified structural and procedural properties and expand the range of construction services. Faced with the supply side, it is possible to identify construction-specific customer types with different characteristics and certain preferences as far as the choice of construction method is concerned. The basis for this finding was qualitative expert interviews. By evaluating the stereotypical customer needs, a corresponding segmentation of the demand side can be made along with the basic orientation and decision behavior. This demarcation supports the target- and needs-oriented customer approach and contributes to cooperative and successful project management.

Keywords: differentiation of customer types, modular construction methods, conventional construction methods, stereotypical customer types

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Authors: Piyush Samant, Ravinder Agarwal

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Complementary and Alternative Medicine (CAM) techniques are quite popular and effective for chronic diseases. Iridology is more than 150 years old CAM technique which analyzes the patterns, tissue weakness, color, shape, structure, etc. for disease diagnosis. The objective of this paper is to validate the use of iridology for the diagnosis of the diabetes. The suggested model was applied in a systemic disease with ocular effects. 200 subject data of 100 each diabetic and non-diabetic were evaluated. Complete procedure was kept very simple and free from the involvement of any iridologist. From the normalized iris, the region of interest was cropped. All 63 features were extracted using statistical, texture analysis, and two-dimensional discrete wavelet transformation. A comparison of accuracies of six different classifiers has been presented. The result shows 89.66% accuracy by the random forest classifier.

Keywords: complementary and alternative medicine, classification, iridology, iris, feature extraction, disease prediction

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Authors: J. Areerut

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Experimental Film Class Project is supported by the Institute for Research and Development at Suan Sunandha Rajabhat University. This project is purported to provide academic and professional services to improve the quality standards of the community and locals in accordance with the mission of the university, which is to improve and expand knowledge for the community and to develop and transfer such knowledge and professions to the next generation. Eventually, it leads to sustainable development because the development of human resources is deemed as the key for sustainable development. Moreover, the Experimental Film Class is an integral part of the teaching of film production at Suan Sunandha International School of Art (SISA). By means of giving opportunities to students for participation in projects by sharing experience, skill and knowledge and participation in field activities, it helps students in the film production major to enhance their abilities and potentials as preparation for their readiness in the marketplace. Additionally, in this class, we provide basic film knowledge, screenwriting techniques, editing and subtitles including uploading videos on social media such as YouTube and Facebook for the participant students.

Keywords: experimental film class, Watbangkapom School, participant students, basic of film production, film workshop

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Authors: Jam Harley

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The COVID-19 epidemic accelerated the speed of change in the workplace. Overnight, several individuals shifted from co-location in an office to hybrid or remote work. The pandemic also expedited and intensified the need to address persistent leadership and management concerns, including digital transformation, remote management, leading through fast change, anxiety, and uncertainty. Nonetheless, many leaders have failed to address the problems left behind by the epidemic. In a fundamental work devoted to comprehending what constitutes a human need, Maslow reiterates similar descriptors in his explanation of belongingness as the human need to be accepted, acknowledged, respected, and appreciated by a community of other individuals. This study aims to investigate the lived experiences of dispersed hybrid team members in order to find leadership best practices that improve team performance and retention through an increased individual’s sense of belonging.

Keywords: organizational change, belonging, diversity, equity

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Authors: Wael I. Alnahhal

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It is a major challenge to build a bridge superstructure that has long-term durability and low maintenance requirements. A solution to this challenge may be to use new materials or to implement new structural systems. Fiber reinforced polymer (FRP) composites have continued to play an important role in solving some of persistent problems in infrastructure applications because of its high specific strength, light weight, and durability. In this study, the concept of the hybrid FRP-concrete structural systems is applied to a bridge superstructure. The hybrid FRP-concrete bridge superstructure is intended to have durable, structurally sound, and cost effective hybrid system that will take full advantage of the inherent properties of both FRP materials and concrete. In this study, two hybrid FRP-concrete bridge systems were investigated. The first system consists of trapezoidal cell units forming a bridge superstructure. The second one is formed by arch cells. The two systems rely on using cellular components to form the core of the bridge superstructure, and an outer shell to warp around those cells to form the integral unit of the bridge. Both systems were investigated analytically by using finite element (FE) analysis. From the rigorous FE studies, it was concluded that first system is more efficient than the second.

Keywords: bridge superstructure, hybrid system, fiber reinforced polymer, finite element analysis

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Authors: Ritu Ahuja

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Globally the built environment sector is striving to be highly efficient, quality-centred and socially-responsible. Built environment sector is an integral part of the economy and plays an important role in urbanization, industrialization and improved quality of living. The inherent challenges such as excessive material and process waste, over reliance on resources, energy usage, and carbon footprint need to be addressed in order to meet the needs of the economy. It is envisioned that these challenges can be resolved by integration of Lean-Green-Building Information Modelling (BIM) paradigms. Ipso facto, with BIM as a catalyst, this research identifies the operational and tactical connections of lean and green philosophies by providing a conceptual integration framework and underpinning theories. The research has developed a framework for BIM-based organizational capabilities for enhanced adoption and effective use of BIM within architectural organizations. The study was conducted through a sequential mixed method approach focusing on collecting and analyzing both qualitative and quantitative data. The framework developed as part of this study will enable architectural organizations to successfully embrace BIM on projects and gain lean and green benefits.

Keywords: BIM, lean, green, AEC organizations

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Authors: Pooja Pandey

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The role of communication plays an integral part in the management of any disaster, whether natural or human-induced, both require effective and strategic delivery of information. The way any information is conveyed carries the most weight while dealing with the disaster. Hence, integrating communication strategies in disaster risk management (DRM) are extensively acknowledged however, these integration and planning are missing from the practical books. Researchers are continuously exploring integrated DRM and have established substantial vents between research and implementation of the strategies (gaps between science and policy). For this reason, this paper reviews the communication barriers that obstruct effective management of the disaster. Communication between first responders (government agencies, police, medical services) and the public (people directly affected by the disaster) is most critical and lacks proper delivery during a disaster. And these challenges can only be resolved if the foundation of the problem is properly dealt with, which is resolving the issues within the organizations. Through this study, it was found that it is necessary to build the communication gap between the organizations themselves as most of the hindrances occur during the mitigation, preparedness, response and recovery phase of the disaster. The study is concluded with the main aim to review the communication barriers within and at the organizational, technological, and social levels that impact effective DRM. In the end, some suggestions are made to strengthen the knowledge for future improvement in communication between the responders and their organizations.

Keywords: communication, organization, barriers, first responders, disaster risk management

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Authors: Lusine S. Stepanyan, Elina V. Asriyan.

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It is known, that the efficiency of management depend on individual characteristics of manager. In case, was shown the role of personal position in the efficiency of management. Current research is aimed at reveal psychological and psychophysiological basis efficiency of management and finding ways of increasing the productivity of management that is most essential and topical problems of modern society. To understand the investigated phenomenon it was applied a complex approach. The Eysenk questionnaire was used for determining the level of aggression, frustration, anxiety and rigidity. The test of egocentric associations was used for determining the level of egocentrism. The test of COS (communicativeness and organizational skills) was used for diagnosing the level of communicativeness. The integral index of job satisfaction was used for diagnosis the efficiency of management activity. Then, the relationship between the above mentioned mental state, communicativeness, self-esteem, job satisfaction, locus of control, and egocentrism was investigated. The obtained results have shown the positive correlation between the egocentrism and frustration, anxiety and also the negative correlation with job satisfaction and communicativeness. Intergroup analyses has revealed the significant differences by communicativeness and the internality’ level. The revealed results can be used for diagnosis of efficiency of management.

Keywords: egocentrism, locus control, mental state, job satisfaction, professional activity

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Authors: D. Subedi, S. Pradhan

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Current transformers are an integral part of power system because it provides a proportional safe amount of current for protection and measurement applications. However when the power system experiences an abnormal situation leading to huge current flow, then this huge current is proportionally injected to the protection and metering circuit. Since the protection and metering equipment’s are designed to withstand only certain amount of current with respect to time, these high currents pose a risk to man and equipment. Therefore during such instances, the CT saturation characteristics have a huge influence on the safety of both man and equipment and also on the reliability of the protection and metering system. This paper shows the effect of burden on the Accuracy Limiting factor/ Instrument security factor of current transformers and also the change in saturation characteristics of the CT’s. The response of the CT to varying levels of overcurrent at different connected burden will be captured using the data acquisition software LabVIEW. Analysis is done on the real time data gathered using LabVIEW. Variation of current transformer saturation characteristics with changes in burden will be discussed.

Keywords: accuracy limiting factor, burden, current transformer, instrument security factor, saturation characteristics

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Authors: N. W. Paul, M. Banerjee

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Discussing the nexus between global health policy and local practices, this article addresses the recent Ebola outbreak as a role model for narrative co-constructions of epidemic risk. We will demonstrate in how far a theory-driven and methodologically rooted analysis of narrativity can help to improve mechanisms of prevention and intervention whenever epidemic risk needs to be addressed locally in order to contribute to global health. Analyzing the narrative transformation of Ebola, we will also address issues of transcultural problem-solving and of normative questions at stake. In this regard, we seek to contribute to a better understanding of a key question of global health and justice as well as to the underlying ethical questions. By highlighting and analyzing the functions of narratives, this paper provides a translational approach to refine our practices by which we address epidemic risk, be it on the national, the transnational or the global scale.

Keywords: ebola, epidemic risk, medical ethics, medical humanities

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Authors: Shield B. Lin, Ziraguen O. Williams

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In a task to assist NASA in analyzing the dynamic forces caused by operational countermeasures of an astronaut’s exercise platform impacting the spacecraft, an active proportional-integral-derivative controller commanding a linear actuator is proposed in a vibration isolation system to regulate the movement of the exercise platform. Computer simulation shows promising results that most exciter forces can be reduced or even eliminated. This paper emphasizes on parameter uncertainties, variations and exciter force variations. Drift and variations of system parameters in the vibration isolation system for astronaut’s exercise platform are analyzed. An active controlled scheme is applied with the goals to reduce the platform displacement and to minimize the force being transmitted to the spacecraft structure. The controller must be robust enough to accommodate the wide variations of system parameters and exciter forces. Computer simulation for the vibration isolation system was performed via MATLAB/Simulink and Trick. The simulation results demonstrate the achievement of force reduction with small platform displacement under wide ranges of variations in system parameters.

Keywords: control, counterweight, isolation, vibration

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Authors: Ould Bouamama, M. Bressel, D. Hissel, M. Hilairet

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Fuel cell (FC) is one of the best alternatives of fossil energy. Recently, the research community of fuel cell has shown a considerable interest for diagnosis in view to ensure safety, security, and availability when faults occur in the process. The problematic for model based FC diagnosis consists in that the model is complex because of coupling of several kind of energies and the numerical values of parameters are not always known or are uncertain. The present paper deals with use of one tool: the Linear Fractional Transformation bond graph tool not only for uncertain modelling but also for monitorability (ability to detect and isolate faults) analysis and formal generation of robust fault indicators with respect to parameter uncertainties.The developed theory applied to a nonlinear FC system has proved its efficiency.

Keywords: bond graph, fuel cell, fault detection and isolation (FDI), robust diagnosis, structural analysis

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Authors: Lakhya Jyoti Basumatary, M. J. Davidson

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Tailor Welded Blanks (TWBs) have established themselves to be a revolutionary and foremost integral part of the automotive and aerospace industries. Metals sheets with varied thickness, strength and coatings are welded together to form TWBs through friction stir welding and laser welding prior to stamping operations. The formability of the TWBs completely varies from those of conventional blanks due to the diverse strength levels of individual sheets which are made to deform under the same forming load uniformly throughout causing unequal and unsatisfactory deformation in the blank. Limiting Dome Height(LDH) test helps predicting the formability of each blanks and assists in determining the appropriate TWB. Finite Element Simulation of LDH test for both base material and TWBs was performed and analysed for both before and after the solution heat treatment. The comparison and validation of simulation results are done with the experimental data and correlated accordingly. The formability of solution heat treated TWBs had enhanced than those of blanks made from non-heat treated TWBs.

Keywords: tailor welded blanks, friction stir welding, limiting dome height test, finite element simulation

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Authors: Fayssal Amrane, Azeddine Chaiba, Bruno Francois

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In this paper, design and experimental study based on Direct Power Control (DPC) of DFIG is proposed for Stand-alone mode in Variable Speed Wind Energy Conversion System (VS-WECS). The proposed IDPC method based on robust IP (Integral-Proportional) controllers in order to control the Rotor Side Converter (RSC) by the means of the rotor current d-q axes components (Ird* and Irq*) of Doubly Fed Induction Generator (DFIG) through AC-DC-AC converter. The implementation is realized using dSPACE dS1103 card under Sub and Super-synchronous operations (means < and > of the synchronous speed “1500 rpm”). Finally, experimental results demonstrate that the proposed control using IP provides improved dynamic responses, and decoupled control of the wind turbine has driven DFIG with high performances (good reference tracking, short response time and low power error) despite for sudden variation of wind speed and rotor references currents.

Keywords: Direct Power Control (DPC), Doubly fed induction generator (DFIG), Wind Energy Conversion System (WECS), Experimental study.

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Authors: Ha T. Pham, Shuichi Miyagawa

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Ongoing landscape transformation is one of the major causes behind disappearance of traditional landscapes, and lead to species and resource loss. Tree in paddy fields in the northeast of Thailand is one of those traditional landscapes. Using three different historical time layers, we acknowledged the severe deforestation and rapid urbanization happened in the region. Despite the general thinking of decline in tree density as consequences, the heterogeneous trend of changes in total tree density in three studied landscapes denied the hypothesis that number of trees in paddy field depend on the length of land use practice. On the other hand, due to selection of planting new trees on levees, existence of trees in paddy field are now rely on their values for human use. Besides, changes in land use and landscape structure had a significant impact on decision of which tree density level is considered as suitable for the landscape.

Keywords: aerial photographs, land use change, traditional landscape, tree in paddy fields

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Authors: Luiz Antonio Da Costa Rodrigues, Mara Aparecida De Castilho Lopes, Alexandre Santos Alencar

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Teaching of science must transcend simple transmission of fundamental concepts and allow scientific literacy, as a process for understanding the human being as an integral part of a complex and interdependent whole. In this context, approaching the theme ‘Antarctica’ in deaf education is an important advance for teaching, considering that that continent has direct interactions with the climatic and environmental system of the planet. Therefore, textbooks can be important tools to enable the Deaf Community to access the discussion about the natural environment. A specific script was used to analyze textbooks adopted by schools in the Rio de Janeiro Metropolitan Region. Results show that none of the 14 analyzed books have a specific chapter on the theme, some presents images of the continent without reference to their environmental importance, and the complementary texts present in the analyzed material do not address the theme either. It is concluded that the study on Antarctica and global changes in elementary education is still incipient and the material used by most Brazilian public schools does not contemplate that subject in an accessible way for the deaf person. This fact represents the distance between deaf students and their environment, denoting the need for actions to promote that and other neglected themes in Science teaching.

Keywords: Antarctica, deaf education, science teaching, textbook

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Authors: Ramin Khamedi, Isa Ahmadi

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In this study acoustic emission (AE) signals obtained during deformation and fracture of two types of ferrite-martensite dual phase steels (DPS) specimens have been analyzed in frequency domain. For this reason two low carbon steels with various amounts of carbon were chosen, and intercritically heat treated. In the introduced method, identifying the mechanisms of failure in the various phases of DPS is done. For this aim, AE monitoring has been used during tensile test of several DPS with various volume fraction of the martensite (VM) and attempted to relate the AE signals and failure mechanisms in these steels. Different signals, which referred to 2-3 micro-mechanisms of failure due to amount of carbon and also VM have been seen. By Fast Fourier Transformation (FFT) of signals in distinct locations, an excellent relationship between peak frequencies in these areas and micro-mechanisms of failure were seen. The results were verified by microscopic observations (SEM).

Keywords: acoustic emission, dual phase steels, deformation, failure, fracture

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Authors: Manwendra Kumar Tripathi, Subhas Ganguly

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A few glass forming ability expressions in terms of characteristic temperatures have been proposed in the literature. Attempts have been made to correlate the expression with the critical diameter of the bulk metallic glass composition. However, with the advent of new alloys, many exceptions have been noted and reported. In the present approach, a genetic programming based code which generates an expression in terms of input variables, i.e., three characteristic temperatures viz. glass transition temperature (Tg), onset crystallization temperature (Tx) and offset temperature of melting (Tl) with maximum correlation with a critical diameter (Dmax). The expression evolved shows improved correlation with the critical diameter. In addition, the expression can be explained on the basis of time-temperature transformation curve.

Keywords: glass forming ability, genetic programming, bulk metallic glass, critical diameter

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