bluuebunny/crossref_metadata_2025 huggingface dataset:
GASTRIC ANTIULCER AND ULCER HEALING EFFECTS OF PUNICA GRANATUM L. PEEL EXTRACT IN RATS: ROLE OF OFFENSIVE AND DEFENSIVE MUCOSAL FACTORS AND OXIDATIVE STRESS
Authors: Chauhan Indal , Sharma Ankita , Gangwar Mayank , Gautam Manish Kumar , Singh Amit , Goel Raj Kumar
Published: May 2017

Objective: The present work incorporates the study of gastric antiulcer and ulcer healing effects of dried Punica granatum (PG) peel 50% ethanol extract (PGE) in rats.Methods: PGE (100 mg/kg) was administered orally once daily to rats either before or after induction of gastric ulcers (GU) for 7 d. Antiulcer effects of PGE were seen against acute GU, induced by pylorus ligation (PL), cold restraint stress (CRS), aspirin and ethanol while, ulcer healing in acetic acid (AA)-induced chronic GU in rats. Ulcer index (UI), gastric juice volume, acid-pepsin and mucin secretions and gastric mucosal glycoproteins, free radicals (LPO and NO) and antioxidants (SOD and GSH) were estimated.Results: PGE showed a decrease in UI in all GU models (45.6 to 79.7%, P<0.05 to P<0.001) indicating both protective and healing effects. PGE showed little or no effects on volume, acid-pepsin concentration and output but increased mucin secretion (55.1%, P<0.05) and mucosal glycoproteins (35.7%, P<0.05) in PL rats. CRS rats showed an increase in LPO and NO (48.4 to 58.3%, P<0.01) and SOD (21.8%, P<0.01) but decrease in GSH and CAT (33.1 to 44.8%, P<0.01 to P<0.001) compared with unstressed rats. PGE-treated CRS rats showed a decrease in LPO and NO (44.1 to 61.2, P<0.01 to P<0.001) and SOD (13.2%, P<0.01) and increase in GSH and CAT (43.8 to 48.7%, P<0.01 to P<0.001) compared with CRS rats.Conclusion: PGE seemed to have ulcer cytoprotective effects due to enhanced mucosal resistance and reduction in oxidative mucosal damage possibly via high antioxidant activity.
Boundary-layer flow and heat transfer of cross fluid over a stretching sheet
Authors: Khan Masood , Manzur Mehwish , Rahman Masood
Published: May 2017

The current study is a pioneering work in presenting the boundary-layer equations for the 2-D flow and heat transfer of the Cross fluid over a linearly stretching sheet. The system of PDE is turned down into highly non-linear ODE by applying suitable similarity transformations. The stretching sheet solutions are presented via. a numerical technique namely the shooting method and graphs are constructed. The impact of the emerging parameters namely the power-law index, n, the local Weissenberg number, We, and the Prandtl number on the velocity and temperature fields are investigated through graphs. The numerical values of the local skin friction coefficient and the local Nusselt number are also presented in tabular form. Additionally, the graphs are sketched for the local skin friction coefficient and the local Nusselt number. It is observed that with growing values of the local Weissenberg number the velocity profiles exhibited a decreasing trend while opposite behavior is seen for the temperature field. Further, comparisons are made with previously available literature for some limiting cases and an excellent agreement is achieved.
Influence of an integrated maintenance management on the vehicle fleet energy efficiency
Authors: Vujanovic Davor , Momcilovic Vladimir , Medar Olivera
Published: May 2017

Integrated fleet maintenance management represents implementation of measures, actions and decision making with the aim of decreasing total maintenance costs and increasing energy efficiency fulfilling requirements of three interdependent components: transport, maintenance and their environment. Therefore, a methodology for integrated fleet maintenance management is developed and presented in this paper. The purpose of the methodology is to contribute in increasing fleet?s energy efficiency and evaluate managers? fleet maintenance management efficiency. The methodology was implemented in the company with own light and medium goods vehicle fleet. According to realized values of defined indicators, the maintenance management has become more efficient in the observed period. It contributed to specific fuel consumption reduction per transport volume, thereby increasing fleet?s energy efficiency. Further, the fleet size was reduced, which affected the rational realization of the given transport volume in the observed period.
A Virtual Power Plant with the use of the Energy Box in a Smart Grid concept
Authors: C. S. Ioakimidis  , L. Oliveira  , K. N. Genikomsakis  , P. Rycerski
Published: May 2017

Recent years have witnessed considerable advances in designing and operating of energy grids, while the concepts related to the operation of Smart Grids, Vehicle-to Grid, responsive demand, among others, are gaining research interest worldwide. From an educational viewpoint, the use of a complementary laboratory approach is expected to contribute to the effective communication of these concepts to the students of engineering courses at university level. To this end, this work presents the development of a virtual lab for educational purposes, simulating the operation of a Virtual Power Plant in a Smart Grid context. The system under study involves renewable energy generation, controllable loads and local electricity storage options from electric vehicles, while allowing the students to experiment with the system parameters and perform real-time monitoring and control of the system operation.
Wind Power and Electricity Consumption Forecasting on a Smart House Location
Authors: H. Eliasstam  , K. N. Genikomsakis  , C. S. Ioakimidis
Published: May 2017

This paper presents the use of an artificial neural network for classification on a residence house that uses wind and electricity consumption predictions to identify patterns at the desired location, in order to obtain a stochastic distribution of the daily wind and electricity profile. This is a step on the further creation of a short-term operation model that allows determining the technical and economic impact of stationary/mobile batteries of electric vehicles in presence of microrenewables along with the electricity consumption. This short-term operation model will be in the day-ahead perfect market operation (unit commitment) where specific changes are made to consider stationary and mobile operation.
Accuracy and Data Compression Trade-Offs for Power Quality Disturbance Representation with DWT and PCA techniques
Authors: L.B. Soares  , R. E. Dapper  , C. Crovato  , S. Bampi  , A. A. Susin
Published: May 2017

This paper analyses and compares different digital signal processing techniques to capture with fidelity the power lines disturbances. The benefits and shortcomings of both Discrete Wavelet Transform (DWT) and Principal Component Analysis (PCA) techniques are assessed. Their implementation, application and test-cases with recorded power signals are described in the paper. We define the data compression ratio (or efficiency) and the signal reconstruction accuracy after compression as the main criteria for comparing these techniques. In this paper the trade-offs of accuracy in the disturbances representation and compression efficiency were exploited. After systematic comparisons, our experimental results have shown shortcomings of the DWT and PCA techniques not yet addressed in previous works.
Construction and Comparison of the Efficiency of Water Heating Systems using low Cost Solar Collectors
Authors: Marcelo G. Martins  , Francisco X. L.  Silva  , Antonio M. J. C. Neto  , Gabriel G. da Silva  , Francisco das  Chagas Marques  , Nélio T. Machado
Published: May 2017

This work describes the manufacture of two solar water heating (SWH) systems, one using polyvinyl chloride (PVC) pipes and the other using PVC plates, both with approximately the same area of collecting solar thermal energy. The aim is to analyze their efficiencies and discuss physical concepts and their practical applications. Both SWH collectors were placed side by side under the sun, such that they were submitted to the same climatic conditions. This work also draws attention to the importance of using solar radiation1 as an alternative and sustainable source of energy for water heating.
A Three-Phase Microgenerator Based Solution for Power Harvesting Applications
Authors: M. Alves  , J. M. Fonseca  , J.M. Dias Pereira
Published: May 2017

With the fast growth of wireless communications between nodes/sensor units, devices installed in remote places require continuously energy supply for their functionality or communication requirements. For these applications energy harvesting takes place as a good solution to increase the availability of energy, in opposition to the conventional systems of energy supply. Regenerative energy sources like thermoelectric, magnetic, piezoelectric, and/or renewable sources such as photovoltaic and wind, among others, allowed the development of different powering solutions for sensor units. The purpose of this work is to characterize a three-phase micro generator that is used to convert the energy extracted from wind or water flow, among others mechanical energy sources, to electrical energy. The study is carried out taking into account the velocity of axis versus power provided to a load.
OPTIMIZATION OF BIODIESEL PRODUCTION PROCESS FOR HOMOGENEOUS CATALYSIS FROM USED COOKING OIL
Authors: C. Guerrero  , J. Parra  , F. Sierra
Published: May 2017

It is well known that the used cooking oil (UCO) is responsible for the high pollution found in groundwater, fact that leads to increase treatment cost of wastewater, moreover, the environmental problems produced by the use of diesel fuel increase the need of seeking alternatives to decrease this problems by means of the reuse of UCO, finding a cleaner alternative fuel. Biofuel such as biodiesel is considered as one of this alternative having environmental advantage due to decrease of pollutant emissions in diesel engines. Biodiesel from UCO is produced throughout the transesterification reaction, using alcohol and a catalyst. This paper reports the effect of temperature, alcohol/oil molar ratio, and catalyst amount used over the yield of the transesterification reaction using oil from hotel industry. The homogeneous catalysts was based in NaOH from 0.5 and 0.7% by weight, the range operation temperatures were between 50 and 60 °C, with molar ratio alcohol / oil 6/1 and 9/1. Quite high yield values were shown, among 83 and 95%, with a statistical error of less than 0.5.
Financial Analysis for a Multi-Carrier Energy System Equipped with CCHP
Authors: A. Sheikhi  , Sh. Bahrami  , A.M. Ranjbar  , S. Sattari  , M. Adami
Published: May 2017

The interest on distributed generation has been increasing in recent years, especially due to technical development on generation systems that meet environmental and energy policy concerns. One of the most important distributed energy technologies is Combined Cooling, Heat and Power (CCHP) systems. CCHP is a small and self-contained electric, heating and cooling generation plant that can provide power for household applications, commercial or industrial facilities. It can reduce power loss and enhance service reliability in distribution systems. Since the input of a CCHP system is natural gas then natural gas price is so important in CCHP penetration level in DG’s market. In this paper authors by considering gas price, capital cost and also sales revenue, find the effects of these parameters in financial parameters for a multi-carrier energy system with optimal size and operation by applying COMFAR III software.
Cross-sectional temperature field of a solar collector’s absorber in the case of annular pipe
Authors: P. Shipkovs  , G. Kashkarova  , K. Lebedeva  , M.Vanags  , A. Snegirjovs  , V.Barkans
Published: May 2017

In households, solar collectors are finding ever increasing use for hot water preparation. Although the design of solar collectors is relatively simple, the authors over many years concentrate attention on modelling the cross-sectional temperature field of the solar collector’s absorber [1-7]. In solving the cross-sectional temperature field for an annular pipe [1], the periodical cross-sectional domain is divided into three sub-domains where the first sub-domain is the plate between pipes, the second – a pipe’s wall, and the third – the liquid; as a result, the temperature field expressions have been obtained for all the three sub-domains. In works [2, 3] the temperature fields obtained were simplified. To define its variations in time, the temperature field was found by solving the Laplace equation under non-stationary time-dependent conditions [4]. The obtained results evidence that the non stationary conditions might not be taken into account in long- lasting sunny weather, while such non-stationarity changes considerably the temperature field when it is short-term (e.g. in cloudy weather). The temperature has also been found for a square-pipe absorber [7] as more technological in design. In the present work, the final temperature field model is proposed for the absorber of a round-pipe collector. As distinguished from [1], in this work the temperature of liquid is assumed to be constant over the entire pipe cross-section. Such an assumption significantly simplifies the calculation while not changing the physical essence.
i-Sare. The Future Grid.
Authors: L.G. Corzo  , I. Cerro  , E. Sansinenea  , G. Santamaria  , J. Zubizarreta  , L. Arrizubieta
Published: May 2017

This paper presents a real implementation of hierarchical control scheme for a smart grid equipped with voltage source converters, attached to renewable and conventional energy generators and storage systems based on ultracapacitors, flywheel and batteries, which is able to assume the demand of domestic, commercial, industrial and electric vehicle demanding current loads up to 400 kw in islanded mode or connected to the main grid. The hierarchical control used is implemented in the central control system and in each of the converters connected to the intelligent grid, in order to distribute the control over all the elements involved in the generation of energy. For this purpose it is used a distributed communication architecture based on EPICS to manage all the information generated. This micro grid, called i-Sare, was developed during the 2012 and beginning of 2013, and will be operational in Donostia (Gipuzkoa) at the end of 2013. In this paper real test results are presented to demonstrate the effectiveness of the control and the communication architecture used in iSare.
Study of Dynamic Viscosity and Density of Aprotic Solvents for Lithium – ion Batteries
Authors: M. Frk  , J. Maca  , Z. Rozsivalova
Published: May 2017

The article deals with description of rheological properties of solvents for electrolytes of lithium-ion accumulators. Solvents mixture of dimethyl sulfone and sulfolane at different volume ratios and with a lithium salt (LiClO4) appear as potentially suitable electrolyte. The aim of this experiment is to investigate the rheological properties, particularly density and dynamic viscosity, of solvents with lithium salt in temperature dependence and to find the optimal composition of the electrolyte from the perspective of achieving the lowest dynamic viscosity and better electrical conductivity because both quantities are closely related in accordance with Walden’s rule. The vibration method is used to determine the values of dynamic viscosity.
Test rig for stand-alone small power wind turbine emulation for variable wind and load
Authors: C. Vlad  , A. Burlibaa  , T. Munteanu  , G. Gurguiatu  , M. Barbu
Published: May 2017

This paper presents futures from experimental investigation of an autonomous small power wind system. The envisaged wind system is based on a PMSG (Permanent Magnet Synchronous Generator) directly connected to the wind turbine shaft, while the DC output load is supplied by a rectifier and a chopper. The DC load is considered as a resistive load with wide values range. Experimental investigations are provided in partial load regime. The power optimization is performed through a power loop in two ways: by controlling the electrical power or by controlling the electromechanical power. For the above two situations it is shown how the optimization power loop reference and power loop feedbacks can be set, in order to obtain maximum electrical power, for each wind speed value corresponding to the partial load regime. It was also highlighted that for a wide range of DC load values the mechanical and electrical powers are not constant as it should be corresponding to the mathematical model of the optimal conversion. This is due to mechanic-electrical subsystem processes. The electrical power variation range with the load should be provided by the manufacturer in the low-power wind system data sheet.
Application of a Hybrid Energy System Combining RES and H2 in an Office Building in Lavrion Greece
Authors: I. Paspaliaris  , M. Taxiarchou  , A. Peppas  , P.G. Benardos  , S. Carosio  , G. Urbano  , A. Monero  , R. De  Laurentiis
Published: May 2017

In the framework of the H2SusBuild project, a prototype hybrid energy system combining Renewable Energy Sources (RES) and hydrogen (H2), as energy storage material and as a green fuel, has been designed, installed and is currently in operation in Lavrion, Greece. The system comprises thin-film PV panels, wind turbines, a water electrolysis unit, a H2 compressor, a micro-CHP unit (PEM fuel cell) and a H2 burner. The aim of this system is to cover the energy needs of a ≈500 m2 office building and to render it a self-sustained, zero CO2 emission installation. The entire site is operated through an advanced Energy Management and Control System (EMCS), responsible for monitoring magnitudes of interest (for example power, energy, stored H2 volume etc.) and managing the synergistic operation of all components based on a custom developed control algorithm. This paper’s aim is to present the results of system operation and evaluate the performance of key components based on data collected during system operation under real conditions. The results show good efficiencies for all major system components and that the implemented control algorithm achieves the zero CO2 emissions goal.
Field Measurement Based PLS Model for Dynamic Rating of Overhead Lines in Wind Intensive Areas
Authors: S. Abdelkader  , D. J. Morrow  , J. Fu  , S. Abbott
Published: May 2017

This paper presents results of lab tests, field measurements and mathematical modelling for the Dynamic Rating (DR) of Over Head Transmission Line (OHTL) in a wind intensive area. In this paper, DR is done by developing a statistical line model. This model is based on Partial Least Squares (PLS) multi regression. DR provides extra capacity to the line, over the traditional seasonal static rating, which makes it possible to defer the need for reinforcement the existing network or building new lines.
On the Possibility of Using CHP From a 1.4MW Direct Fuel Cell at Kettering University Engineering Building – A Demonstration Study
Authors: Etim U Ubong  , Uwem Ubong  , Vipul Laddha  , Pouyan Pourmovahed
Published: May 2017

The concept of using a distributed power generation and a combined heat and power principle – CHP in public buildings, commercial facilities is widely gaining public acceptance as a result of reduced energy cost, reliable power supply and environmental and health issues. By using the exhaust heat from a high temperature fuel cell at 400 oC for cogeneration, space heating, to provide warm water for facility use - (swimming pool and sporting locker room) and cooling in chillers at no additional cost, we reduce energy cost and preserve the environment. By bottoming cycle, the efficiency of the entire system is increased. A study is conducted to compare the economic impact of using the CHP system against the conventional heating system using furnaces.
Combined Heat and Power (CHP) studies at the Flint Bio-Gas Complex Using a 1.4 MW Direct Fuel Cell – A Demonstration Study.
Authors: Etim U. Ubong  , Uwem Ubong  , Vipul Laddha  , Pouyan Pourmovahed
Published: May 2017

Future energy systems should include distributed power generation with combined heat and power. A study is conducted to evaluate the economic competitiveness of using a high temperature fuel cell with combined heat and power as a distributed power generation system against the conventional grid supplied power system at a sewage treatment facility. This report evaluates the economic benefits of using natural gas or biogas from the sewage treatment plant at the Flint-Biogas Complex to power a 1.4MW direct fuel cell which operates at a temperature of 400 oC. The waste recovery heat will be used for heating the sludge and the facility. Bottoming cycle options are proposed. The waste heat will be used to warm the sludge, heat up the reactants and provide warm water throughout the facility. This approach eliminates or reduces additional energy cost. The most important engineering and economic indicators would be used for evaluating the CHP system against the conventional furnace and power from the grid.
Wind speed forecasting using Singular Systems Analysis
Authors: C. Skittides  , W.-G. Früh
Published: May 2017

We report on a method to predict wind speeds up to 24 hours ahead using a technique originating in Dynamical Systems and Chaos theory using a signal processing technique known as Singular Systems Analysis. The method predicts wind speeds based on a set of previous measurements which were used to construct an attractor in an optimally defined phase space as a ‘training set’. Current wind measurements can then be projected to onto that phase space to find most similar previous measurements. By tracing the evolution of these similar previous data, it is possible not only to forecast the wind speed but also to obtain a measure of the expected forecasting uncertainty. The method was applied to a set of hourly wind speed data from a UK Meteorological Office weather station near Edinburgh. A comparison with a simple persistence prediction showed that the Singular Systems Analysis was both, consistently better at predicting wind speeds between 12 and 24 hours ahead than persistence, and also able to provide a meaningful forecasting uncertainty.
Electric Power Generation Using Buoyancy-Induced Vortices
Authors: Mark W. Simpson  , Arne J. Pearlstein  , Ari Glezer
Published: May 2017

Thermally-stratified air layers over solar-heated ground are exploited for scalable, low-cost power generation by the deliberate formation of intense buoyancy-induced vertical columnar vortices. Such vortices entrain the ground-heated air layer in regions with high surface solar heating rates, and convert the (gravitational) potential energy into “solar-induced wind” with significant kinetic energy. Unlike naturally occurring “dust devil” vortices, these columnar vortices are deliberately triggered and anchored. Each vortex is sustained by continuous entrainment of ground-heated air through an azimuthal array of stationary ground-mounted vertical vanes. Electric power is generated by using the rotational and vertical air motions within the columnar vortex to drive a vertical-axis turbine. Meter-scale laboratory experiments have demonstrated the nucleation, anchoring, and sustainment of strong, buoyancy-driven vortices centered within an azimuthal array of stationary vertical vanes above a controlled thermal ground plane. Outdoor tests of a meter-scale prototype have demonstrated autonomous start-up, formation, anchoring, and sustainment of a buoyancy-induced vortex generated solely by absorbed solar energy.
Comparison of the Harmonic Distortion of Current Source and Voltage Source Inverters
Authors: S. König  , G. Herold
Published: May 2017

This paper indicates a basic approach to compare the harmonic impact of current source and voltage source inverters. The latter as a kind of status quo for distributed generation and the first as an uncommon topology in the area of self-commutated infeed. Therefore it is shown how to calculate the fundamental frequency power exchange – what we want. Also the differences in the frequency dependant damping of the inverters higher harmonic output shall be analysed – what we do not want.
Power electronics applied to voltage control in rural distribution networks with penetration of distributed generation
Authors: J. Arrinda  , J. A. Barrena  , M.A. Rodriguez  , S. Malo
Published: May 2017

In rural distribution networks with widely dispersed loads, characterized by the utilization of long overhead lines, voltage profiles with big variations appear along the line due to the significant variations of the load between peak hours and valley hours. This paper describes the problems that the integration of distributed generation based on renewable resources could generate in that scenario, and presents solutions that are commonly used to mitigate these problems and proposes new solutions to solve them. The integration of distributed generation (DG) based on renewable resources in these networks increases the variability of the voltage, and in some cases the power flow of the network also can be bidirectional. Usually this integration of distributed generation is limited by the network operator limiting the maximum voltage variation produced by the distributed generation in the point of common coupling (PCC). In this paper different traditional methods for voltage control are described and analyzed for a widely dispersed rural network scenario. The impact of the DG in these methods of voltage control and the advantages of power electronics in this new scenario are exposed. Power Electronic devices applied to these distribution networks allow more efficient management of the network increasing the integration of distributed generation maintaining the security levels.
Single or dual axis trackers, control systems and electric drive losses for photovoltaic applications
Authors: S. Seme  , G. Štumberger
Published: May 2017

This paper deals with the solar trackers for photovoltaic applications. The solar trackers for photovoltaic system assure that the highest possible share of the available solar radiation reaches the surface of the photovoltaic modules. The electric drive which enables tracking is considered as the loss of the energy produced in the photovoltaic system. The electric power consumption of the photovoltaic tracking system will be written as a function of the angle change.
Analysis of the Energy Quality in a Building Acclimated Through a System of Evaporative Cooling Operated by Frequency Converters.
Authors: Arnulfo Barroso de Vasconcellos  , Douglas Pinto Sampaio Gomes  , Jéssica Romeiro de Carvalho  , Manoel Alexandre de Oliveira  , Teresa Irene Ribeiro de Carvalho Malheiro
Published: May 2017

The present article has as the aim to analyze the level of harmonic distortion of voltage in the bus in an electric system in the presence of evaporative refrigerators used for the cooling of environments operated by converters of frequency in which measurement campaigns were carried out in field. Considering that the frequency converters with the filters absence make the system presents nonlinear characteristics whose analyses are of great matter in what concerns about the quality of the electric energy and the fulfillment of the law and the existing rule, established by the national and international regulating agencies. In this context, through computational simulations, there was observed the efficiency of the passive filters tuned with objective to reduce the levels of harmonic distortions of voltage in the bus in study and to adapt these levels to the standards of reference contained in the existing resolutions. 1
Energy Efficiency and Power Quality in Low Income Consumer Units
Authors: Arnulfo Barroso de Vasconcellos  , Jéssica Romeiro de Carvalho  , Manoel Alexandre de Oliveira  , Douglas Pinto Sampaio Gomes  , Teresa Irene Ribeiro de Carvalho Malheiro
Published: May 2017

The purpose of this paper is to analyze the ex change of incandescent light bulbs by fluorescent ones and old coolers by compact coolers class A Procel Stamped in Consumer Units with low income, who brings besides the increased energy efficiency, positive impact on consumers lives. However, when observing the effects of fluorescent lighting on electric power quality systems where they are applied, there is the appearance of unwanted harmonic distortion on the network. This paper examines the process of replacing the proposed system and veri fies the impact on reducing energy consumption and power quality.
Power Quality versus Electromagnetic Compatibility in Adjustable Speed Drives
Authors: M. I. Buzdugan  , H. Bălan
Published: May 2017

The present approach is intended to bring off a tighter relationship between power quality and electromagnetic interference issues in electric drives. The authors opinion is that if harmonics are widely covered in power quality literature, higher frequency perturbations that inherently appear due to power electronic devices are generally neglected. The concept is developed for adjustable speed drives of wellhead induction motors from a large oil onshore extraction field. Due to the variable loads and the heavy duty cycles of the motors, the harmonics problem needed to be solved in the same time with the conducted electromagnetic perturbations. The harmonic content of the currents together with the conducted electromagnetic interferences were analyzed, mitigation countermeasures being proposed and applied.
Finite Element Analysis of a Three Speed Induction Machine
Authors: L. Melcescu  , T. Tudorache  , M. Popescu
Published: May 2017

This paper deals with the Finite Element (FE) analysis of a special Three Speed Squirrel Cage Induction Machine (TSSCIM) with pole changing stator windings. Compared to classical multi-speed induction machines, the studied TSSCIM is designed so as to change in the same time the number of pole pairs (p) and the number of stator phases (m) so as to keep constant the product p x m. The numerical model of the machine used in this study is based on a 2D plane-parallel finite element approach and aims at finding some of the main steady state operation characteristics of the machine working both as motor and generator for three different running speeds. A comparison of the proposed TSSCIM with a classical inverter fed squirrel cage induction machine is also presented in order to underline some advantages and disadvantages of each solution.
Comparison between Active power filter with selective control and conventional control for harmonic in photovoltaic systems
Authors: J. Osorio  , J. Montaña
Published: May 2017

In order to to improve the power quality from energy generated by the photovoltaic systems connected to the network, this paper presents the results of two types of filters, first the active power filter with conventional control scheme and second, active power filter with a selective control scheme in order to reduce the harmonic content injected by the inverter in a photovoltaic system. The results are presented and compared by means of harmonic distortion (individual and THD). This is a novel proposal, since studies before to this, always have been interested in the compensation of harmonics arising from non linear loads but rarely from a voltage source, as in this case.
New algorithms for estimating the impact of wind turbines on telecommunication services
Authors: I. Cascón  , J. Cañizo  , D. de la Vega  , D. Guerra  , Y. Wu  , A. Arrinda  , I. Fernández  , P. Angueira
Published: May 2017

The estimation of the potential impact of a wind farm on the existing telecommunication services allows the modification of the wind farm layout or the planning of alternative solutions to guarantee the installation of a new wind farm without disturbing the surrounding services. This paper describes the development of new algorithms for the evaluation of the effect of a wind farm on telecommunication services (Air Traffic Control radars, Weather radars, radio links and radio navigation aids), and presents representative examples of impact studies. The novelty of these algorithms is that they estimate the safeguarding areas that should be avoided in the wind farm deployment, and therefore, they can be applied without a previous definition of the wind turbine locations. Therefore, results consist on the set of locations where a wind turbine might interfere in a specific service. These results are represented as visual masks on the terrain, easy to be used on GIS systems or Google Earth, and they are easy to combine with other constraints or datasets used in the wind farm design process (wind data, terrain slope, environmental protected areas, etc.). These algorithms will contribute to simplify and reduce the time required in the wind farm design process.
Health care and social service professionals' perceptions of a home-visit program for young, first-time mothers
Authors: Li S.-A. , Jack S. M. , Gonzalez A. , Duku E. , MacMillan H. L.
Published: May 2017

Introduction

Little is known about health care and social service professionals’ perspective
on the acceptability of long-term home-visit programs serving low-income, first-time
mothers. This study describes the experiences and perspectives of these community care
providers involved with program referrals or service delivery to mothers who participated in
the Nurse–Family Partnership (NFP), a targeted nurse home-visit program.

Methods

The study included two phases. Phase I was a secondary qualitative data analysis
used to analyze a purposeful sample of 24 individual interviews of community care
providers. This was part of a larger case study examining adaptations required to increase
acceptability of the NFP in Hamilton, Ontario, Canada. In Phase II (n ¼ 4), themes
identified from Phase I were further explored through individual, semi-structured interviews
with community health care and social service providers, giving qualitative description.

Results

Overall, the NFP was viewed as addressing an important service gap for firsttime
mothers. Providers suggested that frequent communication between the NFP and
community agencies serving these mothers could help improve the referral process,
avoid service duplication, and streamline the flow of service access. The findings can
help determine key components required to enhance the success of integrating a homevisit
program into an existing network of community services.

Conclusion

The function of home-visit programs should not be viewed in isolation.
Rather, their potential can be maximized when they collaborate and share information
with other agencies to provide better services for first-time mothers.
Composition of Solid Waste in Al Jabal Al Akhdar, a Mountain Region Undergoing Rapid Urbanization in Northern Oman
Authors: Al-Mahrouqi Abdullah I. , Victor Reginald
Published: May 2017

There is a lack of data on the generation and composition of waste in rural areas worldwide. The present study analyzed the composition of solid waste in Al Jabal Al Akhdar, a rural mountain region in the Sultanate of Oman, which is presently experiencing a rapid rate of urbanization due to tourism development. The solid wastes here are generated by the municipality collecting waste from residential, commercial, institutional and recreational areas, the military from a training camp and a few non-governmental private companies from their camps and hotels. The whole load from each of the three sources was manually segregated each month from June 2013 – May 2014. The results indicated that plastic is the dominant category in the wastes collected by the municipality and accounts for 26.7%, followed by paper (17.9%) and then food (14.4%). Food is the dominant category in the wastes collected by the military and private companies and accounts for 36.5% and 45.5% respectively. Management issues associated with solid waste are briefly considered. The study concluded that the municipality should implement an improved system for the collection of plastic waste and initiate a system for recycling it; the military and private companies should reduce the quantities of food waste by improved planning and management of the catering services.
Finite Dimensional Chebyshev Subspaces of Lo
Authors: Kamal Aref K.
Published: May 2017

If A is a subset of the normed linear space X, then A is said to be proximinal in X if for each xÎX there is a point y0ÎA such that the distance between x and A; d(x, A) = inf{||x-y||: yÎA}= ||x­-y0||. The element y0 is called a best approximation for x from A. If for each xÎX, the best approximation for x from A is unique then the subset A is called a Chebyshev subset of X.  In this paper the author studies the existence of finite dimensional Chebyshev subspaces of Lo.
Asociación entre la obesidad abdominal y la prevalencia de factores de riesgo cardiovascular en la ciudad de Cajamarca
Authors: Fuentes Neira Wilmer , Pariona Valer Edith Betzabeth , Segura Vega Luis
Published: May 2017

Objetivo: Determinar la asociación entre la obesidad abdominal y la prevalencia de factores de riesgo cardiovascular en la ciudad de Cajamarca. Materiales y métodos: Estudio descriptivo de corte transversal basado en una submuestra del estudio Tornasol II. La muestra corresponde a los mayores de 18 años de edad encuestados en el área urbana de la ciudad de Cajamarca. La presión arterial fue medida con manómetros de mercurio calibrados y la cintura con cinta métrica exible. Resultados: La prevalencia de la obesidad abdominal según la OMS fue 49 %. Las personas con obesidad abdominal tienen mayor prevalencia de hipertensión (36,3 %) en relación a los no obesos que tienen una prevalencia de hipertensión de 13, 9 % siendo esta diferencias estadísticamente significativa (valor p<0,05), también las prevalencias de hipercolesterolemia se asoció significativamente (valor p<0,05) con la obesidad abdominal. Conclusión: La obesidad abdominal se asocia significativamente con los factores de riesgo como: hipertensión, hipercolesterolemia.
The Development of a Writing Course for Engineers at Vietnam Atomic Energy Institute Using Competence-based Approach
Authors: Duong Mai Thu , Pham Trang Thi Thu
Published: May 2017

Abstract: Strong needs of working learners, urgent demands of the occupation and great expectation of leaders have revealed an immediate call for designing a writing course at Vietnam Atomic Energy Institute (VAEI). At the same time, the use of competence-based approach so that the learning outcomes can meet future staffing requirements of the organization has emerged as advantageous over other approaches of course design. In this case, based on VAEI contexts, learners’ needs and employers’ requirements analysis, the paper is to explore the target genres, determine the specificity of writing competences covered within the course, and then develop a competence-based course schedules. Notably, there have been no attempts in investigating this issue before. Hopefully, the paper would not only present a needed course for engineers at VAEI but also provide suggestions for the course design and implementation in the light of Competence-Based Approach.
“With a Fine-Toothed Comb”: Nicole-Claude Mathieu and the Work of French Feminist Materialist Anthropology
Authors: Cole Sally
Published: May 2017

French anthropologist, Nicole-Claude Mathieu (1937–2014), devoted her career to theorising the institution of marriage; the relations between material conditions and “consent”; and the cross-cultural coexistence of gender diversity and subordination of women. This article traces Mathieu's thinking to her theoretical ties to Claude Lévi-Strauss and Simone de Beauvoir. I read Mathieu's anthropology as part of the long tradition of engaged anthropology and as continuing to offer analytical tools for critical feminist public anthropology. This reading contrasts with views that there are “waves” and opposing “generations” in feminist scholarship.
Street Vending as Ethical Citizenship in Urban Indonesia
Authors: Gibbings Sheri Lynn
Published: May 2017

Street traders in many Indonesian cities face social and legal constraints because they are deemed to be hampering the city's order and cleanliness. I describe how a group of vendors adopted the state's concern over greenery and developed their own “green” project. They also called themselves the rakyat kecil (small people) and argued that they were the poor underdogs being mistreated by the corrupt government. This moral positioning is best seen as an expression of what I am calling “citizenship as ethics,” in which the legitimacy of being in a public space is validated through discourses and actions deemed “good” or “right” in the local public imagination.
Une maison n'est pas seulement un abri ; une maison est aussi un humain
Authors: Chétima Melchisedek
Published: May 2017

L'objectif de cet article est de connecter deux concepts qui ont été déterminants pour le développement des études de la culture matérielle, en particulier dans la déconstruction de l'idée selon laquelle les objets seraient statiques et passifs. Il s'agit de la sémiotique de l'espace et des biographies sociales de l'objet. Si le premier concept a été usité par plusieurs chercheurs africanistes (Griaule, Blier, Malaquais, etc.), le second n'a pas encore fait l'objet d'une théorisation mis à part les travaux de l'anthropologue allemand Hans Peter Hahn. Dans ce travail, la mise en relation de la sémiotique de l'espace et la méthode biographique permet d'étudier le rapport réciproque entre individus et maisons dans les Monts Mandara du Cameroun, rapport dans lequel les individus construisent les maisons en même temps qu'ils sont construits par elles.
How Do You Like Me Now?: Exploring Subjectivities and Home/Field Boundaries in Research with Women in Sex Work
Authors: Dewey Susan , Orchard Treena
Published: May 2017

Anthropological analyses of blurred researcher–participant relationships and fieldwork boundaries in settings that double as the field and the researcher's home typically focus on the anthropologist's experiences, to the exclusion of how participants construct their own subjectivities in these fluid field sites. Using ethnographic vignettes from our research with women in sex work conducted in the neighbourhoods and services provision sites where we live and work, this article introduces the concept of “subjectivity work” as a means of exploring how we, alongside our participants, reconfigured our relationships to each other and the shifting boundaries of the field.
Mirabel : Au nom du développement
Authors: Poulin Éric Gagnon
Published: May 2017

En 1969, le gouvernement de Pierre Elliott-Trudeau réalisa la plus grande expropriation de l'histoire du pays au nom du développement, afin de construire le plus grand aéroport au monde : Mirabel. Le projet fut un cuisant échec pour plusieurs raisons sociales, politiques et économiques. Cet article se concentre essentiellement sur le discours du développement entourant le projet véhiculé par l'État, le rapport à la propriété privée et sur la lente mobilisation politique des expropriés de Mirabel.
Une anthropologie amphibienne : La production du lieu à la confluence du territoire/de la terre et de l'eau
Authors: Gagné Karine , Rasmussen Mattias Borg
Published: May 2017

Parmi les changements climatiques et les inégalités de l'économie politique mondiale tirant profit de l'exploitation des ressources naturelles, les paysages formés à la confluence de la terre et de l'eau se redéfinissent à la fois de manière abstraite et concrète. En considérant plus précisément la production des lieux, nous suggérons qu'à leur point de convergence se trouve une relation ontologique entre l'eau et la terre. Cette relationalité constitue ce que nous définissons comme une anthropologie amphibienne. En mettant de l'avant la temporalité, le mouvement ainsi que différentes façons, de connaître ou de comprendre, nous tentons de saisir l'expérience plurielle des lieux à la confluence de la terre et de l'eau, et d'y examiner les spécificités de la vie et de l'anthropologie amphibienne.
Getting Started with Peer-Assisted Learning in a Veterinary Curriculum
Authors: Bell Catriona E. , Rhind Susan M. , Stansbie Nigel H. , Hudson Neil P.H.
Published: May 2017

Peer-Assisted Learning (PAL) methodologies that involve students teaching other students have been shown to be valid and effective in a variety of disciplines and are gaining increasing interest within veterinary medical education. PAL has been formally embedded within the undergraduate veterinary clinical skills curriculum at the Royal (Dick) School of Veterinary Studies (R(D)SVS), Edinburgh, since 2009 (and informally for several years before this) and has been delivered successfully to over one thousand first-year tutees by over one thousand fourth-year tutors (in their penultimate clinical year). This “teaching tip” article therefore aims to provide an informative overview of PAL for colleagues who may be interested in the methodology and to give practical tips as to how it can be successfully implemented in a veterinary degree program. We will summarize key evidence from the literature, provide a detailed example of how PAL has been implemented and optimized in our own veterinary degree program, include a subset of representative evaluation data from both tutors and tutees, and then conclude by providing colleagues with practical tips and resources (such as planning checklists and lesson plan templates) for implementing a PAL activity at their own school.
Radiodensity of intraventricular hemorrhage associated with aneurysmal subarachnoid hemorrhage may be a negative predictor of outcome
Authors: Nguyen Ha Son , Li Luyuan , Patel Mohit , Kurpad Shekar , Mueller Wade
Published: May 2017

OBJECTIVE

The presence, extent, and distribution of intraventricular hemorrhage (IVH) have been associated with negative outcomes in aneurysmal subarachnoid hemorrhage (SAH). Several qualitative scores (Fisher grade, LeRoux score, and Graeb score) have been established for evaluating SAH and IVH. However, no study has assessed the radiodensity within the ventricular system in aneurysmal SAH patients with IVH. Prior studies have suggested that hemorrhage with a higher radiodensity, as measured by CT Hounsfield units, can cause more irritation to brain parenchyma. Therefore, the authors set out to investigate the relationship between the overall radiodensity of the ventricular system in aneurysmal SAH patients with IVH and their clinical outcome scores.

METHODS

The authors reviewed the records of 101 patients who were admitted to their institution with aneurysmal SAH and IVH between January 2011 and July 2015. The following data were collected: age, sex, Glasgow Coma Scale (GCS) score, Hunt and Hess grade, extent of SAH (none, thin, or thick/localized), aneurysm location, and Glasgow Outcome Scale (GOS) score. To evaluate the ventricular radiodensity, the initial head CT scan was loaded into OsiriX MD. The ventricular system was manually selected as the region of interest (ROI) through all pertinent axial slices. After this, an averaged ventricular radiodensity was calculated from the ROI by the software. GOS scores were dichotomized as 1–3 and 4–5 subgroups for analysis.

RESULTS

On univariate analysis, younger age, higher GCS score, lower Hunt and Hess grade, and lower ventricular radiodensity significantly correlated with better GOS scores (all p < 0.05). Subsequent multivariate analysis yielded age (OR 0.936, 95% CI 0.895–0.979), GCS score (OR 3.422, 95% CI 1.9–6.164), and ventricular density (OR 0.937, 95% CI 0.878–0.999) as significant independent predictors (p < 0.05). A receiver operating characteristic curve yielded 12.7 HU (area under the curve 0.625, p = 0.032, sensitivity = 0.591, specificity = 0.596) as threshold between GOS scores of 1–3 and 4–5.

CONCLUSIONS

This study suggests that the ventricular radiodensity in aneurysmal SAH patients with IVH, along with GCS score and age, may serve as a predictor of clinical outcome.