bluuebunny/crossref_metadata_2025 huggingface dataset:
Power-Flow-Optimising-Algorithm used in an Energy Management for Micro Grids
Authors: J. Teuscher  , B. Born  , W. Schufft
Published: May 2017

This paper contains an overview about a power flow-optimising-algorithm and the usage in an energy management for smart low-voltage grids (micro grids). This algorithm is based on a clustering of a number of households to reduce the distance between consumers and suppliers and so to reduce the transport losses in low-voltage grids. Such a power flow optimising enables to accomplish the requirements on low voltage grids (f.e. a high number of photovoltaic systems or electric vehicles). Furthermore, the paper contends the usage of this algorithm in an energy management system and the results of some first calculations.
Object-Oriented Modelling of Small Hydropower Plants
Authors: M. L. Ruz  , J. Garrido  , S. Fragoso  , F.Vázquez
Published: May 2017

The improvement of the exploitation of energy resources in power stations is a topic of growing interest. However, experimentation costs in order to increase productivity are very high, either because the possible equipment to change would be very expensive, or simply, because the plant would have to stop. In such cases, the simulation is a fast and cheap way to analyze the power plant behavior in order to try to improve its performance by means of modifying the control strategy or changing some elements of the plant. This work is focused on small hydropower plants and it presents the design of a library for modelling these power stations. After reviewing the desirable features of simulation, an approach based on an object oriented modelling language is used. This approach allows the different elements of the plant (dam, gates, turbines, tubes, generators...) to be created and validated individually, and facilitates their interconnections in order to set up easily and quickly models of different stations. By simulating these models, it is possible to obtain interesting information, like reservoir level, flows, pressures, head losses in any component, turbine efficiencies and so on. The modelling of two real hydropower plants installed in Córdoba is presented.
Analytical Expression For The Tower Height of WECS
Authors: Sobhy Mohamed Abdelkader
Published: May 2017

This paper presents an analytical expression for the optimum tower height of a wind turbine in a given site. The optimum tower height is determined such that to maximize the probability of the effective wind speed range and hence keeping the wind turbine generator working the longest possible time period in that range. A chart is also presented for graphical determination of the optimum tower height. The optimum tower height determined helps as an indicator for wind turbine-site matching; very large values, beyond the practical limits, means that the wind turbine generator characteristics do not match the wind resource at the site.
Study of parameters for the design of a continuous flow laboratory biogas reactor
Authors: C. A. Almeida  , A. J. Alves  , S. B. Oliveira  , J. W. Zang  , W. P. Calixto  , E. G. Domingues
Published: May 2017

This study aimed to determine the parameters needed to design a continuos flow bioreactor. Developing studies that expand the quantity and efficiency of biogas currently produced on an industrial anaerobic wastewater treatment in a food processing plant in the Brazilian State of Goiás. The procedures developed in this work we used nine sets of bioreactors in batch and followed the German Standard VDI 4630. A special workbench was developed for that purpose, alternative procedures for determining the volume of the produced biogas were tested. The biomass studied in this work is the resulting sludge of the wastewater treatment from an industrial plant. The daily production is about nine tons, currently, which is totally discarded. Through this batch tests, it was possible to calculate the volume of biogas production and the ideal biomass retention time of the biomass. Obtained data to project a laboratory continuous flow bioreactor. With this data was made a projection of the biogas production potential by the use of this feedstock in an industrial bioreactor constructed for this purpose.
Control strategy for an interface to improve the power quality at the connection of AC microgrids
Authors: Salvador P. Litrán  , Patricio Salmerón  , Jaime Prieto  , Alejandro Pérez
Published: May 2017

In this paper, a control strategy is proposed for an interface which is connected between a microgrid and main grid. The interface is based on an active power filter configuration of series connection. The proposed control strategy allows mitigating of current harmonics and reduction of voltage unbalances that may appear at the microgrid side and/or at the network side. The proposed strategy was verified by simulation. To do this, a simulation platform based on MATLAB-Simulink was developed. The interface was subjected to voltage unbalances and current harmonics produced at the microgrid side and main grid side. The results obtained demonstrate the validity of the designed interface with the proposed strategy.
Employing Hydrogen Fuel Cell in Hybrid Energy Systems for Stand-Alone, Off Grid Remote Sites in UAE
Authors: Ensiyeh Keshtkaran  , Abbas A. Fardoun  , Hassan Noura
Published: May 2017

In this paper, the economic feasibility of Proton Exchange Membrane Fuel Cell (PEMFC) as part of a stand alone renewable energy system for a remote application in UAE is examined and investigated. HOMER (computer software simulation tool) was used to conduct the analysis for sizing and optimization. The study takes into account the load requirement variations, capital cost (FC, PV and diesel generator cost) and running cost (Hydrogen, PV cleaning, and diesel cost). The costs are based on the location of interest. In addition, equivalent circuit model of the fuel cell system is developed based on experimental data. Simulated results matches the experimental data very well at steady state conditions.
Comparison of Discharge Performance of 12V/150Ah Gel and AGM Sealed Lead acid Batteries in Stand-alone PV-based Systems in UAE
Authors: Zahi M. Omer  , Ahmed M. Alameri  , Abbas A. Fardoun  , Ala A. Hussein
Published: May 2017

This paper investigates the discharge performance of two major lead-acid batteries, namely 12V/150Ah Gel and AGM sealed lead-acid batteries, when operating in stand-alone (off grid) mode in photovoltaic (PV) based systems in United Arab Emirates (UAE). At harsh environmental conditions such as in UAE where the temperature can go to extremely high level in the summer, the battery performance and replacement cost increases the concerns about the reliability and economic feasibility of those batteries. This paper compares the discharge characteristics of those batteries through discharge tests performed on four similar batteries (two of each type). Experimental results of the discharge tests followed by a comparison between the two batteries are presented in this paper.
Assessment of unbalance and distortion in power systems that include active power line conditioners.
Authors: Jaime Prieto  , Patricio Salmerón  , Alejandro Pérez  , Salvador P. Litrán
Published: May 2017

This paper presents a decomposition of the apparent power of a system that allows to separate the contribution to the unbalance of the whole set of harmonics of voltages and currents. From this set of power terms, the unbalanced fundamental, balanced harmonics and unbalanced harmonic indices are derived, that allow to evaluate separately the distortion and the unbalance. This procedure gives a more appropriate way to characterize the mitigation obtained using modern equipments with active compensation. These new indicators of the electric power quality have been applied here to a system with unbalance and distortion in the supply and the load, before and after the connection of a parallel active compensator, and with the connection of a series-parallel active compensator. The results obtained with a dedicated experimental platform have allowed to verify the validity of the new proposed indices.
Electric motors monitoring: An alternative to increase the efficiency of ball mills
Authors: M. G. Melero  , J. M. Cano  , J. Norniella  , F. Pedrayes  , M. F. Cabanas  , C. H. Rojas  , G. Alonso  , J. M. Aguado  , P. Ardura1
Published: May 2017

Ball mills can be frequently found in ore grinding facilities. These machines show high energy consumption together with a low efficiency. As a consequence, even a small improvement on the performance of the grinding process can have a huge impact in the operating costs of the plant and in the optimization of energy resources. One of the reasons for this low efficiency rate is the difficulty of identifying the filing level, and as a consequence, the difficulty of operating the mill at the optimum filing condition. Through an extensive bibliographic review, this work attempts to reveal the interesting possibilities that motor monitoring techniques can have in improving the efficiency of ball mills
An Overview on the Portuguese Quality of Electricity Supply Code Revision 2013: The Continuity of Supply and Power Quality Perspective
Authors: S. Faias  , R. Castro  , J. Esteves
Published: May 2017

New legislation, published in September and October 2012, transferred to the Portuguese national regulatory authority for energy services (ERSE) the authority to prepare and approve the national regulatory code on the quality of electricity supply. As a consequence, ERSE promoted a revision of the quality of supply code, which came in force in January 2014. This paper presents an overview on the Portuguese quality of electricity supply code revision, highlighting the main topics addressed during this revision, in what concerns continuity of supply and voltage quality aspects. The quality of electricity supply code revision created an opportunity to adjust the quality of supply requirements to the current networks performances, to promote a change on the continuity of supply performance analysis, from a network operators perspective to a customers perspective, and to increase the share of responsibilities between network operators and users.
Partially shaded photovoltaic panel
Authors: T. Fekonja  , K. Deželak  , G. Štumberger
Published: May 2017

This paper deals with a model of partially shaded photovoltaic module. It is build as an electric circuit consisting of individual solar cells and bypass diodes. The parameters and operating points of individual solar cells change depending on the solar cell temperature and the level of solar irradiance. The output characteristics of the photovoltaic module model are determined numerically by finding solutions for the given electrical circuit, considering solar irradiance on the surface of each individual solar cell. The proposed model can provide realistic behaviour of partially shaded photovoltaic module required in simulation tools used in the development of a micro inverter. The model was confirmed by measurements performed on the tested photovoltaic module.
Analysis, Modeling, and Control of an AC Microgrid System Based on Green Energy
Authors: M.F. Elsied  , A. Oukaour  , H. Gualous  , Y. Slamani  , R.Hassan  , A.Amin
Published: May 2017

The integration of distributed generators (DGs), electric storage system (ESS), distributed electric loads and the utility grid through the point of common coupling is called microgrid (MG) .The coordinated operation of MG and the main utility grid with variable load demand is controlled by using microgrid control center (MGCC). MGCC methodology is introduced to regulate power flow for each source depends on the outputs commands from MG energy management center (MGEMC). This paper is focused only on developing an efficient and fast MGCC based on power control mode taking into account the outputs commands from MGEMC without considering its strategy. The MG in this paper is assumed to be interconnected to the main utility gird, and can purchase some power from utility grid at off-peak hours or when the production of the MG is insufficient to meet the load demand. On the other hand, there is a daily income to the MG when the generated power exceeds the load demand during on-peak hours. The proposed MGCC and electrical power system is simulated using Matlab/Simulink.
An analysis of the characteristics of the simultaneous feed-in of photovoltaic and wind power plants based on measured power values
Authors: A. Göhlich  , W. Schufft
Published: May 2017

This paper shows the results of the analysis of the measured power values of photovoltaic and wind power plants in the proximity of several electrical substations. The aim is to receive an impression of the frequency, time and duration of very low and very high simultaneous feed-ins of photovoltaic and wind power plants. Therefore, the data of nine electrical substations is analysed. Besides typical statistical values, a comprehensive analysis on the occurrence, extent, distribution, time and duration of the totalized photovoltaic and wind power feed-in is made. The results show that the occurrence of extreme totalized photovoltaic and wind power feed-in basically depends on the relation r of the installed nominal power of both plant types. For an optimal relation r, there are only a few or even almost no very high feed-ins and the number of very small feed-ins can be reduced by balancing the relation r to about 0.5.
Implementation of a Forest Biomass-based Biofuel Industry: A Canadian Experience
Authors: Mariya Marinova  , Michel Perrier  , Jean Paris
Published: May 2017

The forest biomass is an abundant renewable resource from which biofuels can be derived. In the Kraft process the cellulose is extracted from the wood to form the paper pulp while the other organic components, primarily hemicelluloses and lignin, are burnt to produce steam. It is possible to divert part of the hemicelluloses or lignin to produce fuels on site, a mode of operation referred to as the integrated forest biorefinery. Hemicelluloses can be hydrolysed into sugars which in turn are converted into ethanol or butanol while lignin can be extracted from a residual process stream, the black liquor, by acid precipitation, de-ionized, dried and directly used as a fuel or further processed into value added chemicals. Biorefinery processes have been proposed and analysed by simulation on ASPEN PLUS. Intensive integration of thermal energy, water and material systems is of paramount importance to the sustainability of the global site; the increased energy load on the utility systems could cause rising dependency of the global site on fossil fuels. To avoid this consequence, a new original energy efficiency analysis an enhancement methodology has been developed and validated on actual Canadian Kraft mills before being applied to the integrated biorefinery and has produced remarkable results far superior to the current engineering practice. This has led to the concept of the green integrated forest biorefinery (GIFBR). i.e. an industrial site with zero fossil fuel consumption and reduced GHG emissions vs. the Kraft process and biorefinery plant alone. The GIFBR incorporates a woody biomass gasifier producing syngas as a fuel for the integrated biorefinery and for steam production or sale. It can also include a combined heat and power (CHP) unit driven by steam made available by liberated production capacity from the installed power plant.
Complex method for performance prediction of photovoltaic systems
Authors: M. J. Mayer  , A. Dán
Published: May 2017

This paper shows a method for modelling photovoltaic (PV) systems, including different models for the solar cells, DC circuit and the inverter. The author created a Matlab simulation based on these models, enabling to perform various calculations. Predicting the amount of energy produced by PV systems has a great impact on the accurate calculation of financial return of investment. Furthermore the more accurate estimation of produced energy promotes the system integration of small-scale PV generators by enabling to schedule their production. The different analyses shown in this paper helps to understand the operation characteristics and the most important design considerations of these small-scale solar plants.
Impact of Plug-In Electric Vehicle Battery Charging on a Distribution System Based on Real-Time Digital Simulator
Authors: A. Alharbi  , A. Eltom  , N. Sisworahardjo
Published: May 2017

Although the electric vehicles (EVs) have many economic and environmental advantages as compared to the conventional cars, the increased adoption of these vehicles will bring up new concerns for the power distribution grid in terms of introducing new peaks into the system or causing voltage quality problems. This study investigates the impact of the electric vehicles battery charging on the distribution system in terms of voltage unbalance at various locations, transformers overloading, and shifting the peak of the system. In this research, a 12.47 kV real distribution network has been modelled using real time digital simulator, using real data from a power distributor. The study presents four different scenarios of uncoordinated EVs integration for two different charging times (evening and night) and two different charging rates (level I and level II) at different penetration levels ranging from 10% to 100%. Voltage unbalance at different locations is determined and transformer overloading is analysed. The influence of EVs charging on the daily load curve is shown.
Study of the distribution of temperatures in the windings of a transformer after suffering a short-circuit.
Authors: I. Fernández  , J. Carcedo  , F. Ortiz  , F. Delgado  , A. Ortiz  , A. Arroyo
Published: May 2017

Power transformers are electrical machines that allow us to transport electric energy, with reduced losses, from generation stations to consumption points. This definition gives us an idea of the number of machines of this type that are used in power distribution systems worldwide. The lifespan of this equipment often exceeds 30 years of operation. Therefore, they can be described as very robust equipment. The main problem that may affect power transformers is the operation at high temperature. This paper summarizes the results of a post mortem study carried out on an 800 kVA distribution transformer. The methodology that is considered for estimating the temperature distribution in the windings of the machine is based on the calculation of the degree of polymerization of the dielectric paper. This parameter is associated with the state of the paper insulation that protects the conductors of the windings. By knowing the value of this magnitude for a new and for an aged paper, and the period of operation of a transformer, the temperature distribution along the height of the windings can be estimated. With these results and the loading regime that a transformer has endured throughout his life, one can draw conclusions for future designs or for similar transformers still in operation.
Video-assisted extirpation of cranial mediastinal masses in dogs: 18 cases (2009–2014)
Authors: MacIver Melissa A. , Case J. Brad , Monnet Eric L. , Hunt Geraldine B. , Mayhew Philipp D. , Oblak Michelle L. , Runge Jeffrey J. , Singh Ameet , Smeak Daniel D. , Steffey Michele A. , Boston Sarah E.
Published: May 2017

OBJECTIVE To characterize clinical findings, surgical procedures, complications, and outcomes in dogs undergoing extirpation of masses from the cranial mediastinum via video-assisted thoracic surgery (VATS) and establish preliminary guidelines for case selection when considering VATS for thymectomy in dogs.

DESIGN Retrospective case series.

ANIMALS 18 client-owned dogs that underwent extirpation of a cranial mediastinal mass by means of VATS at 5 academic referral hospitals from 2009 through 2014.

PROCEDURES Medical records were reviewed and data extracted regarding signalment, clinical signs, physical examination findings, diagnostic imaging results, surgical approach and duration, cytologic and histologic examination results, complications, outcome, and cause of death, when applicable.

RESULTS 16 dogs had a thymoma, 1 had thymic anaplastic carcinoma, and 1 had hemangiosarcoma. Seven had both megaesophagus and myasthenia gravis. Median approximate tumor volume was 113.1 cm3 (interquartile range, 33.5 to 313.3 cm3). Median duration of VATS was 117.5 minutes (interquartile range, 91.5 to 136.3 minutes). Conversion to an open thoracic surgical procedure was required for 2 dogs, 1 of which died during surgery. Median survival time following VATS for dogs with thymoma and concurrent myasthenia gravis and megaesophagus was 20 days. Dogs with thymoma without paraneoplastic syndrome survived for ≥ 60 days, and none of these dogs died of disease-related causes.

CONCLUSIONS AND CLINICAL RELEVANCE VATS appeared to be an acceptable approach for extirpation of masses from the cranial mediastinum in dogs under certain conditions. Dogs with myasthenia gravis and megaesophagus had a poor postoperative outcome.
Sintesis Oksida Aurivillius Sr2Bi4Ti5-xFexO18 (x = 0,25; 0,5; 0,75; dan 1)
Authors: Rusli Rolan , Ismunandar Ismunandar
Published: May 2017

Aurivillius oxides Sr2Bi4Ti5-xFexO18 have been synthesized using the solid state reaction method. Powder X-ray diffraction data were refined using Le Bail method implemented in Rietica have space group B2cb, Z = 4, and parameter cell are a = 5.542(8), b = 5.474(9), c = 48.947(1); a = 5.565(5), b = 5.491(9), c = 49,097(1); a = 5.533(7), b = 5.464(7), c = 48.595(2) and a = 5.621(1), b = 5.492(9), c = 49.78(4); respectively for x = 0.25, 0.5, 0.75, and 1. The substitution of cation Fe3+ in these Aurivillius oxides was showed increasing of magnetic moment are Î¼ = 2.67, 3.21, 3.98, and 4.62 for x = 0.25, 0.5, 0.75, and 1 respectively.
Keywords: Aurivillus oxide, solid state reaction, Le Bail method, magnetic moment
ABSTRAK
Oksida Aurivillius Sr2Bi4Ti5-xFexO18 telah disintesis dengan menggunakan metode reaksi kimia padat. Data difraksi sinar-x serbuk yang penghalusan strukturnya menggunakan metode rietveld dengan program rietica menunjukkan bahwa oksida ini memiliki grup ruang B2cb, Z = 4, dan parameter selnya adalah a = 5,542(8), b = 5,474(9), c = 48,947(1); a = 5,565(5), b = 5,491(9), c = 49,097(1); a = 5,533(7), b = 5,464(7), c = 48,595(2) dan a = 5,621(1), b = 5,492(9), c = 49,78(4); berturut-turut untuk x = 0.25; 0,5; 0,75; dan 1. Substitusi kation Fe3+ pada oksida Aurivillius ini menunjukkan terjadinya peningkatan momen magnet oksida ini yaitu Î¼ = 2,67; 3,21; 3,98; dan 4,62 berturut-turut untuk x = 0,25; 0,5; 0,75; dan 1.
Kata kunci: Oksida Aurivillius, reaksi kimia padat, metode Le Bail, momen magnet
Aktivitas Hepatoprotektor Batang Fibraure tinctoria Lour Secara In Vivo
Authors: Fikriah Ika
Published: May 2017

Study on Fibraurea tinctoria Lour (FT) stems gives information about its traditional utility as  yellow fever treatment. Research of antecedent of FT stem proved that inhibited lipid peroxidation more effective than tocopherol acetate. These study was intended to prove hepatoprotector activity of ethanolic FT stem extract by in vivo. FT stem extract was macerated using absolute ethanol during 5 days that was repeated  3 times . FT stem extract hepatoprotector activity by in vivo was tested using carbon tetrachloride induced hepatotoxicity on Wistar rat. They were given FT stem extract orally once a day at dose 50, 100, and 200 mg/kgBW and Curcumin at dose 50 mg/KgBW as positive control.  After 10 days, all groups were examined liver function (SGOT, SGPT, ALP), liver Malonedialdehide (MDA) level by Thiobarbituric acid method,  and liver histopathology by Haemotoxylin-Eosin staining. Group that induced by CCl4 showed significant elevation of SGOT, SGPT and ALT also Liver MDA than group control. FT stem extract treatment inhibited elevation of SGOT, SGPT, ALT and Liver MDA significantly.Qualitative histopathological examination on Group 2 showed extensive fibrosis and necrosis, along with  periportal PMN and lymphocyte infiltration. FT stem extract treatment inhibited pathological change that was induced by CCl4. Dose elevation showed tendency of stronger inhibition on liver cell tissue destruction and inflammation.

Key words: Fibraurea tinctoria, hepatoprotector, in vivo

 

Abstrak

Penelusuran secara etnobotani, batang Fibraurea tinctoria Lour (FT) digunakan untuk obat sakit kuning. Penelitian pendahuluan batang FT berkemampuan meredam peningkatan lipid peroksidasi secara in vitro yang lebih kuat dibandingkan dengan tokoferol asetat. Membuktikan khasiat ekstrak etanol batang FT sebagai hepatoprotektor secara in vivo. Batang FT dimaserasi dengan etanol absolut selama 3 x 5 hari. Uji hambatan kerusakan hati secara in vivo digunakan model tikus yang diinduksi karbon tetraklorida (CCL4), ekstrak etanol FT diberikan dengan dosis 50, 100, 200 mg/KgBB sekali sehari dan curcumin dosis 50 mg/KgBB sebagai kontrol positif selama 10 hari lalu diperiksa fungsi hati (serum SGOT, SGPT dan ALP), kadar malondialdehida hati (MDA-hati), serta pemeriksaan patologi anatomi hati dengan pewarnaan Hematoksilin Eosin (HE). Kelompok tikus yang diinduksi CCl4 memperlihatkan peningkatan nilai SGOT, SGPT dan ALT dan MDA-Hati secara bermakna dibandingkan dengan kontrol. Pemberian ekstrak etanol batang FT secara oral dapat melemahkan peningkatkan nilai SGOT, SGPT dan ALT serta dapat menghambat peningkatkan nilai MDA-Hati pada tikus yang diinduksi CCl4 secara bermakna. Hasil pemeriksaan PA menunjukkan fibrosis dan nekrosis yang luas disertai infiltrasi sel-sel PMN dan limfosit di daerah periportal pada kelompok tikus yang diinduksi CCl4 > Curcumin > FT 50 > FT 100 > FT 200 mg/KgBB.

Kata Kunci: Fibraurea tinctoria, Hepatoprotektor, in vivo
Beberapa Tumbuhan Obat Asal Kalimantan Timur sebagai Sumber Saponin Potensial
Authors: Rijai Laode
Published: May 2017

Saponin is a class of natural compounds that have activity that is strongly associated with utilization in pharmacy. Exploration has been carried out against a number of secondary metabolite content of medicinal plants in East Kalimantan and some of them found to contain saponins. Plants were found to contain saponins and are considered potential Kokang leaf (Lepisanthes amoena), Kesumbakeling leaf (Bixa orellana, L), Belimbing Wuluh leaf (Averrhoa bilimbi L.), Sugi Gadjah leaf (Hyptis capitata), Karamunting leaf (Melastoma malabathricum L), Cempedak bark (Artocarpus champeden), Wijaya Kusuma leaf (Epiphyllum oxipetalum), Langsat seeds (Lansium domesticum), ekor kucing leaf (Acalypha hispida), Kelor bark (Moringa oleifera), Jarong leaf (Stachytarpheta mutabilis), Miana leaf (Coleus atropureus), Jengger Ayam leaf (Celosia cristata), and fruit of Libo (Ficus vargelata).
Key words : East borneo medicinal plants, saponins
 
Abstrak
Saponin adalah golongan senyawa alami yang memiliki aktivitas yang sangat terkait dengan pemanfaatan dalam bidang farmasi. Telah dilakukan eksplorasi kandungan metabolit sekunder  terhadap sejumlah tumbuhan obat yang ada di Kalimantan Timur dan beberapa diantaranya terbukti mengandung saponin. Tumbuhan-tumbuhan yang terbukti mengandung sponin dan dianggap potensial adalah daun Kokang (Lepisanthes amoena), daun Kesumbakeling (Bixa orellana, L), daun Belimbing Wuluh (Averrhoa bilimbi L.), daun Sugi Gadjah (Hyptis capitata), daun Karamunting (Melastoma malabathricum L), kulit batang Cempedak (Artocarpus champeden), daun Wijaya Kusuma (Epiphyllum oxipetalum), biji Langsat (Lansium domesticum), daun ekor kucing (Acalypha hispida), Kulit Batang Kelor (Moringa oleifera), daun Jarong (Stachytarpheta mutabilis), daun Miana (Coleus atropureus), daun Jengger Ayam (Celosia cristata), buah Libo (Ficus vargelata).
Kata Kunci: Tumbuhan Obat Kaltim; Saponin
INTERAGINDO PLANTAS MEDICINAIS E CORPO HUMANO NO ENSINO FUNDAMENTAL
Authors: Leal Kelly Mauricio , Ayres Ana Cléa Braga Moreira , Santos Marcelo Guerra
Published: May 2017

Esta pesquisa constituiu-se no levantamento das ideias dos alunos do 8º ano do Ensino Fundamental de uma escola pública do estado do Rio de Janeiro (Brasil), sobre a utilização das plantas medicinais e no desenvolvimento de estratégias que propiciassem a interação deste tema com o estudo do corpo humano. A metodologia utilizada compreendeu cinco etapas, a saber: relativa ao uso e propriedades das plantas medicinais; diagnóstico sócio cultural; sintomas das doenças. Nas três primeiras etapas os questionários funcionaram como instrumento fundamental na obtenção de dados e foram dirigidos aos alunos e seus familiares. A quarta etapa permitiu: coleta e a identificação das plantas medicinais pelos alunos e a quinta etapa a realização de um jogo em sala de aula. Foi possível observar, por meio destas atividades, que o conhecimento sobre as propriedades terapêuticas das plantas diminuía à medida que aumentava o nível de escolarização. Com relação às ideias dos alunos sobre a utilização/reconhecimento das plantas e aspectos vinculados à saúde, os resultados obtidos coincidiram em mais da metade dos casos com a literatura consultada, mostrando o quão importante é a valorização do saber popular pela escola. O resgate do saber popular no que se refere ao uso das plantas medicinais proporcionou alternativas que atuaram como facilitadoras da aprendizagem dos alunos.
SEQUÊNCIA DIDÁTICA PARA O ENSINO-APRENDIZAGEM DA TEMÁTICA DO ABORTO NO ENSINO FUNDAMENTAL
Authors: Machado Elaine Ferreira , Miquelin Awdry Feisser
Published: May 2017

Este artigo analisa uma proposta de sequência didática para a abordagem da temática do aborto, nas séries finais do Ensino Fundamental, considerando a fragilidade das informações veiculadas pelos livros didáticos de Ciências. Objetivando superar essa fragilidade em temática tão relevante, a sequência foi elaborada e desenvolvida com oitavos anos do Ensino Fundamental, em uma escola pública do Paraná. Como resultados, verificou-se que, investigar o tema com os estudantes, através do diálogo-problematizador e, desenvolver atividades metodológicas baseadas nesses princípios freirianos, trazem boas expectativas de uma educação para a emancipação.
AS INTERFACES ENTRE O ENSINO DE CIÊNCIAS E A PSICOLOGIA DO DESENVOLVIMENTO: A CONTRIBUIÇÃO DE VIGOTSKI
Authors: De Oliveira Luiza Rodrigues , Sbano Valmir , Latini Rose Mary
Published: May 2017

Este artigo discute interface entre o Ensino de Ciências e um de seus fundamentos, a Psicologia do Desenvolvimento. De forma geral, o conceito de desenvolvimento humano vem sendo apresentado como processo de estruturação psicológica da infância até a fase adulta, definição que remete à psicologia produzida a partir do modelo da sociedade moderna, que acentua a concepção de natureza humana individual e universal. Uma abordagem do Ensino de Ciências está associada a este modelo, que valoriza a investigação sobre os mecanismos universais do funcionamento psicológico no processo de construção de conhecimento, produzindo práticas educativas que negam as diferenças entre os sujeitos no processo de desenvolvimento. E, além disso, produzindo  um panorama da aprendizagem científica que propõe que no desenvolvimento intelectual da criança não há interação entre os conceitos espontâneos e os conceitos científicos, mas antes uma fronteira, entre as idéias criadas por um desenvolvimento mental prévio à realidade, oriundo das operações psicológicas universais, e as concepções científicas. Estudamos o desenvolvimento psicológico a partir de outra vertente teórica acerca dos vínculos entre o cultural e o universal, a abordagem histórico-cultural. A psicologia de Vigotski descreve o desenvolvimento como um processo que acontece na inserção do homem na cultura, o que leva a compreensão da subjetividade como sendo a produção da singularidade ao longo da história coletiva. Esta ênfase epistemológica engendra novo modo de entender a formação das funções psicológicas superiores e, consequentemente, a formação dos conceitos, prevendo uma relação dialética entre os conceitos espontâneos e os conceitos científicos.
Development of congestion in compressible flow with singular pressure
Authors: Bresch Didier , Renardy Michael
Published: May 2017

This short note concerns the formal limit presented in [ J. Comput Phys 230 (2011), 8057–8088] and [ Actes colloquia Rouen (2012)] between the compressible Euler equations with singular pressure (soft model) and the pressureless Euler system with unilateral constraint (hard model). These soft and hard models with maximal constraint on the density are used to reproduce congestion phenomena. In this paper, we are interested in the question how the different regions (congested and non-congested regions) fit together and how the transition occurs when congestion first develops in the initial system namely the compressible Euler equation with singular pressure. We shall develop a formal solution by matched asymptotics and show that a shock front may separate the congested region from the outside non-congested region. This, in some sense, shows that to justify the formal limit between the two models (soft and hard Euler systems), the shock fronts formation has to be considered and mathematically analyzed.
Sintering of Two Viscoelastic Particles: A Computational Approach
Authors: Balemans Caroline , Hulsen Martien , Anderson Patrick
Published: May 2017

Selective laser sintering (SLS) is a high-resolution additive manufacturing fabrication technique. To fully understand the process, we developed a computational model, using the finite element method, to solve the flow problem of sintering two viscoelastic particles. The flow is assumed to be isothermal and the particles to be in a liquid state, where their rheology is described using the Giesekus and XPP constitutive models. In this work, we assess the parameters that define this problem, such as the initial geometry, the Deborah number and other dimensionless parameters present in the rheological models. In particular, the conformation tensor is considered, which is a measure for the polymeric strain and plays an important role in the crystallization kinetics of semicrystalline polymers like polyamide 12, usually used in SLS.
Fire Damage Assessment of Reinforced Concrete Structures Using Fuzzy Theory
Authors: Cho Hae-Chang , Lee Deuck , Ju Hyunjin , Park Hyun-Cheol , Kim Heung-Youl , Kim Kang
Published: May 2017

Once a reinforced concrete (RC) structure is damaged by fire, the fire damage assessment should proceed to take appropriate post-fire actions, including the decision-making of whether it can be repaired for reuse or not. Since the assessment results of current fire damage diagnosis methods, however, highly depend on the subjective judgment of inspectors, it is hard to ensure their objectiveness and reliability. This study, therefore, aims to develop a new fire damage diagnosis system (FDDS) based on fuzzy theory that can provide objective and comprehensive evaluation results by considering all of the damage conditions observed from the inspection on RC structural members exposed to fire. In addition, the FDDS was applied to an actual fire-damaged case reported by the Architectural Institute of Japan (AIJ, 2009), and it appears that the proposed method provides a reasonable estimation on the fire damage grade of the fire-damaged RC members.
Influence of Dissolved Ions on the Water Purification Performance of TiO2-Impregnated Porous Silica Tubes
Authors: Hayashi Mio , Ochiai Tsuyoshi , Tago Shoko , Tawarayama Hiromasa , Hosoya Toshifumi , Yahagi Tsukaho , Fujishima Akira
Published: May 2017

TiO2-coated porous silica glass tubes containing macropores were fabricated and evaluated for their water-purification capacity using aqueous solutions of methylene blue. From the results of photocatalytic degradation tests at different initial methylene blue concentrations, the equilibrium adsorption constant (K) was determined to be 4.6 × 10−2 L µmol−1, and the Langmuir-Hinshelwood rate constant (kLH) was calculated as 2.6 µM min−1. To determine the influence of ions on the efficiency of methylene blue degradation, we examined both Milli-Q water (soft water) and Contrex water (hard water) as solvents, and confirmed the reduced purification for the Contrex solution. It was, therefore, considered that the presence of inorganic salts decreased the photocatalytic efficiency. Furthermore, variations in the methylene blue decomposition ability were observed between anion-free and cation-free Contrex. Finally, we concluded that the efficiency of photocatalytic decomposition of TiO2 was influenced by multiple parameters, including the presence of anions and cations, as well as the solution pH.
Modeling the Neutral-Ionic Transition with Correlated Electrons Coupled to Soft Lattices and Molecules
Authors: D’Avino Gabriele , Painelli Anna , Soos Zoltán
Published: May 2017

Neutral-ionic transitions (NITs) occur in organic charge-transfer (CT) crystals of planar π -electron donors (D) and acceptors (A) that form mixed stacks ... D+ρA−ρD+ρA−ρD+ρA−ρ ... with variable ionicity 0 < ρ < 1 and electron transfer t along the stack. The microscopic NIT model presented here combines a modified Hubbard model for strongly correlated electrons delocalized along the stack with Coulomb intermolecular interactions treated in mean field. It also accounts for linear coupling of electrons to a harmonic molecular vibration and to the Peierls phonon. This simple framework captures the observed complexity of NITs with continuous and discontinuous ρ on cooling or under pressure, together with the stack’s instability to dimerization. The interplay of charge, molecular and lattice degrees of freedom at NIT amplifies the nonlinearity of responses, accounts for the dielectric anomaly, and generates strongly anharmonic potential energy surfaces (PES). Dynamics on the ground state PES address vibrational spectra using time correlation functions. When extended to the excited state PES, the NIT model describes the early (<1 ps) dynamics of transient NIT induced by optical CT excitation with a fs pulse. Although phenomenological, the model parameters are broadly consistent with density functional calculations.
Health Literacy amongst Health Professional University Students: A Study Using the Health Literacy Questionnaire
Authors: Mullan Judy , Burns Pippa , Weston Kathryn , McLennan Peter , Rich Warren , Crowther Shelley , Mansfield Kylie , Dixon Robyn , Moselen Emma , Osborne Richard
Published: May 2017

Background: This study aimed to assess and compare health literacy levels in a range of university-based health students. Methods: A survey containing the Health Literacy Questionnaire (HLQ) was administered to students enrolled in university-based medical, allied health or nursing degree programs. The HLQ scores and scale scores were compared across student groups. Results: In total, 374 students (24% response rate) with a median age of 25 years (range: 17–61 years), returned completed surveys. Three students who did not identify their degree programs were excluded from the final analysis which included 371 respondents; 242 graduate-entry medical students (65%), 67 allied health students (18%) and 62 nursing students (17%). Overall, the medical students had the highest score for seven of the nine HLQ scales; while the nursing students had the lowest score for all of the nine HLQ scales. Conclusion: These results show that health literacy profiles are different across student groups. In order to provide excellent patient-centred care, and to successfully look after their own health, a high level of health literacy is required by future health professionals. Health literacy training modules, tailored according to the different needs of the student groups, should therefore be included in university-based health professional degree programs.
Photovoltaic Array Fault Detection by Automatic Reconfiguration
Authors: Ji Dong , Zhang Cai , Lv Mingsong , Ma Ye , Guan Nan
Published: May 2017

Photovoltaic (PV) system output electricity is related to PV cells’ conditions, with the PV faults decreasing the efficiency of the PV system and even causing a possible source of fire. In industrial production, PV fault detection is typically laborious manual work. In this paper, we present a method that can automatically detect PV faults. Based on the observation that different faults will have different impacts on a PV system, we propose a method that systematically and iteratively reconfigures the PV array until the faults are located based on the specific current-voltage (I-V) curve of the (sub-)array. Our method can detect several main types of faults including open-circuit faults, mismatch faults, short circuit faults, etc. We evaluate our methods by Matlab/Simulink-based simulation. The results show that the proposed methods can accurately detect and classify the different faults occurring in a PV system.
Exploration of Wave Development during Yarn Transverse Impact
Authors: Hudspeth Matthew , Jewell Emily , Horner Suzanne , Zheng James , Chen Weinong
Published: May 2017

Single yarns have been impacted in a transverse fashion so as to probe the characteristics of resulting wave development. Longitudinal wave speeds were tracked in efforts to directly measure the yarn tensile stiffness, resulting in a slight increase in the modulus of Kevlar® KM2 and Dyneema® SK76. Additionally, the load developed in AuTx® and Kevlar® KM2 yarns behind the longitudinal wave front has been recorded, providing additional verification for the Smith relations. Further effort to bolster the Smith equations has been successfully performed via tracking transverse wave speeds in AuTx® yarns over a range of impacting velocities. Additional emphasis has been placed at understanding the transverse wave development around the yarn critical velocity, demonstrating that there is a velocity zone where partial yarn failure is detected. Above the critical velocity, measurement of early time transverse wave speeds also agrees with the Smith solution, though the wave speed quickly reduces in value due to the drop in tensile stresses resulting from filament rupture. Finally, the Smith equations have been simplified and are compared to the Cunniff equation, which bear a striking resemblance. Due to such a resemblance, it is suggested that yarn critical velocity experiments can be performed on trial yarn material, and the effect of modifying yarn mechanical properties is discussed.
Influence of Nano-Hydroxyapatite on the Metal Bioavailability, Plant Metal Accumulation and Root Exudates of Ryegrass for Phytoremediation in Lead-Polluted Soil
Authors: Ding Ling , Li Jianbing , Liu Wei , Zuo Qingqing , Liang Shu-xuan
Published: May 2017

Lead is recognized as one of the most widespread toxic metal contaminants and pervasive environmental health concerns in the environment. In this paper, the effects of nano-hydroxyapatite (NHAP) on remediation in artificially Pb-contaminated soils and ryegrass were studied in a pot experiment. The addition of NHAP decreased the water- and acid-soluble, exchangeable, and reducible fractions of Pb, extracted using the Community Bureau of Reference (BCR) method, whilst greatly increasing the residual fraction of Pb. Oxidizable Pb was increased slightly. No significant increase in soil pH was caused by the application of NHAP. Compared to conditions without NHAP, the addition of NHAP decreased the Pb content in ryegrass shoots and roots by 13.19–20.3% and 2.86–21.1%, respectively. Therefore, the application of NHAP reduced the mobility and bioavailability of Pb in the soil. In addition, the application of NHAP improved the fresh weight of shoots and roots, and promoted the growth of ryegrass. NHAP played a positive role in stimulating ryegrass to secrete tartaric acid.
Analysis of Different Approaches for the Selection of Reference Genes in RT-qPCR Experiments: A Case Study in Skeletal Muscle of Growing Mice
Authors: Piazza Verónica , Bartke Andrzej , Miquet Johanna , Sotelo Ana
Published: May 2017

The reliability of reverse transcription-quantitative PCR (RT-qPCR) results in gene expression studies depends on the approaches used to account for non-biological variations. In order to find a proper normalization strategy for the study of genes related to growth hormone signaling in skeletal muscle of growing mice, nine unrelated genes were evaluated as internal controls. According to the most used algorithms–geNorm, the Comparative ΔCq method, NormFinder and BestKeeper–GSK3B, YWHAZ, RPL13A and RN18S were found as the most stable. However, the relative expression levels of eight of the potential reference genes assessed decreased with age in cDNA samples obtained from the same amount of total RNA. In a different approach to analyze this apparent discrepancy, experiments were performed with cDNA obtained from equal amounts of purified mRNA. Since the decline was still observed, the hypothesis of an age-related change in mRNA to total RNA ratio that could account for the systematic decrease was rejected. Differences among experimental groups could be due to a substantial increase with age in highly expressed mRNAs, which would bias the quantitation of the remaining genes. Consequently, those reference genes reflecting this dilution effect, which would have been discarded considering their variable relative expression levels, arose as suitable internal controls.
First Report of a Fatal Case Associated with EV-D68 Infection in Hong Kong and Emergence of an Interclade Recombinant in China Revealed by Genome Analysis
Authors: Yip Cyril , Lo Janice , Sridhar Siddharth , Lung David , Luk Shik , Chan Kwok-Hung , Chan Jasper , Cheng Vincent , Woo Patrick , Yuen Kwok-Yung , Lau Susanna
Published: May 2017

A fatal case associated with enterovirus D68 (EV-D68) infection affecting a 10-year-old boy was reported in Hong Kong in 2014. To examine if a new strain has emerged in Hong Kong, we sequenced the partial genome of the EV-D68 strain identified from the fatal case and the complete VP1, and partial 5′UTR and 2C sequences of nine additional EV-D68 strains isolated from patients in Hong Kong. Sequence analysis indicated that a cluster of strains including the previously recognized A2 strains should belong to a separate clade, clade D, which is further divided into subclades D1 and D2. Among the 10 EV-D68 strains, 7 (including the fatal case) belonged to the previously described, newly emerged subclade B3, 2 belonged to subclade B1, and 1 belonged to subclade D1. Three EV-D68 strains, each from subclades B1, B3, and D1, were selected for complete genome sequencing and recombination analysis. While no evidence of recombination was noted among local strains, interclade recombination was identified in subclade D2 strains detected in mainland China in 2008 with VP2 acquired from clade A. This study supports the reclassification of subclade A2 into clade D1, and demonstrates interclade recombination between clades A and D2 in EV-D68 strains from China.