WorldWideScience

Sample records for standalone self-study suppliment

  1. Stand-alone XLIF

    DEFF Research Database (Denmark)

    Hansen, E. J.; Simony, A.; Hummel, Stefan

    2015-01-01

    and clinical/radiological results in 22 patients treated with XLIF procedure for DS or degenerative disc disease (DDD). Material and methods: 22 consecutive patients with DS underwent surgery with the XLIF stand-alone procedure, with follow-up of 24 months. Clinical outcome scores were collected. Complications......Introduction: Adult thoracolumbar degeneration is an increasing challenge in the aging population. With age the progressive degeneration of the discs leads to an asymmetric collapse and a thoracolumbar coronal plane deformity, a degenerative scoliosis (DS). Aim: To evaluate the complication rate......-year follow-up, with a 31.8% revision rate. Due to the high revision rate we recommend supplementary posterior instrumentation, to achieve a higher fusion rate. When considering XLIF-stand-alone procedure for DS or DDD without supplemental posterior instrumentation, only single-level disease should...

  2. The Stand-alone Heliostat

    International Nuclear Information System (INIS)

    Garcia Navajas, G. I.; Egea Gea, A.

    2000-01-01

    The first Autonomous Heliostat has been developed by CIEMAT at PSA facilities in Almeria. This heliostat is an innovative approach to reducing the civil engineering work costs in heliostat fields of central tower plants. Channels, cables and other electric elements have been eliminated in the new heliostat. Thus, one 70-nr, classical T glass/metal heliostat has been adapted to include all the new stand-alone concept components. A PV system is able to drive two sun-tracking DC motors between 5 and 24Vdc, 0 and 15A. The heliostat communicates with the control room 400-m away by using a radio-modem working at 9600 baud. An anemometer, a wind switcher, light and ambient temperature sensors have been installed on the heliostat for self-protection decision-making. A PV panel integrated into the heliostat reflecting surface, eliminates cabling and other elements required for a conventional power supply. Communication lines between master control and local control have been replaced by radio-modem. Testing has validated the technical feasibility of the prototype and quantified the real consumption and efficiencies of new elements. The extra costs produced.by the autonomous concepts are compared with the cost of civil work in conventional heliostat field. (Author) 8 refs

  3. Stand-alone photovoltaic applications. Lessons learned

    International Nuclear Information System (INIS)

    Loois, G.; Van Hemert, B.

    1999-02-01

    The IEA Photovoltaic Power Systems Programme (PVPS) is one of the collaborative R and D agreements established within the IEA. The objective of Task III is to promote and facilitate the exchange of information and experiences in the field of PV Systems in Stand-alone and Island Applications (SAPV). The book focuses on the practical experiences gained, and does not aim to provide a complete manual on SAPV. When Task III started its activities in 1993, a collection of 50 'State of the art' projects was published in the book 'Examples of Stand-Alone Photovoltaic Systems'. This publication marked the base line for the work of the task. Now, in 1998, the showcases from each country demonstrate the lessons learned in five years of cooperation. The book consists of two parts. The first part contains eight chapters dealing with a specific aspect of stand-alone PV. The second part introduces 14 national showcase projects in a systematic presentation. Each chapter and showcase can be read independently from the rest of the book. Chapter 2, contributed by The Netherlands, analyses the market for stand-alone PV systems. It gives an overview of the 'traditional' application of stand-alone PV, which is the electrification of remote buildings and which has been addressed in depth in other publications. The focus is on the market niches of service applications that are also interesting for more densely populated areas, e.g. in industrialised countries. The United Kingdom illustrates the economic aspects in Chapter 3. Cost comparisons are made, but more important is the illustration of the non-financial considerations that make PV the preferred choice as a power source for many applications. Switzerland explores in Chapter 4 (financing aspects) different financing mechanisms, and financial policies used to overcome the initial cost barrier. Most of these approaches have been applied in developing countries rather than in the western world. Using various examples from all over the

  4. AOF: standalone test results of GALACSI

    Science.gov (United States)

    La Penna, P.; Aller Carpentier, E.; Argomedo, J.; Arsenault, R.; Conzelmann, R. D.; Delabre, B.; Donaldson, R.; Gago, F.; Gutierrez-Cheetam, P.; Hubin, N.; Jolley, P.; Kiekebusch, M.; Kirchbauer, J. P.; Klein, B.; Kolb, J.; Kuntschner, H.; Le Louarn, M.; Lizon, J.-L.; Madec, P.-Y.; Manescau, A.; Mehrgan, L.; Oberti, S.; Quentin, J.; Sedghi, B.; Ströbele, S.; Suárez Valles, M.; Soenke, C.; Tordo, S.; Vernet, J.

    2016-07-01

    GALACSI is the Adaptive Optics (AO) module that will serve the MUSE Integral Field Spectrograph. In Wide Field Mode it will enhance the collected energy in a 0.2"×0.2" pixel by a factor 2 at 750 nm over a Field of View (FoV) of 1'×1' using the Ground Layer AO (GLAO) technique. In Narrow Field Mode, it will provide a Strehl Ratio of 5% (goal 10%) at 650 nm, but in a smaller FoV (7.5"×7.5" FoV), using Laser Tomography AO (LTAO). Before being ready for shipping to Paranal, the system has gone through an extensive testing phase in Europe, first in standalone mode and then in closed loop with the DSM in Europe. After outlining the technical features of the system, we describe here the first part of that testing phase and the integration with the AOF ASSIST (Adaptive Secondary Setup and Instrument Stimulator) testbench, including a specific adapter for the IRLOS truth sensor. The procedures for the standalone verification of the main system performances are outlined, and the results of the internal functional tests of GALACSI after full integration and alignment on ASSIST are presented.

  5. 39 CFR 122.2 - Stand-alone special services.

    Science.gov (United States)

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Stand-alone special services. 122.2 Section 122.2 Postal Service UNITED STATES POSTAL SERVICE POST OFFICE SERVICES [DOMESTIC MAIL] SERVICE STANDARDS FOR MARKET-DOMINANT SPECIAL SERVICES PRODUCTS § 122.2 Stand-alone special services. (a) The service standard...

  6. Stand-alone induction generators for small water power schemes

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, Adam [Intermediate Technology Development Group, Rugby (United Kingdom); Smith, Nigel [Smith Associates, Nottingham (United Kingdom)

    1996-04-01

    Conventional technology for isolated power generation is the synchronous generator. Using stand-alone induction generators has proved to have tremendous advantages in remote regions of developing countries, where electricity has significant social benefits. (author)

  7. Nanotechnology Safety Self-Study

    Energy Technology Data Exchange (ETDEWEB)

    Grogin, Phillip W. [Los Alamos National Laboratory

    2016-03-29

    Nanoparticles are near-atomic scale structures between 1 and 100 nanometers (one billionth of a meter). Engineered nanoparticles are intentionally created and are used in research and development at Sandia National Laboratories (SNL) and Los Alamos National Laboratory (LANL). This course, Nanotechnology Safety Self-Study, presents an overview of the hazards, controls, and uncertainties associated with the use of unbound engineered nanoscale particles (UNP) in a laboratory environment.

  8. Synchronisation of two separate zones in a standalone microgrid

    Directory of Open Access Journals (Sweden)

    Ying-Yi Hong

    2017-06-01

    Full Text Available Standalone microgrids that comprise distributed generation sources (DGSs or energy storage systems (ESSs exist on off-shore islands or remote areas. When a fault occurs in a standalone microgrid, the microgrid is separated into several zones with pre-specified DGS or ESS supplying power to local loads. After the fault is cleared, the three-phase voltages and frequencies may differ among these zones. To restore the original microgrid topology, these zones must be reconnected to each other by synchronisation. A synchronisation controller of the DGS/ESS that accounts for slightly different three-phase voltages and frequencies in two separate zones is presented. The Clark transform and Mamdani fuzzy rules are used to implement the controller, providing fast and seamless synchronisation. Simulation results using a standalone microgrid show the practical applicability of the proposed method.

  9. A New Approach for Optimal Sizing of Standalone Photovoltaic Systems

    OpenAIRE

    Khatib, Tamer; Mohamed, Azah; Sopian, K.; Mahmoud, M.

    2012-01-01

    This paper presents a new method for determining the optimal sizing of standalone photovoltaic (PV) system in terms of optimal sizing of PV array and battery storage. A standalone PV system energy flow is first analysed, and the MATLAB fitting tool is used to fit the resultant sizing curves in order to derive general formulas for optimal sizing of PV array and battery. In deriving the formulas for optimal sizing of PV array and battery, the data considered are based on five sites in Malaysia...

  10. The stand-alone test and decreasing serial cost sharing

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Thorlund-Petersen, Lars

    2000-01-01

    The rule of decreasing serial cost sharing defined in de Frutos [1] over the class of concave cost functions may violate the important stand-alone test. Sufficient conditions for the test to be satisfied are given, in terms of individual rationality as well as coalitional stability...

  11. Stand-alone solutions, computer networks and extern communications

    International Nuclear Information System (INIS)

    Tarschisch, H.

    1988-01-01

    The advantages of local networks over stand-alone solutions are presented. Of the local networks (LAN), two are presently at the center of attention: the bus and the ring. ETHERNET and the IBM-Token-Ring are described as typical examples. Access to public networks, especially TELEPAC and ISDN, is discussed. 12 figs

  12. Standalone General Purpose Data Logger Design and Implementation

    African Journals Online (AJOL)

    This paper describes the design of a general purpose data logger that is compatible with a variety of transducers, potentially permitting the measurement and recording of a wide range of phenomena. The recorded data can be retrieved to a PC via an RS-232 serial port. The standalone general purpose data logger ...

  13. A review on sizing methodologies of photovoltaic array and storage battery in a standalone photovoltaic system

    International Nuclear Information System (INIS)

    Khatib, Tamer; Ibrahim, Ibrahim A.; Mohamed, Azah

    2016-01-01

    Highlights: • We review the current methods for sizing standalone PV systems. • We review the current criteria adapted in sizing standalone PV systems. • We review current method for sizing battery in standalone PV systems. - Abstract: The reliance of future energy demand on standalone PV system is based on its payback period and particular electrical grid parity prices. This highlights the importance for optimum and applicable methods for sizing these systems. Moreover, the designers are being more sensitive toward simple and reliable sizing models for standalone PV system. This paper proposes a review on important knowledge that needs to be taken into account while designing and implementing standalone PV systems. Such a knowledge includes configurations of standalone photovoltaic system, evaluation criteria for unit sizing, sizing methodologies. Moreover, this review provides highlights on challenges and limitations of standalone PV system size optimization techniques.

  14. A New Approach for Optimal Sizing of Standalone Photovoltaic Systems

    Directory of Open Access Journals (Sweden)

    Tamer Khatib

    2012-01-01

    Full Text Available This paper presents a new method for determining the optimal sizing of standalone photovoltaic (PV system in terms of optimal sizing of PV array and battery storage. A standalone PV system energy flow is first analysed, and the MATLAB fitting tool is used to fit the resultant sizing curves in order to derive general formulas for optimal sizing of PV array and battery. In deriving the formulas for optimal sizing of PV array and battery, the data considered are based on five sites in Malaysia, which are Kuala Lumpur, Johor Bharu, Ipoh, Kuching, and Alor Setar. Based on the results of the designed example for a PV system installed in Kuala Lumpur, the proposed method gives satisfactory optimal sizing results.

  15. Models for a stand-alone PV system

    DEFF Research Database (Denmark)

    Hansen, A.D.; Sørensen, Poul Ejnar; Hansen, L.H.

    2001-01-01

    are based on the model descriptions found in the literature. The battery model is developed at UMASS and is known as the Kinetic Battery Model(KiBaM). The other component models in the PV system are based on simple electrical knowledge. The implementation is done using Matlab/Simulink, a simulation program......This report presents a number of models for modelling and simulation of a stand-alone photovoltaic (PV) system with a battery bank verified against a system installed at Risø National Laboratory. The work has been supported by the Danish Ministry ofEnergy, as a part of the activities in the Solar...... Energy Centre Denmark. The study is carried out at Risø National Laboratory with the main purpose to establish a library of simple mathematical models for each individual element of a stand-alone PVsystem, namely solar cells, battery, controller, inverter and load. The models for PV module and battery...

  16. Optimal sizing method for stand-alone photovoltaic power systems

    Energy Technology Data Exchange (ETDEWEB)

    Groumpos, P P; Papageorgiou, G

    1987-01-01

    The total life-cycle cost of stand-alone photovoltaic (SAPV) power systems is mathematically formulated. A new optimal sizing algorithm for the solar array and battery capacity is developed. The optimum value of a balancing parameter, M, for the optimal sizing of SAPV system components is derived. The proposed optimal sizing algorithm is used in an illustrative example, where a more economical life-cycle cost has bene obtained. The question of cost versus reliability is briefly discussed.

  17. Models for a stand-alone PV system[Photovoltaic

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, A.D.; Soerensen, P.; Hansen, L.H.; Bindner, H.

    2000-12-01

    This report presents a number of models for modelling and simulation of a stand-alone photovoltaic (PV) system with a battery bank verified against a system installed at Risoe National Laboratory. The work has been supported by the Danish Ministry of Energy, as a part of the activities in the Solar Energy Centre Denmark. The study is carried out at Risoe National Laboratory with the main purpose to establish a library of simple mathematical models for each individual element of a stand-alone PV system, namely solar cells, battery, controller, inverter and load. The models for PV module and battery are based on the model descriptions found in the literature. The battery model is developed at UMASS and is known as the Kinetic Battery Model (KiBaM). The other component models in the PV system are based on simple electrical knowledge. The implementation is done using Matlab/Simulink, a simulation program that provides a graphical interface for building models as modular block diagrams. The non-linear behaviour of the battery, observed in the measurements, is investigated and compared to the KiBaM model's performance. A set of linear Black box models are estimated based on the battery measurements. The performance of the best linear Black box model is compared to the KiBaM model. A validation of each of the implemented mathematical model is performed by an interactive analysis and comparison between simulation results and measurements, acquired from the stand-alone PV system at Risoe. (au)

  18. Availability model of stand-alone photovoltaic system

    Science.gov (United States)

    Mazurek, G.

    2017-08-01

    In this paper we present a simple, empirical model of stand-alone photovoltaic power system availability. The model is a final result of five-year long studies and ground measurements of solar irradiation carried out in Central Europe. The obtained results facilitate sizing of PV modules that have to be installed with taking into account system's availability level in each month of a year. The model can be extended to different geographical locations, with help of local meteorological data or solar irradiation datasets derived from satellite measurements.

  19. A Standalone Vision Impairments Simulator for Java Swing Applications

    Science.gov (United States)

    Oikonomou, Theofanis; Votis, Konstantinos; Korn, Peter; Tzovaras, Dimitrios; Likothanasis, Spriridon

    A lot of work has been done lately in an attempt to assess accessibility. For the case of web rich-client applications several tools exist that simulate how a vision impaired or colour-blind person would perceive this content. In this work we propose a simulation tool for non-web JavaTM Swing applications. Developers and designers face a real challenge when creating software that has to cope with a lot of interaction situations, as well as specific directives for ensuring an accessible interaction. The proposed standalone tool will assist them to explore user-centered design and important accessibility issues for their JavaTM Swing implementations.

  20. Future UK markets for stand-alone renewable energy systems

    International Nuclear Information System (INIS)

    Paish, O.

    1999-01-01

    A study to identify and quantify the market for stand-alone renewable energy supplies of power (photovoltaics, wind and micro-hydro electricity systems) was described. The study focused on small systems, generally less than a few kW installed capacity. It was suggested that in the UK, the emphasis on grid-connected renewable energy technologies (RETs) has blurred the fact that it is 'off-grid' renewable systems that can offer more immediate real commercial markets for the renewables business. With the likelihood of a significant increase in demand for renewables world wide over the next ten years, the UK needs to make a special effort to become involved

  1. Enhanced current and voltage regulators for stand-alone applications

    DEFF Research Database (Denmark)

    Federico, de Bosio; Pastorelli, Michele; Antonio DeSouza Ribeiro, Luiz

    2016-01-01

    State feedback decoupling permits to achieve a better dynamic response for Voltage Source in stand-alone applications. The design of current and voltage regulators is performed in the discrete-time domain since it provides better accuracy and allows direct pole placement. As the attainable...... bandwidth of the current loop is mainly limited by computational and PWM delays, a lead compensator structure is proposed to overcome this limitation. The design of the voltage regulator is based on the Nyquist criterion, verifying to guarantee a high sensitivity peak. Discrete-time domain implementation...

  2. Flammable Gas Safety Self-Study 52827

    Energy Technology Data Exchange (ETDEWEB)

    Glass, George [Los Alamos National Laboratory

    2016-03-17

    This course, Flammable Gas Safety Self-Study (COURSE 52827), presents an overview of the hazards and controls associated with commonly used, compressed flammable gases at Los Alamos National Laboratory (LANL).

  3. Validation of the standalone implementation of the dynamic wake meandering model for power production

    DEFF Research Database (Denmark)

    Keck, Rolf-Erik Henrik Jussi

    2015-01-01

    This paper presents validation for using the standalone implementation of the dynamic wake meandering (DWM) model to conduct numerical simulations of power production of rows of wind turbines. The standalone DWM model is an alternative formulation of the conventional DWM model that does not require...... information exchange with an aeroelastic code. As a consequence, the standalone DWM model has significantly shorter computational times and lower demands on the user environment. The drawback of the standalone DWM model is that it does not have the capability to predict turbine loads. Instead, it should...

  4. Coding considerations for standalone molecular dynamics simulations of atomistic structures

    Science.gov (United States)

    Ocaya, R. O.; Terblans, J. J.

    2017-10-01

    The laws of Newtonian mechanics allow ab-initio molecular dynamics to model and simulate particle trajectories in material science by defining a differentiable potential function. This paper discusses some considerations for the coding of ab-initio programs for simulation on a standalone computer and illustrates the approach by C language codes in the context of embedded metallic atoms in the face-centred cubic structure. The algorithms use velocity-time integration to determine particle parameter evolution for up to several thousands of particles in a thermodynamical ensemble. Such functions are reusable and can be placed in a redistributable header library file. While there are both commercial and free packages available, their heuristic nature prevents dissection. In addition, developing own codes has the obvious advantage of teaching techniques applicable to new problems.

  5. Hydrogen Gas Production in a Stand-Alone Wind Farm

    Directory of Open Access Journals (Sweden)

    M. Naziry Kordkandy

    2017-04-01

    Full Text Available This paper is analyzing the operation of a stand-alone wind farm with variable speed turbines, permanent magnet synchronous generators (PMSG and a system for converting wind energy during wind speed variations. On this paper, the design and modeling of a wind system which uses PMSG’s to provide the required power of a hydrogen gas electrolyzer system, is discussed. This wind farm consists of three wind turbines, boost DC-DC converters, diode full bridge rectifiers, permanent magnet synchronous generators, MPPT control and a hydrogen gas electrolyzer system. The MPPT controller based on fuzzy logic is designed to adjust the duty ratio of the boost DC-DC converters to absorb maximum power. The proposed fuzzy logic controller assimilates, with (PSF MPPT algorithm which generally used to absorb maximum power from paralleled wind turbines and stores it in form of hydrogen gas. The system is modeled and its behavior is studied using the MATLAB software.

  6. Magnetic field measurements near stand-alone transformer stations.

    Science.gov (United States)

    Kandel, Shaiela; Hareuveny, Ronen; Yitzhak, Nir-Mordechay; Ruppin, Raphael

    2013-12-01

    Extremely low-frequency (ELF) magnetic field (MF) measurements around and above three stand-alone 22/0.4-kV transformer stations have been performed. The low-voltage (LV) cables between the transformer and the LV switchgear were found to be the major source of strong ELF MFs of limited spatial extent. The strong fields measured above the transformer stations support the assessment method, to be used in future epidemiological studies, of classifying apartments located right above the transformer stations as highly exposed to MFs. The results of the MF measurements above the ground around the transformer stations provide a basis for the assessment of the option of implementing precautionary procedures.

  7. Standalone visualization tool for three-dimensional DRAGON geometrical models

    International Nuclear Information System (INIS)

    Lukomski, A.; McIntee, B.; Moule, D.; Nichita, E.

    2008-01-01

    DRAGON is a neutron transport and depletion code able to solve one-, two- and three-dimensional problems. To date DRAGON provides two visualization modules, able to represent respectively two- and three-dimensional geometries. The two-dimensional visualization module generates a postscript file, while the three dimensional visualization module generates a MATLAB M-file with instructions for drawing the tracks in the DRAGON TRACKING data structure, which implicitly provide a representation of the geometry. The current work introduces a new, standalone, tool based on the open-source Visualization Toolkit (VTK) software package which allows the visualization of three-dimensional geometrical models by reading the DRAGON GEOMETRY data structure and generating an axonometric image which can be manipulated interactively by the user. (author)

  8. Integral type small PWR with stand-alone safety

    International Nuclear Information System (INIS)

    Makihara, Yoshiaki

    2001-01-01

    A feasibility study is achieved on an integral type small PWR with stand-alone safety. It is designed to have the following features. (1) The coolant does not leak out at any accidental condition. (2) The fuel failure does never occur while it is supposed on the large scale PWR at the design base accident. (3) At any accidental condition the safety is secured without any support from the outside (stand-alone safety secure). (4) It has self-regulating characteristics and easy controllability. The above features can be satisfied by integrate the steam generator and CRDM in the reactor vessel while the pipe line break has to be considered on the conventional PWR. Several counter measures are planned to satisfy the above features. The economy feature is also attained by several simplifications such as (1) elimination of main coolant piping and pressurizer by the integration of primary cooling system and self-pressurizing, (2) elimination of RCP by application of natural circulating system, (3) elimination of ECCS and accumulator by application of static safety system, (4) large scale volume reduction of the container vessel by application of integrated primary cooling system, (5) elimination of boric acid treatment by deletion of chemical shim. The long operation period such as 10 years can be attained by the application of Gd fuel in one batch refueling. The construction period can be shortened by the standardizing the design and the introduction of modular component system. Furthermore the applicability of the reduced modulation core is also considered. (K. Tsuchihashi)

  9. A fully integrated standalone portable cavity ringdown breath acetone analyzer

    Science.gov (United States)

    Sun, Meixiu; Jiang, Chenyu; Gong, Zhiyong; Zhao, Xiaomeng; Chen, Zhuying; Wang, Zhennan; Kang, Meiling; Li, Yingxin; Wang, Chuji

    2015-09-01

    Breath analysis is a promising new technique for nonintrusive disease diagnosis and metabolic status monitoring. One challenging issue in using a breath biomarker for potential particular disease screening is to find a quantitative relationship between the concentration of the breath biomarker and clinical diagnostic parameters of the specific disease. In order to address this issue, we need a new instrument that is capable of conducting real-time, online breath analysis with high data throughput, so that a large scale of clinical test (more subjects) can be achieved in a short period of time. In this work, we report a fully integrated, standalone, portable analyzer based on the cavity ringdown spectroscopy technique for near-real time, online breath acetone measurements. The performance of the portable analyzer in measurements of breath acetone was interrogated and validated by using the certificated gas chromatography-mass spectrometry. The results show that this new analyzer is useful for reliable online (online introduction of a breath sample without pre-treatment) breath acetone analysis with high sensitivity (57 ppb) and high data throughput (one data per second). Subsequently, the validated breath analyzer was employed for acetone measurements in 119 human subjects under various situations. The instrument design, packaging, specifications, and future improvements were also described. From an optical ringdown cavity operated by the lab-set electronics reported previously to this fully integrated standalone new instrument, we have enabled a new scientific tool suited for large scales of breath acetone analysis and created an instrument platform that can even be adopted for study of other breath biomarkers by using different lasers and ringdown mirrors covering corresponding spectral fingerprints.

  10. A fully integrated standalone portable cavity ringdown breath acetone analyzer.

    Science.gov (United States)

    Sun, Meixiu; Jiang, Chenyu; Gong, Zhiyong; Zhao, Xiaomeng; Chen, Zhuying; Wang, Zhennan; Kang, Meiling; Li, Yingxin; Wang, Chuji

    2015-09-01

    Breath analysis is a promising new technique for nonintrusive disease diagnosis and metabolic status monitoring. One challenging issue in using a breath biomarker for potential particular disease screening is to find a quantitative relationship between the concentration of the breath biomarker and clinical diagnostic parameters of the specific disease. In order to address this issue, we need a new instrument that is capable of conducting real-time, online breath analysis with high data throughput, so that a large scale of clinical test (more subjects) can be achieved in a short period of time. In this work, we report a fully integrated, standalone, portable analyzer based on the cavity ringdown spectroscopy technique for near-real time, online breath acetone measurements. The performance of the portable analyzer in measurements of breath acetone was interrogated and validated by using the certificated gas chromatography-mass spectrometry. The results show that this new analyzer is useful for reliable online (online introduction of a breath sample without pre-treatment) breath acetone analysis with high sensitivity (57 ppb) and high data throughput (one data per second). Subsequently, the validated breath analyzer was employed for acetone measurements in 119 human subjects under various situations. The instrument design, packaging, specifications, and future improvements were also described. From an optical ringdown cavity operated by the lab-set electronics reported previously to this fully integrated standalone new instrument, we have enabled a new scientific tool suited for large scales of breath acetone analysis and created an instrument platform that can even be adopted for study of other breath biomarkers by using different lasers and ringdown mirrors covering corresponding spectral fingerprints.

  11. R and D into stand-alone PV systems for export

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    The current status of photovoltaic (PV) technology is reviewed for systems to provide electricity where mains supplies are unavailable, known as stand-alone PV systems. Typical applications and experiences with installed stand-alone systems are described. Economic issues and barriers to the wide use of PV systems are also examined. (UK)

  12. Respirators: APR Issuer Self Study 33461

    Energy Technology Data Exchange (ETDEWEB)

    Chochoms, Michael [Los Alamos National Laboratory

    2016-07-13

    Respirators: APR Issuer Self-Study (course 33461) is designed to introduce and familiarize employees selected as air-purifying respirator (APR) issuers at Los Alamos National Laboratory (LANL) with the responsibilities, limitations, procedures, and resources for issuing APRs at LANL. The goal is to enable these issuers to consistently provide proper, functioning APRs to authorized users

  13. Simulation of potential standalone liquid desiccant cooling cycles

    International Nuclear Information System (INIS)

    Das, Rajat Subhra; Jain, Sanjeev

    2015-01-01

    LDCS (Liquid desiccant cooling systems), capable of achieving dehumidification and cooling with low-grade heat input, can be effectively used for treating fresh air in hot and humid regions. These can also be operated using non-concentrating solar collectors. The present study is concerned with the evaluation of various potential liquid desiccant cycles for tropical climatic conditions. Six potential standalone liquid desiccant cycles are identified and analyzed to select the best configuration for achieving thermal comfort. A computer simulation model is developed in EES (Equation Solver) software platform to evaluate the performance of all the cycles at various operating conditions. Aqueous solution of LiCl (lithium chloride) is used as desiccant. Mass and energy balance equations of all the components along with their effectiveness and LiCl property correlation equations are solved simultaneously for given ambient conditions. As the desiccant circuit is a closed loop, no assumptions are made about its concentration and temperature in the algorithm. Supply air conditions, cooling capacity, COP (capacity and coefficient of performance) and CR (circulation rate) per unit cooling capacity and hot water temperature requirement are used as a measure for analyzing the performance of the different cycles. The effect of hot water temperature on the performance of the cycles is evaluated at ARI conditions. The performances of the cycles are also evaluated for cities selected from each of the climatic zone of India that represent typical tropical climates. Although all the cycles are feasible at ARI and hot and dry conditions, only two cycles can achieve the selected indoor conditions in the peak humid conditions. The results would be useful for selecting suitable liquid desiccant cycle for a given climate. - Highlights: • Six potential standalone liquid desiccant cycles identified and analyzed to select best configuration. • A computer simulation model is developed in

  14. Simulation of load-sharing in standalone distributed generation system

    Science.gov (United States)

    Ajewole, Titus O.; Craven, Robert P. M.; Kayode, Olakunle; Babalola, Olufisayo S.

    2018-05-01

    This paper presents a study on load-sharing among the component generating units of a multi-source electric microgrid that is operated as an autonomous ac supply-mode system. Emerging trend in power system development permits deployment of microgrids for standalone or stand-by applications, thereby requiring active- and reactive power sharing among the discrete generating units contained in hybrid-source microgrids. In this study, therefore, a laboratory-scale model of a microgrid energized with three renewable energy-based sources is employed as a simulation platform to investigate power sharing among the power-generating units. Each source is represented by a source emulator that captures the real operational characteristics of the mimicked generating unit and, with implementation of real-life weather data and load profiles on the model; the sharing of the load among the generating units is investigated. There is a proportionate generation of power by the three source emulators, with their frequencies perfectly synchronized at the point of common coupling as a result of balance flow of power among them. This hybrid topology of renewable energy-based microgrid could therefore be seamlessly adapted into national energy mix by the indigenous electric utility providers in Nigeria.

  15. A control strategy for PV stand-alone applications

    Science.gov (United States)

    Slouma, S.; Baccar, H.

    2015-04-01

    This paper proposes a stand-alone photovoltaic (PV) system study in domestic applications. Because of the decrease in power of photovoltaic module as a consequence of changes in solar radiation and temperature which affect the photovoltaic module performance, the design and control of DC-DC buck converter was proposed for providing power to the load from a photovoltaic source.In fact, the control of this converter is carried out with integrated MPPT (Maximum Power Point Tracking) algorithm which ensures a maximum energy generated by the PV arrays. Moreover, the output stage is composed by a battery energy storage system, dc-ac inverter, LCL filter which enables higher efficiency, low distortion ac waveforms and low leakage currents. The control strategy adopted is cascade control composed by two regulation loops.Simulations performed with PSIM software were able to validate the control system.The realization and testing of the photovoltaic system were achieved in the Photovoltaic laboratory of the Centre for Research and Energy Technologies at the Technopark Borj Cedria. Experimental results verify the effeciency of the proposed system.

  16. A control strategy for PV stand-alone applications

    International Nuclear Information System (INIS)

    Slouma, S; Baccar, H

    2015-01-01

    This paper proposes a stand-alone photovoltaic (PV) system study in domestic applications. Because of the decrease in power of photovoltaic module as a consequence of changes in solar radiation and temperature which affect the photovoltaic module performance, the design and control of DC-DC buck converter was proposed for providing power to the load from a photovoltaic source.In fact, the control of this converter is carried out with integrated MPPT (Maximum Power Point Tracking) algorithm which ensures a maximum energy generated by the PV arrays. Moreover, the output stage is composed by a battery energy storage system, dc-ac inverter, LCL filter which enables higher efficiency, low distortion ac waveforms and low leakage currents. The control strategy adopted is cascade control composed by two regulation loops.Simulations performed with PSIM software were able to validate the control system.The realization and testing of the photovoltaic system were achieved in the Photovoltaic laboratory of the Centre for Research and Energy Technologies at the Technopark Borj Cedria. Experimental results verify the effeciency of the proposed system

  17. The Stand-alone Heliostat; El Heliostato Autonomo

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Navajas, G.; Egea Gea, A. [Ciemat. Madrid (Spain)

    2000-07-01

    The first Autonomous Heliostat has been developed by CIEMAT at PSA facilities in Almeria. This heliostat is an innovative approach to reducing the civil engineering work costs in heliostat fields of central tower plants. Channels, cables and other electric elements have been eliminated in the new heliostat. Thus, one 70-m''2, classical T glass/metal heliostat has been adapted to include all the new stand-alone concept components. A PV system is able to drive two sun-tracking DC motors between 5 and 24 Vdc, 0 and 15A. The heliostat communicates with the control room 400-m away by using a radio-modern working at 9600 baud. An anemometer, a wind switcher, light and ambient temperature sensors have been installed on the heliostat for self-protection decision-making. A PV panel integrated into the heliostat reflecting surface, eliminates cabling and other elements required for a conventional power supply. Communication lines between master control and local control have been replaced by radio-modern. Testing has validated the technical feasibility of the prototype and quantified the real consumption and efficiencies of new elements. The extra costs produced by the autonomous concepts are compared with the cost of civil work in conventional heliostat field. (Author) 8 refs.

  18. The Stand-alone Heliostat; El Heliostato Autonomo

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Navajas, G; Egea Gea, A [Ciemat. Madrid (Spain)

    2000-07-01

    The first Autonomous Heliostat has been developed by CIEMAT at PSA facilities in Almeria. This heliostat is an innovative approach to reducing the civil engineering work costs in heliostat fields of central tower plants. Channels, cables and other electric elements have been eliminated in the new heliostat. Thus, one 70-m''2, classical T glass/metal heliostat has been adapted to include all the new stand-alone concept components. A PV system is able to drive two sun-tracking DC motors between 5 and 24 Vdc, 0 and 15A. The heliostat communicates with the control room 400-m away by using a radio-modern working at 9600 baud. An anemometer, a wind switcher, light and ambient temperature sensors have been installed on the heliostat for self-protection decision-making. A PV panel integrated into the heliostat reflecting surface, eliminates cabling and other elements required for a conventional power supply. Communication lines between master control and local control have been replaced by radio-modern. Testing has validated the technical feasibility of the prototype and quantified the real consumption and efficiencies of new elements. The extra costs produced by the autonomous concepts are compared with the cost of civil work in conventional heliostat field. (Author) 8 refs.

  19. Foldit Standalone: a video game-derived protein structure manipulation interface using Rosetta.

    Science.gov (United States)

    Kleffner, Robert; Flatten, Jeff; Leaver-Fay, Andrew; Baker, David; Siegel, Justin B; Khatib, Firas; Cooper, Seth

    2017-09-01

    Foldit Standalone is an interactive graphical interface to the Rosetta molecular modeling package. In contrast to most command-line or batch interactions with Rosetta, Foldit Standalone is designed to allow easy, real-time, direct manipulation of protein structures, while also giving access to the extensive power of Rosetta computations. Derived from the user interface of the scientific discovery game Foldit (itself based on Rosetta), Foldit Standalone has added more advanced features and removed the competitive game elements. Foldit Standalone was built from the ground up with a custom rendering and event engine, configurable visualizations and interactions driven by Rosetta. Foldit Standalone contains, among other features: electron density and contact map visualizations, multiple sequence alignment tools for template-based modeling, rigid body transformation controls, RosettaScripts support and an embedded Lua interpreter. Foldit Standalone is available for download at https://fold.it/standalone , under the Rosetta license, which is free for academic and non-profit users. It is implemented in cross-platform C ++ and binary executables are available for Windows, macOS and Linux. scooper@ccs.neu.edu. © The Author(s) 2017. Published by Oxford University Press.

  20. Respirators: Supervisors Self-Study #43442

    Energy Technology Data Exchange (ETDEWEB)

    Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-04-20

    This course, Respirators: Supervisors Self-Study (#43442), addresses training requirements for supervisors of respirator wearers as specified by the American National Standard Institute (ANSI) Standard for Respiratory Protection, ANSI Z88.2, and as incorporated by reference in the Department of Energy (DOE) Worker Health and Safety Rule, 10 Code of Federal Regulations (CFR) 851. This course also presents the responsibilities of supervisors of respirator wearers at Los Alamos National Laboratory (LANL).

  1. Pressure Safety: Advanced Self-Study 30120

    Energy Technology Data Exchange (ETDEWEB)

    Glass, George [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-29

    Pressure Safety Advance Self-Study (Course 30120) consists of an introduction, five modules, and a quiz. To receive credit in UTrain for completing this course, you must score 80% or better on the 15-question quiz (check UTrain). Directions for initiating the quiz are appended to the end of this training manual. This course contains several links to LANL websites. UTrain might not support active links, so please copy links into the address line in your browser.

  2. Non-Integrated Standalone Tests of APR1400 Simulator

    International Nuclear Information System (INIS)

    Hwang, Su Hyun; Lee, Jeong Ik; Hong, Soon Joon; Lee, Byung Chul; Seo, Jeong Gwan; Lee, Myung Soo

    2007-01-01

    APR1400 being developed for the construction of New Kori 3 and 4 Units has improved safety and more economical efficiency compared with previous PWR. The ESF(Engineered Safety Features) newly introduced to enhance safety are as follows: DVI (Direct Vessel Injection), Fluidic Device, IRWST (In-containment Refueling Water Storage Tank). So the transient pattern of anticipated accidents will show different characteristics from previous PWR. There are multidimensional flow phenomena like as emergency core cooling coolant bypass discharge in the downcomer, downcomer boiling, and different safety injection characteristics due to fluidic device during LBLOCA. Also there is the phenomenon of critical flow due to the open of pressurizer POSRV (Pilot Operated Safety Relief valve) connected to IRWST and safety depressurization system and the prediction of discharge flow is very important. KEPRI is developing APR1400 simulator using RELAP-RT . RELAP-RT was developed by DS and S (Data systems and Solutions) based on RELAP5/MOD3.2. The improved features of RELAP-RT to function as a simulator are as follows: Add simulator functionality - Control by simulator executive - IC snap and reset capability - Back-track snap and reset capability - Fast time capability. Fast time capability(examples) - The rate of condensation has been limited. - Fictional choking model has been developed for internal junctions. - Wall heat transfer coefficients and heat fluxes has been limited. In this study, various NISTs (Non-Integrated Standalone Tests) were performed to verify the capability of RELAP-RT as APR1400 simulator by the comparison with RELAP5/MOD3.3

  3. Seismic stability of a standalone glove box structure

    Energy Technology Data Exchange (ETDEWEB)

    Saraswat, A., E-mail: anupams@barc.gov.in [Bhabha Atomic Research Centre, Mumbai (India); Reddy, G.R. [Bhabha Atomic Research Centre, Mumbai (India); Ghosh, S. [Indian Institute of Technology Bombay, Mumbai (India); Ghosh, A.K.; Kumar, Arun [Bhabha Atomic Research Centre, Mumbai (India)

    2014-09-15

    Highlights: • Glove box is a leak tight, safety related structure used for handling radiotoxic materials. • To study the seismic performance of a freestanding glove box, extensive shake table testing has been carried out. • Glove box maintained structural integrity and leak tightness up to design basis earthquake loading. • Detailed three-dimensional finite element model of the structure is developed and analyzed by using direct time integration methods. • Simplified numerical method is proposed and successfully applied, to quickly estimate sliding displacement and determine upper bounds for it. - Abstract: In a nuclear fuel cycle facility, radiotoxic materials are being handled in freestanding leak tight enclosures called glove boxes (GBs). These glove boxes act as a primary confinement for the radiotoxic materials. Glove boxes are designed as per codal requirements for class I component. They are designed to withstand extreme level of earthquake loading with a return period of 10,000 years. To evaluate seismic performance of the glove box, there is a need to check the stability (sliding and overturning), structural integrity (stresses and strains) and leak tightness under earthquake loading. Extensive shake table experiments were conducted on a single standalone glove box. Actual laboratory conditions were simulated during testing to check the response. After extensive shake table testing, glove box structure was also analyzed using finite element (FE) software. Detailed three-dimensional model of glove box structure was developed and analyzed using nonlinear time history method. It was observed that finite element methods could be utilized to accurately predict dynamic response of glove box structure. This paper discusses the details and results of shake table testing and methodology used for modelling and analysing freestanding glove box structure under seismic loading. In addition, simplified numerical procedure, developed using energy conservation

  4. Seismic stability of a standalone glove box structure

    International Nuclear Information System (INIS)

    Saraswat, A.; Reddy, G.R.; Ghosh, S.; Ghosh, A.K.; Kumar, Arun

    2014-01-01

    Highlights: • Glove box is a leak tight, safety related structure used for handling radiotoxic materials. • To study the seismic performance of a freestanding glove box, extensive shake table testing has been carried out. • Glove box maintained structural integrity and leak tightness up to design basis earthquake loading. • Detailed three-dimensional finite element model of the structure is developed and analyzed by using direct time integration methods. • Simplified numerical method is proposed and successfully applied, to quickly estimate sliding displacement and determine upper bounds for it. - Abstract: In a nuclear fuel cycle facility, radiotoxic materials are being handled in freestanding leak tight enclosures called glove boxes (GBs). These glove boxes act as a primary confinement for the radiotoxic materials. Glove boxes are designed as per codal requirements for class I component. They are designed to withstand extreme level of earthquake loading with a return period of 10,000 years. To evaluate seismic performance of the glove box, there is a need to check the stability (sliding and overturning), structural integrity (stresses and strains) and leak tightness under earthquake loading. Extensive shake table experiments were conducted on a single standalone glove box. Actual laboratory conditions were simulated during testing to check the response. After extensive shake table testing, glove box structure was also analyzed using finite element (FE) software. Detailed three-dimensional model of glove box structure was developed and analyzed using nonlinear time history method. It was observed that finite element methods could be utilized to accurately predict dynamic response of glove box structure. This paper discusses the details and results of shake table testing and methodology used for modelling and analysing freestanding glove box structure under seismic loading. In addition, simplified numerical procedure, developed using energy conservation

  5. Clinical outcome of stand-alone ALIF compared to posterior instrumentation for degenerative disc disease

    DEFF Research Database (Denmark)

    Udby, Peter M.; Bech-Azeddine, Rachid

    2015-01-01

    The objective of the article was to: a) present results from a case cohort pilot study comparing stand-alone ALIF and TLIF and, b) review the literature on studies comparing the clinical outcome of stand-alone ALIF with posterior instrumentation including TLIF or PLIF, in patients with disabling...... low back pain resulting from degenerative disc disease. ALIF surgery has previously been linked with certain high risk complications and unfavorable long term fusion results. Newer studies suggest that stand-alone ALIF can possibly be advantageous compared to other types of posterior instrumented...

  6. Harmonics reduction in standalone DFIG-DC system by shunt active ...

    Indian Academy of Sciences (India)

    Himanshu Misra

    2018-05-22

    May 22, 2018 ... Doubly fed induction generator; standalone; DC voltage regulation; shunt active filter; harmonics ... Operation and design issue of DFIG in DC-net interface is ...... control systems for the operation of DFIGs in wind energy.

  7. Procedures for Determining the Performance of Stand-Alone Photovoltaic Systems; TOPICAL

    International Nuclear Information System (INIS)

    DeBlasio, R.; Durand, S.; Hansen, R.; Hutchinson, P.; Kroposki, B.; McNutt, P.; Rosenthal, A.; Thomas, M.

    1999-01-01

    This document provides the procedures for determining the performance of stand-alone PV systems. The procedures in this document provide a common approach for evaluating whether a given PV system is suitable to perform the function for which it was designed and manufactured to accomplish, and whether it will provide adequate power to run the load. These procedures cover small stand-alone PV systems. They cover complete outdoor system testing. Test results are valid only for the system that is tested

  8. A review on recent size optimization methodologies for standalone solar and wind hybrid renewable energy system

    International Nuclear Information System (INIS)

    Al-falahi, Monaaf D.A.; Jayasinghe, S.D.G.; Enshaei, H.

    2017-01-01

    Highlights: • Possible combinations and configurations for standalone PV-WT HES were discussed. • Most recently used assessment parameters for standalone PV-WT HES were explained. • Optimization algorithms and software tools were comprehensively reviewed. • The recent trend of using hybrid algorithms over single algorithms was discussed. • Optimization algorithms for sizing standalone PV-WT HES were critically compared. - Abstract: Electricity demand in remote and island areas are generally supplied by diesel or other fossil fuel based generation systems. Nevertheless, due to the increasing cost and harmful emissions of fossil fuels there is a growing trend to use standalone hybrid renewable energy systems (HRESs). Due to the complementary characteristics, matured technologies and availability in most areas, hybrid systems with solar and wind energy have become the popular choice in such applications. However, the intermittency and high net present cost are the challenges associated with solar and wind energy systems. In this context, optimal sizing is a key factor to attain a reliable supply at a low cost through these standalone systems. Therefore, there has been a growing interest to develop algorithms for size optimization in standalone HRESs. The optimal sizing methodologies reported so far can be broadly categorized as classical algorithms, modern techniques and software tools. Modern techniques, based on single artificial intelligence (AI) algorithms, are becoming more popular than classical algorithms owing to their capabilities in solving complex optimization problems. Moreover, in recent years, there has been a clear trend to use hybrid algorithms over single algorithms mainly due to their ability to provide more promising optimization results. This paper aims to present a comprehensive review on recent developments in size optimization methodologies, as well as a critical comparison of single algorithms, hybrid algorithms, and software tools

  9. Stand-alone photovoltaic systems in the Netherlands. Evaluation of the market introduction

    International Nuclear Information System (INIS)

    Cloin, J.; Van Dijk, A.L.; Westra, C.A.

    1999-08-01

    The policy followed for stand-alone PV systems in the Netherlands is evaluated for the period 1997-1998. The world-wide powerful growth of the PV industry is not being followed by the increase in volume of implemented stand-alone PV systems in the Netherlands. This leads to the question whether the Dutch policy to stimulate stand-alone PV systems is effective. Recommendations on the use of communication as a strategic instrument are given, including the drawing up of a marketing plan. Other recommendations include increased transparency in the application for subsidies and a pro-active role of the Netherlands Agency for Energy and the Environment (Novem) in the contact with relevant market parties. The increased focus on product development aimed at the environmental benefits and general reliability of PV systems is recommended. 38 refs

  10. Connecting embedded and stand-alone peer mentoring models to enhance student engagement

    Directory of Open Access Journals (Sweden)

    Rhys Cooper

    2018-03-01

    Full Text Available This paper outlines the Trident Student Mentoring Program that runs in the College of Engineering at Victoria University, Melbourne, Australia. The program offers both embedded and stand-alone models of peer mentoring services to the same cohort of first-year students. It shows that by forming strong links between these two types of peer mentoring models, the inherent challenges of both, such as low attendance rates in stand-alone models and short periods of peer to peer time in embedded models, are mitigated.

  11. Sensorless direct voltage control of the stand-alone brushless doubly-fed generator

    DEFF Research Database (Denmark)

    Liu, Yi; Xu, Wei; Xiong, Fei

    2017-01-01

    The conventional stand-alone brushless doubly-fed generator (BDFG) control strategies need the feedback from the rotor position or speed sensors, which can reduce system reliability and increase the cost and axial volume of the machine. In this paper, a sensorless direct voltage control (DVC) str......) strategy is presented for the stand-alone BDFG. The satisfactory dynamic performance is verified by experimental results under four kinds of typical operation conditions. Besides, the proposed control strategy is robust due to no generator parameters being required....

  12. Linguistic and Structural Analyses of Stand-Alone Literature Reviews: Seventy-Five Years of Change

    Science.gov (United States)

    Wright, Heidi Rachel

    2016-01-01

    The purpose of this dissertation is to offer a multifaceted overview of stand-alone literature reviews. These texts, literature reviews published unattached to research articles, have existed for centuries but remained largely unstudied by linguists. Thus, the goal of this project is to present these reviews' situational, grammatical, and…

  13. Assessment of Stand-Alone Displays for Time Management in a Creativity-Driven Learning Environment

    DEFF Research Database (Denmark)

    Frimodt-Møller, Søren

    2017-01-01

    This paper considers the pros and cons of stand-alone displays, analog (e.g. billboards, blackboards, whiteboards, large pieces of paper etc.) as well as digital (e.g. large shared screens, digital whiteboards or similar), as tools for time management processes in a creativity-driven learning...

  14. Stand-alone version of the 11kW Gaia wind turbine

    DEFF Research Database (Denmark)

    Bindner, H.; Rosas, P.A.C.; Teodorescu, R.

    2004-01-01

    This report describes the development of a stand-alone version of the 11kW Gaia wind turbine. Various possible configurations are investigated and a configuration using a back-to-back converter is chosen. A model is developed for controller design of thefast controllers of the unit. Controllers...... assessment and controller design a dynamic performance assessment model has been developed....

  15. A maximum power point tracking scheme for a 1kw stand-alone ...

    African Journals Online (AJOL)

    A maximum power point tracking scheme for a 1kw stand-alone solar energy based power supply. ... Nigerian Journal of Technology ... A method for efficiently maximizing the output power of a solar panel supplying a load or battery bus under ...

  16. Use of Super-Capacitor to Enhance Charging Performance of Stand-Alone Solar PV System

    KAUST Repository

    Huang, B. J.; Hsu, P. C.; Ho, P. Y

    2011-01-01

    Introduction: The battery charging performance in a stand-alone solar PV system affects the PV system efficiency and the load operating time. The New Energy Center of National Taiwan University has been devoted to the development of a PWM charging

  17. Assessment of renewable energy resources potential for large scale and standalone applications in Ethiopia

    NARCIS (Netherlands)

    Tucho, Gudina Terefe; Weesie, Peter D.M.; Nonhebel, Sanderine

    2014-01-01

    This study aims to determine the contribution of renewable energy to large scale and standalone application in Ethiopia. The assessment starts by determining the present energy system and the available potentials. Subsequently, the contribution of the available potentials for large scale and

  18. Evaluating a Pre-Session Homework Exercise in a Standalone Information Literacy Class

    Science.gov (United States)

    Goetz, Joseph E.; Barber, Catherine R.

    2015-01-01

    In this study, researchers evaluate a homework exercise assigned before a standalone information literacy session. Students in a Master of Education program completed a worksheet using the ERIC database thesaurus. The researchers conducted pre- and posttests within a single library session to assess student learning, using a control group for…

  19. Environmental/Climatic Effect on Stand-Alone Solar Energy Supply ...

    African Journals Online (AJOL)

    This paper investigates the climatic eects and environmental variations on the performance of a stand-alone photovoltaic system. The eects of partial shading with dierent climate conditions and load resistance variations were examined. A survey of some of the work done in this eld of environmental eect on solar panel was ...

  20. Demonstration of Load-Follow Simulation with VERA-CS and Standalone BISON

    Energy Technology Data Exchange (ETDEWEB)

    Stimpson, Shane G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-01-24

    In this report, load-follow simulations using VERA-CS with one-way coupling to standalone BISON has been demonstrated including both a single rod with a full cycle of load-follow operations and a quarter-core model with a single month of load-follow.

  1. Modelling of fluid-solid interaction using two stand-alone codes

    CSIR Research Space (South Africa)

    Grobler, Jan H

    2010-01-01

    Full Text Available A method is proposed for the modelling of fluid-solid interaction in applications where fluid forces dominate. Data are transferred between two stand-alone codes: a dedicated computational fluid dynamics (CFD) code capable of free surface modelling...

  2. Long-Range Self-Study, 1975-1985.

    Science.gov (United States)

    Williamsport Area Community Coll., PA.

    This self-study contains recommendations and objectives for Williamsport Area Community College (WACC), a one-campus, vocational-technical oriented college in an industrial community in Pennsylvania. The methodology employed in producing this self-study is intended to form the framework for a continuous learning-oriented short and long-range…

  3. Facilitating Collaborative Work in Tertiary Teaching: A Self-Study

    Science.gov (United States)

    Verenikina, Irina

    2012-01-01

    This paper reports on a self-study undertaken by the author to better understand the educational practices of scaffolding in pre-service teachers' collaborative group work. The method included student interviews, conversations with a critical friend, and the researcher's diary. The self-study allowed for fine-tuning theoretical understanding and…

  4. Self-Study Centre: Help, Fun, and Interdependence.

    Science.gov (United States)

    Cardoso, Janaina

    This paper discusses the development and use of student self-study centers in language programs, focusing on the experiences of a language teacher in developing such a center at Cultura Inglesia in Rio de Janeiro, Brazil. Self-study centers may be defined as a set of facilities aimed at providing students with the opportunity of learning…

  5. Journaling and Self-Study in an International Research Collective

    Science.gov (United States)

    Makaiau, Amber Strong; Leng, Lu; Fukui, Suguru

    2015-01-01

    Drawing from the theoretical foundations of reflective teaching, culturally responsive education, social constructivism, and self-study, this collaborative self-study investigates the role of an interactive online journal in an international research collective. Each from a different country, the authors came together through a common interest in…

  6. Dynamic performance improvement of standalone battery integrated PMSG wind energy system using proportional resonant controller

    Directory of Open Access Journals (Sweden)

    Dileep Kumar Varma Sagiraju

    2017-08-01

    Full Text Available The load voltage and frequency should be controlled under steady state and transient conditions in off grid applications. Power quality and power management is very important task for rural communities under erratic wind and load conditions. This paper presents a coordinated Proportional resonant (PR and battery energy controller for enhancement of power quality and power management in direct drive standalone wind energy system. The dynamic performance of standalone direct drive Permanent Magnet Synchronous Generator (PMSG is investigated with the proposed control scheme under various operating conditions such as fluctuating wind with step increase and decrease in wind velocity, balanced and unbalanced load conditions. The proposed PR control strategy with battery energy controller also ensures effective power balance between wind and battery source in order to fulfill the load demand. The superiority of the proposed control strategy is confirmed by comparing with the traditional vector control strategy under fluctuating wind and load conditions through MATLAB/SIMULINK platform.

  7. Hybrid Configuration of Darrieus and Savonius Rotors for Stand-alone Power Systems

    Science.gov (United States)

    Wakui, Tetsuya; Tanzawa, Yoshiaki; Hashizume, Takumi; Nagao, Toshio

    The suitable hybrid configuration of Darrieus lift-type and Savonius drag-type rotors for stand-alone wind turbine-generator systems is discussed using our dynamic simulation model. Two types of hybrid configurations are taken up: Type-A installs the Savonius rotor inside the Darrieus rotor and Type-B installs the Savonius rotor outside the Darrieus rotor. The computed results of the output characteristics and the dynamic behaviors of the system operated at the maximum power coefficient points show that Type-A, which has fine operating behavior to wind speed changes and can be compactly designed because of a shorter rotational shaft, is an effective way for self-controlled stand-alone small-scale systems.

  8. Impact of Battery’s Model Accuracy on Size Optimization Process of a Standalone Photovoltaic System

    Directory of Open Access Journals (Sweden)

    Ibrahim Anwar Ibrahim

    2016-09-01

    Full Text Available This paper presents a comparative study between two proposed size optimization methods based on two battery’s models. Simple and complex battery models are utilized to optimally size a standalone photovoltaic system. Hourly meteorological data are used in this research for a specific site. Results show that by using the complex model of the battery, the cost of the system is reduced by 31%. In addition, by using the complex battery model, the sizes of the PV array and the battery are reduced by 5.6% and 30%, respectively, as compared to the case which is based on the simple battery model. This shows the importance of utilizing accurate battery models in sizing standalone photovoltaic systems.

  9. Stand-alone version of the 11kW Gaia wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Bindner, H.; Rosas, P.A.C.; Teodorescu, R.; Blaabjerg, F.

    2004-09-15

    This report describes the development of a stand-alone version of the 11kW Gaia wind turbine. Various possible configurations are investigated and a configuration using a back-to-back converter is chosen. A model is developed for controller design of the fast controllers of the unit. Controllers are designed and a prototype is built for testing. The report documents the performance of the prototype through measurements done on the full scale prototype installed in a test facility where it has been tested both as a standalone unit and in parallel with a diesel genset. For system wide power quality assessment and controller design a dynamic performance assessment model has been developed. (au)

  10. Stand-alone wind system with Vanadium Redox Battery energy storage

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Barote, L.; Weissbach, R.

    2008-01-01

    Energy storage devices are required for power balance and power quality in stand alone wind energy systems. A Vanadium Redox Flow Battery (VRB) system has many features which make its integration with a stand-alone wind energy system attractive. This paper proposes the integration of a VRB system...... with a typical stand-alone wind energy system during wind speed variation as well as transient performance under variable load. The investigated system consists of a variable speed wind turbine with permanent magnet synchronous generator (PMSG), diode rectifier bridge, buck-boost converter, bidirectional charge...... controller, transformer, inverter, ac loads and VRB (to store a surplus of wind energy and to supply power during a wind power shortage). The main purpose is to supply domestic appliances through a single phase 230V, 50Hz inverter. Simulations are accomplished in order to validate the stability of the supply....

  11. Stand-Alone Microgrid Inverter Controller Design for Nonlinear, Unbalanced Load with Output Transformer

    Directory of Open Access Journals (Sweden)

    Jae-Uk Lim

    2018-04-01

    Full Text Available This paper proposes a technique that compensates for unbalance and nonlinearity in microgrid inverters with power transformers operating in stand-alone mode. When a microgrid inverter is operating in stand-alone mode, providing high-quality power is very important. When an unbalanced, nonlinear load is connected, zero sequence current and negative sequence current occur, which leads to an unbalanced output voltage. This paper examines why the zero sequence component occurs differently depending on the structure of a three-phase transformer connected to the inverter output terminal, and it proposes a method for controlling the zero sequence component. It also uses a resonant controller to remove the harmonics that correspond to the negative sequence component and the nonlinear component. The proposed elements were verified by a Powersim (PSIM simulation.

  12. A Three-Port Topology Comparison for a Low Power Stand-Alone Photovoltaic System

    DEFF Research Database (Denmark)

    Mira Albert, Maria del Carmen; Knott, Arnold; Andersen, Michael A. E.

    2014-01-01

    Three-port converter (TPC) topologies for renewable energy systems aim to provide higher efficiency and power density than conventional cascaded structures. This work proposes an analytical comparison of different TPC topologies for a photovoltaic LED lamp stand-alone system. A comparison using c...... component stress factor (CSF) is performed, which gives a quantitative measure of the performance of the converter. The candidate topologies are compared to each other according to a defined LED lighting strategy and a solar irradiation profile.......Three-port converter (TPC) topologies for renewable energy systems aim to provide higher efficiency and power density than conventional cascaded structures. This work proposes an analytical comparison of different TPC topologies for a photovoltaic LED lamp stand-alone system. A comparison using...

  13. Analysis and controller design for stand-alone VSIs in synchronous reference frame

    DEFF Research Database (Denmark)

    Ramezani, Malek; Li, Shuhui; Golestan, Saeed

    2017-01-01

    -by-step graphical analysis and design approach for a three-phase stand-alone VSI system in the dq reference frame, which provides a clear systematic decoupling process to design the inner- and outer-loop current and voltage controllers, respectively. The closed-loop d- and q-axis output impedances of the stand......-alone VSI system by considering the coupling effects between axes are also formulated, modelled, and evaluated. The study investigates how the decoupling and compensating terms added in the current and voltage controllers affect the dynamic performance and output dq impedances of the VSI system. Simulation...... and hardware results verify the effectiveness of the graphic design and analysis strategy....

  14. Modeling and Control of the Distributed Power Converters in a Standalone DC Microgrid

    Directory of Open Access Journals (Sweden)

    Xiaodong Lu

    2016-03-01

    Full Text Available A standalone DC microgrid integrated with distributed renewable energy sources, energy storage devices and loads is analyzed. To mitigate the interaction among distributed power modules, this paper describes a modeling and control design procedure for the distributed converters. The system configuration and steady-state analysis of the standalone DC microgrid under study are discussed first. The dynamic models of the distributed converters are then developed from two aspects corresponding to their two operating modes, device-regulating mode and bus-regulating mode. Average current mode control and linear compensators are designed accordingly for each operating mode. The stability of the designed system is analyzed at last. The operation and control design of the system are verified by simulation results.

  15. COMBINATION THERAPIES OR STANDALONE INTERVENTIONS? INNOVATION OPTIONS FOR PHARMACEUTICAL FIRMS FIGHTING CANCER

    OpenAIRE

    GUNJAN BHARDWAJ; ANSHIT AGRAWAL; RUPESH TYAGI

    2015-01-01

    Innovation is key to the pharma model, from an initial discovery to the final development of a marketable drug. Here, we explore the innovation options in the fiercely contested therapeutic area of Oncology. We studied clinical development of drugs targeting PD-1 and PD-L1 pathway. In this interesting contest, companies seem to be focusing on standalone interventions (exploratory innovation) and combination therapy (exploitative innovation) in clinical development. Merck Sharp and Dohme, havi...

  16. MOSFET Loss Evaluation for a Low-Power Stand-Alone Photovoltaic-LED System

    DEFF Research Database (Denmark)

    Mira Albert, Maria del Carmen; Knott, Arnold; Andersen, Michael A. E.

    2015-01-01

    This paper presents a performance evaluation and comparison of state-of-the-art low voltage Si MOSFETs for a stand-alone photovoltaic-LED Light to Light (LtL) system. The complete system is formed by two cascaded converters that will be optimized for a determined solar irradiation and LED...... illumination profiles. The comparison is performed based on dynamic characterization and evaluation of the devices energy loss at different current levels....

  17. Stand-Alone Solar Organic Rankine Cycle Water Pumping System and Its Economic Viability in Nepal

    OpenAIRE

    Suresh Baral; Kyung Chun Kim

    2015-01-01

    The current study presents the concept of a stand-alone solar organic Rankine cycle (ORC) water pumping system for rural Nepalese areas. Experimental results for this technology are presented based on a prototype. The economic viability of the system was assessed based on solar radiation data of different Nepalese geographic locations. The mechanical power produced by the solar ORC is coupled with a water pumping system for various applications, such as drinking and irrigation. The thermal ef...

  18. Methodology for the design of a stand-alone photovoltaic power supply

    OpenAIRE

    López Seguel, Julio; Seleme Junior, Seleme Isaac; Donoso-Garcia, Pedro F; Ferreira Morais, Lenin Martins; Cabaleiro Cortizo, Porfirio; Severo Mendes, Marcos A

    2013-01-01

    This paper presents a complete methodology for the design of an autonomous photovoltaic system to maximize the use of solar energy. It is a method that prioritizes the best cost-effective choice at every step of the project. In order to ensure the proper use and extended battery life time, a control strategy for charging the batteries is proposed. Experimental results are provided for a stand-alone photovoltaic system with low electrical power, intended primarily for the illumination and basi...

  19. Environmental impacts of producing bioethanol and biobased lactic acid from standalone and integrated biorefineries using a consequential and an attributional life cycle assessment approach

    DEFF Research Database (Denmark)

    Parajuli, Ranjan; Knudsen, Marie Trydeman; Birkved, Morten

    2017-01-01

    : a standalone system producing bioethanol from winter wheat-straw (system A), a standalone system producing biobased lactic acid from alfalfa (system B), and an integrated biorefinery system (system C) combining the two standalone systems and producing both bioethanol and lactic acid. The synergy...

  20. Structure Optimization of Stand-Alone Renewable Power Systems Based on Multi Object Function

    Directory of Open Access Journals (Sweden)

    Jae-Hoon Cho

    2016-08-01

    Full Text Available This paper presents a methodology for the size optimization of a stand-alone hybrid PV/wind/diesel/battery system while considering the following factors: total annual cost (TAC, loss of power supply probability (LPSP, and the fuel cost of the diesel generator required by the user. A new optimization algorithm and an object function (including a penalty method are also proposed; these assist with designing the best structure for a hybrid system satisfying the constraints. In hybrid energy system sources such as photovoltaic (PV, wind, diesel, and energy storage devices are connected as an electrical load supply. Because the power produced by PV and wind turbine sources is dependent on the variation of the resources (sun and wind and the load demand fluctuates, such a hybrid system must be able to satisfy the load requirements at any time and store the excess energy for use in deficit conditions. Therefore, reliability and cost are the two main criteria when designing a stand-alone hybrid system. Moreover, the operation of a diesel generator is important to achieve greater reliability. In this paper, TAC, LPSP, and the fuel cost of the diesel generator are considered as the objective variables and a hybrid teaching–learning-based optimization algorithm is proposed and used to choose the best structure of a stand-alone hybrid PV/wind/diesel/battery system. Simulation results from MATLAB support the effectiveness of the proposed method and confirm that it is more efficient than conventional methods.

  1. Use of appliances in stand-alone PV power supply systems: problems and solutions. Task 3 use of photovoltaic power systems in stand-alone and island applications

    Energy Technology Data Exchange (ETDEWEB)

    Vallve, X.; Gafas, G. [IEA PVPS, Task 3 (Spain); Villoz, M. [IEA PVPS, Task 3 (Switzerland); Wilshaw, A. [IEA PVPS, Task 3 (United Kingdom); Jacquin, P. [IEA PVPS, Task 3 (France)

    2002-09-15

    In Stand-Alone Photovoltaic Systems (SAPV systems), special attention must be paid to the used appliances and loads. Inappropriate loads are very often the origin of PV system malfunction or failure. Start-up power peaks, or reactive power and harmonic distortion can cause system signal instability and protective devices will close the system down. A well-matched load together with a carefully selected choice of appliances can lead to significant savings in terms of reduced need for PV and electricity storage capacity. Conversely, inefficient appliances and processes, standby loads and inappropriate loads will increase the requirement for expensive PV and storage capacity. This paper presents a survey of real cases with load related problems in worldwide applications, their effect on quality and cost of the service and the solutions that were adopted and suggested alternative solutions. One of the main conclusions of the work is the importance to integrate the choice of the appliance while designing the SAPV system. (author)

  2. Minimum cost solution of wind–photovoltaic based stand-alone power systems for remote consumers

    International Nuclear Information System (INIS)

    Kaldellis, J.K.; Zafirakis, D.; Kavadias, K.

    2012-01-01

    Renewable energy sources (RES) based stand-alone systems employing either wind or solar power and energy storage comprise a reliable energy alternative, on top of conventional diesel-electric generator sets, commonly used by remote consumers. However, such systems usually imply the need for oversizing and considerable energy storage requirements leading to relatively high costs. On the other hand, hybrid configurations that may exploit both wind and solar potential of a given area may considerably reduce energy storage capacity and improve the economic performance of the system. In this context, an integrated techno-economic methodology for the evaluation of hybrid wind–photovoltaic stand-alone power systems is currently developed, aiming at the designation of optimum configurations for a typical remote consumer, using economic performance criteria. For the problem investigation, the developed evaluation model is applied to four representative areas of the Greek territory with different wind potential characteristics in order to obtain optimum configurations on the basis of minimum initial investment, 10-year and 20-year total cost. According to the results obtained, the proposed solution is favorably compared with all other stand-alone energy alternatives, reflecting the ability of hybrid systems to adjust even in areas where the local RES potential is not necessarily of high quality. - Highlights: ► Wind- and PV-stand alone systems often imply use of extreme battery capacity. ► Hybrid wind–PV systems may reduce energy storage requirements and associated costs. ► An optimization methodology is developed, based on economic performance criteria. ► Methodology is applied to four Greek regions of different wind potential. ► Results obtained reflect the hybrid solution's advantages over other alternatives.

  3. Optimization of stand-alone photovoltaic systems with hydrogen storage for total energy self-sufficiency

    Energy Technology Data Exchange (ETDEWEB)

    Lund, P D [Helsinki Univ. of Technology, Espoo (Finland). Dept. of Technical Physics

    1991-01-01

    A new method for optimization of stand-alone photovoltaic-hydrogen energy systems is presented. The methodology gives the optimum values for the solar array and hydrogen storage size for any given system configuration and geographical site. Sensitivity analyses have been performed to study the effect of subsystem efficiencies on the total system performance and sizing, and also to identify possibilities for further improvements. Optimum system configurations have also been derived. The results indicate that a solar-hydrogen energy system is a very promising potential alternative for low power applications requiring a total electricity self-sufficiency. (Author).

  4. A Simple Sizing Algorithm for Stand-Alone PV/Wind/Battery Hybrid Microgrids

    Directory of Open Access Journals (Sweden)

    Jing Li

    2012-12-01

    Full Text Available In this paper, we develop a simple algorithm to determine the required number of generating units of wind-turbine generator and photovoltaic array, and the associated storage capacity for stand-alone hybrid microgrid. The algorithm is based on the observation that the state of charge of battery should be periodically invariant. The optimal sizing of hybrid microgrid is given in the sense that the life cycle cost of system is minimized while the given load power demand can be satisfied without load rejection. We also report a case study to show the efficacy of the developed algorithm.

  5. Standalone Photovoltaic System Sizing using Peak Sun Hour Method and Evaluation by TRNSYS Simulation

    OpenAIRE

    Riza, Dimas Firmanda Al; Gilani, Syed Ihtshamul-Haq

    2016-01-01

    This paper presents sizing and evaluation of a standalone photovoltaic system for residential load. Peak Sun Hour method is used to determine photovoltaic panel and battery capacity, then the sizing results is tested and evaluated using hourly time-step transient simulation model by using TRNSYS 16.0. The results shows for typical Malaysian terraced house that have about 6 kWh daily electricity load, the photovoltaic system requirement consist of 1.9 kWp photovoltaic panel and 2200 Ah battery...

  6. Boost converter with combined control loop for a stand-alone photovoltaic battery charge system

    DEFF Research Database (Denmark)

    Mira Albert, Maria del Carmen; Knott, Arnold; Thomsen, Ole Cornelius

    2013-01-01

    frequency avoids perturbations in the load being propagated to the photovoltaic panel and thus deviating the operating point. Linearization of the photovoltaic panel and converter state-space modeling is performed. In order to achieve stable operation under all operating conditions, the photovoltaic panel......The converter control scheme plays an important role in the performance of maximum power point tracking (MPPT) algorithms. In this paper, an input voltage control with double loop for a stand-alone photovoltaic system is designed and tested. The inner current control loop with high crossover...

  7. System design optimization for stand-alone photovoltaic systems sizing by using superstructure model

    International Nuclear Information System (INIS)

    Azau, M A M; Jaafar, S; Samsudin, K

    2013-01-01

    Although the photovoltaic (PV) systems have been increasingly installed as an alternative and renewable green power generation, the initial set up cost, maintenance cost and equipment mismatch are some of the key issues that slows down the installation in small household. This paper presents the design optimization of stand-alone photovoltaic systems using superstructure model where all possible types of technology of the equipment are captured and life cycle cost analysis is formulated as a mixed integer programming (MIP). A model for investment planning of power generation and long-term decision model are developed in order to help the system engineer to build a cost effective system.

  8. Development of a microprocessor controller for stand-alone photovoltaic power systems

    Science.gov (United States)

    Millner, A. R.; Kaufman, D. L.

    1984-01-01

    A controller for stand-alone photovoltaic systems has been developed using a low power CMOS microprocessor. It performs battery state of charge estimation, array control, load management, instrumentation, automatic testing, and communications functions. Array control options are sequential subarray switching and maximum power control. A calculator keypad and LCD display provides manual control, fault diagnosis and digital multimeter functions. An RS-232 port provides data logging or remote control capability. A prototype 5 kW unit has been built and tested successfully. The controller is expected to be useful in village photovoltaic power systems, large solar water pumping installations, and other battery management applications.

  9. Optimum Availability of Standalone Photovoltaic Power Systems for Remote Housing Electrification

    Directory of Open Access Journals (Sweden)

    Tamer Khatib

    2014-01-01

    Full Text Available The availability of PV systems is discussed to determine the optimum availability at which standalone PV systems must be designed. Optimization methods and PV systems software, such as HOMER and PV.MY, were used for this purpose. Six PV systems with six availability levels were analyzed, in terms of wasted energy, cost of energy, battery usage, and power shortages, using real meteorological data. Results show that PV systems with 99% availability are recommended, because of their high reliability and favorably wasted energy.

  10. Design and Operation Studies of A Stand-Alone PV Generation System

    DEFF Research Database (Denmark)

    Hu, Yanting; Chen, Zhe; Zhang, Donglai

    2013-01-01

    This paper discusses the modeling, design and operation of a PV powered stand-alone system, which includes a PV array, a battery bank, power electronic converters and the associated control system. The design considerations are analyzed and a design platform is presented. Furthermore the operation...... modes of the system are described. A power electronic system with the associated control scheme has been proposed and simulation models have been developed. Simulation studies have been conducted on an example system; the results have demonstrated the effectiveness of the presented methods....

  11. Evaluating a Pre-session Exercise in a Standalone Information Literacy Class

    Directory of Open Access Journals (Sweden)

    Joseph E. Goetz

    2015-12-01

    Full Text Available In this study, researchers evaluate a homework exercise assigned before a standalone information literacy session. Students in a Master of Education program completed a worksheet using the ERIC database thesaurus. The researchers conducted pre- and posttests within a single library session to assess student learning, using a control group for comparison. The treatment group did not demonstrate better thesaurus skills than students who had regular library instruction alone, but results pointed the way to targeted improvements of pre-session learning materials. This approach could inform other information literacy homework applications such as flipping the classroom.

  12. State Feedback Decoupling with In-Loop Lead Compensator in Stand-Alone VSIs

    DEFF Research Database (Denmark)

    Federico, de Bosio; Pastorelli, Michele; de Sousa Ribeiro, Luiz Antonio

    2016-01-01

    The performance of current and voltage regulators during transients and steady-state is of primary concern for power converters intended for stand-alone applications. Dynamics performance and command tracking capability are enhanced by actively decoupling the controlled states variables. To further...... widen the current loop bandwidth while still preserving a well-damped system a lead compensator structure on the forward loop is proposed. A 3 kHz bandwidth with 0.707 damping factor is achieved for the inner current controller. Accordingly, also the voltage regulator bandwidth can be widen, thus...

  13. Discrete-Time Domain Modelling of Voltage Source Inverters in Standalone Applications

    DEFF Research Database (Denmark)

    Federico, de Bosio; de Sousa Ribeiro, Luiz Antonio; Freijedo Fernandez, Francisco Daniel

    2017-01-01

    modelling of the LC plant with consideration of delay and sample-and-hold effects on the state feedback cross-coupling decoupling is derived. From this plant formulation, current controllers with wide bandwidth and good relative stability properties are developed. Two controllers based on lead compensation......The decoupling of the capacitor voltage and inductor current has been shown to improve significantly the dynamic performance of voltage source inverters in standalone applications. However, the computation and PWM delays still limit the achievable bandwidth. In this paper a discrete-time domain...

  14. Information systems for the materials management department: stand-alone and enterprise resource planning systems.

    Science.gov (United States)

    2005-03-01

    Materials management information systems (MMISs) incorporate information tools that hospitals can use to automate certain business processes, increase staff compliance with these processes, and identify opportunities for cost savings. Recently, there has been a push by hospital administration to purchase enterprise resource planning (ERP) systems, information systems that promise to integrate many more facets of healthcare business. We offer this article to help materials managers, administrators, and others involved with information system selection understand the changes that have taken place in materials management information systems, decide whether they need a new system and, if so, whether a stand-alone MMIS or an ERP system will be the best choice.

  15. Modeling, Design and Simulation of Stand-Alone Photovoltaic Power Systems with Battery Storage

    Directory of Open Access Journals (Sweden)

    Abd Essalam BADOUD

    2013-06-01

    Full Text Available Stand alone renewable energy based on photovoltaic systems accompanied with battery storage system are beginning to play an important role over the world to supply power to remote areas. The objective of the study reported in this paper is to elaborate and design a bond graphs model for sizing stand-alone domestic solar photovoltaic electricity systems and simulating the performance of the systems in a tropical climate. The systems modelled consist of an array of PV modules, a lead-acid battery, and a number of direct current appliances. This paper proposes the combination of lead acid battery system with a typical stand alone photovoltaic energy system under variable loads. The main activities of this work purpose to establish library graphical models for each individual component of standalone photovoltaic system. Control strategy has been considered to achieve permanent power supply to the load via photovoltaic/battery based on the power available from the sun. The complete model was simulated under two testing including sunny and cloudy conditions. Simulation of the system using Symbols software was performed and the results of simulation show the superior stable control system and high efficiency. These results have been contrasted with real measured data from a measurement campaign plant carried on electrical engineering laboratory of Grenoble using various interconnection schemes are presented.

  16. Modified Chaos Particle Swarm Optimization-Based Optimized Operation Model for Stand-Alone CCHP Microgrid

    Directory of Open Access Journals (Sweden)

    Fei Wang

    2017-07-01

    Full Text Available The optimized dispatch of different distributed generations (DGs in stand-alone microgrid (MG is of great significance to the operation’s reliability and economy, especially for energy crisis and environmental pollution. Based on controllable load (CL and combined cooling-heating-power (CCHP model of micro-gas turbine (MT, a multi-objective optimization model with relevant constraints to optimize the generation cost, load cut compensation and environmental benefit is proposed in this paper. The MG studied in this paper consists of photovoltaic (PV, wind turbine (WT, fuel cell (FC, diesel engine (DE, MT and energy storage (ES. Four typical scenarios were designed according to different day types (work day or weekend and weather conditions (sunny or rainy in view of the uncertainty of renewable energy in variable situations and load fluctuation. A modified dispatch strategy for CCHP is presented to further improve the operation economy without reducing the consumers’ comfort feeling. Chaotic optimization and elite retention strategy are introduced into basic particle swarm optimization (PSO to propose modified chaos particle swarm optimization (MCPSO whose search capability and convergence speed are improved greatly. Simulation results validate the correctness of the proposed model and the effectiveness of MCPSO algorithm in the optimized operation application of stand-alone MG.

  17. Design of a Stand-Alone Photovoltaic Model for Home Lightings and Clean Environment

    Energy Technology Data Exchange (ETDEWEB)

    Ani, Vincent Anayochukwu, E-mail: vincent_ani@yahoo.com [Department of Electronic Engineering, University of Nigeria, Nsukka (Nigeria)

    2016-01-11

    This paper gives a well-documented health risk of fuel-based lighting (kerosene lamps and fuel-powered generators) and proposed a design of a stand-alone solar PV system for sustainable home lightings in rural Nigerian area. The design was done in three different patterns of electricity consumptions with energy efficient lightings (EELs) using two different battery types (Rolls Surrette 6CS25PS and Hoppecke 10 OpzS 1000) on; (i) judicious power consumption, (ii) normal power consumption, and (iii) excess power consumption; and compared them with the incandescent light bulb consumption. The stand-alone photovoltaic energy systems were designed to match the rural Nigerian sunlight and weather conditions to meet the required lightings of the household. The objective function and constraints for the design models were formulated and optimization procedures were used to demonstrate the best solution (reliability at the lowest lifecycle cost). Initial capital costs as well as annualized costs over 5, 10, 15, 20, and 25 years were quantified and documented. The design identified the most cost-effective and reliable solar and battery array among the patterns of electricity consumption with EEL options (judicious power consumption, normal power consumption, and excess power consumption).

  18. Design of Stand-Alone Hybrid Power Generation System at Brumbun Beach Tulungagung East Java

    Science.gov (United States)

    Rahmat, A. N.; Hidayat, M. N.; Ronilaya, F.; Setiawan, A.

    2018-04-01

    Indonesian government insists to optimize the use of renewable energy resources in electricity generation. One of the efforts is launching Independent Energy Village plan. This program aims to fulfill the need of electricity for isolated or remote villages in Indonesia. In order to support the penetration of renewable energy resources in electricity generation, a hybrid power generation system is developed. The simulation in this research is based on the availability of renewable energy resources in Brumbun beach, Tulungagung, East Java. Initially, the electricity was supplied through stand-alone electricity generations which are installed at each house. Hence, the use of electricity between 5 p.m. – 9 p.m. requires high operational costs. Based on the problem above, this research is conducted to design a stand-alone hybrid electricity generation system, which may consist of diesel, wind, and photovoltaic. The design is done by using HOMER software to optimize the use of electricity from renewable resources and to reduce the operation of diesel generation. The combination of renewable energy resources in electricity generation resulted in NPC of 44.680, COE of 0,268, and CO2 emissions of 0,038 % much lower than the use of diesel generator only.

  19. Fuzzy logic control of stand-alone photovoltaic system with battery storage

    Science.gov (United States)

    Lalouni, S.; Rekioua, D.; Rekioua, T.; Matagne, E.

    Photovoltaic energy has nowadays an increased importance in electrical power applications, since it is considered as an essentially inexhaustible and broadly available energy resource. However, the output power provided via the photovoltaic conversion process depends on solar irradiation and temperature. Therefore, to maximize the efficiency of the photovoltaic energy system, it is necessary to track the maximum power point of the PV array. The present paper proposes a maximum power point tracker (MPPT) method, based on fuzzy logic controller (FLC), applied to a stand-alone photovoltaic system. It uses a sampling measure of the PV array power and voltage then determines an optimal increment required to have the optimal operating voltage which permits maximum power tracking. This method carries high accuracy around the optimum point when compared to the conventional one. The stand-alone photovoltaic system used in this paper includes two bi-directional DC/DC converters and a lead-acid battery bank to overcome the scare periods. One converter works as an MPP tracker, while the other regulates the batteries state of charge and compensates the power deficit to provide a continuous delivery of energy to the load. The Obtained simulation results show the effectiveness of the proposed fuzzy logic controller.

  20. A sizing method for stand-alone PV installations with variable demand

    Energy Technology Data Exchange (ETDEWEB)

    Posadillo, R. [Grupo de Investigacion en Energias y Recursos Renovables, Dpto. de Fisica Aplicada, E.P.S., Universidad de Cordoba, Avda. Menendez Pidal s/n, 14004 Cordoba (Spain); Lopez Luque, R. [Grupo de Investigacion de Fisica Para las Energias y Recursos Renovables, Dpto. de Fisica Aplicada, Edificio C2 Campus de Rabanales, 14071 Cordoba (Spain)

    2008-05-15

    The practical applicability of the considerations made in a previous paper to characterize energy balances in stand-alone photovoltaic systems (SAPV) is presented. Given that energy balances were characterized based on monthly estimations, the method is appropriate for sizing installations with variable monthly demands and variable monthly panel tilt (for seasonal estimations). The method presented is original in that it is the only method proposed for this type of demand. The method is based on the rational utilization of daily solar radiation distribution functions. When exact mathematical expressions are not available, approximate empirical expressions can be used. The more precise the statistical characterization of the solar radiation on the receiver module, the more precise the sizing method given that the characterization will solely depend on the distribution function of the daily global irradiation on the tilted surface H{sub g{beta}}{sub i}. This method, like previous ones, uses the concept of loss of load probability (LLP) as a parameter to characterize system design and includes information on the standard deviation of this parameter ({sigma}{sub LLP}) as well as two new parameters: annual number of system failures (f) and the standard deviation of annual number of system failures ({sigma}{sub f}). This paper therefore provides an analytical method for evaluating and sizing stand-alone PV systems with variable monthly demand and panel inclination. The sizing method has also been applied in a practical manner. (author)

  1. Passive cooling of standalone flat PV module with cotton wick structures

    International Nuclear Information System (INIS)

    Chandrasekar, M.; Suresh, S.; Senthilkumar, T.; Ganesh karthikeyan, M.

    2013-01-01

    Highlights: • A simple passive cooling system is developed for standalone flat PV modules. • 30% Reduction in module temperature is observed with developed cooling system. • 15.61% Increase in output power of PV module is found with developed cooling system. • Module efficiency is increased by 1.4% with cooling arrangement. • Lower thermal degradation due to narrow range of temperature characteristics. - Abstract: In common, PV module converts only 4–17% of the incoming solar radiation into electricity. Thus more than 50% of the incident solar energy is converted as heat and the temperature of PV module is increased. The increase in module temperature in turn decreases the electrical yield and efficiency of the module with a permanent structural damage of the module due to prolonged period of thermal stress (also known as thermal degradation of the module). An effective way of improving efficiency and reducing the rate of thermal degradation of a PV module is to reduce the operating temperature of PV module. This can be achieved by cooling the PV module during operation. Hence in the present work, a simple passive cooling system with cotton wick structures is developed for standalone flat PV modules. The thermal and electrical performance of flat PV module with cooling system consisting of cotton wick structures in combination with water, Al 2 O 3 /water nanofluid and CuO/water nanofluid are investigated experimentally. The experimental results are also compared with the thermal and electrical performance of flat PV module without cooling system

  2. Design of a Stand-Alone Photovoltaic (PV Models for Home Lightings and Clean Environment

    Directory of Open Access Journals (Sweden)

    Vincent Anayochukwu Ani

    2016-01-01

    Full Text Available This paper gives a well-documented health risks of fuel-based lighting (kerosene lamps and fuel-powered generators and proposed a design of a stand-alone solar PV system for sustainable home lightings in rural Nigerian area. The design was done in three different patterns of electricity consumptions with energy efficient lightings (EELs using two different battery types (Rolls Surrette 6CS25PS and hoppecke 10 OpzS 1000 on; i judicious power consumption, ii normal power consumption, iii excess power consumption; and compared them with the incandescent light bulb consumption. The stand-alone photovoltaic energy systems were designed to match the rural Nigerian sunlight and weather conditions to meet the required lightings of the household. The objective function and constraints for the design models were formulated and optimization procedure were used to demonstrate the best solution (reliability at the lowest lifecycle cost. Initial capital costs as well as annualized costs over 5, 10, 15, 20, and 25 years were quantified and documented. The design identified the most cost-effective and reliable solar and battery array among the patterns of electricity consumption with energy efficient lighting options (judicious power consumption, normal power consumption, and excess power consumption.

  3. International market assessment of stand-alone photovoltaic power systems for cottage industry applications

    Science.gov (United States)

    Philippi, T. M.

    1981-01-01

    The final result of an international assessment of the market for stand-alone photovoltaic systems in cottage industry applications is reported. Nonindustrialized countries without centrally planned economies were considered. Cottage industries were defined as small rural manufacturers, employing less than 50 people, producing consumer and simple products. The data to support this analysis were obtained from secondary and expert sources in the U.S. and in-country field investigations of the Philippines and Mexico. The near-term market for photovoltaics for rural cottage industry applications appears to be limited to demonstration projects and pilot programs, based on an in-depth study of the nature of cottage industry, its role in the rural economy, the electric energy requirements of cottage industry, and a financial analysis of stand-alone photovoltaic systems as compared to their most viable competitor, diesel driven generators. Photovoltaics are shown to be a better long-term option only for very low power requirements. Some of these uses would include clay mixers, grinders, centrifuges, lathes, power saws and lighting of a workshop.

  4. Coordination Control Strategy for AC/DC Hybrid Microgrids in Stand-Alone Mode

    Directory of Open Access Journals (Sweden)

    Dwi Riana Aryani

    2016-06-01

    Full Text Available Interest in DC microgrids is rapidly increasing along with the improvement of DC power technology because of its advantages. To support the integration process of DC microgrids with the existing AC utility grids, the form of hybrid AC/DC microgrids is considered for higher power conversion efficiency, lower component cost and better power quality. In the system, AC and DC portions are connected through interlink bidirectional AC/DC converters (IC with a proper control system and power management. In the stand-alone operation mode of AC/DC hybrid microgrids, the control of power injection through the IC is crucial in order to maintain the system security. This paper mainly deals with a coordination control strategy of IC and a battery energy storage system (BESS converter under stand-alone operation. A coordinated control strategy for the IC, which considers the state of charge (SOC level of BESS and the load shedding scheme as the last resort, is proposed to obtain better power sharing between AC and DC subgrids. The scheme will be tested with a hybrid AC/DC microgrid, using the tool of the PSCAD/EMTDC software.

  5. Numerical simulation of blast wave propagation in vicinity of standalone prism on flat plate

    Science.gov (United States)

    Valger, Svetlana; Fedorova, Natalya; Fedorov, Alexander

    2018-03-01

    In the paper, numerical simulation of shock wave propagation in the vicinity of a standalone prism and a prism with a cavity in front of it was carried out. The modeling was based on the solution of 3D Euler equations and Fluent software was used as a main computational tool. The algorithm for local dynamic mesh adaptation to high gradients of pressure was applied. The initial stage of the explosion of condensed explosive was described with the help of "Compressed balloon method". The research allowed describing the characteristic stages of the blast in a semi-closed space, the structure of secondary shock waves and their interaction with obstacles. The numerical approach in Fluent based on combining inviscid gas dynamics methods and "Compressed balloon method" was compared with the method which had been used by the authors earlier with the help of AUTODYN and which is based on the use of the hydrodynamic model of a material to describe state of detonation products. For the problem of shock wave propagation in the vicinity of standalone prism the comparison of the simulation results obtained using both the methods with the experimental data was performed on the dependence of static pressure and effective momentum on time for the characteristic points located on prism walls.

  6. Proposed Framework for the Evaluation of Standalone Corpora Processing Systems: An Application to Arabic Corpora

    Directory of Open Access Journals (Sweden)

    Abdulmohsen Al-Thubaity

    2014-01-01

    Full Text Available Despite the accessibility of numerous online corpora, students and researchers engaged in the fields of Natural Language Processing (NLP, corpus linguistics, and language learning and teaching may encounter situations in which they need to develop their own corpora. Several commercial and free standalone corpora processing systems are available to process such corpora. In this study, we first propose a framework for the evaluation of standalone corpora processing systems and then use it to evaluate seven freely available systems. The proposed framework considers the usability, functionality, and performance of the evaluated systems while taking into consideration their suitability for Arabic corpora. While the results show that most of the evaluated systems exhibited comparable usability scores, the scores for functionality and performance were substantially different with respect to support for the Arabic language and N-grams profile generation. The results of our evaluation will help potential users of the evaluated systems to choose the system that best meets their needs. More importantly, the results will help the developers of the evaluated systems to enhance their systems and developers of new corpora processing systems by providing them with a reference framework.

  7. Proposed framework for the evaluation of standalone corpora processing systems: an application to Arabic corpora.

    Science.gov (United States)

    Al-Thubaity, Abdulmohsen; Al-Khalifa, Hend; Alqifari, Reem; Almazrua, Manal

    2014-01-01

    Despite the accessibility of numerous online corpora, students and researchers engaged in the fields of Natural Language Processing (NLP), corpus linguistics, and language learning and teaching may encounter situations in which they need to develop their own corpora. Several commercial and free standalone corpora processing systems are available to process such corpora. In this study, we first propose a framework for the evaluation of standalone corpora processing systems and then use it to evaluate seven freely available systems. The proposed framework considers the usability, functionality, and performance of the evaluated systems while taking into consideration their suitability for Arabic corpora. While the results show that most of the evaluated systems exhibited comparable usability scores, the scores for functionality and performance were substantially different with respect to support for the Arabic language and N-grams profile generation. The results of our evaluation will help potential users of the evaluated systems to choose the system that best meets their needs. More importantly, the results will help the developers of the evaluated systems to enhance their systems and developers of new corpora processing systems by providing them with a reference framework.

  8. International market assessment of stand-alone photovoltaic power systems for cottage industry applications

    Science.gov (United States)

    Philippi, T. M.

    1981-11-01

    The final result of an international assessment of the market for stand-alone photovoltaic systems in cottage industry applications is reported. Nonindustrialized countries without centrally planned economies were considered. Cottage industries were defined as small rural manufacturers, employing less than 50 people, producing consumer and simple products. The data to support this analysis were obtained from secondary and expert sources in the U.S. and in-country field investigations of the Philippines and Mexico. The near-term market for photovoltaics for rural cottage industry applications appears to be limited to demonstration projects and pilot programs, based on an in-depth study of the nature of cottage industry, its role in the rural economy, the electric energy requirements of cottage industry, and a financial analysis of stand-alone photovoltaic systems as compared to their most viable competitor, diesel driven generators. Photovoltaics are shown to be a better long-term option only for very low power requirements. Some of these uses would include clay mixers, grinders, centrifuges, lathes, power saws and lighting of a workshop.

  9. Feasibility and Optimal Design of a Stand-Alone Photovoltaic Energy System for the Orphanage

    Directory of Open Access Journals (Sweden)

    Vincent Anayochukwu Ani

    2014-01-01

    Full Text Available Access to electricity can have a positive psychological impact through a lessening of the sense of exclusion, and vulnerability often felt by the orphanages. This paper presented the simulation and optimization study of a stand-alone photovoltaic power system that produced the desired power needs of an orphanage. Solar resources for the design of the system were obtained from the National Aeronautics and Space Administration (NASA Surface Meteorology and Solar Energy website at a location of 6°51′N latitude and 7°35′E longitude, with annual average solar radiation of 4.92 kWh/m2/d. This study is based on modeling, simulation, and optimization of energy system in the orphanage. The patterns of load consumption within the orphanage were studied and suitably modeled for optimization. Hybrid Optimization Model for Electric Renewables (HOMER software was used to analyze and design the proposed stand-alone photovoltaic power system model. The model was designed to provide an optimal system configuration based on an hour-by-hour data for energy availability and demands. A detailed design, description, and expected performance of the system were presented in this paper.

  10. Robust Power Management Control for Stand-Alone Hybrid Power Generation System

    International Nuclear Information System (INIS)

    Kamal, Elkhatib; Adouane, Lounis; Aitouche, Abdel; Mohammed, Walaa

    2017-01-01

    This paper presents a new robust fuzzy control of energy management strategy for the stand-alone hybrid power systems. It consists of two levels named centralized fuzzy supervisory control which generates the power references for each decentralized robust fuzzy control. Hybrid power systems comprises: a photovoltaic panel and wind turbine as renewable sources, a micro turbine generator and a battery storage system. The proposed control strategy is able to satisfy the load requirements based on a fuzzy supervisor controller and manage power flows between the different energy sources and the storage unit by respecting the state of charge and the variation of wind speed and irradiance. Centralized controller is designed based on If-Then fuzzy rules to manage and optimize the hybrid power system production by generating the reference power for photovoltaic panel and wind turbine. Decentralized controller is based on the Takagi-Sugeno fuzzy model and permits us to stabilize each photovoltaic panel and wind turbine in presence of disturbances and parametric uncertainties and to optimize the tracking reference which is given by the centralized controller level. The sufficient conditions stability are formulated in the format of linear matrix inequalities using the Lyapunov stability theory. The effectiveness of the proposed Strategy is finally demonstrated through a SAHPS (stand-alone hybrid power systems) to illustrate the effectiveness of the overall proposed method. (paper)

  11. Design of a Stand-Alone Photovoltaic Model for Home Lightings and Clean Environment

    International Nuclear Information System (INIS)

    Ani, Vincent Anayochukwu

    2016-01-01

    This paper gives a well-documented health risk of fuel-based lighting (kerosene lamps and fuel-powered generators) and proposed a design of a stand-alone solar PV system for sustainable home lightings in rural Nigerian area. The design was done in three different patterns of electricity consumptions with energy efficient lightings (EELs) using two different battery types (Rolls Surrette 6CS25PS and Hoppecke 10 OpzS 1000) on; (i) judicious power consumption, (ii) normal power consumption, and (iii) excess power consumption; and compared them with the incandescent light bulb consumption. The stand-alone photovoltaic energy systems were designed to match the rural Nigerian sunlight and weather conditions to meet the required lightings of the household. The objective function and constraints for the design models were formulated and optimization procedures were used to demonstrate the best solution (reliability at the lowest lifecycle cost). Initial capital costs as well as annualized costs over 5, 10, 15, 20, and 25 years were quantified and documented. The design identified the most cost-effective and reliable solar and battery array among the patterns of electricity consumption with EEL options (judicious power consumption, normal power consumption, and excess power consumption).

  12. Standalone computer-aided detection compared to radiologists' performance for the detection of mammographic masses

    International Nuclear Information System (INIS)

    Hupse, Rianne; Samulski, Maurice; Imhof-Tas, Mechli W.; Karssemeijer, Nico; Lobbes, Marc; Boetes, Carla; Heeten, Ard den; Beijerinck, David; Pijnappel, Ruud

    2013-01-01

    We developed a computer-aided detection (CAD) system aimed at decision support for detection of malignant masses and architectural distortions in mammograms. The effect of this system on radiologists' performance depends strongly on its standalone performance. The purpose of this study was to compare the standalone performance of this CAD system to that of radiologists. In a retrospective study, nine certified screening radiologists and three residents read 200 digital screening mammograms without the use of CAD. Performances of the individual readers and of CAD were computed as the true-positive fraction (TPF) at a false-positive fraction of 0.05 and 0.2. Differences were analysed using an independent one-sample t-test. At a false-positive fraction of 0.05, the performance of CAD (TPF = 0.487) was similar to that of the certified screening radiologists (TPF = 0.518, P = 0.17). At a false-positive fraction of 0.2, CAD performance (TPF = 0.620) was significantly lower than the radiologist performance (TPF = 0.736, P <0.001). Compared to the residents, CAD performance was similar for all false-positive fractions. The sensitivity of CAD at a high specificity was comparable to that of human readers. These results show potential for CAD to be used as an independent reader in breast cancer screening. (orig.)

  13. A Qualitative Self-Study of Retinitis Pigmentosa

    Science.gov (United States)

    Fourie, Robert James

    2007-01-01

    Retinitis Pigmentosa (RP) is a retinal degenerative disease causing progressive blindness. Most research on RP is biomedical, and mostly from an observer perspective, therefore poorly reflecting the lived experience of having RP. Accordingly, the researcher conducted a retrospective qualitative self-study, to analyze reflections on his own…

  14. A Self-Study on Preparing Future School Leaders

    Science.gov (United States)

    Frick, William C.; Riley, Ann T.

    2010-01-01

    This paper presents a self-study project that goes beyond the surface of praxis to examine the internal academic teaching process of a PK-12 school leader educator. The study systematically relates one professor's intrapersonal struggle and professional challenge in addressing his lived contradiction of teaching aspiring school leaders. Results…

  15. Learning through Leading: A Self-Study in District Administration

    Science.gov (United States)

    Collins, Christina

    2016-01-01

    There is little research in the area of understanding educational leaders' psychological processes. This lack of understanding leaves educational leaders to develop their own sense-making practices while in the complex and stressful act of leading. This self-study, conducted over more than half a school year in 2014-2015, was my own effort to do…

  16. Teacher research as self-study and collaborative activity

    OpenAIRE

    Gade, Sharada

    2015-01-01

    This article highlights two insightful methods for advancing teacher research: practitioner self-study in relation to a range of texts, with which to examine one’s educational landscape; and classroom interventions conceived as a Vygotskian activity, via teacher-researcher collaboration. Both approaches allow teachers and collaborating researchers to share individual expertise across institutional boundaries and engage in creative local action.

  17. Vulnerability: Self-Study's Contribution to Social Justice Education

    Science.gov (United States)

    Knowles, Corinne

    2014-01-01

    Teaching, as a social justice project, seeks to undo and re-imagine oppressive pedagogies in order to transform teachers, their students, and the knowledge with which they work. In this article, I argue that self-study can contribute to social justice in a number of ways by, for instance, making the sometimes limiting norms that frame teaching and…

  18. Respirators: Air Purifying, Self-Study, Course 40723

    Energy Technology Data Exchange (ETDEWEB)

    Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-12-21

    Respirators: Air Purifying Self-Study (COURSE 40723) is designed for Los Alamos National Laboratory (LANL) workers, support services subcontractors, and other LANL subcontractors who work under the LANL Respiratory Protection Program (RPP). This course also meets the air-purifying respirators (APRs) retraining requirement.

  19. Self Study Course for Adult 4-H Leaders.

    Science.gov (United States)

    Colorado State Univ., Ft. Collins. Human Factors Research Lab.

    This self study programed text for training Four H Club leaders covers the value and the objectives of the Four H movement; basic principles of program planning; useful club meeting formats and guidelines for delegating authority; types of learning and examples of planned learning experiences; teaching methods and their objectives; growth and…

  20. Excavation/Fill/Soil Disturbance, Self-Study #31419

    Energy Technology Data Exchange (ETDEWEB)

    Grogin, Phillip W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-02-06

    This course, Excavation/Fill/Soil Disturbance Self-Study (#31419), presents an overview of the hazards, controls, and requirements that affect safe excavations at Los Alamos National Laboratory (LANL). An overview of the LANL excavation/fill/soil disturbance permit (EXID permit) approval process is also presented, along with potholing requirements for planning and performing excavations at LANL.

  1. Arts-Based Self-Study: Documenting the Ripple Effect

    Science.gov (United States)

    Weber, Sandra

    2014-01-01

    Like all forms of inquiry, arts-based self-study research can have unexpected consequences. Although we may start out with a fairly clear objective, the data we generate through arts-based methods might address other questions that are even more important than the ones we thought to ask initially, and our study might have an impact that extends…

  2. Modelling of synchronisation and energy performance of FBE- and LBE-based standalone LTE-U networks

    Directory of Open Access Journals (Sweden)

    Jiamin Li

    2017-06-01

    Full Text Available Without the aid of licensed channel, deploying long-term evolution (LTE networks over unlicensed spectrum (named standalone LTE-U networks faces the difficulty of establishing and maintaining synchronisation between user equipments and base stations. In this work, considering the two modes of listen-before-talk-based channel access scheme, frame-based equipment (FBE and load-based equipment (LBE, the authors propose analytical frameworks to study the successful probability of synchronisation and the energy consumption of synchronisation in a standalone LTE-U network. Specifically, for the LBE mode, the authors also propose a Lattice-Poisson algorithm-based approach to derive the distribution of the channel non-occupancy period of a standalone LTE-U network. Furthermore, the authors explore the impact of diverse protocol parameters of both FBE and LBE modes on the two studied performance metrics. Simulation results demonstrate the accuracy of the analysis, and shed some light on the selection of FBE and LBE for standalone LTE-U networks, in terms of synchronisation, energy consumption, and throughput of standalone LTE-U and Wi-Fi networks.

  3. Charactrization of a Li-ion battery based stand-alone a-Si photovoltaic system

    International Nuclear Information System (INIS)

    Hamid Vishkasougheh, Mehdi; Tunaboylu, Bahadir

    2014-01-01

    Highlights: • An Li-ion battery based stand-alone a-Si PV was designed. The system composed of three a-Si panels with an efficiency of 7% and 40 cells of LFP batteries. • Effects of solar radiation and environmental temperature for three cities, Istanbul, Ankara, and Adana, have been investigated on a-Si panels. • Using transition formulas BSPV outputs are predictable for any location out of standard test condition. - Abstract: The number of photovoltaic (PV) system installations is increasing rapidly. As more people learn about this versatile and often cost-effective power option, this trend will accelerate. This document presents a recommended design for a battery based stand-alone photovoltaic system (BSPV). BSPV system has the ability to be applied in different areas, including warning signals, lighting, refrigeration, communication, residential water pumping, remote sensing, and cathodic protection. The presented calculation method gives a proper idea for a system sizing technique. Based on application load, different scenarios are possible for designing a BSPV system. In this study, a battery based stand-alone system was designed. The electricity generation part is three a-Si panels, which are connected in parallel, and for the storage part LFP (lithium iron phosphate) battery was used. The high power LFP battery packs are 40 cells each 8S5P (configured 8 series 5 parallel). Each individual pack weighs 0.5 kg and is 25.6 V. In order to evaluate the efficiency of a-Si panels with respect to the temperature and the solar irradiation, cities of Istanbul, Ankara and Adana in Turkey were selected. Temperature and solar irradiation were gathered from reliable sources and by using translation equations, current and voltage output of panels were calculated. As a result of these calculations, current and energy outputs were computed by considering an average efficient solar irradiation time value per day in Turkey. The calculated power values were inserted to a

  4. Charactrization of a Li-ion battery based stand-alone a-Si photovoltaic system

    Energy Technology Data Exchange (ETDEWEB)

    Hamid Vishkasougheh, Mehdi, E-mail: mehdi.hamid2@gmail.com [Istanbul Sehir University, Kubakisi Caddesi, No: 27, Altunizade, Uskudar, Istanbul 34662 (Turkey); Tunaboylu, Bahadir [Istanbul Sehir University, Kubakisi Caddesi, No: 27, Altunizade, Uskudar, Istanbul 34662 (Turkey); Marmara Research Center, Materials Institute, PO Box 21, Gebze, Kocaeli 41470 (Turkey)

    2014-11-01

    Highlights: • An Li-ion battery based stand-alone a-Si PV was designed. The system composed of three a-Si panels with an efficiency of 7% and 40 cells of LFP batteries. • Effects of solar radiation and environmental temperature for three cities, Istanbul, Ankara, and Adana, have been investigated on a-Si panels. • Using transition formulas BSPV outputs are predictable for any location out of standard test condition. - Abstract: The number of photovoltaic (PV) system installations is increasing rapidly. As more people learn about this versatile and often cost-effective power option, this trend will accelerate. This document presents a recommended design for a battery based stand-alone photovoltaic system (BSPV). BSPV system has the ability to be applied in different areas, including warning signals, lighting, refrigeration, communication, residential water pumping, remote sensing, and cathodic protection. The presented calculation method gives a proper idea for a system sizing technique. Based on application load, different scenarios are possible for designing a BSPV system. In this study, a battery based stand-alone system was designed. The electricity generation part is three a-Si panels, which are connected in parallel, and for the storage part LFP (lithium iron phosphate) battery was used. The high power LFP battery packs are 40 cells each 8S5P (configured 8 series 5 parallel). Each individual pack weighs 0.5 kg and is 25.6 V. In order to evaluate the efficiency of a-Si panels with respect to the temperature and the solar irradiation, cities of Istanbul, Ankara and Adana in Turkey were selected. Temperature and solar irradiation were gathered from reliable sources and by using translation equations, current and voltage output of panels were calculated. As a result of these calculations, current and energy outputs were computed by considering an average efficient solar irradiation time value per day in Turkey. The calculated power values were inserted to a

  5. A Simple and Reliable Method of Design for Standalone Photovoltaic Systems

    Science.gov (United States)

    Srinivasarao, Mantri; Sudha, K. Rama; Bhanu, C. V. K.

    2017-06-01

    Standalone photovoltaic (SAPV) systems are seen as a promoting method of electrifying areas of developing world that lack power grid infrastructure. Proliferations of these systems require a design procedure that is simple, reliable and exhibit good performance over its life time. The proposed methodology uses simple empirical formulae and easily available parameters to design SAPV systems, that is, array size with energy storage. After arriving at the different array size (area), performance curves are obtained for optimal design of SAPV system with high amount of reliability in terms of autonomy at a specified value of loss of load probability (LOLP). Based on the array to load ratio (ALR) and levelized energy cost (LEC) through life cycle cost (LCC) analysis, it is shown that the proposed methodology gives better performance, requires simple data and is more reliable when compared with conventional design using monthly average daily load and insolation.

  6. STANDALONE PHOTOVOLTAIC SYSTEMS SIZING OPTIMIZATION USING DESIGN SPACE APPROACH: CASE STUDY FOR RESIDENTIAL LIGHTING LOAD

    Directory of Open Access Journals (Sweden)

    D. F. AL RIZA

    2015-07-01

    Full Text Available This paper presents a sizing optimization methodology of panel and battery capacity in a standalone photovoltaic system with lighting load. Performance of the system is identified by performing Loss of Power Supply Probability (LPSP calculation. Input data used for the calculation is the daily weather data and system components parameters. Capital Cost and Life Cycle Cost (LCC is calculated as optimization parameters. Design space for optimum system configuration is identified based on a given LPSP value, Capital Cost and Life Cycle Cost. Excess energy value is used as an over-design indicator in the design space. An economic analysis, including cost of the energy and payback period, for selected configurations are also studied.

  7. Transforming stand-alone expert system into a community of cooperating agents

    CERN Document Server

    Jennings, N R; Aarnts, R P; Fuchs, J; Skarek, Paul

    1993-01-01

    Distributed Artificial Intelligence (DAI) systems in which multiple problem solving agents cooperate to achieve a common objective is a rapidly emerging and promising technology. However, as yet, there have been relatively few reported cases of such systems being employed to tackle real-world problems in realistic domains. One of the reasons for this is that DAI researchers have given virtually no consideration to the process of incorporating pre-existing systems into a community of cooperating agents. Yet reuse is a primary consideration for any organisation with a large software base. To redress the balance, this paper reports on an experiment undertaken at the CERN laboratories, in which two pre-existing and standalone expert systems for diagnosing faults in a particle accelerator were transformed into a community of cooperating agents. The experiences and insights gained during this process provide a valuable first step towards satisfying the needs of potential users of DAI technology - identifying the ty...

  8. Loss-of-load probabilities for stand-alone photovoltaic systems

    International Nuclear Information System (INIS)

    Klein, S.A.; Beckman, W.A.

    1989-01-01

    A general method is presented for estimating the loss-of-load probability of stand-alone photovoltaic systems. The method was developed by correlating simulation results. The simulations were driven with synthetic radiation sequences having the same statistical significance as available historical data. The methods assumes a constant nighttime load and accounts for the distribution and persistence in daily solar radiation data. It is shown that the 10 year average performance of systems having loss-of-load probabilities less than about 0.01 can vary greatly from one ten year period to the next and thereby cannot be considered realistic performance estimates of a system during its lifetime. (author). 26 refs, 15 figs, 4 tabs

  9. Size optimization of stand-alone photovoltaic (PV) room air conditioners

    International Nuclear Information System (INIS)

    Chen, Chien-Wei; Zahedi, A.

    2006-01-01

    Sizing of a stand-alone PV system determines the main cost of the system. PV electricity cost is determined by the amount of solar energy received, hence the actual climate and weather conditions such as solar irradiance and ambient temperature affect the size required and cost of the system. Air conditioning demand also depends on the weather conditions. Therefore, sizing a PV powered air conditioner must consider the characteristics of local climate and temperature. In this paper, sizing procedures and special considerations for air conditioning under Melbourne's climatic conditions is presented. The reliability of various PV-battery size combinations is simulated by MATLAB. As a result, excellent system performance can be predicated.(Author)

  10. Integrated Three-Port DC-DC Converter for Photovoltaic (PV) Battery Stand-alone Systems

    DEFF Research Database (Denmark)

    Ouyang, Ziwei; Andersen, Michael A. E.

    2016-01-01

    of solar energy. Moreover, a novel transformer configuration enables variable turns ratio controlled by the phase between the two current excitations subjected to the primary windings, allowing a wider input/output range. 1 kW experimental prototype has been built to demonstrate a wellmanaged power flow......Several power sources such as PV solar arrays and battery are often used to manage the power flow for a photovoltaic (PV) based stand-alone power system due to the fluctuation nature of solar energy resource, and deliver a continuous power to the users in an appropriate form. Traditionally, three...... different single-input single-output (SISO) dc/dc converters would have been used. To reduce the cost and improve the power density of the system, an integrated three-port isolated dc/dc converter is proposed in this paper. It can realize all functions of the energy delivery due to the fluctuation nature...

  11. Study of Stand-Alone Microgrid under Condition of Faults on Distribution Line

    Science.gov (United States)

    Malla, S. G.; Bhende, C. N.

    2014-10-01

    The behavior of stand-alone microgrid is analyzed under the condition of faults on distribution feeders. During fault since battery is not able to maintain dc-link voltage within limit, the resistive dump load control is presented to do so. An inverter control is proposed to maintain balanced voltages at PCC under the unbalanced load condition and to reduce voltage unbalance factor (VUF) at load points. The proposed inverter control also has facility to protect itself from high fault current. Existing maximum power point tracker (MPPT) algorithm is modified to limit the speed of generator during fault. Extensive simulation results using MATLAB/SIMULINK established that the performance of the controllers is quite satisfactory under different fault conditions as well as unbalanced load conditions.

  12. Cost estimation of a standalone photovoltaic power system in remote areas of Sarawak, Malaysia

    International Nuclear Information System (INIS)

    Jakhrani, A.Q.; Othman, A.K.; Rigit, A.R.H.; Samo, S.R.

    2012-01-01

    This paper aims to estimate the anticipated costs incurred from a standalone solar photovoltaic power system for the supply of electricity to the rural community in Sarawak, Malaysia. The life cycle cost analysis with net present value technique was employed for the evaluation of cost system. It was found that purchasing of solar photovoltaic components and the system installation cost will contribute 63% of the total investment and future anticipated costs will add to the remaining. Recurring cost will make 25% and components replacements 75% of future anticipated costs. It was discovered that the power generated from the solar photovoltaic system would be 38 times more expensive than electricity produced from the conventional sources. However, its installation in remote areas could be favourable where the grid-connected power supply is not accessible. (author)

  13. Standalone Mobile Application for Shipping Services Based on Geographic Information System and A-Star Algorithm

    Science.gov (United States)

    Gunawan, D.; Marzuki, I.; Candra, A.

    2018-03-01

    Geographic Information Systems (GIS) plays an essential role in shipping service related application. By utilizing GIS, the courier can find the route to deliver goods for its customer. This research proposes a standalone mobile application to provide the shortest route to the destinations by utilizing geographic information systems with A-Star algorithm. This application is intended to be used although the area has no Internet network available. The developed application can handle several drop off points then calculates the shortest route that passes through all the drop off points. According to the conducted testing, the number of drop off points that can be calculated is influenced by the specification of the smartphone. More destinations require more smartphone resources and time to process.

  14. Solar pv fed stand-alone excitation system of a synchronous machine for reactive power generation

    Science.gov (United States)

    Sudhakar, N.; Jain, Siddhartha; Jyotheeswara Reddy, K.

    2017-11-01

    This paper presents a model of a stand-alone solar energy conversion system based on synchronous machine working as a synchronous condenser in overexcited state. The proposed model consists of a Synchronous Condenser, a DC/DC boost converter whose output is fed to the field of the SC. The boost converter is supplied by the modelled solar panel and a day time variable irradiance is fed to the panel during the simulation time. The model also has one alternate source of rechargeable batteries for the time when irradiance falls below a threshold value. Also the excess power produced when there is ample irradiance is divided in two parts and one is fed to the boost converter while other is utilized to recharge the batteries. A simulation is done in MATLAB-SIMULINK and the obtained results show the utility of such modelling for supplying reactive power is feasible.

  15. Use of small stand-alone Internet nodes as a distributed control system

    Science.gov (United States)

    Goodwin, Robert W.; Kucera, Michael J.; Shea, Michael F.

    1994-12-01

    For several years, the standard model for accelerator control systems has been workstation consoles connected to VME local stations by a Local Area Network with analog and digital data being accessed via a field bus to custom I/O interface electronics. Commercially available hardware has now made it possible to implement a small stand-alone data acquisition station that combines the LAN connection, the computer, and the analog and digital I/O interface on a single board. This eliminates the complexity of a field bus and the associated proprietary I/O hardware. A minimum control system is one data acquisition station and a Macintosh or workstation console, both connected to the network; larger systems have more consoles and nodes. An implementation of this architecture is described along with performance and operational experience.

  16. Stand-Alone Photovoltaic System Operation with Energy Management and Fault Tolerant

    International Nuclear Information System (INIS)

    Jmashidpour, Ehsan; Poure, Philippe; Gholipour, E.; Saadate, Shahrokh

    2017-01-01

    This paper presents a stand-alone photovoltaic (PV) system with a fault tolerant operation capability. An energy management method is provided to keep the balance between produced and consumed energy instantaneously. As the storage element, an Ultra-Capacitor (UC) pack is used for facing high frequency variation of the load/source, and batteries are in charge of slow load /source variations. A Maximum Power Point Tracking (MPPT) algorithm is applied to control the boost converter of the PV source to achieve the maximum power. In order to improve the micro-grid service continuity and reliability, a fast fault diagnosis method based on the converter current shape for PV source is applied. Finally, the validity of the proposed energy management and the fault diagnosis method is confirmed by the simulation and experimental results. (author)

  17. Power quality improvement of a stand-alone power system subjected to various disturbances

    Science.gov (United States)

    Lone, Shameem Ahmad; Mufti, Mairaj Ud-Din

    In wind-diesel stand-alone power systems, the disturbances like random nature of wind power, turbulent wind, sudden changes in load demand and the wind park disconnection effect continuously the system voltage and frequency. The satisfactory operation of such a system is not an easy task and the control design has to take in to account all these subtleties. For maintaining the power quality, generally, a short-term energy storage device is used. In this paper, the performance of a wind-diesel system associated with a superconducting magnetic energy storage (SMES) system is studied. The effect of installing SMES at wind park bus/load bus, on the system performance is investigated. To control the exchange of real and reactive powers between the SMES unit and the wind-diesel system, a control strategy based on fuzzy logic is proposed. The dynamic models of the hybrid power system for most common scenarios are developed and the results presented.

  18. JAERI Fuel Cleanup System (J-FCU) stand-alone tritium test at the TSTA

    International Nuclear Information System (INIS)

    Konishi, Satoshi; Hayashi, Takumi; Inoue, Masahiko

    1993-03-01

    JAERI designed, fabricated, and installed the JAERI Fuel Cleanup System (J-FCU) as a subsystem of simulated fusion fuel loop at the TSTA. The main function of the J-FCU is to purify and to recover hydrogen isotopes from simulated plasma exhaust while exhausting tritium free impurities. After a lot of deuterium tests, a first tritium test of the J-FCU was performed with one gram of tritium at the TSTA on June 1991. Main purpose of this test was to evaluate the total integrity and function of the J-FCU system with a DT mixture. Through this test, the J-FCU was operated well and its function with tritium was demonstrated. This report describes the detail test results of the J-FCU first tritium test and discuss its functions by stand-alone mode. Residual tritium inventory of the J-FCU system was also discussed. (author)

  19. System Simulation by Recursive Feedback: Coupling a Set of Stand-Alone Subsystem Simulations

    Science.gov (United States)

    Nixon, D. D.

    2001-01-01

    Conventional construction of digital dynamic system simulations often involves collecting differential equations that model each subsystem, arran g them to a standard form, and obtaining their numerical gin solution as a single coupled, total-system simultaneous set. Simulation by numerical coupling of independent stand-alone subsimulations is a fundamentally different approach that is attractive because, among other things, the architecture naturally facilitates high fidelity, broad scope, and discipline independence. Recursive feedback is defined and discussed as a candidate approach to multidiscipline dynamic system simulation by numerical coupling of self-contained, single-discipline subsystem simulations. A satellite motion example containing three subsystems (orbit dynamics, attitude dynamics, and aerodynamics) has been defined and constructed using this approach. Conventional solution methods are used in the subsystem simulations. Distributed and centralized implementations of coupling have been considered. Numerical results are evaluated by direct comparison with a standard total-system, simultaneous-solution approach.

  20. Standalone BISON Fuel Performance Results for Watts Bar Unit 1, Cycles 1-3

    Energy Technology Data Exchange (ETDEWEB)

    Clarno, Kevin T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pawlowski, Roger [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stimpson, Shane [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Powers, Jeffrey [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-03-07

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) is moving forward with more complex multiphysics simulations and increased focus on incorporating fuel performance analysis methods. The coupled neutronics/thermal-hydraulics capabilities within the Virtual Environment for Reactor Applications Core Simulator (VERA-CS) have become relatively stable, and major advances have been made in analysis efforts, including the simulation of twelve cycles of Watts Bar Nuclear Unit 1 (WBN1) operation. While this is a major achievement, the VERA-CS approaches for treating fuel pin heat transfer have well-known limitations that could be eliminated through better integration with the BISON fuel performance code. Several approaches are being implemented to consider fuel performance, including a more direct multiway coupling with Tiamat, as well as a more loosely coupled one-way approach with standalone BISON cases. Fuel performance typically undergoes an independent analysis using a standalone fuel performance code with manually specified input defined from an independent core simulator solution or set of assumptions. This report summarizes the improvements made since the initial milestone to execute BISON from VERA-CS output. Many of these improvements were prompted through tighter collaboration with the BISON development team at Idaho National Laboratory (INL). A brief description of WBN1 and some of the VERA-CS data used to simulate it are presented. Data from a small mesh sensitivity study are shown, which helps justify the mesh parameters used in this work. The multi-cycle results are presented, followed by the results for the first three cycles of WBN1 operation, particularly the parameters of interest to pellet-clad interaction (PCI) screening (fuel-clad gap closure, maximum centerline fuel temperature, maximum/minimum clad hoop stress, and cumulative damage index). Once the mechanics of this capability are functioning, future work will target cycles with

  1. Optimal expansion planning of stand-alone systems with stochastic simulations

    Energy Technology Data Exchange (ETDEWEB)

    Hoese, Alejandro [Instituto de Energia Electrica (IEE), Universidad Nacional de San Juan, (Argentina)

    1997-12-31

    Stand-alone systems in the range of 1 kW - 10 MW are taking relevance in the new (global) liberal concept of energy market. State and private investors are becoming increasingly attention on the use of renewable for these systems, but it must be shown that these non-conventional solutions are competitive with the established conventional ones. The high investment costs and the technical and economic uncertainties coupled with the use of time-dependent energy sources are the mainly inhibiting factors for the decision agents to choose these systems instead of conventional ones. In the paper a new model for optimal expansion planning of hybrid stand-alone generating systems under consideration of uncertainties is presented. This model is at present in {sup d}evelopment state{sup .} Results already obtained in the first steps of this research are promising and some of them are here presented. [Espanol] Los sistemas autocontenidos en el rango de 1 Kw a 10 MW estan tomando importancia en el nuevo (global) concepto liberal del mercado de la energia. Inversionistas privados y del Estado estan poniendo mayor atencion en el uso de energias renovables para estos sistemas, pero debe mostrarse que estas soluciones no-convencionales son competitivas con las convencionales establecidas. Los altos costos de inversion y las incertidumbres tecnicas y economicas aunadamente con el uso de fuentes de energia dependientes del tiempo son los principales factores inhibidores de los factores de decision para escoger estos sistemas en lugar de los convencionales. En este articulo se presenta un nuevo modelo de planeacion de expansion optima de sistemas hibridos autocontenidos de generacion electrica bajo la consideracion de incertidumbres. Este modelo esta actualmente en {sup e}stado de desarrollo{sup .} Los resultados ya obtenidos en las primeras etapas de esta investigacion son prometedores y se presentan algunos de ellos.

  2. Robust Frequency and Voltage Stability Control Strategy for Standalone AC/DC Hybrid Microgrid

    Directory of Open Access Journals (Sweden)

    Furqan Asghar

    2017-05-01

    Full Text Available The microgrid (MG concept is attracting considerable attention as a solution to energy deficiencies, especially in remote areas, but the intermittent nature of renewable sources and varying loads cause many control problems and thereby affect the quality of power within a microgrid operating in standalone mode. This might cause large frequency and voltage deviations in the system due to unpredictable output power fluctuations. Furthermore, without any main grid support, it is more complex to control and manage the system. In past, droop control and various other coordination control strategies have been presented to stabilize the microgrid frequency and voltages, but in order to utilize the available resources up to their maximum capacity in a positive way, new and robust control mechanisms are required. In this paper, a standalone microgrid is presented, which integrates renewable energy-based distributed generations and local loads. A fuzzy logic-based intelligent control technique is proposed to maintain the frequency and DC (direct current-link voltage stability for sudden changes in load or generation power. Also from a frequency control perspective, a battery energy storage system (BESS is suggested as a replacement for a synchronous generator to stabilize the nominal system frequency as a synchronous generator is unable to operate at its maximum efficiency while being controlled for stabilization purposes. Likewise, a super capacitor (SC and BESS is used to stabilize DC bus voltages even though maximum possible energy is being extracted from renewable generated sources using maximum power point tracking. This newly proposed control method proves to be effective by reducing transient time, minimizing the frequency deviations, maintaining voltages even though maximum power point tracking is working and preventing generators from exceeding their power ratings during disturbances. However, due to the BESS limited capacity, load switching

  3. Diagnostic value of the stand-alone synthetic image in digital breast tomosynthesis examinations.

    Science.gov (United States)

    Garayoa, Julia; Chevalier, Margarita; Castillo, Maria; Mahillo-Fernández, Ignacio; Amallal El Ouahabi, Najim; Estrada, Carmen; Tejerina, Alejandro; Benitez, Olivia; Valverde, Julio

    2018-02-01

    To demonstrate the non-inferiority of synthetic image (SI) mammography versus full-field digital mammography (FFDM) in breast tomosynthesis (DBT) examinations. An observational, retrospective, single-centre, multireader blinded study was performed, using 2384 images to directly compare SI and FFDM based on Breast Imaging Reporting and Data System (BIRADS) categorisation and visibility of radiological findings. Readers had no access to digital breast tomosynthesis slices. Multiple reader, multiple case (MRMC) receiver operating characteristic (ROC) methodology was used to compare the diagnostic performance of SI and FFDM images. The kappa statistic was used to estimate the inter-reader and intra-reader reliability. The area under the ROC curves (AUC) reveals the non-inferiority of SI versus FFDM based on BIRADS categorisation [difference between AUC (ΔAUC), -0.014] and lesion visibility (ΔAUC, -0.001) but the differences were not statistically significant (p=0.282 for BIRADS; p=0.961 for lesion visibility). On average, 77.4% of malignant lesions were detected with SI versus 76.5% with FFDM. Sensitivity and specificity of SI are superior to FFDM for malignant lesions scored as BIRADS 5 and breasts categorised as BIRADS 1. SI is not inferior to FFDM when DBT slices are not available during image reading. SI can replace FFDM, reducing the dose by 45%. • Stand-alone SI demonstrated performance not inferior for lesion visibility as compared to FFDM. • Stand-alone SI demonstrated performance not inferior for lesion BIRADS categorisation as compared to FFDM. • Synthetic images provide important dose savings in breast tomosynthesis examinations.

  4. Energy management system for stand-alone diesel-wind-biomass microgrid with energy storage system

    International Nuclear Information System (INIS)

    Wang, Chengshan; Liu, Yixin; Li, Xialin; Guo, Li; Qiao, Lei; Lu, Hai

    2016-01-01

    An energy management system for stand-alone microgrid composed of diesel generators, wind turbine generator, biomass generator and an ESS (energy storage system) is proposed in this paper. Different operation objectives are achieved by a hierarchical control structure with different time scales. Firstly, the optimal schedules of the diesel generators, wind turbine generator, biomass generator and ESS are determined fifteen minutes ahead according to the super short-term forecast of load and wind speed in the optimal scheduling layer. Comprehensive analysis which takes the uncertainty of load and wind speed into account is conducted in this layer to minimize the operation cost of the system and ensure a desirable range of the state of charge of the ESS. Secondly, the operation points of each unit are regulated dynamically to guarantee real-time power balance and safety range of diesel generation in the real-time control layer, based on which the response capability when suffering significant forecast deviation and other emergency issues, e.g. sudden load-up can be improved. Finally, the effectiveness of the proposed energy management strategy is verified on an RT-Lab based real-time simulation platform, and the economic performances with different types of ESS are analyzed as well. - Highlights: • A hierarchical control strategy is proposed for a stand-alone microgrid. • The uncertainties of load and wind speed have been considered. • Better economic performance and high reliability of the system can be achieved. • The influences of different energy storage systems have been analyzed.

  5. A Meta-Analytic Review of Stand-Alone Interventions to Improve Body Image.

    Directory of Open Access Journals (Sweden)

    Jessica M Alleva

    Full Text Available Numerous stand-alone interventions to improve body image have been developed. The present review used meta-analysis to estimate the effectiveness of such interventions, and to identify the specific change techniques that lead to improvement in body image.The inclusion criteria were that (a the intervention was stand-alone (i.e., solely focused on improving body image, (b a control group was used, (c participants were randomly assigned to conditions, and (d at least one pretest and one posttest measure of body image was taken. Effect sizes were meta-analysed and moderator analyses were conducted. A taxonomy of 48 change techniques used in interventions targeted at body image was developed; all interventions were coded using this taxonomy.The literature search identified 62 tests of interventions (N = 3,846. Interventions produced a small-to-medium improvement in body image (d+ = 0.38, a small-to-medium reduction in beauty ideal internalisation (d+ = -0.37, and a large reduction in social comparison tendencies (d+ = -0.72. However, the effect size for body image was inflated by bias both within and across studies, and was reliable but of small magnitude once corrections for bias were applied. Effect sizes for the other outcomes were no longer reliable once corrections for bias were applied. Several features of the sample, intervention, and methodology moderated intervention effects. Twelve change techniques were associated with improvements in body image, and three techniques were contra-indicated.The findings show that interventions engender only small improvements in body image, and underline the need for large-scale, high-quality trials in this area. The review identifies effective techniques that could be deployed in future interventions.

  6. Optimal expansion planning of stand-alone systems with stochastic simulations

    Energy Technology Data Exchange (ETDEWEB)

    Hoese, Alejandro [Instituto de Energia Electrica (IEE), Universidad Nacional de San Juan, (Argentina)

    1998-12-31

    Stand-alone systems in the range of 1 kW - 10 MW are taking relevance in the new (global) liberal concept of energy market. State and private investors are becoming increasingly attention on the use of renewable for these systems, but it must be shown that these non-conventional solutions are competitive with the established conventional ones. The high investment costs and the technical and economic uncertainties coupled with the use of time-dependent energy sources are the mainly inhibiting factors for the decision agents to choose these systems instead of conventional ones. In the paper a new model for optimal expansion planning of hybrid stand-alone generating systems under consideration of uncertainties is presented. This model is at present in {sup d}evelopment state{sup .} Results already obtained in the first steps of this research are promising and some of them are here presented. [Espanol] Los sistemas autocontenidos en el rango de 1 Kw a 10 MW estan tomando importancia en el nuevo (global) concepto liberal del mercado de la energia. Inversionistas privados y del Estado estan poniendo mayor atencion en el uso de energias renovables para estos sistemas, pero debe mostrarse que estas soluciones no-convencionales son competitivas con las convencionales establecidas. Los altos costos de inversion y las incertidumbres tecnicas y economicas aunadamente con el uso de fuentes de energia dependientes del tiempo son los principales factores inhibidores de los factores de decision para escoger estos sistemas en lugar de los convencionales. En este articulo se presenta un nuevo modelo de planeacion de expansion optima de sistemas hibridos autocontenidos de generacion electrica bajo la consideracion de incertidumbres. Este modelo esta actualmente en {sup e}stado de desarrollo{sup .} Los resultados ya obtenidos en las primeras etapas de esta investigacion son prometedores y se presentan algunos de ellos.

  7. Lockout/Tagout for FODs & RLMs Self-Study 30140

    Energy Technology Data Exchange (ETDEWEB)

    Singledecker, Amalia [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-09

    Lockout/tagout (LO/TO) is used to disable machinery or equipment and to control potentially hazardous energy while service or maintenance is being performed. This course, Lockout/Tagout for FODs & RLMs Self-Study (30140), is designed to introduce facility operations directors (FODs) and responsible line managers (RLMs) to changes in the Los Alamos National Laboratory (LANL) procedure for the lockout and tagout of hazardous energy.

  8. 49 CFR 1109.4 - Mandatory mediation in rate cases to be considered under the stand-alone cost methodology.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Mandatory mediation in rate cases to be considered... § 1109.4 Mandatory mediation in rate cases to be considered under the stand-alone cost methodology. (a) A... methodology must engage in non-binding mediation of its dispute with the railroad upon filing a formal...

  9. An improved synchronous reference frame phase-locked loop for stand-alone variable speed constant frequency power generation systems

    DEFF Research Database (Denmark)

    Liu, Yi; Xu, Wei; Ke, Longzhang

    2017-01-01

    The phase-locked loop (PLL) based on conventional synchronous reference frame, i.e. dqPLL, is usually employed in grid-connected variable speed constant frequency (VSCF) power generation systems (PGSs). However, the voltage amplitude drop of stand-alone PGSs is often greater than that of the grid...

  10. Analyzing grid extension and stand-alone photovoltaic systems for the cost-effective electrification of Kenya

    NARCIS (Netherlands)

    Zeyringer, Marianne; Pachauri, Shonali; Schmid, Erwin; Schmidt, Johannes; Worrell, Ernst|info:eu-repo/dai/nl/106856715; Morawetz, Ulrich B.

    2015-01-01

    The declaration of 2014-2024 as the Decade of Sustainable Energy for All has catalyzed actions towards achieving universal electricity access. The high costs of building electric infrastructure are a major impediment to improved access, making stand-alone photovoltaic (PV) systems an attractive

  11. Individualized choice in prenatal diagnosis : the impact of karyotyping and standalone rapid aneuploidy detection on quality of life

    NARCIS (Netherlands)

    Boormans, E. M. A.; Birnie, E.; Oepkes, D.; Boekkooi, P. F.; Bonsel, G. J.; van Lith, J. M. M.

    2010-01-01

    Objective To assess the reasons and perceptions of women who are offered a choice between karyotyping and standalone rapid aneuploidy detection (RAD) and to compare the impact of both tests on anxiety and health-related quality of life Methods In this prospective comparative study, women undergoing

  12. Stand-Alone Ethics, Social Responsibility, and Sustainability Course Requirements: A Snapshot from Australia and New Zealand

    Science.gov (United States)

    Rundle-Thiele, Sharyn R.; Wymer, Walter

    2010-01-01

    This article analyzes the extent to which Australian and New Zealand marketing educators use dedicated or stand-alone courses to equip students with alternative views of business. A census of marketing programs in degree-granting universities was conducted. Program brochures were obtained via the Internet and were content analyzed. This study…

  13. A New Vector Control of Brushless Doubly-Fed Inductor Generator With Transient Current Compensation for Stand-Alone Power Generation Applications

    DEFF Research Database (Denmark)

    Liu, Yi; Xu, Wei; Yu, Kailiang

    2018-01-01

    The stand-alone brushless doubly-fed induction generator (BDFIG) with the conventional control strategies suffers heavily from poor dynamic performance especially under heavy load disturbance. This paper presents a new vector control strategy of BDFIG for stand-alone power generation applications...... control strategies, and the results verify the satisfactory dynamic performance of the proposed strategy....

  14. New control strategy of stand-alone brushless doubly-fed induction generator for supplying unbalanced loads in ship shaft power generation system

    DEFF Research Database (Denmark)

    Liu, Yi; Xu, Wei; Xiong, Fei

    2017-01-01

    The ship shaft power generation system based on a stand-alone brushless doubly-fed induction generator (BDFIG) have demonstrated excellent saving-energy performance. This paper presents a new control scheme of the stand-alone BDFIG for supplying unbalanced loads in the ship shaft power generation...

  15. Language in use intermediate : self-study workbook

    CERN Document Server

    Doff, Adrian

    1994-01-01

    Each of the four levels comprises about 80 hours of class work, with additional time for the self-study work. The Teacher's Book contains all the pages from the Classroom Book, with interleaved teaching notes including optional activities to cater for different abilities. There is a video to accompany the Beginner, Pre-intermediate and Intermediate levels. Each video contains eight stimulating and entertaining short programmes, as well as a booklet of photocopiable activities. Free test material is available in booklet and web format for Beginner and Pre-intermediate levels. Visit www.cambridge.org/elt/liu or contact your local Cambridge University Press representative.

  16. Exploring oncology nurses' grief: A self-study

    Directory of Open Access Journals (Sweden)

    Lisa C Barbour

    2016-01-01

    Full Text Available Oncology nursing, like many other nursing fields, often provides nurses with the opportunity to get to know their patients and their families well. This familiarity allows oncology nurses to show a level of compassion and empathy that is often helpful to the patient and their family during their struggle with cancer. However, this familiarity can also lead to a profound sense of grief if the patient loses that struggle. This self-study provided me the opportunity to systematically explore my own experience with grief as an oncology nurse, helping me to identify specific stressors and also sources of stress release.

  17. Multi-objective analytical model for optimal sizing of stand-alone photovoltaic water pumping systems

    International Nuclear Information System (INIS)

    Olcan, Ceyda

    2015-01-01

    Highlights: • An analytical optimal sizing model is proposed for PV water pumping systems. • The objectives are chosen as deficiency of power supply and life-cycle costs. • The crop water requirements are estimated for a citrus tree yard in Antalya. • The optimal tilt angles are calculated for fixed, seasonal and monthly changes. • The sizing results showed the validity of the proposed analytical model. - Abstract: Stand-alone photovoltaic (PV) water pumping systems effectively use solar energy for irrigation purposes in remote areas. However the random variability and unpredictability of solar energy makes difficult the penetration of PV implementations and complicate the system design. An optimal sizing of these systems proves to be essential. This paper recommends a techno-economic optimization model to determine optimally the capacity of the components of PV water pumping system using a water storage tank. The proposed model is developed regarding the reliability and cost indicators, which are the deficiency of power supply probability and life-cycle costs, respectively. The novelty is that the proposed optimization model is analytically defined for two-objectives and it is able to find a compromise solution. The sizing of a stand-alone PV water pumping system comprises a detailed analysis of crop water requirements and optimal tilt angles. Besides the necessity of long solar radiation and temperature time series, the accurate forecasts of water supply needs have to be determined. The calculation of the optimal tilt angle for yearly, seasonally and monthly frequencies results in higher system efficiency. It is, therefore, suggested to change regularly the tilt angle in order to maximize solar energy output. The proposed optimal sizing model incorporates all these improvements and can accomplish a comprehensive optimization of PV water pumping systems. A case study is conducted considering the irrigation of citrus trees yard located in Antalya, Turkey

  18. Five-year durability of stand-alone interspinous process decompression for lumbar spinal stenosis

    Directory of Open Access Journals (Sweden)

    Nunley PD

    2017-09-01

    Full Text Available Pierce D Nunley,1 Vikas V Patel,2 Douglas G Orndorff,3 William F Lavelle,4 Jon E Block,5 Fred H Geisler6 1Spine Institute of Louisiana, Shreveport, LA, 2The Spine Center, University of Colorado Hospital, Denver, CO, 3Spine Colorado, Mercy Regional Hospital, Durango, CO, 4Upstate Bone and Joint Center, East Syracuse, NY, 5Independent Consultant, San Francisco, CA, 6Independent Consultant, Chicago, IL, USA Background: Lumbar spinal stenosis is the most common indication for spine surgery in older adults. Interspinous process decompression (IPD using a stand-alone spacer that functions as an extension blocker offers a minimally invasive treatment option for intermittent neurogenic claudication associated with spinal stenosis.Methods: This study evaluated the 5-year clinical outcomes for IPD (Superion® from a randomized controlled US Food and Drug Administration (FDA noninferiority trial. Outcomes included Zurich Claudication Questionnaire (ZCQ symptom severity (ss, physical function (pf, and patient satisfaction (ps subdomains, leg and back pain visual analog scale (VAS, and Oswestry Disability Index (ODI.Results: At 5 years, 84% of patients (74 of 88 demonstrated clinical success on at least two of three ZCQ domains. Individual ZCQ domain success rates were 75% (66 of 88, 81% (71 of 88, and 90% (79 of 88 for ZCQss, ZCQpf, and ZCQps, respectively. Leg and back pain success rates were 80% (68 of 85 and 65% (55 of 85, respectively, and the success rate for ODI was 65% (57 of 88. Percentage improvements over baseline were 42%, 39%, 75%, 66%, and 58% for ZCQss, ZCQpf, leg and back pain VAS, and ODI, respectively (all P<0.001. Within-group effect sizes were classified as very large for four of five clinical outcomes (ie, >1.0; all P<0.0001. Seventy-five percent of IPD patients were free from reoperation, revision, or supplemental fixation at their index level at 5 years.Conclusion: After 5 years of follow-up, IPD with a stand-alone spacer provides

  19. Addressing the challenges of standalone multi-core simulations in molecular dynamics

    Science.gov (United States)

    Ocaya, R. O.; Terblans, J. J.

    2017-07-01

    Computational modelling in material science involves mathematical abstractions of force fields between particles with the aim to postulate, develop and understand materials by simulation. The aggregated pairwise interactions of the material's particles lead to a deduction of its macroscopic behaviours. For practically meaningful macroscopic scales, a large amount of data are generated, leading to vast execution times. Simulation times of hours, days or weeks for moderately sized problems are not uncommon. The reduction of simulation times, improved result accuracy and the associated software and hardware engineering challenges are the main motivations for many of the ongoing researches in the computational sciences. This contribution is concerned mainly with simulations that can be done on a "standalone" computer based on Message Passing Interfaces (MPI), parallel code running on hardware platforms with wide specifications, such as single/multi- processor, multi-core machines with minimal reconfiguration for upward scaling of computational power. The widely available, documented and standardized MPI library provides this functionality through the MPI_Comm_size (), MPI_Comm_rank () and MPI_Reduce () functions. A survey of the literature shows that relatively little is written with respect to the efficient extraction of the inherent computational power in a cluster. In this work, we discuss the main avenues available to tap into this extra power without compromising computational accuracy. We also present methods to overcome the high inertia encountered in single-node-based computational molecular dynamics. We begin by surveying the current state of the art and discuss what it takes to achieve parallelism, efficiency and enhanced computational accuracy through program threads and message passing interfaces. Several code illustrations are given. The pros and cons of writing raw code as opposed to using heuristic, third-party code are also discussed. The growing trend

  20. Efficiency of hydrogen gas production in a stand-alone solar hydrogen system

    International Nuclear Information System (INIS)

    Singh, K.; Tamakloe, R.Y.

    2003-01-01

    Many photovoltaic systems operate in a decentralised electricity producing system, or stand-alone mode and the total energy demand is met by the output of the photovoltaic array. The output of the photovoltaic system fluctuates and is unpredictable for many applications making some forms of energy storage system necessary. The role of storage medium is to store the excess energy produced by the photovoltaic arry, to absorb momentary power peaks and to supply energy during sunless periods. One of the storage modes is the use of electrochemical techniques, with batteries and water electrolysis as the most important examples. The present study includes three main parts: the first one is the hydrogen production form the electrolysis of water depending on the DC output current of the photovoltaic (PV) energy source and the charging of the battery. The second part presents the influence of various parameters on the efficiency of hydrogen gas production. The final part includes simulation studies with focus on solar hydrogen efficiency under the influence of various physical and chemical parameters. For a 50W panel-battery-electrolyser system, the dependence of volume of hydrogen gas on voltage, current and power yielded a maximum efficiency of 13.6% (author)

  1. The Method of a Standalone Functional Verifying Operability of Sonar Control Systems

    Directory of Open Access Journals (Sweden)

    A. A. Sotnikov

    2014-01-01

    Full Text Available This article describes a method of standalone verifying sonar control system, which is based on functional checking of control system operability.The main features of realized method are a development of the valid mathematic model for simulation of sonar signals at the point of hydroacoustic antenna, a valid representation of the sonar control system modes as a discrete Markov model, providing functional object verification in real time mode.Some ways are proposed to control computational complexity in case of insufficient computing resources of the simulation equipment, namely the way of model functionality reduction and the way of adequacy reduction.Experiments were made using testing equipment, which was developed by department of Research Institute of Information Control System at Bauman Moscow State Technical University to verify technical validity of industrial sonar complexes.On-board software was artificially changed to create malfunctions in functionality of sonar control systems during the verifying process in order to estimate verifying system performances.The method efficiency was proved by the theory and experiment results in comparison with the basic methodology of verifying technical systems.This method could be also used in debugging of on-board software of sonar complexes and in development of new promising algorithms of sonar signal processing.

  2. Control of a Stand-Alone Variable Speed Wind Energy Supply System †

    Directory of Open Access Journals (Sweden)

    Mohamed M. Hamada

    2013-04-01

    Full Text Available This paper presents a simple control strategy for the operation of a variable speed stand-alone wind turbine with a permanent magnet synchronous generator (PMSG. The PMSG is connected to a three phase resistive load through a switch mode rectifier and a voltage source inverter. Control of the generator side converter is used to achieve maximum power extraction from the available wind power. Control of the DC-DC bidirectional buck-boost converter, which is connected between batteries bank and DC-link voltage, is used to maintain the DC-link voltage at a constant value. It is also used to make the batteries bank stores the surplus of wind energy and supplies this energy to the load during a wind power shortage. The load side voltage source inverter uses a relatively complex vector control scheme to control the output load voltage in terms of amplitude and frequency. The control strategy works under wind speed variation as well as with variable load. Extensive simulation results have been performed using MATLAB/SIMULINK.

  3. An Improved Method for Sizing Standalone Photovoltaic Systems Using Generalized Regression Neural Network

    Directory of Open Access Journals (Sweden)

    Tamer Khatib

    2014-01-01

    Full Text Available In this research an improved approach for sizing standalone PV system (SAPV is presented. This work is an improved work developed previously by the authors. The previous work is based on the analytical method which faced some concerns regarding the difficulty of finding the model’s coefficients. Therefore, the proposed approach in this research is based on a combination of an analytical method and a machine learning approach for a generalized artificial neural network (GRNN. The GRNN assists to predict the optimal size of a PV system using the geographical coordinates of the targeted site instead of using mathematical formulas. Employing the GRNN facilitates the use of a previously developed method by the authors and avoids some of its drawbacks. The approach has been tested using data from five Malaysian sites. According to the results, the proposed method can be efficiently used for SAPV sizing whereas the proposed GRNN based model predicts the sizing curves of the PV system accurately with a prediction error of 0.6%. Moreover, hourly meteorological and load demand data are used in this research in order to consider the uncertainty of the solar energy and the load demand.

  4. Optimal sizing method for constituent elements of stand-alone photovoltaic power systems

    Energy Technology Data Exchange (ETDEWEB)

    Otsuka, Hirotada; Oi, Yoichi [Hokuriku Electric Power Co., Inc. Toyama (Japan)

    1988-12-25

    The purpose of the report was to calculate the optimal volume of constituent elements of stand-alone photovoltaic power systems, based on the distribution of global radiation on an inclined surface (herein-after called flux of solar radiation), which had been previously measured, and the size of load to be supplied. The least power generation cost was calculated, supposing that setting load was 176kWh/month and the loss of load probability (LOLP) was 1%, by using actual amount of solar radiation in May 1985. The cost was divided into two components: one was proportionate to the size of solar cell, and the other was in proportion to the battery volume. And then, the cost of twenty-year operation(TLC) was calculated. The size of array and the battery volume, which minimize the cost, can be determined when TLC is differentiate. Since auxiliary power source is not attached to this system, it is necessary to restrict the load in order to meet the electric power shortage. In case of the cost at construction in 1984, a standard model indicating the least power generation cost is a photovoltaic system with the array size of A=49.0m{sup 2} and the battery volume of Q=568(Ah). 4 refs., 9 figs., 10 tabs.

  5. Battery Storage Technologies for Electrical Applications: Impact in Stand-Alone Photovoltaic Systems

    Directory of Open Access Journals (Sweden)

    Daniel Akinyele

    2017-11-01

    Full Text Available Batteries are promising storage technologies for stationary applications because of their maturity, and the ease with which they are designed and installed compared to other technologies. However, they pose threats to the environment and human health. Several studies have discussed the various battery technologies and applications, but evaluating the environmental impact of batteries in electrical systems remains a gap that requires concerted research efforts. This study first presents an overview of batteries and compares their technical properties such as the cycle life, power and energy densities, efficiencies and the costs. It proposes an optimal battery technology sizing and selection strategy, and then assesses the environmental impact of batteries in a typical renewable energy application by using a stand-alone photovoltaic (PV system as a case study. The greenhouse gas (GHG impact of the batteries is evaluated based on the life cycle emission rate parameter. Results reveal that the battery has a significant impact in the energy system, with a GHG impact of about 36–68% in a 1.5 kW PV system for different locations. The paper discusses new batteries, strategies to minimize battery impact and provides insights into the selection of batteries with improved cycling capacity, higher lifespan and lower cost that can achieve lower environmental impacts for future applications.

  6. [Clinical application of stand-alone MC+PEEK cage in the anterior cervical fusion].

    Science.gov (United States)

    Jiang, Bing; Cao, Yan-Qing; Pan, Hong; Zhu, Cheng-Run; Zhang, Xiao-Jun; Tao, Yue-Feng; Liu, Zhen

    2015-04-01

    To explore the effect of clinical application of stand-alone MC+PEEK cage in anterior cervical fusion. From January 2011 to January 2014,50 patients were treated with the MC+PEEK cage filled with autogenous cancellous illic-bone graft after anterior cervical discectomy. There were 22 patients with cervical spondylosis,26 patients with traumatic cervical disc herniation, 2 patients with cervical instability in these patients. There were 32 males and 18 females, aged from 30 to 79 years old with an average of 53.30 years old. There were 32 patients with single segment, 15 patients with double segments and 3 patients with three segments. Cervical AP and lateral and the flexion-extension X-rays were regularly taken in order to assess the cervical physiological curvature, the graft fusion and internal fixation related complications. Nerve function, clinical effect and bone fusion were respectively evaluated according to Japan Orthopedic Association (JOA), Otani grade and Suk method. All patients were followed up from 6 to 36 months with an average of 20 months. No correlated surgical complications were found and all patients obtained bony fusion with an average time of 4.30 months. JOA score had significantly improvement after surgery (P cervical fusion can obtain satisfactory clinical effect with less operation injury and reduce the complications. It is a better fusion method in anterior cervical fusion.

  7. Performance and Simulation of a Stand-alone Parabolic Trough Solar Thermal Power Plant

    Science.gov (United States)

    Mohammad, S. T.; Al-Kayiem, H. H.; Assadi, M. K.; Gilani, S. I. U. H.; Khlief, A. K.

    2018-05-01

    In this paper, a Simulink® Thermolib Model has been established for simulation performance evaluation of Stand-alone Parabolic Trough Solar Thermal Power Plant in Universiti Teknologi PETRONAS, Malaysia. This paper proposes a design of 1.2 kW parabolic trough power plant. The model is capable to predict temperatures at any system outlet in the plant, as well as the power output produced. The conditions that are taken into account as input to the model are: local solar radiation and ambient temperatures, which have been measured during the year. Other parameters that have been input to the model are the collector’s sizes, location in terms of latitude and altitude. Lastly, the results are presented in graphical manner to describe the analysed variations of various outputs of the solar fields obtained, and help to predict the performance of the plant. The developed model allows an initial evaluation of the viability and technical feasibility of any similar solar thermal power plant.

  8. Graphene-Based Standalone Solar Energy Converter for Water Desalination and Purification.

    Science.gov (United States)

    Yang, Yang; Zhao, Ruiqi; Zhang, Tengfei; Zhao, Kai; Xiao, Peishuang; Ma, Yanfeng; Ajayan, Pulickel M; Shi, Gaoquan; Chen, Yongsheng

    2018-01-23

    Harvesting solar energy for desalination and sewage treatment has been considered as a promising solution to produce clean water. However, state-of-the-art technologies often require optical concentrators and complicated systems with multiple components, leading to poor efficiency and high cost. Here, we demonstrate an extremely simple and standalone solar energy converter consisting of only an as-prepared 3D cross-linked honeycomb graphene foam material without any other supporting components. This simple all-in-one material can act as an ideal solar thermal converter capable of capturing and converting sunlight into heat, which in turn can distill water from various water sources into steam and produce purified water under ambient conditions and low solar flux with very high efficiency. High specific water production rate of 2.6 kg h -1 m -2 g -1 was achieved with near ∼87% under 1 sun intensity and >80% efficiency even under ambient sunlight (solar thermal water purification system for a variety of environmental conditions.

  9. Can aqueous hydrogen peroxide be used as a stand-alone energy source?

    International Nuclear Information System (INIS)

    Disselkamp, Robert S.

    2010-01-01

    A novel electrochemical scheme to convert a stand-alone supply of aqueous hydrogen peroxide into a fuel cell-ready stream of hydrogen gas plus aqueous hydrogen peroxide is described. The electrochemical cell, consisting of a solid base and solid acid electrocatalyst, together with a proton exchange membrane, comprise the system that converts aqueous hydrogen peroxide into separate gas streams of oxygen and hydrogen. Aqueous hydrogen peroxide is contained in the anode compartment only and exists in the region where oxygen gas is formed, whereas the cathode compartment is where hydrogen gas is generated and therefore exists in a reduced state. A near zero theoretical over-potential can be achieved by the choice of basicity and acidity of the electrode materials. The primary cost of the electrochemical cell is electrode construction and the aqueous hydrogen peroxide energy storage compound. Additional research effort is required to experimentally validate the concept and explore the full economic impact should initial studies, based on the design presented here, prove promising. (author)

  10. An intelligent stand-alone ultrasonic device for monitoring local structural damage: implementation and preliminary experiments

    International Nuclear Information System (INIS)

    Pertsch, Alexander; Kim, Jin-Yeon; Wang, Yang; Jacobs, Laurence J

    2011-01-01

    Continuous structural health monitoring has the potential to significantly improve the safety management of aged, in-service civil structures. In particular, monitoring of local damage growth at hot-spot areas can help to prevent disastrous structural failures. Although ultrasonic nondestructive evaluation (NDE) has proved to be effective in monitoring local damage growth, conventional equipment and devices are usually bulky and only suitable for scheduled human inspections. The objective of this research is to harness the latest developments in embedded hardware and wireless communication for developing a stand-alone, compact ultrasonic device. The device is directed at the continuous structural health monitoring of civil structures. Relying on battery power, the device possesses the functionalities of high-speed actuation, sensing, signal processing, and wireless communication. Integrated with contact ultrasonic transducers, the device can generate 1 MHz Rayleigh surface waves in a steel specimen and measure response waves. An envelope detection algorithm based on the Hilbert transform is presented for efficiently determining the peak values of the response signals, from which small surface cracks are successfully identified

  11. A Standalone Solar Photovoltaic Power Generation using Cuk Converter and Single Phase Inverter

    Science.gov (United States)

    Verma, A. K.; Singh, B.; Kaushika, S. C.

    2013-03-01

    In this paper, a standalone solar photovoltaic (SPV) power generating system is designed and modeled using a Cuk dc-dc converter and a single phase voltage source inverter (VSI). In this system, a dc-dc boost converter boosts a low voltage of a PV array to charge a battery at 24 V using a maximum power point tracking control algorithm. To step up a 24 V battery voltage to 360 V dc, a high frequency transformer based isolated dc-dc Cuk converter is used to reduce size, weight and losses. The dc voltage of 360 V is fed to a single phase VSI with unipolar switching to achieve a 230 Vrms, 50 Hz ac. The main objectives of this investigation are on efficiency improvement, reduction in cost, weight and size of the system and to provide an uninterruptible power to remotely located consumers. The complete SPV system is designed and it is modeled in MATLAB/Simulink. The simulated results are presented to demonstrate its satisfactory performance for validating the proposed design and control algorithm.

  12. Approaches for developing a sizing method for stand-alone PV systems with variable demand

    Energy Technology Data Exchange (ETDEWEB)

    Posadillo, R. [Grupo de Investigacion en Energias y Recursos Renovables, Dpto. de Fisica Aplicada, E.P.S., Universidad de Cordoba, Avda. Menendez Pidal s/n, 14004 Cordoba (Spain); Lopez Luque, R. [Grupo de Investigacion de Fisica para las Energias y Recursos Renovables, Dpto. de Fisica Aplicada. Edificio C2 Campus de Rabanales, 14071 Cordoba (Spain)

    2008-05-15

    Accurate sizing is one of the most important aspects to take into consideration when designing a stand-alone photovoltaic system (SAPV). Various methods, which differ in terms of their simplicity or reliability, have been developed for this purpose. Analytical methods, which seek functional relationships between variables of interest to the sizing problem, are one of these approaches. A series of rational considerations are presented in this paper with the aim of shedding light upon the basic principles and results of various sizing methods proposed by different authors. These considerations set the basis for a new analytical method that has been designed for systems with variable monthly energy demands. Following previous approaches, the method proposed is based on the concept of loss of load probability (LLP) - a parameter that is used to characterize system design. The method includes information on the standard deviation of loss of load probability ({sigma}{sub LLP}) and on two new parameters: annual number of system failures (f) and standard deviation of annual number of failures ({sigma}{sub f}). The method proves useful for sizing a PV system in a reliable manner and serves to explain the discrepancies found in the research on systems with LLP<10{sup -2}. We demonstrate that reliability depends not only on the sizing variables and on the distribution function of solar radiation, but on the minimum value as well, which in a given location and with a monthly average clearness index, achieves total solar radiation on the receiver surface. (author)

  13. Stand-alone excitation synchronous wind power generators with power flow management strategy

    Directory of Open Access Journals (Sweden)

    Tzuen-Lih Chern

    2014-09-01

    Full Text Available This study presents a stand-alone excitation synchronous wind power generator (SESWPG with power flow management strategy (PFMS. The rotor speed of the excitation synchronous generator tracks the utility grid frequency by using servo motor tracking technologies. The automatic voltage regulator governs the exciting current of generator to achieve the control goals of stable voltage. When wind power is less than the needs of the consumptive loading, the proposed PFMS increases motor torque to provide a positive power output for the loads, while keeping the generator speed constant. Conversely, during the periods of wind power greater than output loads, the redundant power of generator production is charged to the battery pack and the motor speed remains constant with very low power consumption. The advantage of the proposed SESWPG is that the generator can directly output stable alternating current (AC electricity without using additional DC–AC converters. The operation principles with software simulation for the system are described in detail. Experimental results of a laboratory prototype are shown to verify the feasibility of the system.

  14. Analysis and control of induction generator supplying stand-alone AC loads employing a Matrix Converter

    Directory of Open Access Journals (Sweden)

    Sumedha Mahajan

    2017-04-01

    Full Text Available This paper proposes a Capacitor Excited Induction Generator (CEIG-Matrix Converter (MC system for feeding stand-alone AC loads. The variable output voltage magnitude and frequency from CEIG is converted into a constant voltage magnitude and frequency at the load terminals by controlling MC using Space Vector Modulation (SVM technique. This single-stage MC is turned up as a good alternative for the proposed system against commonly used AC/DC/AC two stage power converters. The configuration and implementation of the closed-loop control scheme employing dSPACE 1103 real time controller have been fully described in the paper. The proposed closed-loop controller regulates the AC load voltage irrespective of changes in the prime mover speed and load. A method for predetermining the steady-state performance of the proposed system has been developed and described with relevant analytical expressions. The effectiveness of the proposed system is exemplified through simulation results for various operating conditions. The proposed control technique is further validated using an experimental setup developed in the laboratory.

  15. Improvement of maximum power point tracking perturb and observe algorithm for a standalone solar photovoltaic system

    International Nuclear Information System (INIS)

    Awan, M.M.A.; Awan, F.G.

    2017-01-01

    Extraction of maximum power from PV (Photovoltaic) cell is necessary to make the PV system efficient. Maximum power can be achieved by operating the system at MPP (Maximum Power Point) (taking the operating point of PV panel to MPP) and for this purpose MPPT (Maximum Power Point Trackers) are used. There are many tracking algorithms/methods used by these trackers which includes incremental conductance, constant voltage method, constant current method, short circuit current method, PAO (Perturb and Observe) method, and open circuit voltage method but PAO is the mostly used algorithm because it is simple and easy to implement. PAO algorithm has some drawbacks, one is low tracking speed under rapid changing weather conditions and second is oscillations of PV systems operating point around MPP. Little improvement is achieved in past papers regarding these issues. In this paper, a new method named 'Decrease and Fix' method is successfully introduced as improvement in PAO algorithm to overcome these issues of tracking speed and oscillations. Decrease and fix method is the first successful attempt with PAO algorithm for stability achievement and speeding up of tracking process in photovoltaic system. Complete standalone photovoltaic system's model with improved perturb and observe algorithm is simulated in MATLAB Simulink. (author)

  16. Design of a reliable and low-cost stand-alone micro hydropower station

    Energy Technology Data Exchange (ETDEWEB)

    Kusakana, K.; Munda, J.L. [Tshwane Univ. of Technology, Pretoria (South Africa)

    2008-07-01

    A stand-alone micro-hydropower station was presented. The plant was comprised of a squirrel cage induction machine coupled to a Kaplan water turbine. Power converters were used to control the variable frequency and voltage outputs of the generator caused by variations in water flow. The hydropower plant was installed a farm in the Kwazulu-Natal region of South Africa, and was designed to provide electricity in relation to the low power demand of users in the region as well as according to the site's hydrology and topology. Load forecasts for the 8 houses using the system were conducted. A generator with a higher output than the average power needed to feed the load was selected in order to ensure load supply during peak demand. The system was designed to shore energy generated during off-peak periods in batteries. An AC-DC-AC converter was used as an interface between the generator and the load in order to ensure voltage and frequency stabilization. Simulations of plant components were conducted to demonstrate output power supply during water flow variations. Results of the modelling study indicated that power converters are needed to stabilize generator outputs. The hydropower design is a cost-effective means of supplying power to low-income households. 10 refs., 2 tabs., 7 figs.

  17. Solar photovoltaic applications seminar: design, installation and operation of small, stand-alone photovoltaic power systems

    Energy Technology Data Exchange (ETDEWEB)

    1980-07-01

    This seminar material was developed primarily to provide solar photovoltaic (PV) applied engineering technology to the Federal community. An introduction to photoconductivity, semiconductors, and solar photovoltaic cells is included along with a demonstration of specific applications and application identification. The seminar details general systems design and incorporates most known information from industry, academia, and Government concerning small solar cell power system design engineering, presented in a practical and applied manner. Solar PV power system applications involve classical direct electrical energy conversion and electric power system analysis and synthesis. Presentations and examples involve a variety of disciplines including structural analysis, electric power and load analysis, reliability, sizing and optimization; and, installation, operation and maintenance. Four specific system designs are demonstrated: water pumping, domestic uses, navigational and aircraft aids, and telecommunications. All of the applications discussed are for small power requirement (under 2 kilowatts), stand-alone systems to be used in remote locations. Also presented are practical lessons gained from currently installed and operating systems, problems at sites and their resolution, a logical progression through each major phase of system acquisition, as well as thorough design reviews for each application.

  18. Use of Super-Capacitor to Enhance Charging Performance of Stand-Alone Solar PV System

    KAUST Repository

    Huang, B. J.

    2011-01-01

    Introduction: The battery charging performance in a stand-alone solar PV system affects the PV system efficiency and the load operating time. The New Energy Center of National Taiwan University has been devoted to the development of a PWM charging technique to continue charging the lead-acid battery after the overcharge point to increase the battery storage capacity by more than 10%. The present study intends to use the super-capacitor to further increase the charge capacity before the overcharge point of the battery. The super-capacitor is connected in parallel to the lead-acid battery. This will reduce the overall charging impedance during the charge and increase the charging current, especially in sunny weather. A system dynamics model of the lead-acid battery and super-capacitor was derived and the control system simulation was carried out to predict the charging performance for various weathers. It shows that the overall battery impedance decreases and charging power increases with increasing solar radiation. An outdoor comparative test for two identical PV systems with and without supercapacitor was carried out. The use of super-capacitor is shown to be able to increase the lead-acid charging capacity by more than 25% at sunny weather and 10% in cloudy weather. © Springer-Verlag Berlin Heidelberg 2011.

  19. AERYN: A simple standalone application for visualizing and enhancing elemental maps

    International Nuclear Information System (INIS)

    Mouchi, Vincent; Crowley, Quentin G.; Ubide, Teresa

    2016-01-01

    Interpretation of high spatial resolution elemental mineral maps can be hindered by high frequency fluctuations, as well as by strong naturally-occurring or analytically-induced variations. We have developed a new standalone program named AERYN (Aspect Enhancement by Removing Yielded Noise) to produce more reliable element distribution maps from previously reduced geochemical data. The program is Matlab-based, designed with a graphic user interface and is capable of rapidly generating elemental maps from data acquired by a range of analytical techniques. A visual interface aids selection of appropriate outlier rejection and drift-correction parameters, thereby facilitating recognition of subtle elemental fluctuations which may otherwise be obscured. Examples of use are provided for quantitative trace element maps acquired using both laser ablation (LA-) ICP-MS and electron probe microanalysis (EPMA) of the cold-water coral Lophelia pertusa. We demonstrate how AERYN allows recognition of high frequency elemental fluctuations, including those which occur perpendicular to the maximum concentration gradient. Such data treatment compliments commonly used processing methods to provide greater flexibility and control in producing elemental maps from micro-analytical techniques. - Highlights: • Matlab-based application to improve visualization of elemental maps. • Capable of detrending when data set shows drift. • Compatible with processed data text files from LA-ICP-MS, EDS and EPMA. • Option to filter geochemical trends to observe high-frequency fluctuations.

  20. On the economics of stand-alone renewable hybrid power plants in remote regions

    International Nuclear Information System (INIS)

    Petrakopoulou, Fontina

    2016-01-01

    Highlights: • Economic evaluation of three renewable hybrid power plants for off-grid operation. • The high electricity cost of remote regions increases the competitiveness of renewable energy. • The proposed plants are economically viable when compared to the existing situation. • The zero direct emissions of the plants constitute an additional advantage of the plants. - Abstract: In recent years ever more examples of regions that have managed to achieve or orientate themselves toward renewable energy sufficiency are emerging. However, actions to create energy autonomy are mainly the result of isolated activities and they are less driven from fully organized movements. In addition, total energy independence without the support of a centralized electrical grid is yet to be achieved. The objectives of this work are to investigate the associated costs of stand-alone renewable hybrid power plants on a Greek island and compare them to the cost of the currently used fossil-fuel-based conventional plant. The plants examined here are designed to fully cover the electricity needs of the island. Islands may face numerous energy problems and rely heavily on foreign and environmentally-harmful fuels. It is shown that the relatively high cost of electricity of such a remote region can increase the competitiveness and promote the wider incorporation of technologies based on renewable energy sources that may, in other cases, seem economically inferior to business-as-usual energy solutions.

  1. MIRNA-DISTILLER: a stand-alone application to compile microRNA data from databases

    Directory of Open Access Journals (Sweden)

    Jessica K. Rieger

    2011-07-01

    Full Text Available MicroRNAs (miRNA are small non-coding RNA molecules of ~22 nucleotides which regulate large numbers of genes by binding to seed sequences at the 3’-UTR of target gene transcripts. The target mRNA is then usually degraded or translation is inhibited, although thus resulting in posttranscriptional down regulation of gene expression at the mRNA and/or protein level. Due to the bioinformatic difficulties in predicting functional miRNA binding sites, several publically available databases have been developed that predict miRNA binding sites based on different algorithms. The parallel use of different databases is currently indispensable, but highly uncomfortable and time consuming, especially when working with numerous genes of interest. We have therefore developed a new stand-alone program, termed MIRNA-DISTILLER, which allows to compile miRNA data for given target genes from public databases. Currently implemented are TargetScan, microCosm, and miRDB, which may be queried independently, pairwise, or together to calculate the respective intersections. Data are stored locally for application of further analysis tools including freely definable biological parameter filters, customized output-lists for both miRNAs and target genes, and various graphical facilities. The software, a data example file and a tutorial are freely available at http://www.ikp-stuttgart.de/content/language1/html/10415.asp

  2. MIRNA-DISTILLER: A Stand-Alone Application to Compile microRNA Data from Databases.

    Science.gov (United States)

    Rieger, Jessica K; Bodan, Denis A; Zanger, Ulrich M

    2011-01-01

    MicroRNAs (miRNA) are small non-coding RNA molecules of ∼22 nucleotides which regulate large numbers of genes by binding to seed sequences at the 3'-untranslated region of target gene transcripts. The target mRNA is then usually degraded or translation is inhibited, although thus resulting in posttranscriptional down regulation of gene expression at the mRNA and/or protein level. Due to the bioinformatic difficulties in predicting functional miRNA binding sites, several publically available databases have been developed that predict miRNA binding sites based on different algorithms. The parallel use of different databases is currently indispensable, but highly uncomfortable and time consuming, especially when working with numerous genes of interest. We have therefore developed a new stand-alone program, termed MIRNA-DISTILLER, which allows to compile miRNA data for given target genes from public databases. Currently implemented are TargetScan, microCosm, and miRDB, which may be queried independently, pairwise, or together to calculate the respective intersections. Data are stored locally for application of further analysis tools including freely definable biological parameter filters, customized output-lists for both miRNAs and target genes, and various graphical facilities. The software, a data example file and a tutorial are freely available at http://www.ikp-stuttgart.de/content/language1/html/10415.asp.

  3. Stand-alone flat-plate photovoltaic power systems: System sizing and life-cycle costing methodology for Federal agencies

    Science.gov (United States)

    Borden, C. S.; Volkmer, K.; Cochrane, E. H.; Lawson, A. C.

    1984-01-01

    A simple methodology to estimate photovoltaic system size and life-cycle costs in stand-alone applications is presented. It is designed to assist engineers at Government agencies in determining the feasibility of using small stand-alone photovoltaic systems to supply ac or dc power to the load. Photovoltaic system design considerations are presented as well as the equations for sizing the flat-plate array and the battery storage to meet the required load. Cost effectiveness of a candidate photovoltaic system is based on comparison with the life-cycle cost of alternative systems. Examples of alternative systems addressed are batteries, diesel generators, the utility grid, and other renewable energy systems.

  4. Design and standalone characterisation of a capacitively coupled HV-CMOS sensor chip for the CLIC vertex detector

    Science.gov (United States)

    Kremastiotis, I.; Ballabriga, R.; Campbell, M.; Dannheim, D.; Fiergolski, A.; Hynds, D.; Kulis, S.; Peric, I.

    2017-09-01

    The concept of capacitive coupling between sensors and readout chips is under study for the vertex detector at the proposed high-energy CLIC electron positron collider. The CLICpix Capacitively Coupled Pixel Detector (C3PD) is an active High-Voltage CMOS sensor, designed to be capacitively coupled to the CLICpix2 readout chip. The chip is implemented in a commercial 180 nm HV-CMOS process and contains a matrix of 128×128 square pixels with 25μm pitch. First prototypes have been produced with a standard resistivity of ~20 Ωcm for the substrate and tested in standalone mode. The results show a rise time of ~20 ns, charge gain of 190 mV/ke- and ~40 e- RMS noise for a power consumption of 4.8μW/pixel. The main design aspects, as well as standalone measurement results, are presented.

  5. Neural Network based Control of SG based Standalone Generating System with Energy Storage for Power Quality Enhancement

    Science.gov (United States)

    Nayar, Priya; Singh, Bhim; Mishra, Sukumar

    2017-08-01

    An artificial intelligence based control algorithm is used in solving power quality problems of a diesel engine driven synchronous generator with automatic voltage regulator and governor based standalone system. A voltage source converter integrated with a battery energy storage system is employed to mitigate the power quality problems. An adaptive neural network based signed regressor control algorithm is used for the estimation of the fundamental component of load currents for control of a standalone system with load leveling as an integral feature. The developed model of the system performs accurately under varying load conditions and provides good dynamic response to the step changes in loads. The real time performance is achieved using MATLAB along with simulink/simpower system toolboxes and results adhere to an IEEE-519 standard for power quality enhancement.

  6. prfectBLAST: a platform-independent portable front end for the command terminal BLAST+ stand-alone suite.

    Science.gov (United States)

    Santiago-Sotelo, Perfecto; Ramirez-Prado, Jorge Humberto

    2012-11-01

    prfectBLAST is a multiplatform graphical user interface (GUI) for the stand-alone BLAST+ suite of applications. It allows researchers to do nucleotide or amino acid sequence similarity searches against public (or user-customized) databases that are locally stored. It does not require any dependencies or installation and can be used from a portable flash drive. prfectBLAST is implemented in Java version 6 (SUN) and runs on all platforms that support Java and for which National Center for Biotechnology Information has made available stand-alone BLAST executables, including MS Windows, Mac OS X, and Linux. It is free and open source software, made available under the GNU General Public License version 3 (GPLv3) and can be downloaded at www.cicy.mx/sitios/jramirez or http://code.google.com/p/prfectblast/.

  7. Modeling, design and analysis of a stand-alone hybrid power generation system using solar/urine

    International Nuclear Information System (INIS)

    Wu, Wei; Zhou, Ya-Yan; Lin, Mu-Hsuan; Hwang, Jenn-Jiang

    2013-01-01

    Highlights: • The stand-alone hybrid power system is presented. • The urine-to-hydrogen processor is proposed. • Scenario analysis of the hybrid power dispatching and the urine/solar demands is investigated. • The design, modeling and optimization of the hybrid power system is addressed by Aspen Plus and Matlab. - Abstract: The urine turned to hydrogen as an energy conversion process is integrated into a stand-alone hybrid (PV/FC/battery) power generation system. The optimization and simulation of a new urine-to-hydrogen processor is evaluated in Aspen Plus environment. In our approach, the PV generator aims to reduce urine consumption and the lithium-ion battery can compensate the power gap due to the fuel processing delay. Based on prescribed patterns of solar irradiation and the daily load demand of a 30-persons classroom, scenario analyses of the hybrid power dispatching and operational feasibility is addressed

  8. Enhancement of a stand-alone photovoltaic system's performance: Reduction of soft and hard shading

    Energy Technology Data Exchange (ETDEWEB)

    Lamont, Lisa A.; El Chaar, Lana [Petroleum Institute, Electrical Engineering Department, P.O. Box 2533, Abu Dhabi (United Arab Emirates)

    2011-04-15

    A stand-alone photovoltaic (PV) system is the most promising solution to supply electric power to meet energy demand in isolated locations. This technology can offer an interesting alternative to other currently existing sources of energy. Due to space constraint in the remote offshore oil and gas industry, a stand-alone system is used for cathodic protection, telemetry and valve control. However in such an environment, dust accumulation and bird droppings have been critical issues to the operation of off-grid solar devices. These factors do not only reduce the available power of the modules but also makes the cost of solar devices ineffective since cleaning, especially on well-head towers, is very expensive due to the location. Hence this paper presents two technical solutions that have shown promising results in reducing the impact of these factors. (author)

  9. Rattling the Cage: Moving beyond Ethical Standards to Ethical Praxis in Self-Study Research

    Science.gov (United States)

    Brandenburg, Robyn; Gervasoni, Ann

    2012-01-01

    The ethical practice underpinning self-study research has been addressed extensively in the literature of self-study of teacher education practices. Less attention has been paid to how researchers deal with ethical tensions and dilemmas when they arise unexpectedly during self-study research. In this article, we examine how the extrapolation and…

  10. Stand-Alone Photovoltaic System Assessment in Warmer Urban Areas in Mexico

    Directory of Open Access Journals (Sweden)

    Alberto-Jesus Perea-Moreno

    2018-01-01

    Full Text Available The aim of this study is to examine the possibility of using a stand-alone photovoltaic system (SAPVS for electricity generation in urban areas in Southern Mexico. In Mexico, an urban area is defined as an area where more than 2500 inhabitants live. Due to constant migration from the countryside to the cities, the number of inhabitants of urban localities has been increasing. Global horizontal irradiation (GHI data were recorded every 10 min during 2014–2016 in Coatzacoalcos in the state of Veracruz located on 18°08′09″ N and 94°27′48″ W. In this study, batteries represented 77% of the total cost, 12 PV panels of 310 W could export 5.41 MWh to the grid, and an inverter with an integrated controller and charger was selected, which decreased the initial cost. The city of Coatzacoalcos was chosen because the average annual temperature is 28°, with an average relative humidity of 75% and an average irradiance of 5.3 kWh/m2/day. An emission factor 0.505 tCO2/MWh of greenhouse gases (GHG were obtained, based on the power system, the reduction of net annual GHG would be 11 tCO2 and a financial revenue of 36.951 × 103 $/tCO2 would be obtained. Financial parameters such as a 36.3% Internal Rate Return (IRR and 3.4 years payback show the financial viability of this investment. SAPVSs in urban areas in Mexico could be a benefit as long as housing has a high consumption of electricity.

  11. Imagery rescripting as a stand-alone treatment for patients with social phobia: a case series.

    Science.gov (United States)

    Frets, Petra G; Kevenaar, Ciska; van der Heiden, Colin

    2014-03-01

    The majority of patients with social phobia reports experiencing negative images, usually linked to memories of earlier aversive social experiences. Several studies have indicated that such negative self-imagery appears to have a causal role in maintaining social phobia, which suggests that interventions aimed at dealing with these images could be beneficial in the treatment of social phobia. One potentially powerful approach is imagery rescripting (IR), a clinical intervention that focuses on changing the meaning and impact of unpleasant memories. In the treatment of social phobia IR was only used as part of a broader cognitive-behavioral treatment package. However, we propose that IR alone might also be an effective treatment for this anxiety disorder. The present study reports an initial evaluation of the application of IR as a stand-alone treatment for six adult outpatients presenting with social phobia. A single case series using an A-B replication across patients design was employed. Following a no-treatment baseline period, IR was delivered weekly and patients were followed up for 3 and 6 months. For all patients, substantial reductions were obtained on all outcome measures at post-treatment, and gains were largely maintained at 6-months follow-up. The generalizability of the effects of IR for social phobia is limited by the small number of patients treated by only one therapist. The results of this preliminary case series suggest that IR as a stand alone treatment is an apparently effective intervention in the treatment of patients with social phobia, and indicate that controlled evaluation of its efficacy might be worthwhile. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Thermal Analysis of the Receiver of a Standalone Pilot Solar Dish–Stirling System

    Directory of Open Access Journals (Sweden)

    Ehsan Gholamalizadeh

    2018-06-01

    Full Text Available Recent developments in solar thermal systems have aroused considerable interest in several countries with high solar potential. One of the most promising solar driven technologies is the solar thermal dish-Stirling system. One of the main issues of the solar dish–Stirling system is thermal losses from its components. The majority of the thermal losses of the system occur through its receiver before the thermal energy is converted to electrical energy by the Stirling engine. The goal of this investigation is to analyze the thermal performance of the receiver of a standalone pilot solar dish–Stirling system installed in Kerman City, Iran, to be used in remote off-grid areas of the Kerman Province. An analytical model was developed to predict the input energy, thermal losses, and thermal efficiency of the receiver. The receiver thermal model was first validated by comparing simulation results to experimental measurements for the EuroDish project. Then, the incident flux intensity intercepted by the receiver aperture, the thermal losses through the receiver (including conduction, convection, and radiation losses, and the power output during daytime hours (average day of each month for a year were predicted. The results showed that the conduction loss was small, while the convection and radiation losses played major roles in the total thermal losses through the receiver. The convection loss is dominant during the early morning and later evening hours, while radiation loss reaches its highest value near midday. Finally, the thermal efficiency of the receiver and the power output for each working hour throughout the year were calculated. The maximum performance of the system occurred at midday in the middle of July, with a predicted power output of 850 W, and a receiver efficiency of about 60%. At this time, a conduction loss of about 266 W, a convection loss of 284 W, and a radiation loss of about 2000 W were estimated.

  13. The Use of Artificial Neural Networks for Forecasting the Electric Demand of Stand-Alone Consumers

    Science.gov (United States)

    Ivanin, O. A.; Direktor, L. B.

    2018-05-01

    The problem of short-term forecasting of electric power demand of stand-alone consumers (small inhabited localities) situated outside centralized power supply areas is considered. The basic approaches to modeling the electric power demand depending on the forecasting time frame and the problems set, as well as the specific features of such modeling, are described. The advantages and disadvantages of the methods used for the short-term forecast of the electric demand are indicated, and difficulties involved in the solution of the problem are outlined. The basic principles of arranging artificial neural networks are set forth; it is also shown that the proposed method is preferable when the input information necessary for prediction is lacking or incomplete. The selection of the parameters that should be included into the list of the input data for modeling the electric power demand of residential areas using artificial neural networks is validated. The structure of a neural network is proposed for solving the problem of modeling the electric power demand of residential areas. The specific features of generation of the training dataset are outlined. The results of test modeling of daily electric demand curves for some settlements of Kamchatka and Yakutia based on known actual electric demand curves are provided. The reliability of the test modeling has been validated. A high value of the deviation of the modeled curve from the reference curve obtained in one of the four reference calculations is explained. The input data and the predicted power demand curves for the rural settlement of Kuokuiskii Nasleg are provided. The power demand curves were modeled for four characteristic days of the year, and they can be used in the future for designing a power supply system for the settlement. To enhance the accuracy of the method, a series of measures based on specific features of a neural network's functioning are proposed.

  14. Stand-Alone Solar Organic Rankine Cycle Water Pumping System and Its Economic Viability in Nepal

    Directory of Open Access Journals (Sweden)

    Suresh Baral

    2015-12-01

    Full Text Available The current study presents the concept of a stand-alone solar organic Rankine cycle (ORC water pumping system for rural Nepalese areas. Experimental results for this technology are presented based on a prototype. The economic viability of the system was assessed based on solar radiation data of different Nepalese geographic locations. The mechanical power produced by the solar ORC is coupled with a water pumping system for various applications, such as drinking and irrigation. The thermal efficiency of the system was found to be 8% with an operating temperature of 120 °C. The hot water produced by the unit has a temperature of 40 °C. Economic assessment was done for 1-kW and 5-kW solar ORC water pumping systems. These systems use different types of solar collectors: a parabolic trough collector (PTC and an evacuated tube collector (ETC. The economic analysis showed that the costs of water are $2.47/m3 (highest and $1.86/m3 (lowest for the 1-kW system and a 150-m pumping head. In addition, the cost of water is reduced when the size of the system is increased and the pumping head is reduced. The minimum volumes of water pumped are 2190 m3 and 11,100 m3 yearly for 1 kW and 5 kW, respectively. The payback period is eight years with a profitability index of 1.6. The system is highly feasible and promising in the context of Nepal.

  15. Optimum capacity determination of stand-alone hybrid generation system considering cost and reliability

    International Nuclear Information System (INIS)

    Chen, Hung-Cheng

    2013-01-01

    Highlights: ► This paper presents a methodology for the installation capacity optimization. ► Hybrid generation system is optimized by application of adaptive genetic algorithm. ► A cost investigation is made under various conditions and component characteristics. ► The optimization scheme is validated to meet the annual power load demand. -- Abstract: The aim of this work is to present an optimization methodology for the installation capacity of a stand-alone hybrid generation system, taking into consideration the cost and reliability. Firstly, on the basis of derived steady state models of a wind generator (WG), a photovoltaic array (PV), a battery and an inverter, the hybrid generation system is modeled for the purpose of capacity optimization. Secondly, the power system is analyzed for determining both the system structure and the operation control strategy. Thirdly, according to hourly weather database of wind speed, temperature and solar irradiation, annual power generation capacity is estimated for the system match design in order that an annual power load demand can be met. The capacity determination of a hybrid generation system becomes complicated as a result of the uncertainty in the renewable energy together with load demand and the nonlinearity of system components. Aimed at the power system reliability and the cost minimization, the capacity of a hybrid generation system is optimized by application of an adaptive genetic algorithm (AGA) to individual power generation units. A total cost investigation is made under various conditions, such as wind generator power curves, battery discharge depth and the loss of load probability (LOLP). At the end of this work, the capacity of a hybrid generation system is optimized at two installation sites, namely the offshore Orchid Island and Wuchi in Taiwan. The optimization scheme is validated to optimize power capacities of a photovoltaic array, a battery and a wind turbine generator with a relative

  16. The eBioKit, a stand-alone educational platform for bioinformatics.

    Science.gov (United States)

    Hernández-de-Diego, Rafael; de Villiers, Etienne P; Klingström, Tomas; Gourlé, Hadrien; Conesa, Ana; Bongcam-Rudloff, Erik

    2017-09-01

    Bioinformatics skills have become essential for many research areas; however, the availability of qualified researchers is usually lower than the demand and training to increase the number of able bioinformaticians is an important task for the bioinformatics community. When conducting training or hands-on tutorials, the lack of control over the analysis tools and repositories often results in undesirable situations during training, as unavailable online tools or version conflicts may delay, complicate, or even prevent the successful completion of a training event. The eBioKit is a stand-alone educational platform that hosts numerous tools and databases for bioinformatics research and allows training to take place in a controlled environment. A key advantage of the eBioKit over other existing teaching solutions is that all the required software and databases are locally installed on the system, significantly reducing the dependence on the internet. Furthermore, the architecture of the eBioKit has demonstrated itself to be an excellent balance between portability and performance, not only making the eBioKit an exceptional educational tool but also providing small research groups with a platform to incorporate bioinformatics analysis in their research. As a result, the eBioKit has formed an integral part of training and research performed by a wide variety of universities and organizations such as the Pan African Bioinformatics Network (H3ABioNet) as part of the initiative Human Heredity and Health in Africa (H3Africa), the Southern Africa Network for Biosciences (SAnBio) initiative, the Biosciences eastern and central Africa (BecA) hub, and the International Glossina Genome Initiative.

  17. "Candidatus Fokinia solitaria", a Novel "Stand-Alone" Symbiotic Lineage of Midichloriaceae (Rickettsiales.

    Directory of Open Access Journals (Sweden)

    Franziska Szokoli

    Full Text Available Recently, the family Midichloriaceae has been described within the bacterial order Rickettsiales. It includes a variety of bacterial endosymbionts detected in different metazoan host species belonging to Placozoa, Cnidaria, Arthropoda and Vertebrata. Representatives of Midichloriaceae are also considered possible etiological agents of certain animal diseases. Midichloriaceae have been found also in protists like ciliates and amoebae. The present work describes a new bacterial endosymbiont, "Candidatus Fokinia solitaria", retrieved from three different strains of a novel Paramecium species isolated from a wastewater treatment plant in Rio de Janeiro (Brazil. Symbionts were characterized through the full-cycle rRNA approach: SSU rRNA gene sequencing and fluorescence in situ hybridization (FISH with three species-specific oligonucleotide probes. In electron micrographs, the tiny rod-shaped endosymbionts (1.2 x 0.25-0.35 μm in size were not surrounded by a symbiontophorous vacuole and were located in the peripheral host cytoplasm, stratified in the host cortex in between the trichocysts or just below them. Frequently, they occurred inside autolysosomes. Phylogenetic analyses of Midichloriaceae apparently show different evolutionary pathways within the family. Some genera, such as "Ca. Midichloria" and "Ca. Lariskella", have been retrieved frequently and independently in different hosts and environmental surveys. On the contrary, others, such as Lyticum, "Ca. Anadelfobacter", "Ca. Defluviella" and the presently described "Ca. Fokinia solitaria", have been found only occasionally and associated to specific host species. These last are the only representatives in their own branches thus far. Present data do not allow to infer whether these genera, which we named "stand-alone lineages", are an indication of poorly sampled organisms, thus underrepresented in GenBank, or represent fast evolving, highly adapted evolutionary lineages.

  18. Stand-Alone Lateral Interbody Fusion for the Treatment of Low-Grade Degenerative Spondylolisthesis

    Directory of Open Access Journals (Sweden)

    Luis Marchi

    2012-01-01

    Full Text Available The purpose of this paper was to investigate the stand-alone lateral interbody fusion as a minimally invasive option for the treatment of low-grade degenerative spondylolisthesis with a minimum 24-month followup. Prospective nonrandomized observational single-center study. 52 consecutive patients (67.6±10 y/o; 73.1% female; 27.4±3.4 BMI with single-level grade I/II single-level degenerative spondylolisthesis without significant spine instability were included. Fusion procedures were performed as retroperitoneal lateral transpsoas interbody fusions without screw supplementation. The procedures were performed in average 73.2 minutes and with less than 50cc blood loss. VAS and Oswestry scores showed lasting improvements in clinical outcomes (60% and 54.5% change, resp.. The vertebral slippage was reduced in 90.4% of cases from mean values of 15.1% preoperatively to 7.4% at 6-week followup (P<0.001 and was maintained through 24 months (7.1%, P<0.001. Segmental lordosis (P<0.001 and disc height (P<0.001 were improved in postop evaluations. Cage subsidence occurred in 9/52 cases (17% and 7/52 cases (13% spine levels needed revision surgery. At the 24-month evaluation, solid fusion was observed in 86.5% of the levels treated. The minimally invasive lateral approach has been shown to be a safe and reproducible technique to treat low-grade degenerative spondylolisthesis.

  19. A Low-Power Wearable Stand-Alone Tongue Drive System for People With Severe Disabilities.

    Science.gov (United States)

    Jafari, Ali; Buswell, Nathanael; Ghovanloo, Maysam; Mohsenin, Tinoosh

    2018-02-01

    This paper presents a low-power stand-alone tongue drive system (sTDS) used for individuals with severe disabilities to potentially control their environment such as computer, smartphone, and wheelchair using their voluntary tongue movements. A low-power local processor is proposed, which can perform signal processing to convert raw magnetic sensor signals to user-defined commands, on the sTDS wearable headset, rather than sending all raw data out to a PC or smartphone. The proposed sTDS significantly reduces the transmitter power consumption and subsequently increases the battery life. Assuming the sTDS user issues one command every 20 ms, the proposed local processor reduces the data volume that needs to be wirelessly transmitted by a factor of 64, from 9.6 to 0.15 kb/s. The proposed processor consists of three main blocks: serial peripheral interface bus for receiving raw data from magnetic sensors, external magnetic interference attenuation to attenuate external magnetic field from the raw magnetic signal, and a machine learning classifier for command detection. A proof-of-concept prototype sTDS has been implemented with a low-power IGLOO-nano field programmable gate array (FPGA), bluetooth low energy, battery and magnetic sensors on a headset, and tested. At clock frequency of 20 MHz, the processor takes 6.6 s and consumes 27 nJ for detecting a command with a detection accuracy of 96.9%. To further reduce power consumption, an application-specified integrated circuit processor for the sTDS is implemented at the postlayout level in 65-nm CMOS technology with 1-V power supply, and it consumes 0.43 mW, which is 10 lower than FPGA power consumption and occupies an area of only 0.016 mm.

  20. Probabilistic modelling and analysis of stand-alone hybrid power systems

    International Nuclear Information System (INIS)

    Lujano-Rojas, Juan M.; Dufo-López, Rodolfo; Bernal-Agustín, José L.

    2013-01-01

    As a part of the Hybrid Intelligent Algorithm, a model based on an ANN (artificial neural network) has been proposed in this paper to represent hybrid system behaviour considering the uncertainty related to wind speed and solar radiation, battery bank lifetime, and fuel prices. The Hybrid Intelligent Algorithm suggests a combination of probabilistic analysis based on a Monte Carlo simulation approach and artificial neural network training embedded in a genetic algorithm optimisation model. The installation of a typical hybrid system was analysed. Probabilistic analysis was used to generate an input–output dataset of 519 samples that was later used to train the ANNs to reduce the computational effort required. The generalisation ability of the ANNs was measured in terms of RMSE (Root Mean Square Error), MBE (Mean Bias Error), MAE (Mean Absolute Error), and R-squared estimators using another data group of 200 samples. The results obtained from the estimation of the expected energy not supplied, the probability of a determined reliability level, and the estimation of expected value of net present cost show that the presented model is able to represent the main characteristics of a typical hybrid power system under uncertain operating conditions. - Highlights: • This paper presents a probabilistic model for stand-alone hybrid power system. • The model considers the main sources of uncertainty related to renewable resources. • The Hybrid Intelligent Algorithm has been applied to represent hybrid system behaviour. • The installation of a typical hybrid system was analysed. • The results obtained from the study case validate the presented model

  1. X-ray microbeam stand-alone facility for cultured cells irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bożek, Sebastian, E-mail: sebastian.bozek@yahoo.com [Jagiellonian University Medical College, Department of Pharmaceutical Biophysics, Krakow (Poland); Bielecki, Jakub; Wiecheć, Anna; Lekki, Janusz; Stachura, Zbigniew; Pogoda, Katarzyna; Lipiec, Ewelina; Tkocz, Konrad; Kwiatek, Wojciech M. [Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow (Poland)

    2017-03-01

    Highlights: • An X-ray microbeam line for irradiation of living cultured cells was constructed. • A step by step explanation of working principles with engineering details, procedures and calculations is presented. • A model of beam and cell interaction is presented. • A method of uniform irradiation of living cells with an exact dose per a cell is presented. • Results of preliminary experiments are presented. - Abstract: The article describes an X-ray microbeam standalone facility dedicated for irradiation of living cultured cells. The article can serve as an advice for such facilities construction, as it begins from engineering details, through mathematical modeling and experimental procedures, ending up with preliminary experimental results and conclusions. The presented system consists of an open type X-ray tube with microfocusing down to about 2 μm, an X-ray focusing system with optical elements arranged in the nested Kirckpatrick-Baez (or Montel) geometry, a sample stand and an optical microscope with a scientific digital CCD camera. For the beam visualisation an X-ray sensitive CCD camera and a spectral detector are used, as well as a scintillator screen combined with the microscope. A method of precise one by one irradiation of previously chosen cells is presented, as well as a fast method of uniform irradiation of a chosen sample area. Mathematical models of beam and cell with calculations of kerma and dose are presented. The experiments on dose-effect relationship, kinetics of DNA double strand breaks repair, as well as micronuclei observation were performed on PC-3 (Prostate Cancer) cultured cells. The cells were seeded and irradiated on Mylar foil, which covered a hole drilled in the Petri dish. DNA lesions were visualised with γ-H2AX marker combined with Alexa Fluor 488 fluorescent dye.

  2. A standalone Internet cognitive behavior therapy treatment for social anxiety in adults who stutter: CBTpsych.

    Science.gov (United States)

    Helgadóttir, Fjóla Dögg; Menzies, Ross G; Onslow, Mark; Packman, Ann; O'Brian, Sue

    2014-09-01

    Social anxiety is common for those who stutter and efficacious cognitive behavior therapy (CBT) for them appears viable. However, there are difficulties with provision of CBT services for anxiety among those who stutter. Standalone Internet CBT treatment is a potential solution to those problems. CBTpsych is a fully automated, online social anxiety intervention for those who stutter. This report is a Phase I trial of CBTpsych. Fourteen participants were allowed 5 months to complete seven sections of CBTpsych. Pre-treatment and post-treatment assessments tested for social anxiety, common unhelpful thoughts related to stuttering, quality of life and stuttering frequency. Significant post-treatment improvements in social anxiety, unhelpful thoughts, and quality of life were reported. Five of seven participants diagnosed with social anxiety lost those diagnoses at post-treatment. The two participants who did not lose social anxiety diagnoses did not complete all the CBTpsych modules. CBTpsych did not improve stuttering frequency. Eleven of the fourteen participants who began treatment completed Section 4 or more of the CBTpsych intervention. CBTpsych provides a potential means to provide CBT treatment for social anxiety associated with stuttering, to any client without cost, regardless of location. Further clinical trials are warranted. At the end of this activity the reader will be able to: (a) describe that social anxiety is common in those who stutter; (b) discuss the origin of social anxiety and the associated link with bullying; (c) summarize the problems in provision of effective evidence based cognitive behavior therapy for adults who stutter; (d) describe a scalable computerized treatment designed to tackle the service provision gap; (e) describe the unhelpful thoughts associated with stuttering that this fully automated computer program was able to tackle; (f) list the positive outcomes for individuals who stuttered that participated in this trial such as the

  3. Feasibility study and energy conversion analysis of stand-alone hybrid renewable energy system

    International Nuclear Information System (INIS)

    Baghdadi, Fazia; Mohammedi, Kamal; Diaf, Said; Behar, Omar

    2015-01-01

    Highlights: • Hybrid stand-alone wind–solar–fossil power system is analyzed. • Measurement data are used to evaluate system performance. • The proposed system can generate about 70% from renewables. • Such a hybrid plant is very promising for remote regions in Algeria. - Abstract: There is a great interest in the development of renewable power technologies in Algeria, and more particularly hybrid concept. The present paper has investigated the performance of hybrid PV–Wind–Diesel–Battery configuration based on hourly measurements of Adrar climate (southern Algeria). Data of global solar radiation, ambient temperature and wind speed for a period of one year have been used. Firstly, the proposed hybrid system has been optimized by means of HOMER software. The optimization process has been carried out taking into account renewable resources potential and energy demand; while maximizing renewable electricity use and fuel saving are the purpose. In the second step, a mathematical model has been developed to ensure efficient energy management on the basis of various operation strategies. The analysis has shown that renewable energy system (PV–Wind) is able to supply about 70% of the demand. Wind power has ranked first with 43% of the annual total electricity production followed by diesel generator (with 31%) while the remaining fraction is being to PV panels. In this context, 69% of the fossil fuel can be saved when using the proposed hybrid configuration instead of the diesel generators that are currently installed in most remote regions in Algeria. Such a concept is very promising to meet the focus of renewable energy program announced in 2011.

  4. Control strategy of wind turbine based on permanent magnet synchronous generator and energy storage for stand-alone systems

    DEFF Research Database (Denmark)

    Deng, Fujin; Liu, Dong; Chen, Zhe

    2017-01-01

    This paper investigates a variable speed wind turbine based on permanent magnet synchronous generator and a full-scale power converter in a stand-alone system. An energy storage system(ESS) including battery and fuel cell-electrolyzer combination is connected to the DC link of the full-scale power...... converter through the power electronics interface. Wind is the primary power source of the system, the battery and FC-electrolyzer combination is used as a backup and a long-term storage system to provide or absorb power in the stand-alone system, respectively. In this paper, a control strategy is proposed...... for the operation of this variable speed wind turbine in a stand-alone system, where the generator-side converter and the ESS operate together to meet the demand of the loads. This control strategy is competent for supporting the variation of the loads or wind speed and limiting the DC-link voltage of the full...

  5. Effect of wind generation system types on Micro-Grid (MG) fault performance during both standalone and grid connected modes

    International Nuclear Information System (INIS)

    Kamel, Rashad M.

    2014-01-01

    Highlights: • This paper evaluated the effects of different wind system types on fault performance of Micro-Grid. • Both standalone and grid connected modes are considered. • The MG earthing system configuration is taken in consideration. - Abstract: Recently, there are three wind generation (WG) system types. The first type is called Fixed Speed Wind Generation (FSWG) system, which employs squirrel cage induction generators. Double Fed Induction Generator (DFIG) is utilized in the second type. The third type is called Full Converter Wind Generation (FCWG) system, which is interfaced with Micro-Grid (MG) through a back to back converter. During fault occurrence, each WG has its performance and characteristics which are determined by the generator physical characteristics and the MG earthing system configuration. For some WG types, the fault current depends also on the control algorithm of the power converter. The main target of this paper is to investigate and estimate how the fault performance of MG during both standalone and grid-connected modes is influenced by the type of WG. It is found during standalone mode that the type of the employed WG has a dominant impact on the MG performance under fault disturbance. On the contrary, the type of the employed WG has a negligible effect on the MG fault performance during grid-connected mode. This is because the main grid contributes most of the fault current. Effects of earthing system type on MG performance are highlighted

  6. Effects of Medical Device Regulations on the Development of Stand-Alone Medical Software: A Pilot Study.

    Science.gov (United States)

    Blagec, Kathrin; Jungwirth, David; Haluza, Daniela; Samwald, Matthias

    2018-01-01

    Medical device regulations which aim to ensure safety standards do not only apply to hardware devices but also to standalone medical software, e.g. mobile apps. To explore the effects of these regulations on the development and distribution of medical standalone software. We invited a convenience sample of 130 domain experts to participate in an online survey about the impact of current regulations on the development and distribution of medical standalone software. 21 respondents completed the questionnaire. Participants reported slight positive effects on usability, reliability, and data security of their products, whereas the ability to modify already deployed software and customization by end users were negatively impacted. The additional time and costs needed to go through the regulatory process were perceived as the greatest obstacles in developing and distributing medical software. Further research is needed to compare positive effects on software quality with negative impacts on market access and innovation. Strategies for avoiding over-regulation while still ensuring safety standards need to be devised.

  7. Optimum autonomous stand-alone photovoltaic system design on the basis of energy pay-back analysis

    International Nuclear Information System (INIS)

    Kaldellis, J.K.; Zafirakis, D.; Kondili, E.

    2009-01-01

    Stand-alone photovoltaic (PV) systems comprise one of the most promising electrification solutions for covering the demand of remote consumers. However, such systems are strongly questioned due to extreme life-cycle (LC) energy requirements. For similar installations to be considered as environmentally sustainable, their LC energy content must be compensated by the respective useful energy production, i.e. their energy pay-back period (EPBP) should be found less than their service period. In this context, an optimum sizing methodology is currently developed, based on the criterion of minimum embodied energy. Various energy autonomous stand-alone PV-lead-acid battery systems are examined and two different cases are investigated; a high solar potential area and a medium solar potential area. By considering that the PV-battery (PV-Bat) system's useful energy production is equal to the remote consumer's electricity consumption, optimum cadmium telluride (CdTe) based systems yield the minimum EPBP (15 years). If achieving to exploit the net PV energy production however, the EPBP is found less than 20 years for all PV types. Finally, the most interesting finding concerns the fact that in all cases examined the contribution of the battery component exceeds 27% of the system LC energy requirements, reflecting the difference between grid-connected and stand-alone configurations.

  8. A Case Study of Control and Improved Simplified Swarm Optimization for Economic Dispatch of a Stand-Alone Modular Microgrid

    Directory of Open Access Journals (Sweden)

    Xianyong Zhang

    2018-03-01

    Full Text Available Due to the complex configuration and control framework, the conventional microgrid is not cost-effective for engineering applications with small or medium capacity. A stand-alone modular microgrid with separated AC bus and decentralized control strategy is proposed in this paper. Each module is a self-powered system, which consists of wind and solar power, a storage battery, load and three-port converter. The modules are interconnected by three-port converters to form the microgrid. Characteristics, operation principle, control of the modular microgrid and the three-port converter are analyzed in detail. Distributed storage batteries enable power exchanges among modules to enhance economic returns. Economic dispatch of the stand-alone modular microgrid is a mixed-integer programming problem. A day-ahead operation optimization model including fuel cost, battery operation cost, and power transmission cost is established. Because there are so many constraints, it is difficult to produce a feasible solution and even more difficult to have an improved solution. An improved simplified swarm optimization (iSSO method is therefore proposed. The iSSO scheme designs the new update mechanism and survival of the fittest policy. The experimental results from the demonstration project on DongAo Island reflect the effectiveness of the stand-alone modular microgrid and the economic dispatch strategy based on the iSSO method.

  9. Methanol production via pressurized entrained flow biomass gasification – Techno-economic comparison of integrated vs. stand-alone production

    International Nuclear Information System (INIS)

    Andersson, Jim; Lundgren, Joakim; Marklund, Magnus

    2014-01-01

    The main objective with this work was to investigate techno-economically the opportunity for integrated gasification-based biomass-to-methanol production in an existing chemical pulp and paper mill. Three different system configurations using the pressurized entrained flow biomass gasification (PEBG) technology were studied, one stand-alone plant, one where the bark boiler in the mill was replaced by a PEBG unit and one with a co-integration of a black liquor gasifier operated in parallel with a PEBG unit. The cases were analysed in terms of overall energy efficiency (calculated as electricity-equivalents) and process economics. The economics was assessed under the current as well as possible future energy market conditions. An economic policy support was found to be necessary to make the methanol production competitive under all market scenarios. In a future energy market, integrating a PEBG unit to replace the bark boiler was the most beneficial case from an economic point of view. In this case the methanol production cost was reduced in the range of 11–18 Euro per MWh compared to the stand-alone case. The overall plant efficiency increased approximately 7%-units compared to the original operation of the mill and the non-integrated stand-alone case. In the case with co-integration of the two parallel gasifiers, an equal increase of the system efficiency was achieved, but the economic benefit was not as apparent. Under similar conditions as the current market and when methanol was sold to replace fossil gasoline, co-integration of the two parallel gasifiers was the best alternative based on received IRR. - Highlights: • Techno-economic results regarding integration of methanol synthesis processes in a pulp and paper mill are presented. • The overall energy efficiency increases in integrated methanol production systems compared to stand-alone production units. • The economics of the integrated system improves compared to stand-alone alternatives. • Tax

  10. Maintenance of Segmental Lordosis and Disk Height in Stand-alone and Instrumented Extreme Lateral Interbody Fusion (XLIF).

    Science.gov (United States)

    Malham, Gregory M; Ellis, Ngaire J; Parker, Rhiannon M; Blecher, Carl M; White, Rohan; Goss, Ben; Seex, Kevin A

    2017-03-01

    A prospective single-surgeon nonrandomized clinical study. To evaluate the radiographic and clinical outcomes, by fixation type, in extreme lateral interbody fusion (XLIF) patients and provide an algorithm for determining patients suitable for stand-alone XLIF. XLIF may be supplemented with pedicle screw fixation, however, since stabilizing structures remain intact, it is suggested that stand-alone XLIF can be used for certain indications. This eliminates the associated morbidity, though subsidence rates may be elevated, potentially minimizing the clinical benefits. A fixation algorithm was developed after evaluation of patient outcomes from the surgeon's first 30 cases. This algorithm was used prospectively for 40 subsequent patients to determine the requirement for supplemental fixation. Preoperative, postoperative, and 12-month follow-up computed tomography scans were measured for segmental and global lumbar lordosis and posterior disk height. Clinical outcome measures included back and leg pain (visual analogue scale), Oswestry Disability Index (ODI), and SF-36 physical and mental component scores (PCS and MCS). Preoperatively to 12-month follow-up there were increases in segmental lordosis (7.9-9.4 degrees, P=0.0497), lumbar lordosis (48.8-55.2 degrees, P=0.0328), and disk height (3.7-5.5 mm, P=0.0018); there were also improvements in back (58.6%) and leg pain (60.0%), ODI (44.4%), PCS (56.7%), and MCS (16.1%) for stand-alone XLIF. For instrumented XLIF, segmental lordosis (7.6-10.5 degrees, P=0.0120) and disk height (3.5-5.6 mm, Plordosis decreased (51.1-45.8 degrees, P=0.2560). Back (49.8%) and leg pain (30.8%), ODI (32.3%), PCS (37.4%), and MCS (2.0%) were all improved. Subsidence occurred in 3 (7.5%) stand-alone patients. The XLIF treatment fixation algorithm provided a clinical pathway to select suitable patients for stand-alone XLIF. These patients achieved positive clinical outcomes, satisfactory fusion rates, with sustained correction of lordosis and

  11. Stand-Alone Personalized Normative Feedback for College Student Drinkers: A Meta-Analytic Review, 2004 to 2014.

    Directory of Open Access Journals (Sweden)

    Keri B Dotson

    Full Text Available Norms clarification has been identified as an effective component of college student drinking interventions, prompting research on norms clarification as a single-component intervention known as Personalized Normative Feedback (PNF. Previous reviews have examined PNF in combination with other components but not as a stand-alone intervention.To investigate the degree to which computer-delivered stand-alone personalized normative feedback interventions reduce alcohol consumption and alcohol-related harms among college students and to compare gender-neutral and gender-specific PNF.Electronic databases were searched systematically through November 2014. Reference lists were reviewed manually and forward and backward searches were conducted.Outcome studies that compared computer-delivered, stand-alone PNF intervention with an assessment only, attention-matched, or active treatment control and reported alcohol use and harms among college students.Between-group effect sizes were calculated as the standardized mean difference in change scores between treatment and control groups divided by pooled standard deviation. Within-group effect sizes were calculated as the raw mean difference between baseline and follow-up divided by pooled within-groups standard deviation.Eight studies (13 interventions with a total of 2,050 participants were included. Compared to control participants, students who received gender-neutral (dbetween = 0.291, 95% CI [0.159, 0.423] and gender-specific PNF (dbetween = 0.284, 95% CI [0.117, 0.451] reported greater reductions in drinking from baseline to follow-up. Students who received gender-neutral PNF reported 3.027 (95% CI [2.171, 3.882] fewer drinks per week at first follow-up and gender-specific PNF reported 3.089 (95% CI [0.992, 5.186] fewer drinks. Intervention effects were small for harms (dbetween = 0.157, 95% CI [0.037, 0.278].Computer-delivered PNF is an effective stand-alone approach for reducing college student

  12. Stand-Alone Personalized Normative Feedback for College Student Drinkers: A Meta-Analytic Review, 2004 to 2014.

    Science.gov (United States)

    Dotson, Keri B; Dunn, Michael E; Bowers, Clint A

    2015-01-01

    Norms clarification has been identified as an effective component of college student drinking interventions, prompting research on norms clarification as a single-component intervention known as Personalized Normative Feedback (PNF). Previous reviews have examined PNF in combination with other components but not as a stand-alone intervention. To investigate the degree to which computer-delivered stand-alone personalized normative feedback interventions reduce alcohol consumption and alcohol-related harms among college students and to compare gender-neutral and gender-specific PNF. Electronic databases were searched systematically through November 2014. Reference lists were reviewed manually and forward and backward searches were conducted. Outcome studies that compared computer-delivered, stand-alone PNF intervention with an assessment only, attention-matched, or active treatment control and reported alcohol use and harms among college students. Between-group effect sizes were calculated as the standardized mean difference in change scores between treatment and control groups divided by pooled standard deviation. Within-group effect sizes were calculated as the raw mean difference between baseline and follow-up divided by pooled within-groups standard deviation. Eight studies (13 interventions) with a total of 2,050 participants were included. Compared to control participants, students who received gender-neutral (dbetween = 0.291, 95% CI [0.159, 0.423]) and gender-specific PNF (dbetween = 0.284, 95% CI [0.117, 0.451]) reported greater reductions in drinking from baseline to follow-up. Students who received gender-neutral PNF reported 3.027 (95% CI [2.171, 3.882]) fewer drinks per week at first follow-up and gender-specific PNF reported 3.089 (95% CI [0.992, 5.186]) fewer drinks. Intervention effects were small for harms (dbetween = 0.157, 95% CI [0.037, 0.278]). Computer-delivered PNF is an effective stand-alone approach for reducing college student drinking and

  13. Study on Soft Phase Locked Method to Solving the Synchronization Problem of Active Power Filter in Stand-alone Power Grid

    DEFF Research Database (Denmark)

    Zhuo, Fang; Wu, Longhui; Chen, Zhe

    2009-01-01

    on zero-cross detection can't work effectively in small rating stand-alone power grid. Then a soft phase locked loop with additional filter is proposed. It can lock the phase angle on to the positive sequence of fundamental voltage accurately and rapidly. It ensures the performance of APF applied...... in the small rating stand-alone power grid. Moreover, the soft phase locked loop is easy to be implemented in a Digital Signal Processor (DSP). Simulation and experimental results validate that the soft phase locked loop has satisfactory performance.......Traditional LC filters can't work stably in small rating stand-alone power grid. So active power filter (APF) is becoming an important tool to solve the power quality problem in small rating stand-alone power grid. In most current detection algorithm of APF, it needs a synchronizing signal. Firstly...

  14. Modeling and control of distributed energy systems during transition between grid connected and standalone modes

    Science.gov (United States)

    Arafat, Md Nayeem

    Distributed generation systems (DGs) have been penetrating into our energy networks with the advancement in the renewable energy sources and energy storage elements. These systems can operate in synchronism with the utility grid referred to as the grid connected (GC) mode of operation, or work independently, referred to as the standalone (SA) mode of operation. There is a need to ensure continuous power flow during transition between GC and SA modes, referred to as the transition mode, in operating DGs. In this dissertation, efficient and effective transition control algorithms are developed for DGs operating either independently or collectively with other units. Three techniques are proposed in this dissertation to manage the proper transition operations. In the first technique, a new control algorithm is proposed for an independent DG which can operate in SA and GC modes. The proposed transition control algorithm ensures low total harmonic distortion (THD) and less voltage fluctuation during mode transitions compared to the other techniques. In the second technique, a transition control is suggested for a collective of DGs operating in a microgrid system architecture to improve the reliability of the system, reduce the cost, and provide better performance. In this technique, one of the DGs in a microgrid system, referred to as a dispatch unit , takes the additional responsibility of mode transitioning to ensure smooth transition and supply/demand balance in the microgrid. In the third technique, an alternative transition technique is proposed through hybridizing the current and droop controllers. The proposed hybrid transition control technique has higher reliability compared to the dispatch unit concept. During the GC mode, the proposed hybrid controller uses current control. During the SA mode, the hybrid controller uses droop control. During the transition mode, both of the controllers participate in formulating the inverter output voltage but with different

  15. The Equipment of Using AZOLLA for O2-Supplimentation and its Test

    Science.gov (United States)

    Liu, Xia-Shi; Chen, Min; Bian, Zu-Liang; Liu, Chung-Chu

    The water-consuming amount in a long-term astro-navigation is large. In order to reduce the burden of water supply from Earth ground, the space station needs to resolve the problems of water supply. For this reason, the recovery and regeneration of urine solution of spacemen, and its utilization possess a key importance. Many investigations on this aspect have been reported. Our research based on "biological absorption-purification-UV photocatalytic oxidation" techniques with a relevant treating equipment that for a comprehensive treatment to fresh urine of spacemen has been created. In this equipment, the urine solution was used as the nutrient solution for the biological parts in ecological life ensurant system, after absorbing the nutrient, it was decomposed, metabolized and purified in some distance, and created a favorable condition for the follow-up oxidation treatment by UV-Photocatalytic Oxidation. After these two processes, the treated urine solution reached the GB5749-85 standard of water quality. Some main indexes are as table one. Chroma<5-15 Feculent degree-NTU-1.20-3 --5 Total rigidity-according to CaCO3-mg/L-3.60-450 N-NO3--mg/L-0.60-20 Soluble total solid-mg/L-543-1000 Bacterial gross-cfu/ml-13-100 Coliform group-No./L-<3-3 Key words-Photocatalytic Oxidation , Ultraviolet

  16. An optimized Fuzzy Logic Controller by Water Cycle Algorithm for power management of Stand-alone Hybrid Green Power generation

    International Nuclear Information System (INIS)

    Sarvi, Mohammad; Avanaki, Isa Nasiri

    2015-01-01

    Highlights: • A new method to improve the performance of renewable power management is proposed. • The proposed method is based on Fuzzy Logic optimized by the Water Cycle Algorithm. • The proposed method characteristics are compared with two other methods. • The comparisons confirm that the proposed method is robust and effectiveness one. - Abstract: This paper aims to improve the power management system of a Stand-alone Hybrid Green Power generation based on the Fuzzy Logic Controller optimized by the Water Cycle Algorithm. The proposed Stand-alone Hybrid Green Power consists of wind energy conversion and photovoltaic systems as primary power sources and a battery, fuel cell, and Electrolyzer as energy storage systems. Hydrogen is produced from surplus power generated by the wind energy conversion and photovoltaic systems of Stand-alone Hybrid Green Power and stored in the hydrogen storage tank for fuel cell later using when the power generated by primary sources is lower than load demand. The proposed optimized Fuzzy Logic Controller based power management system determines the power that is generated by fuel cell or use by Electrolyzer. In a hybrid system, operation and maintenance cost and reliability of the system are the important issues that should be considered in studies. In this regard, Water Cycle Algorithm is used to optimize membership functions in order to simultaneously minimize the Loss of Power Supply Probability and operation and maintenance. The results are compared with the particle swarm optimization and the un-optimized Fuzzy Logic Controller power management system to prove that the proposed method is robust and effective. Reduction in Loss of Power Supply Probability and operation and maintenance, are the most advantages of the proposed method. Moreover the level of the State of Charge of the battery in the proposed method is higher than other mentioned methods which leads to increase battery lifetime.

  17. Hierarchical energy management system for stand-alone hybrid system based on generation costs and cascade control

    International Nuclear Information System (INIS)

    Torreglosa, J.P.; García, P.; Fernández, L.M.; Jurado, F.

    2014-01-01

    Highlights: • We present an energy management system for a stand-alone WT/PV/hydrogen/battery hybrid system. • Hierarchical control composed by master and slave control strategies. • Control assures reliable electricity support for stand-alone applications subject to technical and economic criteria. - Abstract: This paper presents an energy management system (EMS) for stand-alone hybrid systems composed by photovoltaic (PV) solar panels and a wind turbine (WT) as primary energy sources and two energy storage systems, which are a hydrogen system and a battery. The hydrogen system is composed of fuel cell (FC), electrolyzer and hydrogen storage tank. The EMS is a hierarchical control composed by a master control strategy and a slave control strategy. On the one hand, the master control generates the reference powers to meet several premises (such as to satisfy the load power demand, and to maintain the hydrogen tank level and the state of charge (SOC) of the battery between their target margins), taking also into account economic aspects to discriminate between using the battery or hydrogen system. On the other hand, the slave control modifies the reference powers generated by the master control according to the energy sources dynamic limitations, and maintains the DC bus voltage at its reference value. The models, implemented in MATLAB-Simulink environment, have been developed from commercially available components. To check the viability of the proposed EMS, two kinds of simulations were carried out: (1) A long-term simulation of 25 years (expected lifetime of the system) with a sample time of one hour to validate the master control of the EMS; and (2) A short-term simulation with sudden net power variations to validate the slave control of the EMS

  18. High-Efficiency Isolated Photovoltaic Microinverter Using Wide-Band Gap Switches for Standalone and Grid-Tied Applications

    Directory of Open Access Journals (Sweden)

    Yu-Chen Liu

    2018-03-01

    Full Text Available An isolated photovoltaic micro-inverter for standalone and grid-tied applications is designed and implemented to achieve high efficiency. System configuration and design considerations, including the proposed active-clamp forward-flyback resonant converter for the DC-DC stage and a dual-frequency full-bridge inverter for the DC-AC stage, are analyzed and discussed. A prototype microinverter system is built and tested. Experimental results verify the feasibility of the proposed system, which achieves 95% power conversion efficiency at full load.

  19. Efficiency of the hybrid solar-wind systems for electricity supply to the stand-alone sites

    International Nuclear Information System (INIS)

    Abdullaev, D.A.; Isaev, R.I.

    2000-01-01

    The features of stand-alone sites and principles of their electricity supply is described there is going observation of the works about conditions of production and efficiency of using autonomy wind turbines and photovoltaics. Their unsufficiency is estimated. The advantages of hybrid systems and their realization schemes is described. The advantage of hybrid solar-wind Battery system (HSWBS) on the basis of own researches and the facts of other authors are given. The conception overall discounting cost is developed on HSWBS case. (Author)

  20. Evaluation of a proper controller performance for maximum-power point tracking of a stand-alone PV system

    Energy Technology Data Exchange (ETDEWEB)

    Nafeh, A.E.-S.A.; Fahmy, F.H. [Electronics Research Institute, Cairo (Egypt); El-Zahab, E.M.A. [Cairo University, Giza (Egypt). Faculty of Engineering

    2003-02-01

    In this paper the implementation of a suggested stand-alone PV system, for maximum-power point tracking (MPPT), is carried out. Also, this paper presents a comparative study, through experimental work, between the conventional PI controller and the fuzzy logic controller (FLC) under different atmospheric conditions. The implemented system with both the PI controller and the FLC gives a good maximum-power operation of the PV array, but the tracking capability for different optimum operating points is better and faster for the case of using the FLC compared to the case of using the PI controller. (author)

  1. A critical evaluation of deterministic methods in size optimisation of reliable and cost effective standalone hybrid renewable energy systems

    International Nuclear Information System (INIS)

    Maheri, Alireza

    2014-01-01

    Reliability of a hybrid renewable energy system (HRES) strongly depends on various uncertainties affecting the amount of power produced by the system. In the design of systems subject to uncertainties, both deterministic and nondeterministic design approaches can be adopted. In a deterministic design approach, the designer considers the presence of uncertainties and incorporates them indirectly into the design by applying safety factors. It is assumed that, by employing suitable safety factors and considering worst-case-scenarios, reliable systems can be designed. In fact, the multi-objective optimisation problem with two objectives of reliability and cost is reduced to a single-objective optimisation problem with the objective of cost only. In this paper the competence of deterministic design methods in size optimisation of reliable standalone wind–PV–battery, wind–PV–diesel and wind–PV–battery–diesel configurations is examined. For each configuration, first, using different values of safety factors, the optimal size of the system components which minimises the system cost is found deterministically. Then, for each case, using a Monte Carlo simulation, the effect of safety factors on the reliability and the cost are investigated. In performing reliability analysis, several reliability measures, namely, unmet load, blackout durations (total, maximum and average) and mean time between failures are considered. It is shown that the traditional methods of considering the effect of uncertainties in deterministic designs such as design for an autonomy period and employing safety factors have either little or unpredictable impact on the actual reliability of the designed wind–PV–battery configuration. In the case of wind–PV–diesel and wind–PV–battery–diesel configurations it is shown that, while using a high-enough margin of safety in sizing diesel generator leads to reliable systems, the optimum value for this margin of safety leading to a

  2. A review of three stand-alone topical thrombins for surgical hemostasis.

    Science.gov (United States)

    Cheng, Christine M; Meyer-Massetti, Carla; Kayser, Steven R

    2009-01-01

    Topical thrombins are active hemostatic agents that can be used to minimize blood loss during surgery. Before 2007, the only topical thrombins available were derived from bovine plasma. Antibody formation to bovine thrombin and/or factor V, with subsequent risk of cross-reactivity with human factor V, and hemorrhagic complications associated with human factor-V deficiencies have been described in case reports of surgeries in which bovine thrombins were used. This risk is now included in the boxed warning section of the bovine thrombin prescribing information. In 2007 and 2008, 2 new topical thrombins from nonbovine sources received approval for use from the US Food and Drug Administration. The 3 active topical thrombins that are currently marketed are bovine plasma-derived thrombin, human plasma-derived thrombin, and human recombinant thrombin. The purpose of this review was to evaluate the literature on the efficacy and safety of topical thrombins and discuss the pharmacoeconomic considerations associated with their use. PubMed, EMBASE, and International Pharmaceutical Abstracts were searched for relevant papers published in English through October 10,2008, using the terms thrombin, human recombinant thrombin, bovine thrombin, plasma derived thrombin, and topical thrombin. Manufacturer-provided materials were also reviewed. Abstracts and unpublished data, as well as evaluations of sealants, adhesives, glues, and other hemostats that contain thrombin mixed with fibrinogen and other clotting factors, were excluded. Four randomized, double-blind studies involving the active, stand-alone topical thrombins were found. The bovine thrombin involved in these studies was the predecessor to the currently marketed, highly purified bovine formulation. No studies comparing the human products, studies involving the highly purified bovine preparation, or placebo-controlled studies involving bovine thrombin were found. In a Phase III comparison of human recombinant thrombin and

  3. Technical Study of a Standalone Photovoltaic-Wind Energy Based Hybrid Power Supply Systems for Island Electrification in Malaysia.

    Directory of Open Access Journals (Sweden)

    Nahidul Hoque Samrat

    Full Text Available Energy is one of the most important factors in the socioeconomic development of a country. In a developing country like Malaysia, the development of islands is mostly related to the availability of electric power. Power generated by renewable energy sources has recently become one of the most promising solutions for the electrification of islands and remote rural areas. But high dependency on weather conditions and the unpredictable nature of these renewable energy sources are the main drawbacks. To overcome this weakness, different green energy sources and power electronic converters need to be integrated with each other. This study presents a battery storage hybrid standalone photovoltaic-wind energy power supply system. In the proposed standalone hybrid system, a DC-DC buck-boost bidirectional converter controller is used to accumulates the surplus hybrid power in the battery bank and supplies this power to the load during the hybrid power shortage by maintaining the constant dc-link voltage. A three-phase voltage source inverter complex vector control scheme is used to control the load side voltage in terms of the voltage amplitude and frequency. Based on the simulation results obtained from MATLAB/Simulink, it has been found that the overall hybrid framework is capable of working under variable weather and load conditions.

  4. GOssTo: a stand-alone application and a web tool for calculating semantic similarities on the Gene Ontology.

    Science.gov (United States)

    Caniza, Horacio; Romero, Alfonso E; Heron, Samuel; Yang, Haixuan; Devoto, Alessandra; Frasca, Marco; Mesiti, Marco; Valentini, Giorgio; Paccanaro, Alberto

    2014-08-01

    We present GOssTo, the Gene Ontology semantic similarity Tool, a user-friendly software system for calculating semantic similarities between gene products according to the Gene Ontology. GOssTo is bundled with six semantic similarity measures, including both term- and graph-based measures, and has extension capabilities to allow the user to add new similarities. Importantly, for any measure, GOssTo can also calculate the Random Walk Contribution that has been shown to greatly improve the accuracy of similarity measures. GOssTo is very fast, easy to use, and it allows the calculation of similarities on a genomic scale in a few minutes on a regular desktop machine. alberto@cs.rhul.ac.uk GOssTo is available both as a stand-alone application running on GNU/Linux, Windows and MacOS from www.paccanarolab.org/gossto and as a web application from www.paccanarolab.org/gosstoweb. The stand-alone application features a simple and concise command line interface for easy integration into high-throughput data processing pipelines. © The Author 2014. Published by Oxford University Press.

  5. SedInConnect: a stand-alone, free and open source tool for the assessment of sediment connectivity

    Science.gov (United States)

    Crema, Stefano; Cavalli, Marco

    2018-02-01

    There is a growing call, within the scientific community, for solid theoretic frameworks and usable indices/models to assess sediment connectivity. Connectivity plays a significant role in characterizing structural properties of the landscape and, when considered in combination with forcing processes (e.g., rainfall-runoff modelling), can represent a valuable analysis for an improved landscape management. In this work, the authors present the development and application of SedInConnect: a free, open source and stand-alone application for the computation of the Index of Connectivity (IC), as expressed in Cavalli et al. (2013) with the addition of specific innovative features. The tool is intended to have a wide variety of users, both from the scientific community and from the authorities involved in the environmental planning. Thanks to its open source nature, the tool can be adapted and/or integrated according to the users' requirements. Furthermore, presenting an easy-to-use interface and being a stand-alone application, the tool can help management experts in the quantitative assessment of sediment connectivity in the context of hazard and risk assessment. An application to a sample dataset and an overview on up-to-date applications of the approach and of the tool shows the development potential of such analyses. The modelled connectivity, in fact, appears suitable not only to characterize sediment dynamics at the catchment scale but also to integrate prediction models and as a tool for helping geomorphological interpretation.

  6. Improved double integral sliding mode MPPT controller based parameter estimation for a stand-alone photovoltaic system

    International Nuclear Information System (INIS)

    Chatrenour, Nasrin; Razmi, Hadi; Doagou-Mojarrad, Hasan

    2017-01-01

    Highlights: • IDISMC based MPPT algorithm is introduced. • Hurwitz stability theorem is used for switching surface coefficients computation. • GA approach is presented for parameter estimation of the stand-alone PV system. - Abstract: In this paper, an Improved Double Integral Sliding Mode MPPT Controller (IDISMC) for a stand-alone photovoltaic (PV) system is proposed. Performance of a sliding mode controller (SMC) is greatly influenced by the choice of the sliding surface. Switching surface coefficients were selected by the use of Hurwitz stability theorem. The IDISMC not only is robust against parametric and non-parametric uncertainties, but also has a very small steady-state error, thanks to the use of double integral of tracking voltage error in the definition of its sliding surface. For realistic simulation, Genetic Algorithm (GA) method was used to estimate parameters of solar panels model. The validity of the proposed double integral SMC in maximum power point tracking was approved by comparing the simulation results obtained for a sample PV system with the results of other methods.

  7. Feasibility Study of Standalone PV-Wind-Diesel Energy Systems for Coastal Residential Application in Pekan, Pahang

    Directory of Open Access Journals (Sweden)

    Zailan Roziah

    2017-01-01

    Full Text Available Techno economic study is feasible to optimize the usage of renewable energy components that targeting low cost of electricity generation system. The selected case study area is coastal area in Pekan, Pahang, Malaysia. The autonomous system designed in this study is hybrid standalone PV-wind-diesel energy system to fulfil a basic power demand of 20.1 kWh/day. Such power system was designed and optimized further to meet the power demand at a minimum cost of energy using energy optimization software, Hybrid Optimization Model for Electric Renewables (HOMER. The analysis focused on the operational characteristics and economics. The standalone PV-wind-diesel energy system has total net present cost about $61, 911 with cost of energy $0.66/kWh. Apparently, the generation of electricity from both wind turbine and PV can be inflated with the diesel generator. In comparison, return of investment (ROI value turned out lower for Feed in Tariff (FIT as compared to self-sustained house. Payback period also longer for FIT program that makes the selling back of electricity generated to Tenaga National Berhad (TNB is considered not favourable.

  8. Technical Study of a Standalone Photovoltaic-Wind Energy Based Hybrid Power Supply Systems for Island Electrification in Malaysia.

    Science.gov (United States)

    Samrat, Nahidul Hoque; Ahmad, Norhafizan; Choudhury, Imtiaz Ahmed; Taha, Zahari

    2015-01-01

    Energy is one of the most important factors in the socioeconomic development of a country. In a developing country like Malaysia, the development of islands is mostly related to the availability of electric power. Power generated by renewable energy sources has recently become one of the most promising solutions for the electrification of islands and remote rural areas. But high dependency on weather conditions and the unpredictable nature of these renewable energy sources are the main drawbacks. To overcome this weakness, different green energy sources and power electronic converters need to be integrated with each other. This study presents a battery storage hybrid standalone photovoltaic-wind energy power supply system. In the proposed standalone hybrid system, a DC-DC buck-boost bidirectional converter controller is used to accumulates the surplus hybrid power in the battery bank and supplies this power to the load during the hybrid power shortage by maintaining the constant dc-link voltage. A three-phase voltage source inverter complex vector control scheme is used to control the load side voltage in terms of the voltage amplitude and frequency. Based on the simulation results obtained from MATLAB/Simulink, it has been found that the overall hybrid framework is capable of working under variable weather and load conditions.

  9. Technical Study of a Standalone Photovoltaic–Wind Energy Based Hybrid Power Supply Systems for Island Electrification in Malaysia

    Science.gov (United States)

    Samrat, Nahidul Hoque; Ahmad, Norhafizan; Choudhury, Imtiaz Ahmed; Taha, Zahari

    2015-01-01

    Energy is one of the most important factors in the socioeconomic development of a country. In a developing country like Malaysia, the development of islands is mostly related to the availability of electric power. Power generated by renewable energy sources has recently become one of the most promising solutions for the electrification of islands and remote rural areas. But high dependency on weather conditions and the unpredictable nature of these renewable energy sources are the main drawbacks. To overcome this weakness, different green energy sources and power electronic converters need to be integrated with each other. This study presents a battery storage hybrid standalone photovoltaic-wind energy power supply system. In the proposed standalone hybrid system, a DC-DC buck-boost bidirectional converter controller is used to accumulates the surplus hybrid power in the battery bank and supplies this power to the load during the hybrid power shortage by maintaining the constant dc-link voltage. A three-phase voltage source inverter complex vector control scheme is used to control the load side voltage in terms of the voltage amplitude and frequency. Based on the simulation results obtained from MATLAB/Simulink, it has been found that the overall hybrid framework is capable of working under variable weather and load conditions. PMID:26121032

  10. Economic and Environmental Assessment of a Renewable Stand-Alone Energy Supply System Using Multi-objective Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dohyun; Han, Seulki; Kim, Jiyong Kim [Incheon National University, Incheon (Korea, Republic of)

    2017-06-15

    This study aims to propose a new optimization-based approach for design and analysis of the stand-alone hybrid energy supply system using renewable energy sources (RES). In the energy supply system, we include multiple energy production technologies such as Photovoltaics (PV), Wind turbine, and fossil-fuel-based AC generator along with different types of energy storage and conversion technologies such as battery and inverter. We then select six different regions of Korea to represent various characteristics of different RES potentials and demand profiles. We finally designed and analyzed the optimal RES stand-alone energy supply system in the selected regions using multiobjective optimization (MOOP) technique, which includes two objective functions: the minimum cost and the minimum CO{sub 2} emission. In addition, we discussed the feasibility and expecting benefits of the systems by comparing to conventional systems of Korea. As a result, the region of the highest RES potential showed the possibility to remarkably reduce CO{sub 2} emissions compared to the conventional system. Besides, the levelized cost of electricity (LCOE) of the RES-based energy system is identified to be slightly higher than conventional energy system: 0.35 and 0.46 $/kWh, respectively. However, the total life-cycle emission of CO{sub 2} (LCECO{sub 2}) can be reduced up to 470 gCO{sub 2}/kWh from 490 gCO{sub 2}/kWh of the conventional systems.

  11. Comparison of pulp-mill-integrated hydrogen production from gasified black liquor with stand-alone production from gasified biomass

    International Nuclear Information System (INIS)

    Andersson, E.; Harvey, S.

    2007-01-01

    When gasified black liquor is used for hydrogen production, significant amounts of biomass must be imported. This paper compares two alternative options for producing hydrogen from biomass: (A) pulp-mill-integrated hydrogen production from gasified back liquor; and (B) stand-alone production of hydrogen from gasified biomass. The comparison assumes that the same amount of biomass that is imported in Alternative A is supplied to a stand-alone hydrogen production plant and that the gasified black liquor in Alternative B is used in a black liquor gasification combined cycle (BLGCC) CHP unit. The comparison is based upon equal amounts of black liquor fed to the gasifier, and identical steam and power requirements for the pulp mill. The two systems are compared on the basis of total CO 2 emission consequences, based upon different assumptions for the reference energy system that reflect different societal CO 2 emissions reduction target levels. Ambitions targets are expected to lead to a more CO 2 -lean reference energy system, in which case hydrogen production from gasified black liquor (Alternative A) is best from a CO 2 emissions' perspective, whereas with high CO 2 emissions associated with electricity production, hydrogen from gasified biomass and electricity from gasified black liquor (Alternative B) is preferable. (author)

  12. Evaluation of a Distributed Photovoltaic System in Grid-Connected and Standalone Applications by Different MPPT Algorithms

    Directory of Open Access Journals (Sweden)

    Ru-Min Chao

    2018-06-01

    Full Text Available Due to the shortage of fossil fuel and the environmental pollution problem, solar energy applications have drawn a lot of attention worldwide. This paper reports the use of the latest patented distributed photovoltaic (PV power system design, including the two possible maximum power point tracking (MPPT algorithms, a power optimizer, and a PV power controller, in grid-connected and standalone applications. A distributed PV system with four amorphous silicon thin-film solar panels is used to evaluate both the quadratic maximization (QM and the Steepest descent (SD MPPT algorithms. The system’s design is different for the QM or the SD MPPT algorithm being used. The test result for the grid-connected silicon-based PV panels will also be reported. Considering the settling time for the power optimizer to be 20 ms, the test result shows that the tracking time for the QM method is close to 200 ms, which is faster when compared with the SD method whose tracking time is 500 ms. Besides this, the use of the QM method provides a more stable power output since the tracking is restricted by a local power optimizer rather than the global tracking the SD method uses. For a standalone PV application, a solar-powered boat design with 18 PV panels using a cascaded MPPT controller is introduced, and it provides flexibility in system design and the effective use of photovoltaic energy.

  13. Multi-objective optimal planning of the stand-alone microgrid system based on different benefit subjects

    International Nuclear Information System (INIS)

    Guo, Li; Wang, Nan; Lu, Hai; Li, Xialin; Wang, Chengshan

    2016-01-01

    As an important means to realize the energetic complementarity and improve the efficiency of renewable resources, the stand-alone microgrid (SAMG) system gains attention increasingly, especially in islands and remote areas. In this paper, considering the interest conflict of the distribution company and the distributed generation owner, a new multi-objective optimal planning model is formulated for medium voltage SAMG. Besides, to avoid the power constraint of distributed generation (DG) once the over-limit voltage occurs, a novel two-step power dispatch control method including the voltage regulation strategy is proposed, in which the absorption of distributed power by energy storage system (ESS) and the reactive power adjustment though its power control system are used to regulate voltage. The goal of this paper is to search the Pareto-optimal front of the site and capacity of DG as well as the contract price between both parties, and thus can provide effective references for practical planning of SAMG. Considering the high cost of ESS, the investment analysis of ESS is also discussed in the paper. - Highlights: • A multi-objective planning model based on different benefit subjects is proposed. • A two-step power dispatch method including the voltage regulation is proposed. • The economical efficiency of the proposed model is analyzed. • The effective reference for the stand-alone microgrid planning is provided.

  14. A Control Approach and Supplementary Controllers for a Stand-Alone System with Predominance of Wind Generation

    Directory of Open Access Journals (Sweden)

    Tiago Lukasievicz

    2018-02-01

    Full Text Available This paper proposes a control approach and supplementary controllers for the operation of a hybrid stand-alone system composed of a wind generation unit and a conventional generation unit based on synchronous generator (CGU. The proposed controllers allow the islanded or isolated operation of small power systems with predominance of wind generation. As an advantage and a paradigm shift, the DC-link voltage of the wind unit is controlled by means of a conventional synchronous generator connected to the AC grid of the system. Two supplementary controllers, added to a diesel generator (DIG and to a DC dump load (DL, are proposed to control the DC-link voltage. The wind generation unit operates in V-f control mode and the DIG operates in PQ control mode, which allows the stand-alone system to operate either in wind-diesel (WD mode or in wind-only (WO mode. The strong influence of the wind turbine speed variations in the DC-link voltage is mitigated by a low-pass filter added to the speed control loop of the wind turbine. The proposed control approach does not require the use battery bank and ultra-capacitor to control the DC-link voltage in wind generation units based on fully rated converter.

  15. Optimization of the photovoltaic-hydrogen supply system of a stand-alone remote-telecom application

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, Guillermo; Martinez, Graciano; Galvez, Jose L.; Cuevas, Raquel; Maellas, Jesus [National Institute for Aerospace Technology (INTA), Renewable Energy Department, Ctra. Ajalvir km 4, E-28850 Torrejon de Ardoz, Madrid (Spain); Gila, Raul; Bueno, Emilio [Polytechnical School - Alcala de Henares University, Electronics Department, Campus Universitario, Ctra. De Madrid-Barcelona Km 33.600, Alcala de Henares, Madrid (Spain)

    2009-07-15

    Hydrogen is considered as the optimal carrier for the surplus energy storage from renewable resources. Although hydrogen and its application in fuel cell is considered as a high-cost energy system, some cost-efficient solutions have been found for their use in stand-alone applications, which usually depend on the variability of renewable sources that have to be oversized in order to reduce their dependence on external energy sources. This paper shows the results from the simulation of several alternatives of introducing hydrogen technologies to increase the independence of a remote-telecom application fed by photovoltaic panels. Hydrogen is obtained by electrolysis and it is used in a fuel cell when the renewable energy source is not enough to maintain the stand-alone application. TRNSYS simulation environment has been used for evaluating the proposed alternatives. The results show that the best configuration option is that considering the use of hydrogen as a way to storage the surplus of radiation and the management system can vary the number of photovoltaic panels assigned to feed the hydrogen generation, the batteries or the telecom application. (author)

  16. Human microRNA target analysis and gene ontology clustering by GOmir, a novel stand-alone application.

    Science.gov (United States)

    Roubelakis, Maria G; Zotos, Pantelis; Papachristoudis, Georgios; Michalopoulos, Ioannis; Pappa, Kalliopi I; Anagnou, Nicholas P; Kossida, Sophia

    2009-06-16

    microRNAs (miRNAs) are single-stranded RNA molecules of about 20-23 nucleotides length found in a wide variety of organisms. miRNAs regulate gene expression, by interacting with target mRNAs at specific sites in order to induce cleavage of the message or inhibit translation. Predicting or verifying mRNA targets of specific miRNAs is a difficult process of great importance. GOmir is a novel stand-alone application consisting of two separate tools: JTarget and TAGGO. JTarget integrates miRNA target prediction and functional analysis by combining the predicted target genes from TargetScan, miRanda, RNAhybrid and PicTar computational tools as well as the experimentally supported targets from TarBase and also providing a full gene description and functional analysis for each target gene. On the other hand, TAGGO application is designed to automatically group gene ontology annotations, taking advantage of the Gene Ontology (GO), in order to extract the main attributes of sets of proteins. GOmir represents a new tool incorporating two separate Java applications integrated into one stand-alone Java application. GOmir (by using up to five different databases) introduces miRNA predicted targets accompanied by (a) full gene description, (b) functional analysis and (c) detailed gene ontology clustering. Additionally, a reverse search initiated by a potential target can also be conducted. GOmir can freely be downloaded BRFAA.

  17. Leadership in Dental Hygiene Degree Completion Programs: A Pilot Study Comparing Stand-Alone Leadership Courses and Leadership-Infused Curricula.

    Science.gov (United States)

    Smith, Michelle L; Gurenlian, JoAnn R; Freudenthal, Jacqueline J; Farnsworth, Tracy J

    2016-05-01

    The aim of this study was to define the extent to which leadership and leadership skills are taught in dental hygiene degree completion programs by comparing stand-alone leadership courses/hybrid programs with programs that infuse leadership skills throughout the curricula. The study involved a mixed-methods approach using qualitative and quantitative data. Semi-structured interviews were conducted with program directors and faculty members who teach a stand-alone leadership course, a hybrid program, or leadership-infused courses in these programs. A quantitative comparison of course syllabi determined differences in the extent of leadership content and experiences between stand-alone leadership courses and leadership-infused curricula. Of the 53 U.S. dental hygiene programs that offer degree completion programs, 49 met the inclusion criteria, and 19 programs provided course syllabi. Of the program directors and faculty members who teach a stand-alone leadership course or leadership-infused curriculum, 16 participated in the interview portion of the study. The results suggested that competencies related to leadership were not clearly defined or measurable in current teaching. Reported barriers to incorporating a stand-alone leadership course included overcrowded curricula, limited qualified faculty, and lack of resources. The findings of this study provide a synopsis of leadership content and gaps in leadership education for degree completion programs. Suggested changes included defining a need for leadership competencies and providing additional resources to educators such as courses provided by the American Dental Education Association and the American Dental Hygienists' Association.

  18. Experience of Future Economists' Self-Study Organization in Foreign Higher Education Institutions

    Science.gov (United States)

    Aliyev, Oktay

    2016-01-01

    The article consolidates information sources on the issues of future economists' self-study organization at foreign universities. There has been carried out the study of approaches to the interpretation of the term "self-study process" in the contemporary scientific thought abroad. There have been specified the productive ideas of…

  19. Enhancing Student Self-Study Attitude and Activity with Motivational Techniques

    Directory of Open Access Journals (Sweden)

    Kent Rhoads

    2013-09-01

    Full Text Available Research has shown that students will exhibit a positive attitude towards self-study, but that they will often fail to complete self-study activities. The purpose of this paper is to investigate positive instructor interactions and motivation of students to complete self- study activities and students’ attitudes towards self-study. Six English instructors at the University of Shizuoka created a one-semester self-access study log for use in the university self-access language laboratory in order to find out how many students would complete the log. One of the six instructors applied motivational techniques in the classroom in an effort to engender greater student self-study. Later a questionnaire was administered to 465 student participants to determine their self-study attitudes and activities. The data collected from the questionnaire and the high participation in the self- study activities suggest the positive impact the motivational actions employed by the instructor had on his students' attitudes towards self-study activities.

  20. Influence of Motivational Design on Completion Rates in Online Self-Study Pharmacy-Content Courses

    Science.gov (United States)

    Pittenger, Amy; Doering, Aaron

    2010-01-01

    Student retention rates are a constant concern in higher education, but this concern has become especially challenging as online courses become more common and there are widespread reports of low completion rates for online, self-study courses. We evaluated four self-study online pharmacy courses with a history of very high completion rates for…

  1. Developing a Pedagogy for Teaching Self-Study Research:Lessons Learned Across the Atlantic

    NARCIS (Netherlands)

    Samaras, A.; Lunenberg, M.L.

    2011-01-01

    This article reports on a collective self-study from our multiple and unique experiences of teaching self-study research in the Netherlands and the United States. Through the methodology of dialog, we merged what we learned from our individual studies which resulted in six guidelines for a pedagogy

  2. Developing a pedagogy for teaching self-study research: Lessons learned across the Atlantic

    NARCIS (Netherlands)

    Lunenberg, Mieke; Samaras, Anastasia P.

    2011-01-01

    This article reports on a collective self-study from our multiple and unique experiences of teaching self-study research in the Netherlands and the United States. Through the methodology of dialog, we merged what we learned from our individual studies which resulted in six guidelines for a pedagogy

  3. A project management approach to an ACPE accreditation self-study.

    Science.gov (United States)

    Dominelli, Angela; Iwanowicz, Susan L; Bailie, George R; Clarke, David W; McGraw, Patrick S

    2007-04-15

    In preparation for an on-site evaluation and accreditation by the American Council on Pharmaceutical Education (ACPE), the Albany College of Pharmacy employed project management techniques to complete a comprehensive self-study. A project lifecycle approach, including planning, production, and turnover phases, was used by the project's Self-Study Steering Committee. This approach, with minimal disruption to college operations, resulted in the completion of the self-study process on schedule. Throughout the project, the Steering Committee maintained a log of functions that either were executed successfully or in hindsight, could have been improved. To assess the effectiveness of the project management approach to the the self-study process, feedback was obtained from the College community through a poststudy survey. This feedback, coupled with the Steering Committee's data on possible improvements, form the basis for the lessons learned during this self-study process.

  4. A Novel Method for Fast Configuration of Energy Storage Capacity in Stand-Alone and Grid-Connected Wind Energy Systems

    Directory of Open Access Journals (Sweden)

    Haixiang Zang

    2016-12-01

    Full Text Available In this paper, a novel method is proposed and applied to quickly calculate the capacity of energy storage for stand-alone and grid-connected wind energy systems, according to the discrete Fourier transform theory. Based on practical wind resource data and power data, which are derived from the American Wind Energy Technology Center and HOMER software separately, the energy storage capacity of a stand-alone wind energy system is investigated and calculated. Moreover, by applying the practical wind power data from a wind farm in Fujian Province, the energy storage capacity for a grid-connected wind system is discussed in this paper. This method can also be applied to determine the storage capacity of a stand-alone solar energy system with practical photovoltaic power data.

  5. Clinical and radiological outcome after anterior cervical discectomy and fusion with stand-alone empty polyetheretherketone (PEEK) cages.

    Science.gov (United States)

    Shiban, Ehab; Gapon, Karina; Wostrack, Maria; Meyer, Bernhard; Lehmberg, Jens

    2016-02-01

    To evaluate long-term results after one-, two-, and three-level anterior cervical discectomy and fusion (ACDF) with stand-alone empty polyetheretherketone (PEEK) cages. We performed a retrospective review of a consecutive patient cohort that underwent ACDF with stand-alone empty PEEK cages between 2007 and 2010 with a minimum follow-up of 12 months. Radiographic follow-up included static and flexion/extension radiographs. Changes in the operated segments were measured and compared to radiographs directly after surgery. Clinical outcome was evaluated by a physical examination, pain visual analog scale (VAS), and health-related quality of life (HRQL) using the EuroQOL questionnaire (EQ-5D). Analysis of associations between fusion, subsidence, cervical alignment, and clinical outcome parameters were performed. Of 407 consecutive cases, 318 met all inclusion criteria. Follow-up data were obtained from 265 (83 %) cases. The mean age at presentation was 55 years and 139 patients were male (52 %). In the sample, 127, 125, and 13 patients had one-, two-, and three-level surgeries, respectively; 132 (49 %) presented with spondylotic cervical myelopathy and 133 (50 %) with cervical radiculopathy. Fusion was achieved in 85, 95, and 94 % of segments in one-, two-, and three-level surgeries, respectively. Non-fusion was associated with higher VAS pain levels. Radiographic adjacent segment disease (ASD) was observed in 20, 29, and 15 % in one-, two-, and three-level surgeries, respectively. ASD was associated with lower HRQL. Subsidence was observed in 25, 27, and 15 % of segments in one-, two-, and three-level surgeries, respectively. However, this had no influence on clinical outcome. Follow-up operations for symptomatic adjacent disc disease and implant failure at index level were needed in 16 (6 %) and four (1.5 %) cases, respectively. Younger age was associated with better clinical outcome. Multilevel surgery favored better myelopathy outcomes and fusion reduced overall

  6. Online retrieval of patient information by asynchronous communication between general purpose computer and stand-alone personal computer

    International Nuclear Information System (INIS)

    Tsutsumi, Reiko; Takahashi, Kazuei; Sato, Toshiko; Komatani, Akio; Yamaguchi, Koichi

    1988-01-01

    Asynchronous communication was made between host (FACOM M-340) and personal computer (OLIBETTIE S-2250) to get patient's information required for RIA test registration. The retrieval system consists of a keyboad input of six numeric codes, patient's ID, and a real time reply containing six parameters for the patient. Their identified parameters are patient's name, sex, date of birth (include area), department, and out- or inpatient. Linking this program to RIA registration program for individual patient, then, operator can input name of RIA test requested. Our simple retrieval program made a useful data network between different types of host and stand-alone personal computers, and enabled us accurate and labor-saving registration for RIA test. (author)

  7. Integration of hydrogen energy technologies in stand-alone power systems analysis of the current potential for applications

    International Nuclear Information System (INIS)

    Zoulias, E.I.; Lymberopoulos, N.; Tsoutsos, T.; Glockner, R.; Mydske, H.J.; Vosseler, I.; Gavalda, O.; Taylor, P.

    2006-01-01

    The European study entitled: 'Market Potential Analysis for Introduction of Hydrogen Energy Technology in Stand-Alone Power Systems (H-SAPS)' aimed to establish a broad understanding of the market potential for H-SAPS and provide a basis for promoting in wide scale new technological applications. The scope of the study was limited to small and medium installations, up to a few hundred kW power rating and based on RE as the primary energy source. The potential for hydrogen technology in SAPS was investigated through an assessment of the technical potential for hydrogen, the market analysis and the evaluation of external factors. The results are mostly directed towards action by governments and the research community but also industry involvement is identified. The results include targeted market research, establishment of individual cost targets, regulatory changes to facilitate alternative grid solutions, information and capacity building, focused technology research and bridging the technology gaps. (author)

  8. A soil-canopy scheme for use in a numerical model of the atmosphere: 1D stand-alone model

    Science.gov (United States)

    Kowalczyk, E. A.; Garratt, J. R.; Krummel, P. B.

    We provide a detailed description of a soil-canopy scheme for use in the CSIRO general circulation models (GCMs) (CSIRO-4 and CSIRO-9), in the form of a one-dimensional stand-alone model. In addition, the paper documents the model's ability to simulate realistic surface fluxes by comparison with mesoscale model simulations (involving more sophisticated soil and boundary-layer treatments) and observations, and the diurnal range in surface quantities, including extreme maximum surface temperatures. The sensitivity of the model to values of the surface resistance is also quantified. The model represents phase 1 of a longer-term plan to improve the atmospheric boundary layer (ABL) and surface schemes in the CSIRO GCMs.

  9. Input of biomass in stand-alone small-scale installations for power generation. Calculation of the financial gap

    International Nuclear Information System (INIS)

    Van Tilburg, X.; De Vries, H.J.; Pfeiffer, A.E.; Beekes, M.; Cleijne, J.W.

    2005-09-01

    A number of new initiatives in which bio-oil is used in stand-alone plants for power generation has been reviewed. The question to be answered is whether the reference case for stand alone biomass projects based on burning of wood chips can still be considered representative for the costs and benefits in this category. ECN, in cooperation with KEMA, have determined the financial gap between the costs and benefits of projects in which bio-oil is used in stand alone plants for power generation. The ranges and reference case for bio-oil in stand alone applications show that these projects have a substantially lower financial gap than the current reference case based on wood chips [nl

  10. Environmental impacts of producing bioethanol and biobased lactic acid from standalone and integrated biorefineries using a consequential and an attributional life cycle assessment approach.

    Science.gov (United States)

    Parajuli, Ranjan; Knudsen, Marie Trydeman; Birkved, Morten; Djomo, Sylvestre Njakou; Corona, Andrea; Dalgaard, Tommy

    2017-11-15

    This study evaluates the environmental impacts of biorefinery products using consequential (CLCA) and attributional (ALCA) life cycle assessment (LCA) approaches. Within ALCA, economic allocation method was used to distribute impacts among the main products and the coproducts, whereas within the CLCA system expansion was adopted to avoid allocation. The study seeks to answer the questions (i) what is the environmental impacts of process integration?, and (ii) do CLCA and ALCA lead to different conclusions when applied to biorefinery?. Three biorefinery systems were evaluated and compared: a standalone system producing bioethanol from winter wheat-straw (system A), a standalone system producing biobased lactic acid from alfalfa (system B), and an integrated biorefinery system (system C) combining the two standalone systems and producing both bioethanol and lactic acid. The synergy of the integration was the exchange of useful energy necessary for biomass processing in the two standalone systems. The systems were compared against a common reference flow: "1MJ EtOH +1kg LA ", which was set on the basis of products delivered by the system C. Function of the reference flow was to provide service of both fuel (bioethanol) at 99.9% concentration (wt. basis) and biochemical (biobased lactic acid) in food industries at 90% purity; both products delivered at biorefinery gate. The environmental impacts of interest were global warming potential (GWP 100 ), eutrophication potential (EP), non-renewable energy (NRE) use and the agricultural land occupation (ALO). Regardless of the LCA approach adopted, system C performed better in most of the impact categories than both standalone systems. The process wise contribution to the obtained environmental impacts also showed similar impact pattern in both approaches. The study also highlighted that the recirculation of intermediate materials, e.g. C 5 sugar to boost bioethanol yield and that the use of residual streams in the energy

  11. Epicardial, Biatrial Ablation With Integrated Uni-bipolar Radiofrequency Technology in Stand-alone Persistent Atrial Fibrillation.

    Science.gov (United States)

    Rosati, Fabrizio; Muneretto, Claudio; Merati, Elisa; Polvani, Gianluca; Moltrasio, Massimo; Tondo, Claudio; Curnis, Antonio; Cerini, Manuel; Metras, Alexandre; Bisleri, Gianluigi

    Although minimally invasive approaches for surgical treatment of stand-alone atrial fibrillation have gained popularity for the past decade, ablation technology and extensive lesion sets play a major role in the achievement of a successful procedure, especially in presence of persistent and long-standing persistent atrial fibrillation. We evaluated clinical outcomes after totally endoscopic biatrial epicardial ablation of persistent atrial fibrillation with a novel integrated uni-bipolar radiofrequency device. Forty-nine (49) consecutive patients with stand-alone atrial fibrillation underwent right-sided monolateral thoracoscopic surgical ablation with a novel integrated uni-bipolar radiofrequency energy delivery and temperature-controlled technology. Atrial fibrillation was persistent in 13 (26.5%) of 49 and long-standing persistent in 36 (73.5%) of 49 patients. Mean ± SD age was 60.6 ± 10.3 years. Median duration of atrial fibrillation was 74 months. Mean ± SD left atrial diameter was 44.7 ± 4.0 mm. Epicardial en bloc isolation of all pulmonary veins (box lesion) and additional ablation of the right atrial free wall was successfully performed via minimally invasive approach without any intraoperative and postoperative major complications. Intraoperative entrance and exit block was achieved in 77.5% (38/49) and 91.8% (45/49) of patients, respectively. Mean ± SD ablation time was 16.3 ± 4.8 minutes. No intensive care unit stay was required. Postoperative sinus rhythm was achieved in 93.8% (30/32) patients, and no pacemaker implantation was required. At 13 months, 87.7% (43/49) of patients were in sinus rhythm; 71.4% (35/49) were free from antiarrhythmic drugs and 75.5% (37/49) from oral anticoagulation. Integrated uni-bipolar radiofrequency ablation technology showed to be effective for the surgical treatment of atrial fibrillation with a total endoscopic approach. A versapolar suction device with extensive right-left atrial lesion set may further improve

  12. The Other Side of the Coin: A Self-Study of Graduate Student Exposure to International Experiences of Inclusion

    Science.gov (United States)

    Fleishman, Melissa

    2012-01-01

    This article presents a retrospective understanding of self-study by re-living a study abroad experience through critical reflection. It will explain and clarify how reflection and self-study of the personal experiences of a graduate student can enhance the meaning of inclusion. This paper begins with a brief conceptualization of self-study,…

  13. Integrated wireless sensor network and real time smart controlling and monitoring system for efficient energy management in standalone photovoltaic systems

    Science.gov (United States)

    Abou-Elnour, Ali; Thabt, A.; Helmy, S.; Kashf, Y.; Hadad, Y.; Tarique, M.; Abo-Elnor, Ossama

    2014-04-01

    In the present work, wireless sensor network and smart real-time controlling and monitoring system are integrated for efficient energy management of standalone photovoltaic system. The proposed system has two main components namely the monitoring and controlling system and the wireless communication system. LabView software has been used in the implementation of the monitoring and controlling system. On the other hand, ZigBee wireless modules have been used to implement the wireless system. The main functions of monitoring and controlling unit is to efficiently control the energy consumption form the photovoltaic system based on accurate determination of the periods of times at which the loads are required to be operated. The wireless communication system send the data from the monitoring and controlling unit to the loads at which desired switching operations are performed. The wireless communication system also continuously feeds the monitoring and controlling unit with updated input data from the sensors and from the photovoltaic module send to calculate and record the generated, the consumed, and the stored energy to apply load switching saving schemes if necessary. It has to be mentioned that our proposed system is a low cost and low power system because and it is flexible to be upgraded to fulfill additional users' requirements.

  14. Comparative response time and fault logging with a PLC and supervisory software and a standalone unit developed for recording

    International Nuclear Information System (INIS)

    Baldaconi, Ricardo H.; Costa, Fabio E. da

    2017-01-01

    The Cobalt-60 irradiator of IPEN / CNEN, a category IV facility, has a security system for inter locking doors or exposure of radioactive sources made simultaneously by a programmable logic controller (PLC) model S7-200 from Siemens and a relay logic. From a set of information, both systems work together opening doors or exposing the sources. All incoming and outgoing information are sent serially via EIA232 communication to a personal computer with Windows® platform for a supervisory program which provides the monitoring of the entire process by a synoptic table on the computer screen and is also intended to keep records of all events on the computer's hard drive. A deficiency was found for the process of sending events via serial communication (EIA232) from PLC to the supervisory program. When failure occurred in a very short time, the PLC always took the right decision, but the registration process that had to go through the Windows® timeshare lost the information. In the previous work developed a standalone electronics unit connected to the inputs and outputs of the security system, fully optocoupled to avoid any interference to the security system that records each event on a memory card. In this work, for checking the unit developed record time ability, transients incoming signals for simulating failures, were injected at security system inputs and the response time of security system, supervisory program and the autonomous unity were measured and compared. (author)

  15. Development of a Laser-Powered Dielectric Structure-Based Accelerator as a Stand-Alone Particle Source

    International Nuclear Information System (INIS)

    Yoder, R. B.; Travish, G.; Arab, E. R.; Fong, D.; Hoyer, Z.; Lacroix, U. H.; Vartanian, N.; Rosenzweig, J. B.

    2010-01-01

    An experimental program to develop and build a dielectric-based slab-symmetric structure (the micro-accelerator platform, or MAP) for generating and accelerating low-energy electrons is underway at UCLA and Manhattanville College. This optical acceleration structure is effectively a resonant cavity powered by a side-coupled laser, and has applications as a radiation source for medicine or industry. We present recent experimental and computational results on the accelerator, and progress toward its incorporation into a self-contained particle source. Such a particle source would incorporate a micron-scale electron emitter and a non-relativistic capture region to enable self-injection into the synchronous field within the accelerator. A prototype of the accelerator itself has been constructed from candidate dielectric materials using micromanufacturing techniques; the current status of the testing program is described. A novel electron emitter incorporating pyroelectric crystals with field-enhancing tips has been demonstrated to produce steady currents; the results are dependent on tip geometry, and appear suitable for injection into a microstructure. Extension of the MAP concept to non-relativistic velocities, as in the stand-alone source, requires a tapered structure that gives rise to numerous complications including beam defocusing and manufacturing challenges; approaches for addressing these complications are mentioned.

  16. Stand-alone power systems for the future: Optimal design, operation and control of solar-hydrogen energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Ulleberg, Oeystein

    1999-12-31

    This thesis gives a systematic review of the fundamentals of energy systems, the governing physical and chemical laws related to energy, inherent characteristics of energy system, and the availability of the earth`s energy. It shows clearly why solar-hydrogen systems are one of the most viable options for the future. The main subject discussed is the modelling of SAPS (Stand-Alone Power Systems), with focus on photovoltaic-hydrogen energy systems. Simulation models for a transient simulation program are developed for PV-H{sub 2} components, including models for photovoltaics, water electrolysis, hydrogen storage, fuel cells, and secondary batteries. A PV-H{sub 2} demonstration plant in Juelich, Germany, is studied as a reference plant and the models validated against data from this plant. Most of the models developed were found to be sufficiently accurate to perform short-term system simulations, while all were more than accurate enough to perform long-term simulations. Finally, the verified simulation models are used to find the optimal operation and control strategies of an existing PV-H{sub 2} system. The main conclusion is that the simulation methods can be successfully used to find optimal operation and control strategies for a system with fixed design, and similar methods could be used to find alternative system designs. 148 refs., 78 figs., 31 tabs.

  17. Power fluctuations suppression of stand-alone hybrid generation combining solar photovoltaic/wind turbine and fuel cell systems

    International Nuclear Information System (INIS)

    Ahmed, Nabil A.; Miyatake, Masafumi; Al-Othman, A.K.

    2008-01-01

    In this paper a hybrid energy system combining variable speed wind turbine, solar photovoltaic and fuel cell generation systems is presented to supply continuous power to residential power applications as stand-alone loads. The wind and photovoltaic systems are used as main energy sources while the fuel cell is used as secondary or back-up energy source. Three individual dc-dc boost converters are used to control the power flow to the load. A simple and cost effective control with dc-dc converters is used for maximum power point tracking and hence maximum power extracting from the wind turbine and the solar photovoltaic systems. The hybrid system is sized to power a typical 2 kW/150 V dc load as telecommunication power plants or ac residential power applications in isolated islands continuously throughout the year. The results show that even when the sun and wind are not available; the system is reliable and available and it can supply high-quality power to the load. The simulation results which proved the accuracy of the proposed controllers are given to demonstrate the availability of the proposed system in this paper. Also, a complete description of the management and control system is presented

  18. Comparison of Turkey’s Geographical Regions in terms of Stand-Alone PV System Design and Cost Parameters

    Directory of Open Access Journals (Sweden)

    Nevzat Onat

    2017-01-01

    Full Text Available Stand-alone photovoltaic (SAPV systems are widely used in rural areas where there is no national grid or as a precaution against power outages. In this study, technical and economic analysis of a SAPV system was carried out using meteorological data for 75 province centers in seven geographical regions of Turkey. Obtained results for each province center were separated by geographical area. The averages of the centers for each region are taken as output. A calculation algorithm based on MsExcel has been established for these operations. The analyses made with the developed algorithm are repeated for five different scenarios that they cover periods of time when a constant strong load is active for all seasons (winter, spring, summer, and autumn and all year round. The developed algorithm calculates the life-cycle cost, the unit energy cost, the electrical capacity utilization rate, the amount of generated/excess energy per month, the initial investment/replacement, and operating and maintenance (O&M costs of each element. As a result, geographical regions of Turkey are compared in terms of these outputs graphically. Further investigations may include the sale of excess energy generated, small-scale PV system cost factors parallel to the grid, and the effects of government incentives.

  19. Stand-alone power systems for the future: Optimal design, operation and control of solar-hydrogen energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Ulleberg, Oeystein

    1998-12-31

    This thesis gives a systematic review of the fundamentals of energy systems, the governing physical and chemical laws related to energy, inherent characteristics of energy system, and the availability of the earth`s energy. It shows clearly why solar-hydrogen systems are one of the most viable options for the future. The main subject discussed is the modelling of SAPS (Stand-Alone Power Systems), with focus on photovoltaic-hydrogen energy systems. Simulation models for a transient simulation program are developed for PV-H{sub 2} components, including models for photovoltaics, water electrolysis, hydrogen storage, fuel cells, and secondary batteries. A PV-H{sub 2} demonstration plant in Juelich, Germany, is studied as a reference plant and the models validated against data from this plant. Most of the models developed were found to be sufficiently accurate to perform short-term system simulations, while all were more than accurate enough to perform long-term simulations. Finally, the verified simulation models are used to find the optimal operation and control strategies of an existing PV-H{sub 2} system. The main conclusion is that the simulation methods can be successfully used to find optimal operation and control strategies for a system with fixed design, and similar methods could be used to find alternative system designs. 148 refs., 78 figs., 31 tabs.

  20. How to Recognize and Avoid Potential, Possible, or Probable Predatory Open-Access Publishers, Standalone, and Hijacked Journals.

    Science.gov (United States)

    Danevska, Lenche; Spiroski, Mirko; Donev, Doncho; Pop-Jordanova, Nada; Polenakovic, Momir

    2016-11-01

    The Internet has enabled an easy method to search through the vast majority of publications and has improved the impact of scholarly journals. However, it can also pose threats to the quality of published articles. New publishers and journals have emerged so-called open-access potential, possible, or probable predatory publishers and journals, and so-called hijacked journals. It was our aim to increase the awareness and warn scholars, especially young researchers, how to recognize these journals and how to avoid submission of their papers to these journals. Review and critical analysis of the relevant published literature, Internet sources and personal experience, thoughts, and observations of the authors. The web blog of Jeffrey Beall, University of Colorado, was greatly consulted. Jeffrey Beall is a Denver academic librarian who regularly maintains two lists: the first one, of potential, possible, or probable predatory publishers and the second one, of potential, possible, or probable predatory standalone journals. Aspects related to this topic presented by other authors have been discussed as well. Academics should bear in mind how to differentiate between trustworthy and reliable journals and predatory ones, considering: publication ethics, peer-review process, international academic standards, indexing and abstracting, preservation in digital repositories, metrics, sustainability, etc.

  1. Comparative response time and fault logging with a PLC and supervisory software and a standalone unit developed for recording

    Energy Technology Data Exchange (ETDEWEB)

    Baldaconi, Ricardo H., E-mail: ricardohovacker@hotmail.com [Escola Senai Roberto Simonsen, Educação e Tecnologia, Sao Paulo, SP (Brazil); Costa, Fabio E. da, E-mail: fecosta@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    The Cobalt-60 irradiator of IPEN / CNEN, a category IV facility, has a security system for inter locking doors or exposure of radioactive sources made simultaneously by a programmable logic controller (PLC) model S7-200 from Siemens and a relay logic. From a set of information, both systems work together opening doors or exposing the sources. All incoming and outgoing information are sent serially via EIA232 communication to a personal computer with Windows® platform for a supervisory program which provides the monitoring of the entire process by a synoptic table on the computer screen and is also intended to keep records of all events on the computer's hard drive. A deficiency was found for the process of sending events via serial communication (EIA232) from PLC to the supervisory program. When failure occurred in a very short time, the PLC always took the right decision, but the registration process that had to go through the Windows® timeshare lost the information. In the previous work developed a standalone electronics unit connected to the inputs and outputs of the security system, fully optocoupled to avoid any interference to the security system that records each event on a memory card. In this work, for checking the unit developed record time ability, transients incoming signals for simulating failures, were injected at security system inputs and the response time of security system, supervisory program and the autonomous unity were measured and compared. (author)

  2. A feasibility study of a stand-alone hybrid solar–wind–battery system for a remote island

    International Nuclear Information System (INIS)

    Ma, Tao; Yang, Hongxing; Lu, Lin

    2014-01-01

    Highlights: • A feasibility study of a hybrid solar–wind–battery system is carried out. • Techno-economic evaluation is conducted for this proposed system. • Thousands of cases are simulated to achieve an optimal system configuration. • The performance of the proposed system is analyzed in detail. • A sensitivity analysis on its load and renewable energy resource is performed. - Abstract: This paper presents a detailed feasibility study and techno-economic evaluation of a standalone hybrid solar–wind system with battery energy storage for a remote island. The solar radiation and wind data on this island in 2009 was recorded for this study. The HOMER software was employed to do the simulations and perform the techno-economic evaluation. Thousands of cases have been carried out to achieve an optimal autonomous system configuration, in terms of system net present cost (NPC) and cost of energy (COE). A detailed analysis, description and expected performance of the proposed system were presented. Moreover, the effects of the PV panel sizing, wind turbine sizing and battery bank capacity on the system’s reliability and economic performance were examined. Finally, a sensitivity analysis on its load consumption and renewable energy resource was performed to evaluate the robustness of economic analysis and identify which variable has the greatest impact on the results. The results demonstrate the techno-economic feasibility of implementing the solar–wind–battery system to supply power to this island

  3. Modeling and Experimental Test of Grid-Tied Photovoltaic Cell Emulating System in the Stand-alone Mode

    Directory of Open Access Journals (Sweden)

    Vu Minh Phap

    2017-06-01

    Full Text Available In recent decades, generation of electricity from solar arrays has been increased to meet the world's growing energy demand. However, the utilization rate of the power conditioner in the grid-tied solar power system is low because the operation of solar panels is dependent on sunlight. Thus, we studied the method that the small scale wind power generating system in size from a few hundred watts to two or three kilowatts can be connected to the grid-tied power conditioner of the solar power system for residential applications with low power ratings (single phase, size is limited to 10kW by emulating characteristic of the solar panel. In this paper, we introduce the application of the grid-tied PV cell emulating system in the stand-alone mode to improve the utilization rate of the power conditioner. The simulation and experimental test results verify that the PV cell emulating system can operate the power conditioner of the gridtied solar power system.

  4. Design and Implement a MapReduce Framework for Executing Standalone Software Packages in Hadoop-based Distributed Environments

    Directory of Open Access Journals (Sweden)

    Chao-Chun Chen

    2013-12-01

    Full Text Available The Hadoop MapReduce is the programming model of designing the auto scalable distributed computing applications. It provides developer an effective environment to attain automatic parallelization. However, most existing manufacturing systems are arduous and restrictive to migrate to MapReduce private cloud, due to the platform incompatible and tremendous complexity of system reconstruction. For increasing the efficiency of manufacturing systems with minimum modification of existing systems, we design a framework in this thesis, called MC-Framework: Multi-uses-based Cloudizing-Application Framework. It provides the simple interface to users for fairly executing requested tasks worked with traditional standalone software packages in MapReduce-based private cloud environments. Moreover, this thesis focuses on the multiuser workloads, but the default Hadoop scheduling scheme, i.e., FIFO, would increase delay under multiuser scenarios. Hence, we also propose a new scheduling mechanism, called Job-Sharing Scheduling, to explore and fairly share the jobs to machines in the MapReduce-based private cloud. Then, we prototype an experimental virtual-metrology module of a manufacturing system as a case study to verify and analysis the proposed MC-Framework. The results of our experiments indicate that our proposed framework enormously improved the time performance compared with the original package.

  5. Multi-Objective Optimal Design of Stand-Alone Hybrid Energy System Using Entropy Weight Method Based on HOMER

    Directory of Open Access Journals (Sweden)

    Jiaxin Lu

    2017-10-01

    Full Text Available Implementation of hybrid energy system (HES is generally considered as a promising way to satisfy the electrification requirements for remote areas. In the present study, a novel decision making methodology is proposed to identify the best compromise configuration of HES from a set of feasible combinations obtained from HOMER. For this purpose, a multi-objective function, which comprises four crucial and representative indices, is formulated by applying the weighted sum method. The entropy weight method is employed as a quantitative methodology for weighting factors calculation to enhance the objectivity of decision-making. Moreover, the optimal design of a stand-alone PV/wind/battery/diesel HES in Yongxing Island, China, is conducted as a case study to validate the effectiveness of the proposed method. Both the simulation and optimization results indicate that, the optimization method is able to identify the best trade-off configuration among system reliability, economy, practicability and environmental sustainability. Several useful conclusions are given by analyzing the operation of the best configuration.

  6. A compact seven switches topology and reduced DC-link capacitor size for single-phase stand-alone PV system with hybrid energy storages

    DEFF Research Database (Denmark)

    Liu, Xiong; Wang, Peng; Loh, Poh Chiang

    2011-01-01

    Single-phase stand-alone PV system is suitable for household applications in remote area. Hybrid battery/ultra-capacitor energy storage can reduce charge and discharge cycles and avoid deep discharges of battery. This paper proposes a compact seven switches structure for stand-alone PV system......, which otherwise needs nine switches configuration, inclusive of one switch for boost converter, four switches for single-phase inverter and four switches for two DC/DC converters of battery and ultra-capacitor. It is well-known that a bulky DC-link capacitor is always required to absorb second......-order harmonic current caused by single-phase inverter. In the proposed compact topology, a small size DC-link capacitor can achieve the same function through charging/discharging control of ultra-capacitor to mitigate second-order ripple current. Simulation results are provided to validate the effectiveness...

  7. SoC-Based Output Voltage Control for BESS with a Lithium-Ion Battery in a Stand-Alone DC Microgrid

    Directory of Open Access Journals (Sweden)

    Seung-Yeong Yu

    2016-11-01

    Full Text Available This paper proposes a new DC output voltage control for a battery energy storage system (BESS with a lithium-ion battery based on the state of charge (SoC. The proposed control scheme was verified through computer simulations for a typical stand-alone DC microgrid, which consists of a BESS, photovoltaic (PV panel, engine generator (EG, and DC load. A scaled hardware prototype for a stand-alone DC microgrid was set up in the lab, in which the proposed control scheme was loaded in a DSP controller. The experimental results were compared with the simulation results for performance verification. The proposed control scheme provides relatively lower variation of the DC grid voltage than the conventional droop control.

  8. Monitoring of standalone photovoltaic systems applied to rural electrification areas; Avaliacao de desempenho e identificacao de falhas em sistemas fotovoltaicos isolados aplicados a eletrificacao rural

    Energy Technology Data Exchange (ETDEWEB)

    Machado-Neto, L. V. B.; Cabral, C. V. T.; Oliveira-Filho, D.; Diniz, A. s. A. C.

    2004-07-01

    The sustainability of standalone photovoltaic systems passes through an accompaniment of the systems installed in the field. To subsidize this accompaniment it had been developed procedures for monitoring a similar system in laboratory. The standalone photovoltaic system monitored is similar to the systems installed by Companhia Energetica de Minas Gerais - CEMIG in the schools of isolated communities, inside the Solar Light Program. The system was simulated and the aims were to optimize the project and carry out a comparative study with the monitored results. The assembly procedure of the facility consisted of the implantation of the sensors, installation of acquisition boards and development of the monitoring program. The results presented here will allow the development of a program of preventive maintenance of the systems installed by CEMIG. (Author)

  9. Biomechanical comparison of a new stand-alone anterior lumbar interbody fusion cage with established fixation techniques – a three-dimensional finite element analysis

    Directory of Open Access Journals (Sweden)

    Hsieh Pang-Hsing

    2008-06-01

    Full Text Available Abstract Background Initial promise of a stand-alone interbody fusion cage to treat chronic back pain and restore disc height has not been realized. In some instances, a posterior spinal fixation has been used to enhance stability and increase fusion rate. In this manuscript, a new stand-alone cage is compared with conventional fixation methods based on the finite element analysis, with a focus on investigating cage-bone interface mechanics and stress distribution on the adjacent tissues. Methods Three trapezoid 8° interbody fusion cage models (dual paralleled cages, a single large cage, or a two-part cage consisting of a trapezoid box and threaded cylinder were created with or without pedicle screws fixation to investigate the relative importance of the screws on the spinal segmental response. The contact stress on the facet joint, slip displacement of the cage on the endplate, and rotational angle of the upper vertebra were measured under different loading conditions. Results Simulation results demonstrated less facet stress and slip displacement with the maximal contact on the cage-bone interface. A stand-alone two-part cage had good slip behavior under compression, flexion, extension, lateral bending and torsion, as compared with the other two interbody cages, even with the additional posterior fixation. However, the two-part cage had the lowest rotational angles under flexion and torsion, but had no differences under extension and lateral bending. Conclusion The biomechanical benefit of a stand-alone two-part fusion cage can be justified. This device provided the stability required for interbody fusion, which supports clinical trials of the cage as an alternative to circumferential fixations.

  10. Systematic Multi-variable H-infinity Control Design for Primary Frequency Regulation in Stand-alone Microgrids with High Penetration of Renewable Energy Sources

    OpenAIRE

    Lam , Quang Linh; Bratcu , Antoneta Iuliana; Riu , Delphine

    2016-01-01

    International audience; In this paper, a systematic design of a robust multi-variable control structure for primary frequency regulation in microgrids with high rate of renewable source penetration is proposed. The considered microgrid represents a diesel-photovoltaic-supercapacitor hybrid power generation system operating in stand-alone mode. The proposed control structure relies on a two-level architecture: classical PI-based current tracking controllers are placed on the low control level ...

  11. Techno-economic analysis of stand-alone photovoltaic/wind/battery/hydrogen systems for very small-scale applications

    Directory of Open Access Journals (Sweden)

    Stojković Saša M.

    2016-01-01

    Full Text Available The paper presents the results of a technical and economic analysis of three stand-alone hybrid power systems based on renewable energy sources which supply a specific group of low-power consumers. This particular case includes measuring sensors and obstacle lights on a meteorological mast for wind measurements requiring an uninterrupted power supply in cold climate conditions. Although these low-power (100 W measuring sensors and obstacle lights use little energy, their energy consumption is not the same as the available solar energy obtained on a daily or seasonal basis. In the paper, complementarity of renewable energy sources was analysed, as well as one of short-term lead-acid battery-based storage and seasonal, hydrogen-based (electrolyser, H2 tank, and fuel cells storage. These relatively complex power systems were proposed earlier for high-power consumers only, while this study specifically highlights the role of the hydrogen system for supplying low-power consumers. The analysis employed a numerical simulation method using the HOMER software tool. The results of the analysis suggest that solar and wind-solar systems, which involve meteorological conditions as referred to in this paper, include a relatively large number of lead-acid batteries. Additionally, the analysis suggests that the use of hydrogen power systems for supplying low power-consumers is entirely justifiable, as it significantly reduces the number of batteries (two at minimum in this particular case. It was shown that the increase in costs induced by the hydrogen system is acceptable.

  12. Energetic and financial investigation of a stand-alone solar-thermal Organic Rankine Cycle power plant

    International Nuclear Information System (INIS)

    Tzivanidis, Christos; Bellos, Evangelos; Antonopoulos, Kimon A.

    2016-01-01

    Highlights: • A stand-alone solar driven Organic Rankine Cycle is optimized parametrically. • The system is optimized energetically and financially. • Nine working fluids are tested with cyclohexane to be the most suitable. • A collecting area of 25,000 m"2 parabolic trough collectors is the optimum solution. • The maximum IRR is 13.46% and the payback period is about 9 years. - Abstract: The use of solar thermal energy for electricity production is a clean and sustainable way to cover the increasing energy needs of our society. The most mature technology for capturing solar energy in high temperature levels is the parabolic trough collectors (PTC). In this study, an Organic Rankine Cycle (ORC) coupled with PTC is analyzed parametrically in order to be optimized financially and energetically. The first step is the thermodynamic investigation of the ORC by using various working fluids. The second step is the energetic and financial investigation of the total system which includes the solar field, the storage tank and the ORC module. By testing many combinations of collecting areas and storage tank volumes, finally cyclohexane proved to be the most suitable working fluid for producing 1 MW_e_l with PTC. Specifically, in the optimum situation a solar field of 25,000 m"2 with storage tank of about 300 m"3 leads to a payback period of 9 years and to an internal rate of return (IRR) equal to 13.46%. Moreover, an economic comparison for different commercial collectors is presented, with Eurotrough ET-150 being the financially optimum solution for this case study.

  13. Preliminary design of a Brayton cycle as a standalone Decay Heat Removal system for the Gas-cooled Fast Reactor

    International Nuclear Information System (INIS)

    Epiney, A.; Mikityuk, K.; Chawla, R.; Alpy, N.; Haubensack, D.; Malo, J.Y.

    2009-01-01

    This paper reports a preliminary design study of a Brayton cycle which would be a dedicated, standalone Decay Heat Removal (DHR) loop of the Gas-cooled Fast Reactor (GFR). In comparison to the DHR reference strategy developed during the GFR pre-conceptual design phase (which was completed by the CEA at the end of 2007), the salient feature of this alternative device would be to combine the energetic autonomy of the natural convection process - which is foreseen for operation at high and medium pressures - to the efficiency of the forced convection process which is foreseen for operation down to very low pressures. An analytical model, the so-called 'Brayton scoping' model, is described in the paper. This is based on simplified thermodynamical and aerodynamical equations and was developed to highlight design choices. First simulations of the proposed device's performance during loss-of-coolant-accident (LOCA) transients have been performed using the CATHARE code, and these are also reported. Analysis of the simulation results are consistent with the first insights obtained from usage of the 'Brayton scoping' model, e.g. the turbomachine accelerates during the depressurization process to tend towards a steady rotational speed value which is inversely proportional to the pressure. For small break LOCA events, the device operates successfully as regards its safety function and delivers to the core a relatively unperturbed cooling mass flowrate as a function of pressure change. However, further studies are required for medium to large break sizes, since certain stability concerns have been met in such cases. For example, an unexpected turbomachine stoppage was induced during the transients, resulting in loss of the necessary core cooling mass flow. (author)

  14. An adaptive artificial neural network model for sizing stand-alone photovoltaic systems: Application for isolated sites in Algeria

    International Nuclear Information System (INIS)

    Mellit, A.; Benghanem, M.; Hadj Arab, A.; Guessoum, G.

    2004-07-01

    In this paper we investigate, by using an adaptive Artificial Neural Network (ANN), in order to find a suitable model for sizing Stand-Alone Photovoltaic (SAPV) systems, based on a minimum of input data. This model combines Radial Basis Function (RBF) network and Infinite Impulse Response (IIR) filter in order to accelerate the convergence of the network. For the sizing of a photovoltaic (PV) system, we need to determine the optimal sizing coefficients (K PV , K B . These coefficients allow us to determine the number of solar panels and storage batteries necessary to satisfy a given consumption, especially in isolated sites where the global solar radiation data is not always available and which are considered the most important parameters for sizing a PV system. Obtained results by classical models (analytical, numerical, analytical- numerical, B-spline function) and new models like feed-forward (MLP), radial basis function (RBF), MLP-IIR and RBF-IIR have been compared with experimental sizing coefficients in order to illustrate the accuracy of the results of the new developed model. This model has been trained by using 200 known optimal sizing coefficients corresponding to 200 locations in Algeria. In this way, the adaptive model was trained to accept and even handle a number of unusual cases, the unknown validation sizing coefficients set produced very set accurate estimation and a correlation coefficient of 98% was obtained between the calculated and that estimated by the RBF-IIR model. This result indicates that the proposed method can be successfully used for the estimation of optimal sizing coefficients of SAPV systems for any locations in Algeria, but the methodology can be generalized using different locations over the world. (author)

  15. System dynamic model and charging control of lead-acid battery for stand-alone solar PV system

    KAUST Repository

    Huang, B.J.

    2010-05-01

    The lead-acid battery which is widely used in stand-alone solar system is easily damaged by a poor charging control which causes overcharging. The battery charging control is thus usually designed to stop charging after the overcharge point. This will reduce the storage energy capacity and reduce the service time in electricity supply. The design of charging control system however requires a good understanding of the system dynamic behaviour of the battery first. In the present study, a first-order system dynamics model of lead-acid battery at different operating points near the overcharge voltage was derived experimentally, from which a charging control system based on PI algorithm was developed using PWM charging technique. The feedback control system for battery charging after the overcharge point (14 V) was designed to compromise between the set-point response and the disturbance rejection. The experimental results show that the control system can suppress the battery voltage overshoot within 0.1 V when the solar irradiation is suddenly changed from 337 to 843 W/m2. A long-term outdoor test for a solar LED lighting system shows that the battery voltage never exceeded 14.1 V for the set point 14 V and the control system can prevent the battery from overcharging. The test result also indicates that the control system is able to increase the charged energy by 78%, as compared to the case that the charging stops after the overcharge point (14 V). © 2010 Elsevier Ltd. All rights reserved.

  16. Stand-alone front-end system for high- frequency, high-frame-rate coded excitation ultrasonic imaging.

    Science.gov (United States)

    Park, Jinhyoung; Hu, Changhong; Shung, K Kirk

    2011-12-01

    A stand-alone front-end system for high-frequency coded excitation imaging was implemented to achieve a wider dynamic range. The system included an arbitrary waveform amplifier, an arbitrary waveform generator, an analog receiver, a motor position interpreter, a motor controller and power supplies. The digitized arbitrary waveforms at a sampling rate of 150 MHz could be programmed and converted to an analog signal. The pulse was subsequently amplified to excite an ultrasound transducer, and the maximum output voltage level achieved was 120 V(pp). The bandwidth of the arbitrary waveform amplifier was from 1 to 70 MHz. The noise figure of the preamplifier was less than 7.7 dB and the bandwidth was 95 MHz. Phantoms and biological tissues were imaged at a frame rate as high as 68 frames per second (fps) to evaluate the performance of the system. During the measurement, 40-MHz lithium niobate (LiNbO(3)) single-element lightweight (<;0.28 g) transducers were utilized. The wire target measure- ment showed that the -6-dB axial resolution of a chirp-coded excitation was 50 μm and lateral resolution was 120 μm. The echo signal-to-noise ratios were found to be 54 and 65 dB for the short burst and coded excitation, respectively. The contrast resolution in a sphere phantom study was estimated to be 24 dB for the chirp-coded excitation and 15 dB for the short burst modes. In an in vivo study, zebrafish and mouse hearts were imaged. Boundaries of the zebrafish heart in the image could be differentiated because of the low-noise operation of the implemented system. In mouse heart images, valves and chambers could be readily visualized with the coded excitation.

  17. Powering of an HTS dipole insert-magnet operated standalone in helium gas between 5 and 85 K

    Science.gov (United States)

    van Nugteren, J.; Kirby, G.; Bajas, H.; Bajko, M.; Ballarino, A.; Bottura, L.; Chiuchiolo, A.; Contat, P.-A.; Dhallé, M.; Durante, M.; Fazilleau, P.; Fontalva, A.; Gao, P.; Goldacker, W.; ten Kate, H.; Kario, A.; Lahtinen, V.; Lorin, C.; Markelov, A.; Mazet, J.; Molodyk, A.; Murtomäki, J.; Long, N.; Perez, J.; Petrone, C.; Pincot, F.; de Rijk, G.; Rossi, L.; Russenschuck, S.; Ruuskanen, J.; Schmitz, K.; Stenvall, A.; Usoskin, A.; Willering, G.; Yang, Y.

    2018-06-01

    This paper describes the standalone magnet cold testing of the high temperature superconducting (HTS) magnet Feather-M2.1-2. This magnet was constructed within the European funded FP7-EUCARD2 collaboration to test a Roebel type HTS cable, and is one of the first high temperature superconducting dipole magnets in the world. The magnet was operated in forced flow helium gas with temperatures ranging between 5 and 85 K. During the tests a magnetic dipole field of 3.1 T was reached inside the aperture at a current of 6.5 kA and a temperature of 5.7 K. These values are in agreement with the self-field critical current of the used SuperOx cable assembled with Sunam tapes (low-performance batch), thereby confirming that no degradation occurred during winding, impregnation, assembly and cool-down of the magnet. The magnet was quenched many tens of times by ramping over the critical current and no degradation nor training was evident. During the tests the voltage over the coil was monitored in the microvolt range. An inductive cancellation wire was used to remove the inductive component, thereby significantly reducing noise levels. Close to the quench current, drift was detected both in temperature and voltage over the coil. This drifting happens in a time scale of minutes and is a clear indication that the magnet has reached its limit. All quenches happened approximately at the same average electric field and thus none of the quenches occurred unexpectedly.

  18. Stand-alone microgrids

    NARCIS (Netherlands)

    Bauer, P.; Weldemariam, L.E.; Raijen, E.

    2011-01-01

    Abstract- A hybrid power system (HPS) which consists of diesel Genset, PV -arrays and wind turbines with energy storing and power electronic devices is discussed in this paper. An inventory of different connection topologies is made for some of the sources that generate AC power and others that

  19. A Topography of Collaboration: Methodology, Identity and Community in Self-Study of Practice Research

    Science.gov (United States)

    Hamilton, Mary Lynn; Pinnegar, Stefinee

    2013-01-01

    Through the use of the metaphoric tool of topography, two educational researchers explore the development of their understanding of collaboration in self-study of teacher education practices research. The researchers communicate their perceptions through the presentation of four topographic moments. Each topographic moment is represented by a poem…

  20. What Teachers Want: A Differentiated Technology Integration Coaching Model Examined through a Self-Study Framework

    Science.gov (United States)

    Hatten, Stephanie Hinshaw

    2014-01-01

    The purpose of this a narrative self-study is to explore the actions taken by a Technology Instructional Specialist to determine which actions are most beneficial for teachers integrating technology in the elementary classroom. The study uses interviews, observations, and journaling of events occurring with six teachers at three different…

  1. Collaborative Self-Study of Online Teaching in Early Childhood Teacher Education

    Science.gov (United States)

    Green, Nicole; Wolodko, Brenda; Stewart, Cherry; Edwards, Helen; Brooks, Margaret; Littledyke, Ros

    2013-01-01

    Six academics at a regional university in Australia engaged in collaborative research examining their teaching and learning practices, their current understandings and beliefs about teacher education pedagogy and, specifically, the online teaching and learning environments. This collegial self-study project was guided by the goal of achieving…

  2. Increasing Creativity with the Self-Studies in Basic English Classes

    Science.gov (United States)

    Yagcioglu, Ozlem

    2016-01-01

    There are many materials, books and resources for the self-studies which can be useful in the ESL and in the EFL classrooms. Choosing the ones which can make learners more creative and happier will help our students to develop their language skills in speaking, reading, writing and listening. This paper deals with the methods and approaches to…

  3. Self-Study Guide for Florida VPK Provider Improvement Plan Development

    Science.gov (United States)

    Phillips, Beth M.; Mazzeo, Debbie; Smith, Kevin

    2016-01-01

    This Self-Study Guide has been developed to support Florida Voluntary Prekindergarten Providers (VPK) who are required to complete an improvement plan process (i.e., low-performing providers). The guide has sections that can be used during both the process of selecting target areas for an improvement plan and the process of implementing new or…

  4. Learning to Teach Mathematics Specialists in a Synchronous Online Course: A Self-Study

    Science.gov (United States)

    Hjalmarson, Margret A.

    2017-01-01

    This article uses a self-study research methodology to explore teaching an online course for mathematics specialists. The course included weekly videoconferencing sessions and focused on supporting their development as mathematics coaches working with K-8 teachers to enhance mathematics teaching and learning. The central question for the…

  5. Being a Teacher Educator: Exploring Issues of Authenticity and Safety through Self-Study

    Science.gov (United States)

    Garbett, Dawn; Ovens, Alan

    2012-01-01

    The catalyst for this self-study was implementing peer-teaching in our respective science education and physical education teacher education courses. Because our students taught one another it meant we redefined our roles as teacher educators as well as the roles that our students took in the teaching and learning community. We documented and…

  6. Summer Reading Camp Self-Study Guide. REL 2015-070

    Science.gov (United States)

    Smith, Kevin G.; Foorman, Barbara R.

    2015-01-01

    This guide is designed to facilitate self-studies of planning and implementation of state-required summer reading camp programs for grade 3 students who scored at the lowest level on the state reading assessment. It provides a template for data collection and guiding questions for discussion that may improve instruction and increase the number of…

  7. Reframing Pedagogy While Teaching about Teaching Online: A Collaborative Self-Study

    Science.gov (United States)

    Fletcher, Tim; Bullock, Shawn M.

    2015-01-01

    The purpose of this paper is to use collaborative self-study to analyze and describe our experiences of teaching about teaching in a digital, online environment. Data were gathered from reflective journal entries, emails and monthly Skype calls. Our findings indicate that the perceived disembodiment of teaching and learning online affected how we…

  8. From Skepticism to Scholarship: Learning and Living Self-Study Research in a Doctoral Seminar

    Science.gov (United States)

    Gregory, Kristen H.; Diacopoulos, Mark M.; Branyon, Angela; Butler, Brandon M.

    2017-01-01

    Teacher education doctoral seminars can provide a space for students to collaborate, reflect and support each other as they transition from teacher to teacher educator. These spaces also provide a forum for the learning of new research methodologies. This collaborative self-study chronicles how one group of doctoral students learned self-study…

  9. Language Immersion in the Self-Study Mode E-Course

    Science.gov (United States)

    Sobolev, Olga

    2016-01-01

    This paper assesses the efficiency of the "Language Immersion e-Course" developed at the London School of Economics and Political Science (LSE) Language Centre. The new self-study revision e-course, promoting students' proficiency in spoken and aural Russian through autonomous learning, is based on the Michel Thomas method, and is…

  10. Time utilization rate (TUR) of NTI-PGDE Students in self-study: the ...

    African Journals Online (AJOL)

    The purpose of this study was to find out the rate of time utilization in self-study among the Post-Graduate Diploma in Education (PGDE) students of the National Teachers' Institute. A sample of forty (40) students drawn from a population of sixty (60) by simple random sampling technique was used for the study.

  11. The Development of Students’ Cognitive Self-Study While Teaching Reading in FL Training

    Directory of Open Access Journals (Sweden)

    Natalia S. Andrianova

    2017-11-01

    Full Text Available In the informational society while teaching foreign languages the development of students’ skills aimed at searching, analyzing, critical thinking, processing and using the obtained information in the productive speech activity is in demand. In this context, the problem of students’ cognitive self-study development, aimed at “revealing” knowledge while reading, is becoming increasingly important as reading while teaching foreign languages not only contributes to self-development and self-reflection, but also to the formation of a cross-cultural and linguistic personality, which is a priority of linguistic education. The solution of the above-mentioned problems has defined the aim of our research: it is the development and implementation of technologies for optimizing students’ self-study in teaching reading. In the course of our experimental work the implementation of the principle of multi-level approach in the form of five interrelated elements in teaching reading – from the level of mastering reading techniques to the level of critical reading and stylistic comprehension reading – contributed to the ultimate development and improvement of students’ constructive-creative self-study. During the experimental work while testing the effectiveness of our methods of cognitive-practical activities, we concluded that in the process of teaching foreign languages, these methods are an effective way of teaching reading, activating students’ self-study, forming linguistic creativity, which manifests itself in the ability to produce oral and written discourses based on the creative potential development of a linguistic personality. The results obtained in the experiment can be used in educational process while creating and implementing the algorithm of organizing students’ self-study while teaching foreign languages.

  12. Post-processing in cardiovascular computed tomography. Performance of a client server solution versus a stand-alone solution

    International Nuclear Information System (INIS)

    Luecke, C.; Foldyna, B.; Andres, C.; Grothoff, M.; Nitzsche, S.; Gutberlet, M.; Lehmkuhl, L.; Boehmer-Lasthaus, S.

    2014-01-01

    Purpose: To compare the performance of server-based (CSS) versus stand-alone post-processing software (ES) for the evaluation of cardiovascular CT examinations (cvCT) and to determine the crucial steps. Data of 40 patients (20 patients for coronary artery evaluation and 20 patients prior to transcatheter aortic valve implantation [TAVI]) were evaluated by 5 radiologists with CSS and ES. Data acquisition was performed using a dual-source 128-row CT unit (SOMATOM Definition Flash, Siemens, Erlangen, Germany) and a 64-row CT unit (Brilliance 64, Philips, Hamburg, Germany). The following workflow was evaluated: Data loading, aorta and coronary segmentation, curved multiplanar reconstruction (cMPR) and 3 D volume rendering technique (3D-VRT), measuring of coronary artery stenosis and planimetry of the aortic annulus. The time requirement and subjective quality for the workflow were evaluated. The coronary arteries as well as the TAVI data could be evaluated significantly faster with CSS (5.5 ± 2.9 min and 8.2 ± 4.0 min, respectively) than with ES (13.9 ± 5.2 min and 15.2 ± 10.9 min, respectively, p = 0.01). Segmentation of the aorta (CSS: 1.9 ± 2.0 min, ES: 3.7 ± 3.3 min), generating cMPR of coronaries (CSS: 0.5 ± 0.2 min, ES: 5.1 ± 2.6 min), aorta and iliac vessels (CSS: 0.5 ± 0.4 min and 0.4 ± 0.4 min, respectively, ES: 1.6 ± 0.7 min and 2.8 ± 3 min, respectively) could be performed significantly faster with CSS than with ES with higher quality of cMPR, measuring of coronary stenosis and 3D-VRT (p < 0.05). Evaluation of cvCT can be accomplished significantly faster and better with CSS than with ES. The segmentation remains the most time-consuming workflow step, so optimization of segmentation algorithms could improve performance even further.

  13. A standalone decay heat removal device for the Gas-cooled Fast Reactor for intermediate to atmospheric pressure conditions

    Energy Technology Data Exchange (ETDEWEB)

    Epiney, A., E-mail: aaron@epiney.ch [Paul Scherrer Institute PSI, Villigen (Switzerland); Ecole Polytechnique Federale EPFL, Lausanne (Switzerland); Alpy, N., E-mail: nicolas.alpy@cea.fr [CEA, DEN, Service d' Etudes des Systemes Innovants, F-13108 Saint Paul Lez Durance (France); Mikityuk, K., E-mail: konstantin.mikityuk@psi.ch [Paul Scherrer Institute PSI, Villigen (Switzerland); Chawla, R., E-mail: rakesh.chawla@psi.ch [Paul Scherrer Institute PSI, Villigen (Switzerland); Ecole Polytechnique Federale EPFL, Lausanne (Switzerland)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer An analytical model predicting Brayton cycle off-design steady states, is developed. Black-Right-Pointing-Pointer The model is used to design an autonomous decay heat removal system for the GFR. Black-Right-Pointing-Pointer Predictions of the analytical model are verified using CATHARE. Black-Right-Pointing-Pointer CATHARE code is used to simulate a set of GFR safety depressurization transients using this device. Black-Right-Pointing-Pointer Convenient turbo-machine designs exist for the targeted autonomous decay heat removal for a wide pressure range. - Abstract: This paper reports a design study for a Brayton cycle machine, which would constitute a dedicated, standalone decay heat removal (DHR) device for the Generation IV Gas-cooled Fast Reactor (GFR). In comparison to the DHR reference strategy developed by the French Commissariat a l'Energie Atomique during the GFR pre-conceptual design phase (which was completed at the end of 2007), the salient feature of this alternative device would be to combine the energetic autonomy of the natural convection process - which is foreseen for operation at high and medium pressures - with the efficiency of the forced convection process which is foreseen for operation down to very low pressures. An analytical model, the so-called 'Brayton scoping model', is described first. This is based on simplified thermodynamic and aerodynamic equations, and was developed to highlight design choices. Two different machine designs are analyzed: a Brayton loop turbo-machine working with helium, and a second one working with nitrogen, since nitrogen is the heavy gas foreseen to be injected into the primary system to enhance the natural convection under loss-of-coolant-accident (LOCA) conditions. Simulations of the steady-state and transient behavior of the proposed device have then been carried out using the CATHARE code. These serve to confirm the insights obtained from usage of the

  14. Study into the Potential and Feasibility of a Standalone Solar-Wind Hybrid Electric Energy Supply System

    Energy Technology Data Exchange (ETDEWEB)

    Bekele, Getachew

    2009-12-15

    specific to the sites in question. Based on the sunshine duration data, the monthly average daily sunshine amount for each of the places has also been computed and given in a form of plot. Through additional work on the results of the calculations, the solar energy potential has been given in the form of solar radiation plots for each of the selected sites. As expected, the results indicated an abundance of solar energy potential. It is based on the promising findings of these two energy resource potentials, wind and solar, that the feasibility study for a standalone solar-wind hybrid energy supply system has proceeded, targeting the community mentioned earlier. The hybrid system consisted of Wind turbine, Photovoltaic panel, diesel generator and a bank of batteries, with a power conditioning converter included in the system.The hybrid stand-alone supply system is intended to provide electricity toa model community of 200 families with five to six family members in each. The community is equipped with a primary load, a deferrable load, a community school and a health post. An electric load which includes lighting, water pumping, a radio receiver, and some clinical equipment has been suggested. Hybrid Optimization Model for Electric Renewables, HOMER, software has been used for the analysis. The average wind speed and average solar radiation calculated from the data for all of the selected sites has been used to input into the software. The hybrid system design is approached in three different ways. The first approach is to include within the hybrid system those components which are locally available, without giving special attention to their efficiencies and proceed with the design work. The second approach is to thoroughly search the market for the best and most efficient technological products and to select the best components for the analysis. A third approach considered in an attempt of cost minimization is to see if a self-contained type of design can be a better

  15. Self-study program on HTML browser--application to Clinical Nursing General Remarks Course.

    Science.gov (United States)

    Ochiai, N; Sota, Y; Ezumi, H

    1997-01-01

    We created a self-study program using HTML browser on the Clinical Nursing General Remarks Course, Eighty-three students each selected a published book on a personal history (written personal reflections from individuals who had undergone medical treatment and hospitalization), read it and submitted reports of their impressions of the histories. Their reports were arranged from a nursing perspective and entered on the home page of our college using HTML browser. We intended that the students would become more interested in reading of the personal histories, and that they would acquire new self-study skills and increase their interest in Internet through use of our program. In addition, we hoped that this program would encourage positive communication and mutual sharing of information. The students were able to easily refer to a personal history according to their interest from a nursing perspective. Therefore this program realized the mutual learning among students and other users.

  16. PSYCHOLOGICAL AND PEDAGOGICAL FACTORS OF STUDENT SELF-STUDY ORGANIZATION ON ACQUIRING FOREIGN LANGUAGE COMMUNICATIVE COMPETENCE

    Directory of Open Access Journals (Sweden)

    Iryna Zadorozhna

    2016-12-01

    Full Text Available Psychological and pedagogical prerequisites of student self-study organization on acquiring foreign language communicative competence have been defined and characterized. It has been proved that self-study effectiveness depends on self-regulation and motivation. The latter is amplified by creating a situation of development, modelling personally meaningful learning context aimed at creating a real product; collaborative learning, incorporating modern technologies, using problematic tasks, regular feedback, professionally-oriented learning. On the basis of scientific literature analysis it has been concluded that self-regulation of future foreign language teachers has the following structure: defining objectives, modelling meaningful conditions, action programming, results evaluation, program correction. Ways of developing self-control, self-evaluation and self-correction have been analyzed in the article. Pedagogical preconditions of effective self-study are the following: student knowledge of efficient methods and procedures of foreign language learning; selection of procedures and strategies adequate to the defined goals; an appropriate level of student information culture; ability to manage time and control results; timely correction on the basis of current control and self-control.

  17. Self-Study as an Emergent Methodology in Career and Technical Education, Adult Education and Technology: An Invitation to Inquiry

    Science.gov (United States)

    Hawley, Todd S.; Hostetler, Andrew L.

    2017-01-01

    In this manuscript, the authors explore self-study as an emerging research methodology with the potential to open up spaces of inquiry for researchers, graduate students, and teachers in a broad array of fields. They argue that the fields of career and technical education (CTE), adult education and technology can leverage self-study methodology in…

  18. Development of performance model and optimization strategy for standalone operation of CPV-hydrogen system utilizing multi-junction solar cell

    KAUST Repository

    Burhan, Muhammad; Shahzad, Muhammad Wakil; Ng, Kim Choon

    2017-01-01

    Despite highest energy potential, solar energy is only available during diurnal period with varying intensity. Therefore, owing to solar intermittency, solar energy systems need to operate in standalone configuration for steady power supply which requires reliable and sustainable energy storage. Hydrogen production has proved to be the most reliable and sustainable energy storage option for medium and long term operation. However, at the first priority, solar energy must be captured with high efficiency, in order to reduce the overall size of the system and energy storage. Multi-junction solar cells (MJCs) provide highest energy efficiency among all of the photovoltaic technologies and the concentrated photovoltaic (CPV) system concept makes their use cost effective. However, literature is lacking the performance model and optimization strategy for standalone operation of the CPV-hydrogen system. In addition, there is no commercial tool available that can analyze CPV performance, utilizing multi-junction solar cell. This paper proposes the performance model for the CPV-hydrogen systems and the multi-objective optimization strategy for its standalone operation and techno-economic analysis, using micro genetic algorithm (micro-GA). The electrolytic hydrogen production with compression storage and fuel cell, is used as energy storage system. The CPV model is verified for the experimental data of InGaP/InGaAs/Ge triple junction solar cell. An optimal CPV system design is provided for uninterrupted power supply, even under seasonal weather variations. Such approach can be easily integrated with commercial tools and the presented performance data can be used for the design of individual components of the system.

  19. Single anterior cervical discectomy and fusion (ACDF) using self- locking stand-alone polyetheretherketone (PEEK) cage: evaluation of pain and health-related quality of life.

    Science.gov (United States)

    Kapetanakis, Stylianos; Thomaidis, Tryfon; Charitoudis, George; Pavlidis, Pavlos; Theodosiadis, Panagiotis; Gkasdaris, Grigorios

    2017-09-01

    Anterior cervical discectomy and fusion (ACDF) constitutes the conventional treatment of cervical disc herniation due to degenerative disc disease (DDD). ACDF with plating presents a variety of complications postoperatively and stand-alone cages are thought to be a promising alternative. The aim of this study was firstly, to analyze prospectively collected data from a sample of patients treated with single ACDF using C-Plus self-locking stand-alone PEEK cage system, without the use of plates or screws, in order to evaluate pain levels of patients, utilizing Neck and Arm Pain scale as an expression of visual analogue scale (VAS). Secondly, we aimed to evaluate health-related quality of life, via the short-form 36 (SF-36) and Neck Disability Index (NDI). Thirty-six patients (19 male and 17 female) with mean age 49.6±7 years old who underwent successful single ACDF using self-locking stand-alone PEEK cage for symptomatic cervical DDD were selected for the study. Neck and Arm pain, as well as SF-36 and NDI were estimated preoperatively and 1, 3, 6, and 12 months postoperatively. Patients underwent preoperative and postoperative clinical, neurological and radiological evaluation. The clinical and radiological outcomes were satisfactory after a minimum 1-year follow-up. All results were statistically important (P<0.05), excluding improvement in NDI measured between 6 and 12 months. SF-36, Neck Pain, as well as Arm Pain featured gradual and constant improvement during follow-up, with best scores presenting at 12 months after surgery, while NDI reached its best at 6 months postoperatively. Generally, all scores showed improvement postoperatively during the different phases of the follow-up. Subsequently, ACDF using C-Plus cervical cage constitutes an effective method for cervical disc herniation treatment, in terms of postoperative improvement on pain levels and health-related quality of life and a safe alternative to the conventional method of treatment for cervical DDD.

  20. Segmental kyphosis after cervical interbody fusion with stand-alone polyetheretherketone (PEEK) cages: a comparative study on 2 different PEEK cages.

    Science.gov (United States)

    Kim, Chi Heon; Chung, Chun Kee; Jahng, Tae-Ahn; Park, Sung Bae; Sohn, Seil; Lee, Sungjoon

    2015-02-01

    Retrospective comparative study. Two polyetheretherketone (PEEK) cages of different designs were compared in terms of the postoperative segmental kyphosis after anterior cervical discectomy and fusion. Segmental kyphosis occasionally occurs after the use of a stand-alone cage for anterior cervical discectomy and fusion. Although PEEK material seems to have less risk of segmental kyphosis compared with other materials, the occurrence of segmental kyphosis for PEEK cages has been reported to be from 0% to 29%. There have been a few reports that addressed the issue of PEEK cage design. A total of 41 consecutive patients who underwent single-level anterior discectomy and fusion with a stand-alone cage were included. Either a round tube-type (Solis; 18 patients, S-group) or a trapezoidal tube-type (MC+; 23 patients, M-group) cage was used. The contact area between the cage and the vertebral body is larger in MC+ than in Solis, and anchoring pins were present in the Solis cage. The effect of the cage type on the segmental angle (SA) (lordosis vs. kyphosis) at postoperative month 24 was analyzed. Preoperatively, segmental lordosis was present in 12/18 S-group and 16/23 M-group patients (P=0.84). The SA was more lordotic than the preoperative angle in both groups just after surgery, with no difference between groups (P=0.39). At 24 months, segmental lordosis was observed in 9/18 S-group and 20/23 M-group patients (P=0.01). The patients in M-group were 7.83 times more likely than patients in S-group (P=0.04; odds ratio, 7.83; 95% confidence interval, 1.09-56.28) not to develop segmental kyphosis. The design of the PEEK cage used may influence the SA, and this association needs to be considered when using stand-alone PEEK cages.

  1. Development of performance model and optimization strategy for standalone operation of CPV-hydrogen system utilizing multi-junction solar cell

    KAUST Repository

    Burhan, Muhammad

    2017-09-16

    Despite highest energy potential, solar energy is only available during diurnal period with varying intensity. Therefore, owing to solar intermittency, solar energy systems need to operate in standalone configuration for steady power supply which requires reliable and sustainable energy storage. Hydrogen production has proved to be the most reliable and sustainable energy storage option for medium and long term operation. However, at the first priority, solar energy must be captured with high efficiency, in order to reduce the overall size of the system and energy storage. Multi-junction solar cells (MJCs) provide highest energy efficiency among all of the photovoltaic technologies and the concentrated photovoltaic (CPV) system concept makes their use cost effective. However, literature is lacking the performance model and optimization strategy for standalone operation of the CPV-hydrogen system. In addition, there is no commercial tool available that can analyze CPV performance, utilizing multi-junction solar cell. This paper proposes the performance model for the CPV-hydrogen systems and the multi-objective optimization strategy for its standalone operation and techno-economic analysis, using micro genetic algorithm (micro-GA). The electrolytic hydrogen production with compression storage and fuel cell, is used as energy storage system. The CPV model is verified for the experimental data of InGaP/InGaAs/Ge triple junction solar cell. An optimal CPV system design is provided for uninterrupted power supply, even under seasonal weather variations. Such approach can be easily integrated with commercial tools and the presented performance data can be used for the design of individual components of the system.

  2. Factors that can influence the economic feasibility of stand-alone and grid-connected photovoltaic systems: case studies using the software AVES-F

    International Nuclear Information System (INIS)

    Blasques, L.C.M.; Pinho, J.T.

    2004-01-01

    This paper presents case studies of economic feasibility of solar photovoltaic systems using the software AVES-F (Analysis of Economic Feasibility of Photovoltaic Systems), developed by the authors, considering cases of stand-alone and grid-connected systems. The software takes into account several factors that can influence the economic feasibility of these kind of systems, like load to be supplied, distance to the grid, the use regime of the system, applied subsidies and others. The main goal of this paper is to analyze some of these factors and to observe how they can affect the economics of PV systems for electricity generation. (authors)

  3. Design of a small scale stand-alone solar thermal co-generation plant for an isolated region in Egypt

    International Nuclear Information System (INIS)

    Abdelhady, Suzan; Borello, Domenico; Tortora, Eileen

    2014-01-01

    Highlights: • In the selected area, connection to the grid is very difficult and expensive. • The integrated unsteady CSP/ORC system, was modeled TRNSYS. • Assuming a CSP of 200,000 m 2 , 6 MW e and 21.5 MW th can be obtained. • The energy is sufficient to feed more than 3,300 rural users and two big factories. • PER = 1.43, LCOE = 1.25 USD/kW h and the GHG emissions are reduced of 7300 toe/year. - Abstract: Most of Egypt’s population is concentrated in the Nile Valley (5% of Egypt’s area), while the western desert occupies an area of 50% of the total area of Egypt with a small number of inhabitants. The New Valley is the largest governorates in Egypt which occupies 45.8% of the total area of the Country and 65% of the Western Desert and it is the least densely populated governorate in Egypt. However, New Valley has started to receive the migrated people from the Nile valley and Delta region and the demand for the energy is continuously increasing. However, the rural area in New Valley still suffers from lack of access to energy services. The very high transmission losses and costs are the main challenges for electrification in this area. Then, it is worth to investigate the opportunities for distributed energy generation. This area of Egypt receives some of the highest solar radiation in the world (up to 3000 kW h per square meters per year), making it a prime location for use of this resource. In this study, performance and economic assessment of a small scale stand-alone solar thermal co-generation plant using diathermic oil is presented. This configuration is considered as a promising and sustainable solution to provide electricity and heat to an isolated area satisfying the local loads. Parabolic trough plant has been modeled in TRNSYS simulation environment integrated with the Solar Thermal Electric Components (STEC) model library. Both solar and power cycle performances have been modeled based on the solar energy data of the plant site. The

  4. Maintaining stability of standalone Micro-Grid by employing electrical and mechanical fault ride through techniques upon fixed speed wind generation systems

    International Nuclear Information System (INIS)

    Kamel, Rashad M.

    2013-01-01

    Highlights: • This paper presented two fault ride through techniques for fixed speed wind systems. • The first technique is implemented by inserting a series resistance with the terminals of wind generator. • Second technique is performed by adapting the gear ratio to spill some mechanical power. - Abstract: This study presents two different Fault Ride Through (FRT) techniques to keep and restore stability of Fixed Speed Wind Generation system (FSWGs) installed in standalone Micro-Grid (MG). The first technique is an electrical FRT and is implemented by inserting a series resistance with the terminals of FSWGs during fault to maintain reasonable value of terminal voltage and consequently help stability restoration. The second controller is a mechanical FRT controller and is performed by change the gear ratio of wind generation systems to spill part of extracted mechanical power and consequently improving stability issue. Obtained results proved that each controller able to maintain the stability of FSWGs under the most severe disturbance conditions (400 ms three phase fault at FSWGs terminals). The first controller is faster than the second controller in restoring FSWGs stability. Superior results and performances are obtained when the two FRT techniques are employed simultaneously. Without employing any one of the two FRT techniques, FSWGs is not able to maintain or restore its stability after fault clearing. Consequently, MG will lose one of its micro-sources and cannot keep its stability during the standalone mode, unless load shedding strategy is activated. The two proposed controllers are simple, effective, and economical attractive

  5. Risk factors for subsidence in anterior cervical fusion with stand-alone polyetheretherketone (PEEK) cages: a review of 82 cases and 182 levels.

    Science.gov (United States)

    Kao, Ting-Hsien; Wu, Chen-Hao; Chou, Yu-Ching; Chen, Hsien-Te; Chen, Wen-Hsien; Tsou, Hsi-Kai

    2014-10-01

    To determine risk factors for subsidence in patients treated with anterior cervical discectomy and fusion (ACDF) and stand-alone polyetheretherketone (PEEK) cages. Records of patients with degenerative spondylosis or traumatic disc herniation resulting in radiculopathy or myelopathy between C2 and C7 who underwent ACDF with stand-alone PEEK cages were retrospectively reviewed. Cages were filled with autogenous cancellous bone harvested from iliac crest or hydroxyapatite. Subsidence was defined as a decrease of 3 mm or more of anterior or posterior disc height from that measured on the postoperative radiograph. Eighty-two patients (32 males, 50 females; 182 treatment levels) were included in the analysis. Most patients had 1-2 treatment levels (62.2 %), and 37.8 % had 3-4 treatment levels. Treatment levels were from C2-7. Of the 82 patients, cage subsidence occurred in 31 patients, and at 39 treatment levels. Multivariable analysis showed that subsidence was more likely to occur in patients with more than two treatment levels, and more likely to occur at treatment levels C5-7 than at levels C2-5. Subsidence was not associated with postoperative alignment change but associated with more disc height change (relatively oversized cage). Subsidence is associated with a greater number of treatment levels, treatment at C5-7 and relatively oversized cage use.

  6. DCE-MRI of the breast in a stand-alone setting outside a complementary strategy - results of the TK-study

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Clemens G.; Krammer, J.; Wasser, K.; Schoenberg, S.O. [University Medical Centre Mannheim, Medical Faculty Mannheim-University of Heidelberg, Institute of Clinical Radiology and Nuclear Medicine, Mannheim (Germany); Reich, C.; Kaiser, W.A. [Friedrich-Schiller-University Hospital Jena, Institute of Diagnostic and Interventional Radiology I, Jena (Germany); Dietzel, M. [Friedrich-Alexander-University Hospital Erlangen-Nuernberg, Department of Neuroradiology, Erlangen (Germany); Baltzer, P.A.T. [Medical University Vienna, Institute of Radiology and Nuclear Medicine, Vienna (Austria)

    2015-06-01

    To evaluate the accuracy of MRI of the breast (DCE-MRI) in a stand-alone setting with extended indications. According to the inclusion criteria, breast specialists were invited to refer patients to our institution for DCE-MRI. Depending on the MR findings, patients received either a follow-up or biopsy. Between 04/2006 and 12/2011 a consecutive total of 1,488 women were prospectively examined. Of 1,488 included patients, 393 patients were lost to follow-up, 1,095 patients were evaluated. 124 patients were diagnosed with malignancy by DCE-MRI (76 TP, 48 FP, 971 TN, 0 FN cases). Positive cases were confirmed by histology, negative cases by MR follow-ups or patient questionnaires over the next 5 years in 1,737 cases (sensitivity 100 %; specificity 95.2 %; PPV 61.3 %; NPV 100 %; accuracy 95.5 %). For invasive cancers only (DCIS excluded), the results were 63 TP; 27 FP; 971 TP and 0 FN (sensitivity 100 %; specificity 97.2 %; PPV 70 %; NPV 100 %; accuracy 97.5 %). The DCE-MRI indications tested imply that negative results in DCE-MRI reliably exclude cancer. The results were achieved in a stand-alone setting (single modality diagnosis). However, these results are strongly dependent on reader experience and adequate technical standards as prerequisites for optimal diagnoses. (orig.)

  7. DCE-MRI of the breast in a stand-alone setting outside a complementary strategy - results of the TK-study

    International Nuclear Information System (INIS)

    Kaiser, Clemens G.; Krammer, J.; Wasser, K.; Schoenberg, S.O.; Reich, C.; Kaiser, W.A.; Dietzel, M.; Baltzer, P.A.T.

    2015-01-01

    To evaluate the accuracy of MRI of the breast (DCE-MRI) in a stand-alone setting with extended indications. According to the inclusion criteria, breast specialists were invited to refer patients to our institution for DCE-MRI. Depending on the MR findings, patients received either a follow-up or biopsy. Between 04/2006 and 12/2011 a consecutive total of 1,488 women were prospectively examined. Of 1,488 included patients, 393 patients were lost to follow-up, 1,095 patients were evaluated. 124 patients were diagnosed with malignancy by DCE-MRI (76 TP, 48 FP, 971 TN, 0 FN cases). Positive cases were confirmed by histology, negative cases by MR follow-ups or patient questionnaires over the next 5 years in 1,737 cases (sensitivity 100 %; specificity 95.2 %; PPV 61.3 %; NPV 100 %; accuracy 95.5 %). For invasive cancers only (DCIS excluded), the results were 63 TP; 27 FP; 971 TP and 0 FN (sensitivity 100 %; specificity 97.2 %; PPV 70 %; NPV 100 %; accuracy 97.5 %). The DCE-MRI indications tested imply that negative results in DCE-MRI reliably exclude cancer. The results were achieved in a stand-alone setting (single modality diagnosis). However, these results are strongly dependent on reader experience and adequate technical standards as prerequisites for optimal diagnoses. (orig.)

  8. Through Rubrics and Scaffolded Instruction: A Programmatic Self-Study of Writing Expectations

    Directory of Open Access Journals (Sweden)

    Hanfu Mi

    2010-05-01

    Full Text Available Colleagues in a teacher education program describe their journey of programmatic self-study as they examine how they teach and assess teacher candidates’ writing in a series of three required and sequenced undergraduate literacy courses. They lead the reader through the questions they asked themselves about their instruction and their reflective process with a goal of improving teacher candidates’ technical, reflective, and creative writing. Readers are encouraged to reflect on their expectations for teacher candidates’ writing in light of instruction and assessment. Implications for teacher education are explored.

  9. Pinvox Method to Enhance Self-Study in Blended Learning: Experiences at University of Bucharest

    Directory of Open Access Journals (Sweden)

    Enrique Canessa

    2013-05-01

    Full Text Available We report results on the first large-scale trial implementation of the new Pinvox algorithm carried out at the Department of Distance Learning (DL of the University of Bucharest to encourage hundreds of Bachelor and Master DL students to perform their self-study. Pinvox is an open source tool that helps to ensure "on-line attendance” and to induce “student's attention��� through the identification of different, randomly selected, brief audio PINs embedded automatically in videos or audio files assigned to each student. We argue that checking how students watched a video lecture has many advantages in the formative assessment work.

  10. Interactive design for self-study and developing students’ critical thinking skills in electromagnetic radiation topic

    Science.gov (United States)

    Ambarwati, D.; Suyatna, A.

    2018-01-01

    The purpose of this research are to create interactive electronic school books (ESB) for electromagnetic radiation topic that can be used for self-study and increasing students’ critical thinking skills. The research method was based on the design of research and development (R&D) model of ADDIE. The research procedure is used limited the design of the product has been validated. Data source at interactive requirement analysis phase of ESB is student and high school teacher of class XII in Lampung province. The validation of interactive ESB designs is performed by experts in science education. The data of ESB interactive needs were collected using questionnaires and analyzed using quantitative descriptive. The results of the questionnaire obtained by 97% of books that are often used in the form of printed books from schools have not been interactive and foster critical thinking of students, and 55% of students stating physics books are used not meet expectations. Expectations of students in physics learning, teachers must use interactive electronic books. The results of the validation experts pointed out, the design of ESB produced is interactive, can be used for self-study, and increasing students’ critical thinking skills, which contains instruction manuals, learning objectives, learning materials, sample questions and discussion, video illustrations, animations, summaries, as well as interactive quizzes incorporating feedback exam practice and preparation for college entrance.

  11. AN APPROACH TO MANAGING UNIVERSITY STUDENTS’ SELF-STUDY BASED ON INTERDISCIPLINARY E-PROJECTS

    Directory of Open Access Journals (Sweden)

    Yu. V. Krasavina

    2017-01-01

    Full Text Available Introduction. There are two tendencies considerably allocated in educational process of the modern higher school: the increasing amount of time for independent work of students and the active introduction of the information and communication technologies (ICT which is followed by its continuous updating and improvement. The article contributes to the problem of managing competency-based and professionally-oriented self-study for future teachers; the suggested method combines the advantages of project-based learning and the use of ICT.Aim. The objective of the paper is to assess the efficacy of interdisciplinary e-project-based approach to managing university students’ self-study.Methods. To evaluate the efficacy of such innovative method as interdisciplinary e-projects, we use quantitative and qualitative assessment. A set of quantitative pre- and post-surveys are administered for students in order to evaluate their learning outcomes and competencies development. Students’ motivation and attitudes were evaluated through questionnaires, interviews and discussions. An expert group appraisal method was used to define assessment components. Results. The groups of didactic properties and ICT didactic functions are allocated and analysed. Types of educational projects are presented. Definition and characteristic of the interdisciplinary e-project are given. Results of the pedagogical experiment conducted in M. T. Kalashnikov Izhevsk State University are described; the technology of development among students of foreign-language and information-communication competences as the most important professional ones is approved.Scientific novelty. The method of interdisciplinary e-projects is offered; it involves a set of the educational-informative techniques and procedures realized in the electronic environment and directed to the solution of the interdisciplinary problem connected with types and tasks of vocational activity

  12. Grid to Standalone Transition Motion-Sensorless Dual-Inverter Control of PMSG With Asymmetrical Grid Voltage Sags and Harmonics Filtering

    DEFF Research Database (Denmark)

    Fatu, M.; Blaabjerg, Frede; Boldea, I.

    2014-01-01

    This paper describes a variable-speed motion-sensorless control system for permanent-magnet synchronous generator (PMSG) connected to grid via back-to-back inverters for wind energy generation. The grid-side inverter control system employs proportional-integral (PI) current controllers with cross...... and automatic seamless transfer method from grid connected to stand alone and vice versa. In stand-alone mode, a voltage control scheme with selective harmonic compensation is employed. The PMSG motion-sensorless control system uses an active power controller and a PLL-based observer to estimate the rotor...... and voltage harmonics compensation. While some of the aforementioned issues have been treated rather individually in previous conference publications of the authors, the present paper integrates them into a comprehensive control system of PMSG....

  13. Techno-economic assessment of FT unit for synthetic diesel production in existing stand-alone biomass gasification plant using process simulation tool

    DEFF Research Database (Denmark)

    Hunpinyo, Piyapong; Narataruksa, Phavanee; Tungkamani, Sabaithip

    2014-01-01

    For alternative thermo-chemical conversion process route via gasification, biomass can be gasified to produce syngas (mainly CO and H2). On more applications of utilization, syngas can be used to synthesize fuels through the catalytic process option for producing synthetic liquid fuels...... such as Fischer-Tropsch (FT) diesel. The embedding of the FT plant into the stand-alone based on power mode plants for production of a synthetic fuel is a promising practice, which requires an extensive adaptation of conventional techniques to the special chemical needs found in a gasified biomass. Because...... there are currently no plans to engage the FT process in Thailand, the authors have targeted that this work focus on improving the FT configurations in existing biomass gasification facilities (10 MWth). A process simulation model for calculating extended unit operations in a demonstrative context is designed...

  14. Sizing of an electrodialysis plant powered by photovoltaic standalone system; Dimensionamento de uma planta de eletrodialise acionada por sistema fotovoltaico autonomo

    Energy Technology Data Exchange (ETDEWEB)

    Juca, Sandro Cesar Silveira; Carvalho, Paulo Cesar Marques de [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Engenharia Eletrica. Campus do Pici

    2004-07-01

    This study presents a sizing and economical analysis program of a stand-alone photovoltaic powered electrodialysis plant emphasizing the combination of the electric generation capacity originating from the available solar energy in the Northeast, that is the largest from Brazil, with the electrodialysis desalination process. The electrodialysis process consists basically of transfer of cations and anions through membranes to a concentrate flow or reject. Comparing with a reverse osmosis plant is ratified that the electrodialysis process process presents one of the smallest costs and specific energy consumptions for salts concentrations up to 5,000 ppm, characterizing most of the brackish water wells of the Northeast, and can contribute to attenuate drinking water supply problem. (author)

  15. Effect of State Feedback Coupling and System Delays on the Transient Performance of Stand-Alone VSI with LC Output Filter

    DEFF Research Database (Denmark)

    Federico, de Bosio; de Sousa Ribeiro, Luiz Antonio; Freijedo Fernandez, Francisco Daniel

    2016-01-01

    The influence of state feedback coupling in the dynamics performance of power converters for stand-alone microgrids is investigated. Computation and PWM delays are the main factors that limit the achievable bandwidth of current regulators in digital implementations. In particular, the performance...... of state feedback decoupling is degraded because of these delays. Two decoupling techniques to improve the transient response of the system are investigated, named non-ideal and ideal capacitor voltage decoupling respectively. In particular, the latter solution consists in leading the capacitor voltage...... on the state feedback decoupling path in order to compensate for system delays. Practical implementation issues are discussed with reference to both the decoupling techniques. A design methodology for the voltage loop, that considers the closed loop transfer functions developed for the inner loop, is also...

  16. Design and development of self-powered sensors on wireless sensor network for standalone plant critical data management during SBO and beyond design basis events

    International Nuclear Information System (INIS)

    Aparna, J.; Dulera, I.V.; Rama Rao, A.; Vijayan, P.K.

    2015-01-01

    Advanced reactors are designed with an aim of maximum safety, optimized fuel utilization and effective system design. Safety aspects in reactor designs are being viewed for all possible vulnerabilities, and as a result, robust self-regulating passive safety features have been favored in Gen IV and advanced reactor designs. In addition to passive systems, the accidents scenarios at Fukushima indicate the dire need of reliable and stand-alone self-powered sensors, for monitoring plant critical parameters for effective damage control actions. There is a strong need for plant critical data management and situation awareness during the unavailability of all conventional power sources in a nuclear power plant, during extended station blackout (SBO) conditions. These self-powered sensors would assist the operators in managing events like SBO and help in containing any Beyond Design Basis Events (BDBE) conditions, well away from the public domain

  17. Grid parity analysis of stand-alone hybrid microgrids: A comparative study of Germany, Pakistan, South Africa and the United States

    Science.gov (United States)

    Siddiqui, Jawad M.

    Grid parity for alternative energy resources occurs when the cost of electricity generated from the source is lower than or equal to the purchasing price of power from the electricity grid. This thesis aims to quantitatively analyze the evolution of hybrid stand-alone microgrids in the US, Germany, Pakistan and South Africa to determine grid parity for a solar PV/Diesel/Battery hybrid system. The Energy System Model (ESM) and NREL's Hybrid Optimization of Multiple Energy Resources (HOMER) software are used to simulate the microgrid operation and determine a Levelized Cost of Electricity (LCOE) figure for each location. This cost per kWh is then compared with two distinct estimates of future retail electricity prices at each location to determine grid parity points. Analysis results reveal that future estimates of LCOE for such hybrid stand-alone microgrids range within the 35-55 cents/kWh over the 25 year study period. Grid parity occurs earlier in locations with higher power prices or unreliable grids. For Pakistan grid parity is already here, while Germany hits parity between the years 2023-2029. Results for South Africa suggest a parity time range of the years 2040-2045. In the US, places with low grid prices do not hit parity during the study period. Sensitivity analysis results reveal the significant impact of financing and the cost of capital on these grid parity points, particularly in developing markets of Pakistan and South Africa. Overall, the study helps conclude that variations in energy markets may determine the fate of emerging energy technologies like microgrids. However, policy interventions have a significant impact on the final outcome, such as the grid parity in this case. Measures such as eliminating uncertainty in policies and improving financing can help these grids overcome barriers in developing economies, where they may find a greater use much earlier in time.

  18. Effects of ozone as a stand-alone and coagulation-aid treatment on the reduction of trihalomethanes precursors from high DOC and hardness water.

    Science.gov (United States)

    Sadrnourmohamadi, Mehrnaz; Gorczyca, Beata

    2015-04-15

    This study investigates the effect of ozone as a stand-alone and coagulation aid on the removal of dissolved organic carbon (DOC) from the water with a high level of DOC (13.8 mgL(-1)) and calcium hardness (270 mgL(-1)) CaCO3. Natural water collected from the Assiniboine River (Manitoba, Canada) was used in this study. Effectiveness of ozone treatment was evaluated by measurement of DOC, DOC fractions, UV254, and trihalomethane formation potential (THMFP). Additionally, zeta potential and dissolved calcium concentration were measured to discern the mechanism of ozone reactions. Results indicated that 0.8 mg O3/mg DOC ozone stand-alone can cause up to 86% UV254 reduction and up to 27% DOC reduction. DOC fractionation results showed that ozone can change the composition of DOC in the water samples, converting the hydrophobic fractions into hydrophilic ones and resulting in the reduction of THMFP. Also, ozone caused a decrease in particle stability and dissolved calcium concentration. These simultaneous ozonation effects caused improved water flocculation and enhanced removal of DOC. This resulted in reduction of the coagulant dosage when ozone doses higher than 0.2 mg O3/mg DOC were applied prior to coagulation with ferric sulfate. Also, pre-ozonation-coagulation process achieved preferential THMFP removal for all of the ozone doses tested (0-0.8 mg O3/mg DOC), leading to a lower specific THMFP in pre-ozonated-coagulated waters than in the corresponding ozonated waters. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Comparison of plate-cage construct and stand-alone anchored spacer in the surgical treatment of three-level cervical spondylotic myelopathy: a preliminary clinical study.

    Science.gov (United States)

    Shi, Sheng; Liu, Zu-De; Li, Xin-Feng; Qian, Lie; Zhong, Gui-Bin; Chen, Fang-Jing

    2015-09-01

    Although stand-alone cages were advocated to be superior to plate-cage construct (PCC) because of comparable clinical outcomes and fewer plate-related complications, cage dislocation and subsidence were frequently mentioned in multilevel fusion. There are some concerns about whether these issues can be effectively prevented in multilevel anterior cervical discectomy and fusion (ACDF) by stand-alone anchored spacer (SAAS). The aim was to compare clinical outcomes, radiologic parameters, and complications of PCC and SAAS in the treatment of three-level cervical spondylotic myelopathy (CSM). This was a retrospective comparative study. A total of 38 consecutive patients with three-level CSM (ACDF with PCC, 20 patients; ACDF with SAAS, 18 patients) were reviewed. Clinical outcomes were assessed using Japanese Orthopaedic Association and Neck Disability Index. The radiologic evaluations included cervical alignment (CA), segmental angle (SA), postoperative curvature loss (PCL), and incidence of subsidence. All the aforementioned parameters were compared before and after surgery between two groups. Besides, the aforementioned results were also compared between the two groups. The complications were also recorded. The mean follow-up period was 30.3 months. No significant differences were observed in clinical outcomes between the two groups (p>.05). Additionally, no significant differences existed in fusion rate between the two groups. There were significant differences in PCL of SA and CA and correction of SA between the two groups (pSAAS group, and the potential of SAAS to reduce the incidence of postoperative dysphagia was not proven. No other complications were observed in this study. In the surgical treatment of three-level CSM, PCC is superior to SAAS in correction and maintenance of SA and avoiding cage subsidence, although the technique of ACDF with SAAS yielded encouraging clinical outcomes and high fusion rate. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. PR2ALIGN: a stand-alone software program and a web-server for protein sequence alignment using weighted biochemical properties of amino acids.

    Science.gov (United States)

    Kuznetsov, Igor B; McDuffie, Michael

    2015-05-07

    Alignment of amino acid sequences is the main sequence comparison method used in computational molecular biology. The selection of the amino acid substitution matrix best suitable for a given alignment problem is one of the most important decisions the user has to make. In a conventional amino acid substitution matrix all elements are fixed and their values cannot be easily adjusted. Moreover, most existing amino acid substitution matrices account for the average (dis)similarities between amino acid types and do not distinguish the contribution of a specific biochemical property to these (dis)similarities. PR2ALIGN is a stand-alone software program and a web-server that provide the functionality for implementing flexible user-specified alignment scoring functions and aligning pairs of amino acid sequences based on the comparison of the profiles of biochemical properties of these sequences. Unlike the conventional sequence alignment methods that use 20x20 fixed amino acid substitution matrices, PR2ALIGN uses a set of weighted biochemical properties of amino acids to measure the distance between pairs of aligned residues and to find an optimal minimal distance global alignment. The user can provide any number of amino acid properties and specify a weight for each property. The higher the weight for a given property, the more this property affects the final alignment. We show that in many cases the approach implemented in PR2ALIGN produces better quality pair-wise alignments than the conventional matrix-based approach. PR2ALIGN will be helpful for researchers who wish to align amino acid sequences by using flexible user-specified alignment scoring functions based on the biochemical properties of amino acids instead of the amino acid substitution matrix. To the best of the authors' knowledge, there are no existing stand-alone software programs or web-servers analogous to PR2ALIGN. The software is freely available from http://pr2align.rit.albany.edu.

  1. The international phase 4 validation study of the EORTC QLQ-SWB32: A stand-alone measure of spiritual well-being for people receiving palliative care for cancer

    NARCIS (Netherlands)

    Vivat, B.; Young, T. E.; Winstanley, J.; Arraras, J. I.; Black, K.; Boyle, F.; Bredart, A.; Costantini, A.; Guo, J.; Irarrazaval, M. E.; Kobayashi, K.; Kruizinga, R.; Navarro, M.; Omidvari, S.; Rohde, G. E.; Serpentini, S.; Spry, N.; van Laarhoven, H. W. M.; Yang, G. M.

    2017-01-01

    The EORTC Quality of Life Group has just completed the final phase (field-testing and validation) of an international project to develop a stand-alone measure of spiritual well-being (SWB) for palliative cancer patients. Participants (n = 451)-from 14 countries on four continents; 54% female; 188

  2. The Impact of Course Delivery Systems on Student Achievement and Sense of Community: A Comparison of Learning Community versus Stand-Alone Classroom Settings in an Open-Enrollment Inner City Public Community College

    Science.gov (United States)

    Bandyopadhyay, Pamela

    2010-01-01

    This study examined the effects of two types of course delivery systems (learning community classroom environments versus stand-alone classroom environments) on the achievement of students who were simultaneously enrolled in remedial and college-level social science courses at an inner city open-enrollment public community college. This study was…

  3. Standalone Effects of a Cognitive Behavioral Intervention Using a Mobile Phone App on Psychological Distress and Alcohol Consumption Among Japanese Workers: Pilot Nonrandomized Controlled Trial.

    Science.gov (United States)

    Hamamura, Toshitaka; Suganuma, Shinichiro; Ueda, Mami; Mearns, Jack; Shimoyama, Haruhiko

    2018-03-22

    Research that investigates standalone effects of a mobile phone-based cognitive behavioral therapy without any human contact for reducing both psychological distress and risky drinking has been advancing; however, the number of studies is still limited. A mobile phone app called Self Record that facilitates cognitive restructuring through self-monitoring of daily thoughts and activities was developed in Japan. This study conducted a nonrandomized controlled pilot trial of the Self Record app to investigate standalone effects of the intervention on psychological distress and alcohol consumption among Japanese workers. Additionally, we examined moderating effects of negative mood regulation expectancies, which are beliefs about one's ability to control one's negative mood. A quasi-experimental design with a 1-month follow-up was conducted online in Japan from February 2016 to March 2016. A research marketing company recruited participants. The selection criteria were being a Japanese full-time worker (age 20-59 years), experiencing mild to moderate psychological distress, and having some interest in self-record apps. Assignment to group was based on participants' willingness to use the app in the study. All participants completed outcome measures of negative mood regulation expectancies, positive well-being, general distress, depression, anxiety, and typical/most weekly alcohol consumption. From the recruitment, 15.65% (1083/6921) of participants met the inclusion criteria. Of these, 51.43% (557/1083) enrolled in the study: 54.9% (306/557) in the intervention group and 45.1% (251/557) in the control group. At the 1-month follow-up, 15.3% (85/557) of participants had dropped out. Intention-to-treat analyses revealed that participants in the intervention group reported increased typical drinking (η2=.009) and heavy drinking (η2=.001). Adherence to using the app was low; 64.8% (199/306) of participants in the intervention group discontinued using the app on the first

  4. A practical multi-objective design approach for optimum exhaust heat recovery from hybrid stand-alone PV-diesel power systems

    International Nuclear Information System (INIS)

    Yousefi, Moslem; Kim, Joong Hoon; Hooshyar, Danial; Yousefi, Milad; Sahari, Khairul Salleh Mohamed; Ahmad, Rodina Binti

    2017-01-01

    Highlights: • Heat recovery exchanger is designed based on practical conditions of a hybrid power system. • Off-the-grid electricity system modeling and analysis using micro-grid analysis software HOMER. • NSGA-II is used for the multi-objective design optimization task. • A new local search is proposed to incorporate the engineering knowledge in NSGA-II. • The proposed approach outperforms the existing ones. - Abstract: Integration of solar power and diesel generators (DGs) together with battery storage has proven to be an efficient choice for stand-alone power systems (SAPS). For higher energy efficiency, heat recovery from exhaust gas of the DG can also be employed to supply all or a portion of the thermal energy demand. Although the design of such heat recovery systems (HRSs) has been studied, the effect of solar power integration has not been taken into account. In this paper, a new approach for practical design of these systems based on varying engine loads is presented. Fast and elitist non-dominated sorting genetic algorithm (NSGA-II) equipped with a novel local search was used for the design process, considering conflicting objectives of annual energy recovery and total cost of the system, and six design variables. An integrated power system, designed for a remote SAPS, was used to evaluate the design approach. The optimum power supply system was first designed using the commercial software Hybrid Optimization of Multiple Energy Resources (HOMER), based on power demand and global solar energy in the region. Heat recovery design was based on the outcome of HOMER for DG hourly load, considering different power scenarios. The proposed approach improves the annual heat recovery of the PV/DG/battery system by 4%, PV/battery by 1.7%, and stand-alone DG by 1.8% when compared with a conventional design based on nominal DG load. The results prove that the proposed approach is effective and that load calculations should be taken into account prior to

  5. More than Just Playing Outside: A Self-Study on Finding My Identity as an Environmental Educator in Science Education

    Science.gov (United States)

    Gatzke, Jenna M.; Buck, Gayle A.; Akerson, Valarie L.

    2015-01-01

    The purpose of this study was to investigate the identity conflicts I was experiencing as an environmental educator entering a doctoral program in science education. My inquiry used self-study methodology with a variety of data sources, including sixteen weeks of personal journal entries, audio-recordings of four critical friend meetings, and…

  6. A Self-Study of a Thai Teacher Educator Developing a Better Understanding of PCK for Teaching about Teaching Science

    Science.gov (United States)

    Faikhamta, Chatree; Clarke, Anthony

    2013-01-01

    In this study, I, the first author as a Thai teacher educator employed self-study as a research methodology to investigate my own understandings, questions, and curiosities about pedagogical content knowledge (PCK) for teaching science student teachers and the ways I engaged student teachers in a field-based science methods course designed to help…

  7. Learning Marketing Accounting Skills in the Introductory Marketing Course: The Development, Use, and Acceptance of a Self-Study Tutorial

    Science.gov (United States)

    Chen, Yi Ju; Greenberg, Barnett; Dickson, Peter; Goodrich, Jonathan

    2012-01-01

    A self-study tutorial designed to teach, through a learning-by-doing application, how important marketing accounting is to the whole firm, and why every business graduate should have a solid understanding of marketing accounting is tested using an exam and satisfaction survey. Performance on the exam and satisfaction with the tutorial depended…

  8. Becoming a Teacher Educator: A Self-Study of the Use of Inquiry in a Mathematics Methods Course

    Science.gov (United States)

    Marin, Katherine Ariemma

    2014-01-01

    This article details the self-study of a beginning teacher educator in her first experience in teaching a mathematics methods course. The transition from teacher to teacher educator is explored through the experience of a course focused on inquiry. Inquiry is embedded within the course from two perspectives: mathematical inquiry and teaching as…

  9. Negotiating a Shared Definition of Curriculum Integration: A Self-Study of Two Teacher Educators from Different Disciplines

    Science.gov (United States)

    Hall-Kenyon, Kendra M.; Smith, Leigh K.

    2013-01-01

    The aim of this self-study was to critically consider the authors' individual thinking and practices as they worked toward a shared understanding of connecting science and literacy during instruction. As teacher educators from different disciplines, this work required them to carefully and recurrently examine their individual understandings of the…

  10. Improving the Quality of Practicum Learning: Self-Study of a Faculty Member's Role in Practicum Supervision

    Science.gov (United States)

    Russell, Tom

    2017-01-01

    This self-study of activities as a practicum supervisor in several secondary schools focuses on the supervisor's contribution to the quality of a teacher candidate's professional learning in the context of a familiar tension between on-campus courses and in-school practicum experiences. Data from both formal and informal supervisory experiences…

  11. Are Self-study Procedural Teaching Methods Effective? A Pilot Study of a Family Medicine Residency Program.

    Science.gov (United States)

    Deffenbacher, Brandy; Langner, Shannon; Khodaee, Morteza

    2017-11-01

    A family medicine residency is a unique training environment where residents are exposed to care in multiple settings, across all ages. Procedures are an integral part of family medicine practice. Family medicine residency (FMR) programs are tasked with the job of teaching these skills at a level of intensity and frequency that allows a resident to achieve competency of such skills. In an environment that is limited by work hour restrictions, self-study teaching methods are one way to ensure all residents receive the fundamental knowledge of how to perform procedures. We developed and evaluated the efficacy of a self-study procedure teaching method and procedure evaluation checklist. A self-study procedure teaching intervention was created, consisting of instructional articles and videos on three procedures. To assess the efficacy of the intervention, and the competency of the residents, pre- and postintervention procedure performance sessions were completed. These sessions were reviewed and scored using a standardized procedure performance checklist. All 24 residents participated in the study. Overall, the resident procedure knowledge increased on two of the three procedures studied, and ability to perform procedure according to expert-validated checklist improved significantly on all procedures. A self-study intervention is a simple but effective way to increase and improve procedure training in a way that fits the complex scheduling needs of a residency training program. In addition, this study demonstrates that the procedure performance checklists are a simple and reliable way to increase assessment of resident procedure performance skills in a residency setting.

  12. [Biomechanicsl evaluation of a stand-alone interbody fusion cage based on porous TiO2/glass-ceramic on the human cervical spine].

    Science.gov (United States)

    Korinth, M C; Moersch, S; Ragoss, C; Schopphoff, E

    2003-12-01

    Recently, there has been a rapid increase in the use of cervical spine interbody fusion cages, differing in design and biomaterial used, in competition to autologous iliac bone graft and bone cement (PMMA). Limited biomechanical differences in primary stability, as well as advantages and disadvantages of each cage or material have been investigated in studies, using an in vitro human cervical spine model. 20 human cervical spine specimens were tested after fusion with either a cubical stand-alone interbody fusion cage manufactured from a new porous TiO2/glass composite (Ecopore) or PMMA after discectomy. Non-destructive biomechanical testing was performed, including flexion/extension and lateral bending using a spine testing apparatus. Three-dimensional segmental range of motion (ROM) was evaluated using an ultrasound measurement system. ROM increased more in flexion/extension and lateral bending after PMMA fusion (26.5%/36.1%), then after implantation of the Ecopore-cage (8.1%/7.8%). In this first biomechanical in vitro examination of a new porous ceramic bone replacement material a) the feasibility and reproducibility of biomechanical cadaveric cervical examination and its applicability was demonstrated, b) the stability of the ceramic cage as a stand alone interbody cage was confirmed in vitro, and c) basic information and knowledge for our intended biomechanical and histological in vivo testing, after implantation of Ecopore in cervical sheep spines, were obtained.

  13. The Research on Second-Order ADRC Algorithm of Using Wind Turbine Virtual Inertia to Participate in Primary Frequency Regulation in a Small Stand-Alone Microgrid

    Directory of Open Access Journals (Sweden)

    Wang Yi

    2018-01-01

    Full Text Available In order to improve the transient stability of frequency in a small stand-alone microgrid (SSM, this paper takes a SSM composed of a direct-drive permanent magnet synchronous generator (D-PMSG and a micro gas turbine (MGT as the background and uses wind turbine generator (WTG virtual inertia (VI to participate in the primary (short-term system frequency regulation. First of all, this paper constructs a grid-connected model composed of a WTG and a MGT, analyzes the WTG virtual inertia frequency regulation mechanism, and explains the principle of proportional-differentiation (PD virtual inertia control (VIC and its shortcomings. Secondly, the paper introduces the structure principle of n-order active disturbance rejection control (ADRC and deduces the design process of second-order ADRC-VIC. Finally, through the simulation and experimental verification, comparing the frequency perturbation of without-VIC, PD-VIC, and ADRC-VIC, it is concluded that PD-VIC and ADRC-VIC both can use the WTG virtual inertia to participate in the primary frequency regulation. The frequency regulation effect of ADRC-VIC is better than PD-VIC, ADRC-VIC can extend the rotor speed recovery time and avoid overshoot, and its frequency fluctuation amplitude and settling time are obviously improved, and ADRC-VIC can effectively avoid the overshoot phenomenon of the MGT output power.

  14. Optimal Sizing of a Stand-Alone Hybrid Power System Based on Battery/Hydrogen with an Improved Ant Colony Optimization

    Directory of Open Access Journals (Sweden)

    Weiqiang Dong

    2016-09-01

    Full Text Available A distributed power system with renewable energy sources is very popular in recent years due to the rapid depletion of conventional sources of energy. Reasonable sizing for such power systems could improve the power supply reliability and reduce the annual system cost. The goal of this work is to optimize the size of a stand-alone hybrid photovoltaic (PV/wind turbine (WT/battery (B/hydrogen system (a hybrid system based on battery and hydrogen (HS-BH for reliable and economic supply. Two objectives that take the minimum annual system cost and maximum system reliability described as the loss of power supply probability (LPSP have been addressed for sizing HS-BH from a more comprehensive perspective, considering the basic demand of load, the profit from hydrogen, which is produced by HS-BH, and an effective energy storage strategy. An improved ant colony optimization (ACO algorithm has been presented to solve the sizing problem of HS-BH. Finally, a simulation experiment has been done to demonstrate the developed results, in which some comparisons have been done to emphasize the advantage of HS-BH with the aid of data from an island of Zhejiang, China.

  15. Changes in sexual behavior of HIV-infected older adults enrolled in a clinical trial of standalone group psychotherapies targeting depression

    Science.gov (United States)

    Lovejoy, Travis I.; Heckman, Timothy G.; Sikkema, Kathleen J.; Hansen, Nathan B.; Kochman, Arlene

    2014-01-01

    By 2015, one-half of all HIV-positive persons in the U.S. will be 50-plus years of age, and as many as 30% of older adults living with HIV/AIDS continue to engage in unprotected sexual intercourse. Contemporary positive prevention models often include mental health treatment as a key component of HIV prevention interventions. This secondary data analysis characterized longitudinal patterns of sexual behavior in HIV-positive older adults enrolled in a randomized controlled trial of group mental health interventions and assessed the efficacy of psychosocial treatments that targeted depression to reduce sexual risk behavior. Participants were 295 HIV-positive adults ≥ 50 years of age experiencing mild to severe depressive symptoms, randomized to one of three study conditions: a 12-session coping improvement group intervention, a 12-session interpersonal support group intervention, or individual therapy upon request. Approximately one-fifth of participants reported one or more occasions of unprotected anal or vaginal intercourse with HIV-negative sexual partners or persons of unknown HIV serostatus over the study period. Changes in sexual behavior did not vary by intervention condition, indicating that standalone treatments that target and reduce depression may be insufficient to reduce sexual risk behavior in depressed HIV-positive older adults. PMID:24668254

  16. Stand-Alone Containment Analysis of the Phébus FPT Tests with the ASTEC and the MELCOR Codes: The FPT-0 Test

    Directory of Open Access Journals (Sweden)

    Bruno Gonfiotti

    2017-01-01

    Full Text Available The integral Phébus tests were probably one of the most important experimental campaigns performed to investigate the progression of severe accidents in light water reactors. In these tests, the degradation of a PWR fuel bundle was investigated employing different control rod materials and burn-up levels in strongly or weakly oxidizing conditions. From the results of such tests, numerical codes such as ASTEC and MELCOR have been developed to describe the evolution of a severe accident. After the termination of the experimental Phébus campaign, these two codes were furthermore expanded. Therefore, the aim of the present work is to reanalyze the first Phébus test (FPT-0 employing the updated ASTEC and MELCOR versions to ensure that the new improvements introduced in such codes allow also a better prediction of these Phébus tests. The analysis focuses on the stand-alone containment aspects of this test, and the paper summarizes the main thermal-hydraulic results and presents different sensitivity analyses carried out on the aerosols and fission products behavior. This paper is part of a series of publications covering the four executed Phébus tests employing a solid PWR fuel bundle: FPT-0, FPT-1, FPT-2, and FPT-3.

  17. Methodology for predicting sequences of mean monthly clearness index and daily solar radiation data in remote areas: Application for sizing a stand-alone PV system

    Energy Technology Data Exchange (ETDEWEB)

    Mellit, A. [Department of Electronics, Institute of Sciences Engineering, Centre University of Medea, Medea 26000 (Algeria); Department of Electronics, Faculty of Science Engineering, Blida University, Blida 09000 (Algeria); Kalogirou, S.A. [Higher Technical Institute, P.O. Box 20423, Nicosia 2152 (Cyprus); Shaari, S. [Faculty of Applied Sciences, Universiti Teknologi MARA 40450 Shah Alam, Selangor (Malaysia); Salhi, H. [Department of Electronics, Faculty of Science Engineering, Blida University, Blida 09000 (Algeria); Hadj Arab, A. [Development Centre of Renewable Energy (CDER), P.O. Box 62, Bouzareah, Algiers 16000 (Algeria); Departamento de Energias Renerables, CIEMAT, Arda Complutense, 22, Madrid 28040 (Spain)

    2008-07-15

    In this paper, a suitable adaptive neuro-fuzzy inference system (ANFIS) model is presented for estimating sequences of mean monthly clearness index (anti K{sub t}) and total solar radiation data in isolated sites based on geographical coordinates. The magnitude of solar radiation is the most important parameter for sizing photovoltaic (PV) systems. The ANFIS model is trained by using a multi-layer perceptron (MLP) based on fuzzy logic (FL) rules. The inputs of the ANFIS are the latitude, longitude, and altitude, while the outputs are the 12-values of mean monthly clearness index anti K{sub t}. These data have been collected from 60 locations in Algeria. The results show that the performance of the proposed approach in the prediction of mean monthly clearness index anti K{sub t} is favorably compared to the measured values. The root mean square error (RMSE) between measured and estimated values varies between 0.0215 and 0.0235 and the mean absolute percentage error (MAPE) is less than 2.2%. In addition, a comparison between the results obtained by the ANFIS model and artificial neural network (ANN) models, is presented in order to show the advantage of the proposed method. An example for sizing a stand-alone PV system is also presented. This technique has been applied to Algerian locations, but it can be generalized for any geographical position. It can also be used for estimating other meteorological parameters such as temperature, humidity and wind speed. (author)

  18. A Study on Electric Power Smoothing System for Lead-Acid Battery of Stand-Alone Natural Energy Power System Using EDLC

    Science.gov (United States)

    Jia, Yan; Shibata, Ryosuke; Yamamura, Naoki; Ishida, Muneaki

    To resolve energy shortage and global warming problem, renewable natural resource and its power system has been gradually generalizing. However, the power fluctuation suppressing in short period and the balance control of consumption and supply in long period are two of main problems that need to be resolved urgently in natural energy power system. In Stand-alone Natural Energy Power System (SNEPS) with power energy storage devices, power fluctuation in short period is one of the main reasons that recharge cycle times increase and lead-acid battery early failure. Hence, to prolong the service life of lead-acid battery and improve power quality through suppressing the power fluctuation, we proposed a method of electric power smoothing for lead-acid battery of SNEPS using bi-directional Buck/Boost converter and Electric Double Layer Capacitor (EDLC) in this paper. According to the test data of existing SNEPS, a power fluctuation condition is selected and as an example to analyze the validity of the proposed method. The analysis of frequency characteristics indicates the power fluctuation is suppressed a desired range in the target frequency region. The experimental results of confirmed the feasibility of the proposed system and the results well satisfy the requirement of system design.

  19. A case study of a typical 2.32 kW{sub P} stand-alone photovoltaic (SAPV) in composite climate of New Delhi (India)

    Energy Technology Data Exchange (ETDEWEB)

    Chel, Arvind; Tiwari, G.N. [Center for Energy Studies (CES), Indian Institute of Technology, Hauz Khas, New Delhi 110 016 (India)

    2011-04-15

    This paper presents rigorous experimental outdoor performance of a 2.32 kW{sub P} stand-alone photovoltaic (SAPV) system in New Delhi (India) for four weather types in each month such as clear, hazy, partially cloudy/foggy and fully cloudy/foggy weather conditions respectively. The daily power generated from the existing SAPV system was experimentally found in the range of 4-6 kW h/day depending on the prevailing sky conditions. The number of days and daily power generated corresponding to four weather types in each month were used to determine monthly and subsequently annual power generation from the existing SAPV system. There are three daily load profiles with and without earth to air heat exchanger suitable for three seasons like summer (3.75-6.15 kW h/day), winter (2.79-5.19 kW h/day) and rainy (3.75 kW h/day). The hourly efficiency of the SAPV system components are determined and presented in this paper. The life cycle cost (LCC) analysis for the existing typical SAPV system is carried out to determine unit cost of electricity. The effect of annual degradation rate of PV system efficiency is also presented in this paper. The energy production factor (EPF) and the energy payback time (EPBT) of the SAPV system was also determined and presented in this paper. (author)

  20. CRionScan: A stand-alone real time controller designed to perform ion beam imaging, dose controlled irradiation and proton beam writing

    Science.gov (United States)

    Daudin, L.; Barberet, Ph.; Serani, L.; Moretto, Ph.

    2013-07-01

    High resolution ion microbeams, usually used to perform elemental mapping, low dose targeted irradiation or ion beam lithography needs a very flexible beam control system. For this purpose, we have developed a dedicated system (called “CRionScan”), on the AIFIRA facility (Applications Interdisciplinaires des Faisceaux d'Ions en Région Aquitaine). It consists of a stand-alone real-time scanning and imaging instrument based on a Compact Reconfigurable Input/Output (Compact RIO) device from National Instruments™. It is based on a real-time controller, a Field Programmable Gate Array (FPGA), input/output modules and Ethernet connectivity. We have implemented a fast and deterministic beam scanning system interfaced with our commercial data acquisition system without any hardware development. CRionScan is built under LabVIEW™ and has been used on AIFIRA's nanobeam line since 2009 (Barberet et al., 2009, 2011) [1,2]. A Graphical User Interface (GUI) embedded in the Compact RIO as a web page is used to control the scanning parameters. In addition, a fast electrostatic beam blanking trigger has been included in the FPGA and high speed counters (15 MHz) have been implemented to perform dose controlled irradiation and on-line images on the GUI. Analog to Digital converters are used for the beam current measurement and in the near future for secondary electrons imaging. Other functionalities have been integrated in this controller like LED lighting using Pulse Width Modulation and a “NIM Wilkinson ADC” data acquisition.

  1. CRionScan: A stand-alone real time controller designed to perform ion beam imaging, dose controlled irradiation and proton beam writing

    Energy Technology Data Exchange (ETDEWEB)

    Daudin, L., E-mail: daudin@cenbg.in2p3.fr [Université Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Barberet, Ph.; Serani, L.; Moretto, Ph. [Université Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France)

    2013-07-01

    High resolution ion microbeams, usually used to perform elemental mapping, low dose targeted irradiation or ion beam lithography needs a very flexible beam control system. For this purpose, we have developed a dedicated system (called “CRionScan”), on the AIFIRA facility (Applications Interdisciplinaires des Faisceaux d’Ions en Région Aquitaine). It consists of a stand-alone real-time scanning and imaging instrument based on a Compact Reconfigurable Input/Output (Compact RIO) device from National Instruments™. It is based on a real-time controller, a Field Programmable Gate Array (FPGA), input/output modules and Ethernet connectivity. We have implemented a fast and deterministic beam scanning system interfaced with our commercial data acquisition system without any hardware development. CRionScan is built under LabVIEW™ and has been used on AIFIRA’s nanobeam line since 2009 (Barberet et al., 2009, 2011) [1,2]. A Graphical User Interface (GUI) embedded in the Compact RIO as a web page is used to control the scanning parameters. In addition, a fast electrostatic beam blanking trigger has been included in the FPGA and high speed counters (15 MHz) have been implemented to perform dose controlled irradiation and on-line images on the GUI. Analog to Digital converters are used for the beam current measurement and in the near future for secondary electrons imaging. Other functionalities have been integrated in this controller like LED lighting using Pulse Width Modulation and a “NIM Wilkinson ADC” data acquisition.

  2. Stand-alone photovoltaic (PV) integrated with earth to air heat exchanger (EAHE) for space heating/cooling of adobe house in New Delhi (India)

    International Nuclear Information System (INIS)

    Chel, Arvind; Tiwari, G.N.

    2010-01-01

    This paper deals with an experimental outdoor annual performance evaluation of 2.32 kW P photovoltaic (PV) power system located at solar energy park in New Delhi composite climatic conditions. This PV system operates the daily electrical load nearly 10 kW h/day which comprises of various applications such as electric air blower of an earth to air heat exchanger (EAHE) used for heating/cooling of adobe house, ceiling fan, fluorescent tube-light, computer, submersible water pump, etc. The outdoor efficiencies, power generated and lost in PV system components were determined using hourly experimental measured data for 1 year on typical clear day in each month. These realistic data are useful for design engineers for outdoor assessment of PV system components. The energy conservation, mitigation of CO 2 emission and carbon credit potential of the existing PV integrated EAHE system is presented in this paper. Also, the energy payback time (EPBT) and unit cost of electricity were determined for both stand-alone PV (SAPV) and building roof integrated PV (BIPV) systems.

  3. Direct Flux Control for Stand-Alone Operation Brushless Doubly Fed Induction Generators Using a Resonant-Based Sliding-Mode Control Approach

    Directory of Open Access Journals (Sweden)

    Kai Ji

    2018-04-01

    Full Text Available In this paper, a novel voltage control strategy for stand-alone operation brushless doubly fed induction generators for variable speed constant frequency wind energy conversion systems was presented and discussed. Based on the model of the power generation system, the proposed direct flux control strategy employs a nonlinear reduced-order generalized integrator-based resonant sliding-mode control approach to directly calculate and regulate the output value of converter which the control winding stator requires so as to eliminate its instantaneous errors, without involving any synchronous rotating coordinate transformations. The stability, robustness and convergence capability of the proposed control strategy were described and analyzed. Owing to the fact no additional current control inner loops are involved, the system configuration is therefore simplified and the dynamic performance enhanced. A constant converter switching frequency was achieved by using space vector pulse width modulation, which reduces the harmonics of the generator terminal voltage. In addition, the feasibility and validity of the proposed scheme is verified by experiments, and excellent steady and transient performance is achieved.

  4. The third space: The use of self-study to examine the culture of a science classroom

    Science.gov (United States)

    Magee, Dashia M.

    Science educators are in the position to create bridges between their students and the world of science (Aikenhead, 1996, 1999). This connection has often been described as the third space (Bhabha, 1994; Moje, Collazo, Carrillo, & Marx, 2001; Wallace, 2004), which is represented as a combination or a meeting of the students' world and the world of science. In this study, I examined my role in creating the third space through the use of self-study. Self-study is a form of research, educators use to understand their practice (Austin & Senese, 2004; Loughran, 2004; Northfield & Loughran, 1996). It is a means of describing, analyzing, and interpreting a teacher's actions within his or her classroom (Tidwell, 2002). The focal point of this self-study is to understand my actions found within my past and present teaching experiences and the underlying beliefs that are expressed through those actions. In this self-study, I collected data from my life history, classroom observations, and member check interview. My life history described my influences that shaped my philosophy of teaching and learning, while the classroom observations provided a means of understanding my interactions with the science curriculum and my English Language Learner (ELL) students. And finally, a member check focus group interview occurred to confirm the results occurring in the classroom observations. Once the data were collected, I used grounded theory methods to analyze my results and answer the research questions. This self-study became the means of exploring my philosophy of teaching and learning and my teaching practices as they occurred in an ELL science classroom. I examined my own practice through a comparison between my past experiences and my current teaching situation and through this exploration, I identified my actions and the beliefs associated with those actions as they informed my teaching practices.

  5. ASSESSING SELF-STUDY WORK’S SIGNIFICANT SKILLS FOR SUCCESSFUL LEARNING IN THE HIGHER SCHOOL

    Directory of Open Access Journals (Sweden)

    Galina V. Milovanova

    2017-06-01

    Full Text Available Introduction: the problem of organizing students’ independent work/self-study is not new, but the changes in the higher school for the last two decades show that the experience accumulated in the traditional educational model can be applied only when it is processed in the present-day conditions. The article analyses the innovative component of the educational process in terms of a significant increase in the volume of compulsory independent work in the university. Particular attention is paid to determining the levels of the formation of skills for independent work in terms of students’ readiness for its implementa¬tion. The aim of the research is to identify the most significant skills of independent work for successful study at the university. Materials and Methods: the research is based on general scholarly methods: analysis, comparison, generalisation. A questionnaire survey was carried out and a correlation analysis of the results was presented. The mathematical statistics methods in Excel application were u sed for processing the survey data. Results: the article focused on the relevance of formation the students’ ability to work independently in the learning process. Requirements for professionals recognize the need for knowledge and skills, but more importantly, the ability and readiness to complete this knowledge and be in a state of continuous education and self-education. In turn, readiness to self-education cannot exist without independent work. The ratio of students to work independently and their skills’ levels in this area of the gnostic, design, structural, organisational and communicative blocks were identified because o f the research. Discussion and Conclusions: the levels of the formation of the skills for independent work influence on the success of the learning. There is a correlation between indicators of achievement and the ability to work independently. Organisation and communication skills have significant

  6. Further development of LLNA:DAE method as stand-alone skin-sensitization testing method and applied for evaluation of relative skin-sensitizing potency between chemicals.

    Science.gov (United States)

    Yamashita, Kunihiko; Shinoda, Shinsuke; Hagiwara, Saori; Itagaki, Hiroshi

    2015-04-01

    To date, there has been no well-established local lymph node assay (LLNA) that includes an elicitation phase. Therefore, we developed a modified local lymph node assay with an elicitation phase (LLNA:DAE) to discriminate true skin sensitizers from chemicals that gave borderline positive results and previously reported this assay. To develop the LLNA:DAE method as a useful stand-alone testing method, we investigated the complete procedure for the LLNA:DAE method using hexyl cinnamic aldehyde (HCA), isoeugenol, and 2,4-dinitrochlorobenzene (DNCB) as test compounds. We defined the LLNA:DAE procedure as follows: in the dose-finding test, four concentrations of chemical applied to dorsum of the right ear on days 1, 2, and 3 and dorsum of both ears on day 10. Ear thickness and skin irritation score were measured on days 1, 3, 5, 10, and 12. Local lymph nodes were excised and weighed on day 12. The test dose for the primary LLNA:DAE study was selected as the dose that gave the highest left ear lymph node weight in the dose-finding study, or the lowest dose that produced a left ear lymph node of over 4 mg. This procedure was validated using nine different chemicals. Furthermore, qualitative relationship was observed between the degree of elicitation response in the left ear lymph node and the skin sensitizing potency of 32 chemicals tested in this study and the previous study. These results indicated that LLNA:DAE method was as first LLNA method that was able to evaluate the skin sensitizing potential and potency in elicitation response.

  7. Effects of a stand-alone web-based electronic screening and brief intervention targeting alcohol use in university students of legal drinking age: A randomized controlled trial.

    Science.gov (United States)

    Ganz, Thomas; Braun, Michael; Laging, Marion; Schermelleh-Engel, Karin; Michalak, Johannes; Heidenreich, Thomas

    2018-02-01

    Many intervention efforts targeting student drinking were developed to address US college students, which usually involves underage drinking. It remains unclear, if research evidence from these interventions is generalizable to university and college students of legal drinking age, e.g., in Europe. To evaluate the effectiveness of a translated and adapted version of the eCHECKUP TO GO, applied as stand-alone web-based electronic screening and brief intervention (e-SBI), in German university students at risk for hazardous drinking. A fully automated web-based two-arm parallel-group randomized controlled trial was conducted. Participants were randomized to an e-SBI or assessment-only (AO) condition. The current paper analyzed students with baseline AUDIT-C scores ≥3 for women and ≥4 for men (sample at baseline: e-SBI [n=514], AO [n=467]; 3-month follow-up: e-SBI [n=194], AO [n=231]; 6-month follow-up: e-SBI [n=146], AO [n=200]). The primary outcome was prior four weeks' alcohol consumption. Secondary outcomes were frequency of heavy drinking occasions, peak blood alcohol concentration, and number of alcohol-related problems. Mixed linear model analyses revealed significant interaction effects between groups and time points on the primary outcome after 3 and 6months. Compared to students in the AO condition, students in the e-SBI condition reported consuming 4.11 fewer standard drinks during the previous four weeks after 3months, and 4.78 fewer standard drinks after 6months. Mixed results were found on secondary outcomes. The results indicate that evidence on and knowledge of web-based e-SBIs based on US college student samples is transferable to German university students of legal drinking age. However, knowledge of what motivates students to complete programs under voluntary conditions, although rare, is needed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Associate in Occupational Studies, Culinary Arts. Self-Study Report Presented to the Accrediting Commission of the American Culinary Federation Educational Institute.

    Science.gov (United States)

    Schenectady County Community Coll., Schenectady, NY.

    This report is the self-study of the Associate in Occupational Studies (AOS) in Culinary Arts program offered by the Hotel, Culinary Arts, and Tourism Department at Schenectady County Community College (New York). The self-study was conducted to support the department's application for initial accreditation of the Culinary Arts program with the…

  9. Stand-alone containment analysis of Phébus FPT tests with ASTEC and MELCOR codes: the FPT-2 test.

    Science.gov (United States)

    Gonfiotti, Bruno; Paci, Sandro

    2018-03-01

    During the last 40 years, many studies have been carried out to investigate the different phenomena occurring during a Severe Accident (SA) in a Nuclear Power Plant (NPP). Such efforts have been supported by the execution of different experimental campaigns, and the integral Phébus FP tests were probably some of the most important experiments in this field. In these tests, the degradation of a Pressurized Water Reactor (PWR) fuel bundle was investigated employing different control rod materials and burn-up levels in strongly or weakly oxidizing conditions. From the findings on these and previous tests, numerical codes such as ASTEC and MELCOR have been developed to analyze the evolution of a SA in real NPPs. After the termination of the Phébus FP campaign, these two codes have been furthermore improved to implement the more recent findings coming from different experimental campaigns. Therefore, continuous verification and validation is still necessary to check that the new improvements introduced in such codes allow also a better prediction of these Phébus tests. The aim of the present work is to re-analyze the Phébus FPT-2 test employing the updated ASTEC and MELCOR code versions. The analysis focuses on the stand-alone containment aspects of this test, and three different spatial nodalizations of the containment vessel (CV) have been developed. The paper summarizes the main thermal-hydraulic results and presents different sensitivity analyses carried out on the aerosols and fission products (FP) behavior. When possible, a comparison among the results obtained during this work and by different authors in previous work is also performed. This paper is part of a series of publications covering the four Phébus FP tests using a PWR fuel bundle: FPT-0, FPT-1, FPT-2, and FPT-3, excluding the FPT-4 one, related to the study of the release of low-volatility FP and transuranic elements from a debris bed and a pool of melted fuel.

  10. Stand-alone containment analysis of Phébus FPT tests with ASTEC and MELCOR codes: the FPT-2 test

    Directory of Open Access Journals (Sweden)

    Bruno Gonfiotti

    2018-03-01

    Full Text Available During the last 40 years, many studies have been carried out to investigate the different phenomena occurring during a Severe Accident (SA in a Nuclear Power Plant (NPP. Such efforts have been supported by the execution of different experimental campaigns, and the integral Phébus FP tests were probably some of the most important experiments in this field. In these tests, the degradation of a Pressurized Water Reactor (PWR fuel bundle was investigated employing different control rod materials and burn-up levels in strongly or weakly oxidizing conditions. From the findings on these and previous tests, numerical codes such as ASTEC and MELCOR have been developed to analyze the evolution of a SA in real NPPs. After the termination of the Phébus FP campaign, these two codes have been furthermore improved to implement the more recent findings coming from different experimental campaigns. Therefore, continuous verification and validation is still necessary to check that the new improvements introduced in such codes allow also a better prediction of these Phébus tests. The aim of the present work is to re-analyze the Phébus FPT-2 test employing the updated ASTEC and MELCOR code versions. The analysis focuses on the stand-alone containment aspects of this test, and three different spatial nodalizations of the containment vessel (CV have been developed. The paper summarizes the main thermal-hydraulic results and presents different sensitivity analyses carried out on the aerosols and fission products (FP behavior. When possible, a comparison among the results obtained during this work and by different authors in previous work is also performed. This paper is part of a series of publications covering the four Phébus FP tests using a PWR fuel bundle: FPT-0, FPT-1, FPT-2, and FPT-3, excluding the FPT-4 one, related to the study of the release of low-volatility FP and transuranic elements from a debris bed and a pool of melted fuel. Keywords: Safety

  11. Performance evaluation of a stand-alone solar dish Stirling system for power generation suitable for off-grid rural electrification

    International Nuclear Information System (INIS)

    Kadri, Y.; Hadj Abdallah, H.

    2016-01-01

    Highlights: • Estimation of the output temperature reached by 2 m parabolic dish. • Output power estimation for uncontrollable load was done using Matlab®. • Validation of the proposed system under Tunisian conditions for rural electrification. - Abstract: The development of green power generation such as solar systems that have become a great interest for several countries especially for Tunisia as it presents a significant solar potential. For this purpose, this research has investigated the feasibility and the performance of standalone solar dish/Stirling micro generation plant for rural electrification. The considered hybrid system includes solar dish/Stirling engine, permanent magnet synchronous generator and a storage battery. To start with, thermal modeling and simulation have been carried out using Matlab® for the solar-driven Stirling heat engine system composed of an Alpha Stirling engine, a solar collector and a receiver, in which the radiation, convection, conduction and radiation heat loss have been taken into consideration for the selected design. For numerical validation of the receiver’s thermal model, simulation results were compared with experimental measurements reported for the EURODISH system with a reasonable degree of agreement. Second, the generated torque driving the generator has been estimated by the Adiabatic model of URIELI based on the classical fourth-order Runge-Kutta. In order for an autonomous control, the dish generator is connected to the load via power electronic converters where the bidirectional power flow is possible by the use of two voltage source converters in a back-to-back configuration. They are referred to as Stirling/generator side converter and load side inverter, both are oriented control by space vector pulse width modulation. In this context, the Stirling side converter is used to adjust the synchronous generator while the inverter controls the power flow between the direct current bus and the

  12. Alcatel-Lucent Service Routing Architect (SRA) self-study guide preparing for the BGP, VPRN and Multicast exams

    CERN Document Server

    Warnock, Glenn; Shaheen, Ghassan

    2015-01-01

    A comprehensive resource for professionals preparing for Alcatel-Lucent Service Routing Architect (SRA) certification Networking professionals are taking note of Alcatel-Lucent and its quick ascent in the networking and telecom industries. IP networking professionals looking for a comprehensive guide to obtaining the Alcatel-Lucent Service Routing Architect (SRA) certification will be pleased to learn of this new publication, Alcatel-Lucent Service Routing Architect (SRA) Self-Study Guide: Preparing for the BGP, VPRN and Multicast Exams. The book comprises approximately 2,600 pages of print a

  13. Alcatel-Lucent Network Routing Specialist II (NRS II) Self-Study Guide Preparing for the NRS II Certification Exams

    CERN Document Server

    Warnock, Glenn

    2011-01-01

    The definitive resource for the NRS II exams—three complete courses in a book Alcatel-Lucent is a world leader in designing and developing scalable systems for service providers. If you are a network designer or operator who uses Alcatel-Lucent's 7750 family of service routers, prepare for certification as an A-L network routing specialist with this complete self-study course. You'll get thorough preparation for the NRS II exams while you learn to build state-of-the-art, scalable IP/MPLS-based service networks. The book provides you with an in-depth understanding of the protocols and tec

  14. Search Improvement Process-Chaotic Optimization-Particle Swarm Optimization-Elite Retention Strategy and Improved Combined Cooling-Heating-Power Strategy Based Two-Time Scale Multi-Objective Optimization Model for Stand-Alone Microgrid Operation

    Directory of Open Access Journals (Sweden)

    Fei Wang

    2017-11-01

    Full Text Available The optimal dispatching model for a stand-alone microgrid (MG is of great importance to its operation reliability and economy. This paper aims at addressing the difficulties in improving the operational economy and maintaining the power balance under uncertain load demand and renewable generation, which could be even worse in such abnormal conditions as storms or abnormally low or high temperatures. A new two-time scale multi-objective optimization model, including day-ahead cursory scheduling and real-time scheduling for finer adjustments, is proposed to optimize the operational cost, load shedding compensation and environmental benefit of stand-alone MG through controllable load (CL and multi-distributed generations (DGs. The main novelty of the proposed model is that the synergetic response of CL and energy storage system (ESS in real-time scheduling offset the operation uncertainty quickly. And the improved dispatch strategy for combined cooling-heating-power (CCHP enhanced the system economy while the comfort is guaranteed. An improved algorithm, Search Improvement Process-Chaotic Optimization-Particle Swarm Optimization-Elite Retention Strategy (SIP-CO-PSO-ERS algorithm with strong searching capability and fast convergence speed, was presented to deal with the problem brought by the increased errors between actual renewable generation and load and prior predictions. Four typical scenarios are designed according to the combinations of day types (work day or weekend and weather categories (sunny or rainy to verify the performance of the presented dispatch strategy. The simulation results show that the proposed two-time scale model and SIP-CO-PSO-ERS algorithm exhibit better performance in adaptability, convergence speed and search ability than conventional methods for the stand-alone MG’s operation.

  15. Why Don’t They Participate? A Self-Study of Chinese Graduate Students’ Classroom:Involvement in North America

    Directory of Open Access Journals (Sweden)

    Chunlei Lu

    2010-07-01

    Full Text Available China is now the world’s largest source of international students. In terms of learning performance, Chinese graduate students studying in North America exhibit distinct differences from students who are born and raised in North America. Conflicting cultural values compel Chinese students to reconcile East-West cultures, and put an onus on North American instructors to implement culturally-sensitive pedagogy. Employing the theoretic framework of yin-yang theory, this paper examines Chinese graduate students’ classroom performance against the backdrop of East-West cultural negotiation, and specifically seeks to identify which factors inhibit Chinese graduate students’ participation in North American classrooms. Drawing from their own living experiences, the authors employ self-study in the methodological form of narrative inquiry – in conjunction with references from existing literature – to investigate Chinese graduates’ classroom challenges. Results reveal six factors impacting students’ classroom performance: language; knowledge of the education system; knowledge of the social system; personality; influence of traditional culture; and social/economic/political changes. Future research directions are also suggested.Key words: Chinese graduates, East-West, cross-culture, North America, classroom involvement, self-study 

  16. The international phase 4 validation study of the EORTC QLQ-SWB32: a stand-alone measure of spiritual wellbeing (SWB) for people receiving palliative care for cancer

    OpenAIRE

    Vivat, B.; Young, T.; Winstanley, J.; Arraras, J.; Black, K.; Boyle, F.; Brédart, A.; Costantini, A.; Guo, J.; Irarrazaval, M. E.; Kobayashi, K.; Kruizinga, R.; Navarro, M.; Omidvari, S.; Rohde, G. E.

    2017-01-01

    The EORTC Quality of Life (QL) Group has just completed the final phase (field-testing and validation) of an international project to develop a stand-alone measure of spiritual wellbeing (SWB) for palliative cancer patients. Participants (n= 451) - from 14 countries on four continents; 54% female; 188 Christian, 50 Muslim, 156 with no religion - completed a provisional 36-item measure of SWB plus the EORTC QLQ-C15-PAL (PAL), then took part in a structured debriefing interview. All items showe...

  17. Wireless network of stand-alone end effect probes for soil in situ permittivity measurements over the 100MHZ-6GHz frequency range

    Science.gov (United States)

    Demontoux, François; Bircher, Simone; Ruffié, Gilles; Bonnaudiin, Fabrice; Wigneron, Jean-Pierre; Kerr, Yann

    2017-04-01

    , it should be useful to install many probes on the same site to obtain permittivity measurements over a large area. To reach this goal, the probes should communicate with each other to send data to a record device. Furthermore, it is needed to record measurements over a long time period (many months) to study the in-situ dielectric soil property variations according to changing weather conditions and seasonal trends. The goal of the research work presented is to develop a dielectric sensor system based on end effect probes able to communicate the data using wireless technology. It must be stand-alone from an electric and data recording point of view so it must integrate a VNA circuit instead of the ANRITSU VNA used for the moment. The LoRa wireless technology has been selected because of its low electric consumption and the large distance between equipment available. LoRaWAN™ is a Low Power Wide Area Network specification intended for wireless battery operated devices. The LoRaWAN data rates range from 0.3 kbps to 50 kbps which is sufficient for our probes' data exchanges. We will present the work done to perform the VNA and the LoRa communication board as well as the work done to improve the probes and the permittivity computation algorithm.

  18. IEA PVPS Task 3. Use of photovoltaic systems in stand-alone and island applications. 'Swiss participation'; IEA PVPS Task 3. Use of photovoltaic systems in stand-alone and island applications. 'Participation Suisse'

    Energy Technology Data Exchange (ETDEWEB)

    Villoz, M. [Dynatex SA, Morges (Switzerland)

    2004-07-01

    This report describes the work done during five years of the second phase of Task 3 of the photovoltaic power systems programme of the International Energy Agency (IEA-PVPS). Task 3 activities were concentrated on stand-alone photovoltaic systems with the main effort on improving the quality and reducing the cost of these systems. The work was divided in 2 sub-tasks whose first one was concentrated on quality insurance schemes and second one on technical recommendations coming from practical experience. Twelve original reports have been published covering topics that can be sorted in 4 categories: the first one is dedicated on quality issues with a review of existing standards in the participating countries and a double paper giving quality assurance recommendations on project management and examples of applying these rules in practical cases. The second category dwelled on photovoltaic systems with papers on charge controllers, on lightning protection and monitoring of systems. The third category presents interesting studies on the storage of energy which remains the main subject where improvements should be made in order to lower the cost of energy; four papers describe the management and the test procedures of lead-acid batteries, how to choose a lead-acid battery and finally are there alternatives to lead-acid batteries for the storage of photovoltaic electricity. The last category worked on loads and users of renewable energy and gives a large amount of experience with loads, how to choose them and how the energy can be better used through demand side management. (author)

  19. Feasibility Analysis and Simulation of a Stand-Alone Photovoltaic Energy System for Electricity Generation and Environmental Sustainability – Equivalent to 650VA Fuel-Powered Generator – Popularly Known as “I Pass My Neighbour”

    International Nuclear Information System (INIS)

    Ani, Vincent Anayochukwu

    2015-01-01

    Photovoltaic (PV) power system can be used to replace wholly 650VA generator for electricity generation for household use in Nigeria. This paper presented the feasibility analysis of load data and simulation study of a stand-alone PV power system that produced the electrical needs of a household. This study is based on designing of PV energy system for household use. The patterns of load consumption within the household were studied and suitably modeled for simulation. The simulation study indicates that energy requirements to provide electricity, which is equivalent to 650VA generator for household use in Nigeria, can be accomplished by 520 W solar PV array, 2312 Ah nominal capacity battery, and a 1 kW DC/AC inverter. This would be suitable for deployment of 100% clean energy for environmental sustainability and uninterruptable power performance in the household. The results of this research show that, with a low-power consuming appliances, it is possible to meet the entire annual electricity demand of a single household solely through a stand-alone PV energy supply. Installing solar panels by most Nigerian home can significantly reduce home reliance on government power thereby reduce the strain on the current capacity of our power generation infrastructure. A detailed design and description of the system were presented in this paper.

  20. Feasibility Analysis and Simulation of a Stand-Alone Photovoltaic Energy System for Electricity Generation and Environmental Sustainability – Equivalent to 650VA Fuel-Powered Generator – Popularly Known as “I Pass My Neighbour”

    Energy Technology Data Exchange (ETDEWEB)

    Ani, Vincent Anayochukwu, E-mail: vincent_ani@yahoo.com [Department of Electronic Engineering, University of Nigeria Nsukka, Nsukka (Nigeria)

    2015-09-11

    Photovoltaic (PV) power system can be used to replace wholly 650VA generator for electricity generation for household use in Nigeria. This paper presented the feasibility analysis of load data and simulation study of a stand-alone PV power system that produced the electrical needs of a household. This study is based on designing of PV energy system for household use. The patterns of load consumption within the household were studied and suitably modeled for simulation. The simulation study indicates that energy requirements to provide electricity, which is equivalent to 650VA generator for household use in Nigeria, can be accomplished by 520 W solar PV array, 2312 Ah nominal capacity battery, and a 1 kW DC/AC inverter. This would be suitable for deployment of 100% clean energy for environmental sustainability and uninterruptable power performance in the household. The results of this research show that, with a low-power consuming appliances, it is possible to meet the entire annual electricity demand of a single household solely through a stand-alone PV energy supply. Installing solar panels by most Nigerian home can significantly reduce home reliance on government power thereby reduce the strain on the current capacity of our power generation infrastructure. A detailed design and description of the system were presented in this paper.

  1. Teaching ecosystem and environment and its effect on the environmental consciousness of grade 9 students: A preliminary self study

    Science.gov (United States)

    Pantongkam, Monta; Wongboonnak, Sompratana; Khumwong, Pinit

    2018-01-01

    This research is a self-study research. The aims of the research were to reflect a teaching and learning process in a classroom on the topic of ecosystem and environment; a part of basic science subjects, and investigate the effect of a teaching on environmental consciousness. As a self-study research, the first author was a practitioner who taught grade ninth students classroom consisting of 50 students of an extra-large high school in Bangkok during the second semester of 2016 academic year. Data of the teaching method was collected by using teaching logs and critical friend interviews. The data was qualitatively analyzed by using content analysis. The effectiveness of teaching the environmental consciousness was investigated by using a 5 level-rating scale the environmental consciousness questionnaire. The questionnaire was administered three times, at the beginning of the semester, before and after learning the topic ecosystem and environment. The data was statistically analyzed by mean, standard deviation, and analysis of variance (one -way ANOVA). The results were indicated that: 1. The teacher directed all classroom activities, used power point to show the contents and pictures while she was talking and students were listening. The teacher often asked questions and mostly assigned students to work alone and sometimes in a group. Students only studied in the classroom. After learning, the students were assigned to do work sheets alone such as searching for information and making reports. 2. The grade 9 students had no significantly different level of the environmental consciousness comparing between the beginning of the semester (x ¯ = 3.33), before learning (x ¯ = 3.35) and after learning (x ¯ = 3.40). It can be concluded that this teaching and learning process cannot promote the environmental consciousness. This study was a preliminary study, the results indicate the need for change of teaching practice in the classroom.

  2. Is the radiographic subsidence of stand-alone cages associated with adverse clinical outcomes after cervical spine fusion? An observational cohort study with 2-year follow-up outcome scoring.

    Science.gov (United States)

    Zajonz, Dirk; Franke, Anne-Catherine; von der Höh, Nicolas; Voelker, Anna; Moche, Michael; Gulow, Jens; Heyde, Christoph-Eckhard

    2014-01-01

    The stand-alone treatment of degenerative cervical spine pathologies is a proven method in clinical practice. However, its impact on subsidence, the resulting changes to the profile of the cervical spine and the possible influence of clinical results compared to treatment with additive plate osteosynthesis remain under discussion until present. This study was designed as a retrospective observational cohort study to test the hypothesis that radiographic subsidence of cervical cages is not associated with adverse clinical outcomes. 33 cervical segments were treated surgically by ACDF with stand-alone cage in 17 patients (11 female, 6 male), mean age 56 years (33-82 years), and re-examined after eight and twenty-six months (mean) by means of radiology and score assessment (Medical Outcomes Study Short Form (MOS-SF 36), Oswestry Neck Disability Index (ONDI), painDETECT questionnaire and the visual analogue scale (VAS)). Subsidence was observed in 50.5% of segments (18/33) and 70.6% of patients (12/17). 36.3% of cases of subsidence (12/33) were observed after eight months during mean time of follow-up 1. After 26 months during mean time of follow-up 2, full radiographic fusion was seen in 100%. MOS-SF 36, ONDI and VAS did not show any significant difference between cases with and without subsidence in the two-sample t-test. Only in one type of scoring (painDETECT questionnaire) did a statistically significant difference in t-Test emerge between the two groups (p = 0.03; α = 0.05). However, preoperative painDETECT score differ significantly between patients with subsidence (13.3 falling to 12.6) and patients without subsidence (7.8 dropped to 6.3). The radiological findings indicated 100% healing after stand-alone treatment with ACDF. Subsidence occurred in 50% of the segments treated. No impact on the clinical results was detected in the medium-term study period.

  3. 农村污水处理太阳能光伏独立供电系统研究及工程示范%Research and Engineering Demonstration of Solar Energy Standalone Power Generation System on Rural Sewage Treatment

    Institute of Scientific and Technical Information of China (English)

    王守中; 张统; 张琪

    2017-01-01

    分析了农村污水处理太阳能独立供电的可行性和常见的光伏供电模式,并结合示范工程的设计及运行,探讨了农村污水处理太阳能光伏供电的设计参数和运行管护经验.%In this paper,the feasibility of solar energy independent power supply in rural sewage treatment,as well as the common pattern of the photovoltaic power generation were analyzed.Through the demonstration projects,the design parameters and the management experience of the solar energy standalone power generation system were systematically analyzed and summarized.

  4. New Learning Method of a Lecture of ‘Machine Fabrication’ by Self-study with Investigation and Presentation Incorporated

    Science.gov (United States)

    Kasuga, Yukio

    A new teaching method was developed in learning ‘machine fabrication’ for the undergraduate students. This consists of a few times of lectures, grouping, decision of industrial products which each group wants to investigate, investigation work by library books and internet, arrangement of data containing characteristics of the products, employed materials and processing methods, presentation, discussions and revision followed by another presentation. This new method is derived from one of the Finland‧s way of primary school education. Their way of education is believed to have boosted up to the top ranking in PISA tests by OECD. After starting the new way of learning, students have fresh impressions on this lesson, especially for self-study, the way of investigation, collaborate work and presentation. Also, after four years of implementation, some improvements have been made including less use of internet, and determination of products and fabricating methods in advance which should be investigated. By this, students‧ lecture assessment shows further encouraging results.

  5. Walking the Roads as Immigrant Mothers and Teacher Educators: A Collaborative Self-Study of Three Korean Immigrant Early Childhood Educators

    Science.gov (United States)

    Kim, Jinhee; Wee, Su-Jeong; Kim, Kyoung Jin

    2018-01-01

    Offering an analysis of our multifaceted experiences as three Korean immigrant early childhood teacher educators in the United States, this critical collaborative self-study examines how positions as immigrant mothers and teacher educators interplay with each other. This study also explores ways in which the intersectional experiences influence…

  6. Personally Driven Professional Development: Reflective Self-Study as a Way for Teachers to Take Control of Their Own Professional Development

    Science.gov (United States)

    Attard, Karl

    2017-01-01

    This article is about personally driven professional development through the use of reflective self-study. The argument that teachers need to take responsibility for their own learning while also taking decisions on how and in what areas to develop is strongly made throughout the article. Data for this article were gathered over a 10-year period…

  7. Optimal shifting of Photovoltaic and load fluctuations from fuel cell and electrolyzer to lead acid battery in a Photovoltaic/hydrogen standalone power system for improved performance and life time

    Science.gov (United States)

    Tesfahunegn, S. G.; Ulleberg, Ø.; Vie, P. J. S.; Undeland, T. M.

    Cost reduction is very critical in the pursuit of realizing more competitive clean and sustainable energy systems. In line with this goal a control method that enables minimization of the cost associated with performance and life time degradation of fuel cell and electrolyzer, and cost of battery replacement in PV/hydrogen standalone power systems is developed. The method uses the advantage of existing peak shaving battery to suppress short-term PV and load fluctuations while reducing impact on the cycle life of the battery itself. This is realized by diverting short-term cyclic charge/discharge events induced by PV/load power fluctuations to the upper band of the battery state of charge regime while operating the fuel cell and electrolyzer systems along stable (smooth) power curves. Comparative studies of the developed method with two other reference cases demonstrate that the proposed method fares better with respect to defined performance indices as fluctuation suppression rate and mean state of charge. Modeling of power electronics and design of controllers used in the study are also briefly discussed in Appendix A.

  8. Multi-site evaluation of a computer aided detection (CAD) algorithm for small acute intra-cranial hemorrhage and development of a stand-alone CAD system ready for deployment in a clinical environment

    Science.gov (United States)

    Deshpande, Ruchi R.; Fernandez, James; Lee, Joon K.; Chan, Tao; Liu, Brent J.; Huang, H. K.

    2010-03-01

    Timely detection of Acute Intra-cranial Hemorrhage (AIH) in an emergency environment is essential for the triage of patients suffering from Traumatic Brain Injury. Moreover, the small size of lesions and lack of experience on the reader's part could lead to difficulties in the detection of AIH. A CT based CAD algorithm for the detection of AIH has been developed in order to improve upon the current standard of identification and treatment of AIH. A retrospective analysis of the algorithm has already been carried out with 135 AIH CT studies with 135 matched normal head CT studies from the Los Angeles County General Hospital/ University of Southern California Hospital System (LAC/USC). In the next step, AIH studies have been collected from Walter Reed Army Medical Center, and are currently being processed using the AIH CAD system as part of implementing a multi-site assessment and evaluation of the performance of the algorithm. The sensitivity and specificity numbers from the Walter Reed study will be compared with the numbers from the LAC/USC study to determine if there are differences in the presentation and detection due to the difference in the nature of trauma between the two sites. Simultaneously, a stand-alone system with a user friendly GUI has been developed to facilitate implementation in a clinical setting.

  9. The international phase 4 validation study of the EORTC QLQ-SWB32: A stand-alone measure of spiritual well-being for people receiving palliative care for cancer.

    Science.gov (United States)

    Vivat, B; Young, T E; Winstanley, J; Arraras, J I; Black, K; Boyle, F; Bredart, A; Costantini, A; Guo, J; Irarrazaval, M E; Kobayashi, K; Kruizinga, R; Navarro, M; Omidvari, S; Rohde, G E; Serpentini, S; Spry, N; Van Laarhoven, H W M; Yang, G M

    2017-11-01

    The EORTC Quality of Life Group has just completed the final phase (field-testing and validation) of an international project to develop a stand-alone measure of spiritual well-being (SWB) for palliative cancer patients. Participants (n = 451)-from 14 countries on four continents; 54% female; 188 Christian; 50 Muslim; 156 with no religion-completed a provisional 36-item measure of SWB plus the EORTC QLQ-C15-PAL (PAL), then took part in a structured debriefing interview. All items showed good score distribution across response categories. We assessed scale structure using principal component analysis and Rasch analysis, and explored construct validity, and convergent/divergent validity with the PAL. Twenty-two items in four scoring scales (Relationship with Self, Relationships with Others, Relationship with Someone or Something Greater, and Existential) explained 53% of the variance. The measure also includes a global SWB item and nine other items. Scores on the PAL global quality-of-life item and Emotional Functioning scale weakly-moderately correlated with scores on the global SWB item and two of the four SWB scales. This new validated 32-item SWB measure addresses a distinct aspect of quality-of-life, and is now available for use in research and clinical practice, with a role as both a measurement and an intervention tool. © 2017 John Wiley & Sons Ltd.

  10. Performance parameters of a standalone PV plant

    International Nuclear Information System (INIS)

    El Fathi, Amine; Nkhaili, Lahcen; Bennouna, Amin; Outzourhit, Abdelkader

    2014-01-01

    Highlights: • We described in details a photovoltaic power plant installed in the remote rural village Elkaria (Essaouira Morocco – 7.2 kWp). • We presented the results of monitoring and some performance parameters of the plant such as load curve. • We discussed the energy management of the plant which is based on the droop mode control. • We presented and discussed the yields and the performance ratio of the plant. - Abstract: In this work we present a detailed description of a 7.2 kWp photovoltaic power plant installed in the remote rural village Elkaria (province of Essaouira in Morocco). This plant supplies 16 households with electricity through a local grid that was installed for this purpose. The results of monitoring some performance parameters of the plant such as load curve, the yields and the performance ratio are presented and discussed. The performance ratio of the PV plant varied between 33% and 70.2%. The low values of this parameter are mainly attributed to the way the battery inverter manages the energy flow

  11. Chapter 2: Stand-alone Applications - TOPCAT

    Science.gov (United States)

    Miller, C. J.

    Tool for OPerations on Catalogues And Tables or TOPCAT is a graphical viewer for table data. It offers a variety of ways to work with data tables, including a browser for the cell data, viewers for information about table and column metadata, dataset visualization, and even analysis. We discuss a small subset of TOPCAT's functionalities in this chapter. TOPCAT was originally developed as part of the Starlink program in the United Kingdom. It is now maintained by AstroGrid. The program is written in pure Java and available under the GNU General Public License. It is available for download and a version is included in the software distribution accompanying this book. TOPCAT is a GUI interface on top of the STIL library. A command line interface to this library, STILTS, described in Chapter 21 provides scriptable access to many of the capabilities described here. The purpose of this tutorial is to provide an overview of TOPCAT to the novice user. The best place to look for and learn about TOPCAT is the web page maintained by Mark B. Taylor. There, TOPCAT documentation is provided in HTML, PDF, via screen shots, etc. In this chapter we take the user through a few examples that give the general idea of how TOPCAT works. The majority of the functionality of TOPCAT is not included in this short tutorial. Our goal in this tutorial is to lead the reader through an exercise that would result in a publication quality figure (e.g. for a journal article). Specifically, we will use TOPCAT to show how the color-magnitude relation of a galaxy cluster compares to that of all galaxies in the Sloan Digital Sky Survey (York et al. 2000). This diagnostic is used not only in cluster finding, but its linear fit can provide insight into the age and/or metallicity of the oldest galaxies in galaxy clusters (which are some of the oldest galaxies in the Universe). The data we need for this exercise are: 1) the entire spectroscopic galaxy catalog from the SDSS, with galaxy positions, galaxy redshifts, and galaxy magnitudes and 2) galaxy members of a known galaxy cluster. For the former, we will download data directly from the SDSS servers to our local machine for analysis. For the latter, we will use TOPCAT's ability to call live cone search services.

  12. Utilizing the National Research Council's (NRC) Conceptual Framework for the Next Generation Science Standards (NGSS): A Self-Study in My Science, Engineering, and Mathematics Classroom

    Science.gov (United States)

    Corvo, Arthur Francis

    Given the reality that active and competitive participation in the 21 st century requires American students to deepen their scientific and mathematical knowledge base, the National Research Council (NRC) proposed a new conceptual framework for K--12 science education. The framework consists of an integration of what the NRC report refers to as the three dimensions: scientific and engineering practices, crosscutting concepts, and core ideas in four disciplinary areas (physical, life and earth/spaces sciences, and engineering/technology). The Next Generation Science Standards (NGSS ), which are derived from this new framework, were released in April 2013 and have implications on teacher learning and development in Science, Technology, Engineering, and Mathematics (STEM). Given the NGSS's recent introduction, there is little research on how teachers can prepare for its release. To meet this research need, I implemented a self-study aimed at examining my teaching practices and classroom outcomes through the lens of the NRC's conceptual framework and the NGSS. The self-study employed design-based research (DBR) methods to investigate what happened in my secondary classroom when I designed, enacted, and reflected on units of study for my science, engineering, and mathematics classes. I utilized various best practices including Learning for Use (LfU) and Understanding by Design (UbD) models for instructional design, talk moves as a tool for promoting discourse, and modeling instruction for these designed units of study. The DBR strategy was chosen to promote reflective cycles, which are consistent with and in support of the self-study framework. A multiple case, mixed-methods approach was used for data collection and analysis. The findings in the study are reported by study phase in terms of unit planning, unit enactment, and unit reflection. The findings have implications for science teaching, teacher professional development, and teacher education.

  13. English grammar in use a self-study reference and practice book for intermediate learners of English : with answers and CD-ROM

    CERN Document Server

    Murphy, Raymond

    2012-01-01

    English Grammar in Use Fourth edition is an updated version of the world's best-selling grammar title. It has a fresh, appealing new design and clear layout, with revised and updated examples, but retains all the key features of clarity and accessibility that have made the book popular with millions of learners and teachers around the world. The CD-ROM contains lots of additional practice exercises to consolidate learning, ideal for self-study but also suitable for reinforcement work in the classroom. An online version and book without answers are available separately.

  14. Free Trade and Tariffs: Level III, Unit 2, Lesson 1; Capitalism, Communism, Socialism: Lesson 2; Nationalism vs. Internationalism: Lesson 3. Advanced General Education Program. A High School Self-Study Program.

    Science.gov (United States)

    Manpower Administration (DOL), Washington, DC. Job Corps.

    This self-study program for high-school level contains lessons on: Free Trade and Tariffs; Capitalism, Communism, Socialism; and Nationalism vs. Internationalism. Each of the lessons concludes with a Mastery Test to be completed by the student. (DB)

  15. Post-processing in cardiovascular computed tomography. Performance of a client server solution versus a stand-alone solution; Bildnachverarbeitung in der kardiovaskulaeren Computertomografie. Performance von Client-Server- versus Einzelplatzloesung

    Energy Technology Data Exchange (ETDEWEB)

    Luecke, C.; Foldyna, B.; Andres, C.; Grothoff, M.; Nitzsche, S.; Gutberlet, M.; Lehmkuhl, L. [Leipzig Univ. - Herzzentrum (Germany). Abt. fuer Diagnostische und Interventionelle Radiologie; Boehmer-Lasthaus, S. [Siemens Healthcare Sector, Erlangen (Germany). Imaging and Therapy Div.

    2014-12-15

    Purpose: To compare the performance of server-based (CSS) versus stand-alone post-processing software (ES) for the evaluation of cardiovascular CT examinations (cvCT) and to determine the crucial steps. Data of 40 patients (20 patients for coronary artery evaluation and 20 patients prior to transcatheter aortic valve implantation [TAVI]) were evaluated by 5 radiologists with CSS and ES. Data acquisition was performed using a dual-source 128-row CT unit (SOMATOM Definition Flash, Siemens, Erlangen, Germany) and a 64-row CT unit (Brilliance 64, Philips, Hamburg, Germany). The following workflow was evaluated: Data loading, aorta and coronary segmentation, curved multiplanar reconstruction (cMPR) and 3 D volume rendering technique (3D-VRT), measuring of coronary artery stenosis and planimetry of the aortic annulus. The time requirement and subjective quality for the workflow were evaluated. The coronary arteries as well as the TAVI data could be evaluated significantly faster with CSS (5.5 ± 2.9 min and 8.2 ± 4.0 min, respectively) than with ES (13.9 ± 5.2 min and 15.2 ± 10.9 min, respectively, p = 0.01). Segmentation of the aorta (CSS: 1.9 ± 2.0 min, ES: 3.7 ± 3.3 min), generating cMPR of coronaries (CSS: 0.5 ± 0.2 min, ES: 5.1 ± 2.6 min), aorta and iliac vessels (CSS: 0.5 ± 0.4 min and 0.4 ± 0.4 min, respectively, ES: 1.6 ± 0.7 min and 2.8 ± 3 min, respectively) could be performed significantly faster with CSS than with ES with higher quality of cMPR, measuring of coronary stenosis and 3D-VRT (p < 0.05). Evaluation of cvCT can be accomplished significantly faster and better with CSS than with ES. The segmentation remains the most time-consuming workflow step, so optimization of segmentation algorithms could improve performance even further.

  16. [Application of a stand-alone interbody fusion cage based on a novel porous TiO2/glass composite. I. Implantation in the sheep cervical spine and radiological evaluation].

    Science.gov (United States)

    Korinth, M C; Hero, T; Mahnken, A H; Ragoss, C; Scherer, K

    2004-12-01

    Animals are becoming more and more common as in vitro and in vivo models for the human spine. Especially the sheep cervical spine is stated to be of good comparability and usefulness in the evaluation of in vivo radiological, biomechanical and histological behaviour of new bone replacement materials, implants and cages for cervical spine interbody fusion. In preceding biomechanical in vitro examination human cervical spine specimens were tested after fusion with either a cubical stand-alone interbody fusion cage manufactured from a new porous TiO/glass composite (Ecopore) or polymethyl-methacrylate (PMMA) after discectomy. First experience with the use of the new material and its influence on the primary stability after in vitro application were gained. After fusion of 10 sheep cervical spines in the levels C2/3 and C4/5 in each case with PMMA and with an Ecopore-cage, radiologic as well as computertomographic examinations were performed postoperatively and every 4 weeks during the following 2 and 4 months, respectively. Apart from establishing our animal model, we analysed the radiological changes and the degree of bony fusion of the operated segments during the course. In addition we performed measurements of the corresponding disc space heights (DSH) and intervertebral angles (IVA) for comparison among each other, during the course and with the initial values. Immediately after placement of both implants in the disc spaces the mean DSH and IVA increased (34.8% and 53.9%, respectively). During the following months DSH decreased to a greater extent in the Ecopore-segments than in the PMMA-segments, even to a value below the initial value (p>0.05). Similarly, the IVA decreased in both groups in the postoperative time lapse, but more distinct in the Ecopore-segments (pmodel of the sheep cervical spine. Distinct radiological changes regarding evident subsidence and detectable fusion of the segments, operated on with the new biomaterial, were seen. We demonstrated the

  17. Advanced grammar in use a self-study reference and practice book for advanced students of English : with answers and CD-ROM

    CERN Document Server

    Hewings, Martin

    2013-01-01

    An updated version of the highly successful Advanced Grammar in Use. This third edition, with answers and CD-ROM, is ideal for self-study. The book contains 100 units of grammar reference and practice materials, with illustrations in full colour and a user-friendly layout. It is ideal for learners preparing for the Cambridge Advanced, Proficiency or IELTS examinations, and is informed by the Cambridge International Corpus, which ensures the language is authentic and up-to-date. The CD-ROM includes 200 interactive exercises to reinforce the language learned in the book, plus customised tests and audio recordings to accompany the main exercises. Versions without answers and without the CD-ROM are available to purchase separately.

  18. Simulator program as a form of implementation of electronic teaching tools for self-study of foreign students at the stage of pre-university training

    Directory of Open Access Journals (Sweden)

    Andriy O. Savel'ev

    2015-06-01

    Full Text Available Questions of empowerment the organization of classroom and extracurricular self-study of foreign students at the stage of pre-university training through the implementation of electronic teaching tools as a component of computer training facilities in educational process are considered. Classification of modern electronic teaching tools as a component of computer hardware training, developed on the basis of modern information and communication technologies is offered. Version of program-simulator "Introductory course" is offered. The program is created by means of WEB-programming and uses training material of introductory course. Introductory course is one of the most important elements of teaching of scientific style of speech within the language training for the foreign students at the preparatory faculty.

  19. A comparison of anterior cervical discectomy and fusion (ACDF) using self-locking stand-alone polyetheretherketone (PEEK) cage with ACDF using cage and plate in the treatment of three-level cervical degenerative spondylopathy: a retrospective study with 2-year follow-up.

    Science.gov (United States)

    Chen, Yuqiao; Lü, Guohua; Wang, Bing; Li, Lei; Kuang, Lei

    2016-07-01

    To evaluate the clinical efficacy and radiological outcomes of anterior cervical discectomy and fusion (ACDF) using self-locking polyetheretherketone (PEEK) cages for treatment of three-level cervical degenerative spondylopathy. Twenty-eight patients underwent three-level ACDF using self-locking stand-alone PEEK cages (group A), and 26 patients underwent three-level ACDF using cages and plate fixation (group B) were reviewed retrospectively. Clinical efficacy was evaluated by pre- and post-operative Japanese Orthopedic Association (JOA) scores and Neck Disability Index (NDI). The operation time, blood loss, surgical results according to Odom's criteria and post-operative dysphagia status were also recorded. Radiological outcomes including fusion, cervical Cobb's lordosis, fused segment angle, disc height, and cage subsidence were assessed. Clinical outcome measures such as dysphagia and fusion rate and the results of surgery evaluated according to Odom's criteria were not statistically significant (P > 0.05) between groups. The operation time was shorter and blood loss was less in group A (P  0.05). Post-operative cage subsidence, the loss of disc height, cervical lordosis and the fused segment angle were relatively higher in group A than group B (P < 0.05). ACDF using self-locking stand-alone cages showed similar clinical results as compared to ACDF using cages and plate fixation for the treatment of three-level cervical degenerative spondylopathy. However, potential long-term problems such as cage subsidence, loss of cervical lordosis and fused segment angle post-operatively were shown to be associated with patients who underwent ACDF using self-locking stand-alone cages.

  20. Fiscal 2000 regional new energy vision formulation - Financially aided project. Report on regional new energy vision formulation for Ueno village (Object of survey: Commercialization feasibility study for a stand-alone type wind power generation system at Ueno German Culture Village); 2000 nendo Uenoson chiiki shin energy vision sakutei hokokusho. Ueno Doitsu bunkamura dokuritsugata furyoku hatsuden system jigyoka feasibility study chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-02-01

    A survey is conducted about the profitability of installing a stand-alone type wind power system at Ueno village (Miyako Island), Okinawa Prefecture. The German Culture Village, which is an integrated resort house provided with accommodations (500 people), educational and cultural facilities, and sports facilities consumes 272 MWh/year in electric power. The results of the survey are summarized in six chapters, which are (1) the survey of the business under the project to be the object of feasibility study, (2) project to be the object of feasibility study, (3) outline of the Okinawa Electric Power Co., Inc., Miyakojima system and problems to ensue from its interconnection with wind turbines, (4) survey of stand-alone type wind turbine power generation systems, (5) technical/economic feasibility study, and (6) project management and future tasks. It is concluded that there will be profit in the presence of a subsidy that covers 65% or more of the total cost of constructing a system comprising three 600 KW wind turbines, three 400 kW class diesel generators, and storage batteries. (NEDO)

  1. Supervisory Management in the Water/Wastewater Field: Self Study Program. Revised Second Edition. Textbook and Student Manual. Lessons 1-7 and Appendix. Executive Programs of the Graduate School of Business Administration of Michigan State University.

    Science.gov (United States)

    Liebrenz, Marilyn L., Ed.

    This document is the student manual for a self-study course on managerial principles as they relate to the water or wastewater treatment field. Each of the seven lessons is concerned with a segment of the management process and corresponds to reading material in the accompanying text. An objective and subjective test portion is included in each…

  2. Alternative route of process modification for biofuel production by embedding the Fischer-Tropsch plant in existing stand-alone power plant (10 MW) based on biomass gasification - Part I: A conceptual modeling and simulation approach (a case study in Thailand)

    DEFF Research Database (Denmark)

    Hunpinyo, Piyapong; Cheali, Peam; Narataruksa, Phavanee

    2014-01-01

    a base case process model coupled with techno-economic evaluation for the FT synthesis. In particular, the FT process configurations are designed and assessed using current kinetic laboratory data by our research group for modeling specific reactions in PFR reactor. The calculation of equipment sizing......The utilization of syngas shows a highly potential to improve the economic potential of the stand-alone power unit-based gasification plants as well as enhancing the growing demand of transportation fuels. The thermochemical conversion of biomass via gasification to heat and power generations from...... incurred several major unit operations is performed for once-through mode (no recycles of unconverted syngas) with electricity co-production. This study provides a detailed base-case model for the synthesis with the capacities of 1, 2 and 3 MW of syngas technology sharing and the comparison between...

  3. An exploration of the relationship between teacher beliefs and practices: Lessons from a self-study of a fourth- and fifth-grade science teacher

    Science.gov (United States)

    Connell, Shelley Sha'ron

    2007-12-01

    This study was an investigation of the relationship between teacher beliefs and teaching practices. The relationship was explored to address reported inconsistencies among teacher beliefs, teaching practices and reform goals reported over the past 30 years. A self-study methodology was employed to collect data in a fourth-grade (n = 12) and a fifth-grade (n = 7) class at a private elementary school. Data were collected using a reflective journal and the Traditional Versus Inquiry-Based Classroom Behaviors instrument. Self-data were triangulated with critical judgment data from focus groups and interviews with students, parents, and a peer teacher observer. Data were collected and analyzed in four segments: (a) teacher beliefs, (b) teaching practices, (c) congruency between teacher beliefs and teaching practices, and (d) factors that influence congruency. Teacher beliefs were listed at the start of the school year and analyzed in narrative format. Teaching practices were recorded in the journal and analyzed through coding. The relationship between beliefs and practices was explored on two levels, following Haney & McArthur's (2002) modified theory of planned behavior. First, congruency between beliefs and practices was determined, yielding beliefs that were either central (congruent with practices) or peripheral (incongruent with practices) to the author's belief system. Second, congruency between central beliefs and two categories of teaching principles was determined, yielding three subdivisions: constructivist core (congruent with constructivist principles), emerging core (congruent with general principles) and conflict core (incongruent with constructivist principles) beliefs. Data analysis showed 16 central beliefs (those congruent with practice) in operation. The study finding was that teacher beliefs and practices were largely congruent for this one teacher. This contrasted most published reports. Coupling application of the TPB and modified TPB, congruence

  4. Journal of Agriculture, Forestry and the Social Sciences - Vol 6, No 1 ...

    African Journals Online (AJOL)

    ... Of Pig Manure On The Growth And Yield Of Phaseolus vulgaris (Green Beans) ... Of Rabbits Fed Diets Supplemented With Copper Sulphate · EMAIL FULL TEXT ... E Supplimentation On Fat Composition And Keeping Quality Of Broiler Meat ...

  5. Size-Prediction Analysis for Stand-Alone Photovoltaic System

    International Nuclear Information System (INIS)

    Erusiafe, N. E.; Chendo, M. A. C.

    2002-01-01

    The cost - effectiveness of photovoltaic (PV) generator depends, among others, on its ability to satisfy energy demand and the cost of achieving this. In this work a step - by - step procedure for predicting the size of the main components of a stand - alone PV system (array and storage) is presented. The results yield an expression which can he used lo determine the size of both components at optimum cost and desired reliability. The result from this work compare favourably with some earlier works in that, the system sizes shows some degree of agreement

  6. Dynamic Performance of the Standalone Wind Power Driven Heat Pump

    OpenAIRE

    H. Li; P.E. Campana; S. Berretta; Y. Tan; J. Yan

    2016-01-01

    Reducing energy consumption and increasing use of renewable energyin the building sector arecrucial to the mitigation of climate change. Wind power driven heat pumps have been considered as a sustainable measure to supply heat for detached houses, especially those that even don’t have access to the grid. This work is to investigate the dynamic performance of a heat pump system directly driven by a wind turbine. The heat demand of a detached single family house was simulated in details. Accord...

  7. Radon Monitoring in Army Stand-Alone Housing Units

    Science.gov (United States)

    1990-04-01

    damage lung tissue and lead I to increased risk of developing lang cancer . Your risk of developing lung cancer from exposure to radon depends upon the...of developing lung cancer than exposure to a significantly elevated level for a short time. In general, your risk increases as the level of radon and...000mm 0Mmm *000 OOO 0 0w 0 0 000 -0-0 *4 0 880 mama 0 0000000000 000 000Eca ( el cN) 00 9 ’ qqO .00 1(10 0 -U M w co SEE wSS SEES NSEwESO m v MM O v mm

  8. use of standalone photovoltaic system for office building

    African Journals Online (AJOL)

    HOD

    OF TELECOMMUNICATION ENGINEERING, FEDERAL UNIV. ... This paper presents the design of a cost effective energy system for National Centre for ... company. In GC system, when the amount of energy generated by a PV system exceeds the demand loads, .... used by the researchers and the management staff of.

  9. Standalone vertex finding in the ATLAS muon spectrometer

    Czech Academy of Sciences Publication Activity Database

    Aad, G.; Abajyan, T.; Abbott, B.; Böhm, Jan; Chudoba, Jiří; Hejbal, Jiří; Jakoubek, Tomáš; Kepka, Oldřich; Kupčo, Alexander; Kůs, Vlastimil; Lokajíček, Miloš; Lysák, Roman; Marčišovský, Michal; Mikeštíková, Marcela; Myška, Miroslav; Němeček, Stanislav; Dos Santos, D.R.; Růžička, P.; Šícho, Petr; Staroba, Pavel; Svatoš, Michal; Taševský, Marek; Tic, Tomáš; Vrba, Václav

    2014-01-01

    Roč. 9, Feb (2014), s. 1-22 ISSN 1748-0221 R&D Projects: GA MŠk(CZ) LG13009 Institutional support: RVO:68378271 Keywords : muon spectrometers * performance of high energy physics * detectors * ATLAS * CERN LHC Coll Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.399, year: 2014

  10. Modeling Small Scale Solar Powered ORC Unit for Standalone Application

    Directory of Open Access Journals (Sweden)

    Enrico Bocci

    2012-01-01

    Full Text Available When the electricity from the grid is not available, the generation of electricity in remote areas is an essential challenge to satisfy important needs. In many developing countries the power generation from Diesel engines is the applied technical solution. However the cost and supply of fuel make a strong dependency of the communities on the external support. Alternatives to fuel combustion can be found in photovoltaic generators, and, with suitable conditions, small wind turbines or microhydroplants. The aim of the paper is to simulate the power generation of a generating unit using the Rankine Cycle and using refrigerant R245fa as a working fluid. The generation unit has thermal solar panels as heat source and photovoltaic modules for the needs of the auxiliary items (pumps, electronics, etc.. The paper illustrates the modeling of the system using TRNSYS platform, highlighting standard and “ad hoc” developed components as well as the global system efficiency. In the future the results of the simulation will be compared with the data collected from the 3 kW prototype under construction in the Tuscia University in Italy.

  11. Benchmarking the Collocation Stand-Alone Library and Toolkit (CSALT)

    Science.gov (United States)

    Hughes, Steven; Knittel, Jeremy; Shoan, Wendy; Kim, Youngkwang; Conway, Claire; Conway, Darrel J.

    2017-01-01

    This paper describes the processes and results of Verification and Validation (VV) efforts for the Collocation Stand Alone Library and Toolkit (CSALT). We describe the test program and environments, the tools used for independent test data, and comparison results. The VV effort employs classical problems with known analytic solutions, solutions from other available software tools, and comparisons to benchmarking data available in the public literature. Presenting all test results are beyond the scope of a single paper. Here we present high-level test results for a broad range of problems, and detailed comparisons for selected problems.

  12. Standalone, battery powered radiation monitors for accelerator electronics

    CERN Document Server

    Wijnands, T; Spiezia, G

    2009-01-01

    A technical description of the design of a new type of radiation monitors is given. The key point in the design is the low power consumption inferior to 17 mW in radiation sensing mode and inferior to 0.3 mW in standby mode. The radiation monitors can operate without any external power or signal cabling and measure and store radiation data for a maximum period of 800 days. To read the radiation data, a standard PC can be connected via a USB interface to the device at any time. Only a few seconds are required to read out a single monitor. This makes it possible to survey a large network of monitoring devices in a short period of time, for example during a stop of the accelerator.

  13. standalone general purpose data logger design and implementation

    African Journals Online (AJOL)

    eobe

    volatile EEPROM data memory, four AT24C256 2-wire serial EEPROM chips were used for data storage. wire serial ... analog electrical signal that relays information about .... in-code, ADC, Serial Communication and short term memory ...

  14. Model for optimum design of standalone hybrid renewable energy ...

    African Journals Online (AJOL)

    An optimization model for the design of a hybrid renewable energy microgrid ... and increasing the rated power of the wind energy conversion system (WECS) or solar ... a 70% reduction in gas emissions and an 80% reduction in energy costs.

  15. PV-Battery Sizing for Stand-Alone Lighting Applications

    OpenAIRE

    Herteleer, Bert; Cappelle, Jan; Appels, Reinhart; Lefevre, Buvana; Driesen, Johan; Catthoor, Francky

    2013-01-01

    This paper presents a follow-up and addition to a system sizing spreadsheet, detailed in [An autonomous photovoltaic system sizing program for office applications in Africa], with a focus on sizing or verifying the employability of an off-grid PV-battery system for night lighting. A dimensionless criterion, the Battery Usable Fraction UF_batt is defined, which aids both the calculations of systems and allows an approximate comparison of batteries, regardless of the employed battery chemistry....

  16. Use of standalone photovoltaic system for office building: the case ...

    African Journals Online (AJOL)

    This paper presents the design of a cost effective energy system for National Centre for Hydropower Research and Development (NACHRED) building to supply its daily energy requirements. The daily hourly load demand of the building was measured with FLUKE 434 Series II Energy Analyzer. The measurement was ...

  17. Constraining lidar stand-alone retrievals with lunar photometry measurements

    Science.gov (United States)

    Ortiz-Amezcua, Pablo; Luis Guerrero-Rascado, Juan; Antonio Benavent-Oltra, Jose; Román, Roberto; Böckmann, Christine; Alados-Arboledas, Lucas

    2018-04-01

    This study combines atmospheric optical information measured with lidar and nocturnal photometers in order to find configurations that allow for the retrieval of particle microphysical properties without "3+2" lidar setups. It has been carried out using data measured at the EARLINET Granada station during the experimental campaign SLOPE in the framework of ACTRIS-2 project.

  18. A novel standalone track reconstruction algorithm for the LHCb upgrade

    CERN Multimedia

    Quagliani, Renato

    2018-01-01

    During the LHC Run III, starting in 2020, the instantaneous luminosity of LHCb will be increased up to 2×1033 cm−2 s−1, five times larger than in Run II. The LHCb detector will then have to be upgraded in 2019. In fact, a full software event reconstruction will be performed at the full bunch crossing rate by the trigger, in order to profit of the higher instantaneous luminosity provided by the accelerator. In addition, all the tracking devices will be replaced and, in particular, a scintillating fiber tracker (SciFi) will be installed after the magnet, allowing to cope with the higher occupancy. The new running conditions, and the tighter timing constraints in the software trigger, represent a big challenge for the track reconstruction. This talk presents the design and performance of a novel algorithm that has been developed to reconstruct track segments using solely hits from the SciFi. This algorithm is crucial for the reconstruction of tracks originating from long-lived particles such as KS and Λ. ...

  19. EXPERIMENTAL ANALYSIS OF THE CHARACTERISTIC PERFORMANCE OF STANDALONE PHOTOVOLTAIC SYSTEM

    OpenAIRE

    Birendra Kishore; Anirban Nandy*; O.P. Pandey

    2016-01-01

    This paper demonstrates an insight solar PV Stand Alone system which is a practical model with a halogen light source. At different situations the performance of solar PV cells are analyzed. The system produces power with depending on the change in halogen light intensity & temperature. A theoretical & experimental analysis of the PV cell can be achieved. In this paper the I-V & P-V characteristic of the solar photovoltaic cells with changes in temperature and isolation have been showed. With...

  20. Standalone vertex finding in the ATLAS muon spectrometer

    DEFF Research Database (Denmark)

    Aad, A.; Abajyan, T.; Abbott, B.

    2014-01-01

    A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The perf......A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths....... The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011....

  1. A self-study using action research

    DEFF Research Database (Denmark)

    Bao, Rui

    2015-01-01

    Classroom interaction has been seen as one of the primary means for L2 learning. One common argument is that during conversational interaction, learners receive feedback on their L2 input, thus noticing the difference between their L2 production and the target form. This ‘noticing’ drives learner...

  2. Hearing Conservation Self-Study #12350

    Energy Technology Data Exchange (ETDEWEB)

    Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-09

    Occupational hearing loss is one of the most common work-related illnesses in the United States (US). From 22 to 30 million US workers are exposed to hazardous noise levels at work, and 25% of these workers will develop permanent hearing loss. Hearing loss from noise is slow and painless, and you can have a disability before you notice it. This course presents the hazards associated with workplace noise, the purpose and elements of the Los Alamos National Laboratory (LANL) Hearing Conservation Program (HCP), and controls that are available to reduce your exposure to hazardous levels of noise.

  3. Thermal Stress Awareness, Self-Study #18649

    Energy Technology Data Exchange (ETDEWEB)

    Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-11-15

    Thermal stresses can expose individuals to a variety of health hazards at work, home, and play. Every year thermal stresses cause severe injuries and death to a large range of people, from elderly people in cities during summer heat waves to young people engaged in winter mountaineering. Awareness is the key to preventing the health hazards associated with thermal stresses. This course is designed for personnel at Los Alamos National Laboratory (LANL). It addresses both heat and cold stresses and discusses their factors, signs and symptoms, treatments, and controls.

  4. RCRA Refresher Self-Study, Course 28582

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, Lewis Edward [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-01-30

    Federal and state regulations require hazardous and mixed waste facility workers at treatment and storage facilities (TSFs) and <90-day accumulation areas to be trained in hazardous and mixed waste management. This course will refamiliarize and update <90-day accumulation area workers, TSF workers, and supervisors of TSF workers regarding waste identification, pollution prevention, storage area requirements, emergency response procedures, and record-keeping requirements.

  5. Development of student self-study activities

    DEFF Research Database (Denmark)

    Kvols, Anja Madsen; Kim, Won-Chung; Christensen, Dorthe Ansine

    2015-01-01

    of the teacher education and will aim at strengthening students' motivation for choosing self-initiated activities. The motivation should for example be based on students´ perception of relevance and quality of their own initiatives and the possibility of guidance in self-selected activities. This paper...... the possibility of developing educational theories for the teachers’ education in an effort to develop independence as a study skill. Keywords: studieaktivitetsmodellen, selvstændige studieaktiviteter, kortlægning af studieaktiviteter...

  6. Alternative route of process modification for biofuel production by embedding the Fischer–Tropsch plant in existing stand-alone power plant (10 MW) based on biomass gasification – Part I: A conceptual modeling and simulation approach (a case study in Thailand)

    International Nuclear Information System (INIS)

    Hunpinyo, Piyapong; Cheali, Peam; Narataruksa, Phavanee; Tungkamani, Sabaithip; Chollacoop, Nuwong

    2014-01-01

    Graphical abstract: SynBiofuel production through existing gasification plants in Thailand, using waste agricultural biomass as raw material, was studied. The process design was initiated conceptually in the areas of gas phase reaction system via Fischer-Tropsch (FT) synthesis. The development of FT configurations on syngas conversion to transportation fuels (e.g., diesel range) was investigated. In order to develop a techno-economic assessment, the three different capacities corresponding to 1 MW, 2 MW and 3 MW based on thermal input of syngas were evaluated. Once-through FT concept was proposed in which the unconverted syngas was combusted with air in an externally fired gas turbine (EFGT) to produce surplus electricity. The results of process simulation were discussed open-mindedly including the overall plant design and energy efficiency. Preliminary economics, and some site specific situations under which additional capital cost savings on existing infrastructure was realized. - Highlights: • Experimental results were used and integrated with a reactor model for SynBiofuel. • Process simulation with the lumped reaction rate was used to achieve accurate results. • Process simulation was performed using ASPEN Plus to design FT configurations. • Maximum energy FT efficiency was approximately 37%. • Economic potential was computed by ROI and PBP resulting in the attractive solutions. - Abstract: The utilization of syngas shows a highly potential to improve the economic potential of the stand-alone power unit-based gasification plants as well as enhancing the growing demand of transportation fuels. The thermochemical conversion of biomass via gasification to heat and power generations from the earlier study is further enhanced by integrating Fischer–Tropsch (FT) synthesis with the existing gasification pilot scale studied previously. To support the potential and perspectives in major economies due to scaling up in developing countries such as Thailand

  7. Plants and Photosynthesis: Level III, Unit 3, Lesson 1; The Human Digestive System: Lesson 2; Functions of the Blood: Lesson 3; Human Circulation and Respiration: Lesson 4; Reproduction of a Single Cell: Lesson 5; Reproduction by Male and Female Cells: Lesson 6; The Human Reproductive System: Lesson 7; Genetics and Heredity: Lesson 8; The Nervous System: Lesson 9; The Glandular System: Lesson 10. Advanced General Education Program. A High School Self-Study Program.

    Science.gov (United States)

    Manpower Administration (DOL), Washington, DC. Job Corps.

    This self-study program for the high-school level contains lessons in the following subjects: Plants and Photosynthesis; The Human Digestive System; Functions of the Blood; Human Circulation and Respiration; Reproduction of a Single Cell; Reproduction by Male and Female Cells; The Human Reproductive System; Genetics and Heredity; The Nervous…

  8. PAA, WSH, and CIS Overview Self-Study #47656

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Rachel Anne [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-14

    This course presents an overview of the Department of Energy’s (DOE’s) regulatory requirements relevant to the Price-Anderson Amendments Act (PAAA, also referred to as nuclear safety), worker safety and health (WSH), and classified information security (CIS) that are enforceable under the DOE enforcement program; describes the DOE enforcement process; and provides an overview of Los Alamos National Laboratory’s (LANL’s) internal compliance program relative to these DOE regulatory requirements. The LANL PAAA Program is responsible for maintaining LANL’s internal compliance program, which ensures the prompt identification, screening, and reporting of noncompliances to DOE regulatory requirements pertaining to nuclear safety, WSH, and CIS to build the strongest mitigation position for the Laboratory with respect to civil or other penalties.

  9. Georgia Compliance Review Self-Study FY 01.

    Science.gov (United States)

    Georgia State Dept. of Education, Atlanta.

    Intended for evaluation of local compliance with special education federal and state legal requirements, this compliance review document includes both the compliance requirements and the criteria by which compliance is determined during the onsite compliance review of Georgia local school systems and state-operated programs. Each legal requirement…

  10. Self-study manual for introduction to computational fluid dynamics

    OpenAIRE

    Nabatov, Andrey

    2017-01-01

    Computational Fluid Dynamics (CFD) is the branch of Fluid Mechanics and Computational Physics that plays a decent role in modern Mechanical Engineering Design process due to such advantages as relatively low cost of simulation comparing with conduction of real experiment, an opportunity to easily correct the design of a prototype prior to manufacturing of the final product and a wide range of application: mixing, acoustics, cooling and aerodynamics. This makes CFD particularly and Computation...

  11. Using a CAS Self-Study to Teach Assessment Practice

    Science.gov (United States)

    Bourke, Brian

    2017-01-01

    There are likely as many approaches to teaching assessment as there are people teaching assessment. Graduate courses on assessment can be structured with a singular focus, such as learning outcomes assessment, or along a competencies-based framework. Such frameworks include the Assessment Skills and Knowledge (ASK) Standards developed by College…

  12. Developing a Pedagogy of "Making" through Collaborative Self-Study

    Science.gov (United States)

    Bullock, Shawn M.; Sator, Andrea

    2018-01-01

    We believe that the ideas associated with the Maker Movement have profound implications for teacher education. We have isolated the pedagogical principles of hack, adapt, design, and create as central to exploring how they work with teacher candidate participants in a maker pedagogy lab. We frame these ideas as Maker Pedagogy, which is the…

  13. Seeing the Shadow of the Self: Studies on Workplace Deviance

    NARCIS (Netherlands)

    N.A. den Nieuwenboer (Niki)

    2008-01-01

    textabstractWhy do good people do bad things? The assumption that underlies the research presented in this dissertation is that only some of those who engage in organizational deviance are individuals of dubious morality, and that most of the organizational deviants are good people who are merely

  14. Analysis and optimization of hybrid excitation permanent magnet synchronous generator for stand-alone power system

    Science.gov (United States)

    Wang, Huijun; Qu, Zheng; Tang, Shaofei; Pang, Mingqi; Zhang, Mingju

    2017-08-01

    In this paper, electromagnetic design and permanent magnet shape optimization for permanent magnet synchronous generator with hybrid excitation are investigated. Based on generator structure and principle, design outline is presented for obtaining high efficiency and low voltage fluctuation. In order to realize rapid design, equivalent magnetic circuits for permanent magnet and iron poles are developed. At the same time, finite element analysis is employed. Furthermore, by means of design of experiment (DOE) method, permanent magnet is optimized to reduce voltage waveform distortion. Finally, the validity of proposed design methods is validated by the analytical and experimental results.

  15. environmental/climatic effect on stand-alone solar energy supply

    African Journals Online (AJOL)

    This paper investigates the climatic effects and environmental variations on the perfor- mance of a ... inter-connected arrays due to shades from clouds, tress and ... Modeling of Solar Module .... needs. The earth revolves around the sun in an.

  16. Standalone cool/freeze cluster driven by solar photovoltaic energy. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Katic, I.; Pedersen, Per Henrik; Jacobsen, Emil

    2010-12-15

    The objective of the project is to develop and demonstrate a grid-independent cold storage system for perishable food, medicine or other goods, with a special focus on the need for such systems in developing countries with a sparse and unreliable supply of electricity. The project is directly based on the result from the international SolarChill project where a unique battery less solar driven vaccine refrigerator was developed by Vestfrost in cooperation with Danish Technological Institute (DTI). The project partners are Danish Technological Institute (Project manager), Danfoss, Grundfos, Fresvik (Norway) and Karise Klejnsmedie. The refrigeration system is set up at the solar energy test area of DTI, where a PV array with a nominal power of 800 W has been established. The batteries and charge controller are purchased from a Danish PV system retailer. The inverter is a trapezoid 50 Hz 230 Vac inverter is a robust type with high surge current. The two AC cabinets are standard low energy household freezers, whereas the DC cabinet is a special ice-lined refrigerator (fresh food/middle temperature) with high thermal capacity in its walls. The selection of large chest type freezers gives low specific energy consumption due to a high volume/surface ratio and low air infiltration. The commercial low energy cabinets are relatively inexpensive, and can operate with an extremely low consumption if the thermostat is set to cooling mode. As part of this quite extensive project, there have been a number of contacts with associated activities as well as direct requests from companies operating in 3rd world countries. The two most important cases have been a milk-cooling project in Uganda and a World Bank GEF project regarding improved storage methods for vaccines. The current design of the PV driven refrigeration system could be modified to milk cooling, and this is actually being investigated by the Danish company Karise Klejnsmedie who are specialist in stainless steel processing. They are currently designing a prototype with a cooling capacity of 75 liters/day for test at DTI. The relief organization PATH is a specialist in cold chain vaccine storage and transport in developing countries. One of the major problems with vaccines is that they cannot tolerate freezing, but on the other hand they need cooling. Current use of icepacks in transport boxes requires precise adjustment of icepack temperature before outreach, but still there is a risk of freezing. A new type of icepack with a freezing temperature of 5-6 deg. C may solve this problem, but until now they are frozen in ordinary freezers to -18 deg. C in order to be sure they are totally frozen (avoiding sub cooling). If they could be frozen at, say, 1-2 deg. C they could be used immediately for vaccine transport without risk of freezing the vaccine. It seems that the PLC regulated chest freezer from the current project could be well suited for this purpose, and its size is perfect for the type of rack that is used by PATH to hold the icepacks. The rack with icepacks will be tried in the lab by DTI in the near future. (Author)

  17. RUP2004 - High definition apparatus for Standalone, network and micro-array applications in seismic

    Czech Academy of Sciences Publication Activity Database

    Štrunc, Jaroslav; Brož, Milan

    2006-01-01

    Roč. 6, č. 2 (2006), s. 281-283 ISSN 1213-1962 R&D Projects: GA ČR(CZ) GD205/05/H020 Institutional research plan: CEZ:AV0Z30460519 Keywords : seismology * GPS * GSM Subject RIV: DC - Siesmology, Volcanology, Earth Structure

  18. Letting Go of Stand-Alone Technology: How to Blend Technology into Literacy Stations

    Science.gov (United States)

    Calvert, Heather

    2015-01-01

    With the nationwide focus on increasing students understanding and use of technology, many teachers are beginning to incorporate a variety of technology into small group rotations. However, the use of technology during these rotations often does not require students to use higher level thinking or problem solving skills. By eliminating the…

  19. Optimal Sizing and Operation of Stand-Alone Hybrid Power Systems

    DEFF Research Database (Denmark)

    Kyriakidis, Ioannis; Chaudhary, Sanjay; Pillai, Jayakrishnan Radhakrishna

    2014-01-01

    for autonomous applications. Based on the island’s wind and solar potential, wind and solar systems appear as the most competitive solution while battery technologies provide the most feasible option for storing the excess energy. In the next, simulation models are developed in HOMER software. Various ratings...... of Renewable Energy Sources and Energy Storage Systems are considered and the most feasible combinations with respect to the Net Present Cost are calculated. The results have been assessed according to three scenarios, each of them representing a different policy and encountering several constraints....... Afterwards, steady-state analysis of the network is carried out considering typical cases of seasonal demand. The static model is developed in DIgSILENT PowerFactory software and the system’s behavior is investigated. In the following, the optimal placement for the wind, solar and storage units is discussed...

  20. Taking Educational Games Seriously: Using the RETAIN Model to Design Endogenous Fantasy into Standalone Educational Games

    Science.gov (United States)

    Gunter, Glenda A.; Kenny, Robert F.; Vick, Erik H.

    2008-01-01

    We are witnessing a mad rush to pour educational content into games in an ad hoc manner in hopes that player/learners are motivated simply because the content is housed inside a game. A failure to base educational game design on well-established learning and instructional theories increases the risk of the game failing to meet its intended…

  1. Assessing Self-Regulation of Learning Dimensions in a Stand-alone MOOC Platform

    Directory of Open Access Journals (Sweden)

    Daniel Friday Owoichoche Onah

    2017-06-01

    Full Text Available A capacity for self-regulated learning (SRL has long been recognised as an important factor in successful studies. Although educational researchers have started to investigate the concept of SRL in the context of online education, very little is yet known about SRL in relation to massive open online courses (MOOCs or of appropriate strategies to foster SRL skills in MOOC learners. Self-regulation is particularly important in a MOOC-based study, which demands effective independent learning, and where widely acknowledged high dropout rates are observed. This study reports an investigation and assessment of the concept of SRL using a novel MOOC platform (eLDa by providing study options (either via a self-directed learning or instructor-led learning using a novel learning tool. In view of this, the research presents general description of self-regulated learning and explored the various existing dimensions used to expose the learners SRL skills. Drawing comparison of the online tool, the results and findings of the data were analysed. The study dis¬cusses how the various dimensions contributed to the knowledge representation of the self-regulated learning abilities shown by the learners. We present how these SRL dimensions captured using the measuring instrument contributes to our growing understanding of the distinctive features of the individual learner’s self-regulated learning. MOOCs success required a high performance of self-regulated learning abilities which at the moment very little has shown these degree of supporting SRL skills. This paper presents preliminary evaluation of a novel e-learning tool known, as ‘eLDa’ developed to implement this investi¬gation of self-regulation of learning. The research applied a modified online self-regulated learning questionnaire (OSLQ as the instrument to measure the SRL skills. The modified questionnaire known as MOOC OSLQ (MOSLQ was developed with a 19-item scale questions that exposes the six SRL dimensions used in this study.

  2. New Scheme for Seamless Operation for Stand-Alone Power Systems

    Directory of Open Access Journals (Sweden)

    Hyun-Jun Kim

    2016-06-01

    Full Text Available On remote islands photovoltaic (PV panels with battery energy storage systems (BESSs supply electric power to customers in parallel operation with engine generators (EGs to reduce fuel consumption and environmental burden. A BESS operates in voltage control mode when it supplies power to loads alone, while it operates in current control mode when it supplies power to loads in parallel with the EG. This paper proposes a smooth mode change of the BESS from current control to voltage control by using initial value at the output of integral part in the voltage controller, and a smooth mode change from voltage control to current control by tracking the EG output voltage to the BESS output voltage using a phase-locked loop (PLL. The feasibility of the proposed scheme was verified through computer simulations and experiments with a scaled prototype.

  3. Feedforward control strategy for the state-decoupling Stand-alone UPS with LC output filter

    DEFF Research Database (Denmark)

    Lu, Jinghang; Savaghebi, Mehdi; Guerrero, Josep M.

    2017-01-01

    . In order to further increase the load current disturbance rejection capability of the state-decoupling in UPS system, a feedforward control strategy is proposed. In addition, the design principle for the current and voltage regulators are discussed. Simulation and experimental results are provided......In this paper, the disturbance rejection performance of the cascaded control strategy for UPS system is investigated. The comparison of closed loop system performance between conventional cascaded control (CCC) strategy and state-decoupling cascaded control (SDCC) strategy are further explored...

  4. APT - NASA ENHANCED VERSION OF AUTOMATICALLY PROGRAMMED TOOL SOFTWARE - STAND-ALONE VERSION

    Science.gov (United States)

    Premo, D. A.

    1994-01-01

    The APT code is one of the most widely used software tools for complex numerically controlled (N/C) machining. APT is an acronym for Automatically Programmed Tools and is used to denote both a language and the computer software that processes that language. Development of the APT language and software system was begun over twenty years ago as a U. S. government sponsored industry and university research effort. APT is a "problem oriented" language that was developed for the explicit purpose of aiding the N/C machine tools. Machine-tool instructions and geometry definitions are written in the APT language to constitute a "part program." The APT part program is processed by the APT software to produce a cutter location (CL) file. This CL file may then be processed by user supplied post processors to convert the CL data into a form suitable for a particular N/C machine tool. This June, 1989 offering of the APT system represents an adaptation, with enhancements, of the public domain version of APT IV/SSX8 to the DEC VAX-11/780 for use by the Engineering Services Division of the NASA Goddard Space Flight Center. Enhancements include the super pocket feature which allows concave and convex polygon shapes of up to 40 points including shapes that overlap, that leave islands of material within the pocket, and that have one or more arcs as part of the pocket boundary. Recent modifications to APT include a rework of the POCKET subroutine and correction of an error that prevented the use within a macro of a macro variable cutter move statement combined with macro variable double check surfaces. Former modifications included the expansion of array and buffer sizes to accommodate larger part programs, and the insertion of a few user friendly error messages. The APT system software on the DEC VAX-11/780 is organized into two separate programs: the load complex and the APT processor. The load complex handles the table initiation phase and is usually only run when changes to the APT processor capabilities are made. This phase initializes character recognition and syntax tables for the APT processor by creating FORTRAN block data programs. The APT processor consists of four components: the translator, the execution complex, the subroutine library, and the CL editor. The translator examines each APT statement in the part program for recognizable structure and generates a new statement, or series of statements, in an intermediate language. The execution complex processes all of the definition, motion, and related statements to generate cutter location coordinates. The subroutine library contains routines defining the algorithms required to process the sequenced list of intermediate language commands generated by the translator. The CL editor re-processes the cutter location coordinates according to user supplied commands to generate a final CL file. A sample post processor is also included which translates a CL file into a form for use with a Wales Strippit Fabramatic Model 30/30 sheet metal punch. The user should be able to readily develop post processors for other N/C machine tools. The APT language is a statement oriented, sequence dependent language. With the exception of such programming techniques as looping and macros, statements in an APT program are executed in a strict first-to-last sequence. In order to provide programming capability for the broadest possible range of parts and of machine tools, APT input (and output) is generalized, as represented by 3-dimensional geometry and tools, and arbitrarily uniform, as represented by the moving tool concept and output data in absolute coordinates. A command procedure allows the user to select the desired part program, ask for a graphics file of cutter motions in IGES format, and submit the procedure as a batch job, if desired. The APT system software is written in FORTRAN 77 for batch and interactive execution and has been implemented on a DEC VAX series computer under VMS 4.4. The enhancements for this version of APT were last updated in June, 1989. The NASA adaptation, with enhancements, of the public domain version of the APT IV/SSX8 software to the DEC VAX-11/780 is available by license for a period of ten (10) years to approved licensees. The licensed program product delivered includes the APT IV/SSX8 system source code, object code, executable images, and command procedures and one set of supporting documentation. Additional copies of the supporting documentation may be purchased at any time at the price indicated below.

  5. Quantarctica: A Unique, Open, Standalone GIS Package for Antarctic Research and Education

    Science.gov (United States)

    Roth, George; Matsuoka, Kenichi; Skoglund, Anders; Melvær, Yngve; Tronstad, Stein

    2017-04-01

    The Norwegian Polar Institute has developed Quantarctica (http://quantarctica.npolar.no), an open GIS package for use by the international Antarctic community. Quantarctica includes a wide range of cartographic basemap layers, geophysical and glaciological datasets, and satellite imagery in standardized open file formats with a consistent Antarctic map projection and customized layer and labeling styles for quick, effective cartography. Quantarctica's strengths as an open science platform lie in 1) The complete, ready-to-use data package which includes full-resolution, original-quality vector and raster data, 2) A policy for freely-redistributable and modifiable data including all metadata and citations, and 3) QGIS, a free, full-featured, modular, offline-capable open-source GIS suite with a rapid and active development and support community. The Quantarctica team is actively incorporating more up-to-date, peer-reviewed, freely distributable pan-Antarctic geospatial datasets for the next version release in 2017. As part of this ongoing development, we are investigating the best approaches for quickly and seamlessly distributing new and updated data to users, storing datasets in efficient, open file formats while maintaining full data integrity, and coexisting with numerous online data portals in a way that most actively benefits the Antarctic community. A recent survey of Quantarctica users showed broad geographical adoption among Antarctic Treaty countries, including those outside the large US and UK Antarctic programs. Maps and figures produced by Quantarctica have also appeared in open-access journals and outside of the formal scientific community on popular science and GIS blogs. Our experience with the Quantarctica project has shown the tremendous value of education and outreach, not only in promoting open software, data formats, and practices, but in empowering Antarctic science groups to more effectively use GIS and geospatial data. Open practices are making a huge impact in Antarctic GIS, where individual countries have historically maintained their own restricted Antarctic geodatabases and where the next generation of scientists are entering the field with experience in using geospatial thinking for planning, visualization, and problem solving.

  6. Comparative study of adaptive controller using MIT rules and Lyapunov method for MPPT standalone PV systems

    Science.gov (United States)

    Tariba, N.; Bouknadel, A.; Haddou, A.; Ikken, N.; Omari, Hafsa El; Omari, Hamid El

    2017-01-01

    The Photovoltaic Generator have a nonlinear characteristic function relating the intensity at the voltage I = f (U) and depend on the variation of solar irradiation and temperature, In addition, its point of operation depends directly on the load that it supplies. To fix this drawback, and to extract the maximum power available to the terminal of the generator, an adaptation stage is introduced between the generator and the load to couple the two elements as perfectly as possible. The adaptation stage is associated with a command called MPPT MPPT (Maximum Power Point Tracker) whose is used to force the PVG to operate at the MPP (Maximum Power Point) under variation of climatic conditions and load variation. This paper presents a comparative study between the adaptive controller for PV Systems using MIT rules and Lyapunov method to regulate the PV voltage. The Incremental Conductance (IC) algorithm is used to extract the maximum power from the PVG by calculating the voltage Vref, and the adaptive controller is used to regulate and track quickly the PV voltage. The two methods of the adaptive controller will be compared to prove their performance by using the PSIM tools and experimental test, and the mathematical model of step-up with PVG model will be presented.

  7. A high-performance stand-alone solar PV power system for LED lighting

    KAUST Repository

    Huang, B. J.

    2010-06-01

    The present study developed a high-performance solar PV power technology for the LED lighting of a solar home system. The nMPPO (near-Maximum-Power- Point- Operation) design is employed in system design to eliminate MPPT. A feedback control system using pulse width modulation (PWM) technique was developed for battery charging control which can increase the charging capacity by 78%. For high-efficiency lighting, the LED is directly driven by battery using a PWM discharge control to eliminate a DC/DC converter. Two solar-powered LED lighting systems (50W and 100W LED) were built. The long-term outdoor tests have shown that the loss of load probability for full-night lighting requirement is zero for 50W LED and 3.6% for 100W LED. © 2010 IEEE.

  8. Development of stand-alone risk assessment software for optimized maintenance planning of power plant facilities

    International Nuclear Information System (INIS)

    Choi, Woo Sung; Song, Gee Wook; Kim, Bum Shin; Chang, Sung Ho; Lee, Sang Min

    2015-01-01

    Risk-Risk-based inspection (RBI) has been developed in order to identify risky equipment that can cause major accidents or damages in large-scale plants. This assessment evaluates the equipment's risk, categorizes their priorities based on risk level, and then determines the urgency of their maintenance or allocates maintenance resources. An earlier version of the risk-based assessment software is already installed within the equipment management system; however, the assessment is based on examination by an inspector, and the results can be influenced by his subjective judgment, rather than assessment being based on failure probability. Moreover, the system is housed within a server, which limits the inspector's work space and time, and such a system can be used only on site. In this paper, the development of independent risk-based assessment software is introduced; this software calculates the failure probability by an analytical method, and analyzes the field inspection results, as well as inspection effectiveness. It can also operate on site, since it can be installed on an independent platform, and has the ability to generate an I/O function for the field inspection results regarding the period for an optimum maintenance cycle. This program will provide useful information not only to the field users who are participating in maintenance, but also to the engineers who need to decide whether to extend the life cycle of the power machinery or replace only specific components

  9. A high-performance stand-alone solar PV power system for LED lighting

    KAUST Repository

    Huang, B. J.; Hsu, P. C.; Wu, M. S.; Chen, K.Y.

    2010-01-01

    The present study developed a high-performance solar PV power technology for the LED lighting of a solar home system. The nMPPO (near-Maximum-Power- Point- Operation) design is employed in system design to eliminate MPPT. A feedback control system

  10. Last Stand-alone Beam Test of the Hadronic End-cap Calorimeter (HEC) Finished.

    CERN Multimedia

    Oberlack, H

    One quarter of all 134 HEC modules are tested with electron, pion and muon beams: two "partial HEC wheels", three HEC1 modules and three HEC2 modules, are used in a standard setup using the HEC cryostat in the H6 beam line. The picture shows a view of the set-up in the cryostat during the installation. MC results show that in this setup the energy leakage is well under control - well below 5 %. In addition, the other three quarters of modules are tested in technical cold tests. Using calibration signals, a detailed test of the cabling, cold electronics, crosstalk and noise performance is being done. The beam tests started with four prototype modules per run in '97, when technological optimization was still the key issue. From '98 onwards, modules of the "module 0" type have been tested, typically in two run periods per year. Finally in '99 the series production has started, with first beam test of series modules in 2000. Since then 57 series modules have been cold tested, 24 of them actually in beam tests. T...

  11. Lossy Data Aggregation with Network Coding in Stand-Alone Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Madsen, Tatiana Kozlova

    2011-01-01

    in chemical plants, etc. Given resource constrained operation of a sensor network where the nodes are battery powered and buffer sizes are limited, efficient methods for in-network data storage abd it subsequent fast and reliable transmission to a gateway is desirable. To save scarse resources and to prolong......This work focuses on a special type of wireless sensor networks (WSNs) that we refer to as a stand alone network. These netwoks operate in harsh and extreme environments where data collection is done only occasionally. Typical examples include habitat monitoring systems, monitoring systems...

  12. Wind-driven stand-alone DFIG with battery and pumped hydro ...

    Indian Academy of Sciences (India)

    Renewable energy electric conversion system; induction generators; wind power generation; energy storage; power converters. ... converter, (ii) wide speed operation of wind-driven DFIG, (iii) reduced battery capacity, (iv) high energy storage using PHSP and (v) availability of continuous power to the isolated loads.

  13. Compliant lightweight non-invasive standalone “Marine Skin” tagging system

    KAUST Repository

    Nassar, Joanna M.; Khan, Sherjeel M.; Velling, Seneca J.; Diaz-Gaxiola, Andrea; Shaikh, Sohail F.; Geraldi, Nathan R.; Sevilla, Galo T.; Duarte, Carlos M.; Hussain, Muhammad Mustafa

    2018-01-01

    Current marine research primarily depends on weighty and invasive sensory equipment and telemetric network to understand the marine environment, including the diverse fauna it contains, as a function of animal behavior and size, as well as equipment

  14. Stand-alone Cosmic Muon Reconstruction Before Installation of the CMS Silicon Strip Tracker

    CERN Document Server

    Adam, W.; Dragicevic, M.; Friedl, M.; Fruhwirth, R.; Hansel, S.; Hrubec, J.; Krammer, M.; Oberegger, M.; Pernicka, M.; Schmid, S.; Stark, R.; Steininger, H.; Uhl, D.; Waltenberger, W.; Widl, E.; Van Mechelen, P.; Cardaci, M.; Beaumont, W.; de Langhe, E.; de Wolf, E.A.; Delmeire, E.; Hashemi, M.; Bouhali, O.; Charaf, O.; Clerbaux, B.; Dewulf, J.-P.; Elgammal, S.; Hammad, G.; de Lentdecker, G.; Marage, P.; Vander Velde, C.; Vanlaer, P.; Wickens, J.; Adler, V.; Devroede, O.; De Weirdt, S.; D'Hondt, J.; Goorens, R.; Heyninck, J.; Maes, J.; Mozer, Matthias Ulrich; Tavernier, S.; Van Lancker, L.; Van Mulders, P.; Villella, I.; Wastiels, C.; Bonnet, J.-L.; Bruno, G.; De Callatay, B.; Florins, B.; Giammanco, A.; Gregoire, G.; Keutgen, Th.; Kcira, D.; Lemaitre, V.; Michotte, D.; Militaru, O.; Piotrzkowski, K.; Quertermont, L.; Roberfroid, V.; Rouby, X.; Teyssier, D.; Daubie, E.; Anttila, E.; Czellar, S.; Engstrom, P.; Harkonen, J.; Karimaki, V.; Kostesmaa, J.; Kuronen, A.; Lampen, T.; Linden, T.; Luukka, P.-R.; Maenpaa, T.; Michal, S.; Tuominen, E.; Tuominiemi, J.; Ageron, M.; Baulieu, G.; Bonnevaux, A.; Boudoul, G.; Chabanat, E.; Chabert, E.; Chierici, R.; Contardo, D.; Della Negra, R.; Dupasquier, T.; Gelin, G.; Giraud, N.; Guillot, G.; Estre, N.; Haroutunian, R.; Lumb, N.; Perries, S.; Schirra, F.; Trocme, B.; Vanzetto, S.; Agram, J.-L.; Blaes, R.; Drouhin, F.; Ernenwein, J.-P.; Fontaine, J.-C.; Berst, J.-D.; Brom, J.-M.; Didierjean, F.; Goerlach, U.; Graehling, P.; Gross, L.; Hosselet, J.; Juillot, P.; Lounis, A.; Maazouzi, C.; Olivetto, C.; Strub, R.; Van Hove, P.; Anagnostou, G.; Brauer, R.; Esser, H.; Feld, L.; Karpinski, W.; Klein, K.; Kukulies, C.; Olzem, J.; Ostapchuk, A.; Pandoulas, D.; Pierschel, G.; Raupach, F.; Schael, S.; Schwering, G.; Sprenger, D.; Thomas, M.; Weber, M.; Wittmer, B.; Wlochal, M.; Beissel, F.; Bock, E.; Flugge, G.; Gillissen, C.; Hermanns, T.; Heydhausen, D.; Jahn, D.; Kaussen, G.; Linn, A.; Perchalla, L.; Poettgens, M.; Pooth, O.; Stahl, A.; Zoeller, M.H.; Buhmann, P.; Butz, E.; Flucke, G.; Hamdorf, R.; Hauk, J.; Klanner, R.; Pein, U.; Schleper, P.; Steinbruck, G.; Blum, P.; De Boer, W.; Dierlamm, A.; Dirkes, G.; Fahrer, M.; Frey, M.; Furgeri, A.; Hartmann, F.; Heier, S.; Hoffmann, K.-H.; Kaminski, J.; Ledermann, B.; Liamsuwan, T.; Muller, S.; Muller, Th.; Schilling, F.-P.; Simonis, H.-J.; Steck, P.; Zhukov, V.; Cariola, P.; De Robertis, G.; Ferorelli, R.; Fiore, L.; Preda, M.; Sala, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Creanza, D.; De Filippis, N.; De Palma, M.; Giordano, D.; Maggi, G.; Manna, N.; My, S.; Selvaggi, G.; Albergo, S.; Chiorboli, M.; Costa, S.; Galanti, M.; Giudice, N.; Guardone, N.; Noto, F.; Potenza, R.; Saizu, M.A.; Sparti, V.; Sutera, C.; Tricomi, A.; Tuve, C.; Brianzi, M.; Civinini, C.; Maletta, F.; Manolescu, F.; Meschini, M.; Paoletti, S.; Sguazzoni, G.; Broccolo, B.; Ciulli, V.; D'Alessandro, R.; Focardi, E.; Frosali, S.; Genta, C.; Landi, G.; Lenzi, P.; Macchiolo, A.; Magini, N.; Parrini, G.; Scarlini, E.; Cerati, G.; Azzi, P.; Bacchetta, N.; Candelori, A.; Dorigo, T.; Kaminsky, A.; Karaevski, S.; Khomenkov, V.; Reznikov, S.; Tessaro, M.; Bisello, D.; De Mattia, M.; Giubilato, P.; Loreti, M.; Mattiazzo, S.; Nigro, M.; Paccagnella, A.; Pantano, D.; Pozzobon, N.; Tosi, M.; Bilei, G.M.; Checcucci, B.; Fano, L.; Servoli, L.; Ambroglini, F.; Babucci, E.; Benedetti, D.; Biasini, M.; Caponeri, B.; Covarelli, R.; Giorgi, M.; Lariccia, P.; Mantovani, G.; Marcantonini, M.; Postolache, V.; Santocchia, A.; Spiga, D.; Bagliesi, G.; Balestri, G.; Berretta, L.; Bianucci, S.; Boccali, T.; Bosi, F.; Bracci, F.; Castaldi, R.; Ceccanti, M.; Cecchi, R.; Cerri, C.; Cucoanes, A .S.; Dell'Orso, R.; Dobur, D.; Dutta, S.; Giassi, A.; Giusti, S.; Kartashov, D.; Kraan, A.; Lomtadze, T.; Lungu, G.A.; Magazzu, G.; Mammini, P.; Mariani, F.; Martinelli, G.; Moggi, A.; Palla, F.; Palmonari, F.; Petragnani, G.; Profeti, A.; Raffaelli, F.; Rizzi, D.; Sanguinetti, G.; Sarkar, S.; Sentenac, D.; Serban, A.T.; Slav, A.; Soldani, A.; Spagnolo, P.; Tenchini, R.; Tolaini, S.; Venturi, A.; Verdini, P.G.; Vos, M.; Zaccarelli, L.; Avanzini, C.; Basti, A.; Benucci, L.; Bocci, A.; Cazzola, U.; Fiori, F.; Linari, S.; Massa, M.; Messineo, A.; Segneri, G.; Tonelli, G.; Azzurri, P.; Bernardini, J.; Borrello, L.; Calzolari, F.; Foa, L.; Gennai, S.; Ligabue, F.; Petrucciani, G.; Rizzi, A.; Yang, Z.; Benotto, F.; Demaria, N.; Dumitrache, F.; Farano, R.; Borgia, M.A.; Castello, R.; Costa, M.; Migliore, E.; Romero, A.; Abbaneo, D.; Abbas, M.; Ahmed, I.; Akhtar, I.; Albert, E.; Bloch, C.; Breuker, H.; Butt, S.; Buchmuller, O.; Cattai, A.; Delaere, C.; Delattre, M.; Edera, L.M.; Engstrom, P.; Eppard, M.; Gateau, M.; Gill, K.; Giolo-Nicollerat, A.-S.; Grabit, R.; Honma, A.; Huhtinen, M.; Kloukinas, K.; Kortesmaa, J.; Kottelat, L.J.; Kuronen, A.; Leonardo, N.; Ljuslin, C.; Mannelli, M.; Masetti, L.; Marchioro, A.; Mersi, S.; Michal, S.; Mirabito, L.; Muffat-Joly, J.; Onnela, A.; Paillard, C.; Pal, I.; Pernot, J.F.; Petagna, P.; Petit, P.; Piccut, C.; Pioppi, M.; Postema, H.; Ranieri, R.; Ricci, D.; Rolandi, G.; Ronga, F.; Sigaud, C.; Syed, A.; Siegrist, P.; Tropea, P.; Troska, J.; Tsirou, A.; Vander Donckt, M.; Vasey, F.; Alagoz, E.; Amsler, Claude; Chiochia, V.; Regenfus, Christian; Robmann, P.; Rochet, J.; Rommerskirchen, T.; Schmidt, A.; Steiner, S.; Wilke, L.; Church, I.; Cole, J.; Coughlan, J.; Gay, A.; Taghavi, S.; Tomalin, I.; Bainbridge, R.; Cripps, N.; Fulcher, J.; Hall, G.; Noy, M.; Pesaresi, M.; Radicci, V.; Raymond, D.M.; Sharp, P.; Stoye, M.; Wingham, M.; Zorba, O.; Goitom, I.; Hobson, P.R.; Reid, I.; Teodorescu, L.; Hanson, G.; Jeng, G.-Y.; Liu, H.; Pasztor, G.; Satpathy, A.; Stringer, R.; Mangano, B.; Affolder, K.; Affolder, T.; Allen, A.; Barge, D.; Burke, S.; Callahan, D.; Campagnari, C.; Crook, A.; D'Alfonso, M.; Dietch, J.; Garberson, Jeffrey Ford; Hale, D.; Incandela, H.; Incandela, J.; Jaditz, S.; Kalavase, P.; Kreyer, S.; Kyre, S.; Lamb, J.; Mc Guinness, C.; Mills, C.; Nguyen, H.; Nikolic, M.; Lowette, S.; Rebassoo, F.; Ribnik, J.; Richman, J.; Rubinstein, N.; Sanhueza, S.; Shah, Y.; Simms, L.; Staszak, D.; Stoner, J.; Stuart, D.; Swain, S.; Vlimant, J.-R.; White, D.; Ulmer, K.A.; Wagner, S.R.; Bagby, L.; Bhat, P.C.; Burkett, K.; Cihangir, S.; Gutsche, O.; Jensen, H.; Johnson, M.; Luzhetskiy, N.; Mason, D.; Miao, T.; Moccia, S.; Noeding, C.; Ronzhin, A.; Skup, E.; Spalding, W.J.; Spiegel, L.; Tkaczyk, S.; Yumiceva, F.; Zatserklyaniy, A.; Zerev, E.; Anghel, I.; Bazterra, V.E.; Gerber, C.E.; Khalatian, S.; Shabalina, E.; Baringer, Philip S.; Bean, A.; Chen, J.; Hinchey, C.; Martin, C.; Moulik, T.; Robinson, R.; Gritsan, A.V.; Lae, C.K.; Tran, N.V.; Everaerts, P.; Hahn, K.A.; Harris, P.; Nahn, S.; Rudolph, M.; Sung, K.; Betchart, B.; Demina, R.; Gotra, Y.; Korjenevski, S.; Miner, D.; Orbaker, D.; Christofek, L.; Hooper, R.; Landsberg, G.; Nguyen, D.; Narain, M.; Speer, T.; Tsang, K.V.

    2009-01-01

    The subsystems of the CMS silicon strip tracker were integrated and commissioned at the Tracker Integration Facility (TIF) in the period from November 2006 to July 2007. As part of the commissioning, large samples of cosmic ray data were recorded under various running conditions in the absence of a magnetic field. Cosmic rays detected by scintillation counters were used to trigger the readout of up to 15% of the final silicon strip detector, and over 4.7 million events were recorded. This document describes the cosmic track reconstruction and presents results on the performance of track and hit reconstruction as from dedicated analyses.

  15. Alignment of the CMS Silicon Strip Tracker during stand-alone Commissioning

    CERN Document Server

    Adam, W.; Dragicevic, M.; Friedl, M.; Fruhwirth, R.; Hansel, S.; Hrubec, J.; Krammer, M.; Oberegger, M.; Pernicka, M.; Schmid, S.; Stark, R.; Steininger, H.; Uhl, D.; Waltenberger, W.; Widl, E.; Van Mechelen, P.; Cardaci, M.; Beaumont, W.; de Langhe, E.; de Wolf, E.A.; Delmeire, E.; Hashemi, M.; Bouhali, O.; Charaf, O.; Clerbaux, B.; Dewulf, J.-P.; Elgammal, S.; Hammad, G.; de Lentdecker, G.; Marage, P.; Vander Velde, C.; Vanlaer, P.; Wickens, J.; Adler, V.; Devroede, O.; De Weirdt, S.; D'Hondt, J.; Goorens, R.; Heyninck, J.; Maes, J.; Mozer, Matthias Ulrich; Tavernier, S.; Van Lancker, L.; Van Mulders, P.; Villella, I.; Wastiels, C.; Bonnet, J.-L.; Bruno, G.; De Callatay, B.; Florins, B.; Giammanco, A.; Gregoire, G.; Keutgen, Th.; Kcira, D.; Lemaitre, V.; Michotte, D.; Militaru, O.; Piotrzkowski, K.; Quertermont, L.; Roberfroid, V.; Rouby, X.; Teyssier, D.; daubie, E.; Anttila, E.; Czellar, S.; Engstrom, P.; Harkonen, J.; Karimaki, V.; Kostesmaa, J.; Kuronen, A.; Lampen, T.; Linden, T.; Luukka, P.-R.; Maenaa, T.; Michal, S.; Tuominen, E.; Tuominiemi, J.; Ageron, M.; Baulieu, G.; Bonnevaux, A.; Boudoul, G.; Chabanat, E.; Chabert, E.; Chierici, R.; Contardo, D.; Della Negra, R.; Dupasquier, T.; Gelin, G.; Giraud, N.; Guillot, G.; Estre, N.; Haroutunian, R.; Lumb, N.; Perries, S.; Schirra, F.; Trocme, B.; Vanzetto, S.; Agram, J.-L.; Blaes, R.; Drouhin, F.; Ernenwein, J.-P.; Fontaine, J.-C.; Berst, J.-D.; Brom, J.-M.; Didierjean, F.; Goerlach, U.; Graehling, P.; Gross, L.; Hosselet, J.; Juillot, P.; Lounis, A.; Maazouzi, C.; Olivetto, C.; Strub, R.; Van Hove, P.; Anagnostou, G.; Brauer, R.; Esser, H.; Feld, L.; Karpinski, W.; Klein, K.; Kukulies, C.; Olzem, J.; Ostapchuk, A.; Pandoulas, D.; Pierschel, G.; Raupach, F.; Schael, S.; Schwering, G.; Sprenger, D.; Thomas, M.; Weber, M.; Wittmer, B.; Wlochal, M.; Beissel, F.; Bock, E.; Flugge, G.; Gillissen, C.; Hermanns, T.; Heydhausen, D.; Jahn, D.; Kaussen, G.; Linn, A.; Perchalla, L.; Poettgens, M.; Pooth, O.; Stahl, A.; Zoeller, M.H.; Buhmann, P.; Butz, E.; Flucke, G.; Hamdorf, R.; Hauk, J.; Klanner, R.; Pein, U.; Schleper, P.; Steinbruck, G.; Blum, P.; De Boer, W.; Dierlamm, A.; Dirkes, G.; Fahrer, M.; Frey, M.; Furgeri, A.; Hartmann, F.; Heier, S.; Hoffmann, K.-H.; Kaminski, J.; Ledermann, B.; Liamsuwan, T.; Muller, S.; Muller, Th.; Schilling, F.-P.; Simonis, H.-J.; Steck, P.; Zhukov, V.; Cariola, P.; De Robertis, G.; Ferorelli, R.; Fiore, L.; Preda, M.; Sala, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Creanza, D.; De Filippis, N.; De Palma, M.; Giordano, D.; Maggi, G.; Manna, N.; My, S.; Selvaggi, G.; Albergo, S.; Chiorboli, M.; Costa, S.; Galanti, M.; Giudice, N.; Guardone, N.; Noto, F.; Potenza, R.; Saizu, M.A.; Sparti, V.; Sutera, C.; Tricomi, A.; Tuve, C.; Brianzi, M.; Civinini, C.; Maletta, F.; Manolescu, F.; Meschini, M.; Paoletti, S.; Sguazzoni, G.; Broccolo, B.; Ciulli, V.; D'Alessandro, R.; Focardi, E.; Frosali, S.; Genta, C.; Landi, G.; Lenzi, P.; Macchiolo, A.; Magini, N.; Parrini, G.; Scarlini, E.; Cerati, G.; Azzi, P.; Bacchetta, N.; Candelori, A.; Dorigo, T.; Kaminsky, A.; Karaevski, S.; Khomenkov, V.; Reznikov, S.; Tessaro, M.; Bisello, D.; De Mattia, M.; Giubilato, P.; Loreti, M.; Mattiazzo, S.; Nigro, M.; Paccagnella, A.; Pantano, D.; Pozzobon, N.; Tosi, M.; Bilei, G.M.; Checcucci, B.; Fano, L.; Servoli, L.; Ambroglini, F.; Babucci, E.; Benedetti, D.; Biasini, M.; Caponeri, B.; Covarelli, R.; Giorgi, M.; Lariccia, P.; Mantovani, G.; Marcantonini, M.; Postolache, V.; Santocchia, A.; Spiga, D.; Bagliesi, G.; Balestri, G.; Berretta, L.; Bianucci, S.; Boccali, T.; Bosi, F.; Bracci, F.; Castaldi, R.; Ceccanti, M.; Cecchi, R.; Cerri, C.; Cucoanes, A.S.; Dell'Orso, R.; Dobur, D.; Dutta, S.; Giassi, A.; Giusti, S.; Kartashov, D.; Kraan, A.; Lomtadze, T.; Lungu, G.A.; Magazzu, G.; Mammini, P.; Mariani, F.; Martinelli, G.; Moggi, A.; Palla, F.; Palmonari, F.; Petragnani, G.; Profeti, A.; Raffaelli, F.; Rizzi, D.; Sanguinetti, G.; Sarkar, S.; Sentenac, D.; Serban, A.T.; Slav, A.; Soldani, A.; Spagnolo, P.; Tenchini, R.; Tolaini, S.; Venturi, A.; Verdini, P.G.; Vos, M.; Zaccarelli, L.; Avanzini, C.; Basti, A.; Benucci, L.; Bocci, A.; Cazzola, U.; Fiori, F.; Linari, S.; Massa, M.; Messineo, A.; Segneri, G.; Tonelli, G.; Azzurri, P.; Bernardini, J.; Borrello, L.; Calzolari, F.; Foa, L.; Gennai, S.; Ligabue, F.; Petrucciani, G.; Rizzi, A.; Yang, Z.; Benotto, F.; Demaria, N.; Dumitrache, F.; Farano, R.; Borgia, M.A.; Castello, R.; Costa, M.; Migliore, E.; Romero, A.; Abbaneo, D.; Abbas, M.; Ahmed, I.; Akhtar, I.; Albert, E.; Bloch, C.; Breuker, H.; Butt, S.; Buchmuller, O.; Cattai, A.; Delaere, C.; Delattre, M.; Edera, L.M.; Engstrom, P.; Eppard, M.; Gateau, M.; Gill, K.; Giolo-Nicollerat, A.-S.; Grabit, R.; Honma, A.; Huhtinen, M.; Kloukinas, K.; Kortesmaa, J.; Kottelat, L.J.; Kuronen, A.; Leonardo, N.; Ljuslin, C.; Mannelli, M.; Masetti, L.; Marchioro, A.; Mersi, S.; Michal, S.; Mirabito, L.; Muffat-Joly, J.; Onnela, A.; Paillard, C.; Pal, I.; Pernot, J.F.; Petagna, P.; Petit, P.; Piccut, C.; Pioppi, M.; Postema, H.; Ranieri, R.; Ricci, D.; Rolandi, G.; Ronga, F.; Sigaud, C.; Syed, A.; Siegrist, P.; Tropea, P.; Troska, J.; Tsirou, A.; Vander Donckt, M.; Vasey, F.; Alagoz, E.; Amsler, Claude; Chiochia, V.; Regenfus, Christian; Robmann, P.; Rochet, J.; Rommerskirchen, T.; Schmidt, A.; Steiner, S.; Wilke, L.; Church, I.; Cole, J.; Coughlan, J.; Gay, A.; Taghavi, S.; Tomalin, I.; Bainbridge, R.; Cripps, N.; Fulcher, J.; Hall, G.; Noy, M.; Pesaresi, M.; Radicci, V.; Raymond, D.M.; Sharp, P.; Stoye, M.; Wingham, M.; Zorba, O.; Goitom, I.; Hobson, P.R.; Reid, I.; Teodorescu, L.; Hanson, G.; Jeng, G.-Y.; Liu, H.; Pasztor, G.; Satpathy, A.; Stringer, R.; Mangano, B.; Affolder, K.; Affolder, T.; Allen, A.; Barge, D.; Burke, S.; Callahan, D.; Campagnari, C.; Crook, A.; D'Alfonso, M.; Dietch, J.; Garberson, Jeffrey Ford; Hale, D.; Incandela, H.; Incandela, J.; Jaditz, S.; Kalavase, P.; Kreyer, S.; Kyre, S.; Lamb, J.; Mc Guinnessr, C.; Mills, C.; Nguyen, H.; Nikolic, M.; Lowette, S.; Rebassoo, F.; Ribnik, J.; Richman, J.; Rubinstein, N.; Sanhueza, S.; Shah, Y.; Simms, L.; Staszak, D.; Stoner, J.; Stuart, D.; Swain, S.; Vlimant, J.-R.; White, D.; Ulmer, K.A.; Wagner, S.R.; Bagby, L.; Bhat, P.C.; Burkett, K.; Cihangir, S.; Gutsche, O.; Jensen, H.; Johnson, M.; Luzhetskiy, N.; Mason, D.; Miao, T.; Moccia, S.; Noeding, C.; Ronzhin, A.; Skup, E.; Spalding, W.J.; Spiegel, L.; Tkaczyk, S.; Yumiceva, F.; Zatserklyaniy, A.; Zerev, E.; Anghel, I.; Bazterra, V.E.; Gerber, C.E.; Khalatian, S.; Shabalina, E.; Baringer, Philip S.; Bean, A.; Chen, J.; Hinchey, C.; Martin, C.; Moulik, T.; Robinson, R.; Gritsan, A.V.; Lae, C.K.; Tran, N.V.; Everaerts, P.; Hahn, K.A.; Harris, P.; Nahn, S.; Rudolph, M.; Sung, K.; Betchart, B.; Demina, R.; Gotra, Y.; Korjenevski, S.; Miner, D.; Orbaker, D.; Christofek, L.; Hooper, R.; Landsberg, G.; Nguyen, D.; Narain, M.; Speer, T.; Tsang, K.V.

    2009-01-01

    The results of the CMS tracker alignment analysis are presented using the data from cosmic tracks, optical survey information, and the laser alignment system at the Tracker Integration Facility at CERN. During several months of operation in the spring and summer of 2007, about five million cosmic track events were collected with a partially active CMS Tracker. This allowed us to perform first alignment of the active silicon modules with the cosmic tracks using three different statistical approaches; validate the survey and laser alignment system performance; and test the stability of Tracker structures under various stresses and temperatures ranging from +15C to -15C. Comparison with simulation shows that the achieved alignment precision in the barrel part of the tracker leads to residual distributions similar to those obtained with a random misalignment of 50 (80) microns in the outer (inner) part of the barrel.

  16. Particulate matter concentrations in residences: an intervention study evaluating stand-alone filters and air conditioners.

    Science.gov (United States)

    Batterman, S; Du, L; Mentz, G; Mukherjee, B; Parker, E; Godwin, C; Chin, J-Y; O'Toole, A; Robins, T; Rowe, Z; Lewis, T

    2012-06-01

    This study, a randomized controlled trial, evaluated the effectiveness of free-standing air filters and window air conditioners (ACs) in 126 low-income households of children with asthma. Households were randomized into a control group, a group receiving a free-standing HEPA filter placed in the child's sleeping area, and a group receiving the filter and a window-mounted AC. Indoor air quality (IAQ) was monitored for week-long periods over three to four seasons. High concentrations of particulate matter (PM) and carbon dioxide were frequently seen. When IAQ was monitored, filters reduced PM levels in the child's bedroom by an average of 50%. Filter use varied greatly among households and declined over time, for example, during weeks when pollutants were monitored, filter use was initially high, averaging 84±27%, but dropped to 63±33% in subsequent seasons. In months when households were not visited, use averaged only 34±30%. Filter effectiveness did not vary in homes with central or room ACs. The study shows that measurements over multiple seasons are needed to characterize air quality and filter performance. The effectiveness of interventions using free-standing air filters depends on occupant behavior, and strategies to ensure filter use should be an integral part of interventions. Environmental tobacco smoke (ETS) increased particulate matter (PM) levels by about 14 μg/m3 and was often detected using ETS-specific tracers despite restrictions on smoking in the house as reported on questionnaires administered to caregivers. PM concentrations depended on season, filter usage, relative humidity, air exchange ratios, number of children, outdoor PM levels, sweeping/dusting, and presence of a central air conditioner (AC). Free-standing air filters can be an effective intervention that provides substantial reductions in PM concentrations if the filters are used. However, filter use was variable across the study population and declined over the study duration, and thus strategies are needed to encourage and maintain use of filters. The variability in filter use suggests that exposure misclassification is a potential problem in intervention studies using filters. The installation of a room AC in the bedroom, intended to limit air exchange ratios, along with an air filter, did not lower PM levels more than the filter alone. © 2011 John Wiley & Sons A/S.

  17. A Voltage and Frequency Control Strategy for Stand-Alone Full Converter Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Andrés Peña Asensio

    2018-02-01

    Full Text Available This paper addresses the design and analysis of a voltage and frequency control (VFC strategy for full converter (FC-based wind energy conversion systems (WECSs and its applicability for the supply of an isolated load. When supplying an isolated load, the role of the back-to-back converters in the FC must change with respect to a grid-connected application. Voltage and frequency are established by the FC line side converter (LSC, while the generator side converter (GSC is responsible for maintaining constant voltage in the DC link. Thus, the roles of the converters in the WECS are inverted. Under such control strategies, the LSC will automatically supply the load power and hence, in order to maintain a stable operation of the WECS, the wind turbine (WT power must also be controlled in a load-following strategy. The proposed VFC is fully modelled and a stability analysis is performed. Then, the operation of the WECS under the proposed VFC is simulated and tested on a real-time test bench, demonstrating the performance of the VFC for the isolated operation of the WECS.

  18. An Analysis of Stand-alone GPS Quality and Simulated GNSS Quality for Road Pricing

    DEFF Research Database (Denmark)

    Zabic, Martina; Nielsen, Otto Anker

    2006-01-01

    Use of GPS for road pricing has often been suggested as the way of creating more efficient charging strategies than existing systems based on cordon lines or time use. In Denmark, Copenhagen participated with the AKTA project in the PRoGRESS programme, sponsored by the EU. The major part...... of the AKTA project was to equip 500 cars with GPS receivers. The paper presents the methods and results from a study of GPS quality in relation to road pricing in a dense urban area. The collected data from 500 cars over a two-year period in the Copenhagen region was analyzed in order to determine whether...... the stand alone GPS quality and reliability is adequate for implementation of an operational road pricing system in Copenhagen. The results from the analysis show that the satellite availability in Copenhagen is not sufficient to form the basis for a reliable operational road pricing system. The narrow...

  19. Rancang Bangun Stand-Alone Automatic Rain Gauge (ARG Berbasis Panel Surya

    Directory of Open Access Journals (Sweden)

    Zaenal Arifin

    2017-11-01

    Full Text Available Automatic Rain Gauge (ARG digunakan untuk memonitor curah hujan di suatu wilayah. ARG bekerja dengan menggunakan mikrokontroller sebagai prosesing unit dan merupakan sebuah embedded sistem (sistem yang berdiri sendiri. ARG tidak hanya diletakan pada stasiun pemantauan Badan Meteorologi, Klimatologi dan Geofisika (BMKG, namun ARG juga diletakan di daerah terpencil yang jauh dari jaringan listrik. Hal tersebut menjadi masalah karena ARG membutuhkan sumber energi listrik untuk dapat bekerja. Berdasarkan spesifikasinya, ARG membutuhkan mikrokontroller yang rendah dalam penggunaan daya serta memiliki cukup memory sebagai tempat penyimpanan data sementara. Salah satu jenis mikrokrontroller yang memenuhi spesifikasi tersebut adalah MSP430FR5969. Dari penelitian yang telah dilakukan, didapatkan hasil konsumsi daya rata – rata yang dibutuhkan oleh ARG sebesar 0.23 watt. Dengan memanfaatkan panel surya sebesar 20 watt yang dilengkapi dengan maximum power point tracking (MPPT sebagai sumber energi listrik, dapat menghasilkan daya 5,5 watt hingga 7,2 watt. Dengan perbandingan data konsumsi energi dan data yang dihasilkan dari solar panel panel, maka ARG memiliki sumber listrik mandiri untuk memenuhi kebutuhannya.

  20. Study on the optimization of stand-alone type photovoltaic systems. 2

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Man Geun; Song, Jin Soo; Kim, Boo ho; Park, I June; Jung, Meung Woong; Yoo, Kyun Joung; Kim, Hong Woo [Korea Inst. of Energy Research, Taejon (Korea, Republic of)

    1995-12-01

    The objectives of this study are to make a maximization of the operating efficiency of photovoltaic power systems, to improve stand- align PV systems design, technical operation and system analysis, and to promote technical cooperation of mutual interest in the area of IEA/PVPS program. This study aims to investigating the problems of applied photovoltaic power systems currently in operation to improve a system design, seeking remedies of individual PVPS applications to improve the system efficiency and reliability and to raise the system economics, and reporting the international movements of PV system dissemination and technical cooperation for developing countries. For the purpose of this works 1) Investigations of applications of existing photovoltaic power systems: - Photovoltaic electric sources used for expressway lamps - Optimum design of solar light with low pressure sodium lamps under 8 hours lighting a day at night by program-able electronic timer. 2) Comparative analyses of Marado PV system and propose a new reliable PV-diesel hybrid system and high efficiency operations. 3) Overall review of Hahwado 60 KWp PV system extending from 25 KWp and the remote monitoring systems for measurement of its operating results. 4) Introduction of IEA/PVPS international cooperating program, especially in task III for stand- alone PV systems and isolated islands and Exco meeting. As results, investigative findings of PVPS currently in operation and the work for improvement - Propose a prescription of Marado PV systems being blocked up by explosion of electrical demands from residence, parallel operational dual inverter with a big capacity. - There are shortage of solar generated power due to shortage of solar cell capacity that results in an increased operating time of diesel generator. Hence the insolation capacity of solar cell per household is continuously increased from the 0.5 KWp to 2 KWp in Hanwado island electrification.

  1. Investigation of heating and cooling in a stand-alone high temperature PEM fuel cell system

    International Nuclear Information System (INIS)

    Zhang, Caizhi; Yu, Tao; Yi, Jun; Liu, Zhitao; Raj, Kamal Abdul Rasheedj; Xia, Lingchao; Tu, Zhengkai; Chan, Siew Hwa

    2016-01-01

    Highlights: • Heating-up and cooling-down processes of HT-PEMFC are the mainly interested topics. • Dynamic behaviours, power and energy demand of the heating and cooling was studied. • Hybrid system based on LiFeYPO_4 battery for heating and cooling is built and tested. • The concept of combining different heating sources together is recommended. - Abstract: One key issue pertaining to the cold-start of High temperature PEM fuel cell (HT-PEMFC) is the requirement of high amount of thermal energy for heating up the stack to a temperature of 120 °C or above before it can generate electricity. Furthermore, cooling down the stack to a certain temperature (e.g. 50 °C) is necessary before stopping. In this study, the dynamic behaviours, power and energy demand of a 6 kW liquid cooled HT-PEMFC stack during heating-up, operation and cooling-down were investigated experimentally. The dynamic behaviours of fuel cell under heating-up and cooling-down processes are the mainly interested topics. Then a hybridisation of HT-PEMFC with Li-ion battery to demonstrate the synergistic effect on dynamic behaviour was conducted and validated for its feasibility. At last, the concept of combining different heating sources together is analysed to reduce the heating time of the HT-PEMFC as well.

  2. A Standalone but Not Lonely Language: Chinese Linguistic Environment and Education in Singapore Context

    Science.gov (United States)

    Min, Huang; Kangdi, Cheng

    2016-01-01

    Bilingual education policy in Singapore permits the students learn both English as working language and mother tongues, such as Chinese, as L2 anchoring to culture heritage. Starting from historical and sociolinguistic reasons, this paper is intended to provide a panoramic view of Chinese education in Singapore, clarify and compare Chinese…

  3. Analysis and optimization of hybrid excitation permanent magnet synchronous generator for stand-alone power system

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huijun, E-mail: huijun024@gmail.com [School of Instrumentation Science and Opto-electronics Engineering, Beihang University (China); Qu, Zheng; Tang, Shaofei; Pang, Mingqi [School of Instrumentation Science and Opto-electronics Engineering, Beihang University (China); Zhang, Mingju [Shanghai Aerospace Control Technology Institute, Shanghai (China)

    2017-08-15

    Highlights: • One novel permanent magnet generator structure has been proposed to reduce voltage regulation ratio. • Finite element method and equivalent circuit methods are both employed to realize rapid generator design. • Design of experiment (DOE) method is used to optimize permanent magnet shape for reduce voltage waveform distortion. • The obtained analysis and experiment results verify the proposed design methods. - Abstract: In this paper, electromagnetic design and permanent magnet shape optimization for permanent magnet synchronous generator with hybrid excitation are investigated. Based on generator structure and principle, design outline is presented for obtaining high efficiency and low voltage fluctuation. In order to realize rapid design, equivalent magnetic circuits for permanent magnet and iron poles are developed. At the same time, finite element analysis is employed. Furthermore, by means of design of experiment (DOE) method, permanent magnet is optimized to reduce voltage waveform distortion. Finally, the validity of proposed design methods is validated by the analytical and experimental results.

  4. Fuzzy Secondary Controller for Autonomous Stand-alone and Grid-connected AC Microgrid

    DEFF Research Database (Denmark)

    Neves, Rodolpho V. A.; Machado, Ricardo Q.; Oliveira, Vilma A.

    2016-01-01

    The present paper adresses the AC microgrid control issue using the hierarchical control structure and droop controllers for load sharing. Once the droop controllers impose an operation with frequency and voltage deviations, depending on the load and droop parameters, a hierarchical control...... structure must be added to change the droop controller operating points. The hierarchical controllers operate with local measurements and shared signals from communication links among the distributed generation systems connected to the microgrid. Depending on the geographical size of the microgrid......, the communication links can be economically unviable. This paper thus proposes a fuzzy secondary controller for AC microgrids to reduce the link communication dependency by using only local measurements. The simulation results show that the deviations as happened with the conventional secondary controllers can...

  5. Simulation of a stand-alone renewable hydrogen system for residential supply

    Directory of Open Access Journals (Sweden)

    Martín Hervello

    2014-01-01

    Full Text Available La simulación por ordenador es un primer paso lógico previo a la realización de un proyecto de una construcción física además de ser una herramienta para el diseño de redes de energía. Los sistemas combinados son una solución para mejorar la disponibilidad de la energía suministrada con medios renovables. El principal inconveniente de las fuentes de energías renovables es su naturaleza altamente estacional, con grandes variaciones en el tiempo que pueden impedir el uso como base de consumo y limitar las horas de máxima demanda. El objetivo de este trabajo es realizar simulaciones para comprobar la autosuficiencia energética de una vivienda unifamiliar en base a energías renovables (eólica, solar-fotovoltaica utilizando como medio de almacenamiento un sistema híbrido de baterías e hidrógeno. Para ello se ha utilizado el programa Simulink®-Matlab® teniendo en cuenta los datos meteorológicos proporcionados por METEO-Galicia. El modelo puede ser aplicado para determinar la viabilidad de implementar una red energética en regiones específicas, y predecir el flujo de energía y el comportamiento del sistema durante todo el año.

  6. Photovoltaic OLED Driver for Low-Power Stand-Alone Light-to-Light Systems

    DEFF Research Database (Denmark)

    Ploug, Rasmus Overgaard; Knott, Arnold

    2016-01-01

    of a three-port-converter for this purpose optimized for the specifications for driving an Organic Light Emitting Diode (OLED) panel intended for lighting purposes. By using a three-port-converter, featuring shared components for each conversion mode, the converter reaches 97 % efficiency at 1.8 W during...... conversion from photovoltaic panel to the battery, and 97 % in the area 1.4 W to 2 W for power delivery to the OLED....

  7. A Standalone PV System with a Hybrid P&O MPPT Optimization Technique

    Directory of Open Access Journals (Sweden)

    S. Hota

    2017-12-01

    Full Text Available In this paper a maximum power point tracking (MPPT design for a photovoltaic (PV system using a hybrid optimization technique is proposed. For maximum power transfer, maximum harvestable power from a PV cell in a dynamically changing surrounding should be known. The proposed technique is compared with the conventional Perturb and Observe (P&O technique. A comparative analysis of power-voltage and current-voltage characteristics of a PV cell with and without the MPPT module when connected to the grid was performed in SIMULINK, to demonstrate the increment in the efficiency of the PV module after using the MPPT module.

  8. Feasibility study for a standalone solar-wind-based hybrid energy system for application in Ethiopia

    International Nuclear Information System (INIS)

    Bekele, Getachew; Palm, Bjoern

    2010-01-01

    The aim of this paper is to investigate the possibility of supplying electricity from a solar-wind hybrid system to a remotely located model community detached from the main electricity grid in Ethiopia. The wind energy potential of four typical locations has been assessed in a previous article. The solar potential has also been investigated and the results are presented in detail in an accompanying article awaiting publication. For one of the sites, Addis Ababa, the results of the investigation are given here in detail. For the other sites, the results are given as sensitivity diagrams only. Based on the findings of the studies into energy potential, a feasibility study has been carried out on how to supply electricity to a model community of 200 families, which comprises 1000 people in total. The community is equipped with a community school and a health post. The electric load consists of both primary and deferrable types and comprises lighting, water pumps, radio receivers, and some clinical equipment. A software tool, Hybrid Optimization Model for Electric Renewables (HOMER) is used for the analysis. The result of the analysis is a list of feasible power supply systems, sorted according to their net present cost. Furthermore, sensitivity diagrams, showing the influence of wind speeds, PV costs, and diesel prices on the optimum solutions are also provided. (author)

  9. Stand-alone core sensitivity and uncertainty analysis of ALFRED from Monte Carlo simulations

    International Nuclear Information System (INIS)

    Pérez-Valseca, A.-D.; Espinosa-Paredes, G.; François, J.L.; Vázquez Rodríguez, A.; Martín-del-Campo, C.

    2017-01-01

    Highlights: • Methodology based on Monte Carlo simulation. • Sensitivity analysis of Lead Fast Reactor (LFR). • Uncertainty and regression analysis of LFR. • 10% change in the core inlet flow, the response in thermal power change is 0.58%. • 2.5% change in the inlet lead temperature the response is 1.87% in power. - Abstract: The aim of this paper is the sensitivity and uncertainty analysis of a Lead-Cooled Fast Reactor (LFR) based on Monte Carlo simulation of sizes up to 2000. The methodology developed in this work considers the uncertainty of sensitivities and uncertainty of output variables due to a single-input-variable variation. The Advanced Lead fast Reactor European Demonstrator (ALFRED) is analyzed to determine the behavior of the essential parameters due to effects of mass flow and temperature of liquid lead. The ALFRED core mathematical model developed in this work is fully transient, which takes into account the heat transfer in an annular fuel pellet design, the thermo-fluid in the core, and the neutronic processes, which are modeled with point kinetic with feedback fuel temperature and expansion effects. The sensitivity evaluated in terms of the relative standard deviation (RSD) showed that for 10% change in the core inlet flow, the response in thermal power change is 0.58%, and for 2.5% change in the inlet lead temperature is 1.87%. The regression analysis with mass flow rate as the predictor variable showed statistically valid cubic correlations for neutron flux and linear relationship neutron flux as a function of the lead temperature. No statistically valid correlation was observed for the reactivity as a function of the mass flow rate and for the lead temperature. These correlations are useful for the study, analysis, and design of any LFR.

  10. A new generation of multichannel seismic apparatus and its practical application in standalone and array monitoring

    Czech Academy of Sciences Publication Activity Database

    Brož, Milan; Štrunc, Jaroslav

    2011-01-01

    Roč. 8, č. 3 (2011), s. 345-352 ISSN 1214-9705 R&D Projects: GA ČR GA103/07/1522 Institutional research plan: CEZ:AV0Z30460519 Keywords : analog-to-digital converter * seismic array * weak event Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.530, year: 2011 http://www.irsm.cas.cz/abstracts/AGG/03_11/16_Broz.pdf

  11. Study on unitized inverter with photovoltaic grid-connected and stand-alone functions

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Haining; Su, Jianhui; Ding, Ming [Hefei University of Technology, Hefei (China)

    2008-07-01

    The main circuit and algorithm of unitized single phase inverter are presented, in which photovoltaic (PV) grid-connected algorithm, independency sine inverter algorithm and storage battery charge administer are all integrated basing on DSP (Digital Signal Processor). The control system identifies utility failure initiatively and then switches to independency power supply automatically. The methods of charging battery are multiform. Basing on material term to use utility or solar array to charge can optimize charge efficiency, assure the capacitance of battery and prolong life-span of battery. In addition, some results are offered basing on the prototype of a 2.5kW single phase inverter. (orig.)

  12. Converting existing Internal Combustion Generator (ICG) systems into HESs in standalone applications

    International Nuclear Information System (INIS)

    Perera, A.T.D.; Attalage, R.A.; Perera, K.K.C.K.; Dassanayake, V.P.C.

    2013-01-01

    Graphical abstract: - Highlights: • Obtained Pareto fronts of LEC, power supply reliability (PSR) and ICC/GHG emission. • Pareto surface was observed for smaller ICGs when considering LEC–PSR–GHG. • Shape of the LEC–PSR–ICC Pareto front gradually changes with ICG capacity. • Importance of multi-criterion decision-making after multi objective optimization. - Abstract: Expanding existing Internal Combustion Generator (ICG) systems by combining renewable energy sources is getting popular due to global concern on emission of green house gases (GHG) and increasing fossil fuel costs. Life cycle cost, initial capital cost (ICC), power supply reliability of the system, and GHG emission by ICG are factors to be considered in this process. Pareto front of Levelized Energy Cost (LEC)–Unmet Load Fraction (ULF)–GHG emission was taken in this study for four different expansion scenarios. Furthermore, Pareto front of ICC–LE–ULF was taken for three different expansion scenarios in order to analyze the impact of renewable energy integration. The results clearly depict that characteristics of the Pareto front varies with the scale of expansion and objectives taken for the optimization. A detailed analysis was conducted for a scale up problem with a 4 kVA ICG by using the Pareto fronts obtained

  13. Development of a stand-alone microcomputer based DOE contractor generic radiation worker safety course

    International Nuclear Information System (INIS)

    Klos, D.B.; Gardner, P.R.

    1985-01-01

    Westinghouse Hanford Company (WHC) has developed Computer Based Training (CBT) materials for radiation and industrial safety. First released for general Fast Flux Test Facility in November, 1984. This course has now been taken by nearly 350 people. Completion times for new personnel average around eight hours. The next project undertaken was construction of a Radiation Worker Safety course generic enough for use by all contractors at the Hanford site. The design process of the Hanford site course indicated that the quantity of ''DOE common material'' may be sufficient to warrant consideration of a larger target population. Specifically, the course will be designed to run on an IBM-PC or compatible computer having 256K RAM, a standard IBM color graphics card or equivalent, a color graphics monitor, and two floppy disk drives or one hard disk. The target student population includes those who routinely work in Radiation Areas, especially crafts people. We are not targeting Health Physics personnel, except, possibly, for introductory training, nor are we directing the course toward ''casual'' or escorted workers

  14. Study of applying a hybrid standalone wind-photovoltaic generation system

    Directory of Open Access Journals (Sweden)

    Aissa Dahmani

    2015-01-01

    Full Text Available The purpose of this paper is the study of applying a hybrid system wind/photovoltaic to supply a community in southern Algeria. Diesel generators are always used to provide such remote regions with energy. Using renewable energy resources is a good alternative to overcome such pollutant generators. Hybrid Optimization Model for Electric Renewable (HOMER software is used to determine the economic feasibility of the proposed configuration. Assessment of renewable resources consisting in wind and solar potentials, load profile determination and sensitivity of different parameters analysis were performed. The cost of energy (COE of 0.226 $/kWh is very competitive with those found in literature.

  15. Comparing Memory-Efficient Genome Assemblers on Stand-Alone and Cloud Infrastructures

    KAUST Repository

    Kleftogiannis, Dimitrios A.; Kalnis, Panos; Bajic, Vladimir B.

    2013-01-01

    methodologies, we propose two general assembly strategies that can improve short-read assembly approaches and result in reduction of the memory footprint. Finally, we discuss the possibility of utilizing cloud infrastructures for genome assembly and we comment

  16. PV led engine characterization lab for standalone light to light systems

    DEFF Research Database (Denmark)

    Thorsteinsson, Sune; Poulsen, Peter Behrensdorff; Lindén, Johannes

    2014-01-01

    PV-powered lighting systems, light-to-light systems (L2L), offer outdoor lighting where it is else where cumbersome to enable lighting. Application of these systems at high latitudes, where the difference in day length between summer and winter is large and the solar energy is low requires smart...... dimming functions for reliable lighting. In this work we have built a laboratory to characterize these systems up to 200 Wp from “nose to tail” in great details to support improvement of the systems and to make accurate field performance predictions....

  17. An ArcGIS analysis of Stand-alone GPS quality for Road Pricing

    DEFF Research Database (Denmark)

    Zabic, Martina

    2006-01-01

    The paper presents the methods and some of the result maps from a study of GPS quality in relation to road pricing in a dense urban area. Data from 500 cars were colleted over a two-year period in the Copenhagen region (Denmark). The data was analyzed in ArcGIS in order to determine whether the GPS...... quality and reliability is adequate for implementation of a road pricing system. The GPS log files was imported into ArcGIS and analyzed in relation to the digital road network and the density of the high rise areas in order to examine where the high buildings and narrow street canyons causes too many...

  18. A Challenge for Developers: Preserving the Interactivity of Human Relations in a Standalone Application.

    Science.gov (United States)

    Mazur, F. E.

    1993-01-01

    Describes the efforts taken by the Cornell Interactive Theater Ensemble to provide interactive human relations training on date rape using live dramatizations, video with facilitated audience participation, and an electronic multimedia format with decision trees for interactive involvement. (EA)

  19. SAMAC program: the computer support for a stand-alone monitoring and control system

    International Nuclear Information System (INIS)

    Logg, C.A.

    1979-12-01

    The high energy physics experiments at SLAC require constant monitoring and control of the numerous components contained in the particle detection apparatus. This paper describes a basic hardware configuration and operating system which have been designed and implemented to satisfy the monitoring and control requirements of the many different setups used in these high energy physics experiments. It is based on the LSI-11 microprocessor with up to one million words of RAM and EPROM which are interchangeably mappable into the normal LSI-11 RAM/EPROM address space of 28K words. The entire system is modular in hardware and software so that it can easily be tailored to an individual experiment. The human interface is such that little training is required for effective use of the system

  20. Stand-alone and Interdisciplinary Course Design for Engineering Education for Sustainable Development

    DEFF Research Database (Denmark)

    Arsat, M.; Holgaard, Jette Egelund; de Graaff, Erik

    discipline or to fit across programmes. At Aalborg University (AAU), Denmark, which has a long tradition of problem based learning (PBL), a comprehensive sustainability course has been introduced to fit all students not at least across programmes but also across faculties of engineering, humanities...

  1. Key factors for the implementation of successful, stand-alone village electrification schemes in Peru

    Science.gov (United States)

    Sanchez-Campos, Teodoro

    The hypothesis of this work is that there are social, financial, technical, managerial institutional and political key factors that may either support or prevent the success of small stand alone energy systems in rural areas. This research work aims at contributing to the identification of such factors and study their relevance to the performance and sustainability of stand alone energy systems in rural areas; to meet its purpose, a wide range of literature was reviewed including rural electrification programmes and projects, research and development projects on access to electricity in rural areas, impact studies and others, and a field research survey was done the Andes and Upper Jungle regions in Peru. Nineteen possible critical factors were identified, thirteen with relevance at the local context (the community or village), and six with relevance at the national (or wider) context. From literature review it was found that the possible local critical factors were relevant only to four categories of factors instead of the six considered initially (i.e. social, financial, technological and managerial): the other two categories, political and institutional were found to be more relevant to the national context, therefore those were included in the group of possible critical factors of wider context. A series of questionnaires were designed to collect field data information, which was later used to analyse and establish the relation of each identified factor with the success of the systems studied. The survey research was implemented in 14 villages, 7 with small diesel sets and 7 with small hydropower schemes, all spread in the Andes and Upper Jungle of Peru, which were carefully selected to be representative of regions with isolated stand alone systems and with different socioeconomic background. Out of the 13 possible critical factors of local context, it was found that only 3 are really critical, the others are important but not critical; one of them (technical assistance) was found to be closely linked to national capacity, therefore for practical reasons both are considered as one critical factor or wider context. Although more research study is needed to establish a more clearer result on the factors of wider context (national context), it was found that out of the 6 factors of wider context only one appears to be critical, the other 5 are important but not critical. Therefore the summary of critical factors is as follows: a) Critical Factors of Local Context o Management o Local capacity b) Critical Factors of National Context o Technical Support/national capacity On the local factors, management appears to be the most critical of all factors, because with good management, most of the other factors can be overcome. It was also found that "The small enterprise model" tested by Practical Action on small scale hydropower schemes is proving to be successful and other organisations are starting to use it in different contexts. Therefore future research is recommended on this particular management model in order to be useful for rural electrification programmes based on decentralised energy generation systems.

  2. Simulation of Iodine Behavior by Coupling of a Standalone Model with MELCOR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Han Chul; Cho, Song Won [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2012-05-15

    During a severe accident, a large fraction of iodine in the core can be released into the containment. Iodine is important in terms of its high activity in the early phase after a core-melt accident due to its short half-life isotopes and its serious effect on the public health, especially on the thyroid. Therefore, iodine behavior has been extensively studied through the international research programs. Major research areas are iodine chemistry, surface reactions, mass transfer, modeling of iodine chemistry and its applications to severe accident assessment, and accident management. Advanced tools for modeling these phenomena have been developed and validated by several experiments such as ISTP-EPICUR (International Source Term Program - Experimental Program on Iodine Chemistry under Radiation) and PARIS, and OECD-BIP (Behavior of Iodine Project) in which Korea Institute of Nuclear Safety (KINS) has been participating. As a result, a simple iodine model, RAIM (Radio-Active Iodine chemistry Model) was developed, based on the IMOD methodology in order to deal with organic iodides conveniently. RAIM has been also coupled with MELCOR, replacing the pool chemistry model (PCM). This coupling model, MELCOR-RAIM, will be used for an integrated severe accident assessment that takes into account the organic iodine behavior. This model is described herein, and representative simulation results of the model are presented

  3. Battery Storage Technologies for Electrical Applications: Impact in Stand-Alone Photovoltaic Systems

    OpenAIRE

    Daniel Akinyele; Juri Belikov; Yoash Levron

    2017-01-01

    Batteries are promising storage technologies for stationary applications because of their maturity, and the ease with which they are designed and installed compared to other technologies. However, they pose threats to the environment and human health. Several studies have discussed the various battery technologies and applications, but evaluating the environmental impact of batteries in electrical systems remains a gap that requires concerted research efforts. This study first presents an ove...

  4. Analysis and optimization of hybrid excitation permanent magnet synchronous generator for stand-alone power system

    International Nuclear Information System (INIS)

    Wang, Huijun; Qu, Zheng; Tang, Shaofei; Pang, Mingqi; Zhang, Mingju

    2017-01-01

    Highlights: • One novel permanent magnet generator structure has been proposed to reduce voltage regulation ratio. • Finite element method and equivalent circuit methods are both employed to realize rapid generator design. • Design of experiment (DOE) method is used to optimize permanent magnet shape for reduce voltage waveform distortion. • The obtained analysis and experiment results verify the proposed design methods. - Abstract: In this paper, electromagnetic design and permanent magnet shape optimization for permanent magnet synchronous generator with hybrid excitation are investigated. Based on generator structure and principle, design outline is presented for obtaining high efficiency and low voltage fluctuation. In order to realize rapid design, equivalent magnetic circuits for permanent magnet and iron poles are developed. At the same time, finite element analysis is employed. Furthermore, by means of design of experiment (DOE) method, permanent magnet is optimized to reduce voltage waveform distortion. Finally, the validity of proposed design methods is validated by the analytical and experimental results.

  5. The Small, Stand-Alone Early College: Impact on High School Outcomes

    Science.gov (United States)

    Glennie, Elizabeth; Unlu, Fatih; Furey, Jane

    2016-01-01

    North Carolina's Early College model is the subject of an IES-funded eleven-year longitudinal experimental study that utilized a lottery process to assign early college applicants to either treatment or control groups. This paper presents findings related to high school outcomes. The primary goal of the early college model is to increase the…

  6. The Small, Stand-Alone Early College: Impact on Postsecondary Outcomes

    Science.gov (United States)

    Unlu, Fatih; Furey, Jane

    2016-01-01

    This paper presents results from the longitudinal experimental study conducted on North Carolina's early college model described in an earlier paper. The primary purpose of this paper is to present the impact of the early college model on outcomes related to postsecondary enrollment. The specific research questions driving this study include: (1)…

  7. Feasibility study for a standalone solar-wind-based hybrid energy system for application in Ethiopia

    Energy Technology Data Exchange (ETDEWEB)

    Bekele, Getachew; Palm, Bjoern [Department of Energy Technology, KTH, Stockholm (Sweden)

    2010-02-15

    The aim of this paper is to investigate the possibility of supplying electricity from a solar-wind hybrid system to a remotely located model community detached from the main electricity grid in Ethiopia. The wind energy potential of four typical locations has been assessed in a previous article. The solar potential has also been investigated and the results are presented in detail in an accompanying article awaiting publication. For one of the sites, Addis Ababa, the results of the investigation are given here in detail. For the other sites, the results are given as sensitivity diagrams only. Based on the findings of the studies into energy potential, a feasibility study has been carried out on how to supply electricity to a model community of 200 families, which comprises 1000 people in total. The community is equipped with a community school and a health post. The electric load consists of both primary and deferrable types and comprises lighting, water pumps, radio receivers, and some clinical equipment. A software tool, Hybrid Optimization Model for Electric Renewables (HOMER) is used for the analysis. The result of the analysis is a list of feasible power supply systems, sorted according to their net present cost. Furthermore, sensitivity diagrams, showing the influence of wind speeds, PV costs, and diesel prices on the optimum solutions are also provided. (author)

  8. Development of a low cost test rig for standalone WECS subject to electrical faults.

    Science.gov (United States)

    Himani; Dahiya, Ratna

    2016-11-01

    In this paper, a contribution to the development of low-cost wind turbine (WT) test rig for stator fault diagnosis of wind turbine generator is proposed. The test rig is developed using a 2.5kW, 1750 RPM DC motor coupled to a 1.5kW, 1500 RPM self-excited induction generator interfaced with a WT mathematical model in LabVIEW. The performance of the test rig is benchmarked with already proven wind turbine test rigs. In order to detect the stator faults using non-stationary signals in self-excited induction generator, an online fault diagnostic technique of DWT-based multi-resolution analysis is proposed. It has been experimentally proven that for varying wind conditions wavelet decomposition allows good differentiation between faulty and healthy conditions leading to an effective diagnostic procedure for wind turbine condition monitoring. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  9. Stand-alone error characterisation of microwave satellite soil moisture using a Fourier method

    Science.gov (United States)

    Error characterisation of satellite-retrieved soil moisture (SM) is crucial for maximizing their utility in research and applications in hydro-meteorology and climatology. Error characteristics can provide insights for retrieval development and validation, and inform suitable strategies for data fus...

  10. A stand-alone track reconstruction algorithm for the scintillating fibre tracker at the LHCb upgrade

    CERN Multimedia

    Quagliani, Renato

    2017-01-01

    The LHCb upgrade detector project foresees the presence of a scintillating fiber tracker (SciFi) to be used during the LHC Run III, starting in 2020. The instantaneous luminosity will be increased up to $2\\times10^{33}$, five times larger than in Run II and a full software event reconstruction will be performed at the full bunch crossing rate by the trigger. The new running conditions, and the tighter timing constraints in the software trigger, represent a big challenge for track reconstruction. This poster presents the design and performance of a novel algorithm that has been developed to reconstruct track segments using solely hits from the SciFi. This algorithm is crucial for the reconstruction of tracks originating from long-lived particles such as $K_{S}^{0}$ and $\\Lambda$ and allows to greatly enhance the physics potential and capabilities of the LHCb upgrade when compared to its previous implementation.

  11. Comparing Memory-Efficient Genome Assemblers on Stand-Alone and Cloud Infrastructures

    KAUST Repository

    Kleftogiannis, Dimitrios A.

    2013-09-27

    A fundamental problem in bioinformatics is genome assembly. Next-generation sequencing (NGS) technologies produce large volumes of fragmented genome reads, which require large amounts of memory to assemble the complete genome efficiently. With recent improvements in DNA sequencing technologies, it is expected that the memory footprint required for the assembly process will increase dramatically and will emerge as a limiting factor in processing widely available NGS-generated reads. In this report, we compare current memory-efficient techniques for genome assembly with respect to quality, memory consumption and execution time. Our experiments prove that it is possible to generate draft assemblies of reasonable quality on conventional multi-purpose computers with very limited available memory by choosing suitable assembly methods. Our study reveals the minimum memory requirements for different assembly programs even when data volume exceeds memory capacity by orders of magnitude. By combining existing methodologies, we propose two general assembly strategies that can improve short-read assembly approaches and result in reduction of the memory footprint. Finally, we discuss the possibility of utilizing cloud infrastructures for genome assembly and we comment on some findings regarding suitable computational resources for assembly.

  12. Experimental stand-alone self-excited induction generator driven by a diesel motor

    Directory of Open Access Journals (Sweden)

    Mhamdi Taoufik

    2017-12-01

    Full Text Available This paper presents an experimental work to design and size a diesel generator (DG. The basic system is equipped with a 1.5 kW self-excited induction generator (SEIG, a diesel motor (DM, a static voltage compensator (SVC and controllers. A proportional integral controller is used to meet the requirement of the SEIG frequency regulation. A controlled voltage source is performed by using an SVC with a fuzzy controller, which adjusts voltage by varying the amount of the injected reactive power. An experimental set-up is used to identify the SEIG parameters and select the convenient bank of capacitors that minimize the SEIG starting up time and fix the convenient margin of voltage. The system has been tested by simulation using models implemented by Matlab/Simulink software. The simulation results confirm the efficiency of the proposed strategy of voltage regulation. Keywords: Diesel motor, SEIG, SVC, Voltage regulation, Frequency regulation

  13. SSTAR, a Stand-Alone Easy-To-Use Antimicrobial Resistance Gene Predictor.

    Science.gov (United States)

    de Man, Tom J B; Limbago, Brandi M

    2016-01-01

    We present the easy-to-use Sequence Search Tool for Antimicrobial Resistance, SSTAR. It combines a locally executed BLASTN search against a customizable database with an intuitive graphical user interface for identifying antimicrobial resistance (AR) genes from genomic data. Although the database is initially populated from a public repository of acquired resistance determinants (i.e., ARG-ANNOT), it can be customized for particular pathogen groups and resistance mechanisms. For instance, outer membrane porin sequences associated with carbapenem resistance phenotypes can be added, and known intrinsic mechanisms can be included. Unique about this tool is the ability to easily detect putative new alleles and truncated versions of existing AR genes. Variants and potential new alleles are brought to the attention of the user for further investigation. For instance, SSTAR is able to identify modified or truncated versions of porins, which may be of great importance in carbapenemase-negative carbapenem-resistant Enterobacteriaceae. SSTAR is written in Java and is therefore platform independent and compatible with both Windows and Unix operating systems. SSTAR and its manual, which includes a simple installation guide, are freely available from https://github.com/tomdeman-bio/Sequence-Search-Tool-for-Antimicrobial-Resistance-SSTAR-. IMPORTANCE Whole-genome sequencing (WGS) is quickly becoming a routine method for identifying genes associated with antimicrobial resistance (AR). However, for many microbiologists, the use and analysis of WGS data present a substantial challenge. We developed SSTAR, software with a graphical user interface that enables the identification of known AR genes from WGS and has the unique capacity to easily detect new variants of known AR genes, including truncated protein variants. Current software solutions do not notify the user when genes are truncated and, therefore, likely nonfunctional, which makes phenotype predictions less accurate. SSTAR users can apply any AR database of interest as a reference comparator and can manually add genes that impact resistance, even if such genes are not resistance determinants per se (e.g., porins and efflux pumps).

  14. Porous silicon with embedded tritium as a stand-alone prime power source for optoelectronic applications

    International Nuclear Information System (INIS)

    Tam, S.W.

    1997-01-01

    Disclosed is an illumination source comprising a porous silicon having a source of electrons on the surface and/or interstices thereof having a total porosity in the range of from about 50 v/o to about 90 v/o. Also disclosed are a tritiated porous silicon and a photovoltaic device and an illumination source of tritiated porous silicon. 1 fig

  15. Porous silicon with embedded tritium as a stand-alone prime power source for optoelectronic applications

    Science.gov (United States)

    Tam, Shiu-Wing

    1997-01-01

    An illumination source comprising a porous silicon having a source of electrons on the surface and/or interticies thereof having a total porosity in the range of from about 50 v/o to about 90 v/o. Also disclosed are a tritiated porous silicon and a photovoltaic device and an illumination source of tritiated porous silicon.

  16. Compliant lightweight non-invasive standalone “Marine Skin” tagging system

    KAUST Repository

    Nassar, Joanna M.

    2018-04-16

    Current marine research primarily depends on weighty and invasive sensory equipment and telemetric network to understand the marine environment, including the diverse fauna it contains, as a function of animal behavior and size, as well as equipment longevity. To match animal morphology and activity within the surrounding marine environment, here we show a physically flexible and stretchable skin-like and waterproof autonomous multifunctional system, integrating Bluetooth, memory chip, and high performance physical sensors. The sensory tag is mounted on a swimming crab (Portunus pelagicus) and is capable of continuous logging of depth, temperature, and salinity within the harsh ocean environment. The fully packaged, ultra-lightweight (<2.4 g in water), and compliant “Marine Skin” system does not have any wired connection enabling safe and weightless cutting-edge approach to monitor and assess marine life and the ecosystem’s health to support conservation and management of marine ecosystems.

  17. The Politics of Education: Why Stand-Alone Youth Work Degrees Matter

    Science.gov (United States)

    Bessant, Judith

    2007-01-01

    While the demand in Australia for youth workers is growing, the education of youth workers in universities is being "rationalised" because these institutions have been fiscally squeezed by successive federal governments. What are the consequences for youth workers, young people and society as a whole if the move towards…

  18. Comparing memory-efficient genome assemblers on stand-alone and cloud infrastructures.

    Science.gov (United States)

    Kleftogiannis, Dimitrios; Kalnis, Panos; Bajic, Vladimir B

    2013-01-01

    A fundamental problem in bioinformatics is genome assembly. Next-generation sequencing (NGS) technologies produce large volumes of fragmented genome reads, which require large amounts of memory to assemble the complete genome efficiently. With recent improvements in DNA sequencing technologies, it is expected that the memory footprint required for the assembly process will increase dramatically and will emerge as a limiting factor in processing widely available NGS-generated reads. In this report, we compare current memory-efficient techniques for genome assembly with respect to quality, memory consumption and execution time. Our experiments prove that it is possible to generate draft assemblies of reasonable quality on conventional multi-purpose computers with very limited available memory by choosing suitable assembly methods. Our study reveals the minimum memory requirements for different assembly programs even when data volume exceeds memory capacity by orders of magnitude. By combining existing methodologies, we propose two general assembly strategies that can improve short-read assembly approaches and result in reduction of the memory footprint. Finally, we discuss the possibility of utilizing cloud infrastructures for genome assembly and we comment on some findings regarding suitable computational resources for assembly.

  19. Single-crate stand-alone CAMAC control system for a negative ion source test facility

    International Nuclear Information System (INIS)

    Juras, R.C.; Ziegler, N.F.

    1979-01-01

    A single-crate CAMAC system was configured to control a negative ion source development facility at ORNL and control software was written for the crate microcomputer. The software uses inputs from a touch panel and a shaft encoder to control the various operating parameters of the test facility and uses the touch panel to display the operating status. Communication to and from the equipment at ion source potential is accomplished over optical fibers from an ORNL-built CAMAC module. A receiver at ion source potential stores the transmitted data and some of these stored values are then used to control discrete parameters of the ion source (i.e., power supply on or off). Other stored values are sent to a multiplexed digital-to-analog converter to provide analog control signals. A transmitter at ion source potential transmits discrete status information and several channels of analog data from an analog-to-digital converter back to the ground-potential receiver where it is stored to be read and displayed by the software

  20. Control aspects of the Schuchuli Village stand-alone photovoltaic power system

    Science.gov (United States)

    Groumpos, P. P.; Culler, J. E.; Delombard, R.

    1984-11-01

    A photovoltaic power system in an Arizona Indian village was installed. The control subsystem of this photovoltaic power system was analyzed. The four major functions of the control subsystem are: (1) voltage regulation; (2) load management; (3) water pump control; and (4) system protection. The control subsystem functions flowcharts for the control subsystem operation, and a computer program that models the control subsystem are presented.

  1. An Approach for High-precision Stand-alone Positioning in a Dynamic Environment

    Science.gov (United States)

    Halis Saka, M.; Metin Alkan, Reha; Ozpercin, Alişir

    2015-04-01

    In this study, an algorithm is developed for precise positioning in dynamic environment utilizing a single geodetic GNSS receiver using carrier phase data. In this method, users should start the measurement on a known point near the project area for a couple of seconds making use of a single dual-frequency geodetic-grade receiver. The technique employs iono-free carrier phase observations with precise products. The equation of the algorithm is given below; Sm(t(i+1))=SC(ti)+[ΦIF (t(i+1) )-ΦIF (ti)] where, Sm(t(i+1)) is the phase-range between satellites and the receiver, SC(ti) is the initial range computed from the initial known point coordinates and the satellite coordinates and ΦIF is the ionosphere-free phase measurement (in meters). Tropospheric path delays are modelled using the standard tropospheric model. To accomplish the process, an in-house program was coded and some functions were adopted from Easy-Suite available at http://kom.aau.dk/~borre/easy. In order to assess the performance of the introduced algorithm in a dynamic environment, a dataset from a kinematic test measurement was used. The data were collected from a kinematic test measurement in Istanbul, Turkey. In the test measurement, a geodetic dual-frequency GNSS receiver, Ashtech Z-Xtreme, was set up on a known point on the shore and a couple of epochs were recorded for initialization. The receiver was then moved to a vessel and data were collected for approximately 2.5 hours and the measurement was finalized on a known point on the shore. While the kinematic measurement on the vessel were carried out, another GNSS receiver was set up on a geodetic point with known coordinates on the shore and data were collected in static mode to calculate the reference trajectory of the vessel using differential technique. The coordinates of the vessel were calculated for each measurement epoch with the introduced method. With the purpose of obtaining more robust results, all coordinates were calculated once again by inversely, i.e. from the last epoch to the first one. In this way, the estimated coordinates were also controlled. The average of both computed coordinates were used as vessel coordinates and then compared with the known-coordinates those of geodetic receiver epoch by epoch. The results indicate that the calculated coordinates from the introduced method are consistent with the reference trajectory with an accuracy of about 1 decimeter. In contrast, the findings imply lower accuracy for height components with an accuracy of about 2 decimeters. This accuracy level meets the requirement of many applications including some marine applications, precise hydrographic surveying, dredging, attitude control of ships, buoys and floating platforms, marine geodesy, navigation and oceanography.

  2. Bifacial PV cell with reflector for stand-alone mast for sensor powering purposes

    Science.gov (United States)

    Jakobsen, Michael L.; Thorsteinsson, Sune; Poulsen, Peter B.; Riedel, N.; Rødder, Peter M.; Rødder, Kristin

    2017-09-01

    Reflectors to bifacial PV-cells are simulated and prototyped in this work. The aim is to optimize the reflector to specific latitudes, and particularly northern latitudes. Specifically, by using minimum semiconductor area the reflector must be able to deliver the electrical power required at the condition of minimum solar travel above the horizon, worst weather condition etc. We will test a bifacial PV-module with a retroreflector, and compare the output with simulations combined with local solar data.

  3. Nanosatellite High-Precision Magnetic Missions Enabled by Advances in a Stand-Alone Scalar/Vector Absolute Magnetometer

    Science.gov (United States)

    Hulot, G.; Leger, J. M.; Vigneron, P.; Jager, T.; Bertrand, F.; Coisson, P.; Deram, P.; Boness, A.; Tomasini, L.; Faure, B.

    2017-12-01

    Satellites of the ESA Swarm mission currently in operation carry a new generation of Absolute Scalar Magnetometers (ASM), which nominally deliver 1 Hz scalar for calibrating the relative flux gate magnetometers that complete the magnetometry payload (together with star cameras, STR, for attitude restitution) and providing extremely accurate scalar measurements of the magnetic field for science investigations. These ASM instruments, however, can also operate in two additional modes, a high-frequency 250 Hz scalar mode and a 1 Hz absolute dual-purpose scalar/vector mode. The 250 Hz scalar mode already allowed the detection of until now very poorly documented extremely low frequency whistler signals produced by lightning in the atmosphere, while the 1 Hz scalar/vector mode has provided data that, combined with attitude restitution from the STR, could be used to produce scientifically relevant core field and lithospheric field models. Both ASM modes have thus now been fully validated for science applications. Efforts towards developing an improved and miniaturized version of this instrument is now well under way with CNES support in the context of the preparation of a 12U nanosatellite mission (NanoMagSat) proposed to be launched to complement the Swarm satellite constellation. This advanced miniaturized ASM could potentially operate in an even more useful mode, simultaneously providing high frequency (possibly beyond 500 Hz) absolute scalar data and self-calibrated 1 Hz vector data, thus providing scientifically valuable data for multiple science applications. In this presentation, we will illustrate the science such an instrument taken on board a nanosatellite could enable, and report on the current status of the NanoMagSat project that intends to take advantage of it.

  4. An automatic time domain reflectometry device to measure and store soil water contents for stand-alone field use

    NARCIS (Netherlands)

    Elsen, van den H.G.M.; Kokot, J.; Skierucha, W.; Halbertsma, J.M.

    1995-01-01

    A field set-up was developed to measure soil moisture content on ten different positions using the time domain reflectometry (TDR) technique. The set-up works on a 12 V battery or solar panel system, independent of an external power source, has low power consumption, and compact dimensions. The

  5. A new technique based on Artificial Bee Colony Algorithm for optimal sizing of stand-alone photovoltaic system.

    Science.gov (United States)

    Mohamed, Ahmed F; Elarini, Mahdi M; Othman, Ahmed M

    2014-05-01

    One of the most recent optimization techniques applied to the optimal design of photovoltaic system to supply an isolated load demand is the Artificial Bee Colony Algorithm (ABC). The proposed methodology is applied to optimize the cost of the PV system including photovoltaic, a battery bank, a battery charger controller, and inverter. Two objective functions are proposed: the first one is the PV module output power which is to be maximized and the second one is the life cycle cost (LCC) which is to be minimized. The analysis is performed based on measured solar radiation and ambient temperature measured at Helwan city, Egypt. A comparison between ABC algorithm and Genetic Algorithm (GA) optimal results is done. Another location is selected which is Zagazig city to check the validity of ABC algorithm in any location. The ABC is more optimal than GA. The results encouraged the use of the PV systems to electrify the rural sites of Egypt.

  6. A new technique based on Artificial Bee Colony Algorithm for optimal sizing of stand-alone photovoltaic system

    Directory of Open Access Journals (Sweden)

    Ahmed F. Mohamed

    2014-05-01

    Full Text Available One of the most recent optimization techniques applied to the optimal design of photovoltaic system to supply an isolated load demand is the Artificial Bee Colony Algorithm (ABC. The proposed methodology is applied to optimize the cost of the PV system including photovoltaic, a battery bank, a battery charger controller, and inverter. Two objective functions are proposed: the first one is the PV module output power which is to be maximized and the second one is the life cycle cost (LCC which is to be minimized. The analysis is performed based on measured solar radiation and ambient temperature measured at Helwan city, Egypt. A comparison between ABC algorithm and Genetic Algorithm (GA optimal results is done. Another location is selected which is Zagazig city to check the validity of ABC algorithm in any location. The ABC is more optimal than GA. The results encouraged the use of the PV systems to electrify the rural sites of Egypt.

  7. Real-time direct cell concentration and viability determination using a fully automated microfluidic platform for standalone process monitoring

    DEFF Research Database (Denmark)

    Rodrigues de Sousa Nunes, Pedro André; Kjaerulff, S.; Dufva, Martin

    2015-01-01

    system performance by monitoring in real time the cell concentration and viability of yeast extracted directly from an in-house made bioreactor. This is the first demonstration of using the Dean drag force, generated due to the implementation of a curved microchannel geometry in conjunction with high...... flow rates, to promote passive mixing of cell samples and thus homogenization of the diluted cell plug. The autonomous operation of the fluidics furthermore allows implementation of intelligent protocols for administering air bubbles from the bioreactor in the microfluidic system, so...... and thereby ensure optimal cell production, by prolonging the fermentation cycle and increasing the bioreactor output. In this work, we report on the development of a fully automated microfluidic system capable of extracting samples directly from a bioreactor, diluting the sample, staining the cells...

  8. Fuel cells, batteries and super-capacitors stand-alone power systems management using optimal/flatness based-control

    Energy Technology Data Exchange (ETDEWEB)

    Benaouadj, M.; Aboubou, A.; Bahri, M.; Boucetta, A. [MSE Laboratory, Mohamed khiderBiskra University (Algeria); Ayad, M. Y., E-mail: ayadmy@gmail.com [R& D, Industrial Hybrid Vehicle Applications (France)

    2016-07-25

    In this work, an optimal control (under constraints) based on the Pontryagin’s maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane) fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DC-DC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithiumion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: Impose the power requested by a habitat (representing the load) according to a proposed daily consumption profile, Keep fuel cells working at optimal power delivery conditions, Maintain constant voltage across the common DC bus, Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control. Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  9. Optimal/flatness based-control of stand-alone power systems using fuel cells, batteries and supercapacitors

    Directory of Open Access Journals (Sweden)

    Mahdi Benaouadj

    2017-03-01

    Full Text Available In this work, an optimal control (under constraints based on the Pontryagin’s maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DCDC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithium-ion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: - Impose the power requested by a habitat (representing the load according to a proposed daily consumption profile, - Keep fuel cells working at optimal power delivery conditions, - Maintain constant voltage across the common DC bus, - Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control. Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  10. Contrast-enhanced MR enterography as a stand-alone tool to evaluate Crohn's disease in a paediatric population

    International Nuclear Information System (INIS)

    Spieler, B.; Hindman, N.; Levy, J.; Zabrieski, K.; Sahlein, D.; Seuss, C.; Kim, S.

    2013-01-01

    Aim: To assess the performance of contrast-enhanced T1-weighted magnetic resonance imaging (MRI) alone in the evaluation of Crohn's disease in comparison to all magnetic resonance enterography (MRE) imaging sequences together in an attempt to suggest limitation of the number of overall unenhanced sequences need for the follow-up evaluation. Materials and methods: Twenty-five paediatric patients (mean age 14.1 ± 3.7 years, male = 12, female = 13) underwent MRE at 1.5 T for evaluation of Crohn's disease. Two radiologists reviewed only contrast-enhanced T1-weighted images in consensus on the first session. Whole images including unenhanced (steady-state free precession, single-shot fast spin-echo (HASTE), fat-suppressed T2-weighted) and contrast-enhanced T1-weighted sequences were reviewed in consensus during the second session with a 1 month interval, which was used as a reference standard. The readers evaluated the presence or absence of disease in 10 bowel segments in each patient. For the abnormal bowel segments, the readers then evaluated for active versus inactive disease and for the presence or absence of abscess. Sensitivity, specificity, and overall accuracy were calculated for detecting active inflammation. Results: There were 53/250 bowel segments with active inflammation using the reference standard imaging method. The sensitivity, specificity, and accuracy for diagnosing active inflammation using contrast-enhanced images alone were 83.3%, 86.9%, and 84.9%. In five of the false-positive cases of detecting abscess from contrast-enhanced imaging alone, absence of abscesses was confirmed on the non-fat-suppressed HASTE images. Conclusion: The number of MRE sequences in paediatric Crohn's patients can be decreased while maintaining diagnostic accuracy using contrast-enhanced T1 and non-fat-suppressed HASTE images

  11. Adaptive robust pole-placement control of 4-leg voltage-source inverters for standalone photovoltaic systems: Considering digital delays

    International Nuclear Information System (INIS)

    Nasiri, Reza; Radan, Ahmad

    2011-01-01

    Three leg inverters for photovoltaic systems have a lot of disadvantages, especially when the load is unbalanced. These disadvantages are for example, small utilization of the DC link voltage, the dependency of the modulation factor of the load current and the superposition of a DC component with the output AC voltage. A solution for these problems is the 4-leg inverter. Most papers dealing with 4-leg inverters ignore the effect of digital delays in control loop and suggest classic controllers, such as PI controller. However, the transient performance of the system does not become adjustable by applying classic control techniques. Additionally, adaptive control techniques have not yet been discussed for 4-leg inverters. This paper proposes the pole-placement control strategy via state feedback with integral state, which is a modern control technique, to control the system. Consequently, resulted system becomes highly robust. In addition, it suggests a Self-Tuner Regulator to guarantee the adaptive performance of the final system. Moreover, it proposes a novel model, considering digital delays, for 4-leg inverters. Simulation results show that transient performance of the system becomes accurately adjustable and the 4-leg inverter generates balanced voltage, with sinusoidal waveform, in spite of the presence of RL time variant loads.

  12. FAA aircraft certification human factors and operations checklist for standalone GPS receivers (TSO C129 Class A)

    Science.gov (United States)

    1995-04-01

    This document is a checklist designed to assist Federal Aviation Administration(FAA) certification personnel and global : positioning system (GPS) receiver manufacturers in the evaluation of the pilot-system interface characteristlcs of GPS : recieve...

  13. System dynamic model and charging control of lead-acid battery for stand-alone solar PV system

    KAUST Repository

    Huang, B.J.; Hsu, P.C.; Wu, M.S.; Ho, P.Y.

    2010-01-01

    . This will reduce the storage energy capacity and reduce the service time in electricity supply. The design of charging control system however requires a good understanding of the system dynamic behaviour of the battery first. In the present study, a first

  14. Optimizing the solar array of stand-alone photovoltaic energy systems as a function of time and load profiles

    Science.gov (United States)

    Abou-Hussein, M. S.; El-Maghraby, M. H.; Groumpos, P. P.; El-Geldawy, F. A.; El-Tamaly, H. H.

    This paper presents a proposed novel technique in which an accurate optimum design of the solar array (SCA) can be attained. It depends on an hour-by-hour approach with different daily load profiles. A generalized mathematical formula has been developed for sizing of the solar array given the geographical and one year's insolation data for a particular site in Egypt. This approach can reduce the required size compared to other methods using the same tilt angle.

  15. Modeling and simulation of stand-alone hybrid power system with fuzzy MPPT for remote load application

    Directory of Open Access Journals (Sweden)

    Bogaraj T.

    2015-09-01

    Full Text Available Many parts of remote locations in the world are not electrified even in this Advanced Technology Era. To provide electricity in such remote places renewable hybrid energy systems are very much suitable. In this paper PV/Wind/Battery Hybrid Power System (HPS is considered to provide an economical and sustainable power to a remote load. HPS can supply the maximum power to the load at a particular operating point which is generally called as Maximum Power Point (MPP. Fuzzy Logic based MPPT (FLMPPT control method has been implemented for both Solar and Wind Power Systems. FLMPPT control technique is implemented to generate the optimal reference voltage for the first stage of DC-DC Boost converter in both the PV and Wind energy system. The HPS is tested with variable solar irradiation, temperature, and wind speed. The FLMPPT method is compared with P&O MPPT method. The proposed method provides a good maximum power operation of the hybrid system at all operating conditions. In order to combine both sources, the DC bus voltage is made constant by employing PI Controllers for the second stage of DC-DC Buck-Boost converter in both Solar and Wind Power Systems. Battery Bank is used to store excess power from Renewable Energy Sources (RES and to provide continuous power to load when the RES power is less than load power. A SPWM inverter is designed to convert DC power into AC to supply three phase load. An LC filter is also used at the output of inverter to get sinusoidal current from the PWM inverter. The entire system was modeled and simulated in Matlab/Simulink Environment. The results presented show the validation of the HPS design.

  16. Planning tool for least cost system design based on the operating experience of fifty stand-alone photovoltaic hybrid systems

    Energy Technology Data Exchange (ETDEWEB)

    Bopp, G.; Neufeld, R.; Preiser, K.; Puls, H.-G.; Sauer, D.U.; Senft, S.; Schulz, M. [Fraunhofer Inst. for Solar Energy Systems ISE, Freiburg (Germany)

    2001-07-01

    The Fraunhofer Institute for Solar Energy (ISE) conducted a project involving the design and installation of grid-independent photovoltaic systems with battery storage to 30 remote lodges, mountain huts, farms and private houses. More than half the participating dwellings belonged to the German Alpine Club and are used only for summer months. The photovoltaic systems ranged from lighting for unattended huts and larger systems for lodges with permanent staff and an electricity demand in the order of 0.1 to 40 kWh per day. The objective of the project was to determine the amount of maintenance work that is required to keep the systems working reliably. The Institute prepared inspection manuals and carried out some sample inspections. Other inspections were carried out by the independent operator. With the information entered into the inspection manuals, Fraunhofer ISE analyzed the causes of faults and prepared statistics on interruptions to operations. The average probability of breakdowns could then be determined along with the requirements for optimizing individual components and the entire system. Besides the solar generator, most components of a photovoltaic system with battery storage require repairs, post-installation improvements, regular maintenance or replacement of batteries at intervals of 5 to 10 years. At the end of two years of regular maintenance, the fault rates were reduced from 3 to 1. The Institute also developed the Technical and Least Cost Optimisation (TALCO) tool to calculate the lifetime costs of remote area power supply systems. TALCO describes the electrical characteristics of various components under operating conditions. All economic factors linked to the components are considered. The optimisation algorithm presents the minimum lifetime costs for a given energy demand at specific locations under given boundary conditions. Analytical results showed that PV-hybrid systems are the most cost effective solution for most system applications with less than 15000 kWh per year annual energy consumption. 9 refs., 7 tabs., 7 figs.

  17. Study of a thermoelectric system equipped with a maximum power point tracker for stand-alone electric generation.

    Science.gov (United States)

    Favarel, C.; Champier, D.; Bédécarrats, J. P.; Kousksou, T.; Strub, F.

    2012-06-01

    According to the International Energy Agency, 1.4 billion people are without electricity in the poorest countries and 2.5 billion people rely on biomass to meet their energy needs for cooking in developing countries. The use of cooking stoves equipped with small thermoelectric generator to provide electricity for basic needs (LED, cell phone and radio charging device) is probably a solution for houses far from the power grid. The cost of connecting every house with a landline is a lot higher than dropping thermoelectric generator in each house. Thermoelectric generators have very low efficiency but for isolated houses, they might become really competitive. Our laboratory works in collaboration with plane`te-bois (a non governmental organization) which has developed energy-efficient multifunction (cooking and hot water) stoves based on traditional stoves designs. A prototype of a thermoelectric generator (Bismuth Telluride) has been designed to convert a small part of the energy heating the sanitary water into electricity. This generator can produce up to 10 watts on an adapted load. Storing this energy in a battery is necessary as the cooking stove only works a few hours each day. As the working point of the stove varies a lot during the use it is also necessary to regulate the electrical power. An electric DC DC converter has been developed with a maximum power point tracker (MPPT) in order to have a good efficiency of the electronic part of the thermoelectric generator. The theoretical efficiency of the MMPT converter is discussed. First results obtained with a hot gas generator simulating the exhaust of the combustion chamber of a cooking stove are presented in the paper.

  18. SKI Project-90. Geosphere calculations using CRYSTAL: Stand-alone and CALIBRE-CRYSTAL-biosphere integrated results

    International Nuclear Information System (INIS)

    Worgan, K.; Shaw, W.

    1992-02-01

    In Project-90, the far-field transport of nuclides is assumed to take place in a 200 m long section of rock mass, which starts at the outer boundary of the near-field and ends in a fracture zone. The nuclides are eventually discharged to the biosphere. This document provides an overview of the results obtained with the far-field model CRYSTAL developed by Intera Environmental Division for the Swedish Nuclear Power Inspectorate (SKI). It reports on the results of a series of calculation that have been performed within the SKIs Project-90, and provides some indication of the key parameters for the far field. A more thorough discussion of the implications for performance assessment is given in the Project-90 reports. (au)

  19. A new technique based on Artificial Bee Colony Algorithm for optimal sizing of stand-alone photovoltaic system

    OpenAIRE

    Mohamed, Ahmed F.; Elarini, Mahdi M.; Othman, Ahmed M.

    2013-01-01

    One of the most recent optimization techniques applied to the optimal design of photovoltaic system to supply an isolated load demand is the Artificial Bee Colony Algorithm (ABC). The proposed methodology is applied to optimize the cost of the PV system including photovoltaic, a battery bank, a battery charger controller, and inverter. Two objective functions are proposed: the first one is the PV module output power which is to be maximized and the second one is the life cycle cost (LCC) whic...

  20. Real-Time Detection of Tsunami Ionospheric Disturbances with a Stand-Alone GNSS Receiver: A Preliminary Feasibility Demonstration

    Science.gov (United States)

    Savastano, Giorgio; Komjathy, Attila; Verkhoglyadova, Olga; Mazzoni, Augusto; Crespi, Mattia; Wei, Yong; Mannucci, Anthony J.

    2017-04-01

    It is well known that tsunamis can produce gravity waves that propagate up to the ionosphere generating disturbed electron densities in the E and F regions. These ionospheric disturbances can be studied in detail using ionospheric total electron content (TEC) measurements collected by continuously operating ground-based receivers from the Global Navigation Satellite Systems (GNSS). Here, we present results using a new approach, named VARION (Variometric Approach for Real-Time Ionosphere Observation), and estimate slant TEC (sTEC) variations in a real-time scenario. Using the VARION algorithm we compute TEC variations at 56 GPS receivers in Hawaii as induced by the 2012 Haida Gwaii tsunami event. We observe TEC perturbations with amplitudes of up to 0.25 TEC units and traveling ionospheric perturbations (TIDs) moving away from the earthquake epicenter at an approximate speed of 316 m/s. We perform a wavelet analysis to analyze localized variations of power in the TEC time series and we find perturbation periods consistent with a tsunami typical deep ocean period. Finally, we present comparisons with the real-time tsunami MOST (Method of Splitting Tsunami) model produced by the NOAA Center for Tsunami Research and we observe variations in TEC that correlate in time and space with the tsunami waves.