bluuebunny/crossref_metadata_2025 huggingface dataset:
El estadio cubierto de Dartmouth, Estados Unidos
Authors: Nervi Pier Luigi
Published: August 2015

Este estadio ha sido construido en Hanovre (U.S.A.) para la Universidad de Dartmouth.
Está cubierto con una bóveda alveolada de 110 m de longitud y 69,80 m de luz, con altura libre máxima de 18,30 m y apoyada en soportes de hormigón armado, espaciados a 5,70 metros.
Cada soporte está constituido por tres elementos formando triángulo rectángulo: cuya hipotenusa es el elemento transmisor de esfuerzos al estribo; el montante, el apoyo de arranques, y el elemento horizontal, la pieza de arriostramiento.
La estructura está formada por elementos triangulares, prefabricados, unidos por medio de nervios cruzados realizados en obra, que se empotran, en sus extremos, a dos vigas continuas. La construcción se ha llevado a cabo por tramos sucesivos, de 8,50 metros.
Bases de un método racional para el dimensionamiento de refuerzos de firmes flexibles, basado en la medida de la deformación puntual bajo un eje cargado, I parte
Authors: Rocci Sandro
Published: August 2015

Este artículo constituye una descripción cualitativa de los factores que intervienen en el comportamiento del firme de una carretera, y de las relaciones entre ellos, estableciéndose un esquema funcional cuyo objetivo último económico es la minimización del coste total (construcción + conservación + explotación) de una carretera. Al mismo tiempo, se establecen las bases para un método de dimensionamiento de refuerzo de firmes flexibles, cuya justificación cuantitativa será objeto de un próximo artículo.
Edificio Rosental, en Basilea, Suiza
Authors: Suter & Suter Arquitectos
Published: August 2015

El nuevo edificio para exposiciones construido en el recinto de la Feria de Muestras de Basilea, consta de: dos sótanos, planta baja, entreplanta y dos plantas de altura.
El segundo sótano contiene los almacenes; el primer sótano está destinado a exposición de mercancías; la planta baja, a exhibición de mercancías y maquinaria pesada; la entreplanta, a exposiciones especiales; y las otras dos plantas, a exposiciones normales.
La construcción ha sido realizada a base de elementos prefabricados de hormigón armado.
Edificio de oficinas, en Madrid
Authors: Barbero Rebolledo M. , Ortiz-Echagüe C. , Echaide Itarte R. , Joya Castro R.
Published: August 2015

Este edificio para oficinas fue proyectado según un módulo de 1,60 x 1,60 m, de tal manera que admitiese la máxima flexibilidad en su distribución y se adaptase a todos los cambios de organización que pudieran presentarse en el futuro. La estructura es metálica; los cerramientos, de ladrillo visto y cristal, según conviene a cada zona; y en su composición y tratamientos exterior e interior se han aunado sabiamente los dos principios básicos de representatividad y confort exigidos.
Además de alojar las oficinas centrales de la Sociedad Española de Automóviles de Turismo en Madrid, como elementos singulares dispone de: salón de actos, exposición de automóviles y servicio de ordenador electrónico.
Bases de un método racional para el dimensionamiento de refuerzos de firmes flexibles, basado en la medida de la deformación puntual de un eje cargado. II parte
Authors: Rocci Sandro
Published: August 2015

Este artículo constituye una descripción cualitativa de los factores que intervienen en el comportamiento del firme de una carretera, y de las relaciones entre ellos, estableciéndose un esquema funcional cuyo objetivo último económico es la minimización del coste total (construcción + conservación + explotación) de una carretera. Al mismo tiempo, se establecen las bases para un método de dimensionamiento de refuerzo de firmes flexibles, cuya justificación cuantitativa será objeto de un próximo artículo.
Consideraciones sobre las máquinas de neumáticos y cadenas (Parte I)
Authors: Chinchilla M.
Published: August 2015

La evolución de la maquinaria se realiza normalmente de una forma continuada y progresiva. De vez en cuando aparecen, sin embargo, posibilidades nuevas que abren campos diferentes y que requieren técnicas distintas, tanto en el empleo como en la construcción y diseño de estos tipos de maquinaria. Uno de estos casos concretos, lo ha sido la aparición de las ruedas neumáticas en las máquinas topadoras, como consecuencia de su empleo en las unidades cargadoras. Los cambios sufridos en estos últimos diez años han sido tan grandes, que puede decirse que hasta hace muy poco el empleo de los neumáticos en las máquinas topadoras y cargadoras no ha quedado bien delimitado en cuanto a sus requerimientos y sus posibilidades. De todas formas, ya pueden enunciarse las principales características que diferencian las máquinas de cadenas y neumáticos, de la misma clase; una de estas características es la particularización que requieren las máquinas de neumáticos en su empleo y en las condiciones de trabajo, a diferencia de las máquinas de orugas, las cuales permiten realizar trabajos de carga o empuje en condiciones variadas.
«Ente siciliano di elettricità», Catania
Authors: Battaglini M. , De Sanctis S. , Tenca F. , Spampinato G. , Benedetti C.
Published: August 2015

El edificio, objeto de este artículo, consta de: sótano, planta baja, siete plantas destinadas a oficinas, y un octavo piso, que contiene el bar y un amplio salón de descanso para uso de los empleados; la zona más alta de la cubierta puede ser utilizada como eventual estación de helicópteros.
La organización volumétrica del conjunto edificado—con vistas a conseguir una mayor impresión de amplitud en la plaza—y la disposición peculiar de vigas y pilares de la planta baja confieren a esta obra un carácter destacado y singular.
Nuevo hospital provincial, en Riedlingen, Alemania
Authors: Krahn Johannes
Published: August 2015

Este edificio está constituido por cinco bloques comunicados entre sí:
Cuerpo A, de 8 plantas, contiene: el ingreso para los accidentados, las dependencias de la administración, unidades de tratamiento, farmacia, laboratorio, archivo, etc.; el B, de 3 plantas, aloja: la sala de ginecología, cocinas, frigoríficos, instalaciones de calefacción, etc.; el C, de 3 plantas, alberga: los quirófanos, locales anexos, etc.; en el D, de 2 plantas, se encuentran : la lavandería, el comedor, etc.; el resto del antiguo hospital, cuerpo F, de 3 plantas, está destinado a pabellón para alojar los internados que necesitan aislamiento; y en el E está la capilla.
El conjunto se ha construido a base de hormigón visto y zonas de «Ytong», disponiendo de las más modernas instalaciones.
Informe sobre la Conferencia Internacional de Bad Meinberg
Authors: Llamazares Gómez Olegario
Published: August 2015

Expone el autor las características, especificaciones y procesos de ejecución de dos unidades de obra muy importantes en carreteras: el pedraplén y las capas de base del firme, refiriéndose concretamente a las bases de hormigón pobre recomendadas para vías de tráfico pesado.
La ejecución de pedraplenes, hasta ahora de difícil normalización y control, constituye un problema de la técnica vial por el temor a asientos diferenciales bajo la repetición de las pesadas cargas del tráfico. En las normas de que se informa en el presente trabajo, deducidas del comportamiento de tramos experimentales ingleses, se fijan, con una precisión, en la que reside su novedad, los tamaños máximos de los materiales, graduación de éstos, espesores de las capas y sistema óptimo de compactación.
Las bases de hormigón pobre, con dosificaciones del orden del 6 por 100, en peso, dan una mayor rigidez a los firmes flexibles, por lo que pueden computarse su espesor por el doble que el de una base granular, lo que reduce la diferencia de ambas soluciones en el aspecto económico.
Determinantes del salario en Chile. Un análisis desde el paradigma de la reproducción social
Authors: Rodrigo Luis Miguel
Published: August 2015

Frente al paradigma económico neoclásico, hegemónico en la explicación del salario, se presenta el paradigma sociológico de la Reproducción Social, a partir de la obra de Pierre Bourdieu, para dar cuenta de la diferencia salarial en Chile. Después de exponer y comparar ambos paradigmas teóricos, se describe el caso de estudio, destacando las peculiaridades del modelo neoliberal chileno. Para comparar la capacidad explicativa de ambos enfoques, se estima el salario de los chilenos mediante la encuesta de Caracterización Socioeconómica Nacional 2009 (CASEN) a partir de dos modelos estadísticos, el modelo neoclásico basado en las ecuaciones de Mincer y un modelo que trata de capturar empíricamente los factores explicativos propios del paradigma de la Reproducción Social. Los resultados indican que, en el caso de Chile, el modelo Reproductivo tiene mayor capacidad explicativa que el Neoclásico, tanto para el conjunto de los asalariados, como para cada una de las generaciones que lo componen.
Emergent Behavior in Complex Organizations
Authors: Alvarez-Molina Ernesto R. , Martínez Luis G. , Castañón-Puga Manuel , Rodriguez-Diaz Antonio
Published: August 2015

Organizations are complex systems, which are formed by other subsystems such as work teams, and are the focus of attention in this research. This article makes an approach to the teams involved software development process in IT companies using a viable system based model and computational modeling. An analysis of teamwork is made from a socio-technical perspective, where individuals and technology produce emergent behaviors that may be crucial to achieving goals, since fellowship, collaboration, and culture are relevant processes within these organizations and technology also playing an important role.
An Overview on Access Control Models
Authors: Mammass Mouad , Ghadi Fattehallah
Published: August 2015

Research in the field of information security systems and access control were initiated in the early seventies by United States Department of Defense, following the emergence of new technical, scientific and social challenges. Since, many models of security have been set up to answer to some specific needs with more or less accuracy in term of security. This manuscript gives a survey on the current security models with a specific classification in term of their use: Access Control, Flow Control and Administration. This manuscript is the subject of an assessment of advantages and drawbacks of access control models cited in literature and also the efficiency of their security policies. Finally, a presentation of the contributions of Flow Control and Administration models that allow the reinforcement of the security.
Parametric Survival Modelling of Risk Factor of Tuberculosis Patients under DOTS Program at Hawassa Town, Ethiopia
Authors: Chere Fikadu Zawdie , Tesfay Yohannes Yebabe , Enquoselassie Fikre
Published: August 2015

Tuberculosis (TB) is a chronic infectious disease that has a major health problem over the centuries. This study assessed the risk factors associated with time to death among TB patients treated under directly observed short course treatment program in Health facilities in Hawassa city, Ethiopia. The authors analysed data from a cohort of 1604 TB patients recruited between September 2008 to September 2011. They apply the parametric regression model of survival data analysis. The best fitted parametric regression model is selected by using the Akaike information criterion (AIC). The AIC confirms that the Weibull regression model is found to be the best fit of the survival of tuberculosis patients under the DOTS program at Hawassa town, Ethiopia. The fit of the Weibull regression model result revealed that sex, age, baseline weight, HIV status, category of patients and year of enrolment are the significant factor for the survival of TB patients.
Effect of Wavelet Packet Log Energy Entropy on Electroencephalogram (EEG) Signals
Authors: Raghu S. , Sriraam N. , Kumar G. Pradeep
Published: August 2015

The scaling behavior of human electroencephalogram (EEG) signals is well exploited by appropriate extraction of time – frequency domain and entropy based features. Such measurable inherently helps understanding the neurophysiological phenomenon of brain as well as its associated cortical activities. Being a non-linear time series, EEG's are assumed to be fragment of fluctuations. Several attempts have been made to study the EEG signals for clinical applications such as epileptic seizure detection, evoked response potential recognition, tumor detection, identification of alcoholics and so on. In all such applications appropriate selection of feature parameter plays an important role in discriminating normal EEG from abnormal. In the recent past one can find the importance of wavelet and wavelet packet towards EEG analysis. This proposed research work investigates the effect of wavelet packet log energy entropy on EEG signals. Entropy being the measure of relative information, the proposed study attempts to discriminate the normal EEGs from abnormal EEG's by employing the log energy entropy features. For better brevity, this study restricts to the analysis of epileptic seizure from normal EEGs. Different decomposition levels from 2 to 5 were considered for wavelet packets with application of Haar, rbio3.1, sym7, dmey wavelets. A one second windowing was introduced for the data segmentation and Shannon's log energy entropy was estimated. Then the statistical non-parametric Wilcoxon model was employed. The result shows that the application of wavelet packet log energy entropy found to be a potential indicator for discriminating epileptic seizure from normal.
Co-Creating Games with Children
Authors: Mouws Karen , Bleumers Lizzy
Published: August 2015

In this paper, the authors investigate the role of and relationship between creative production practices (e.g. problem-solving and self-evaluation) and cooperative learning mechanisms (e.g. building trust and group processing) in a case of game co-design. 21 Belgian school children created game concepts together with a game designer, their teacher, and co-design facilitators. During a project week at school, participants moved from idea generation to presenting game concepts through collaboratively created prototypes. This case study, combining observation and survey methods, reveals that self-evaluation and openness to sharing ideas emerged spontaneously, but the critical analysis of digital games and crediting existing work require support. Moreover, as creative choices become part of group deliberation, progress in the creative production process critically depends on group functioning. The authors conclude that by grounding co-design in theory on cooperative learning and media literacy, co-design activities may be better understood and new avenues for supporting co-creators can be identified.
The Differences between Problem-Based and Drill and Practice Games on Motivations to Learn
Authors: Deen Menno , van den Beemt Antoine , Schouten Ben
Published: August 2015

Two trends can be witnessed in educational game design: Problem-Based Learning and Drill & Practice Training approach. The general assumption appears to favor Problem-Based approach above Drill & Practice, in regard to players' motivation. However, the differences between the approaches are seldom studied. The authors examined the motivational impact of one game consisting of a Problem-Based-, and a Drill & Practice learning mode. The first presents players with an ill-defined problem and offers various solutions to a challenge. In the Drill & Practice mode, there is only one correct answer. Secondary school students played the game and completed a pre- and post-test questionnaire about their experienced regulatory style for studying mathematics. Results suggest that the Problem-Based mode may decline the experience of feeling controlled by others to engage in mathematics learning. In comparison, players of the Drill & Practice mode reported increased intrinsic motivations towards mathematics.
Lessons Learned and Best Practices of Stealth Assessment
Authors: Wang Lubin , Shute Valerie , Moore Gregory R.
Published: August 2015

Stealth assessment provides an innovative way to assess and ultimately support knowledge, skills, and other personal attributes within learning and gaming environments without disrupting students' flow. In this paper, the authors briefly discuss two challenges they encountered during the development of stealth assessments in two past projects (i.e., utility issues related to log files and validation issues related to in-game measures). They also present successful examples of designing and testing stealth assessments and describe the steps they are taking to apply the lessons they have learned to the ongoing development of a stealth assessment for problem solving skills. The authors conclude with suggestions for future research.
Users' Perception of Security for Mobile Communication Technology
Authors: Halaweh Mohanad
Published: August 2015

Security perception has been investigated by much research within the e-commerce and e-banking context. However, very little research has investigated this issue within the general mobile context without limiting this to particular applications such as payment, marketing, banking and commerce. Therefore, this paper aims to explore the users' perception of security towards mobile phones from a wide perspective. An interpretive-qualitative research was adopted to investigate the users' perceptions. The research results provided evidence for extending the meaning of the security perception concept to include human security as a relevant issue to mobile phone usage. It also showed that mobile phones can be used as an instrument to commit fraud and crimes. Furthermore, the results showed that the development of mobile technology raises new security and privacy concerns. For practical implications, this research provides recommendations for mobile technology designers to improve mobile usability- related issues in order to improve users' feeling of security
Balanced Approach for Hiding Sensitive Association Rules in Data Sharing Environment
Authors: Bonam Janakiramaiah , Reddy Ramamohan
Published: August 2015

Privacy preserving association rule mining protects the sensitive association rules specified by the owner of the data by sanitizing the original database so that the sensitive rules are hidden. In this paper, the authors study a problem of hiding sensitive association rules by carefully modifying the transactions in the database. The algorithm BHPSP calculates the impact factor of items in the sensitive association rules. Then it selects a rule which contains an item with minimum impact factor. The algorithm alters the transactions of the database to hide the sensitive association rule by reducing the loss of other non-sensitive association rules. The quality of a database can be well maintained by greedily selecting the alterations in the database with negligible side effects. The BHPSP algorithm is experimentally compared with a HCSRIL algorithm with respect to the performance measures misses cost and difference between original and sanitized databases. Experimental results are also mentioned demonstrating the effectiveness of the proposed approach.
Effective and Efficient Classification of Topically-Enriched Domain-Specific Text Snippets
Authors: Spruit Marco , Vlug Bas
Published: August 2015

Due to the explosive growth in the amount of text snippets over the past few years and their sparsity of text, organizations are unable to effectively and efficiently classify them, missing out on business opportunities. This paper presents TETSC: the Topically-Enriched Text Snippet Classification method. TETSC aims to solve the classification problem for text snippets in any domain. TETSC recognizes that there are different types of text snippets and, therefore, allows for stop word removal, named-entity recognition, and topical enrichment for the different types of text snippets. TETSC has been implemented in the production systems of a personal finance organization, which resulted in a classification error reduction of over 21%. Highlights: The authors create the TETSC method for classifying topically-enriched text snippets; the authors differentiate between different types of text snippets; the authors show a successful application of Named-Entity Recognition to text snippets; using multiple enrichment strategies appears to reduce effectivity.
Information Systems Security Policy Compliance
Authors: Nsoh Michael Warah , Hargiss Kathleen , Howard Caroline
Published: August 2015

The article describes research conducted to assess and address some key security issues surrounding the use of information technology from employee behavioral standpoint. The aim of the study was to determine additional security measures to reduce security incidents and maximize effective use of information systems. The research is an extension of several recent empirical studies in information systems security policy behavioral compliance, which have generally found people to be a weak link in information security. A mix of theoretical frameworks resulted in a model based on the Theory of Planned Behavior (TPB), which was used to test the impact that management and employee relationship has on deterrence. Results indicate that management has a significant stake in influencing the behavior of their employees, and that the issue of employee disgruntlement nevertheless is not paramount of top management's Information systems security challenges.
Comparison of Baccalaureate Nursing Students' Experience of Video-Assisted Debriefing versus Oral Debriefing following High-Fidelity Human Simulation
Authors: Royle Colleen , Hargiss Kathleen
Published: August 2015

High-Fidelity Human Simulation (HFHS) is used in many disciplines, including nursing, as an innovative teaching pedagogy that offers an active learning process. The simulation process involves a number of stages with the most critical stage identified as debriefing. The main focus of debriefing is to stimulate reflection and encourage communication while exploring the emotions of the participants. These emotions assist in framing the experience that aids in enhancement of learning for the student. This quantitative, quasi-experimental study explored the comparison of two debriefing processes, video-assisted and oral, by assessing the students' opinion of the debriefing experience and the students' rating of the importance of the debriefing experience. Participants were first semester baccalaureate nursing students. The overall finding and the four subscales for both dependent variables showed no statistical significance. This article provides further evidence to guide educators to a preferred method of debriefing students after a simulated experience.
ICT for Community Empowerment amongst Urban Underserved Communities
Authors: Lorini Maria Rosa
Published: August 2015

The paper highlights the methodological framework of an ongoing research focused on two issues of actuality in Information and Communication Technology for Development (ICT4D): the role of ICTs in cultivating collective capabilities and the role of the participants in the different phases of a new design project in relation to development. A design-based research approach, rooted in exploratory ethnography and emergent design shows that when the researcher becomes ethnographer and designer and the users become resources for the co-production, a new methodology is born. It is a process of dialogue, never ending, in which the designer enters with the intention to make an impact, not only to understand. The participatory process is followed throughout the research, from the ethnographic phase of discovery and understanding, through the design phase of co-creation, till the evaluation final phase. This research is conducted in two marginalised urban settings of Cape Town. An exploratory phase, in which inductive ethnographic methods were used to explore the nuances of ‘agency', ‘capability' and ‘collective empowerment' that occur through technological dealings was followed by a still ongoing design phase, in which the two communities are involved in co-designing new ICT services that support their community activities. The assessment phase, which is directed towards the formulation of theoretical and design considerations, will look towards a participative evaluation process and a sustainable patterns.
Using Insights from Learning Journals to Rewrite Teaching and Learning Goals in Student-Friendly Language
Authors: Vilceanu M. Olguta
Published: August 2015

Understanding the course mission and learning goals is an essential step for students in any learning environment. Reflective writing assignments may assist instructors in their quest to reformulate teaching and learning goals in a language accessible to students, while maintaining the mission and intent of the class relevant to their professional field and requirements. This study proposes using software-driven content analysis methods borrowed from media and communication research in an attempt to first identify the degree and manner in which students internalize the language of instruction; and second, rewrite course/training materials in a language that reflects student discourse. Because it can use either free-form or formal writing, this strategy can be adapted for a variety of interdisciplinary contexts.
A Template for Design Personas
Authors: Nielsen Lene , Hansen Kira Storgaard , Stage Jan , Billestrup Jane
Published: August 2015

The persona method is gaining widespread use and support. Many researchers have reported from single cases and from novel domains on how they have used the method. However, the way companies and design groups describe personas has not been the focus of attention. This paper analyses 47 descriptions from 13 companies and compares these to an analysis of recommendations from 11 templates from literature. Furthermore, 28 interviews with Danish practitioners with experience in using personas are analyzed for content on persona descriptions. The study finds that a Danish persona style has developed that is different from the recommendations in the lack of marketing and business related information and the absence of goals as differentiator for personas. Furthermore, the inspiration and knowledge on personas originates from co-workers and seminars and not much from literature. This indicates that the community of practice influences the persona style.
Short Term Electric Load Forecasting with Back Propagation Neural Network and Simulated Annealing Genetic Algorithm
Authors: ul Islam Badar , Baharudin Zuhairi , Nallagownden Perumal
Published: August 2015

Although, Back Propagation Neural Network are frequently implemented to forecast short-term electricity load, however, this training algorithm is criticized for its slow and improper convergence and poor generalization. There is a great need to explore the techniques that can overcome the above mentioned limitations to improve the forecast accuracy. In this paper, an improved BP neural network training algorithm is proposed that hybridizes simulated annealing and genetic algorithm (SA-GA). This hybrid approach leads to the integration of powerful local search capability of simulated annealing and near accurate global search performance of genetic algorithm. The proposed technique has shown better results in terms of load forecast accuracy and faster convergence. ISO New England data for the period of five years is employed to develop a case study that validates the efficacy of the proposed technique.
Modeling and Simulation of Power Electronic Distribution Transformer Based on a Three Level Converter
Authors: Ahmed K.Y. , Yahaya N.Z. , Asirvadam V.S. , Ibrahim Oladimeji
Published: August 2015

In this paper, a new type of power electronic distribution transformer (PET) has been introduced based on the power electronics converter on the primary and secondary sides of the transformer. This PET has three stages and the input stage has a three-level, three-phase rectifier. The middle stage has two three-level single-phase converters and a high-frequency transformer; and, the output stage is a three-phase, two-level inverter. This power electronic distribution transformer provides many advantages, such as power factor improvement, reactive power compensation, eliminating harmonics, and controlling and protecting itself (PET) with minimum size, compared to the traditional transformer. The MATLAB/Simulink was used to analyze and validate the power electronic distribution transformer.
Alternative Solar-Battery Charge Controller to Improve System Efficiency
Authors: Sabry Ahmad H. , Wan Hasan Wan Zuha , Zainal Mohd , Amran Mohd , Shafie Suhaidi B.
Published: August 2015

When the heat losses sense is adopted for some solar system and power conversion components in residential building application, it is benefit to use those losses, that are consequently acts inversely on system efficiency, as a useful energy to modify the performance of that system instead of dissipated. In terms of efficiency of solar-battery charge controller, power dissipation is always associated with every power component and the losses would be either results from switching and conducting components or from the OFF state of the main switching component. This paper proposed a high efficiency solar-battery charge controller as an alternative to the main solar charge controller in most conventional residential solar system , the concept of the proposed controller circuit based on using the off state energy duration as well as that power losses coming from the main switching component and complexity of the conventional controller, and using this energy in a separate current path to energize an auxiliary battery or directly load used to cool or even to ventilate the system components causing in improving its performance. This will leads to electronic circuit with low losses as a compared with the conventional charge controller to be a part of the integrated and automated building solar system, the design has an algorithm based on some environment parameters like sun Irradiance and weather temperature, this algorithm seems to be inversely calculated because its start from the value of full charge battery voltage. A Simulink Matlab simulator is attempted in the simulation phase of this research as well as an experimental data has been collected to verify the circuit function and energy saving goal.
Application of Robust Control on Arduino Microcontroller Testing in Power Electronics Converters
Authors: Zulkifli Shamsul Aizam , Tomari Mohd Razali , Hussin Mohd Najib , Saad Abdul Salam , Ab Ghani Mohd Khairul Akli , Deraman Farih , Berahim Nawi , Abdullah Abdul Hadi
Published: August 2015

This paper presents the capability of Arduino for responding to the robust controller which has been applied to the 3 phase rectifier and 3 phase inverter. The interface between the converters and the Arduino has been established by using MATLAB-Simulink environment. This is the fastest interface due the Arduino library that is available in the MATLAB which can be used before downloading the program to the board. Two types of controllers have been tested which are, P-Resonant and Fuzzy-PI controller. The voltage or current feedback mechanism also has been applied between the converters with the Arduino input port in order for responding to the design controller for signal generating pattern. At the end, it shows that, the Arduino is capable to receive the signals from the converters, process the signals in the board and generating the signal out for controlling the converters.
Single-Phase Single Stage String Inverter for Grid Connected Photovoltaic System
Authors: Mohammad Noor Siti Zaliha , Omar Ahmad Maliki , Radzi M.A.M.
Published: August 2015

This paper presents the development of single-phase single stage string inverters for grid connected photovoltaic system. The inverter is designed to generate an AC current in phase with the grid voltage and to extract the maximum power from the PV array. The maximum power point tracking (MPPT) is achieved by adjusting the modulation index and phase angle of the inverter’s voltage accordingly using fuzzy logic control algorithm. The prototype system is tested using 2 series of STP170s-24/Ac PV modules. Insulated Gate Bipolar Transistors (IGBTs) are used as power switches while the Sinusoidal Pulse Width Modulation (SPWM) scheme is used as the switching technique to synthesize the output waveform. Simulation model was developed in MATLAB/Simulink environment to study and evaluate behavior of the proposed converter. The results of the prototype system show good agreement with the simulation model.
Comparison between PSO and FLC: MPPT for Energy Harvesting of PV System under Partial Shading Condition
Authors: Kamarzaman Nur Atharah , Ramli S.S. , Samat A.A.A. , Tajudin Aimi Idzwan
Published: August 2015

Conventional Maximum Power Point Tracking (MPPT) controllers are widely used due to simple implementation and show a good performance in tracking Maximum Power Point (MPP) when solar irradiance is uniform. However, when partial shading occurs on the PV array, tracking to MPP becomes complicated as multiple peaks exist on the Power-Voltage (P-V) characteristic curve. Several methods based on stochastic algorithm and artificial intelligence has been developed to track true MPP under partial shading conditions. This paper focuses on the performance of MPPT controller to extract maximum power from PV system under partial shading condition. The selected MPPT algorithms that have been implemented in the PV system include Fuzzy Logic Controller and Particle Swarm Optimization. Results show that both the simulated MPPT controllers are capable of tracking the maximum power.
A Comprehensive Study of Improved Evolutionary Particle Swarm Optimization (IEPSO) for Network Reconfiguration with DGs Sizing Concurrently
Authors: Napis Nur Faziera , Sulaima Mohamad Fani , Abd Kadir Aida Fazliana , Gan Chin Kim , Mohd Dahalan Wardiah , Sulaiman Marizan
Published: August 2015

This paper deals with the reconfiguration of the distribution network system to investigate the total power losses considering Distribution Generations (DGs) sizing concurrently. To overcome other limitations and enhance the solution performances, a new optimization approach called Improved Evolutionary Particle Swarm Optimization (IEPSO) is proposed. The primary aim of this study is to investigate the contribution of the proposed algorithms towards total power losses by considering the optimum DG size simultaneously. The proposed method is compared with the traditional Particle Swarm Optimization (PSO) and Improved Particle Swarm Optimization (IPSO) respectively. The amount of time that an algorithm spends in obtaining an alternative topological status for the system power loss reduction and distribution generation sizing is taken into consideration. In this context, the study is tested using IEEE 33 bus distribution system.
Comparison between Takagi Sugeno FIS and PI Controller: An Adaptation Scheme of MRAS for Speed Sensorless Control of PMSM
Authors: Abd Samat Ahmad Asri , Ishak Dahaman , Iqbal Shahid , Tajudin Aimi Idzwan
Published: August 2015

— This paper proposes modification of an adaptation scheme which aims to replace the conventional PI controller for MRAS by using Fuzzy Logic Control (FLC). This FLC based on Takagi-Sugeno Fuzzy Logic Inference System (FIS). To achieve this goal, field oriented control (FOC) method has been utilized to control the speed of PMSM with the implementation of MRAS to observe the rotor position and speed of the motor. PMSM becomes the reference model for MRAS while the current model in the rotor reference frame is set as the adjustable model. The Takagi Sugeno Fuzzy FIS is executed in the MRAS adaptive scheme in order to tune the errors between the reference and adjustable model. The effectiveness of the Takagi Sugeno FIS to tune the errors in MRAS scheme is compared with the conventional PI controller. The proposed method clearly indicates improved motor performance over a wide range of operating speeds since is capable of tracking the motor speed effectively.
Simulation and Practical Analysis on Power Factor Correction Techniques for Welding Applications
Authors: Thiruvenkadam Madhulingam , Thangavel Subbaiyan , Paramasivam Shanmugam
Published: August 2015

The most of the industrial welding applications involving of electronic circuits such as AC-DC, and DC-AC and AC-DC converters. The input power factor of such a system is reduced due to the presence of more harmonics due to the non-linear devices within the converters which leads to creates more adverse effects. There by a need of suitable AC-DC converter with power factor correction technique to condition the supply current. The power factor correction rectifier that requires best current control from i) Peak current control ii) Average current control and iii) Hysteresis current control. This paper presents a comparative analysis from above mentioned power factor correction control topologies. The simulation of these control techniques are carried out using “Plecs” with “MATLAB/SIMULINK”. The simulation results shows that Hysteresis control has low THD, good DC link voltage regulation and better performance than other control techniques. The same control technique is implemented in TMS320F2812 DSP and results are proved.
Online Monitoring System for Domestic Distribution Box
Authors: Hau Tan Jen , Nor N.M. , Ibrahim T. , Daud H.
Published: August 2015

A new method for monitoring and control of domestic distribution box is proposed and developed for automated recovery of power continuity during interruption. The system automatically test each of the sockets to determine the source of the failure and isolate them. The data of the modified connection will be sent to the client through a server, wirelessly to notify the user the modifications made. Parallel processing via multi-threading in the server are used to increment the upper limit of TCP transmission's throughput. Multiple SQLite database are used by multiple threads for parallel storage of data to increase performance.
Efficiency Comparison of Trapezoidal and Sinusoidal Method for Brushless DC Motor Drive
Authors: Abu Hassan Mohd Arif , Abdullah Abdul Rahim , Bahari Nurhazilina , Mohd Sabri Muhammad Ihsan
Published: August 2015

This paper compares overall efficiency of trapezoidal BLDC motor which is excited by trapezoidal drive and sinusoidal drive. The different characteristics and performance of trapezoidal Brushless DC (BLDC) motor is formed by driving methods. Sinusoidal drive that excites trapezoidal BLDC motor generates greater maximum torque than trapezoidal drive. However, with regard to high frequency loss caused by a pulse width modulation (PWM) carrier and switching loss, the trapezoidal drive has potential to achieve higher efficiency than the sinusoidal drive. Thus, these two drive methods excite trapezoidal BLDC motor are compared to study the efficiency performance. The motors drives are simulated by using MATLAB and their efficiency are measured. The results show that the trapezoidal BLDC motor with trapezoidal drive has higher efficiency compared to trapezoidal BLDC motor with sinusoidal drive.
Investigating the Impact of Distributed Generators Power Factor to Simultaneous Optimization Analysis
Authors: Jamian Jasrul Jamani , Mustafa M.W. , Abdullah Mohd Noor
Published: August 2015

This paper discusses the optimal Distributed Generator (DG) coordination using the Particle Swarm Optimization (PSO) technique where the DG output and location are determined simultaneously. Furthermore, this study analyzes both single DG and multiple DGs configurations. The influence of DG Power Factor (PF) to the optimal DG placement and the DG output are investigated by varying the DG PF values. Specifically, the PF were configured to five values, which are 0.8, 0.85, 0.9, 0.95 and 1.0. From the results, the optimal DG placements are similar, regardless of the PF condition. For example, in the single DG unit experiment, the optimal DG location is at bus 6 whilst in the triple DG units test, the optimal locations are at busses 14, 24, and 30. In contrast, the value of PF significantly influences the optimal DG output and power loss reduction. This study concludes that the design with three DGs where their PFs are configured to 0.8 has the least power loss.
Modeling and Analysis of Linear Permanent Magnet Generator for Wave Energy Conversion Using Finite Element Method
Authors: Memon Aamir Hussain , bin Ibrahim Taib , Nallagownden Perumal
Published: August 2015

This paper presents the design modeling and analysis of linear permanent magnet generator for wave energy conversion using finite element method. The time-stepping finite element technique is used to determine electromagnetic characteristics and analyze the efficiency. The main parts such as; copper loss is analyzed on the different variation of winding input excitation and the core loss is determined based on various specific loss curves data in order to analyze its effect on frequency. The influence of main dimension of stator is analyzed on electromagnetic characteristic and copper loss.
Influence of Leading Design Parameters on the Performance of a T-Shaped Permanent Magnet Tubular Linear Motor
Authors: Abdalla Izzeldin Idris , Ibrahim Taib , bin Mohd Nor Nursyarizal
Published: August 2015

This paper deduces from Finite-Element Analysis (FEA), the influence of leading design parameters on the performance of a novel T-shaped permanent magnet (PM), quasi-Halbach magnetized tubular linear motor. The proposed motor is designed and developed for small reciprocating applications. In order to obtain the maximum power density, a two-dimensional Finite-Element model is developed to investigate the performance of the proposed machine. The proposed T-shaped PM structure has a higher power density as compared to the conventional rectangular-shaped PM structure. The losses of the motor, such as copper loss and iron loss, as well as the efficiency, are established as functions of a set of motor leading design parameters. It is shown that the developed motor produce satisfactory output power, around 85 W, which is enough to operate the direct-drive reciprocating compressor of a household refrigerator.
Simulation Study on HST Distribution for ONAN Oil-Filled Transformer
Authors: Muhamad Nor Asiah , Kamarden Hanafiah
Published: August 2015

Advanced monitoring system and preventive maintenance introduced on serviced transformer successfully reducing the equipment malfunction and breakdown rate. However, faults that occur and developed inside the transformer can be very unpredictable. One of the measures can be taken is to analyse the hottest spot temperature (HST) of the transformer, because high temperature will affect transformer insulation system performance and its life-span. HST distribution study on the transformer surface body can give better understanding on how HST will behave at inner and outer transformer surface tank, so that it can be correlated to the actual temperature inside the transformer. Therefore, this paper presents a simulation study on 100 KVA ONAN oil-filled type of distribution transformer with three types of HST intensity. Result shows that temperature distribution projectile is tending to go upwards in the insulation oil and inward into the winding. Moreover, location of HST can be identified by comparing the temperature distribution plot with and without HST.
2D-FEA Based Design Study of Salient Rotor Three-Phase Permanent Magnet Flux Switching Machine with Concentrated Winding
Authors: Jenal Mahyuzie , Sulaiman Erwan , Khan Faisal , Ahmad Md Zarafi
Published: August 2015

This paper presents a new structure of permanent magnet flux switching machine (PMFSM) with multiple different sizes of rotor pole width. A robust single piece salient rotor is used to modulate and switch the flux linkage polarity in the armature winding and become the fundamental mechanism of these types of machines. The methodology of two-dimensional (2-D) finite element analysis (FEA) is used to evaluate the electromagnetic performance of coil test including flux line distributions, three phase flux linkage, cogging torque as well as induced emf. The resulting performances are analysed based on the variety of rotor pole width to meet the requirement of direct drive propulsion of Electric Vehicles (EVs).
Design and Improvement of 12S-14P Hybrid Excitation Flux Switching Machine with Field Excitation Coil in Radial Direction
Authors: Rahimi Siti Khalidah , Sulaiman Erwan , Jafar Nurul Ain
Published: August 2015

This paper presents a new design modification of Hybrid Excitation Flux Switching Machine (HEFSM) in which the initial Field Excitation Coil (FEC) in theta direction is replaced with FEC in radial direction. Obviously, the new design has advantages of preventing flux cancellation between FEC and armature coil windings. With similar design restrictions and specifications of existing electric motor used in traction drive applications, initial performances of the proposed HEFSM are evaluated based on 2D-FEA. Design modification by using deterministic optimization approach is conducted in effort to achieve the optimum performances. After several cycles of iteration, the improved HEFSM with FEC in radial direction has achieved torque and power of 304.8Nm and 130kW, respectively.
Comparison of EPSO, PSO and EP Approaches in Transmission Loss Minimization in Power System Network
Authors: Jumaat Siti Amely , Musirin Ismail , Rahmat Nur Azzamudin
Published: August 2015

The paper presents a comparison of Computational Intelligence techniques are Evolutionary Programming Swarm Optimization (EPSO), Particle Swarm Optimization (PSO), Evolutionary Programming (EP) to optimal placement and sizing of Static Var Compensator. The technique has been implemented to minimize the transmission loss and improve the voltage profile of the system. Simulation performed on standard IEEE 118-Bus RTS and indicated that EPSO a feasible to achieve the objective function.
Design and Modelling of a Portable Pico Linear Generator for Wave Energy Conversion System
Authors: Mohammad Naafi Muhammad Faris , Ibrahim Taib , Mohd Noor Nursyarizal , bin Mohamad Hamim Muhammad Aizuddin Firdaus
Published: August 2015

This paper will focus on designing and modelling the portable pico linear generator for the wave energy converter application. The aim for this research is to develop a permanent magnet linear generator which has the weight less than 20 kg and can produce up to 80 W. A thorough literature review has been done on type of configurations, stator structure, magnetization and type of cored to select the best features of the linear generator. Three proposed designs of the permanent magnet linear generator is presented and each of the proposed design performance is simulated using the Ansys Maxwell software. Comparison on the preliminary result such as the air gap flux distribution, back-emf, flux linkage and thrust force of the three proposed designs will be shown and discussed.
Partial Discharge Pulse Propagation and Attenuation in Power Cable Insulation: Simulation in Finite Element Method
Authors: Illias Hazlee Azil , Tan Yan Fen , Bakar A.H.A. , Mokhlis Hazlie
Published: August 2015

Travelling wave method is commonly used for partial discharge (PD) location since the past. However, for a long cable, the attenuation of PD pulse propagation could be significant. This is due to more energy loss during the propagation of pulse, which can affect the sensitivity of the PD source location within cable insulation. In this work, PD pulse propagation along cable insulation from the defect site was modelled using finite element analysis (FEA). The model was used to simulate the electric field distribution in the cable insulation due to the PD pulse propagation and to calculate the attenuation constant. The effect of cable length and PD source location in the cable insulation on the attenuation constant was also studied. Through this work, a better understanding of PD pulse propagation and attenuation constant using the FEA model geometry that has been developed can be attained.