Gotowe bibliografie tematyczne / Low latitude current systems

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Gotowa bibliografia na temat „Low latitude current systems”

Autor: Grafiati
Data publikacji: 6 września 2023

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Artykuły w czasopismach na temat "Low latitude current systems"

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Tinsley, B. A., R. Rohrbaugh, H. Rassoul, Y. Sahai, N. R. Teixeira i D. Slater. "Low-latitude aurorae and storm time current systems". Journal of Geophysical Research 91, A10 (1986): 11257. http://dx.doi.org/10.1029/ja091ia10p11257.

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Saka, O., J. S. Kim i D. J. Knecht. "Ionospheric equivalent current systems of low-latitude Pc3 pulsations". Planetary and Space Science 36, nr 7 (lipiec 1988): 641–53. http://dx.doi.org/10.1016/0032-0633(88)90112-2.

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Grafe, A., P. A. Bespalov, V. Y. Trakhtengerts i A. G. Demekhov. "Afternoon mid-latitude current system and low-latitude geomagnetic field asymmetry during geomagnetic storms". Annales Geophysicae 15, nr 12 (31.12.1997): 1537–47. http://dx.doi.org/10.1007/s00585-997-1537-5.

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Abstract. For four geomagnetic storms of middle intensity the relationship between the low-latitude magnetic field asymmetry using ASY indices and the intensity of the auroral eastward and westward electrojet was considered. It was asked whether there exists a connection between ASY and the eastward electrojet. To answer this question equivalent current systems were estimated in mid-latitudes. It was found that the observations obviously show no correlative relationship between the low-latitude magnetic-field asymmetry and the eastward electrojet, whereas one exists between ASY and the westward electrojet. To explain the generally accepted common three-dimensional current system between the partial ring current and the eastward electrojet, a condensor model of the three-dimensional current system was developed. It could be shown that the short periodic variations of the partial ring current are shielded by the condensor and cannot influence the eastward-electrojet current.
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Liu, Ping, Chun Ming Liu i Lian Guang Liu. "Variation Characteristics of Geoelectric Field in Mid-to-Low Latitude Area during Geomagnetic Storms". Advanced Materials Research 1008-1009 (sierpień 2014): 524–29. http://dx.doi.org/10.4028/www.scientific.net/amr.1008-1009.524.

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Large geoelectric field generated in the ground during severe space weather events are sources of geomagnetically induced currents (GICs), which flow in power systems potentially causing damage to system component or failure of the system. In this paper, based on the H and D components of the recent geomagnetic storm data measured at 10 mid-to-low latitude geomagnetic observatories, we analyzed the variation characteristics of the amplitude of north-south and east-west geoelectric components with geographic latitudes. Furthermore, we discussed the possibilities of GIC problem occurrence in transmission lines in different directions at different latitude in China. The result shows that transmission lines in east-west direction at higher latitude are more susceptible to space weather hazard. And it will contribute to the assessment of geomagnetic hazard to power systems and the control of GIC in the current and future power grids in China.
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Barkhatov, N. A., S. E. Revunov, O. T. Cherney, M. V. Mukhina i Zh V. Smirnova. "Neural networks technique for detecting current systems while main phase of geomagnetic storm". E3S Web of Conferences 220 (2020): 01091. http://dx.doi.org/10.1051/e3sconf/202022001091.

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The study demonstrated the technology for searching nonlinear correlations between the intensity indices of auroral electric jets (AU, AL) and ring current intensity indices (SYM, ASY). The well-known connection of the western electrojet with the asymmetric part of the ring current and the eastern electrodett with the symmetric is confirmed. The technology of artificial neural networks was chosen as the main method. Thus, the relationship of magnetic disturbances in the auroral region and magnetic disturbances at middle and low latitudes in the main phase of a geomagnetic storm is investigated. The characteristic lead times in the development of mid-latitude magnetospheric processes relative to polar are determined. An acceptable neural network recovery of auroral electrojet intensity indices from ring current index data is demonstrated.
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Lovati, Giulia, Paola De Michelis, Giuseppe Consolini i Francesco Berrilli. "Pressure-Gradient Current at High Latitude from Swarm Measurements". Remote Sensing 14, nr 6 (15.03.2022): 1428. http://dx.doi.org/10.3390/rs14061428.

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The pressure-gradient current is among the weaker ionospheric current systems arising from plasma pressure variations. It is also called diamagnetic current because it produces a magnetic field which is oriented oppositely to the ambient magnetic field, causing its reduction. The magnetic reduction can be revealed in measurements made by low-Earth orbiting satellites flying close to ionospheric plasma regions where rapid changes in density occur. Using geomagnetic field, plasma density and electron temperature measurements recorded on board ESA Swarm A satellite from April 2014 to March 2018, we reconstruct the flow patterns of the pressure-gradient current at high-latitude ionosphere in both hemispheres, and investigate their dependence on magnetic local time, geomagnetic activity, season and solar forcing drivers. Although being small in amplitude these currents appear to be a ubiquitous phenomenon at ionospheric high latitudes characterized by well defined flow patterns, which can cause artifacts in the main field models. Our findings can be used to correct magnetic field measurements for diamagnetic current effect, to improve modern magnetic field models, as well as to understand the impact of ionospheric irregularities on ionospheric dynamics at small-scale sizes of a few tens of kilometers.
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Belenkaya, E. S., I. I. Alexeev i C. R. Clauer. "Magnetic field of the transition current system: dawn-dusk asymmetry". Annales Geophysicae 25, nr 8 (29.08.2007): 1899–911. http://dx.doi.org/10.5194/angeo-25-1899-2007.

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Abstract. In this paper we consider the interactions of coronal mass ejections (CMEs) with the Earth's magnetosphere for the specific case in which there is a sharp increase in the dynamic pressure (interplanetary shock) that is associated with a simultaneous northward turning of the interplanetary magnetic field (IMF) from the near horizontal direction. Previously, we have shown that under such circumstances, the so-called transition current systems arise. These temporary high-latitude current systems create a low-latitude asymmetric magnetic field on the ground with a large northward field enhancement on the nightside and little or no field increase near local noon. Here we investigate the dawn-dusk asymmetry of the low-latitude on-ground magnetic field of the transition current system caused by the IMF. Analysis of the Region 1 current circuit for northward IMF shows a change in its shape controlled by different IMF components. Due to this geometrical effect, the maximum and minimum magnetic field disturbances appear to be shifted. The obtained results supplement and define more precisely the locations of the magnetic disturbance extrema retrieved recently by Clauer et al. (2001). The results of this study are compared with the available observations. A good accordance is demonstrated.
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Yang, Lucy, Nyree Zerega, Anastasia Montgomery i Daniel E. Horton. "Potential of breadfruit cultivation to contribute to climate-resilient low latitude food systems". PLOS Climate 1, nr 8 (17.08.2022): e0000062. http://dx.doi.org/10.1371/journal.pclm.0000062.

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The number of people in food crisis around the world is increasing, exacerbated by COVID-19, conflict, and climate change. Major crop yields are projected to decrease in low-latitude regions, making tropical and sub-tropical food systems particularly vulnerable. Increased cultivation of breadfruit (Artocarpus altilis), a neglected and underutilized species (NUS), has the potential to enhance climate resilience and overall sustainability of low-latitude agricultural systems. To better understand breadfruit’s cultivation suitability and geographic range in current and future climates, we use breadfruit presence data collected from previous studies and a global citizen science database, and a selection of bioclimactic variables, to build an ensemble of 6 species distribution models that delineate the current climatically viable breadfruit range. We then assess the climatically viable future breadfruit range (2061–2080) under stabilization and high emission scenarios using an ensemble of 8 global circulation model (GCM) projections. The area of suitable breadfruit range within the global tropics and subtropics is projected to decrease ~4.4% in the stabilization scenario and ~4.5% in the high emission scenario. In Southeast Asia and the Pacific Islands, yield quality and consistency show minimal decreases under the high emission scenario, with increases in total suitable area under both. In contrast, in Latin America and the Caribbean, the current suitable breadfruit range is projected to contract ~10.1–11.5% (stabilization-high emission). Present and future model suitability outputs suggest opportunities to successfully expand breadfruit cultivation over the next decades in sub-Saharan Africa, where food insecurity is coincidentally high. However, in all regions, high emission scenario conditions reduce the overall consistency and quality of breadfruit yields compared to the stabilization scenario. Our results have the potential to inform global food security adaptation planning, highlighting breadfruit as an ideal NUS to incorporate in food security adaptation strategies.
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Clilverd, Mark A., Craig J. Rodger, Sarah Dietrich, Tero Raita, Thomas Ulich, Ellen Clarke, Alan W. P. Thomson i Andrew J. Kavanagh. "High-latitude geomagnetically induced current events observed on very low frequency radio wave receiver systems". Radio Science 45, nr 2 (kwiecień 2010): n/a. http://dx.doi.org/10.1029/2009rs004215.

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Spall, Michael A., i David Nieves. "Wind-Forced Variability of the Remote Meridional Overturning Circulation". Journal of Physical Oceanography 50, nr 2 (luty 2020): 455–69. http://dx.doi.org/10.1175/jpo-d-19-0190.1.

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AbstractThe mechanisms by which time-dependent wind stress anomalies at midlatitudes can force variability in the meridional overturning circulation at low latitudes are explored. It is shown that winds are effective at forcing remote variability in the overturning circulation when forcing periods are near the midlatitude baroclinic Rossby wave basin-crossing time. Remote overturning is required by an imbalance in the midlatitude mass storage and release resulting from the dependence of the Rossby wave phase speed on latitude. A heuristic theory is developed that predicts the strength and frequency dependence of the remote overturning well when compared to a two-layer numerical model. The theory indicates that the variable overturning strength, relative to the anomalous Ekman transport, depends primarily on the ratio of the meridional spatial scale of the anomalous wind stress curl to its latitude. For strongly forced systems, a mean deep western boundary current can also significantly enhance the overturning variability at all latitudes. For sufficiently large thermocline displacements, the deep western boundary current alternates between interior and near-boundary pathways in response to fluctuations in the wind, leading to large anomalies in the volume of North Atlantic Deep Water stored at midlatitudes and in the downstream deep western boundary current transport.
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Rozprawy doktorskie na temat "Low latitude current systems"

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Tsunomura, Satoru. "On the Contribution of Global Scale Polar-originating Ionospheric Current Systems to Geomagnetic Disturbances in Middle and Low Latitudes". 京都大学 (Kyoto University), 1999. http://hdl.handle.net/2433/182006.

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Gammon, Tammy Lea. "Improved arcing-fault current models for low-voltage power systems (<1kV)". Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/15675.

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Yokoyama, Yoshihiro. "Characteristics of the mesoscale field-aligned currents in the dusk sector of the auroral oval based on data from the Swarm satellites". Kyoto University, 2021. http://hdl.handle.net/2433/261602.

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Arbetter, Barry Steven. "DC-DC converter utilizing hysteretic current-mode control for low-voltage microprocessor systems with power management". Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3219222.

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Miwa, Hidekazu. "High-Efficiency Low-Voltage High-Current Power Stage Design Considerations for Fuel Cell Power Conditioning Systems". Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/42519.

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Fuel cells typically produce low-voltage high-current output because their individual cell voltage is low, and it is nontrivial to balance for a high-voltage stack. In addition, the output voltage of fuel cells varies depending on load conditions. Due to the variable low voltage output, the energy produced by fuel cells typically requires power conditioning systems to transform the unregulated source energy into more useful energy format. When evaluating power conditioning systems, efficiency and reliability are critical. The power conditioning systems should be efficient in order to prevent excess waste of energy. Since loss is dissipated as heat, efficiency directly affects system reliability as well. High temperatures negatively affect system reliability. Components are much more likely to fail at high temperatures. In order to obtain excellent efficiency and system reliability, low-voltage high-current power conditioning systems should be carefully designed. Low-voltage high-current systems require carefully designed PCB layouts and bus bars. The bus bar and PCB trace lengths should be minimized. Therefore, each needs to be designed with the other in mind. Excessive PCB and bus bar lengths can introduce parasitic inductances and resistances which are detrimental to system performance. In addition, thermal management is critical. High power systems must have sufficient cooling in order to maintain reliable operation. Many sources of loss exist for converters. For low-voltage high-current systems, conduction loss and switching loss may be significant. Other potential non-trivial sources of loss include magnetic losses, copper losses, contact and termination losses, skin effect losses, snubber losses, capacitor equivalent series resistance (ESR) losses, and body diode related losses. Many of the losses can be avoided by carefully designing the system. Therefore, in order to optimize efficiency, the designer should be aware of which components contribute significant amounts of loss. Loss analysis may be performed in order to determine the various sources of loss. The system efficiency can be improved by optimizing components that contribute the most loss. This thesis surveys some potential topologies suitable for low-voltage high-current systems. One low-voltage high-current system in particular is analyzed in detail. The system is called the V6, which consists of six phase legs, and is arranged as a three full-bridge phase-shift modulated converter to step-up voltage for distributed generation applications. The V6 converter has current handling requirements of up to 120A. Basic operation and performance is analyzed for the V6 converter. The loss within the V6 converter is modeled and efficiency is estimated. Calculations are compared with experimental results. Efficiency improvement through parasitic loss reduction is proposed by analyzing the losses of the V6 converter. Substantial power savings are confirmed with prototypes and experimental results. Loss analysis is utilized in order to obtain high efficiency with the V6 converter. Considerations for greater current levels of up to 400A are also discussed. The greater current handling requirements create additional system issues. When considering such high current levels, parallel devices or modules are required. Power stage design, layout, and bus bar issues due to the high current nature of the system are discussed.
Master of Science
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Ziegler, Silvio. "New current sensing solutions for low-cost high-power-density digitally controlled power converters". University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0077.

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[Truncated abstract] This thesis studies current sensing techniques that are designed to meet the requirements for the next generation of power converters. Power converters are often standardised, so that they can be replaced with a model from another manufacturer without an expensive system redesign. For this reason, the power converter market is highly competitive and relies on cutting-edge technology, which increases power conversion efficiency and power density. High power density and conversion efficiency reduce the system cost, and thus make the power converter more attractive to the customer. Current sensing is a vital task in power converters, where the current information is required for monitoring and control purposes. In order to achieve the above-mentioned goals, existing current sensing techniques have to be improved in terms of cost, power loss and size. Simultaneously, current information needs to be increasingly available in digital form to enable digital control, and to allow the digital transmission of the current information to a centralised monitoring and control unit. All this requires the output signal of a particular current sensing technique to be acquired by an analogue-to-digital converter, and thus the output voltage of the current sensor has to be sufficiently large. This thesis thoroughly reviews contemporary current sensing techniques and identifies suitable techniques that have the potential to meet the performance requirements of the next-generation of power converters. After the review chapter, three novel current sensing techniques are proposed and investigated: 1) The usefulness of the resistive voltage drop across a copper trace, which carries the current to be measured, to detect electrical current is evaluated. Simulations and experiments confirm that this inherently lossless technique can measure high currents at reasonable measurement bandwidth, good accuracy and low cost if the sense wires are connected properly. 2) Based on the mutual inductance theory found during the investigation of the copper trace current sense method, a modification of the well-known lossless inductor current sense method is proposed and analysed. This modification involves the use of a coupled sense winding that significantly improves the frequency response. Hence, it becomes possible to accurately monitor the output current of a power converter with the benefits of being lossless, exhibiting good sensitivity and having small size. 3) A transformer based DC current sense method is developed especially for digitally controlled power converters. This method provides high accuracy, large bandwidth, electrical isolation and very low thermal drift. Overall, it achieves better performance than many contemporary available Hall Effect sensors. At the same time, the cost of this current sensor is significantly lower than that of Hall Effect current sensors. A patent application has been submitted. .... The current sensing techniques have been studied by theory, hardware experiments and simulations. In addition, the suitability of the detection techniques for mass production has been considered in order to access the ability to provide systems at low-cost.
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Mendoza, Arenas Juan José. "Spin and energy transport in boundary-driven low-dimensional open quantum systems". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:44b89c4d-e9eb-4136-a540-c80bcabeb6f6.

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In spite of being the subject of intense research, several key but complex questions on the nonequilibrium physics of correlated quantum systems remain controversial. For example, the nature of particle and energy transport in different interacting regimes, the relevance of integrability and the impact of environmental coupling are still under active debate. These problems can now be approached numerically, due to the development of powerful algorithms which allow the efficient simulation of the dynamics of correlated systems. In the present thesis we study numerically and analytically the transport properties of low-dimensional quantum systems. In particular, we consider the steady-state spin and energy conduction through XXZ boundary-driven spin-1/2 chains. In the first part, we analyse the transport through chains with only coherent processes in the bulk. For spin transport induced by a magnetisation imbalance between the boundaries, previously identified ballistic, diffusive and negative differential conductivity regimes are reproduced. We provide a comprehensive explanation of the latter. The energy conduction induced by this driving scheme features the same properties as spin transport. For thermally-driven chains, we discuss the nature of energy transport and the emergence of local thermal states when the integrability of the Hamiltonian is broken. In the second part of the thesis we analyse the effect of bulk incoherent effects on the transport properties previously discussed. First we find that for weak particle-particle interactions, pure dephasing degrades spin and energy conduction. In contrast, for strong interactions dephasing induces a significant transport enhancement. We identify the underlying mechanism and discuss its generality. Finally, motivated by the lattice structure of several organic conductors, we study the interplay between coherent and incoherent processes in systems of weakly-coupled chains. We find an enhancement effect due to incoherent interchain hopping, stronger than that by dephasing, which increases with the chain length and relates to superdiffusive transport.
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MOSCA, CARMELO. "Methodologies for Frequency Stability Assessment in Low Inertia Power Systems". Doctoral thesis, Politecnico di Torino, 2021. http://hdl.handle.net/11583/2895393.

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Heim, Marcus Edwin Allan. "ANALYSIS OF MOS CURRENT MODE LOGIC (MCML) AND IMPLEMENTATION OF MCML STANDARD CELL LIBRARY FOR LOW-NOISE DIGITAL CIRCUIT DESIGN". DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1422.

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MOS current mode logic (MCML) offers low noise digital circuits that reduce noise that can cripple analog components in mixed-signal integrated circuits, when compared to CMOS digital circuits. An MCML standard cell library was developed for the Cadence Virtuoso Integrated Circuit (IC) design software that gives IC designers the ability to design complex, low noise digital circuits for use in mixed-signal and noise sensitive systems at a high level of abstraction, allowing them to get superior products to market faster than competitors. The MCML standard cell library developed and presented here allows for fast development of mixed signal circuits by providing quiet digital building block gates that reduce the simultaneous switching noise (SSN) by an order of magnitude over conventional CMOS based designs [3]. This thesis project developed the following digital gates in MCML as a standard cell library for general-purpose low noise and very low noise applications: inverter, buffer, NAND, AND, NOR, OR, XOR, NXOR, 2:1 MUX, CMOS to MCML, MCML to CMOS, and double edge triggered flip-flop (DETFF).
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Geury, Thomas. "Smart matrix converter-based grid-connected photovoltaic system for mitigating current and voltage-related power quality issues on the low-voltage grid". Doctoral thesis, Universite Libre de Bruxelles, 2017. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/243967.

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The increasing penetration of distributed energy resources, in particular Photovoltaic (PV) production units, and the ever-growing use of power electronics-based equipment has led to specific concern about Power Quality (PQ) in the Low-Voltage (LV) grid. These include high- and low-order current harmonics as well as voltage distortion at the point of common coupling. Solutions to overcome these issues, meeting international grid codes, are being proposed in the context of smart energy management schemes.This work proposes a novel three-phase topology for a PV system with enhanced PQ mitigation functionality, tackling the corresponding control challenges.First, a single-stage current-source inverter PV system with active filtering capability is preferred to the more common two-stage voltage-source inverter topology with additional voltage-step-up converter. The system also guarantees a nearly unitary displacement power factor in the connection to the grid and allows for Maximum Power Point Tracking (MPPT) with direct control of the PV array power. The grid-synchronised dq-axis grid current references are generated for the mitigation of nonlinear load low-order current harmonics, without the need for additional measurements. Active damping is used to minimise grid-side filter losses and reduce high-order harmonics resulting from the converter switching.Results on a 500W laboratory prototype confirm that active damping reduces the switching harmonics in the grid currents and active filtering properly mitigates the low-order current harmonics. The MPPT algorithm works effectively for various irradiance variations. Second, a PV system with a novel Indirect Matrix Converter (IMC)-based unified power quality conditioner topology is developed for enhanced current and voltage compensation capability, with compactness and reliability advantages. PQ issues such as current harmonics, and voltage sags, swells, undervoltage and overvoltage are mitigated by the shunt and series converters, respectively.The more common Space Vector Modulation (SVM) method used in IMCs is developed for this specific topology. In particular, a new shunt converter modulation method is proposed to additionally control the PV array current with zero switching vectors, resulting in a specific switching sequence.A direct sliding mode control method is also studied separately for the shunt and series converters, so that the zero-vector modulation method of the shunt converter can be used, with no sensitive synchronisation of the switching signals; this contrasts with the SVM method. A new dc link voltage modulation method with 12 voltage zones, instead of 6, is proposed to help overcome the limitation in the choice of shunt converter switching vectors due to the positive dc link voltage constraint.Results are obtained for the direct method on a 1 kW laboratory prototype with optimised IMC dc link connection and alternative shunt converter switching transitions to guarantee a positive dc link voltage. Current and voltage compensation capabilities are confirmed by tests in various operating conditions.
Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
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Książki na temat "Low latitude current systems"

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Smith, Rasler W. Low latitude ionospheric effects on radiowave propagation. Monterey, Calif: Naval Postgraduate School, 1998.

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C, Guerrini Nicola, red. Low-voltage low-power CMOS current conveyors. Boston: Kluwer Academic Publishers, 2003.

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J, Plassche Rudy, i Sansen Willy M. C, red. Analog Circuit Design: Low-Noise, Low-Power, Low-Voltage; Mixed-Mode Design with CAD Tools; Voltage, Current and Time References. Boston, MA: Springer US, 1996.

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Institute Of Electrical and Electronics Engineers. IEEE recommended practice on surge voltages in low-voltage AC power circuits. New York: IEEE, 1991.

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IEEE Power Engineering Society. Switchgear Committee., red. IEEE standard for low-voltage AC power circuit breakers used in enclosures. New York, NY, USA: Institute of Electrical and Electronics Engineers, 1991.

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Stanton, Bonita. Physics and technology of high current discharges in dense gas media and flows. Hauppauge, N.Y: Nova Science Publishers, 2009.

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Prohorov, Viktor. Semiconductor converters of electrical energy. ru: INFRA-M Academic Publishing LLC., 2020. http://dx.doi.org/10.12737/1019082.

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The textbook considers the need, principles and methods of mutual conversion of parameters of electric energy at DC and AC for stationary and Autonomous objects. Features of operation of power electronics elements in specific conditions of their continuous high-frequency switching are described. Low-current control systems that provide the necessary logic for the operation of Executive power devices of converters are considered. A large number of specific practical electrical diagrams of electric energy converters are given. It is intended for students studying in the direction of 13.03.02 "electric power and electrical engineering". It can be useful for graduate students and specialists involved in the development and operation of electric power converters.
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Zagirnyak, Mykhaylo V. Nonactive Current Components Compensation of Low-Voltage Power Supply Systems. Nova Science Publishers, Incorporated, 2020.

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Zagirnyak, Mykhaylo V. Nonactive Current Components Compensation of Low-Voltage Power Supply Systems. Nova Science Publishers, Incorporated, 2020.

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Trends in Low-Power Electronics (Current Topics in Electronics and Systems, Vol 2). World Scientific Pub Co Inc, 1994.

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Części książek na temat "Low latitude current systems"

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Baumjohann, W., i E. Friis-Christensen. "Dayside High-Latitude Ionospheric Current Systems". W The Polar Cusp, 223–34. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5295-9_16.

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Rajput, S. S., i S. S. Jamuar. "High Current, Low Voltage Current Mirrors and Applications". W VLSI: Systems on a Chip, 47–60. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/978-0-387-35498-9_5.

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Clauer, C. Robert. "Solar Wind Control of High Latitude Dayside Current Systems". W Physical Signatures of Magnetospheric Boundary Layer Processes, 29–41. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1052-5_2.

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Rana, Charu, Neelofer Afzal, Dinesh Prasad i Anu. "Low-Voltage Low-Power FGMOS-Based Current Conveyor III". W Advances in Power Systems and Energy Management, 673–81. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-4394-9_66.

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Hala, J., J. Dian, O. Prasil, M. Vacha i K. Vacek. "High Resolved Low Temperature Spectroscopy of Photosynthetic Systems". W Current Research in Photosynthesis, 1165–68. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-0511-5_271.

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Anil Kumar, P., S. Tamil i Nikhil Raj. "Design of Low Voltage Improved Current Mirror". W Lecture Notes in Networks and Systems, 555–61. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-8512-5_58.

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Gálvez-Durand, Federico. "Low-voltage current-mode analogue continuous-time filters". W VLSI: Integrated Systems on Silicon, 139–50. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-0-387-35311-1_12.

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Vidhate, Ashok D., i Shruti Suman. "A Novel Low-Voltage High-Performance Current Mirror". W Lecture Notes in Networks and Systems, 317–27. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-0980-0_30.

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Kavitha, D., P. Naveen Kumar i K. Praveena. "Comparison of VTEC Due to IRI-2016 Model and IRNSS over Low Latitude Region". W Learning and Analytics in Intelligent Systems, 320–26. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-24318-0_39.

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Chwieduk, Dorota. "Achievement of Low-Energy Buildings in High-Latitude Countries Through Passive Solar Systems". W Renewable Energy and Sustainable Buildings, 955–61. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-18488-9_80.

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Streszczenia konferencji na temat "Low latitude current systems"

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Olszewski, Pawel. "The Possibility of Using the Ground as a Seasonal Heat Storage: The Numerical Study". W ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56185.

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Humankind can effectively utilize only part of the solar energy reaching a surface of the Earth. It is due to the low density of the solar radiation and its unfavorable distribution. The majority of solar energy falls to the low latitude countries, where space-heating requirements are marginal. In these countries the solar heat is used for preparing water for washing or cleaning purposes, and this process works in one, or — maximum — a few daily cycles. In countries located at higher latitudes, where space heating is necessary in cold months, the current solar energy is insufficient to meet the space heating demand. The heat storage in deep layer of the ground is the one of possible way for solution of this problem. During the heating season, energy storage is discharged supplying the heat pomp cooperating with domestic heating system and during the summer months the storage can be charged by fluid heated in solar collectors. The main aim of presented research was analysis of using the ground layer as a heat storage system in the countries located in higher latitudes. The first variable taken into consideration was the output temperature of water leaving the solar collectors. The temperature distribution in the ground depends on the inlet water temperature, primary heated in the solar collectors, and forced into vertical boreholes. The temperature field in the ground was calculated using the duFort-Frankel finite-difference numerical method. A numerical code for 3D time dependent storage simulation has been created. The next step of analysis was calculation of waters’ temperature at the borehole output during cold months when the ground storage is discharged. This water works as a low-temperature reservoir of the heat pomp supplying the dwelling heating system. The solution of the problem is focused on an optimization of all parameters for the most efficient utilization of energy stored in the ground. The numerical genetic algorithms are scheduled to use to achieve this target.
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Arenas, Javier, Esther Sardon, Ana Sainz, Begona Ochoa i Sergio Magdaleno. "Low latitude ionospheric effects on SBAS systems". W 2015 1st URSI Atlantic Radio Science Conference (URSI AT-RASC). IEEE, 2015. http://dx.doi.org/10.1109/ursi-at-rasc.2015.7303133.

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Sarsam, Saad I. "Implementation of Surveying Techniques in the Route Selection for Baghdad Metro Tube". W INTERNATIONAL CONFERENCE ON ARCHITECTURAL AND CIVIL ENGINEERING 2020. Cihan University-Erbil, 2021. http://dx.doi.org/10.24086/aces2020/paper.176.

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Transportation systems play a central role in a sustainable society by providing mobility for people, goods, and services. Significant sustainability benefits are being derived through the improvements in transportation network efficiency, use of alternative modes and multimodality, integration of sustainable design, better integration of land use and transportation systems. Sustainable transportation system usually refers to any means of transportation which has low impact on the environment, affordable to users and can balance the current and future needs. This work covers the implementation of surveying techniques in the route selection for Baghdad Metro Tube. The travel demand has been assessed through an extensive travel potential survey. The public bus terminals were considered as a major source of data. The number of passengers using the present public transportation system from each bus terminal and for each route to various destinations has been recorded. The passenger supply points have been indicated by latitude and longitude that define the bus stop and the proposed metro route using global positioning system GPS. A passenger counting data was collected concerning the present use of public transport. A line indicates travel from one area to another and a grid was constructed. The present bus routes were identified, and the 28 major and minor public transportation terminals, which represent the passenger trip origin and destination nodes, were detected using GPS. The bus terminals were also positioned by the GPS and affixed. The recent land use of Baghdad urban area and the existing transportation network as obtained from Google earth were utilized in the geographic information system GIS environment. Travel corridors are identified and analyzed according to their existing right-of-way conditions, transit services, land use, and demographics.The positive and negative attributes of each corridor with regards to their potential for supporting transitoriented development TOD and higher capacity transit services have been determined through optimization process in the GIS. Finally, five corridors of the highest trip potential have been selected and proposed.
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Le, Guan, William J. Burke, Robert F. Pfaff, Henry Freudenreich, Stefan Maus i Hermann Luhr. "C/NOFS measurements of ring current magnetic field in low-latitude ionosphere". W 2014 XXXIth URSI General Assembly and Scientific Symposium (URSI GASS). IEEE, 2014. http://dx.doi.org/10.1109/ursigass.2014.6929830.

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Sridhar, M., D. Venkata Ratnam, B. Sirisha, Ch Rupesh Sasanka, B. Saketh Kumar, Ch Ajay, K. Padma Raju i Ch Srinivasa Rao. "Characterization of low latitude ionospheric scintillations using EEMD - DFA method". W 2015 International Conference on Innovations in Information,Embedded and Communication Systems (ICIIECS). IEEE, 2015. http://dx.doi.org/10.1109/iciiecs.2015.7193046.

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Dear, Varuliantor, Iskandar i Adit Kurniawan. "Performance of Tone Modulation Waveform Over Low Latitude Ionospheric Channel". W 2019 IEEE 13th International Conference on Telecommunication Systems, Services, and Applications (TSSA). IEEE, 2019. http://dx.doi.org/10.1109/tssa48701.2019.8985453.

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Tongkasem, Napat, Lin M. M. Myint i Pornchai Supnithi. "Precise total electron content map monitoring in low latitude region". W 2022 37th International Technical Conference on Circuits/Systems, Computers and Communications (ITC-CSCC). IEEE, 2022. http://dx.doi.org/10.1109/itc-cscc55581.2022.9895007.

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Dey, Abhijit, i Nirvikar Dashora. "Low latitude ionospheric effects: GNSS positioning at ionospheric anomaly peak region". W 2015 International Conference on Computers, Communications, and Systems (ICCCS). IEEE, 2015. http://dx.doi.org/10.1109/ccoms.2015.7562882.

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Trivedi, Nalin B., Santa Maria, Ícaro Vitorello, Wanderli Kabata, Severino L. G. Dutra, Antonio L. Padilha, Mauricio S. Bologna i in. "Geomagnetically induced currents – GIC in electric power system at low latitudes in Brazil: A case study". W 9th International Congress of the Brazilian Geophysical Society & EXPOGEF, Salvador, Bahia, Brazil, 11-14 September 2005. Society of Exploration Geophysicists and Brazilian Geophysical Society, 2005. http://dx.doi.org/10.1190/sbgf2005-402.

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B. Trivedi Convênio, Nalin, Santa Maria, Ícaro Vitorello, Wanderli Kabata, Severino L. G. Dutra, Antonio L. Padilha, Mauricio S. Bologna i in. "Geomagnetically induced currents – GIC in electric power system at low latitudes in Brazil: A case study". W 9th International Congress of the Brazilian Geophysical Society. European Association of Geoscientists & Engineers, 2005. http://dx.doi.org/10.3997/2214-4609-pdb.160.sbgf402.

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Raporty organizacyjne na temat "Low latitude current systems"

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Lawson i Thompson. L52100 Hot-Spot Protection for Impressed Current Systems. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), wrzesień 2003. http://dx.doi.org/10.55274/r0010153.

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As pipeline coating and associated cathodic protection (CP) systems age, areas along the pipeline inevitably develop that fall below a prescribed CP criterion. In efforts to meet an adequate CP criterion, engineers often resort to supplementing their existing CP system with magnesium anodes at these "low" potential areas resulting in a "hybrid" cathodic protection system consisting of an impressed current CP system (ICCP) supplemented with magnesium (Mg) anodes. This often achieves the desired result i.e. the potential measured over the pipe becomes more negative. However, there remain several unanswered questions concerning the real benefits to the polarization level of the pipe and the overall effect on the impressed current cathodic protection system. The primary objective of this PRCI project was to develop a better understanding of the relationship between ICCP systems and Mg anodes installed as hot-spot protection. This understanding will assist CP engineers in the design and operation of effective, economic CP systems.
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Johnson, Karl, Vagelis Vossos, Margarita Kloss, Gerald Robinson i Rich Brown. Direct Current as an Integrating Platform for ZNE Buildings with EVs and Storage: DC Direct Systems – A Bridge to a Low Carbon Future? Office of Scientific and Technical Information (OSTI), wrzesień 2016. http://dx.doi.org/10.2172/1408478.

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Leoni, Paolo, Ralf-Roman Schmidt, Roman Geyer i Patrick Reiter. SWOT analysis of ST integration in DHC systems. IEA SHC Task 55, luty 2020. http://dx.doi.org/10.18777/ieashc-task55-2020-0002.

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Solar thermal (ST) energy is one of the few renewable heat sources that is available almost everywhere and can bring multiple benefits to district heating and cooling (DHC) networks (on an environmental and systemic level) with very low operation costs and risks. However, the current share of ST in DHC networks is almost zero on a global scale.
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Jiang, Yuxiang. Unsettled Technology Areas in Electric Propulsion Systems. SAE International, maj 2021. http://dx.doi.org/10.4271/epr2021012.

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Electric vehicle (EV) transmission technology—crucial for battery electric vehicles (BEVs) and hybrid electric vehicles (HEVs)—is developing quickly and customers want good performance at a low cost. Single-speed gearboxes are popular in electric drive systems due to their simple and cost-effective configuration. However, multispeed gearboxes are being taken to market due to their higher low-speed torque, dynamic performance, and energy efficiency. Unsettled Technology Areas in Electric Propulsion Systems reviews the economic drivers, existing techniques, and current challenges of EV transmission technology—including torque interruption during shifting; thermal and sealing issues; and noise, vibration, and harshness (NVH). This report discusses the pros and cons for both single-speed and multispeed gearboxes with numerical analysis.
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Hayes, Anne M., Eileen Dombrowski, Allison H. Shefcyk i Jennae Bult. Learning Disabilities Screening and Evaluation Guide for Low- and Middle-Income Countries. RTI Press, kwiecień 2018. http://dx.doi.org/10.3768/rtipress.2018.op.0052.1804.

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Learning disabilities are among the most common disabilities experienced in childhood and adulthood. Although identifying learning disabilities in a school setting is a complex process, it is particularly challenging in low- and middle-income countries that lack the appropriate resources, tools, and supports. This guide provides an introduction to learning disabilities and describes the processes and practices that are necessary for the identification process. It also describes a phased approach that countries can use to assess their current screening and evaluation services, as well as determine the steps needed to develop, strengthen, and build systems that support students with learning disabilities. This guide also provides intervention recommendations that teachers and school administrators can implement at each phase of system development. Although this guide primarily addresses learning disabilities, the practices, processes, and systems described may be also used to improve the identification of other disabilities commonly encountered in schools.
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Moore, Mark, i Marla Spivack. The Way Forward in Analyzing National Educational Systems: A Re-Considered View. Research on Improving Systems of Education (RISE), sierpień 2022. http://dx.doi.org/10.35489/bsg-risewp_2022/110.

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Low- and middle-income countries around the world face a profound educational challenge. At stake in meeting this challenge is their ability to participate effectively in an increasingly interdependent global economy, society, and polity, and to meet many other goals set out in the International Declaration of Human Rights. Turning the current challenge into an important opportunity will, by definition, require significant improvements in the productivity of national education systems. Productivity changes on this scale require innovations at all three levels of the national systems: micro (classroom pedagogy), meso (school and district management), and macro (national politics and policy) levels. This paper sets out principles for designing a process initiated and supported at the national level that can animate, guide, and evaluate the varied innovations that will help national government meet their educational goals along a path that supports their economic, social, and political goals as well.
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Parkins. L51623 Environment Sensitive Cracking (Low pH Stress-Corrosion Cracking) of High Pressure Pipelines. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), sierpień 1990. http://dx.doi.org/10.55274/r0010308.

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This is a review of the current situation relating to transgranular environment sensitive cracking of the type experienced on an in-service pipeline, by comparison with the commoner intergranular cracking experienced on many systems. It is probable that the cracking is not unique. Quite apart from the crack paths, there are other significant differences between the conditions in which the two types of cracking occur, particularly in relation to the environments involved, and sufficiently so to indicate that the mechanisms of cracking are different. The circumstances in which the two types of environment form are discussed. If the creation of a reliable model for practical application to transgranular cracking is to be achieved, there is need for data relating to the effects of stressing conditions upon the crack nucleation and� growth rates of such cracks and of the circumstances in which these cracks coalesce.
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Macdonald. L51750 New Technique to Assess Level of Cathodic Protection in Underground Pipe Systems (Phases I and II). Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), luty 1996. http://dx.doi.org/10.55274/r0010611.

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This report introduces the Variable Frequency Impedance Tomography (VFIT) method for assessing the effectiveness of non-interruptible power supplies (sacrificial anodes) for protecting coated buried pipe. This method imposes a low-amplitude alternating voltage between the pipe and a reference electrode placed on the surface. A potentiostat/galvanostat controls the electric potential by modulating the current between the pipe and a surface counter electrode. The principle interpretive tool used in this study was an Artificial Neural Network (ANN) that had been \trained\" on simulated pipe with a defective coating and on field data from a test pipe.
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Johra, Hicham. Performance overview of caloric heat pumps: magnetocaloric, elastocaloric, electrocaloric and barocaloric systems. Department of the Built Environment, Aalborg University, styczeń 2022. http://dx.doi.org/10.54337/aau467469997.

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Heat pumps are an excellent solution to supply heating and cooling for indoor space conditioning and domestic hot water production. Conventional heat pumps are typically electrically driven and operate with a vapour-compression thermodynamic cycle of refrigerant fluid to transfer heat from a cold source to a warmer sink. This mature technology is cost-effective and achieves appreciable coefficients of performance (COP). The heat pump market demand is driven up by the urge to improve the energy efficiency of building heating systems coupled with the increase of global cooling needs for air-conditioning. Unfortunately, the refrigerants used in current conventional heat pumps can have a large greenhouse or ozone-depletion effect. Alternative gaseous refrigerants have been identified but they present some issues regarding toxicity, flammability, explosivity, low energy efficiency or high cost. However, several non-vapour-compression heat pump technologies have been invented and could be promising alternatives to conventional systems, with potential for higher COP and without the aforementioned refrigerant drawbacks. Among those, the systems based on the so-called “caloric effects” of solid-state refrigerants are gaining large attention. These caloric effects are characterized by a phase transition varying entropy in the material, resulting in a large adiabatic temperature change. This phase transition is induced by a variation of a specific external field applied to the solid refrigerant. Therefore, the magnetocaloric, elastocaloric, electrocaloric and barocaloric effects are adiabatic temperature changes in specific materials when varying the magnetic field, uniaxial mechanical stress, electrical field or hydrostatic pressure, respectively. Heat pump cycle can be built from these caloric effects and several heating/cooling prototypes were developed and tested over the last few decades. Although not a mature technology yet, some of these caloric systems are well suited to become new efficient and sustainable solutions for indoor space conditioning and domestic hot water production. This technical report (and the paper to which this report is supplementary materials) aims to raise awareness in the building community about these innovative caloric systems. It sheds some light on the recent progress in that field and compares the performance of caloric systems with that of conventional vapour-compression heat pumps for building applications.
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Mizrach, Amos, Sydney L. Spahr, Ephraim Maltz, Michael R. Murphy, Zeev Schmilovitch, Jan E. Novakofski, Uri M. Peiper i in. Ultrasonic Body Condition Measurements for Computerized Dairy Management Systems. United States Department of Agriculture, 1993. http://dx.doi.org/10.32747/1993.7568109.bard.

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The body condition (BC) score is recognized in the dairy industry as an essential tool for managing the energy reserves of the dairy cow, which is essential for sustaining optimal and efficient production over several lactations. The current use of BC scoring depends on the accuracy of subjective visual estimates, and this limits its kusefulness as a management aid in the dairy industry. A measuring tool that would frequently provide objective data on the cow's body reserves would be a major contribution to efficient dairy herd management. Ultrasonic sensors have the potential to be developed into an efficient BC measuring device, and the experimental use of such sensors for subcutaneous fat thickness (SDFT) estimates, as an indication for BC in beef cattle, supports this assumption. The purposes of this project were: 1. To compare visual BC scoring and ultrasonic fat thickness with on-line automated body weight (BW) measurements as monitors of nutritional adequacy of dairy cows at various stages of lactation. 2. To determine the effects of variation in digestive fill in early and late lactation on the accuracy of body weight measurements in lactating cows. 3. To modify an existing ultrasonic system and develop a specialized, low-cost sensor for repeatable determination of body condition scores by users with minimal training and skill. 4. To develop a standard for the assignment of body condition scores based on ultrasonic measurements of subdermal fat thickness. The procedure to execute these objectives involved: 1. Frequent measurement of BW, milk yield (MY), BC (visually scored) and subdermal fat thickness ultrasonically measured of dairy cows, and data analysis on average and individual basis. 2. Testing and selection of an appropriate special-purpose sensor, finding an optimum body location for working an ultrasonic measurement, prcessing the signals obtained, and correlating the resulting measurements with performance responses in lactating cows. Linking the ultrasonic signals to BC scores, and developing a BC scoring data acquisition system are the first steps towards fulfilling the necessary requirements for incorporating this device into an existing dairy herd management system, in order to provide the industry with a powerful managment tool. From the results obtained we could conclude that: 1. BC does not correlate with BW changes during all stages of lactation, although in general terms it does. These results were confirmed by individual cow BW and BC data obtained during the course of lactation, that were supported by individual objective ultrasonic measurement of SDFT. 2. BW changes reflect energy metabolism reliably ony after peak milk yield; early in lactation, a decrease in BW expresses mobilization of body reserves only qualitatively, and not quantitatively. 3. Gastrointestinal content increases throughout the whole period during which dry matter intake (DMI) increases. The drastic increase very early in lactation prevents the use of BW changes as a basis for quantitative estimatio of energy meatabolism; at this stage of lactation, konly a BC score or any other direct measurements willl provide a quantitative estimate of energy metabolism. 4. Ultrasonic measurements of subdermal fat thickness can be used to quantify changes that correlate with the actual condition of the cow, as assessed by performance and the traditional way of scoring. 5. To find the best site on the cow's body at which to obtain responses to BC and its changes in the course of lactation, additional sites have to be examined. From the present study, it seems that the sites between ribs 12 and 13 have the potential for this purpose. 6. The use of templates made it easier to repeat measurements at a desired site and spot. However, the convenient easy-to-handle way to standardize the measurement, described in this study, koffers scope for improvement. 7. The RF peak values of the A-mode are better indicators of the location of fat layer borders than image analysis, from the point of view of future commercial development. 8. The distances between the RF peaks of the A-mode can be automatically measured by suitable software, for future commercial development. 9. Proper analysis of daily body weight and milk yield data can provide the necessary information on body condition changes during lactation, until a direct BC measurement device is developed. 10. In any case, at least one visual BC assessment has to be done, preferably immediately after calving, for calibration purposes.
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