WorldWideScience

Sample records for mri system energy

  1. Superconductive MRI system, FLEXARTTM

    International Nuclear Information System (INIS)

    Suzuki, Hirokazu; Nishikawa, Mineki; Goro, Takehiko

    1994-01-01

    Since the establishment of TAMI (Toshiba America MRI Inc.) in 1989, it has been jointly working with Toshiba on developing a new infrastructure for computer and software technologies to be applied to new MRI (magnetic resonance imaging) systems. As a result of these efforts, the first product of a new series of MRI systems has been introduced on the market. Known as FLEXART TM (a newly created word combining FLEXible and ART), this MRI system incorporates a new 32-bit RISC computer and a new controller for pulse sequences and data acquisition. The product concepts of FLEXART TM are high image quality, high patient throughput, and ease of use, all of which are necessary features for an MRI system in the premium mid-field MRI market segment. (author)

  2. VISARTTM superconducting MRI system

    International Nuclear Information System (INIS)

    Usui, Yoshiyuki; Goro, Takehiko; Yamagata, Hitoshi.

    1995-01-01

    We have developed VISART TM , a 1.5 T high-field magnetic resonance imaging (MRI) system based on technology developed for both the FLEXART TM (0.5T) and MRT-200/GP (1.5T) systems as the first and second products, respectively, of a new series of MRI systems. VISART TM is a newly coined word combining VISion and state-of-the-ART. A higher power gradient system and new high-speed imaging techniques have been developed to meet the market demand for higher resolution images and shorter scan times. The product concepts of VISART TM are high image quality, high patient throughput, flexible clinical application, and ease of use, all of which are essential features for an MRI system in the high-field MRI market segment. (author)

  3. Musculoskeletal MRI: dedicated systems

    International Nuclear Information System (INIS)

    Masciocchi, C.; Barile, A.; Satragno, L.

    2000-01-01

    The ''dedicated'' MRI units have characteristics of high diagnostic accuracy and lower installation and management costs as compared with whole-body systems. The dedicated MRI units are easy to install. The low weight allows their installation also under unfavorable circumstances. In a dedicated system cost-effectiveness and ease of installation must be accompanied by the capability of providing high-quality images. In our experience, the high number of examinations performed, the most part of which provided with the surgical controls, allowed an accurate evaluation of the diagnostic potentialities of the dedicated magnet. We were not able to perform the examinations in only 3 % of cases due to the physical shape of the patient and the clinical condition of the patient which may hinder the correct positioning of the limb. The overlapping of the diagnostic accuracy of the E-scan and Artoscan units in the study of the lower limbs, compared with whole-body units and surgery, prompted us to exploit the potentialities of the E-Scan in the study of the shoulder. We had a good correlation between E-Scan, whole-body units, and surgical findings, which confirmed the high diagnostic accuracy of the dedicated system. In conclusion, in our experience carried out in the musculoskeletal system, the dedicated magnets showed promising results. Their diagnostic reliability and utility was comparable to that obtained from conventional units operating at higher magnetic fields. (orig.)

  4. Superconducting magnet systems for MRI

    International Nuclear Information System (INIS)

    Hawksworth, D.G.

    1988-01-01

    MRI is the first large scale commercial application of superconductivity and has not achieved the status of a mature industry with an annual turnover in the magnet industry alone in excess of $150M. Conservative estimates put the investment of the medical industry in MRI as a whole at more than a billion dollars. In the nine years since shipment of the first superconducting whole body imaging magnets of 0.3 Tesla field the standard product of the industry has become a system of 1 meter bore and field strength 0.5 Tesla to 1.5 Tesla. In this paper the evolution of present day MRI magnets from small bore but high field spectrometer magnets is reviewed and the direction of future developments discussed

  5. Central nervous system tuberculosis: MRI

    Energy Technology Data Exchange (ETDEWEB)

    Kioumehr, F.; Dadsetan, M.R.; Rooholamini, S.A.; Au, A.

    1994-02-01

    The MRI findings of 18 proven cases of central nervous system (CNS) tuberculosis were reviewed; 10 patients were seropositive for HIV. All had medical, laboratory, or surgical proof of CNS tuberculosis. Eleven patients had meningitis, of whom two also had arachnoiditis. Five patients had focal intra-axial tuberculomas: four brain masses and one an intramedullary spinal lesion. Two patients had focal extra-axial tuberculomas: one in the pontine cistern, and one in the spine. In all 11 patients with meningitis MRI showed diffuse, thick, meningeal enhancement. All intraparenchymal tuberculomas showed low signal intensity on T2-weighted images and ring or nodular enhancement. The extra-axial tuberculomas had areas isointense or hypointense relative to normal brain and spinal cord on T2-weighted images. Although tuberculous meningitis cannot be differentiated from other meningitides on the basis of MR findings, intraparenchymal tuberculomas show characteristic T2 shortening, not found in most other space-occupying lesions. In the appropriate clinical setting, tuberculoma should be considered. (orig.)

  6. Interference between PET and MRI sub-systems in a silicon-photomultiplier-based PET/MRI system

    International Nuclear Information System (INIS)

    Yamamoto, Seiichi; Watabe, Hiroshi; Kanai, Yasukazu; Hatazawa, Jun; Aoki, Masaaki; Sugiyama, Eiji; Watabe, Tadashi; Imaizumi, Masao; Shimosegawa, Eku

    2011-01-01

    The silicon-photomultiplier (Si-PM) is a promising photodetector, especially for integrated PET/MRI systems, due to its small size, high gain, and low sensitivity to static magnetic fields. The major problem using a Si-PM-based PET system within the MRI system is the interference between the PET and MRI units. We measured the interference by combining a Si-PM-based PET system with a permanent-magnet MRI system. When the RF signal-induced pulse height exceeded the lower energy threshold level of the PET system, interference between the Si-PM-based PET system and MRI system was detected. The prompt as well as the delayed coincidence count rates of the Si-PM-based PET system increased significantly. These noise counts produced severe artifacts on the reconstructed images of the Si-PM-based PET system. In terms of the effect of the Si-PM-based PET system on the MRI system, although no susceptibility artifact was observed on the MR images, electronic noise from the PET detector ring was detected by the RF coil and reduced the signal-to-noise ratio (S/N) of the MR images. The S/N degradation of the MR images was reduced when the distance between the RF coil and the Si-PM-based PET system was increased. We conclude that reducing the interference between the PET and MRI systems is essential for achieving the optimum performance of integrated Si-PM PET/MRI systems.

  7. High magnetic field MRI system

    International Nuclear Information System (INIS)

    Maeda, Hideaki; Urata, Masami; Satoh, Kozo

    1990-01-01

    A high field superconducting magnet, 4-5 T in central magnetic field, is required for magnetic resonance spectroscopic imaging (MRSI) on 31 P, essential nuclei for energy metabolism of human body. This paper reviews superconducting magnets for high field MRSI systems. Examples of the cross-sectional image and the spectrum of living animals are shown in the paper. (author)

  8. Energy Preserved Sampling for Compressed Sensing MRI

    Directory of Open Access Journals (Sweden)

    Yudong Zhang

    2014-01-01

    Full Text Available The sampling patterns, cost functions, and reconstruction algorithms play important roles in optimizing compressed sensing magnetic resonance imaging (CS-MRI. Simple random sampling patterns did not take into account the energy distribution in k-space and resulted in suboptimal reconstruction of MR images. Therefore, a variety of variable density (VD based samplings patterns had been developed. To further improve it, we propose a novel energy preserving sampling (ePRESS method. Besides, we improve the cost function by introducing phase correction and region of support matrix, and we propose iterative thresholding algorithm (ITA to solve the improved cost function. We evaluate the proposed ePRESS sampling method, improved cost function, and ITA reconstruction algorithm by 2D digital phantom and 2D in vivo MR brains of healthy volunteers. These assessments demonstrate that the proposed ePRESS method performs better than VD, POWER, and BKO; the improved cost function can achieve better reconstruction quality than conventional cost function; and the ITA is faster than SISTA and is competitive with FISTA in terms of computation time.

  9. Energy systems

    International Nuclear Information System (INIS)

    Haefele, W.

    1974-01-01

    Up to the present the production, transmission and distribution of energy has been considered mostly as a fragmented problem; at best only subsystems have been considered. Today the scale of energy utilization is increasing rapidly, and correspondingly, the reliance of societies on energy. Such strong quantitative increases influence the qualitative nature of energy utilization in most of its aspects. Resources, reserves, reliability and environment are among the key words that may characterize the change in the nature of the energy utilization problem. Energy can no longer be considered an isolated technical and economical problem, rather it is embedded in the ecosphere and the society-technology complex. Restraints and boundary conditions have to be taken into account with the same degree of attention as in traditional technical problems, for example a steam turbine. This results in a strong degree of interweaving. Further, the purpose of providing energy becomes more visible, that is, to make survival possible in a civilized and highly populated world on a finite globe. Because of such interweaving and finiteness it is felt that energy should be considered as a system and therefore the term 'energy systems' is used. The production of energy is only one component of such a system; the handling of energy and the embedding of energy into the global and social complex in terms of ecology, economy, risks and resources are of similar importance. he systems approach to the energy problem needs more explanation. This paper is meant to give an outline of the underlying problems and it is hoped that by so doing the wide range of sometimes confusing voices about energy can be better understood. Such confusion starts already with the term 'energy crisis'. Is there an energy crisis or not? Much future work is required to tackle the problems of energy systems. This paper can only marginally help in that respect. But it is hoped that it will help understand the scope of the

  10. Energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Haefele, W [Nuclear Research Centre, Applied Systems Analysis and Reactor Physics, Karlsruhe (Germany); International Institute for Applied Systems Analysis, Laxenburg (Austria)

    1974-07-01

    Up to the present the production, transmission and distribution of energy has been considered mostly as a fragmented problem; at best only subsystems have been considered. Today the scale of energy utilization is increasing rapidly, and correspondingly, the reliance of societies on energy. Such strong quantitative increases influence the qualitative nature of energy utilization in most of its aspects. Resources, reserves, reliability and environment are among the key words that may characterize the change in the nature of the energy utilization problem. Energy can no longer be considered an isolated technical and economical problem, rather it is embedded in the ecosphere and the society-technology complex. Restraints and boundary conditions have to be taken into account with the same degree of attention as in traditional technical problems, for example a steam turbine. This results in a strong degree of interweaving. Further, the purpose of providing energy becomes more visible, that is, to make survival possible in a civilized and highly populated world on a finite globe. Because of such interweaving and finiteness it is felt that energy should be considered as a system and therefore the term 'energy systems' is used. The production of energy is only one component of such a system; the handling of energy and the embedding of energy into the global and social complex in terms of ecology, economy, risks and resources are of similar importance. he systems approach to the energy problem needs more explanation. This paper is meant to give an outline of the underlying problems and it is hoped that by so doing the wide range of sometimes confusing voices about energy can be better understood. Such confusion starts already with the term 'energy crisis'. Is there an energy crisis or not? Much future work is required to tackle the problems of energy systems. This paper can only marginally help in that respect. But it is hoped that it will help understand the scope of the

  11. Superconducting MRI system, MRT-50A

    International Nuclear Information System (INIS)

    Sugimoto, Hiroshi; Asahina, Kiyotaka

    1987-01-01

    The writers' developmental work on MRI (magnetic resonance imaging) was started in 1983. The model used first was MRT-15A (0.15 T). The next model was MRT-22A (0.22 T) which had a magnetic self-shield. As for the development of superconducting MRI system, they started clinical evaluation at Toshiba Central Hospital MRI Center in 1984 and got the official approval in 1985. For the model, use was made of MRT-50A (0.5 T) employing a superconducting magnet made by Toshiba. Herein represented are the basis of the images obtained through MRT-50 and the fact that the application fields of MRI are going on increasing (not only to brain and spine areas but also to the areas of the chest, abdomen and joints), and also the results of the work-in-progress of application software. (author)

  12. MRI

    DEFF Research Database (Denmark)

    Schroeter, Aileen; Rudin, Markus; Gianolio, Eliana

    2017-01-01

    This chapter discusses principles of nuclear magnetic resonance (NMR) and MRI followed by a survey on the major classes of MRI contrast agents (CA), their modes of action, and some of the most significative applications. The two more established classes of MRI-CA are represented by paramagnetic...... been attained that markedly increase the number and typology of systems with CEST properties. Currently much attention is also devoted to hyperpolarized molecules that display a sensitivity enhancement sufficient for their direct exploitation for the formation of the MR image. A real breakthrough...

  13. Shimadzu superconductive MRI system, SMT-100

    International Nuclear Information System (INIS)

    Yamauchi, Mikio; Shimizu, Koji; Itoh, Masamichi; Fujio, Yasuo; Hashimoto, Yasushi

    1989-01-01

    The magnetic resonance imaging (MRI) system SMT-100 operating at 1.0 T (Tesla) developed lately is reported on this paper. SMT-100 is graded as higher class and more effective system in MR-imaging systems. Purpose of development are (1) supply of high quality imaging, (2) high patient throughput, and (3) low operating cost. Following developments are carried out in this system: (1) development of 1.0 T superconducting magnet without liquid nitrogen vessel, attached self-magnetic shield, (2) development of digital controller system for being able to correspond to future pulse sequences, (3) development of flexible coil and establishment of displacement scanning method by fitting the coil on examination position, (4) separate console system (viewing console and scanning console) for high patient throughput. The outline of SMT-100 and clinical data by the system are reported here. (author)

  14. Cardiac MRI in patients with complex CHD following primary or secondary implantation of MRI-conditional pacemaker system.

    Science.gov (United States)

    Al-Wakeel, Nadya; O h-Ici, Darach; Schmitt, Katharina R; Messroghli, Daniel R; Riesenkampff, Eugénie; Berger, Felix; Kuehne, Titus; Peters, Bjoern

    2016-02-01

    In patients with CHD, cardiac MRI is often indicated for functional and anatomical assessment. With the recent introduction of MRI-conditional pacemaker systems, cardiac MRI has become accessible for patients with pacemakers. The present clinical study aims to evaluate safety, susceptibility artefacts, and image reading of cardiac MRI in patients with CHD and MRI-conditional pacemaker systems. Material and methods CHD patients with MRI-conditional pacemaker systems and a clinical need for cardiac MRI were examined with a 1.5-T MRI system. Lead function was tested before and after MRI. Artefacts and image readings were evaluated using a four-point grading scale. A total of nine patients with CHD (mean age 34.0 years, range 19.5-53.6 years) received a total of 11 cardiac MRI examinations. Owing to clinical indications, seven patients had previously been converted from conventional to MRI-conditional pacemaker systems. All MRI examinations were completed without adverse effects. Device testing immediately after MRI and at follow-up showed no alteration of pacemaker device and lead function. Clinical questions could be addressed and answered in all patients. Cardiac MRI can be performed safely with high certainty of diagnosis in CHD patients with MRI-conditional pacemaker systems. In case of clinically indicated lead and box changing, CHD patients with non-MRI-conditional pacemaker systems should be considered for complete conversion to MRI-conditional systems.

  15. MRI device – alternative for electrical energy storage

    Directory of Open Access Journals (Sweden)

    Molokáč, Š.

    2008-01-01

    Full Text Available It is well known, that the electrical energy storage in the large scale is basically difficult process. Such a process is marked by the energy losses, as the conversion of electrical energy into another form, is most frequently for example mechanical, and then back to the primary electrical form. Though, the superconducting magnetic energy storage (SMES technology offers the energy storage in an unchanged form, which is advantageous primarily in the achieved efficiency. Magnetic resonance imaging (MRI devices, commonly used in the medical facilities are based on the application of superconducting magnet. After its rejection from operation, there is possibility of using such devices for energy storage purposes. Additionally, such a technology of storage is also ecological.

  16. Using MRI devices for the energy storage purposes

    Directory of Open Access Journals (Sweden)

    Štefan Molokáč

    2007-04-01

    Full Text Available It is well known, that the electrical energy storage in the large scale is basically a difficult process. Such a process is connected with energy losses, as most frequently it is the conversion of electrical energy into another form, for example mechanical, and then back to the primal electrical form. Though, the SMES technology offers the energy storage in an unchanged form, which is advantageous primarily in the achieved efficiency. The magnetic resonance imaging (MRI devices, commonly used in the medical facilities are based on the basis of superconducting magnet. After its rejection from operation, (basically caused only by its „software fustiness“ and not by functional faults, there is a possibility of using such devices for the energy storage purposes. Additionally, such a technology of storage is also ecological. A research project is running at the Faculty of Mining, Ecology, Process Control and Geotechnologies (F BERG, the Department of Business and Management, in the field of using rejected MRI for energy storage purposes.

  17. Energy infrastructure: hydrogen energy system

    Energy Technology Data Exchange (ETDEWEB)

    Veziroglu, T N

    1979-02-01

    In a hydrogen system, hydrogen is not a primary source of energy, but an intermediary, an energy carrier between the primary energy sources and the user. The new unconventional energy sources, such as nuclear breeder reactors, fusion reactors, direct solar radiation, wind energy, ocean thermal energy, and geothermal energy have their shortcomings. These shortcomings of the new sources point out to the need for an intermediary energy system to form the link between the primary energy sources and the user. In such a system, the intermediary energy form must be transportable and storable; economical to produce; and if possible renewable and pollution-free. The above prerequisites are best met by hydrogen. Hydrogen is plentiful in the form of water. It is the cheapest synthetic fuel to manufacture per unit of energy stored in it. It is the least polluting of all of the fuels, and is the lightest and recyclable. In the proposed system, hydrogen would be produced in large plants located away from the consumption centers at the sites where primary new energy sources and water are available. Hydrogen would then be transported to energy consumption centers where it would be used in every application where fossil fuels are being used today. Once such a system is established, it will never be necessary to change to any other energy system.

  18. Wind energy systems

    Science.gov (United States)

    Stewart, H. J.

    1978-01-01

    A discussion on wind energy systems involved with the DOE wind energy program is presented. Some of the problems associated with wind energy systems are discussed. The cost, efficiency, and structural design of wind energy systems are analyzed.

  19. Superconductive MRI system, MRT-50A/SUPER

    International Nuclear Information System (INIS)

    Suzuki, Hirokazu; Goro, Takehiko

    1992-01-01

    The MRI (magnetic resonance imaging) market has been rapidly growing and more than 1,300 MRI systems are now operating in the Japanese domestic market. An upper-middle range MRI market, which is characterized by high-image quality, has newly appeared between the high-end and middle-range market niches since last year. To be competitive in this upper-middle range market, Toshiba has developed a superconductive MRI system, the MRT-50A/SUPER. The new system featured a high-performance actively shielded gradient coil called the TSGC (twin-shielded gradient coil), installed in a compact superconductive magnet. This paper introduces the MRT-50A/SUPER and describes recent developments in MRI technology. (author)

  20. Neurodegenerative diseases of the central motor system in MRI

    International Nuclear Information System (INIS)

    Alfke, K.

    2005-01-01

    Neurodegenerative diseases of the central motor system often lead to discrete but functionally important parenchymal abnormalities in various parts of the brain. MRI is the most sensitive imaging method to detect these abnormalities. Various neurodegenerative diseases are presented with their clinical symptoms and MRI findings. Criteria for differential diagnosis are provided as well. (orig.)

  1. Abnormal muscle MRI in a patient with systemic juvenile arthritis

    International Nuclear Information System (INIS)

    Miller, M.L.; Levinson, L.; Pachman, L.M.; Poznanski, A.

    1995-01-01

    Although myositis has been described in children with systemic-onset juvenile arthritis (JA), its documentation by MRI has not been reported. We describe a 13-year-old boy with systemic-onset JA, severe myalgia, and elevated muscle enzymes, but normal muscle strength, who had an MRI consistent with myositis. Magnetic resonance imaging can identify the specific location of myositis, allowing more precise definition of a potential complication of systemic JA. (orig.)

  2. Abnormal muscle MRI in a patient with systemic juvenile arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M.L. [Dept. of Pediatrics, Northwestern Univ. Medical School, Chicago, IL (United States); Levinson, L. [Dept. of Pediatrics, Northwestern Univ. Medical School, Chicago, IL (United States); Pachman, L.M. [Dept. of Pediatrics, Northwestern Univ. Medical School, Chicago, IL (United States); Poznanski, A. [Dept. of Radiology, Northwestern Univ. Medical School, Chicago, IL (United States)

    1995-11-01

    Although myositis has been described in children with systemic-onset juvenile arthritis (JA), its documentation by MRI has not been reported. We describe a 13-year-old boy with systemic-onset JA, severe myalgia, and elevated muscle enzymes, but normal muscle strength, who had an MRI consistent with myositis. Magnetic resonance imaging can identify the specific location of myositis, allowing more precise definition of a potential complication of systemic JA. (orig.)

  3. Energy Information Systems

    Science.gov (United States)

    Home > Building Energy Information Systems and Performance Monitoring (EIS-PM) Building Energy evaluate and improve performance monitoring tools for energy savings in commercial buildings. Within the and visualization capabilities to energy and facility managers. As an increasing number of

  4. MRI

    Science.gov (United States)

    ... the room. Pins, hairpins, metal zippers, and similar metallic items can distort the images. Removable dental work ... an MRI can cause heart pacemakers and other implants not to work as well. The magnets can ...

  5. Croatian Energy System Defossilization

    International Nuclear Information System (INIS)

    Potocnik, V.

    2013-01-01

    Defossilization of an energy system, as primary cause of the actual climate change, means exchange of predominantly imported fossil fuels with climate more convenient energy carriers, facilitating thus the way out of crisis.Overview of the world and Croatian energy system situation is presented as well as the overview of climate change. The most important Croatian energy system defossilization measures-energy efficiency increase, renewable energy inclusion and others - are described.(author)

  6. The OMERACT rheumatoid arthritis magnetic resonance imaging (MRI) scoring system

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Peterfy, Charles G.; Bird, Paul

    2017-01-01

    Objective: The Outcome Measures in Rheumatology (OMERACT) Rheumatoid Arthritis (RA) Magnetic Resonance Imaging (MRI) scoring system (RAMRIS), evaluating bone erosion, bone marrow edema/osteitis, and synovitis, was introduced in 2002, and is now the standard method of objectively quantifying...... inflammation and damage by MRI in RA trials. The objective of this paper was to identify subsequent advances and based on them, to provide updated recommendations for the RAMRIS. Methods: MRI studies relevant for RAMRIS and technical and scientific advances were analyzed by the OMERACT MRI in Arthritis Working...... Group, which used these data to provide updated considerations on image acquisition, RAMRIS definitions, and scoring systems for the original and new RA pathologies. Further, a research agenda was outlined. Results: Since 2002, longitudinal studies and clinical trials have documented RAMRIS variables...

  7. Energy systems security

    CERN Document Server

    Voeller, John G

    2014-01-01

    Energy Systems Security features articles from the Wiley Handbook of Science and Technology for Homeland Security covering topics related to electricity transmission grids and their protection, risk assessment of energy systems, analysis of interdependent energy networks. Methods to manage electricity transmission disturbances so as to avoid blackouts are discussed, and self-healing energy system and a nano-enabled power source are presented.

  8. Kinetic energy storage system

    Energy Technology Data Exchange (ETDEWEB)

    Jaeggi, M.; Folini, P.

    1983-09-03

    A flywheel system for the purpose of energy storage in decentral solar- or wind energy plants is introduced. The system comprises a rotor made out of plastic fibre, a motor/generator serving as electro-mechanical energy converter and a frequency-voltage transformer serving as electric adapter. The storable energy quantity amounts to several kWh.

  9. 19F-MRI of stomach and intestine using 50% FTPA emulsion under 2T MRI system

    International Nuclear Information System (INIS)

    Shimizu, Masahiro; Kobayashi, Teturou; Mishima, Hideyuki

    1991-01-01

    1 H-MRI is of clinical value in many lesions, but imaging of gastrointestinal lesions is still difficult by 1 H-MRI. To overcome this weak point of 1 H-MRI, rabbit stomachs were examined by 19 F-MRI using 50% FTPA emulsion. We also examined the stability of 50% FTPA emulsion in the stomach and its absorption from the gastrointestinal tract. We found that 50% FTPA emulsion was very stable at pH 1.5, and only a very small amount was absorbed. A rabbit (weighing 2 kg) was anesthetized, and 100 ml of 50% FTPA emulsion was infused into the stomach by catheter. 19 F-MRI was performed in this rabbit using a 2 T superconducting MRI system designed for human use, and clear pictures of the stomach were obtained. From our results we conclude that 19 F-MRI of the stomach using 50% FTPA emulsion is of practical value. (author)

  10. Superconductors Enable Lower Cost MRI Systems

    Science.gov (United States)

    2013-01-01

    The future looks bright, light, and green, especially where aircraft are concerned. The division of NASA s Fundamental Aeronautics Program called the Subsonic Fixed Wing Project is aiming to reach new heights by 2025-2035, improving the efficiency and environmental impact of air travel by developing new capabilities for cleaner, quieter, and more fuel efficient aircraft. One of the many ways NASA plans to reach its aviation goals is by combining new aircraft configurations with an advanced turboelectric distributed propulsion (TeDP) system. Jeff Trudell, an engineer at Glenn Research Center, says, "The TeDP system consists of gas turbines generating electricity to power a large number of distributed motor-driven fans embedded into the airframe." The combined effect increases the effective bypass ratio and reduces drag to meet future goals. "While room temperature components may help reduce emissions and noise in a TeDP system, cryogenic superconducting electric motors and generators are essential to reduce fuel burn," says Trudell. Superconductors provide significantly higher current densities and smaller and lighter designs than room temperature equivalents. Superconductors are also able to conduct direct current without resistance (loss of energy) below a critical temperature and applied field. Unfortunately, alternating current (AC) losses represent the major part of the heat load and depend on the frequency of the current and applied field. A refrigeration system is necessary to remove the losses and its weight increases with decreasing temperature. In 2001, a material called magnesium diboride (MgB2) was discovered to be superconducting. The challenge, however, has been learning to manufacture MgB2 inexpensively and in long lengths to wind into large coils while meeting the application requirements.

  11. [Microinjection Monitoring System Design Applied to MRI Scanning].

    Science.gov (United States)

    Xu, Yongfeng

    2017-09-30

    A microinjection monitoring system applied to the MRI scanning was introduced. The micro camera probe was used to stretch into the main magnet for real-time video injection monitoring of injection tube terminal. The programming based on LabVIEW was created to analysis and process the real-time video information. The feedback signal was used for intelligent controlling of the modified injection pump. The real-time monitoring system can make the best use of injection under the condition that the injection device was away from the sample which inside the magnetic room and unvisible. 9.4 T MRI scanning experiment showed that the system in ultra-high field can work stability and doesn't affect the MRI scans.

  12. A new MRI grading system for chondromalacia patellae.

    Science.gov (United States)

    Özgen, Ali; Taşdelen, Neslihan; Fırat, Zeynep

    2017-04-01

    Background Chondromalacia patellae is a very common disorder. Although magnetic resonance imaging (MRI) is widely used to investigate patellar cartilage lesions, there is no descriptive MRI-based grading system for chondromalacia patellae. Purpose To propose a new MRI grading system for chondromalacia patellae with corresponding high resolution images which might be useful in precisely reporting and comparing knee examinations in routine daily practice and used in predicting natural course and clinical outcome of the patellar cartilage lesions. Material and Methods High resolution fat-saturated proton density (FS PD) images in the axial plane with corresponding T2 mapping images were reviewed. A detailed MRI grading system covering the deficiencies of the existing gradings has been set and presented on these images. Two experienced observers blinded to clinical data examined 44 knee MR images and evaluated patellar cartilage changes according to the proposed grading system. Inter- and intra-rater validity testing using kappa statistics were calculated. Results A descriptive and detailed grading system with corresponding FS PD and T2 mapping images has been presented. Inter-rater agreement was 0.80 (95% confidence interval [CI], 0.71-0.89). Intra-rater agreements were 0.83 (95% CI, 0.74-0.91) for observer A and 0.79 (95% CI, 0.70-0.88) for observer B (k-values). Conclusion We present a new MRI grading system for chondromalacia patellae with corresponding images and good inter- and intra-rater agreement which might be useful in reporting and comparing knee MRI examinations in daily practice and may also have the potential for using more precisely predicting prognosis and clinical outcome of the patients.

  13. Clinical application of MRI to fetal central nervous system

    International Nuclear Information System (INIS)

    Wang Guangbing; Chen Liguang; Ma Yuxiang; Liu Wen; Lin Xiangtao; Shi Hao; Yang Zhenzhen; Qu Jun

    2005-01-01

    Objective: To explore the value of MRI on fetal central nervous system. Methods: Twenty-four women with complicated pregnancies, aged from 22 to 32 years (average 27 years) and with gestation from 23-39 weeks (average 30 weeks) were studied with a 1.5T superconductive MR unit within 24 hours after ultrasound studies. T 2 -weighted MR imaging was performed using HASTE and T 1 -weighted MR imaging was using FLASH. Comparison of the diagnosis of MRI and ultrasound were done with autopsy or postnatal follow-up MRI. Results: Of the 24 cases, 24 fetus were found. The fetal brain, gyrus, sulcus, corpus callosum, thalamus, cerebellum, brain stem, and spinal cord were shown more clearly on MR T 2 -weighted images. T 1 -weighted images were not as good as T 2 -weighted images. Twenty-seven lesions were visualized by ultrasound and thirty-one by MRI in these twenty-four fetuses. By MRI study, two cases were conformed their ultrasound diagnosis, ten cases were completed their ultrasound diagnosis, and twelve cases were made the same diagnosis as ultrasound. Conclusion: MR has advantages in displaying fetal central nervous system anatomy over ultrasound, the quality of MR images is not affected by maternal somatotype, volume of amniotic fluid, fetal skull and the pelvic skeleton of pregnant women. Based on ultrasound, MR imaging is a valuable complement to sonography in difficult cases, it can conforming, completing, even more correcting the diagnosis made by ultrasound. (authors)

  14. Solar energy conversion systems

    CERN Document Server

    Brownson, Jeffrey R S

    2013-01-01

    Solar energy conversion requires a different mind-set from traditional energy engineering in order to assess distribution, scales of use, systems design, predictive economic models for fluctuating solar resources, and planning to address transient cycles and social adoption. Solar Energy Conversion Systems examines solar energy conversion as an integrative design process, applying systems thinking methods to a solid knowledge base for creators of solar energy systems. This approach permits different levels of access for the emerging broad audience of scientists, engineers, architects, planners

  15. Renewable Energy Systems

    DEFF Research Database (Denmark)

    Lund, Henrik; Mathiesen, Brian Vad; Connolly, David

    2014-01-01

    on the electricity sector, smart energy systems include the entire energy system in its approach to identifying suitable energy infrastructure designs and operation strategies. The typical smart grid sole focus on the electricity sector often leads to the conclusion that transmission lines, flexible electricity......This paper presents the learning of a series of studies that analyse the problems and perspectives of converting the present energy system into a 100 % renewable energy system using a smart energy systems approach. As opposed to, for instance, the smart grid concept, which takes a sole focus...... are to be found when the electricity sector is combined with the heating and cooling sectors and/or the transportation sector. Moreover, the combination of electricity and gas infrastructures may play an important role in the design of future renewable energy systems. The paper illustrates why electricity smart...

  16. Wind energy analysis system

    OpenAIRE

    2014-01-01

    M.Ing. (Electrical & Electronic Engineering) One of the most important steps to be taken before a site is to be selected for the extraction of wind energy is the analysis of the energy within the wind on that particular site. No wind energy analysis system exists for the measurement and analysis of wind power. This dissertation documents the design and development of a Wind Energy Analysis System (WEAS). Using a micro-controller based design in conjunction with sensors, WEAS measure, calcu...

  17. Passive magnetic shielding in MRI-Linac systems

    Science.gov (United States)

    Whelan, Brendan; Kolling, Stefan; Oborn, Brad M.; Keall, Paul

    2018-04-01

    Passive magnetic shielding refers to the use of ferromagnetic materials to redirect magnetic field lines away from vulnerable regions. An application of particular interest to the medical physics community is shielding in MRI systems, especially integrated MRI-linear accelerator (MRI-Linac) systems. In these systems, the goal is not only to minimize the magnetic field in some volume, but also to minimize the impact of the shield on the magnetic fields within the imaging volume of the MRI scanner. In this work, finite element modelling was used to assess the shielding of a side coupled 6 MV linac and resultant heterogeneity induced within the 30 cm diameter of spherical volume (DSV) of a novel 1 Tesla split bore MRI magnet. A number of different shield parameters were investigated; distance between shield and magnet, shield shape, shield thickness, shield length, openings in the shield, number of concentric layers, spacing between each layer, and shield material. Both the in-line and perpendicular MRI-Linac configurations were studied. By modifying the shield shape around the linac from the starting design of an open ended cylinder, the shielding effect was boosted by approximately 70% whilst the impact on the magnet was simultaneously reduced by approximately 10%. Openings in the shield for the RF port and beam exit were substantial sources of field leakage; however it was demonstrated that shielding could be added around these openings to compensate for this leakage. Layering multiple concentric shield shells was highly effective in the perpendicular configuration, but less so for the in-line configuration. Cautious use of high permeability materials such as Mu-metal can greatly increase the shielding performance in some scenarios. In the perpendicular configuration, magnetic shielding was more effective and the impact on the magnet lower compared with the in-line configuration.

  18. Fetal central nervous system anomalies: fast MRI vs ultrasonography

    International Nuclear Information System (INIS)

    Yang Wenzhong; Xia Liming; Yang Minjie; Feng Dingyi; Hu Junwu; Zou Mingli; Wang Chengyuan; Chen Xinlin; Yang Xiaohong

    2006-01-01

    Objective: To evaluate the ability of fast MRI to detect fetal central nervous system (CNS) anomalies and to compare its performance with that of prenatal ultrasonography (US). Methods Forty-eight pregnant women were detected by conventional prenatal US and MRI. Twenty-two fetuses with CNS anomalies were conformed by autopsy and follow-up. The MR and US appearances of fetal CNS structure were compared to each other and to that of autopsy. Results: A total of 26 CNS anomalies were identified by autopsy (n=17) and follow-up (n=9) including anencephaly (n=6), rachischisis (n=2), encephalocele (n=3), congenital hydrocephalus (n=7), alobar holoprosencephaly (n=1), porencephalia (n=3), arachnoid cyst (n=2) and choroids plexus cyst (n=2). US diagnosed 24 CNS anomalies, the correct diagnostic rate was 92.3%, the false-positive rate was 3.8%, the missed-diagnostic rate was 3.8%. MRI diagnosed 23 CNS anomalies, the correct-diagnostic rate was 88.5%, the false-positive rate was 3.8% ,the missed-diagnostic rate was 7.7%. There was no difference between US and MRI (P>0.05), but MRI have larger FOV, higher tissues resolution, and can demonstrate gray-white matter in detail. Conclusions: MR imaging has a similar sensitivity to that of US in the detection of fetal CNS anomalies. (authors)

  19. Flexible energy systems

    DEFF Research Database (Denmark)

    Lund, Henrik

    2003-01-01

    The paper discusses and analyses diffent national strategies and points out key changes in the energy system in order to achieve a system which can benefit from a high percentage of wind and CHP without having surplus production problems, introduced here as a flexible energy system....

  20. An MRI-compatible hand sensory vibrotactile system

    International Nuclear Information System (INIS)

    Wang, Fa; Lakshminarayanan, Kishor; Slota, Gregory P; Seo, Na Jin; Webster, John G

    2015-01-01

    Recently, the application of vibrotactile noise to the wrist or back of the hand has been shown to enhance fingertip tactile sensory perception (Enders et al 2013), supporting the potential for an assistive device worn at the wrist, that generates minute vibrations to help the elderly or patients with sensory deficit. However, knowledge regarding the detailed physiological mechanism behind this sensory improvement in the central nervous system, especially in the human brain, is limited, hindering progress in development and use of such assistive devices. To enable investigation of the impact of vibrotactile noise on sensorimotor brain activity in humans, a magnetic resonance imaging (MRI)-compatible vibrotactile system was developed to provide vibrotactile noise during an MRI of the brain. The vibrotactile system utilizes a remote (outside the MR room) signal amplifier which provides a voltage from –40 to +40 V to drive a 12 mm diameter piezoelectric vibrator (inside the MR room). It is portable and is found to be MRI-compatible which enables its use for neurologic investigation with MRI. The system was also found to induce an improvement in fingertip tactile sensation, consistent with the previous study. (note)

  1. LCA of Energy Systems

    DEFF Research Database (Denmark)

    Laurent, Alexis; Espinosa Martinez, Nieves; Hauschild, Michael Zwicky

    2018-01-01

    Energy systems are essential in the support of modern societies’ activities, and can span a wide spectrum of electricity and heat generation systems and cooling systems. Along with their central role and large diversity, these systems have been demonstrated to cause serious impacts on human health...... , ecosystems and natural resources. Over the past two decades, energy systems have thus been the focus of more than 1000 LCA studies, with the aim to identify and reduce these impacts. This chapter addresses LCA applications to energy systems for generation of electricity and heat . The chapter gives insight...

  2. Advanced energy conversion & mechatronics systems

    NARCIS (Netherlands)

    Lomonova, E.A.

    2015-01-01

    Ultra-high precision systems are encountered in high-tech industrial applications including semiconductor lithography equipment, pick-and-place machines for the manufacturing of electronic components, microsurgery equipment, MRI equipment and calibration devices in electron microscopes. The

  3. Ultra-low field MRI food inspection system prototype

    Energy Technology Data Exchange (ETDEWEB)

    Kawagoe, Satoshi, E-mail: s133413@edu.tut.ac.jp; Toyota, Hirotomo; Hatta, Junichi; Ariyoshi, Seiichiro; Tanaka, Saburo, E-mail: tanakas@ens.tut.ac.jp

    2016-11-15

    Highlights: • We have developed a ULF-MRI system using HTS-SQUID for food inspection. • We developed a compact magnetically shielded box to attenuate environmental noise. • The 2D-MR image was reconstructed from the grid processing data using 2D-FFT method. • The 2D-MR images of a disk-shaped and a multiple cell water sample were obtained. • The results showed the possibility of applying the ULF-MRI system to food inspection. - Abstract: We develop an ultra-low field (ULF) magnetic resonance imaging (MRI) system using a high-temperature superconducting quantum interference device (HTS-SQUID) for food inspection. A two-dimensional (2D)-MR image is reconstructed from the grid processing raw data using the 2D fast Fourier transform method. In a previous study, we combined an LC resonator with the ULF-MRI system to improve the detection area of the HTS-SQUID. The sensitivity was improved, but since the experiments were performed in a semi-open magnetically shielded room (MSR), external noise was a problem. In this study, we develop a compact magnetically shielded box (CMSB), which has a small open window for transfer of a pre-polarized sample. Experiments were performed in the CMSB and 2D-MR images were compared with images taken in the semi-open MSR. A clear image of a disk-shaped water sample is obtained, with an outer dimension closer to that of the real sample than in the image taken in the semi-open MSR. Furthermore, the 2D-MR image of a multiple cell water sample is clearly reconstructed. These results show the applicability of the ULF-MRI system in food inspection.

  4. Renewable Energy Tracking Systems

    Science.gov (United States)

    Renewable energy generation ownership can be accounted through tracking systems. Tracking systems are highly automated, contain specific information about each MWh, and are accessible over the internet to market participants.

  5. New secondary energy systems

    International Nuclear Information System (INIS)

    Schulten, R.

    1977-01-01

    As an introduction, the FRG's energy industry situation is described, secondary energy systems to be taken into consideration are classified, and appropriate market requirements are analyzed. Dealt with is district heating, i.e. the direct transport of heat by means of circulating media, and long-distance energy, i.e. the long-distance energy transport by means of chemical conversion in closed- or open-cycle systems. In closed-cycle systems heat is transported in the form of chemical latent energy. In contrast to this, chemical energy is transported in open-cycle systems in the form of fuel gases produced by coal gasification or by thermochemical water splitting. (GG) [de

  6. Energy Systems Integration Facility News | Energy Systems Integration

    Science.gov (United States)

    Facility | NREL Energy Systems Integration Facility News Energy Systems Integration Facility Energy Dataset A massive amount of wind data was recently made accessible online, greatly expanding the Energy's National Renewable Energy Laboratory (NREL) has completed technology validation testing for Go

  7. Small Wind Energy Systems

    DEFF Research Database (Denmark)

    Simões, Marcelo Godoy; Farret, Felix Alberto; Blaabjerg, Frede

    2017-01-01

    considered when selecting a generator for a wind power plant, including capacity of the AC system, types of loads, availability of spare parts, voltage regulation, technical personal and cost. If several loads are likely inductive, such asphase-controlled converters, motors and fluorescent lights......This chapter intends to serve as a brief guide when someone is considering the use of wind energy for small power applications. It is discussed that small wind energy systems act as the major energy source for residential or commercial applications, or how to make it part of a microgrid...... as a distributed generator. In this way, sources and loads are connected in such a way to behave as a renewable dispatch center. With this regard, non-critical loads might be curtailed or shed during times of energy shortfall or periods of high costs of energy production. If such a wind energy system is connected...

  8. Smart energy management system

    Science.gov (United States)

    Desai, Aniruddha; Singh, Jugdutt

    2010-04-01

    Peak and average energy usage in domestic and industrial environments is growing rapidly and absence of detailed energy consumption metrics is making systematic reduction of energy usage very difficult. Smart energy management system aims at providing a cost-effective solution for managing soaring energy consumption and its impact on green house gas emissions and climate change. The solution is based on seamless integration of existing wired and wireless communication technologies combined with smart context-aware software which offers a complete solution for automation of energy measurement and device control. The persuasive software presents users with easy-to-assimilate visual cues identifying problem areas and time periods and encourages a behavioural change to conserve energy. The system allows analysis of real-time/statistical consumption data with the ability to drill down into detailed analysis of power consumption, CO2 emissions and cost. The system generates intelligent projections and suggests potential methods (e.g. reducing standby, tuning heating/cooling temperature, etc.) of reducing energy consumption. The user interface is accessible using web enabled devices such as PDAs, PCs, etc. or using SMS, email, and instant messaging. Successful real-world trial of the system has demonstrated the potential to save 20 to 30% energy consumption on an average. Low cost of deployment and the ability to easily manage consumption from various web enabled devices offers gives this system a high penetration and impact capability offering a sustainable solution to act on climate change today.

  9. What Is Energy Systems Integration? | Energy Systems Integration Facility |

    Science.gov (United States)

    NREL What Is Energy Systems Integration? What Is Energy Systems Integration? Energy systems integration (ESI) is an approach to solving big energy challenges that explores ways for energy systems to Research Community NREL is a founding member of the International Institute for Energy Systems Integration

  10. Fetal MRI of the urinary system

    International Nuclear Information System (INIS)

    Hoermann, Marcus; Brugger, Peter C.; Balassy, Csilla; Witzani, Linde; Prayer, Daniela

    2006-01-01

    The assessment of the urinary system is typically performed by ultrasound. Nevertheless, an ultrasound may be inconclusive in fetuses with renal diseases that result in anhydramnios or oligohydramnios. In such cases, and in other cases in which ultrasound is limited, further investigation with MR should be considered. In the following article, we will provide an overview of the most commonly encountered disorders of the urinary system and their appearance on fetal MR imaging. Fetal MR imaging can accurately diagnose a wide variety of urinary tract disorders and must be seen as a valuable complementary tool to ultrasound in the assessment of the urinary system, particularly in cases of inconclusive ultrasound findings

  11. Fetal MRI of the urinary system

    Energy Technology Data Exchange (ETDEWEB)

    Hoermann, Marcus [Department of Radiodiagnostics, Medical University of Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria)]. E-mail: marcus.hoermann@meduniwien.ac.at; Brugger, Peter C. [Center of Anatomy and Cell Biology, Medical University of Vienna (Austria); Balassy, Csilla [Department of Radiodiagnostics, Medical University of Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria); Witzani, Linde [Department of Radiodiagnostics, Medical University of Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria); Prayer, Daniela [Department of Radiodiagnostics, Medical University of Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria)

    2006-02-15

    The assessment of the urinary system is typically performed by ultrasound. Nevertheless, an ultrasound may be inconclusive in fetuses with renal diseases that result in anhydramnios or oligohydramnios. In such cases, and in other cases in which ultrasound is limited, further investigation with MR should be considered. In the following article, we will provide an overview of the most commonly encountered disorders of the urinary system and their appearance on fetal MR imaging. Fetal MR imaging can accurately diagnose a wide variety of urinary tract disorders and must be seen as a valuable complementary tool to ultrasound in the assessment of the urinary system, particularly in cases of inconclusive ultrasound findings.

  12. Energy production systems engineering

    CERN Document Server

    Blair, Thomas Howard

    2017-01-01

    Energy Production Systems Engineering presents IEEE, Electrical Apparatus Service Association (EASA), and International Electrotechnical Commission (IEC) standards of engineering systems and equipment in utility electric generation stations. Electrical engineers that practice in the energy industry must understand the specific characteristics of electrical and mechanical equipment commonly applied to energy production and conversion processes, including the mechanical and chemical processes involved, in order to design, operate and maintain electrical systems that support and enable these processes. To aid this understanding, Energy Production Systems Engineeringdescribes the equipment and systems found in various types of utility electric generation stations. This information is accompanied by examples and practice problems. It also addresses common issues of electrical safety that arise in electric generation stations.

  13. Energy efficiency system development

    Science.gov (United States)

    Leman, A. M.; Rahman, K. A.; Chong, Haw Jie; Salleh, Mohd Najib Mohd; Yusof, M. Z. M.

    2017-09-01

    By subjecting to the massive usage of electrical energy in Malaysia, energy efficiency is now one of the key areas of focus in climate change mitigation. This paper focuses on the development of an energy efficiency system of household electrical appliances for residential areas. Distribution of Questionnaires and pay a visit to few selected residential areas are conducted during the fulfilment of the project as well as some advice on how to save energy are shared with the participants. Based on the collected data, the system developed by the UTHM Energy Team is then evaluated from the aspect of the consumers' behaviour in using electrical appliances and the potential reduction targeted by the team. By the end of the project, 60% of the participants had successfully reduced the electrical power consumption set by the UTHM Energy Team. The reasons for whether the success and the failure is further analysed in this project.

  14. Energy Usage Analysis System

    Data.gov (United States)

    General Services Administration — The EUAS application is a web based system which serves Energy Center of Expertise, under the Office of Facilitates Management and Service Programs. EUAS is used for...

  15. Flow energy conversion system

    International Nuclear Information System (INIS)

    Sargsyan, R.A.

    2011-01-01

    A cost-effective hydropower system called here Flow Energy Converter was developed, patented, manufactured and tested for water pumping, electricity generation and other purposes especially useful for the rural communities. The system consists of water-driven turbine with plane-surface blades, power transmission means and pump and/or generator. Working sample of the Flow Energy Converter was designed and manufactured at the Institute of Radio Physics and Electronics

  16. Solar Energy Systems

    Science.gov (United States)

    1984-01-01

    Calibrated in kilowatt hours per square meter, the solar counter produced by Dodge Products, Inc. provides a numerical count of the solar energy that has accumulated on a surface. Solar energy sensing, measuring and recording devices in corporate solar cell technology developed by Lewis Research Center. Customers for their various devices include architects, engineers and others engaged in construction and operation of solar energy facilities; manufacturers of solar systems or solar related products, such as glare reducing windows; and solar energy planners in federal and state government agencies.

  17. Living Systems Energy Module

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-26

    The Living Systems Energy Module, renamed Voyage from the Sun, is a twenty-lesson curriculum designed to introduce students to the major ways in which energy is important in living systems. Voyage from the Sun tells the story of energy, describing its solar origins, how it is incorporated into living terrestrial systems through photosynthesis, how it flows from plants to herbivorous animals, and from herbivores to carnivores. A significant part of the unit is devoted to examining how humans use energy, and how human impact on natural habitats affects ecosystems. As students proceed through the unit, they read chapters of Voyage from the Sun, a comic book that describes the flow of energy in story form (Appendix A). During the course of the unit, an ``Energy Pyramid`` is erected in the classroom. This three-dimensional structure serves as a classroom exhibit, reminding students daily of the importance of energy and of the fragile nature of our living planet. Interactive activities teach students about adaptations that allow plants and animals to acquire, to use and to conserve energy. A complete list of curricular materials and copies of all activity sheets appear in Appendix B.

  18. Small Wind Energy Systems

    DEFF Research Database (Denmark)

    Simoes, Marcelo; Farret, Felix Alberto; Blaabjerg, Frede

    2015-01-01

    devices, and a centralized distribution control. In order to establish a small wind energy system it is important to observe the following: (i) Attending the energy requirements of the actual or future consumers; (ii) Establishing civil liabilities in case of accidents and financial losses due to shortage...... or low quality of energy; (iii) Negotiating collective conditions to interconnect the microgrid with the public network or with other sources of energy that is independent of wind resources; (iv) Establishing a performance criteria of power quality and reliability to end-users, in order to reduce costs...... and guaranteeing an acceptable energy supply. This paper discuss how performance is affected by local conditions and random nature of the wind, power demand profiles, turbine related factors, and presents the technical issues for implementing a self-excited induction generator system, or a permanent magnet based...

  19. Alternative Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    West, M.; Duckers, L.; Lockett, P.; Loughridge, B.; Peatfield, T.; White, P.

    1984-01-01

    The Coventry (Lanchester) Polytechnic Wave Energy Group has been involved in the United Kingdom wave energy research programme since its inception in 1975. Whilst the work of the group is mainly concerned with wave energy, and currently is directed towards the design of a wave energy device tailored to the needs of isolated/island communities, it has some involvement with other aspects of the alternatives. This conference, dealing with alternative energy systems and their electrical integration and utilisation was engendered by the general interest which the Polytechnic group members have in the alternatives and their use. The scope for electrical integration and utilisation is very broad. Energy for family groups may be provided in a relatively unsophisticated way which is acceptable to them. Small population centres, for example island communities relying upon diesel equipment, can reap the benefits of the alternatives through their ability to accept novel integration schemes and a flexible approach to the use of the energy available. Consumers already enjoying the benefits of a 'firm' electricity grid supply can use energy from a variety of alternative systems, via the grid, without having to modify their energy consumption habits. In addition to the domestic and industrial applications and coastal possibilities, specialist applications in isolated environments have also emerged. The Proceedings detail practical, technical and economic aspects of the alternatives and their electrical integration and utilisation.

  20. Development of an Optical Fiber-Based MR Compatible Gamma Camera for SPECT/MRI Systems

    Science.gov (United States)

    Yamamoto, Seiichi; Watabe, Tadashi; Kanai, Yasukazu; Watabe, Hiroshi; Hatazawa, Jun

    2015-02-01

    Optical fiber is a promising material for integrated positron emission tomography (PET) and magnetic resonance imaging (MRI) PET/MRI systems. Because its material is plastic, it has no interference between MRI. However, it is unclear whether this material can also be used for a single photon emission tomography (SPECT)/MRI system. For this purpose, we developed an optical fiber-based block detector for a SPECT/MRI system and tested its performance by combining 1.2 ×1.2 ×6 mm Y2SiO5 (YSO) pixels into a 15 ×15 block and was coupled it to an optical fiber image guide that used was 0.5-mm in diameter with 80-cm long double clad fibers. The image guide had 22 ×22 mm rectangular input and an equal size output. The input of the optical fiber-based image guide was bent at 90 degrees, and the output was optically coupled to a 1-in square high quantum efficiency position sensitive photomultiplier tube (HQE-PSPMT). The parallel hole, 7-mm-thick collimator made of tungsten plastic was mounted on a YSO block. The diameter of the collimator holes was 0.8 mm which was positioned one-to-one coupled to the YSO pixels. We evaluated the intrinsic and system performances. We resolved most of the YSO pixels in a two-dimensional histogram for Co-57 gamma photons (122-keV) with an average peak-to-value ratio of 1.5. The energy resolution was 38% full-width at half-maximum (FWHM). The system resolution was 1.7-mm FWHM, 1.5 mm from the collimator surface, and the sensitivity was 0.06%. Images of a Co-57 point source could be successfully obtained inside 0.3 T MRI without serious interference. We conclude that the developed optical fiber-based YSO block detector is promising for SPECT/MRI systems.

  1. Simulation of spin dynamics: a tool in MRI system development

    International Nuclear Information System (INIS)

    Stoecker, Tony; Vahedipour, Kaveh; Shah, N Jon

    2011-01-01

    Magnetic Resonance Imaging (MRI) is a routine diagnostic tool in the clinics and the method of choice in soft-tissue contrast medical imaging. It is an important tool in neuroscience to investigate structure and function of the living brain on a systemic level. The latter is one of the driving forces to further develop MRI technology, as neuroscience especially demands higher spatiotemporal resolution which is to be achieved through increasing the static main magnetic field, B 0 . Although standard MRI is a mature technology, ultra high field (UHF) systems, at B 0 ≥ 7 T, offer space for new technical inventions as the physical conditions dramatically change. This work shows that the development strongly benefits from computer simulations of the measurement process on the basis of a semi-classical, nuclear spin-1/2 treatment given by the Bloch equations. Possible applications of such simulations are outlined, suggesting new solutions to the UHF-specific inhomogeneity problems of the static main field as well as the high-frequency transmit field.

  2. Energy saving synergies in national energy systems

    DEFF Research Database (Denmark)

    Thellufsen, Jakob Zinck; Lund, Henrik

    2015-01-01

    In the transition towards a 100% renewable energy system, energy savings are essential. The possibility of energy savings through conservation or efficiency increases can be identified in, for instance, the heating and electricity sectors, in industry, and in transport. Several studies point...... to various optimal levels of savings in the different sectors of the energy system. However, these studies do not investigate the idea of energy savings being system dependent. This paper argues that such system dependency is critical to understand, as it does not make sense to analyse an energy saving...... without taking into account the actual benefit of the saving in relation to the energy system. The study therefore identifies a need to understand how saving methods may interact with each other and the system in which they are conducted. By using energy system analysis to do hourly simulation...

  3. Electrical energy systems

    CERN Document Server

    El-Hawary, Mohamed E

    2007-01-01

    Features discussions ranging from the technical aspects of generation, transmission, distribution, and utilization to power system components, theory, protection, and the energy control center that offer an introduction to effects of deregulating electric power systems, blackouts and their causes, and minimizing their effects.

  4. The Smart Energy System

    DEFF Research Database (Denmark)

    Jurowetzki, Roman; Dyrelund, Anders; Hummelmose, Lars

    Copenhagen Cleantech Cluster has launched a new report, which provides an overview of Danish competencies relating to smart energy systems. The report, which is based on a questionnaire answered by almost 200 companies working with smart energy as well as a number of expert interviews, focuses on...... production, large scale solar heat, fuel cells, heat storage, waste incineration, among others, the report draws a picture of Denmark as a research and development hub for smart energy system solutions.......Copenhagen Cleantech Cluster has launched a new report, which provides an overview of Danish competencies relating to smart energy systems. The report, which is based on a questionnaire answered by almost 200 companies working with smart energy as well as a number of expert interviews, focuses...... on the synergies which are obtained through integration of the district heating and district cooling, gas, and electricity grid into a single smart energy system. Besides documenting the technology and innovation strengths that Danish companies possess particularly relating to wind, district heating, CHP...

  5. Precise fusion of MRI and dual energy 111In WBC/99mTc HDP SPECT/CT in the diabetic foot using companion CT: an example of SPECT/MRI imaging

    International Nuclear Information System (INIS)

    Knešaurek, K.; Heiba, S.; Kolker, D.; Vatti, S.

    2015-01-01

    The purpose of our study was to correctly fuse MRI and SPECT 111 In WBC and 99m Tc HDP images using companion CT images. The fused images could be used to assess proper surgical approach in treatment of the diabetic foot. Nine patients who had dual energy 111 In WBC/ 99 m Tc HDP SPECT/CT and MRI studies within a week were investigated in an ongoing project. A GE Infinia SPECT/CT camera and Siemens MAGNETOM 1.5T MR system were used in this study. First, the MRI and corresponding CT images were coregistrated using a transformation based on normalized mutual information. The transformation was saved and used for MRI and 111 In WBC/ 99 m Tc HDP SPECT fusion. A Jaszczak phantom study was also performed in order to estimate accuracy of MRI/ SPECT fusion. The Jaszczak phantom study with 3.7 MBq 111 In hot sphere showed that MRI/SPECT alignment using the approach described above produced registration with 0.7±0.4 mm accuracy in all three dimensions (3D). The nine clinical cases were visually evaluated and showed 1-2 mm 3D fusion accuracy. MRI provides almost perfect anatomy of soft tissue and bony structures but it may exaggerate the extent of infection. 111 In WBC/ 99 m Tc HDP SPECT imaging is more accurate for infection detection but lacks anatomical reference. Combination of these images proved an essential adjunct to diagnosis. A clinical utility of the approach is illustrated in two clinical examples. In conclusion, the CT in dual energy 111 In WBC/ 99 m Tc HDP SPECT/CT studies can be used to accurately fuse and compare 111 In WBC/ 99 m Tc HDP SPECT and MRI images of the diabetic foot. This can significantly help in conservative treatment planning and limb salvage procedures in treatment of diabetic foot infections.

  6. MRI findings of central nervous system granulocytic sarcoma (chloroma)

    International Nuclear Information System (INIS)

    Lee, Chang Man; Kim, Myung Soon; Kim, Ik Soo; Cho, Kwan Soo

    1997-01-01

    To characterize MRI findings of central nervous system (CNS) granulocytic sarcoma (chloroma) and to analyse the points which differentiate it from other CNS tumors. We evaluated MRI in six patients with CNS granulocytic sarcoma proven by surgery or bone marrow biopsy (intracranical, one case and spine five cases). A 0.5T superconductive MR machine was used for diagnosis and, axial, coronal and sagittal T1- and T2-weighted spin echo images and Gd-DTPA enhanced T1-weighted images were obtained. We retrospectively analized the location, signal intensity, margin, contrast enhancement and homogeneity, and bony change around the tumor. MRI findings of CNS granulocytic sarcomas were as follows : one tumor was seen to be an extra-axial mass in the posterior fossa of the brain, four were epidural, and one was an epidural and presacral masses in the spine;tumor magins were lobulated and three were smooth. On T1-weighted images, all tumors were of isoignal intensity;on T2-weighted images, four were of isosignal intersity and two were of high signal intensity. Contrast enhancement was inhomogeneous in five of six cases. Bony change around the tumor was seen in two cases. On T1-weighted images, CNS granulocytic sarcomas (chloromas) were of isosignal intensity, relative to brain parenchyma or spinal cord;on T2-weighted images, they were of iso or high signal intensity, with relative contrast enhancement. These points could be useful in differentiating them from other CNS tumors

  7. Understanding renewable energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Quaschning, Volker

    2005-01-15

    Beginning with an overview of renewable energy sources including biomass, hydroelectricity, geothermal, tidal, wind and solar power, this book explores the fundamentals of different renewable energy systems. The main focus is on technologies with high development potential such as solar thermal systems, photovoltaics and wind power. This text not only describes technological aspects, but also deals consciously with problems of the energy industry. In this way, the topics are treated in a holistic manner, bringing together maths, engineering, climate studies and economics, and enabling readers to gain a broad understanding of renewable energy technologies and their potential. The book also contains a free CD-ROM resource, which includes a variety of specialist simulation software and detailed figures from the book. (Author)

  8. Clinical and MRI correlation in multiple system atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Negoro, Kiyoshi; Morimatsu, Mitsunori (Yamaguchi Univ., Ube (Japan). School of Medicine)

    1994-05-01

    By using magnetic resonance imaging (MRI), we studied 11 patients with multiple system atrophy (MSA): 5 olivo-pontocerebellar atrophy (OPCA), 2 Shy-Drager syndrome (SDS), and 4 striatonigral degeneration (SND). The diagnoses of OPCA, SDS and SND were clinically made. The MR images were performed on 1.5 tesla MRI unit (Siemens Asahi Medical, Magnetom H15), using a T[sub 2]-weighted spin echo (SE) sequence (TR: 2000-3000 ms, TE: 80-90 ms), a T[sub 1]-weighted SE sequence (TR: 550, TE: 15), and a proton density-weighted (PD) SE sequence (TR: 2000-3000, TE: 12-22). In the patients with OPCA, MRI revealed cerebellar and brainstem atrophy and degeneration of pontine transverse fibers more marked than in the patients with SDS and SND. T[sub 2]-weighted images showed low intensity in posterolateral putamina in one OPCA patient and all of SDS and SND patients. PD images demonstrated the abnormal slit-like high signals in posterolateral putamina in three SND. The degree of cerebellar ataxia was not well correlated with cerebellar and brainstem atrophy and degeneration of pontine transverse fibers. There was a positive correlation between the atrophy of cerebellum and brainstem and the duration of cerebellar ataxia. In most of the patients with Parkinsonism, MRI demonstrated abnormal low signals in putamina on T[sub 2]-weighted images. There were positive correlations between the abnormal low signals putamina and the duration and severity of Parkinsonism. Though abnormal low signals in lateral putamina may be seen in normal aging and other disorders on T[sub 2]-weighted images, it is useful to evaluate Parkinsonism in MSA. We believe that the abnormal slit-like high signals in posterolateral putamina in MSA may suggest loss of neurons and gliosis. (author).

  9. Robotic System for MRI-Guided Stereotactic Neurosurgery

    Science.gov (United States)

    Li, Gang; Cole, Gregory A.; Shang, Weijian; Harrington, Kevin; Camilo, Alex; Pilitsis, Julie G.; Fischer, Gregory S.

    2015-01-01

    Stereotaxy is a neurosurgical technique that can take several hours to reach a specific target, typically utilizing a mechanical frame and guided by preoperative imaging. An error in any one of the numerous steps or deviations of the target anatomy from the preoperative plan such as brain shift (up to 20 mm), may affect the targeting accuracy and thus the treatment effectiveness. Moreover, because the procedure is typically performed through a small burr hole opening in the skull that prevents tissue visualization, the intervention is basically “blind” for the operator with limited means of intraoperative confirmation that may result in reduced accuracy and safety. The presented system is intended to address the clinical needs for enhanced efficiency, accuracy, and safety of image-guided stereotactic neurosurgery for Deep Brain Stimulation (DBS) lead placement. The work describes a magnetic resonance imaging (MRI)-guided, robotically actuated stereotactic neural intervention system for deep brain stimulation procedure, which offers the potential of reducing procedure duration while improving targeting accuracy and enhancing safety. This is achieved through simultaneous robotic manipulation of the instrument and interactively updated in situ MRI guidance that enables visualization of the anatomy and interventional instrument. During simultaneous actuation and imaging, the system has demonstrated less than 15% signal-to-noise ratio (SNR) variation and less than 0.20% geometric distortion artifact without affecting the imaging usability to visualize and guide the procedure. Optical tracking and MRI phantom experiments streamline the clinical workflow of the prototype system, corroborating targeting accuracy with 3-axis root mean square error 1.38 ± 0.45 mm in tip position and 2.03 ± 0.58° in insertion angle. PMID:25376035

  10. Evolving energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Mills, E.

    1991-04-01

    This thesis presents scenarios of future energy systems, a cost-benefit analysis of measures to avoid greenhouse-gas emissions, an analysis of the effect of energy prices on end-use efficiencies and fuel choices, and an evaluation of financial-incentive programs designed to induce investments in efficient energy use. Twelve integrated energy supply/demand scenarios for the Swedish heat-and-power sector are presented to illustrate the potential for improvements in end-use efficiency and increased utilization of renewable energy sources. The results show that greenhouse-gas emissions could be reduced by 35 per cent from 1987 levels by 2010, with a net economic benefit compared to a business-as-usual scenario. A generalized methodology for calculating the net costs of reducing greenhouse-gas emissions is applied to a variety of fuel choices and energy end-use technologies. A key finding is that a combination of increased end-use efficiencies and use of renewable energy systems is required to achieve maximum cost-effective emissions reductions. End-use efficiencies and inter-fuel competition in Denmark and Sweden are compared during a time period in which real electricity prices were declining in Sweden and increasing in Denmark. Despite these different price environments, efficiencies and choices of heating fuels did not generally develop as expected according to economic theory. The influences of counter-price and non-price factors are important in understanding this outcome. Relying on prices alone injects considerable uncertainty into the energy planning process, and precludes efficiency improvements and fuel choices attainable with other mechanisms. Incentive programs can be used to promote energy-efficient technologies. Utilities in Europe have recently offered financial incentives intended to stimulate the adoption of compact-fluorescent lamps. These programs have been cost-effective in comparison to new electric supply. (au).

  11. Analysis of systemic lupus erythematosus (SLE) involving the central nervous system by magnetic resonance imaging (MRI)

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Kimihiro; Hara, Masako; Nakajima, Shinji and others

    1989-04-01

    Involvement of the central nervous system (CNS) commonly occurs in systemic lupus erythematosus (SLE). But definitive diagnosis remains difficult even with computed tomography (CT). In this study, we used the recently developed technique, magnetic resonance imaging (MRI) for CNS lupus and compared it with CT scans. CT was performed with a General Electric 8800 CT/T scanner. MRI was performed using a Mitsubishi Electric MMI-150 S. Ten patients with CNS lupus were divided into 3 groups. Group I included 4 cases with neurological manifestations alone. All lesions seen on CT were also detected by MRI, with greater clarity and extent. Furthermore, MRI depicted several microinfarcts in white matter without symptoms. Group II included 5 cases with psychiatric features alone. MRI detected a thalamic microinfarct in only one case while CT showed no abnormality in all cases. Group III included 1 case with both neurological and psychiatric symptoms. MRI demonstrated a small infarct of midbrain corresponding with neurological symptoms, more clearly than CT. Therefore MRI demonstrates the degree of brain involvement in SLE more accurately than CT. (author).

  12. Analysis of systemic lupus erythematosus (SLE) involving the central nervous system by magnetic resonance imaging (MRI)

    International Nuclear Information System (INIS)

    Suzuki, Kimihiro; Hara, Masako; Nakajima, Shinji

    1989-01-01

    Involvement of the central nervous system (CNS) commonly occurs in systemic lupus erythematosus (SLE). But definitive diagnosis remains difficult even with computed tomography (CT). In this study, we used the recently developed technique, magnetic resonance imaging (MRI) for CNS lupus and compared it with CT scans. CT was performed with a General Electric 8800 CT/T scanner. MRI was performed using a Mitsubishi Electric MMI-150 S. Ten patients with CNS lupus were divided into 3 groups. Group I included 4 cases with neurological manifestations alone. All lesions seen on CT were also detected by MRI, with greater clarity and extent. Furthermore, MRI depicted several microinfarcts in white matter without symptoms. Group II included 5 cases with psychiatric features alone. MRI detected a thalamic microinfarct in only one case while CT showed no abnormality in all cases. Group III included 1 case with both neurological and psychiatric symptoms. MRI demonstrated a small infarct of midbrain corresponding with neurological symptoms, more clearly than CT. Therefore MRI demonstrates the degree of brain involvement in SLE more accurately than CT. (author)

  13. Phased transducer array for acoustic energy harvesting inside an MRI machine

    NARCIS (Netherlands)

    Klymko, V.; Roes, M.G.L.; Duivenbode, van J.; Lomonova, E.

    2013-01-01

    In this study, an array of piezoelectric speakers is used to focus acoustic energy on a single transducer that acts as a harvester. The transmitting transducers are located along a curve that fits inside the magnetic resonance interferometer (MRI) torus interior. The numerical results for the

  14. Energy systems transformation.

    Science.gov (United States)

    Dangerman, A T C Jérôme; Schellnhuber, Hans Joachim

    2013-02-12

    The contemporary industrial metabolism is not sustainable. Critical problems arise at both the input and the output side of the complex: Although affordable fossil fuels and mineral resources are declining, the waste products of the current production and consumption schemes (especially CO(2) emissions, particulate air pollution, and radioactive residua) cause increasing environmental and social costs. Most challenges are associated with the incumbent energy economy that is unlikely to subsist. However, the crucial question is whether a swift transition to its sustainable alternative, based on renewable sources, can be achieved. The answer requires a deep analysis of the structural conditions responsible for the rigidity of the fossil-nuclear energy system. We argue that the resilience of the fossil-nuclear energy system results mainly from a dynamic lock-in pattern known in operations research as the "Success to the Successful" mode. The present way of generating, distributing, and consuming energy--the largest business on Earth--expands through a combination of factors such as the longevity of pertinent infrastructure, the information technology revolution, the growth of the global population, and even the recent financial crises: Renewable-energy industries evidently suffer more than the conventional-energy industries under recession conditions. Our study tries to elucidate the archetypical traits of the lock-in pattern and to assess the respective importance of the factors involved. In particular, we identify modern corporate law as a crucial system element that thus far has been largely ignored. Our analysis indicates that the rigidity of the existing energy economy would be reduced considerably by the assignment of unlimited liabilities to the shareholders.

  15. Wind Energy Systems.

    Science.gov (United States)

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    During the 1920s and 1930s, millions of wind energy systems were used on farms and other locations far from utility lines. However, with passage of the Rural Electrification Act in 1939, cheap electricity was brought to rural areas. After that, the use of wind machines dramatically declined. Recently, the rapid rise in fuel prices has led to a…

  16. Energy Systems Integration Facility Videos | Energy Systems Integration

    Science.gov (United States)

    Facility | NREL Energy Systems Integration Facility Videos Energy Systems Integration Facility Integration Facility NREL + SolarCity: Maximizing Solar Power on Electrical Grids Redefining What's Possible for Renewable Energy: Grid Integration Robot-Powered Reliability Testing at NREL's ESIF Microgrid

  17. Energy Systems Integration Laboratory | Energy Systems Integration Facility

    Science.gov (United States)

    | NREL Integration Laboratory Energy Systems Integration Laboratory Research in the Energy Systems Integration Laboratory is advancing engineering knowledge and market deployment of hydrogen technologies. Applications include microgrids, energy storage for renewables integration, and home- and station

  18. Proof-of-principle study of a small animal PET/field-cycled MRI combined system using conventional PMT technology

    International Nuclear Information System (INIS)

    Peng Hao; Handler, William B.; Scholl, Timothy J.; Simpson, P.J.; Chronik, Blaine A.

    2010-01-01

    There are currently several approaches to the development of combined PET/MRI systems, all of which need to address adverse interactions between the two systems. Of particular relevance to the majority of proposed PET/MRI systems is the effect that static and dynamic magnetic fields have on the performance of PET detection systems based on photomultiplier tubes (PMTs). In the work reported in this paper, performance of two conventional PMTs has been systematically investigated and characterized as a function of magnetic field exposure conditions. Detector gain, energy resolution, time resolution, and efficiency were measured for static field exposures between 0 and 6.3 mT. Additionally, the short-term recovery and long-term stability of gain and energy resolution were measured in the presence of repeatedly applied dynamic magnetic fields changing at 4 T/s. It was found that the detectors recovered normal operation within several milliseconds following the end of large pulsed magnetic fields. In addition, the repeated applications of large pulsed magnetic fields did not significantly affect detector stability. Based on these results, we implemented a proof-of-principle PET/field-cycled MRI (FCMRI) system for small animal imaging using commercial PMT-based PET detectors. The first PET images acquired within the PET/FCMRI system are presented. The image quality, in terms of spatial resolution, was compared between standalone PET and the PET/FCMRI system. Finally, the relevance of these results to various aspects of PET/MRI system design is discussed.

  19. Energy storage connection system

    Science.gov (United States)

    Benedict, Eric L.; Borland, Nicholas P.; Dale, Magdelena; Freeman, Belvin; Kite, Kim A.; Petter, Jeffrey K.; Taylor, Brendan F.

    2012-07-03

    A power system for connecting a variable voltage power source, such as a power controller, with a plurality of energy storage devices, at least two of which have a different initial voltage than the output voltage of the variable voltage power source. The power system includes a controller that increases the output voltage of the variable voltage power source. When such output voltage is substantially equal to the initial voltage of a first one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the first one of the energy storage devices. The controller then causes the output voltage of the variable voltage power source to continue increasing. When the output voltage is substantially equal to the initial voltage of a second one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the second one of the energy storage devices.

  20. Energy Storage System

    Science.gov (United States)

    1996-01-01

    SatCon Technology Corporation developed the drive train for use in the Chrysler Corporation's Patriot Mark II, which includes the Flywheel Energy Storage (FES) system. In Chrysler's experimental hybrid- electric car, the hybrid drive train uses an advanced turboalternator that generates electricity by burning a fuel; a powerful, compact electric motor; and a FES that eliminates the need for conventional batteries. The FES system incorporates technology SatCon developed in more than 30 projects with seven NASA centers, mostly for FES systems for spacecraft attitude control and momentum recovery. SatCon will continue to develop the technology with Westinghouse Electric Corporation.

  1. Energy Storage and Smart Energy Systems

    DEFF Research Database (Denmark)

    Lund, Henrik; Østergaard, Poul Alberg; Connolly, David

    2016-01-01

    It is often highlighted how the transition to renewable energy supply calls for significant electricity storage. However, one has to move beyond the electricity-only focus and take a holistic energy system view to identify optimal solutions for integrating renewable energy. In this paper......, an integrated cross-sector approach is used to determine the most efficient and least-cost storage options for the entire renewable energy system concluding that the best storage solutions cannot be found through analyses focusing on the individual sub-sectors. Electricity storage is not the optimum solution...... to integrate large inflows of fluctuating renewable energy, since more efficient and cheaper options can be found by integrating the electricity sector with other parts of the energy system and by this creating a Smart Energy System. Nevertheless, this does not imply that electricity storage should...

  2. Energy Storage and Smart Energy Systems

    Directory of Open Access Journals (Sweden)

    Poul Alberg Østergaard

    2016-12-01

    Full Text Available It is often highlighted how the transition to renewable energy supply calls for significant electricity storage. However, one has to move beyond the electricity-only focus and take a holistic energy system view to identify optimal solutions for integrating renewable energy. In this paper, an integrated cross-sector approach is used to determine the most efficient and least-cost storage options for the entire renewable energy system concluding that the best storage solutions cannot be found through analyses focusing on the individual sub-sectors. Electricity storage is not the optimum solution to integrate large inflows of fluctuating renewable energy, since more efficient and cheaper options can be found by integrating the electricity sector with other parts of the energy system and by this creating a Smart Energy System. Nevertheless, this does not imply that electricity storage should be disregarded but that it will be needed for other purposes in the future.

  3. Wind energy systems

    International Nuclear Information System (INIS)

    Richardson, R.D.; McNerney, G.M.

    1993-01-01

    Wind energy has matured to a level of development where it is ready to become a generally accepted utility generation technology. A brief discussion of this development is presented, and the operating and design principles are discussed. Alternative designs for wind turbines and the tradeoffs that must be considered are briefly compared. Development of a wind energy system and the impacts on the utility network including frequency stability, voltage stability, and power quality are discussed. The assessment of wind power station economics and the key economic factors that determine the economic viability of a wind power plant are presented

  4. Value of prenatal MRI in early evaluation of fetal central nervous system anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Keiichi [Kugayama Hospital, Tokyo (Japan); Nakamura, Masanao; Hino, Ken [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine] [and others

    2002-08-01

    Advances in technology and the need for accurate prenatal diagnoses have produced great improvements in fetal diagnosis by MRI. However, there are still many problems with diagnosis of central nervous system (CNS) anomalies using MRI (e.g., time of diagnosis, factors limiting diagnostic ability. Fifteen cases referred to our clinic from 1992 to 2001 and examined using intrauterine ultrasound, prenatal MRI and postnatal MRI were reviewed retrospectively. All clinical records and findings from prenatal MRI, postnatal MRI and ultrasound were reviewed. Prenatal MRI was found to be equal in diagnostic power to ultrasound and postnatal MRI in 10 of the 15 cases. In the remaining 5 fetuses, the findings of prenatal MRI were not the same to those of prenatal ultrasound and postnatal MRI. Our goal was to determine the value of prenatal MRI in diagnosis of fetal CNS anomalies, to ascertain how this information might be used for counseling, and to assess its impact on pregnancy management. Prenatal MRI provided useful information for support personnel (e.g., physicians, nurses, caseworkers, religious advisers). (author)

  5. Energy Efficient Mobile Operating Systems

    OpenAIRE

    Muhammad Waseem

    2013-01-01

    Energy is an important resource in mobile computers now days. It is important to manage energy in efficient manner so that energy consumption will be reduced. Developers of operating system decided to increase the battery life time of mobile phones at operating system level. So, design of energy efficient mobile operating system is the best way to reduce the energy consumption in mobile devices. In this paper, currently used energy efficient mobile operating system is discussed and compared. ...

  6. Wellons Canada energy systems

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Wellons Canada is a British Columbia-based company that specializes in the manufacture and installation of lumber drying and energy conversion equipment. This brochure provided details of the Wellons energy system designed for oriented strand board (OSB) plants. The brochure outlined the system's scope of supply, and provided illustrations of system procedures from the initial wet fuel bin through to the electric precipitator used for air clean-up. During the process, fuel was conveyed from the bin to metering bins into combustors and through a cyclo-blast cell. Forced draft fan systems were then used to provide primary and secondary combustion air. Radiant heaters were then used. A drop-out chamber was supplied to allow for complete combustion of fuel particles and to provide a drop-out of ash. A fan was then used to deliver diluent air to maintain the set point temperature in the hot gas stream. Refractory lined hot gas ducts were used to deliver heat to the dryers. Hot gas was then drawn through a multi-cyclone collector for ash removal. Electrostatic precipitators were used to clean up emissions on a continuous operating basis. An automatic system was used to collect ash from the combustion system grates and other areas. Details of installation services provided by the company were also included. 42 figs.

  7. Wind energy conversion system

    Science.gov (United States)

    Longrigg, Paul

    1987-01-01

    The wind energy conversion system includes a wind machine having a propeller connected to a generator of electric power, the propeller rotating the generator in response to force of an incident wind. The generator converts the power of the wind to electric power for use by an electric load. Circuitry for varying the duty factor of the generator output power is connected between the generator and the load to thereby alter a loading of the generator and the propeller by the electric load. Wind speed is sensed electro-optically to provide data of wind speed upwind of the propeller, to thereby permit tip speed ratio circuitry to operate the power control circuitry and thereby optimize the tip speed ratio by varying the loading of the propeller. Accordingly, the efficiency of the wind energy conversion system is maximized.

  8. 21st Century's energy: Hydrogen energy system

    International Nuclear Information System (INIS)

    Veziroglu, T. Nejat; Sahin, Suemer

    2008-01-01

    Fossil fuels (i.e., petroleum, natural gas and coal), which meet most of the world's energy demand today, are being depleted fast. Also, their combustion products are causing the global problems, such as the greenhouse effect, ozone layer depletion, acid rains and pollution, which are posing great danger for our environment and eventually for the life in our planet. Many engineers and scientists agree that the solution to these global problems would be to replace the existing fossil fuel system by the hydrogen energy system. Hydrogen is a very efficient and clean fuel. Its combustion will produce no greenhouse gases, no ozone layer depleting chemicals, little or no acid rain ingredients and pollution. Hydrogen, produced from renewable energy (e.g., solar) sources, would result in a permanent energy system, which we would never have to change. However, there are other energy systems proposed for the post-petroleum era, such as a synthetic fossil fuel system. In this system, synthetic gasoline and synthetic natural gas will be produced using abundant deposits of coal. In a way, this will ensure the continuation of the present fossil fuel system. The two possible energy systems for the post-fossil fuel era (i.e., the solar-hydrogen energy system and the synthetic fossil fuel system) are compared with the present fossil fuel system by taking into consideration production costs, environmental damages and utilization efficiencies. The results indicate that the solar-hydrogen energy system is the best energy system to ascertain a sustainable future, and it should replace the fossil fuel system before the end of the 21st century

  9. 21st century's energy: hydrogen energy system

    International Nuclear Information System (INIS)

    Veziroglu, T. N.

    2007-01-01

    Fossil fuels (i.e., petroleum, natural gas and coal), which meet most of the world's energy demand today, are being depleted fast. Also, their combustion products are causing the global problems, such as the greenhouse effect, ozone layer depletion, acid rains and pollution, which are posing great danger for our environment and eventually for the life in our planet. Many engineers and scientists agree that the solution to these global problems would be to replace the existing fossil fuel system by the Hydrogen Energy System. Hydrogen is a very efficient and clean fuel. Its combustion will produce no greenhouse gases, no ozone layer depleting chemicals, little or no acid rain ingredients and pollution. Hydrogen, produced from renewable energy (e.g., solar) sources, would result in a permanent energy system, which we would never have to change. However, there are other energy systems proposed for the post-petroleum era, such as a synthetic fossil fuel system. In this system, synthetic gasoline and synthetic natural gas will be produced using abundant deposits of coal. In a way, this will ensure the continuation of the present fossil fuel system. The two possible energy systems for the post-fossil fuel era (i.e., the solar hydrogen energy system and the synthetic fossil fuel system) are compared with the present fossil fuel system by taking into consideration production costs, environmental damages and utilization efficiencies. The results indicate that the solar hydrogen energy system is the best energy system to ascertain a sustainable future, and it should replace the fossil fuel system before the end of the 21st Century

  10. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Steinbugler, M.; Dennis, E. [Princeton Univ., NJ (United States)] [and others

    1995-09-01

    For several years, researchers at Princeton University`s Center for Energy and Environmental Studies have carried out technical and economic assessments of hydrogen energy systems. Initially, we focussed on the long term potential of renewable hydrogen. More recently we have explored how a transition to renewable hydrogen might begin. The goal of our current work is to identify promising strategies leading from near term hydrogen markets and technologies toward eventual large scale use of renewable hydrogen as an energy carrier. Our approach has been to assess the entire hydrogen energy system from production through end-use considering technical performance, economics, infrastructure and environmental issues. This work is part of the systems analysis activity of the DOE Hydrogen Program. In this paper we first summarize the results of three tasks which were completed during the past year under NREL Contract No. XR-11265-2: in Task 1, we carried out assessments of near term options for supplying hydrogen transportation fuel from natural gas; in Task 2, we assessed the feasibility of using the existing natural gas system with hydrogen and hydrogen blends; and in Task 3, we carried out a study of PEM fuel cells for residential cogeneration applications, a market which might have less stringent cost requirements than transportation. We then give preliminary results for two other tasks which are ongoing under DOE Contract No. DE-FG04-94AL85803: In Task 1 we are assessing the technical options for low cost small scale production of hydrogen from natural gas, considering (a) steam reforming, (b) partial oxidation and (c) autothermal reforming, and in Task 2 we are assessing potential markets for hydrogen in Southern California.

  11. Modeling systemic and renal gadolinium chelate transport with MRI

    Energy Technology Data Exchange (ETDEWEB)

    Votaw, John R.; Martin, Diego [Emory University Hospital, Department of Radiology, Atlanta, GA (United States)

    2008-01-15

    The advent of modern MRI scanners and computer equipment permits the rapid sequential collection of images of gadolinium chelate (Gd) transit through the kidney. The excellent spatial and temporal (0.9 s) resolution permits analyzing the shape of the recovered curves with a sophisticated model that includes both space and time. The purpose of this manuscript is to present such a mathematical model. By building into the model significant physical processes that contribute to the shape of the measured curve, quantitative values can be assigned to important parameters. In this work, quantitative values are determined for blood dispersion through the cardio-pulmonary system, systemic clearance rate of Gd, blood flow into each kidney, blood transit time in each kidney, the extraction rate of Gd across the capillary membrane, interstitial distribution volume, and the GFR for each kidney. (orig.)

  12. Quantitative evaluation of the reticuloendothelial system function with dynamic MRI.

    Directory of Open Access Journals (Sweden)

    Ting Liu

    Full Text Available To evaluate the reticuloendothelial system (RES function by real-time imaging blood clearance as well as hepatic uptake of superparamagnetic iron oxide nanoparticle (SPIO using dynamic magnetic resonance imaging (MRI with two-compartment pharmacokinetic modeling.Kinetics of blood clearance and hepatic accumulation were recorded in young adult male 01b74 athymic nude mice by dynamic T2* weighted MRI after the injection of different doses of SPIO nanoparticles (0.5, 3 or 10 mg Fe/kg. Association parameter, Kin, dissociation parameter, Kout, and elimination constant, Ke, derived from dynamic data with two-compartment model, were used to describe active binding to Kupffer cells and extrahepatic clearance. The clodrosome and liposome were utilized to deplete macrophages and block the RES function to evaluate the capability of the kinetic parameters for investigation of macrophage function and density.The two-compartment model provided a good description for all data and showed a low sum squared residual for all mice (0.27±0.03. A lower Kin, a lower Kout and a lower Ke were found after clodrosome treatment, whereas a lower Kin, a higher Kout and a lower Ke were observed after liposome treatment in comparison to saline treatment (P<0.005.Dynamic SPIO-enhanced MR imaging with two-compartment modeling can provide information on RES function on both a cell number and receptor function level.

  13. Multiple Energy System Analysis of Smart Energy Systems

    DEFF Research Database (Denmark)

    Thellufsen, Jakob Zinck

    2015-01-01

    thermal grids and smart gas grids, Smart Energy Systems moves the flexibility away from the fuel as is the case in current energy systems and into the system itself. However, most studies applying a Smart Energy System approach deals with analyses for either single countries or whole continents......To eliminate the use of fossil fuels in the energy sector it is necessary to transition to future 100% renewable energy systems. One approach for this radical change in our energy systems is Smart Energy Systems. With a focus on development and interaction between smart electricity grids, smart......, but it is unclear how regions, municipalities, and communities should deal with these national targets. It is necessary to be able to provide this information since Smart Energy Systems utilize energy resources and initiatives that have strong relations to local authorities and communities, such as onshore wind...

  14. Energy systems in transition

    International Nuclear Information System (INIS)

    Haefele, W.

    1989-01-01

    The principal point of the author was to discuss energy systems (ES) in transition, transition addresses the next 10-25 years, and strategy of the transition. He considers different scenarios of future development of ES. Further he presents considerations elaborated during the last years on the concept of novel horizontally integrated ES which gives promise to be at least an approximation to the desired object of no emissions. The main ideas of the concept are: to decompose and thereby clean all the primary inputs before they are brought to combustion; to develop a network combining all the primary inputs to an integrated supply structure of high absorption, buffer, and storage capacity that resembles in some way the supply and utility functions of the well established electric grid but completes it at best on the basis of mass flows; to achieve a high flexibility in supplying the final energy. The author considers the long run perspective of hydrogen, solar, and nuclear energy with respect to alternative energy sources. 6 refs, 24 figs

  15. Energy System Analysis of 100 Per cent Renewable Energy Systems

    DEFF Research Database (Denmark)

    Lund, Henrik; Mathiesen, Brian Vad

    2007-01-01

    This paper presents the methodology and results of the overall energy system analysis of a 100 per cent renewable energy system. The input for the systems is the result of a project of the Danish Association of Engineers, in which 1600 participants during more than 40 seminars discussed...... and designed a model for the future energy system of Denmark, putting emphasis on energy efficiency, CO2 reduction, and industrial development. The energy system analysis methodology includes hour by hour computer simulations leading to the design of flexible energy systems with the ability to balance...... the electricity supply and demand and to exchange electricity productions on the international electricity markets. The results are detailed system designs and energy balances for two energy target years: year 2050 with 100 per cent renewable energy from biomass and combinations of wind, wave and solar power...

  16. Energy Storage Systems

    Science.gov (United States)

    Elliott, David

    2017-07-01

    As renewable energy use expands there will be a need to develop ways to balance its variability. Storage is one of the options. Presently the main emphasis is for systems storing electrical power in advanced batteries (many of them derivatives of parallel developments in the electric vehicle field), as well as via liquid air storage, compressed air storage, super-capacitors and flywheels, and, the leader so far, pumped hydro reservoirs. In addition, new systems are emerging for hydrogen generation and storage, feeding fuel cell power production. Heat (and cold) is also a storage medium and some systems exploit thermal effects as part of wider energy management activity. Some of the more exotic ones even try to use gravity on a large scale. This short book looks at all the options, their potentials and their limits. There are no clear winners, with some being suited to short-term balancing and others to longer-term storage. The eventual mix adopted will be shaped by the pattern of development of other balancing measures, including smart-grid demand management and super-grid imports and exports.

  17. A novel optically transparent RF shielding for fully integrated PET/MRI systems

    Science.gov (United States)

    Parl, C.; Kolb, A.; Schmid, A. M.; Wehrl, H. F.; Disselhorst, J. A.; Soubiran, P. D.; Stricker-Shaver, D.; Pichler, B. J.

    2017-09-01

    Preclinical imaging benefits from simultaneous acquisition of high-resolution anatomical and molecular data. Additionally, PET/MRI systems can provide functional PET and functional MRI data. To optimize PET sensitivity, we propose a system design that fully integrates the MRI coil into the PET system. This allows positioning the scintillators near the object but requires an optimized design of the MRI coil and PET detector. It further requires a new approach in realizing the radiofrequency (RF) shielding. Thus, we propose the use of an optically transparent RF shielding material between the PET scintillator and the light sensor, suppressing the interference between both systems. We evaluated two conductive foils (ITO, 9900) and a wire mesh. The PET performance was tested on a dual-layer scintillator consisting of 12  ×  12 LSO matrices, shifted by half a pitch. The pixel size was 0.9  ×  0.9 mm2 the lengths were 10.0 mm and 5.0 mm, respectively. For a light sensor, we used a 4  ×  4 SiPM array. The RF attenuation was measured from 320 kHz to 420 MHz using two pick-up coils. MRI-compatibility and shielding effect of the materials were evaluated with an MRI system. The average FWHM energy resolution at 511 keV of all 144 crystals of the layer next to the SiPM was deteriorated from 15.73  ±  0.24% to 16.32  ±  0.13%, 16.60  ±  0.25%, and 19.16  ±  0.21% by the ITO foil, 9900 foil, mesh material, respectively. The average peak-to-valley ratio of the PET detector changed from 5.77  ±  0.29 to 4.50  ±  0.39, 4.78  ±  0.48, 3.62  ±  0.16, respectively. The ITO, 9900, mesh attenuated the scintillation light by 11.3  ±  1.6%, 11.0  ±  1.8%, 54.3  ±  0.4%, respectively. To attenuate the RF from 20 MHz to 200 MHz, mesh performed better than copper. The results show that an RF shielding material that is sufficiently transparent for

  18. Techniques for Interventional MRI Guidance in Closed-Bore Systems.

    Science.gov (United States)

    Busse, Harald; Kahn, Thomas; Moche, Michael

    2018-02-01

    Efficient image guidance is the basis for minimally invasive interventions. In comparison with X-ray, computed tomography (CT), or ultrasound imaging, magnetic resonance imaging (MRI) provides the best soft tissue contrast without ionizing radiation and is therefore predestined for procedural control. But MRI is also characterized by spatial constraints, electromagnetic interactions, long imaging times, and resulting workflow issues. Although many technical requirements have been met over the years-most notably magnetic resonance (MR) compatibility of tools, interventional pulse sequences, and powerful processing hardware and software-there is still a large variety of stand-alone devices and systems for specific procedures only.Stereotactic guidance with the table outside the magnet is common and relies on proper registration of the guiding grids or manipulators to the MR images. Instrument tracking, often by optical sensing, can be added to provide the physicians with proper eye-hand coordination during their navigated approach. Only in very short wide-bore systems, needles can be advanced at the extended arm under near real-time imaging. In standard magnets, control and workflow may be improved by remote operation using robotic or manual driving elements.This work highlights a number of devices and techniques for different interventional settings with a focus on percutaneous, interstitial procedures in different organ regions. The goal is to identify technical and procedural elements that might be relevant for interventional guidance in a broader context, independent of the clinical application given here. Key challenges remain the seamless integration into the interventional workflow, safe clinical translation, and proper cost effectiveness.

  19. Smart energy and smart energy systems

    DEFF Research Database (Denmark)

    Lund, Henrik; Østergaard, Poul Alberg; Connolly, David

    2017-01-01

    In recent years, the terms “Smart Energy” and “Smart Energy Systems” have been used to express an approach that reaches broader than the term “Smart grid”. Where Smart Grids focus primarily on the electricity sector, Smart Energy Systems take an integrated holistic focus on the inclusion of more...... sectors (electricity, heating, cooling, industry, buildings and transportation) and allows for the identification of more achievable and affordable solutions to the transformation into future renewable and sustainable energy solutions. This paper first makes a review of the scientific literature within...... the field. Thereafter it discusses the term Smart Energy Systems with regard to the issues of definition, identification of solu- tions, modelling, and integration of storage. The conclusion is that the Smart Energy System concept represents a scientific shift in paradigms away from single-sector thinking...

  20. Energy Systems Integration News | Energy Systems Integration Facility |

    Science.gov (United States)

    the Energy Systems Integration Facility as part of NREL's work with SolarCity and the Hawaiian Electric Companies. Photo by Amy Glickson, NREL Welcome to Energy Systems Integration News, NREL's monthly date on the latest energy systems integration (ESI) developments at NREL and worldwide. Have an item

  1. Energy Systems High-Pressure Test Laboratory | Energy Systems Integration

    Science.gov (United States)

    Facility | NREL Energy Systems High-Pressure Test Laboratory Energy Systems High-Pressure Test Laboratory In the Energy Systems Integration Facility's High-Pressure Test Laboratory, researchers can safely test high-pressure hydrogen components. Photo of researchers running an experiment with a hydrogen fuel

  2. The OMERACT Rheumatoid Arthritis Magnetic Resonance Imaging (MRI) Scoring System: Updated Recommendations by the OMERACT MRI in Arthritis Working Group.

    Science.gov (United States)

    Østergaard, Mikkel; Peterfy, Charles G; Bird, Paul; Gandjbakhch, Frédérique; Glinatsi, Daniel; Eshed, Iris; Haavardsholm, Espen A; Lillegraven, Siri; Bøyesen, Pernille; Ejbjerg, Bo; Foltz, Violaine; Emery, Paul; Genant, Harry K; Conaghan, Philip G

    2017-11-01

    The Outcome Measures in Rheumatology (OMERACT) Rheumatoid Arthritis (RA) Magnetic Resonance Imaging (MRI) scoring system (RAMRIS), evaluating bone erosion, bone marrow edema/osteitis, and synovitis, was introduced in 2002, and is now the standard method of objectively quantifying inflammation and damage by MRI in RA trials. The objective of this paper was to identify subsequent advances and based on them, to provide updated recommendations for the RAMRIS. MRI studies relevant for RAMRIS and technical and scientific advances were analyzed by the OMERACT MRI in Arthritis Working Group, which used these data to provide updated considerations on image acquisition, RAMRIS definitions, and scoring systems for the original and new RA pathologies. Further, a research agenda was outlined. Since 2002, longitudinal studies and clinical trials have documented RAMRIS variables to have face, construct, and criterion validity; high reliability and sensitivity to change; and the ability to discriminate between therapies. This has enabled RAMRIS to demonstrate inhibition of structural damage progression with fewer patients and shorter followup times than has been possible with conventional radiography. Technical improvements, including higher field strengths and improved pulse sequences, allow higher image resolution and contrast-to-noise ratio. These have facilitated development and validation of scoring methods of new pathologies: joint space narrowing and tenosynovitis. These have high reproducibility and moderate sensitivity to change, and can be added to RAMRIS. Combined scores of inflammation or joint damage may increase sensitivity to change and discriminative power. However, this requires further research. Updated 2016 RAMRIS recommendations and a research agenda were developed.

  3. Positioning device for MRI-guided high intensity focused ultrasound system

    Energy Technology Data Exchange (ETDEWEB)

    Damianou, Christakis [Frederick Institute of Technology (FIT), Limassol (Cyprus); MEDSONIC, LTD, Limassol (Cyprus); Ioannides, Kleanthis [Polikliniki Igia, Limassol (Cyprus); Milonas, Nicos [Frederick Institute of Technology (FIT), Limassol (Cyprus)

    2008-04-15

    A prototype magnetic resonance imaging (MRI)- compatible positioning device was used to move an MRI-guided high intensity focused ultrasound (HIFU) transducer. The positioning device has three user-controlled degrees of freedom that allow access to various targeted lesions. The positioning device was designed and fabricated using construction materials selected for compatibility with high magnetic fields and fast switching magnetic field gradients encountered inside MRI scanners. The positioning device incorporates only MRI compatible materials such as piezoelectric motors, plastic sheets, brass screws, plastic pulleys and timing belts. The HIFU/MRI system includes the multiple subsystems (a) HIFU system, (b) MR imaging, (c) Positioning device (robot) and associate drivers, (d) temperature measurement, (e) cavitation detection, (f) MRI compatible camera, and (g) Soft ware. The MRI compatibility of the system was successfully demonstrated in a clinical high-field MRI scanner. The ability of the robot to accurately move the transducer thus creating discrete and overlapping lesions in biological tissue was tested successfully. A simple, cost effective, portable positioning device has been developed which can be used in virtually any clinical MRI scanner since it can be sited on the scanner's table. The propagation of HIFU can use either a lateral or superior-inferior approach. Discrete and large lesions were created successfully with reproducible results. (orig.)

  4. HYDROKINETIC ENERGY CONVERSION SYSTEMS: PROSPECTS ...

    African Journals Online (AJOL)

    eobe

    Hydrokinetic energy conversion systems utilize the kinetic energy of flowing water bodies with little or no head to generate ... generator. ... Its principle of operation is analogous to that of wind ..... Crisis-solar and wind power systems, 2009,.

  5. Integrated energy systems and local energy markets

    DEFF Research Database (Denmark)

    Lund, Henrik; Münster, Ebbe

    2006-01-01

    Significant benefits are connected with an increase in the flexibility of the Danish energy system. On the one hand, it is possible to benefit from trading electricity with neighbouring countries, and on the other, Denmark will be able to make better use of wind power and other types of renewable...... energy in the future. This paper presents the analysis of different ways of increasing flexibility in the Danish energy system by the use of local regulation mechanisms. This strategy is compared with the opposite extreme, i.e. trying to solve all balancing problems via electricity trade...

  6. Brain MRI Tumor Detection using Active Contour Model and Local Image Fitting Energy

    Science.gov (United States)

    Nabizadeh, Nooshin; John, Nigel

    2014-03-01

    Automatic abnormality detection in Magnetic Resonance Imaging (MRI) is an important issue in many diagnostic and therapeutic applications. Here an automatic brain tumor detection method is introduced that uses T1-weighted images and K. Zhang et. al.'s active contour model driven by local image fitting (LIF) energy. Local image fitting energy obtains the local image information, which enables the algorithm to segment images with intensity inhomogeneities. Advantage of this method is that the LIF energy functional has less computational complexity than the local binary fitting (LBF) energy functional; moreover, it maintains the sub-pixel accuracy and boundary regularization properties. In Zhang's algorithm, a new level set method based on Gaussian filtering is used to implement the variational formulation, which is not only vigorous to prevent the energy functional from being trapped into local minimum, but also effective in keeping the level set function regular. Experiments show that the proposed method achieves high accuracy brain tumor segmentation results.

  7. Multi-Channel RF System for MRI-Guided Transurethral Ultrasound Thermal Therapy

    Science.gov (United States)

    Yak, Nicolas; Asselin, Matthew; Chopra, Rajiv; Bronskill, Michael

    2009-04-01

    MRI-guided transurethral ultrasound thermal therapy is an approach to treating localized prostate cancer which targets precise deposition of thermal energy within a confined region of the gland. This treatment requires a system incorporating a heating applicator with multiple planar ultrasound transducers and associated RF electronics to control individual elements independently in order to achieve accurate 3D treatment. We report the design, construction, and characterization of a prototype multi-channel system capable of controlling 16 independent RF signals for a 16-element heating applicator. The main components are a control computer, microcontroller, and a 16-channel signal generator with 16 amplifiers, each incorporating a low-pass filter and transmitted/reflected power detection circuit. Each channel can deliver from 0.5 to 10 W of electrical power and good linearity from 3 to 12 MHz. Harmonic RF signals near the Larmor frequency of a 1.5 T MRI were measured to be below -30 dBm and heating experiments within the 1.5 T MR system showed no significant decrease in SNR of the temperature images. The frequency and power for all 16 channels could be changed in less than 250 ms, which was sufficiently rapid for proper performance of the control algorithms. A common backplane design was chosen which enabled an inexpensive, modular approach for each channel resulting in an overall system with minimal footprint.

  8. First image from a combined positron emission tomography and field-cycled MRI system.

    Science.gov (United States)

    Bindseil, Geron A; Gilbert, Kyle M; Scholl, Timothy J; Handler, William B; Chronik, Blaine A

    2011-07-01

    Combining positron emission tomography and MRI modalities typically requires using either conventional MRI with a MR-compatible positron emission tomography system or a modified MR system with conventional positron emission tomography. A feature of field-cycled MRI is that all magnetic fields can be turned off rapidly, enabling the use of conventional positron emission tomography detectors based on photomultiplier tubes. In this demonstration, two photomultiplier tube-based positron emission tomography detectors were integrated with a field-cycled MRI system (0.3 T/4 MHz) by placing them into a 9-cm axial gap. A positron emission tomography-MRI phantom consisting of a triangular arrangement of positron-emitting point sources embedded in an onion was imaged in a repeating interleaved sequence of ∼1 sec MRI then 1 sec positron emission tomography. The first multimodality images from the combined positron emission tomography and field-cycled MRI system show no additional artifacts due to interaction between the systems and demonstrate the potential of this approach to combining positron emission tomography and MRI. Copyright © 2010 Wiley-Liss, Inc.

  9. Wind Energy Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Ma, Ke

    2017-01-01

    transmission networks at the scale of hundreds of megawatts. As its level of grid penetration has begun to increase dramatically, wind power is starting to have a significant impact on the operation of the modern grid system. Advanced power electronics technologies are being introduced to improve......Wind power now represents a major and growing source of renewable energy. Large wind turbines (with capacities of up to 6-8 MW) are widely installed in power distribution networks. Increasing numbers of onshore and offshore wind farms, acting as power plants, are connected directly to power...... the characteristics of the wind turbines, and make them more suitable for integration into the power grid. Meanwhile, there are some emerging challenges that still need to be addressed. This paper provides an overview and discusses some trends in the power electronics technologies used for wind power generation...

  10. Energy Systems Integration News | Energy Systems Integration Facility |

    Science.gov (United States)

    organization and independent system operator settle energy transactions in its real-time markets at the same time interval it dispatches energy, and settle operating reserves transactions in its real-time markets the electric grid. These control systems will enable real-time coordination between distributed energy

  11. Acoustic fMRI noise : Linear time-invariant system model

    NARCIS (Netherlands)

    Sierra, Carlos V. Rizzo; Versluis, Maarten J.; Hoogduin, Johannes M.; Duifhuis, Hendrikus (Diek)

    Functional magnetic resonance imaging (fMRI) enables sites of brain activation to be localized in human subjects. For auditory system studies, however, the acoustic noise generated by the scanner tends to interfere with the assessments of this activation. Understanding and modeling fMRI acoustic

  12. Vantage TitanTM 3T 3-tesla MRI system with enhanced serviceability and comfort

    International Nuclear Information System (INIS)

    Kanazawa, Hitoshi; Okamoto, Kazuya; Yamamoto, Takao

    2011-01-01

    Since 3-tesla magnetic resonance imaging (MRI) systems appeared on the market, in addition to their clinical usefulness a variety of issues have been pointed out in the clinical setting. The 3-tesla MRI system has therefore gained a reputation as a difficult system suitable only for hospital facilities including university hospitals that specialize in medical research. To rectify this situation, Toshiba Medical Systems Corporation has developed the Vantage Titan TM 3T, which is expected to not only improve the MRI examination environment, but also to be applicable to patients with claustrophobia and those with large physiques for whom MRI examination has not been appropriate until now, while maintaining the clinical usefulness of the 3-tesla MRI system. The Vantage Titan 3T system also incorporates the Pianissimo TM noise reduction mechanism, which has already been introduced in our 1.5-tesla MRI system and has been highly evaluated by the market. This reduces the stress of patients by providing a quieter and more open examination environment compared with conventional MRI systems. (author)

  13. Renewable energy covernance systems

    International Nuclear Information System (INIS)

    Hvelplund, F.

    2001-01-01

    The 'political quota-/certificate price market' system introduces an inefficient competition between energy robots, and weakens the increasingly important competition between equipment producers. It hampers the competition between investors by making it difficult for neighbours and local investors to invest in wind turbines. Due to its mono price character, it gives too high profits to wind turbine owners at very good wind sites, and not high enough to wind turbine owners at poor wind sites. The 'political quota-/certificate price market' system is very far from being a market model, as the RE amount is politically decided and the certificate market price is also political influenced. The conclusion, therefore, is that it is time to find a RE governance model that considers the specific needs and characteristics of RE technologies. The present analysis strongly indicates that a 'political price-/amount market' model in this connection is far better than the 'political quota-/certificate price market' model. Furthermore, a common EU model, based on the principle of site efficiency, would be much more flexible, cheaper and easier to pursue than the 'political quota-/certificate price market', or mono price model, which is designed for uranium and fossil fuel technologies, and represents a governance model designed for the technologies of yesterday. (EHS)

  14. Energy Systems Integration News | Energy Systems Integration Facility |

    Science.gov (United States)

    grids. In terms of paper sessions, NREL ESI researcher Santosh Veda chaired a session on energy Kroposki chaired a session on advanced renewable energy power systems. While Veda, Muljadi, and Kroposki

  15. Diffusion microscopist simulator - The development and application of a Monte Carlo simulation system for diffusion MRI

    International Nuclear Information System (INIS)

    Yeh, C.H.

    2011-09-01

    Diffusion magnetic resonance imaging (dMRI) has made a significant breakthrough in neurological disorders and brain research thanks to its exquisite sensitivity to tissue cyto-architecture. However, as the water diffusion process in neuronal tissues is a complex biophysical phenomena at molecular scale, it is difficult to infer tissue microscopic characteristics on a voxel scale from dMRI data. The major methodological contribution of this thesis is the development of an integrated and generic Monte Carlo simulation framework, 'Diffusion Microscopist Simulator' (DMS), which has the capacity to create 3D biological tissue models of various shapes and properties, as well as to synthesize dMRI data for a large variety of MRI methods, pulse sequence design and parameters. DMS aims at bridging the gap between the elementary diffusion processes occurring at a micrometric scale and the resulting diffusion signal measured at millimetric scale, providing better insights into the features observed in dMRI, as well as offering ground-truth information for optimization and validation of dMRI acquisition protocols for different applications. We have verified the performance and validity of DMS through various benchmark experiments, and applied to address particular research topics in dMRI. Based on DMS, there are two major application contributions in this thesis. First, we use DMS to investigate the impact of finite diffusion gradient pulse duration (delta) on fibre orientation estimation in dMRI. We propose that current practice of using long delta, which is enforced by the hardware limitation of clinical MRI scanners, is actually beneficial for mapping fibre orientations, even though it violates the underlying assumption made in q-space theory. Second, we employ DMS to investigate the feasibility of estimating axon radius using a clinical MRI system. The results suggest that the algorithm for mapping the direct microstructures is applicable to dMRI data acquired from

  16. Longitudinal diffusion MRI for treatment response assessment: Preliminary experience using an MRI-guided tri-cobalt 60 radiotherapy system.

    Science.gov (United States)

    Yang, Yingli; Cao, Minsong; Sheng, Ke; Gao, Yu; Chen, Allen; Kamrava, Mitch; Lee, Percy; Agazaryan, Nzhde; Lamb, James; Thomas, David; Low, Daniel; Hu, Peng

    2016-03-01

    To demonstrate the preliminary feasibility of a longitudinal diffusion magnetic resonance imaging (MRI) strategy for assessing patient response to radiotherapy at 0.35 T using an MRI-guided radiotherapy system (ViewRay). Six patients (three head and neck cancer, three sarcoma) who underwent fractionated radiotherapy were enrolled in this study. A 2D multislice spin echo single-shot echo planar imaging diffusion pulse sequence was implemented on the ViewRay system and tested in phantom studies. The same pulse sequence was used to acquire longitudinal diffusion data (every 2-5 fractions) on the six patients throughout the entire course of radiotherapy. The reproducibility of the apparent diffusion coefficient (ADC) measurements was assessed using reference regions and the temporal variations of the tumor ADC values were evaluated. In diffusion phantom studies, the ADC values measured on the ViewRay system matched well with reference ADC values with ViewRay MRI. Larger patient cohort studies are warranted to correlate the longitudinal diffusion measurements to patient outcomes. Such an approach may enable response-guided adaptive radiotherapy.

  17. National Energy Outlook Modelling System

    Energy Technology Data Exchange (ETDEWEB)

    Volkers, C.M. [ECN Policy Studies, Petten (Netherlands)

    2013-12-15

    For over 20 years, the Energy research Centre of the Netherlands (ECN) has been developing the National Energy Outlook Modelling System (NEOMS) for Energy projections and policy evaluations. NEOMS enables 12 energy models of ECN to exchange data and produce consistent and detailed results.

  18. Third Degree Skin Burns Caused by an MRI Compatible Electrocardiographic Monitoring System

    DEFF Research Database (Denmark)

    Brix, Lau; Isaksen, Christin Rosendahl Graff; Kristensen, Birgitte Hornbæk

    of the assigned compatibility specifications of the leads due to the use of TFE sequences with high SAR values. MRI compatible monitoring systems are only safe when used with proper care. The presented burn cases may have been avoided if space had been provided between the ECG leads and the skin using a cloth....... This holds true even in cases in which the devices are MRI compatible and therefore safe in specified MRI environments. Of particular interest to this case report is skin burns caused by the ECG monitoring equipment. In this context, several cases of ECG electrode related burns have been reported, while...... burns caused by the ECG cables are less common [1]. This case report presents two unusual cases of skin burns which were caused by MRI safe ECG leads during scanning. Cases:Two patients suffered third degree burns using MRI approved ECG leads (Medrad® Veris MR Monitor system) in a Siemens Skyra 3...

  19. Smart Energy Systems and Energy Transition

    International Nuclear Information System (INIS)

    Duic, N.

    2016-01-01

    Transition to decarbonized energy systems is becoming more attractive with fall of investment costs of renewables and volatile prices and political insecurity of fossil fuels. Improving energy efficiency, especially of buildings and transport, is important, but due to long life of buildings, it will be a slow way of decarbonization. The renewable energy resources are bountiful, especially wind and solar, while integrating them into current energy systems is proving to be a challenge. Solar has reached grid parity making it cheapest electricity source for retail customers in most of the World, creating new prosumer markets. It has started to reach cost parity in sunny countries, and soon solar energy will be cheapest everywhere. The limit of cheap and easy integration for wind is around 20% of yearly electricity generation, while a combined wind and solar may reach 30%. Going any further asks for implementation of completely free energy markets (involving day ahead, intraday and various reserve and ancillary services markets), demand response, coupling of wholesale and retail energy prices, and it involves integration between electricity, heat, water and transport systems. The cheapest and simplest way of increasing further the penetration of renewables is integrating power and heating/cooling systems through the use of district heating and cooling (which may be centrally controlled and may have significant heat storage capacity), since power to heat technologies are excellent for demand response. District cooling is of particular importance to historic cities that want to remove split systems from their facades. In countries with low heat demand water supply system may be used to increase the penetration of renewables, by using water at higher potential energy as storage media, or in dry climates desalination and stored water may be used for those purposes, and reversible hydro may be used as balancing technology. Electrification of personal car transport allows

  20. MRI study of degenerative process in multiple system atrophy

    International Nuclear Information System (INIS)

    Yagishita, Toshiyuki; Kojima, Shigeyuki; Hirayama, Keizo

    1995-01-01

    The characteristic morphological changes of the brainstem and cerebellar regions of multiple system atrophy (MSA) were studied by MRI in varing subtypes, that is olivoponto cerebellar atrophy (OPCA: 23 cases), striatonigral degeneration (SND: 7 cases) and Shy-Drager's syndrome (SDS: 9 cases). OPCA was characterized by atrophy of the entire regions of the brainstem and the cerebellum. SND and SDS tended to show atrophy similar in type but lessin extent to OPCA. The common lesions in MSA were atrophy of the pontine base and cerebellum, and dilation of the fourth ventricle. Atrophy of the pontine base was more dominant in the inferior part than in the superior part, and cerebellar atrophy was more dominant in the superior part than in the inferior part, indicating that degeneration of the pontocerebellar pathway proceeds principally along fibers connecting the inferior part of the pons and the superior part of the cerebellum. Dilation of the fourth ventricle indicated atrophy of the middle cerebellar peduncle. In almost all the cases of OPCA and about a half the cases of SND and SDS, the pontine base and the middle cerebellar peduncle appeared as high signal intensity on T 2 weighted image and as low intensity on T 1 , suggesting degeneration and demyelination. In a few cases of OPCA, the dorsolateral part of the putamen were demonstrated as low signal intensity on T 2 weighted image. (author)

  1. MRI study of degenerative process in multiple system atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Yagishita, Toshiyuki; Kojima, Shigeyuki; Hirayama, Keizo [Chiba Univ. (Japan). School of Medicine

    1995-02-01

    The characteristic morphological changes of the brainstem and cerebellar regions of multiple system atrophy (MSA) were studied by MRI in varing subtypes, that is olivoponto cerebellar atrophy (OPCA: 23 cases), striatonigral degeneration (SND: 7 cases) and Shy-Drager`s syndrome (SDS: 9 cases). OPCA was characterized by atrophy of the entire regions of the brainstem and the cerebellum. SND and SDS tended to show atrophy similar in type but lessin extent to OPCA. The common lesions in MSA were atrophy of the pontine base and cerebellum, and dilation of the fourth ventricle. Atrophy of the pontine base was more dominant in the inferior part than in the superior part, and cerebellar atrophy was more dominant in the superior part than in the inferior part, indicating that degeneration of the pontocerebellar pathway proceeds principally along fibers connecting the inferior part of the pons and the superior part of the cerebellum. Dilation of the fourth ventricle indicated atrophy of the middle cerebellar peduncle. In almost all the cases of OPCA and about a half the cases of SND and SDS, the pontine base and the middle cerebellar peduncle appeared as high signal intensity on T{sub 2} weighted image and as low intensity on T{sub 1}, suggesting degeneration and demyelination. In a few cases of OPCA, the dorsolateral part of the putamen were demonstrated as low signal intensity on T{sub 2} weighted image. (author).

  2. Polish energy-system modernisation

    International Nuclear Information System (INIS)

    Drozdz, M.

    2003-01-01

    The Polish energy-system needs intensive investments in new technologies, which are energy efficient, clean and cost effective. Since the early 1990s, the Polish economy has had practically full access to modern technological devices, equipment and technologies. Introducing new technologies is a difficult task for project teams, constructors and investors. The author presents a set of principles for project teams useful in planning and energy modernisation. Several essential features are discussed: Energy-efficient appliances and systems; Choice of energy carriers, media and fuels; Optimal tariffs, maximum power and installed power; Intelligent, integrated, steering systems; Waste-energy recovery; Renewable-energy recovery. In practice there are several difficulties connected with planning and realising good technological and economic solutions. The author presents his own experiences of energy-system modernisation of industrial processes and building new objects. (Author)

  3. MRI changes in the central nervous system in a child with lupus erythematosus

    International Nuclear Information System (INIS)

    Gieron, M.A.; Khoromi, S.; Campos, A.

    1995-01-01

    We report on a 10-year-old girl with systemic lupus erythematosus who presented in status epilepticus as the only manifestation of central nervous system involvement. MRI of the brain showed diffuse gray and white matter lesions which almost completely resolved after treatment with methylprednisolone. MRI findings in this child are similar to those in adults with diffuse clinical manifestations. The study is essential in the initial evaluation of patients suspected of central nervous system lupus. (orig.)

  4. MRI changes in the central nervous system in a child with lupus erythematosus

    Energy Technology Data Exchange (ETDEWEB)

    Gieron, M A [Dept. of Pediatrics, Univ. of South Florida, Coll. of Medicine, Tampa, FL (United States); Khoromi, S [Dept. of Neurology, Univ. of South Florida, Coll. of Medicine, Tampa, FL (United States); Campos, A [Dept. of Pediatrics, Univ. of South Florida, Coll. of Medicine, Tampa, FL (United States)

    1995-05-01

    We report on a 10-year-old girl with systemic lupus erythematosus who presented in status epilepticus as the only manifestation of central nervous system involvement. MRI of the brain showed diffuse gray and white matter lesions which almost completely resolved after treatment with methylprednisolone. MRI findings in this child are similar to those in adults with diffuse clinical manifestations. The study is essential in the initial evaluation of patients suspected of central nervous system lupus. (orig.)

  5. Constitutional compatibility of energy systems

    International Nuclear Information System (INIS)

    Rossnagel, A.

    1983-01-01

    The paper starts from the results of the Enquiry Commission on 'Future Nuclear Energy Policy' of the 8th Federal German Parliament outlining technically feasible energy futures in four 'pathways'. For the purpose of the project, which was to establish the comparative advantages and disadvantages of different energy systems, these four scenarios were reduced to two alternatives: cases K (= nuclear energy) and S (= solar energy). The question to Ge put is: Which changes within our legal system will be ushered in by certain technological developments and how do these changes relate to the legal condition intended so far. Proceeding in this manner will not lead to the result of a nuclear energy system or a solar energy system being in conformity or in contradiction with the constitutional law, but will provide a catalogue of implications orientated to the aims of legal standards: a person deciding in favour of a nuclear energy system or a solar energy system supports this or that development of constitutional policy, and a person purishing this or that aim of legal policy should be consistent and decide in favour of this or that energy system. The investigation of constitutional compatibility leads to the question what effects different energy systems will have on the forms of political intercourse laid down in the constitutional law, which are orientated to models of a liberal constitutional tradition of citizens. (orig./HSCH) [de

  6. Diagnostic performance of dual-energy CT stress myocardial perfusion imaging: direct comparison with cardiovascular MRI.

    Science.gov (United States)

    Ko, Sung Min; Song, Meong Gun; Chee, Hyun Kun; Hwang, Hweung Kon; Feuchtner, Gudrun Maria; Min, James K

    2014-12-01

    The purpose of this study was to assess the diagnostic performance of stress perfusion dual-energy CT (DECT) and its incremental value when used with coronary CT angiography (CTA) for identifying hemodynamically significant coronary artery disease. One hundred patients with suspected or known coronary artery disease without chronic myocardial infarction detected with coronary CTA underwent stress perfusion DECT, stress cardiovascular perfusion MRI, and invasive coronary angiography (ICA). Stress perfusion DECT and cardiovascular stress perfusion MR images were used for detecting perfusion defects. Coronary CTA and ICA were evaluated in the detection of ≥50% coronary stenosis. The diagnostic performance of coronary CTA for detecting hemo-dynamically significant stenosis was assessed before and after stress perfusion DECT on a per-vessel basis with ICA and cardiovascular stress perfusion MRI as the reference standard. The performance of stress perfusion DECT compared with cardiovascular stress perfusion MRI on a per-vessel basis in the detection of perfusion defects was sensitivity, 89%; specificity, 74%; positive predictive value, 73%; negative predictive value, 90%. Per segment, these values were sensitivity, 76%; specificity, 80%; positive predictive value, 63%; and negative predictive value, 88%. Compared with ICA and cardiovascular stress perfusion MRI per vessel territory the sensitivity, specificity, positive predictive value, and negative predictive value of coronary CTA were 95%, 61%, 61%, and 95%. The values for stress perfusion DECT were 92%, 72%, 68%, and 94%. The values for coronary CTA and stress perfusion DECT were 88%, 79%, 73%, and 91%. The ROC AUC increased from 0.78 to 0.84 (p=0.02) with the use of coronary CTA and stress perfusion DECT compared with coronary CTA alone. Stress perfusion DECT plays a complementary role in enhancing the accuracy of coronary CTA for identifying hemodynamically significant coronary stenosis.

  7. Smart Energy Systems

    DEFF Research Database (Denmark)

    Connolly, David; Lund, Henrik; Mathiesen, Brian Vad

    2013-01-01

    • To reduce the costs of energy towards 2050 This transition faces many challenges from a variety of different perspectives, including: • Technology: The development of new technologies and infrastructures, which will enable us to utilise renewable energy resources. • Business: The design of new markets...

  8. Energy Systems Integration News | Energy Systems Integration Facility |

    Science.gov (United States)

    , utilities can operate more efficiently and profitably. That can increase the use of renewable energy sources challenge to utility companies, grid operators, and other stakeholders involved in wind energy integration recording is available from the July 16 webinar "Smart Grid Research at NREL's Energy Systems

  9. Fusion in the energy system

    DEFF Research Database (Denmark)

    Fusion energy is the fundamental energy source of the Universe, as the energy of the Sun and the stars are produced by fusion of e.g. hydrogen to helium. Fusion energy research is a strongly international endeavor aiming at realizing fusion energy production in power plants on Earth. Reaching...... of integration into the future electricity system and socio-economic studies of fusion energy will be presented, referring to the programme of Socio-Economic Research on Fusion (SERF) under the European Fusion Energy Agreement (EFDA)....

  10. An MRI system for imaging neonates in the NICU: initial feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Tkach, Jean A.; Loew, Wolfgang; Pratt, Ron G.; Daniels, Barret R.; Giaquinto, Randy O.; Winter, Patrick M.; Li, Yu; Dumoulin, Charles L. [Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Department of Radiology, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Hillman, Noah H.; Jobe, Alan H.; Kallapur, Suhas G.; Merhar, Stephanie L.; Ikegami, Machiko; Whitsett, Jeffrey A. [Perinatal Institute, Cincinnati Children' s Hospital Medical Center, Division of Neonatology and Pulmonary Biology, Cincinnati, OH (United States); Kline-Fath, Beth M. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2012-11-15

    Transporting premature infants from a neonatal intensive care unit (NICU) to a radiology department for MRI has medical risks and logistical challenges. To develop a small 1.5-T MRI system for neonatal imaging that can be easily installed in the NICU and to evaluate its performance using a sheep model of human prematurity. A 1.5-T MRI system designed for orthopedic use was adapted for neonatal imaging. The system was used for MRI examinations of the brain, chest and abdomen in 12 premature lambs during the first hours of life. Spin-echo, fast spin-echo and gradient-echo MR images were evaluated by two pediatric radiologists. All animals remained physiologically stable throughout the imaging sessions. Animals were imaged at two or three time points. Seven brain MRI examinations were performed in seven different animals, 23 chest examinations in 12 animals and 19 abdominal examinations in 11 animals. At each anatomical location, high-quality images demonstrating good spatial resolution, signal-to-noise ratio and tissue contrast were routinely obtained within 30 min using standard clinical protocols. Our preliminary experience demonstrates the feasibility and potential of the neonatal MRI system to provide state-of-the-art MRI capabilities within the NICU. Advantages include overall reduced cost and site demands, lower acoustic noise, improved ease of access and reduced medical risk to the neonate. (orig.)

  11. An MRI system for imaging neonates in the NICU: initial feasibility study

    International Nuclear Information System (INIS)

    Tkach, Jean A.; Loew, Wolfgang; Pratt, Ron G.; Daniels, Barret R.; Giaquinto, Randy O.; Winter, Patrick M.; Li, Yu; Dumoulin, Charles L.; Hillman, Noah H.; Jobe, Alan H.; Kallapur, Suhas G.; Merhar, Stephanie L.; Ikegami, Machiko; Whitsett, Jeffrey A.; Kline-Fath, Beth M.

    2012-01-01

    Transporting premature infants from a neonatal intensive care unit (NICU) to a radiology department for MRI has medical risks and logistical challenges. To develop a small 1.5-T MRI system for neonatal imaging that can be easily installed in the NICU and to evaluate its performance using a sheep model of human prematurity. A 1.5-T MRI system designed for orthopedic use was adapted for neonatal imaging. The system was used for MRI examinations of the brain, chest and abdomen in 12 premature lambs during the first hours of life. Spin-echo, fast spin-echo and gradient-echo MR images were evaluated by two pediatric radiologists. All animals remained physiologically stable throughout the imaging sessions. Animals were imaged at two or three time points. Seven brain MRI examinations were performed in seven different animals, 23 chest examinations in 12 animals and 19 abdominal examinations in 11 animals. At each anatomical location, high-quality images demonstrating good spatial resolution, signal-to-noise ratio and tissue contrast were routinely obtained within 30 min using standard clinical protocols. Our preliminary experience demonstrates the feasibility and potential of the neonatal MRI system to provide state-of-the-art MRI capabilities within the NICU. Advantages include overall reduced cost and site demands, lower acoustic noise, improved ease of access and reduced medical risk to the neonate. (orig.)

  12. An MRI system for imaging neonates in the NICU: initial feasibility study.

    Science.gov (United States)

    Tkach, Jean A; Hillman, Noah H; Jobe, Alan H; Loew, Wolfgang; Pratt, Ron G; Daniels, Barret R; Kallapur, Suhas G; Kline-Fath, Beth M; Merhar, Stephanie L; Giaquinto, Randy O; Winter, Patrick M; Li, Yu; Ikegami, Machiko; Whitsett, Jeffrey A; Dumoulin, Charles L

    2012-11-01

    Transporting premature infants from a neonatal intensive care unit (NICU) to a radiology department for MRI has medical risks and logistical challenges. To develop a small 1.5-T MRI system for neonatal imaging that can be easily installed in the NICU and to evaluate its performance using a sheep model of human prematurity. A 1.5-T MRI system designed for orthopedic use was adapted for neonatal imaging. The system was used for MRI examinations of the brain, chest and abdomen in 12 premature lambs during the first hours of life. Spin-echo, fast spin-echo and gradient-echo MR images were evaluated by two pediatric radiologists. All animals remained physiologically stable throughout the imaging sessions. Animals were imaged at two or three time points. Seven brain MRI examinations were performed in seven different animals, 23 chest examinations in 12 animals and 19 abdominal examinations in 11 animals. At each anatomical location, high-quality images demonstrating good spatial resolution, signal-to-noise ratio and tissue contrast were routinely obtained within 30 min using standard clinical protocols. Our preliminary experience demonstrates the feasibility and potential of the neonatal MRI system to provide state-of-the-art MRI capabilities within the NICU. Advantages include overall reduced cost and site demands, lower acoustic noise, improved ease of access and reduced medical risk to the neonate.

  13. WE-EF-BRD-02: Battling Maxwell’s Equations: Physics Challenges and Solutions for Hybrid MRI Systems

    Energy Technology Data Exchange (ETDEWEB)

    Keall, P. [University of Sydney (Australia)

    2015-06-15

    MRI-guided treatment is a growing area of medicine, particularly in radiotherapy and surgery. The exquisite soft tissue anatomic contrast offered by MRI, along with functional imaging, makes the use of MRI during therapeutic procedures very attractive. Challenging the utility of MRI in the therapy room are many issues including the physics of MRI and the impact on the environment and therapeutic instruments, the impact of the room and instruments on the MRI; safety, space, design and cost. In this session, the applications and challenges of MRI-guided treatment will be described. The session format is: Past, present and future: MRI-guided radiotherapy from 2005 to 2025: Jan Lagendijk Battling Maxwell’s equations: Physics challenges and solutions for hybrid MRI systems: Paul Keall I want it now!: Advances in MRI acquisition, reconstruction and the use of priors to enable fast anatomic and physiologic imaging to inform guidance and adaptation decisions: Yanle Hu MR in the OR: The growth and applications of MRI for interventional radiology and surgery: Rebecca Fahrig Learning Objectives: To understand the history and trajectory of MRI-guided radiotherapy To understand the challenges of integrating MR imaging systems with linear accelerators To understand the latest in fast MRI methods to enable the visualisation of anatomy and physiology on radiotherapy treatment timescales To understand the growing role and challenges of MRI for image-guided surgical procedures My disclosures are publicly available and updated at: http://sydney.edu.au/medicine/radiation-physics/about-us/disclosures.php.

  14. WE-EF-BRD-02: Battling Maxwell’s Equations: Physics Challenges and Solutions for Hybrid MRI Systems

    International Nuclear Information System (INIS)

    Keall, P.

    2015-01-01

    MRI-guided treatment is a growing area of medicine, particularly in radiotherapy and surgery. The exquisite soft tissue anatomic contrast offered by MRI, along with functional imaging, makes the use of MRI during therapeutic procedures very attractive. Challenging the utility of MRI in the therapy room are many issues including the physics of MRI and the impact on the environment and therapeutic instruments, the impact of the room and instruments on the MRI; safety, space, design and cost. In this session, the applications and challenges of MRI-guided treatment will be described. The session format is: Past, present and future: MRI-guided radiotherapy from 2005 to 2025: Jan Lagendijk Battling Maxwell’s equations: Physics challenges and solutions for hybrid MRI systems: Paul Keall I want it now!: Advances in MRI acquisition, reconstruction and the use of priors to enable fast anatomic and physiologic imaging to inform guidance and adaptation decisions: Yanle Hu MR in the OR: The growth and applications of MRI for interventional radiology and surgery: Rebecca Fahrig Learning Objectives: To understand the history and trajectory of MRI-guided radiotherapy To understand the challenges of integrating MR imaging systems with linear accelerators To understand the latest in fast MRI methods to enable the visualisation of anatomy and physiology on radiotherapy treatment timescales To understand the growing role and challenges of MRI for image-guided surgical procedures My disclosures are publicly available and updated at: http://sydney.edu.au/medicine/radiation-physics/about-us/disclosures.php

  15. Characterization of acoustic noise in a neonatal intensive care unit MRI system

    Energy Technology Data Exchange (ETDEWEB)

    Tkach, Jean A.; Li, Yu; Pratt, Ronald G.; Loew, Wolfgang; Daniels, Barret R.; Giaquinto, Randy O.; Dumoulin, Charles L. [Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Department of Radiology, Cincinnati, OH (United States); Baroch, Kelly A. [Cincinnati Children' s Hospital Medical Center, Division of Audiology, Cincinnati, OH (United States); Merhar, Stephanie L. [Cincinnati Children' s Hospital Medical Center, Division of Neonatology and Pulmonary Biology, Perinatal Institute, Cincinnati, OH (United States); Kline-Fath, Beth M. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2014-08-15

    To eliminate the medical risks and logistical challenges of transporting infants from the neonatal intensive care unit (NICU) to the radiology department for magnetic resonance imaging, a small-footprint 1.5-T MRI scanner has been developed for neonatal imaging within the NICU. MRI is known to be noisy, and exposure to excessive acoustic noise has the potential to elicit physiological distress and impact development in the term and preterm infant. To measure and compare the acoustic noise properties of the NICU MRI system against those of a conventional 1.5-T MRI system. We performed sound pressure level measurements in the NICU MRI scanner and in a conventional adult-size whole-body 1.5-T MRI system. Sound pressure level measurements were made for six standard clinical MR imaging protocols. The average sound pressure level value, reported in unweighted (dB) and A-weighted (dBA) decibels for all six imaging pulse sequences, was 73.8 dB and 88 dBA for the NICU scanner, and 87 dB and 98.4 dBA for the conventional MRI scanner. The sound pressure level values measured on the NICU scanner for each of the six MR imaging pulse sequences were consistently and significantly (P = 0.03) lower, with an average difference of 14.2 dB (range 10-21 dB) and 11 dBA (range 5-18 dBA). The sound pressure level frequency response of the two MR systems showed a similar harmonic structure above 200 Hz for all imaging sequences. The amplitude, however, was appreciably lower for the NICU scanner, by as much as 30 dB, for frequencies below 200 Hz. The NICU MRI system is quieter than conventional MRI scanners, improving safety for the neonate and facilitating siting of the unit within the NICU. (orig.)

  16. Characterization of acoustic noise in a neonatal intensive care unit MRI system

    International Nuclear Information System (INIS)

    Tkach, Jean A.; Li, Yu; Pratt, Ronald G.; Loew, Wolfgang; Daniels, Barret R.; Giaquinto, Randy O.; Dumoulin, Charles L.; Baroch, Kelly A.; Merhar, Stephanie L.; Kline-Fath, Beth M.

    2014-01-01

    To eliminate the medical risks and logistical challenges of transporting infants from the neonatal intensive care unit (NICU) to the radiology department for magnetic resonance imaging, a small-footprint 1.5-T MRI scanner has been developed for neonatal imaging within the NICU. MRI is known to be noisy, and exposure to excessive acoustic noise has the potential to elicit physiological distress and impact development in the term and preterm infant. To measure and compare the acoustic noise properties of the NICU MRI system against those of a conventional 1.5-T MRI system. We performed sound pressure level measurements in the NICU MRI scanner and in a conventional adult-size whole-body 1.5-T MRI system. Sound pressure level measurements were made for six standard clinical MR imaging protocols. The average sound pressure level value, reported in unweighted (dB) and A-weighted (dBA) decibels for all six imaging pulse sequences, was 73.8 dB and 88 dBA for the NICU scanner, and 87 dB and 98.4 dBA for the conventional MRI scanner. The sound pressure level values measured on the NICU scanner for each of the six MR imaging pulse sequences were consistently and significantly (P = 0.03) lower, with an average difference of 14.2 dB (range 10-21 dB) and 11 dBA (range 5-18 dBA). The sound pressure level frequency response of the two MR systems showed a similar harmonic structure above 200 Hz for all imaging sequences. The amplitude, however, was appreciably lower for the NICU scanner, by as much as 30 dB, for frequencies below 200 Hz. The NICU MRI system is quieter than conventional MRI scanners, improving safety for the neonate and facilitating siting of the unit within the NICU. (orig.)

  17. [Mechanical Shimming Method and Implementation for Permanent Magnet of MRI System].

    Science.gov (United States)

    Xue, Tingqiang; Chen, Jinjun

    2015-03-01

    A mechanical shimming method and device for permanent magnet of MRI system has been developed to meet its stringent homogeneity requirement without time-consuming passive shimming on site, installation and adjustment efficiency has been increased.

  18. 4 Tesla Whole Body MRI MRSI System for Investigation of Neurodegenerative Diseases

    National Research Council Canada - National Science Library

    Weiner, Michael W

    2004-01-01

    The overall long-term goal of imaging research to be performed with this 4 Tesla Siemens/Bruker MRI system is the development of improved diagnostic methods for accurate detection of neurodegenerative...

  19. Energy Systems Integration News - October 2016 | Energy Systems Integration

    Science.gov (United States)

    Facility | NREL October 2016 Energy Systems Integration News A monthly recap of the latest energy systems integration (ESI) developments at NREL and around the world. Subscribe Archives October Integration Facility's main control room. OMNETRIC Group Demonstrates a Distributed Control Hierarchy for

  20. Stochastic Energy Deployment System

    Energy Technology Data Exchange (ETDEWEB)

    2011-11-30

    SEDS is an economy-wide energy model of the U.S. The model captures dynamics between supply, demand, and pricing of the major energy types consumed and produced within the U.S. These dynamics are captured by including: the effects of macroeconomics; the resources and costs of primary energy types such as oil, natural gas, coal, and biomass; the conversion of primary fuels into energy products like petroleum products, electricity, biofuels, and hydrogen; and lastly the end- use consumption attributable to residential and commercial buildings, light and heavy transportation, and industry. Projections from SEDS extend to the year 2050 by one-year time steps and are generally projected at the national level. SEDS differs from other economy-wide energy models in that it explicitly accounts for uncertainty in technology, markets, and policy. SEDS has been specifically developed to avoid the computational burden, and sometimes fruitless labor, that comes from modeling significantly low-level details. Instead, SEDS focuses on the major drivers within the energy economy and evaluates the impact of uncertainty around those drivers.

  1. Testing the quality of images for permanent magnet desktop MRI systems using specially designed phantoms.

    Science.gov (United States)

    Qiu, Jianfeng; Wang, Guozhu; Min, Jiao; Wang, Xiaoyan; Wang, Pengcheng

    2013-12-21

    Our aim was to measure the performance of desktop magnetic resonance imaging (MRI) systems using specially designed phantoms, by testing imaging parameters and analysing the imaging quality. We designed multifunction phantoms with diameters of 18 and 60 mm for desktop MRI scanners in accordance with the American Association of Physicists in Medicine (AAPM) report no. 28. We scanned the phantoms with three permanent magnet 0.5 T desktop MRI systems, measured the MRI image parameters, and analysed imaging quality by comparing the data with the AAPM criteria and Chinese national standards. Image parameters included: resonance frequency, high contrast spatial resolution, low contrast object detectability, slice thickness, geometrical distortion, signal-to-noise ratio (SNR), and image uniformity. The image parameters of three desktop MRI machines could be measured using our specially designed phantoms, and most parameters were in line with MRI quality control criterion, including: resonance frequency, high contrast spatial resolution, low contrast object detectability, slice thickness, geometrical distortion, image uniformity and slice position accuracy. However, SNR was significantly lower than in some references. The imaging test and quality control are necessary for desktop MRI systems, and should be performed with the applicable phantom and corresponding standards.

  2. MRI system scoring for differentiation of malignant versus benign stricture of the common bile duct

    Directory of Open Access Journals (Sweden)

    Savastano S

    2016-11-01

    Full Text Available The purpose of this study was to evaluate the ability of magnetic resonance imaging (MRI to differentiate between malignant and benign strictures of the common bile duct by using a scoring system. MRI scans of 34 patients with indeterminate biliary stricture on prior imaging were reviewed; non-enhanced MRI, magnetic resonance cholangiopancreatography (MRCP, diffusion weighted imaging, and contrast-enhanced MRIs were considered for analysis. Ten radiologic findings were significant for malignancy: luminal irregularity, post-contrast conspicuity, high signal intensity on diffusion weighted MRI, luminal stenosis asymmetry, T2-weighted MRI signal intensity, indistinct outer border, abrupt stenosis, bile duct dilatation ≥ 12.5 mm, stenosis length ≥ 10.5 mm, and wall thickness ≥ 4.5 mm. Since none of these findings was pathognomonic for malignancy, a simple system scoring based on statistically significant findings was developed, where each of the above findings counts for one point. A score of 6 or higher was found only in patients with a malignant stricture of the common bile duct; 70% of patients with a benign stenosis had a score of 1, or 2, and all patients with benign lesions had scores of less than 5. This MRI scoring system can assist in the differential diagnosis of common bile duct stricture with high accuracy; to be widely applicable, the MRI score needs to be validated in a prospective patient population.

  3. Testing the quality of images for permanent magnet desktop MRI systems using specially designed phantoms

    International Nuclear Information System (INIS)

    Qiu, Jianfeng; Wang, Guozhu; Min, Jiao; Wang, Xiaoyan; Wang, Pengcheng

    2013-01-01

    Our aim was to measure the performance of desktop magnetic resonance imaging (MRI) systems using specially designed phantoms, by testing imaging parameters and analysing the imaging quality. We designed multifunction phantoms with diameters of 18 and 60 mm for desktop MRI scanners in accordance with the American Association of Physicists in Medicine (AAPM) report no. 28. We scanned the phantoms with three permanent magnet 0.5 T desktop MRI systems, measured the MRI image parameters, and analysed imaging quality by comparing the data with the AAPM criteria and Chinese national standards. Image parameters included: resonance frequency, high contrast spatial resolution, low contrast object detectability, slice thickness, geometrical distortion, signal-to-noise ratio (SNR), and image uniformity. The image parameters of three desktop MRI machines could be measured using our specially designed phantoms, and most parameters were in line with MRI quality control criterion, including: resonance frequency, high contrast spatial resolution, low contrast object detectability, slice thickness, geometrical distortion, image uniformity and slice position accuracy. However, SNR was significantly lower than in some references. The imaging test and quality control are necessary for desktop MRI systems, and should be performed with the applicable phantom and corresponding standards. (paper)

  4. Piezoelectrically Actuated Robotic System for MRI-Guided Prostate Percutaneous Therapy

    OpenAIRE

    Su, Hao; Shang, Weijian; Cole, Gregory; Li, Gang; Harrington, Kevin; Camilo, Alexander; Tokuda, Junichi; Tempany, Clare M.; Hata, Nobuhiko; Fischer, Gregory S.

    2014-01-01

    This paper presents a fully-actuated robotic system for percutaneous prostate therapy under continuously acquired live magnetic resonance imaging (MRI) guidance. The system is composed of modular hardware and software to support the surgical workflow of intra-operative MRI-guided surgical procedures. We present the development of a 6-degree-of-freedom (DOF) needle placement robot for transperineal prostate interventions. The robot consists of a 3-DOF needle driver module and a 3-DOF Cartesian...

  5. Desmoid fibromatosis: MRI features of response to systemic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sheth, Pooja J.; Subhawong, Ty K. [University of Miami Miller School of Medicine/Jackson Memorial Hospital, Department of Radiology, Miami, FL (United States); Del Moral, Spencer; Wilky, Breelyn A.; Trent, Jonathan C. [University of Miami Miller School of Medicine/Sylvester Comprehensive Cancer Center, Division of Hematology/Oncology, Department of Medicine, Miami, FL (United States); Cohen, Jonathan [Oncology and Radiation Associates, Miami, FL (United States); Rosenberg, Andrew E. [University of Miami Miller School of Medicine, Department of Pathology, Miami, FL (United States); Temple, H.T. [Center for Orthopedic Innovations, Miami, FL (United States)

    2016-10-15

    Imaging criteria for measuring the response of desmoid fibromatosis to systemic therapy are not well established. We evaluated a series of patients with desmoids who underwent systemic therapy to document magnetic resonance imaging (MRI) features associated with a positive clinical response. This Institutional Review Board-approved retrospective study included 23 patients (mean age 40.5) with 29 extra-abdominal tumors. Therapeutic regimens included cytotoxic chemotherapy (n = 19), targeted therapy (n = 3), and nonsteroid anti-inflammatory drugs (NSAIDS; n = 1). Clinical effects were categorized as progressive disease, stable, or partial response. Maximum tumor dimension (D{sub max}), approximate tumor volume (V{sub Tumor}), and quantitative tumor T2 hyperintensity and contrast enhancement (relative to muscle) for pre- and post-treatment MRIs were compared. Three lesions progressed, 5 lesions were stable, whereas 21 showed a clinical response. D{sub max} decreased more in responders (mean -11.0 %) than in stable/progressive lesions (mean -3.6 and 0 % respectively, p = 0.28, ANOVA); by Response Evaluation Criteria in Solid Tumors (RECIST 1.1) 27 out of 29 lesions were ''stable,'' including the 3 progressive lesions. In responders, V{sub Tumor} change averaged -29.4 %, but -19.2 % and +32.5 % in stable and progressive lesions respectively (p = 0.002, ANOVA); by 3D criteria 14 out of 29 lesions showed a partial response. T2 hyperintensity decreased by 50-54 % in partial response/stable disease, but only by 10 % in progressive lesions (p = 0.049, t test). Changes in contrast enhancement ranged from -23 % to 0 %, but were not statistically significant among response groups (p = 0.37). Change in T2 hyperintensity showed a positive correlation with volumetric change (r = 0.40). Decreases in volume and T2 hyperintensity reflect the positive response of desmoid fibromatosis to systemic therapy; RECIST 1.1 criteria are not sensitive to clinically

  6. Energy policies and renewable energy systems monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Di Nisio, Attilio; Savino, Mario; Spadavecchia, Maurizio [Electrical and Electronic Measurements Laboratory, Dept. of Electrical and Electronic Engineering - Politecnico di Bari, Bari (Italy)], e-mails: dinisio@misure.poliba.it, savino@misure.poliba.it, spadavecchia@misure.poliba.it

    2011-07-01

    Full text: The global energy crisis is forcing every country worldwide to review its policies on energy. The environmental disaster at Japan's Fukushima Daiichi nuclear power plant has accelerated this process. Many people around the world are citing the disaster as evidence that nuclear power would endanger the survival of mankind on earth and should be banned. Today we need to focus more substantially on energy saving, especially using smart devices with low power consumption. We have also to review the approach to the exploitation of energy and move from a philosophy 'from the ground to the subsurface' to another 'from the earth to the sun'. This paper highlights the increasing importance of solar power in meeting energy needs while achieving security of supply and minimising carbon dioxide (CO{sub 2}) emissions. It deals also with the development of solar power plants, which require a supervisory control system that improves their efficiency and reliability. (author)

  7. Sustainable Energy Systems and Applications

    CERN Document Server

    Dinçer, İbrahim

    2012-01-01

    Sustainable Energy Systems and Applications presents analyses of sustainable energy systems and their applications, providing new understandings, methodologies, models and applications along with descriptions of several illustrative examples and case studies. This textbook aims to address key pillars in the field, such as: better efficiency, cost effectiveness, use of energy resources, environment, energy security, and sustainable development. It also includes some cutting-edge topics, such as hydrogen and fuel cells, renewable, clean combustion technologies, CO2 abatement technologies, and some potential tools for design, analysis and performance improvement. The book also: Discusses producing energy by increasing systems efficiency in generation, conversion, transportation and consumption Analyzes the conversion of fossil fuels to clean fuels for limiting  pollution and creating a better environment Sustainable Energy Systems and Applications is a research-based textbook which can be used by senior u...

  8. Energy management systems in buildings

    Energy Technology Data Exchange (ETDEWEB)

    Lush, D. M.

    1979-07-01

    An investigation is made of the range of possibilities available from three types of systems (automatic control devices, building envelope, and the occupants) in buildings. The following subjects are discussed: general (buildings, design and personnel); new buildings (envelope, designers, energy and load calculations, plant design, general design parameters); existing buildings (conservation measures, general energy management, air conditioned buildings, industrial buildings); man and motivation (general, energy management and documentation, maintenance, motivation); automatic energy management systems (thermostatic controls, optimized plant start up, air conditioned and industrial buildings, building automatic systems). (MCW)

  9. Battery energy storage system

    NARCIS (Netherlands)

    Tol, C.S.P.; Evenblij, B.H.

    2009-01-01

    The ability to store electrical energy adds several interesting features to a ships distribution network, as silent power, peak shaving and a ride through in case of generator failure. Modern intrinsically safe Li-ion batteries bring these within reach. For this modern lithium battery applications

  10. Primary Central Nervous System Lymphoma: Incorporating MRI in the Planning of Treatment Strategies

    International Nuclear Information System (INIS)

    Eloraby, A.; Zaki, I.

    2001-01-01

    Primary lymphoma of the central nervous system is becoming increasingly encountered secondary to the acquired immune-deficiency disorders. MRI is rapidly evolving diagnostic tool in the management of the lymphomatous CNS primary infiltrates. Methods and materials: 40 patients of the National Cancer Institute of Cairo University were studied by medium and high power MRI machines before and after intra-venous contrast enhancement. Results: The cerebral lesions exhibited specific diagnostic criteria regarding the anatomical configuration, signal pattern, peri-focal oedema and response to steroids, such manifestations made. Conclusion: MRI a highly reliable tool in the management of the disease. The work proved that spinal cord primary lymphoma is a rare entity

  11. Decarbonization of Croatian Energy System

    International Nuclear Information System (INIS)

    Potocnik, V.

    2012-01-01

    Energy system decarbonization is reduction of greenhouse gases (CO 2 ) emission, chiefly from the fossil fuels (coal, oil, natural gas) combustion. The main objective of an energy system decarbonization is the climate change mitigation, and at the same time development of local industry and employment, better environment and health protection, as well as reduction of the fossil fuels import and foreign debt. Croatia has small fossil fuels reserves and large renewable energy sources (RES) reserves, energy efficiency (ENEF) is relatively low, and energy import, according to the actual Energy strategy 2009, should increase from 50% to 70% until 2020. Croatian energy system participates with about one third in the Croatian foreign trade deficit. The main measures of the Croatian energy system decarbonization should be: increasing ENEF (energy savings), switch from fossil fuels to RES, administrative measures (low carbon development strategy, environmental tax reform, and decoupling income from energy sales). By urgent application of these measures, Croatia could become fossil fuels free until the year 2050.(author)

  12. Integrated energy systems and local energy markets

    International Nuclear Information System (INIS)

    Lund, Henrik; Muenster, Ebbe

    2006-01-01

    Significant benefits are connected with an increase in the flexibility of the Danish energy system. On the one hand, it is possible to benefit from trading electricity with neighbouring countries, and on the other, Denmark will be able to make better use of wind power and other types of renewable energy in the future. This paper presents the analysis of different ways of increasing flexibility in the Danish energy system by the use of local regulation mechanisms. This strategy is compared with the opposite extreme, i.e. trying to solve all balancing problems via electricity trade on the international market. The conclusion is that it is feasible for the Danish society to include the CHP plants in the balancing of fluctuating wind power. There are major advantages in equipping small CHP plants as well as the large CHP plants with heat pumps. By doing so, it will be possible to increase the share of wind power from the present 20 to 40% without causing significant problems of imbalance between electricity consumption and production. Investment in increased flexibility is in itself profitable. Furthermore, the feasibility of wind power is improved

  13. Clinical evaluation of shoulder kinematic MRI using an open-type system

    International Nuclear Information System (INIS)

    Ohno, Seiichiro; Togami, Izumi; Sasai, Nobuya

    2000-01-01

    Previous studies on kinematic MRI of the shoulder using cylindrical-type MRI systems were limited to internal or external rotation. The open-type MRI system enables kinematic MRI to be carried out for the abductive position, and is expected to permit evaluation of the superior and inferior glenoid labrum. It is important to evaluate the superior and inferior glenoid labrum in cases of sports injuries (baseball, tennis, etc.). We evaluated the superior and inferior glenoid labrum for abductive motion in asymptomatic healthy volunteers as a preliminary study. As the abduction angle increased, the superior labrum moved into the joint space. Its shape changed from round or triangular to crescent (p<0.0001), and there was increased signal for larger abduction angles (p<0.0001). On the other hand, the shape of the inferior labrum tended to change from crescent to triangular or round (p<0.0001). Increased signal was seen in the inferior labrum on about half the shoulders (N.P.). This did not change as the abduction angle increased. Our results define normal patterns for the superior and inferior glenoid labrum on abductive kinematic MRI in healthy volunteers. Abductive kinematic studies using an open-type MRI system, which permits dynamic evaluation of the superior and inferior glenoid labrum, are expected to be useful for various patients with sports injuries. (author)

  14. Respiratory motion-resolved, self-gated 4D-MRI using Rotating Cartesian K-space (ROCK): Initial clinical experience on an MRI-guided radiotherapy system.

    Science.gov (United States)

    Han, Fei; Zhou, Ziwu; Du, Dongsu; Gao, Yu; Rashid, Shams; Cao, Minsong; Shaverdian, Narek; Hegde, John V; Steinberg, Michael; Lee, Percy; Raldow, Ann; Low, Daniel A; Sheng, Ke; Yang, Yingli; Hu, Peng

    2018-06-01

    To optimize and evaluate the respiratory motion-resolved, self-gated 4D-MRI using Rotating Cartesian K-space (ROCK-4D-MRI) method in a 0.35 T MRI-guided radiotherapy (MRgRT) system. The study included seven patients with abdominal tumors treated on the MRgRT system. ROCK-4D-MRI and 2D-CINE, was performed immediately after one of the treatment fractions. Motion quantification based on 4D-MRI was compared with those based on 2D-CINE. The image quality of 4D-MRI was evaluated against 4D-CT. The gross tumor volumes (GTV) were defined based on individual respiratory phases of both 4D-MRI and 4D-CT and compared for their variability over the respiratory cycle. The motion measurements based on 4D-MRI matched well with 2D-CINE, with differences of 1.04 ± 0.52 mm in the superior-inferior and 0.54 ± 0.21 mm in the anterior-posterior directions. The image quality scores of 4D-MRI were significantly higher than 4D-CT, with better tumor contrast (3.29 ± 0.76 vs. 1.86 ± 0.90) and less motion artifacts (3.57 ± 0.53 vs. 2.29 ± 0.95). The GTVs were more consistent in 4D-MRI than in 4D-CT, with significantly smaller GTV variability (9.31 ± 4.58% vs. 34.27 ± 23.33%). Our study demonstrated the clinical feasibility of using the ROCK-4D-MRI to acquire high quality, respiratory motion-resolved 4D-MRI in a low-field MRgRT system. The 4D-MRI image could provide accurate dynamic information for radiotherapy treatment planning. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Principles of sustainable energy systems

    CERN Document Server

    Kreith, Frank

    2013-01-01

    … ""This is an ideal book for seniors and graduate students interested in learning about the sustainable energy field and its penetration. The authors provide very strong discussion on cost-benefit analysis and ROI calculations for various alternate energy systems in current use. This is a descriptive book with detailed case-based analyses of various systems and engineering applications. The text book provides real-world case studies and related problems pertaining to sustainable energy systems.""--Dr. Kuruvilla John, University of North Texas""The new edition of ""Principles of Sustainable En

  16. Energy transfer in plasmonic systems

    International Nuclear Information System (INIS)

    Pustovit, Vitaliy N; Urbas, Augustine M; Shahbazyan, Tigran V

    2014-01-01

    We present our results on energy transfer between donor and acceptor molecules or quantum dots near a plasmonic nanoparticle. In such systems, the Förster resonance energy transfer is strongly modified due to plasmon-mediated coupling between donors and acceptors. The transfer efficiency is determined by a competition between transfer, radiation and dissipation that depends sensitively on system parameters. When donor and accepror spectral bands overlap with dipole surface plasmon resonance, the dominant transfer mechanism is through plasmon-enhanced radiative coupling. When transfer takes place from an ensemble of donors to an acceptor, a cooperative amplification of energy transfer takes place in a wide range of system parameters. (paper)

  17. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Kreutz, T.G.; Steinbugler, M. [Princeton Univ., NJ (United States)] [and others

    1996-10-01

    In this report the authors describe results from technical and economic assessments carried out during the past year with support from the USDOE Hydrogen R&D Program. (1) Assessment of technologies for small scale production of hydrogen from natural gas. Because of the cost and logistics of transporting and storing hydrogen, it may be preferable to produce hydrogen at the point of use from more readily available energy carriers such as natural gas or electricity. In this task the authors assess near term technologies for producing hydrogen from natural gas at small scale including steam reforming, partial oxidation and autothermal reforming. (2) Case study of developing a hydrogen vehicle refueling infrastructure in Southern California. Many analysts suggest that the first widespread use of hydrogen energy is likely to be in zero emission vehicles in Southern California. Several hundred thousand zero emission automobiles are projected for the Los Angeles Basin alone by 2010, if mandated levels are implemented. Assuming that hydrogen vehicles capture a significant fraction of this market, a large demand for hydrogen fuel could evolve over the next few decades. Refueling a large number of hydrogen vehicles poses significant challenges. In this task the authors assess near term options for producing and delivering gaseous hydrogen transportation fuel to users in Southern California including: (1) hydrogen produced from natural gas in a large, centralized steam reforming plant, and delivered to refueling stations via liquid hydrogen truck or small scale hydrogen gas pipeline, (2) hydrogen produced at the refueling station via small scale steam reforming of natural gas, (3) hydrogen produced via small scale electrolysis at the refueling station, and (4) hydrogen from low cost chemical industry sources (e.g. excess capacity in refineries which have recently upgraded their hydrogen production capacity, etc.).

  18. Role of pharmacokinetic parameters derived with high temporal resolution DCE MRI using simultaneous PET/MRI system in breast cancer: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Jena, Amarnath, E-mail: drjena2002@gmail.com [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Delhi–Mathura Road, New Delhi 110076 (India); Taneja, Sangeeta; Singh, Aru; Negi, Pradeep; Mehta, Shashi Bhushan [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Delhi–Mathura Road, New Delhi 110076 (India); Sarin, Ramesh [Department of Surgical Oncology, Indraprastha Apollo Hospitals, Sarita Vihar, Delhi–Mathura Road, New Delhi 110076 (India)

    2017-01-15

    Highlights: • Simultaneous PET/MRI (with 3T MRI in the core) for quantitative pharmacokinetics. • Diagnostic accuracy of pharmacokinetic parameters like K{sup trans}, K{sub ep} and v{sub e} acquired through this system. • Incorporating high temporal resolution sequence with short acquisition time of 60 s within the routine DCE MRI in a simultaneous PET/MRI system. - Abstract: Purpose: To evaluate the reliability of pharmacokinetic parameters like K{sup trans}, Kep and v{sub e} derived through DCE MRI breast protocol using 3 T Simultaneous PET/MRI (3 Tesla Positron Emission Tomography/Magnetic Resonance Imaging) system in distinguishing benign and malignant lesions. Materials and methods: High temporal resolution DCE (Dynamic Contrast Enhancement) MRI performed as routine breast MRI for diagnosis or as a part of PET/MRI for cancer staging using a 3 T simultaneous PET/MRI system in 98 women having 109 breast lesions were analyzed for calculation of pharmacokinetic parameters (K{sup trans}, v{sub e}, and Kep) at 60 s time point using an in-house developed computation scheme. Results: Receiver operating characteristic (ROC) curve analysis revealed a cut off value for K{sup trans}, Kep, v{sub e} as 0.50, 2.59, 0.15 respectively which reliably distinguished benign and malignant breast lesions. Data analysis revealed an overall accuracy of 94.50%, 79.82% and 87.16% for K{sup trans}, Kep, v{sub e} respectively. Introduction of native T1 normalization with an externally placed phantom showed a higher accuracy (94.50%) than without native T1 normalization (93.50%) with an increase in specificity of 87% vs 84%. Conclusion: Overall the results indicate that reliable measurement of pharmacokinetic parameters with reduced acquisition time is feasible in a 3TMRI embedded PET/MRI system with reasonable accuracy and application may be extended to exploit the potential of simultaneous PET/MRI in further work on breast cancer.

  19. Photovoltaic Energy Conversion Systems

    DEFF Research Database (Denmark)

    Kouro, Samir; Wu, Bin; Abu-Rub, Haitham

    2014-01-01

    This chapter presents a comprehensive overview of grid-connected PV systems, including power curves, grid-connected configurations, different converter topologies (both single- and three-phase), control schemes, MPPT, and anti-islanding detection methods. The focus of the chapter has been on the ...

  20. Probabilistic Approaches to Energy Systems

    DEFF Research Database (Denmark)

    Iversen, Jan Emil Banning

    of renewable energy generation. Particularly we focus on producing forecasting models that can predict renewable energy generation, single user demand, and provide advanced forecast products that are needed for an efficient integration of renewable energy into the power generation mix. Such forecasts can...... integration of renewable energy.Thus forecast products should be developed in unison with the decision making tool as they are two sides of the same overall challenge.......Energy generation from wind and sun is increasing rapidly in many parts of the world. This presents new challenges on how to integrate this uncertain, intermittent and non-dispatchable energy source. This thesis deals with forecasting and decision making in energy systems with a large proportion...

  1. Secure Automated Microgrid Energy System

    Science.gov (United States)

    2016-12-01

    O&M Operations and Maintenance PSO Power System Optimization PV Photovoltaic RAID Redundant Array of Independent Disks RBAC Role...elements of the initial study and operational power system model (feeder size , protective devices, generation sources, controllable loads, transformers...EW-201340) Secure Automated Microgrid Energy System December 2016 This document has been cleared for public release; Distribution Statement A

  2. Electrical Energy Storage for Renewable Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Helms, C. R. [Univ. of Texas, Dallas, TX (United States); Cho, K. J. [Univ. of Texas, Dallas, TX (United States); Ferraris, John [Univ. of Texas, Dallas, TX (United States); Balkus, Ken [Univ. of Texas, Dallas, TX (United States); Chabal, Yves [Univ. of Texas, Dallas, TX (United States); Gnade, Bruce [Univ. of Texas, Dallas, TX (United States); Rotea, Mario [Univ. of Texas, Dallas, TX (United States); Vasselli, John [Univ. of Texas, Dallas, TX (United States)

    2012-08-31

    This program focused on development of the fundamental understanding necessary to significantly improve advanced battery and ultra-capacitor materials and systems to achieve significantly higher power and energy density on the one hand, and significantly lower cost on the other. This program spanned all the way from atomic-level theory, to new nanomaterials syntheses and characterization, to system modeling and bench-scale technology demonstration. This program not only delivered significant advancements in fundamental understanding and new materials and technology, it also showcased the power of the cross-functional, multi-disciplinary teams at UT Dallas and UT Tyler for such work. These teams are continuing this work with other sources of funding from both industry and government.

  3. The baltic states' energy system

    OpenAIRE

    Nikitaravičius, Martynas

    2006-01-01

    THE BALTIC STATES’ ENERGY SYSTEM SUMMARY The goal of paper – the comparative analysis of Baltic states‘ (i.e. of Lithuania, Latvia, Estonia) energy systems in 1990-2004. The main causes that affected the development of Baltic states’ energetics are indicated in this work. By the method of statistical analysis, the comparative advantages of Baltic states‘ energetics are detected. Moreover, the main trends of further development of integration of Baltic states ‘ energetics into the energetics o...

  4. TEXT Energy Storage System

    International Nuclear Information System (INIS)

    Weldon, W.F.; Rylander, H.G.; Woodson, H.H.

    1977-01-01

    The Texas Experimental Tokamak (TEXT) Enery Storage System, designed by the Center for Electromechanics (CEM), consists of four 50 MJ, 125 V homopolar generators and their auxiliaries and is designed to power the toroidal and poloidal field coils of TEXT on a two-minute duty cycle. The four 50 MJ generators connected in series were chosen because they represent the minimum cost configuration and also represent a minimal scale up from the successful 5.0 MJ homopolar generator designed, built, and operated by the CEM

  5. Energy Systems Integration News | Energy Systems Integration Facility |

    Science.gov (United States)

    determine how well a solar photovoltaic (PV) system with battery energy storage can provide backup power to . These analyses will result in a design guide for climate-specific sizing of the system. NREL's Erfan , feasibility, and operational analyses for photovoltaic and concentrating solar power generation projects

  6. Energy Monitoring System Berbasis Web

    Directory of Open Access Journals (Sweden)

    Novan Zulkarnain

    2013-12-01

    Full Text Available Government through the Ministry of Energy and Mineral Resources (ESDM encourages the energy savings at whole buildings in Indonesia. Energy Monitoring System (EMS is a web-based solution to monitor energy usage in a building. The research methods used are the analysis, prototype design and testing. EMSconsists of hardware which consists of electrical sensors, temperature-humidity sensor, and a computer. Data on EMS are designed using Modbus protocol, stored in MySQL database application, and displayed on charts through Dashboard on LED TV using PHP programming.

  7. Innovative nuclear energy systems roadmap

    International Nuclear Information System (INIS)

    2007-12-01

    Developing nuclear energy that is sustainable, safe, has little waste by-product, and cannot be proliferated is an extremely vital and pressing issue. To resolve the four issues through free thinking and overall vision, research activities of 'innovative nuclear energy systems' and 'innovative separation and transmutation' started as a unique 21st Century COE Program for nuclear energy called the Innovative Nuclear Energy Systems for Sustainable Development of the World, COE-INES. 'Innovative nuclear energy systems' include research on CANDLE burn-up reactors, lead-cooled fast reactors and using nuclear energy in heat energy. 'Innovative separation and transmutation' include research on using chemical microchips to efficiently separate TRU waste to MA, burning or destroying waste products, or transmuting plutonium and other nuclear materials. Research on 'nuclear technology and society' and 'education' was also added in order for nuclear energy to be accepted into society. COE-INES was a five-year program ending in 2007. But some activities should be continued and this roadmap detailed them as a rough guide focusing inventions and discoveries. This technology roadmap was created for social acceptance and should be flexible to respond to changing times and conditions. (T. Tanaka)

  8. Efficiency Evaluation of Energy Systems

    CERN Document Server

    Kanoğlu, Mehmet; Dinçer, İbrahim

    2012-01-01

    Efficiency is one of the most frequently used terms in thermodynamics, and it indicates how well an energy conversion or process is accomplished. Efficiency is also one of the most frequently misused terms in thermodynamics and is often a source of misunderstanding. This is because efficiency is often used without being properly defined first. This book intends to provide a comprehensive evaluation of various efficiencies used for energy transfer and conversion systems including steady-flow energy devices (turbines, compressors, pumps, nozzles, heat exchangers, etc.), various power plants, cogeneration plants, and refrigeration systems. The book will cover first-law (energy based) and second-law (exergy based) efficiencies and provide a comprehensive understanding of their implications. It will help minimize the widespread misuse of efficiencies among students and researchers in energy field by using an intuitive and unified approach for defining efficiencies. The book will be particularly useful for a clear ...

  9. A validated clinical MRI injury scoring system in neonatal hypoxic-ischemic encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Trivedi, Shamik B.; Vesoulis, Zachary A.; Rao, Rakesh; Liao, Steve M.; Mathur, Amit M. [Washington University School of Medicine, Division of Newborn Medicine, Edward Mallinckrodt Department of Pediatrics, St. Louis, MO (United States); Shimony, Joshua S.; McKinstry, Robert C. [Washington University School of Medicine, Mallinckrodt Institute of Radiology, St. Louis, MO (United States)

    2017-10-15

    Deep nuclear gray matter injury in neonatal hypoxic-ischemic encephalopathy (HIE) is associated with worse neurodevelopmental outcomes. We previously published a qualitative MRI injury scoring system utilizing serial T1-weighted, T2-weighted and diffusion-weighted imaging (DWI), weighted for deep nuclear gray matter injury. To establish the validity of the MRI scoring system with neurodevelopmental outcome at 18-24 months. MRI scans from neonates with moderate to severe HIE treated with therapeutic hypothermia were evaluated. Signal abnormality was scored on T1-weighted, T2-weighted and DWI sequences and assessed using an established system in five regions: (a) subcortical: caudate nucleus, globus pallidus and putamen, thalamus and the posterior limb of the internal capsule; (b) white matter; (c) cortex, (d) cerebellum and (e) brainstem. MRI injury was graded as none, mild, moderate or severe. Inter-rater reliability was tested on a subset of scans by two independent and blinded neuroradiologists. Surviving infants underwent the Bayley Scales of Infant and Toddler Development-III (Bayley-III) at 18-24 months. Data were analyzed using univariate and multivariate linear and logistic regression. Fifty-seven eligible neonates underwent at least one MRI scan in the first 2 weeks of life. Mean postnatal age at scan 1 was 4±2 days in 50/57 (88%) neonates and 48/54 (89%) surviving infants underwent scan 2 at 10±2 days. In 54/57 (95%) survivors, higher MRI injury grades were significantly associated with worse outcomes in the cognitive, motor and language domains of the Bayley-III. A qualitative MRI injury scoring system weighted for deep nuclear gray matter injury is a significant predictor of neurodevelopmental outcome at 18-24 months in neonates with HIE. (orig.)

  10. A validated clinical MRI injury scoring system in neonatal hypoxic-ischemic encephalopathy

    International Nuclear Information System (INIS)

    Trivedi, Shamik B.; Vesoulis, Zachary A.; Rao, Rakesh; Liao, Steve M.; Mathur, Amit M.; Shimony, Joshua S.; McKinstry, Robert C.

    2017-01-01

    Deep nuclear gray matter injury in neonatal hypoxic-ischemic encephalopathy (HIE) is associated with worse neurodevelopmental outcomes. We previously published a qualitative MRI injury scoring system utilizing serial T1-weighted, T2-weighted and diffusion-weighted imaging (DWI), weighted for deep nuclear gray matter injury. To establish the validity of the MRI scoring system with neurodevelopmental outcome at 18-24 months. MRI scans from neonates with moderate to severe HIE treated with therapeutic hypothermia were evaluated. Signal abnormality was scored on T1-weighted, T2-weighted and DWI sequences and assessed using an established system in five regions: (a) subcortical: caudate nucleus, globus pallidus and putamen, thalamus and the posterior limb of the internal capsule; (b) white matter; (c) cortex, (d) cerebellum and (e) brainstem. MRI injury was graded as none, mild, moderate or severe. Inter-rater reliability was tested on a subset of scans by two independent and blinded neuroradiologists. Surviving infants underwent the Bayley Scales of Infant and Toddler Development-III (Bayley-III) at 18-24 months. Data were analyzed using univariate and multivariate linear and logistic regression. Fifty-seven eligible neonates underwent at least one MRI scan in the first 2 weeks of life. Mean postnatal age at scan 1 was 4±2 days in 50/57 (88%) neonates and 48/54 (89%) surviving infants underwent scan 2 at 10±2 days. In 54/57 (95%) survivors, higher MRI injury grades were significantly associated with worse outcomes in the cognitive, motor and language domains of the Bayley-III. A qualitative MRI injury scoring system weighted for deep nuclear gray matter injury is a significant predictor of neurodevelopmental outcome at 18-24 months in neonates with HIE. (orig.)

  11. Control of Solar Energy Systems

    CERN Document Server

    Camacho, Eduardo F; Rubio, Francisco R; Martínez, Diego

    2012-01-01

    Control of Solar Energy Systems details the main solar energy systems, problems involved with their control, and how control systems can help in increasing their efficiency.  After a brief introduction to the fundamental concepts associated with the use of solar energy in both photovoltaic and thermal plants, specific issues related to control of solar systems are embarked upon. Thermal energy systems are then explored in depth, as well as  other solar energy applications such as solar furnaces and solar refrigeration systems. Problems of variable generation profile and of the contribution of many solar plants to the same grid system are considered with the necessary integrated and supervisory control solutions being discussed. The text includes material on: ·         A comparison of basic and advanced control methods for parabolic troughs from PID to nonlinear model-based control; ·         solar towers and solar tracking; ·         heliostat calibration, characterization and off...

  12. Integrated roof wind energy system

    Directory of Open Access Journals (Sweden)

    Moonen S.P.G.

    2012-10-01

    Full Text Available Wind is an attractive renewable source of energy. Recent innovations in research and design have reduced to a few alternatives with limited impact on residential construction. Cost effective solutions have been found at larger scale, but storage and delivery of energy to the actual location it is used, remain a critical issue. The Integrated Roof Wind Energy System is designed to overcome the current issues of urban and larger scale renewable energy system. The system is built up by an axial array of skewed shaped funnels that make use of the Venturi Effect to accelerate the wind flow. This inventive use of shape and geometry leads to a converging air capturing inlet to create high wind mass flow and velocity toward a vertical-axis wind turbine in the top of the roof for generation of a relatively high amount of energy. The methods used in this overview of studies include an array of tools from analytical modelling, PIV wind tunnel testing, and CFD simulation studies. The results define the main design parameters for an efficient system, and show the potential for the generation of high amounts of renewable energy with a novel and effective system suited for the built environment.

  13. Energy Systems Integration Partnerships: NREL + Cogent Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Berdahl, Sonja E [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-08-09

    NREL is collaborating with Cogent Energy Systems (Cogent) to introduce small-scale waste-to-energy technology in microgrids.The focus of the project is to test and demonstrate the feasibility, reliability, and usefulness of integrating electricity generated using a simulated syngas composition matching the syngas stream to be produced by a HelioStorm-based WTE gasifier to power a microgrid as a means of addressing and complementing the intermittency of other sources of electricity.

  14. CT and MRI analysis of central nervous system Rosai-Dorfman disease

    International Nuclear Information System (INIS)

    Zhang Jiatang; Lang Senyang; Pu Chuanqiang; Zhu Ruyuan; Wang Dianjun

    2008-01-01

    Objective: To study the CT and MRI imaging features of central nervous system Rosai-Dorfman disease and to enhance knowledge and differential diagnostic ability for central nervous system Rosai-Doffman disease. Methods: The CT and MRI imaging appearances in 4 cases of pathologically proven Rosai-Dorfman disease were retrospectively evaluated and the literature of central nervous system Rosai- Dorfman disease were reviewed. Results: Two cases had cranial CT scans, 4 cases had cranial MRI scans. On CT scans, cerebral edema was demonstrated in one case and the other case was normal. MRI scans showed the lesions were solitary in saddle area in 3 cases, and multiple in anterior cranial fossa in 1 case. The lesions exhibited iso- to hypointensity on both T 1 WI and T 2 WI images. Following intravenous injection of contrast medium, ring-like enhancement was seen in 2 cases and homogeneous enhancement in 1 case. Nodular enhancement was seen in the case of multiple lesions in the anterior cranial fossa. All lesions were dural-based. Conclusions: In patients with fever, headache, elevation of the erythrocyte sedimentation rate (ESR) and a polyclonal increase in γ-globulins, the possibility of central nervous system Rosai-Dorfman disease should be considered when single or multiple dural-based mass lesions, especially in sellar region, were identified by CT and MRI. (authors)

  15. Energy-Water System Solutions | Energy Analysis | NREL

    Science.gov (United States)

    System Solutions Energy-Water System Solutions NREL has been a pioneer in the development of energy -water system solutions that explicitly address and optimize energy-water tradeoffs. NREL has evaluated energy-water system solutions for Department of Defense bases, islands, communities recovering from

  16. Turbulent Kinetic Energy Measurement Using Phase Contrast MRI for Estimating the Post-Stenotic Pressure Drop: In Vitro Validation and Clinical Application.

    Directory of Open Access Journals (Sweden)

    Hojin Ha

    Full Text Available Although the measurement of turbulence kinetic energy (TKE by using magnetic resonance imaging (MRI has been introduced as an alternative index for quantifying energy loss through the cardiac valve, experimental verification and clinical application of this parameter are still required.The goal of this study is to verify MRI measurements of TKE by using a phantom stenosis with particle image velocimetry (PIV as the reference standard. In addition, the feasibility of measuring TKE with MRI is explored.MRI measurements of TKE through a phantom stenosis was performed by using clinical 3T MRI scanner. The MRI measurements were verified experimentally by using PIV as the reference standard. In vivo application of MRI-driven TKE was explored in seven patients with aortic valve disease and one healthy volunteer. Transvalvular gradients measured by MRI and echocardiography were compared.MRI and PIV measurements of TKE are consistent for turbulent flow (0.666 400. The turbulence pressure drop correlates strongly with total TKE (R2 = 0.986. However, in vivo measurements of TKE are not consistent with the transvalvular pressure gradient estimated by echocardiography.These results suggest that TKE measurement via MRI may provide a potential benefit as an energy-loss index to characterize blood flow through the aortic valve. However, further clinical studies are necessary to reach definitive conclusions regarding this technique.

  17. Evaluation of Brain and Cervical MRI Abnormality Rates in Patients With Systemic Lupus Erythematosus With or Without Neurological Manifestations

    International Nuclear Information System (INIS)

    Harirchian, Mohammad Hossein; Saberi, Hazhir; Najafizadeh, Seyed Reza; Hashemi, Seyed Ali

    2011-01-01

    Central nervous system (CNS) involvement has been observed in 14-80% of patients with systemic lupus erythematosus (SLE). Magnetic resonance imaging (MRI) is an appropriate method for evaluating CNS involvement in these patients. Clinical manifestations and MRI findings of CNS lupus should be differentiated from other mimicking diseases such as multiple sclerosis (MS). The aim of this study was to evaluate the prevalence and extent of brain and cervical cord MRI lesions of lupus patients. The relationship between neurological signs and symptoms and MRI findings were evaluated as well. Fifty SLE patients who had been referred to the rheumatology clinic of our hospital within 2009 were included in a cross sectional study. All patients fulfilled the revised 1981 American College of Rheumatology (ACR) criteria for SLE. We evaluated the neurological signs and symptoms and brain and cervical MRI findings in these patients. Forty-one patients (82%) were female and nine (18%) were male. The mean age was 30.1 ± 9.3 years. Twenty eight (56%) patients had an abnormal brain MRI. No one showed any abnormality in the cervical MRI. The lesions in 20 patients were similar to demyelinative plaques. Seventeen patients with abnormal brain MRI were neurologically asymptomatic. There was only a significant relationship between neurological motor manifestations and brain MRI abnormal findings. Unlike the brain, cervical MRI abnormality and especially asymptomatic cord involvement in MRI is quite rare in SLE patients. This finding may be helpful to differentiate SLE from other CNS disorders such as MS

  18. Analysis of integrated energy systems

    International Nuclear Information System (INIS)

    Matsuhashi, Takaharu; Kaya, Yoichi; Komiyama, Hiroshi; Hayashi, Taketo; Yasukawa, Shigeru.

    1988-01-01

    World attention is now attracted to the concept of Novel Horizontally Integrated Energy System (NHIES). In NHIES, all fossil fuels are fist converted into CO and H 2 . Potential environmental contaminants such as sulfur are removed during this process. CO turbines are mainly used to generate electric power. Combustion is performed in pure oxygen produced through air separation, making it possible to completely prevent the formation of thermal NOx. Thus, NHIES would release very little amount of such substances that would contribute to acid rain. In this system, the intermediate energy sources of CO, H 2 and O 2 are integrated horizontally. They are combined appropriately to produce a specific form of final energy source. The integration of intermediate energy sources can provide a wide variety of final energy sources, allowing any type of fossil fuel to serve as an alternative to other types of fossil fuel. Another feature of NHIES is the positive use of nuclear fuel to reduce the formation of CO 2 . Studies are under way in Japan to develop a new concept of integrated energy system. These studies are especially aimed at decreased overall efficiency and introduction of new liquid fuels that are high in conversion efficiency. Considerations are made on the final form of energy source, robust control, acid fallout, and CO 2 reduction. (Nogami, K.)

  19. Magnetic field simulation and shimming analysis of 3.0T superconducting MRI system

    Science.gov (United States)

    Yue, Z. K.; Liu, Z. Z.; Tang, G. S.; Zhang, X. C.; Duan, L. J.; Liu, W. C.

    2018-04-01

    3.0T superconducting magnetic resonance imaging (MRI) system has become the mainstream of modern clinical MRI system because of its high field intensity and high degree of uniformity and stability. It has broad prospects in scientific research and other fields. We analyze the principle of magnet designing in this paper. We also perform the magnetic field simulation and shimming analysis of the first 3.0T/850 superconducting MRI system in the world using the Ansoft Maxwell simulation software. We guide the production and optimization of the prototype based on the results of simulation analysis. Thus the magnetic field strength, magnetic field uniformity and magnetic field stability of the prototype is guided to achieve the expected target.

  20. Renewable Energy Devices and Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Ionel, Dan M.

    2015-01-01

    In this paper, essential statistics demonstrating the increasing role of renewable energy generation are firstly discussed. A state of the art review section covers fundamentals of wind turbines and PV systems. Included are schematic diagrams illustrating the main components and system topologies...... and the fundamental and increasing role of power electronics as an enabler for renewable energy integration, and for the future power system and smart grid. Recent examples of research and development, including new devices and system installations for utility power plants, as well for as residential and commercial......, fuel cells, and storage with batteries and hydrogen, respectively. Recommended further readings on topics of electric power engineering for renewable energy are included in a final section. This paper also represents an editorial introduction for two special issues of the Electric Power Component...

  1. World energy data system (WENDS)

    International Nuclear Information System (INIS)

    Lareau, W.E.

    1979-01-01

    This paper presents a unique application of System 2000: the storage of preformatted textual information in a completely user oriented data base. The World Energy Data System is an information system which allows qualified users online access to non-classified management level data on worldwide energy technology and research and development activities. WENDS has been used to transmit up-to-date informaion on foreign energy technology and research and development programs to DOE program divisions, the Congress, and other U.S. government officials going abroad. The WENDS concept is first described. Then, the method of storage of the textual information is discussed followed by a discussion of the retrieval system which is thoroughly designed to serve the user

  2. A head-mounted display system for augmented reality: Initial evaluation for interventional MRI

    International Nuclear Information System (INIS)

    Wendt, M.; Wacker, F.K.

    2003-01-01

    Purpose: To discuss the technical details of a head mounted display with an augmented reality (AR) system and to describe a first pre-clinical evaluation in interventional MRI. Method: The AR system consists of a video-see-through head mounted display (HMD), mounted with a mini video camera for tracking and a stereo pair of mini cameras that capture live images of the scene. The live video view of the phantom/patient is augmented with graphical representations of anatomical structures from MRI image data and is displayed on the HMD. The application of the AR system with interventional MRI was tested using a MRI data set of the head and a head phantom. Results: The HMD enables the user to move around and observe the scene dynamically from various viewpoints. Within a short time the natural hand-eye coordination can easily be adapted to the slightly different view. The 3D perception is based on stereo and kinetic depth cues. A circular target with a diameter of 0.5 square centimeter was hit in 19 of 20 attempts. In a first evaluation the MRI image data augmented reality scene of a head phantom allowed good planning and precise simulation of a puncture. Conclusion: The HMD in combination with AR provides a direct, intuitive guidance for interventional MR procedures. (orig.) [de

  3. Introduction to Renewable Energy Systems

    DEFF Research Database (Denmark)

    Ma, Ke; Yang, Yongheng; Blaabjerg, Frede

    2014-01-01

    . It is concluded that as the quick development of renewable energy, wind power and PV power both show great potential to be largely integrated into the power grid. Power electronics is playing essential role in both of the systems to achieve more controllable, efficient, and reliable energy production......In this chapter, the state-of-the-arts developments of renewable energy are reviewed in respect to the installed power and market share, where wind power and photovoltaic power generation are the main focuses due to the fast growing speed and large share of installed capacity. Some basic principles...... of operation, mission profiles, as well as power electronics solutions and corresponding controls are discussed respectively in the case of wind power and photovoltaic power systems. Finally a few development trends for renewable energy conversions are also given from a power electronics point of view...

  4. Abnormal findings of magnetic resonance imaging (MRI) in patients with systemic lupus erythematosus involving the brain

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Akira; Okada, Jun; Kondo, Hirobumi (Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Medicine); Kashiwazaki, Sadao

    1992-06-01

    To elucidate the clinical significance of MRI on central nervous system systemic lupus erythematosus (CNS-SLE), MRI and CT scans were performed in 35 patients with SLE, of 18 patients who had CNS manifestations at the time of MRI examinations. The investigations were also carried out in 17 patients without CNS-SLE. The rate of detection of abnormal findings on MRI in patients with CNS-SLE was 77.2% (14/18), which was high, as compared with the rate of those on CT scans (50%: 9/18). Especially, all of 4 patients with seizure and 3 patients with encephalopathy showed abnormal MRI findings, although respectively 50% and 33.3% of them had abnormal CT scan findings. MRI findings were classified into 4 groups below: (1) Large focal are as increased signal intensity at T2 weighted image. These were observed in 2 of 4 patients with seizure and 1 of 3 patients with encephalopathy, which were completely resolved after treatment. (2) Patchy subcortical foci of increased signal intensity at T2 weighted image. These were observed in 11 of 18 CNS-SLE and 7 of 17 without CNS-SLE, which were not detected by CT scan. (3) All of six patients with cerebral infarctions showed high signal intensity areas at T2 weighted image and low signal intensity areas at T1 weighted image. (4) Normal findings were observed in 4 of 18 CNS-SLE (22.2%). We concluded that MRI is useful for the evaluation of CNS-SLE and provides more information than CT scan. (author).

  5. Abnormal findings of magnetic resonance imaging (MRI) in patients with systemic lupus erythematosus involving the brain

    International Nuclear Information System (INIS)

    Ishikawa, Akira; Okada, Jun; Kondo, Hirobumi; Kashiwazaki, Sadao.

    1992-01-01

    To elucidate the clinical significance of MRI on central nervous system systemic lupus erythematosus (CNS-SLE), MRI and CT scans were performed in 35 patients with SLE, of 18 patients who had CNS manifestations at the time of MRI examinations. The investigations were also carried out in 17 patients without CNS-SLE. The rate of detection of abnormal findings on MRI in patients with CNS-SLE was 77.2% (14/18), which was high, as compared with the rate of those on CT scans (50%: 9/18). Especially, all of 4 patients with seizure and 3 patients with encephalopathy showed abnormal MRI findings, although respectively 50% and 33.3% of them had abnormal CT scan findings. MRI findings were classified into 4 groups below: 1) Large focal are as increased signal intensity at T2 weighted image. These were observed in 2 of 4 patients with seizure and 1 of 3 patients with encephalopathy, which were completely resolved after treatment. 2) Patchy subcortical foci of increased signal intensity at T2 weighted image. These were observed in 11 of 18 CNS-SLE and 7 of 17 without CNS-SLE, which were not detected by CT scan. 3) All of six patients with cerebral infarctions showed high signal intensity areas at T2 weighted image and low signal intensity areas at T1 weighted image. 4) Normal findings were observed in 4 of 18 CNS-SLE (22.2%). We concluded that MRI is useful for the evaluation of CNS-SLE and provides more information than CT scan. (author)

  6. Scaphoid fracture: Bone marrow edema detected with dual-energy CT virtual non-calcium images and confirmed with MRI

    Energy Technology Data Exchange (ETDEWEB)

    Dareez, Nazeer M.; Engesland, Eirin; Lindland, Elisabeth S. [Department of Radiology, SSHF Arendal, Arendal (Norway); Dahlslett, Kristine H. [Haukelands Universitetssjukehus, Department of Radiology, Bergen (Norway)

    2017-12-15

    We aimed to determine whether bone marrow edema (BME) in acute traumatic scaphoid fracture could be demonstrated with dual-energy CT (DECT) using MRI as the gold standard. In recent years, virtual non-calcium (VNCa) images have been used to demonstrate BME in trauma cases, for example, in vertebral compression fractures, hip trauma to detect occult fractures and knee fractures. We present three cases of acute scaphoid trauma. Two patients had subtle or invisible fractures on x-ray and conventional CT images, while DECT VNCa images clearly visualized the BME, which was confirmed by MRI. One patient had negative findings on both VNCa and MRI images. The DECT VNCa algorithm is a promising technique to demonstrate BME in scaphoid fractures, with potential for increasing the diagnostic value of CT in this type of injury. (orig.)

  7. Brain PET and functional MRI: why simultaneously using hybrid PET/MR systems?

    Science.gov (United States)

    Cecchin, Diego; Palombit, Alessandro; Castellaro, Marco; Silvestri, Erica; Bui, Franco; Barthel, Henryk; Sabri, Osama; Corbetta, Maurizio; Bertoldo, Alessandra

    2017-12-01

    In the last 20 years growing attention has been devoted to multimodal imaging. The recent literature is rich of clinical and research studies that have been performed using different imaging modalities on both separate and integrated positron emission tomography (PET) and magnetic resonance (MR) scanners. However, today, hybrid PET/MR systems measure signals related to brain structure, metabolism, neurochemistry, perfusion, and neuronal activity simultaneously, i.e. in the same physiological conditions. A frequently raised question at meeting and symposia is: "Do we really need a hybrid PET/MR system? Are there any advantages over acquiring sequential and separate PET and MR scans?" The present paper is an attempt to answer these questions specifically in relation to PET combined with functional magnetic resonance imaging (fMRI) and arterial spin labeling. We searched (last update: June 2017) the databases PubMed, PMC, Google Scholar and Medline. We also included additional studies if they were cited in the selected articles. No language restriction was applied to the search, but the reviewed articles were all in English. Among all the retrieved articles, we selected only those performed using a hybrid PET/MR system. We found a total of 17 papers that were selected and discussed in three main groups according to the main radiopharmaceutical used: 18F-fluorodeoxyglucose (18F-FDG) (N.=8), 15O-water (15O-H2O) (N.=3) and neuroreceptors (N.=6). Concerning studies using 18F-FDG, simultaneous PET/fMRI revealed that global aspects of functional organization (e.g. graph properties of functional connections) are partially associated with energy consumption. There are remarkable spatial and functional similarities across modalities, but also discrepant findings. More work is needed on this point. There are only a handful of papers comparing blood flow measurements with PET 15O-H2O and MR arterial spin label (ASL) measures, and they show significant regional CBF differences

  8. Autonomous renewable energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    Valtchev, V. [Technical University of Varna (Bulgaria). Dept. of Electronics; Bossche, A. van den; Ghijselen, J.; Melkebeek, J. [University of Gent (Belgium). Dept. of Electrical Power Engineering

    2000-02-01

    This paper briefly reviews the need for renewable power generation and describes a medium-power Autonomous Renewable Energy Conversion System (ARECS), integrating conversion of wind and solar energy sources. The objectives of the paper are to extract maximum power from the proposed wind energy conversion scheme and to transfer this power and the power derived by the photovoltaic system in a high efficiency way to a local isolated load. The wind energy conversion operates at variable shaft speed yielding an improved annual energy production over constant speed systems. An induction generator (IG) has been used because of its reduced cost, robustness, absence of separate DC source for excitation, easier dismounting and maintenance. The maximum energy transfer of the wind energy is assured by a simple and reliable control strategy adjusting the stator frequency of the IG so that the power drawn is equal to the peak power production of the wind turbine at any wind speed. The presented control strategy also provides an optimal efficiency operation of the IG by applying a quadratic dependence between the IG terminal voltage and frequency V {approx} f{sup 2}. For improving the total system efficiency, high efficiency converters have been designed and implemented. The modular principle of the proposed DC/DC conversion provides the possibility for modifying the system structure depending on different conditions. The configuration of the presented ARECS and the implementation of the proposed control algorithm for optimal power transfer are fully discussed. The stability and dynamic performance as well as the different operation modes of the proposed control and the operation of the converters are illustrated and verified on an experimental prototype. (author)

  9. Energy Systems Integration Newsletter - December 2016 | Energy Systems

    Science.gov (United States)

    system makes renewable energy integration easier. ESIF Research Shows That Connected Residential Devices and business intelligence. Baggu also noted the opportunity to harness next-generation graphical -through, ramp rate control, soft-start reconnection, and voltage-watt control. NREL then conducted power

  10. Volume based DCE-MRI breast cancer detection with 3D visualization system

    International Nuclear Information System (INIS)

    Chia, F.K.; Sim, K.S.; Chong, S.S.; Tan, S.T.; Ting, H.Y.; Abbas, S.F.; Omar, S.

    2011-01-01

    In this paper, a computer aided design auto probing system is presented to detect breast lesions based on Dynamic contrast enhanced Magnetic resonance imaging (DCE-MRI) images. The system is proposed in order to aid the radiologists and doctors in the interpretation of MRI breast images and enhance the detection accuracy. A series of approaches are presented to enhance the detection accuracy and refine the breast region of interest (Roil) automatically. Besides, a semi-quantitative analysis is used to segment the breast lesions from selected breast Roil and classify the detected tumour is whether benign, suspicious or malignant. The entire breast Roil including the detected tumour will display in 3D. The methodology has been applied on 104 sets of digital imaging and communications in medicine (Dico) breast MRI datasets images. The biopsy results are verified by 2 radiologists from Hospital Malaysia. The experimental results are demonstrated the proposed scheme can precisely identify breast cancer regions with 93% accuracy. (author)

  11. Development of an outdoor MRI system for measuring flow in a living tree

    Science.gov (United States)

    Nagata, Akiyoshi; Kose, Katsumi; Terada, Yasuhiko

    2016-04-01

    An outdoor MRI system for noninvasive, long-term measurements of sap flow in a living tree in its natural environment has been developed. An open-access, 0.2 T permanent magnet with a 160 mm gap was combined with a radiofrequency probe, planar gradient coils, electromagnetic shielding, several electrical units, and a waterproofing box. Two-dimensional cross-sectional images were acquired for a ring-porous tree, and the anatomical structures, including xylem and phloem, were identified. The MRI flow measurements demonstrated the diurnal changes in flow velocity in the stem on a per-pixel basis. These results demonstrate that our outdoor MRI system is a powerful tool for studies of water transport in outdoor trees.

  12. MRI findings in Tolosa-Hunt syndrome before and after systemic corticosteroid therapy

    Energy Technology Data Exchange (ETDEWEB)

    Cakirer, Sinan E-mail: scakirer@yahoo.com

    2003-02-01

    Tolosa-Hunt syndrome (THS) is characterized by painful ophthalmoplegia due to a granulomatous inflammation in the cavernous sinus. Corticosteroid therapy dramatically resolves both the clinical and radiological findings of THS. We present MRI findings of six patients with a clinical history of at least one episode of unilateral or bilateral orbital-periorbital pain, clinical findings of associated paresis of one or more of 3rd, 4th, 5th or 6th cranial nerves. All of the patients revealed an enlargement of the symptomatic cavernous sinus on magnetic resonance imaging (MRI) scans. Five patients revealed total resolution of the clinical findings within 1-8 weeks, following systemic corticosteroid treatment. One patient revealed only minor regression of clinical findings within 2 weeks after the initiation of the treatment, so the cavernous sinus lesion was reevaluated as meningioma on MRI, and the patient underwent surgical resection of the mass with resultant histopathological finding of cavernous sinus meningioma. A follow-up MRI scan was performed for five patients at the end of 8-weeks of steroid therapy. Three of these five patients showed total resolution of the cavernous sinus lesions whereas two of them revealed a partial regression of the cavernous sinus lesions. MRI findings before and after systemic corticosteroid therapy are important diagnostic criteria to put the definitive diagnosis of THS and to differentiate it from other cavernous sinus lesions that simulate THS both clinically and radiologically.

  13. Energy efficient distributed computing systems

    CERN Document Server

    Lee, Young-Choon

    2012-01-01

    The energy consumption issue in distributed computing systems raises various monetary, environmental and system performance concerns. Electricity consumption in the US doubled from 2000 to 2005.  From a financial and environmental standpoint, reducing the consumption of electricity is important, yet these reforms must not lead to performance degradation of the computing systems.  These contradicting constraints create a suite of complex problems that need to be resolved in order to lead to 'greener' distributed computing systems.  This book brings together a group of outsta

  14. An optically coupled system for quantitative monitoring of MRI-induced RF currents into long conductors.

    Science.gov (United States)

    Zanchi, Marta G; Venook, Ross; Pauly, John M; Scott, Greig C

    2010-01-01

    The currents induced in long conductors such as guidewires by the radio-frequency (RF) field in magnetic resonance imaging (MRI) are responsible for potentially dangerous heating of surrounding media, such as tissue. This paper presents an optically coupled system with the potential to quantitatively measure the RF currents induced on these conductors. The system uses a self shielded toroid transducer and active circuitry to modulate a high speed light-emitting-diode transmitter. Plastic fiber guides the light to a photodiode receiver and transimpedance amplifier. System validation included a series of experiments with bare wires that compared wire tip heating by fluoroptic thermometers with the RF current sensor response. Validations were performed on a custom whole body 64 MHz birdcage test platform and on a 1.5 T MRI scanner. With this system, a variety of phenomena were demonstrated including cable trap current attenuation, lossy dielectric Q-spoiling and even transverse electromagnetic wave node patterns. This system should find applications in studies of MRI RF safety for interventional devices such as pacemaker leads, and guidewires. In particular, variations of this device could potentially act as a realtime safety monitor during MRI guided interventions.

  15. Enhanced distributed energy resource system

    Science.gov (United States)

    Atcitty, Stanley [Albuquerque, NM; Clark, Nancy H [Corrales, NM; Boyes, John D [Albuquerque, NM; Ranade, Satishkumar J [Las Cruces, NM

    2007-07-03

    A power transmission system including a direct current power source electrically connected to a conversion device for converting direct current into alternating current, a conversion device connected to a power distribution system through a junction, an energy storage device capable of producing direct current connected to a converter, where the converter, such as an insulated gate bipolar transistor, converts direct current from an energy storage device into alternating current and supplies the current to the junction and subsequently to the power distribution system. A microprocessor controller, connected to a sampling and feedback module and the converter, determines when the current load is higher than a set threshold value, requiring triggering of the converter to supply supplemental current to the power transmission system.

  16. Photovoltaic power systems energy storage

    International Nuclear Information System (INIS)

    Buldini, P.L.

    1991-01-01

    Basically, the solar photovoltaic power system consists of: Array of solar panels; Charge/voltage stabilizer; Blocking diode and Storage device. The storage device is a very important part of the system due to the necessity to harmonize the inevitable time shift between energy supply and demand. As energy storage, different devices can be utilized, such as hydropumping, air or other gas compression, flywheel, superconducting magnet, hydrogen generation and so on, but actually secondary (rechargeable) electrochemical cells appear to be the best storage device, due to the direct use for recharge of the d.c. current provided by the solar panels, without any intermediate step of energy transformation and its consequent loss of efficiency

  17. Magnetic resonance imaging (MRI) of the cardiovascular system

    International Nuclear Information System (INIS)

    Yoshida, Shigeru

    1991-01-01

    Qualitative assessments of the hypertrophied myocardium were performed using spin-lattice relaxation time (T1) and spin-spin relaxation time (T2) obtained by magnetic resonance imaging (MRI) in 15 normotensive patients with asymmetric septal hypertrophy (ASH), 10 hypertensive patients with concentric hypertrophy (CH) and 5 normal subjects (N). The changes of these values were evaluated related to cardiac cycle, and their usefulness in differentiating diseases. The wall thickness and internal dimension of the left ventricle (LV) in 10 cases were obtained using echocardiography and MRI, and there was a good correlation coefficient in wall thickness (r=0.987) and in internal dimension (r=0.991). Left ventricular short-axis images were obtained using ECG-gated spin-echo sequence (Te=30, 80 msec) and using inversion recovery sequence. T1 and T2 images were calculated at endsystolic and diastolic cardiac phases. The regional wall thickness (WT) and T1 and T2 values were measured in the anterior septum, anterior wall, lateral wall, posterior wall and posterior septum. Myocardial T1 and T2 values were significantly decreased in systole (T1: 185.6±37.9 msec, T2: 24.4±6.3 msec) compared to those in diastole (T1: 249.2±56.7 msec, T2: 31.7±9.4 msec). In both ASH and CH groups, significant correlations were observed between diastolic T1 values and WT (ASH: r=0.80, CH: r=0.45), and between diastolic T2 values and WT (ASH: r=0.58, CH: r=0.60). In the regions where diastolic WT were more than 17 mm, T1 values in the ASH group (343.4±40.5 msec) were significantly higher than those of the CH group (247.3±21.4 msec), although the mean wall thickness values were similar in both groups. These results indicate that myocardial relaxation times are related to cardiac cycle, wall thickness and types of hypertrophy. The T1 and T2 values at diastolic cardiac phase might be useful for distinguishing hypertrophic cardiomyopathy from hypertrophy due to hypertension. (author)

  18. Black blood MRI in suspected large artery primary angiitis of the central nervous system.

    Science.gov (United States)

    Pfefferkorn, Thomas; Linn, Jennifer; Habs, Maximilian; Opherk, Christina; Cyran, Clemens; Ottomeyer, Caroline; Straube, Andreas; Dichgans, Martin; Nikolaou, Konstantin; Saam, Tobias

    2013-07-01

    Single case reports suggest that black blood MRI (T1-weighted fat and blood suppressed sequences with and without contrast injection; BB-MRI) may visualize intracranial vessel wall contrast enhancement (CE) in primary angiitis of the central nervous system (PACNS). In this single-center observational pilot study we prospectively investigated the value of BB-MRI in the diagnosis of large artery PACNS. Patients with suspected large artery PACNS received a standardized diagnostic program including BB-MRI. Vessel wall CE was graded (grade 0-2) by two experienced readers blinded to clinical data and correlated to the final diagnosis. Four of 12 included patients received a final diagnosis of PACNS. All of them showed moderate (grade 1) to strong (grade 2) vessel wall CE at the sites of stenosis. A moderate (grade 1) vessel wall CE grade was also observed in 6 of the remaining 8 patients in whom alternative diagnoses were made: arteriosclerotic disease (n = 4), intracranial dissection (n = 1), and Moyamoya disease (n = 1). Our pilot study demonstrates that vessel wall CE is a frequent finding in PACNS and its mimics. Larger trials will be necessary to evaluate the utility of BB-MRI in the diagnostic workup of PACNS. Copyright © 2012 by the American Society of Neuroimaging.

  19. Value of MRI of the brain in patients with systemic lupus erythematosus and neurologic disturbance

    International Nuclear Information System (INIS)

    Jennings, J.E.; Sundgren, P.C.; Maly, P.; Attwood, J.; McCune, J.

    2004-01-01

    Our objective was to review the frequency and pattern of signal abnormalities seen on conventional MRI in patients with suspected neuropsychiatric systemic lupus erythematosus (NP-SLE). We reviewed 116 MRI examinations of the brain performed on 85 patients with SLE, (81 women, four men, aged 21-78 years, mean 40.6 years) presenting with neurological disturbances. MRI was normal or nearly normal in 34%. In 60% high-signal lesions were observed on T2-weighted images, frequently in the frontal and parietal subcortical white matter. Infarct-like lesions involving gray and white matter were demonstrated in 21 of cases. Areas of restricted diffusion were seen in 12 of the 67 patients who underwent diffusion-weighted imaging. Other abnormalities included loss of brain volume, hemorrhage, meningeal enhancement, and bilateral high signal in occipital white-matter. The MRI findings alone did not allow us to distinguish between thromboembolic and inflammatory events in many patients. Some patients with normal MRI improved clinically while on immunosuppressive therapy. More sensitive and/or specific imaging methods, such as spectroscopy and perfusion-weighted imaging, should be investigated in these subgroups of patients with suspected NP-SLE. (orig.)

  20. Development of a high-resolution detection module for the INSERT SPECT/MRI system

    Energy Technology Data Exchange (ETDEWEB)

    Busca, Paolo; Fiorini, Carlo; Butt, Arslan D; Occhipinti, Michele; Quaglia, Riccardo; Trigilio, Paolo [Politecnico di Milano, Dipartimento di Elettronica, Informazione e Bioingegneria, Via Golgi 40, 20133 Milano (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano (Italy); Nemeth, Gabor; Major, Peter; Bukki, Tamas; Nagy, Kalman [Mediso Medical Imaging Systems, Alsotorokvesz 14, H-1022 Budapest (Hungary); Piemonte, Claudio; Ferri, Alessandro; Gola, Alberto [Fondazione Bruno Kessler (FBK), Via Sommarive, 18, 38123 Trento (Italy); Rieger, Jan [MRI.TOOLS GmbH, Robert-Roessle-Str. 10, 13125 Berlin (Germany); Niendorf, Thoralf [MRI.TOOLS GmbH, Robert-Roessle-Str. 10, 13125 Berlin (Germany); Berlin Ultrahigh Field Facility (B.UniversityF.F.), Max-Delbrueck-Center for Molecular Medicine, Berlin (Germany)

    2014-07-29

    A new multi-modality imaging tool is under development in the framework of the INSERT (Integrated SPECT/MRI for Enhanced Stratification in Radio-chemo Therapy) project, supported by the European Community. The final goal is to develop a custom SPECT apparatus that can be used as an insert for commercially available MRI systems. INSERT is expected to offer more effective and earlier diagnosis with potentially better outcome in survival for the treatment of brain tumors, primarily glioma. Two SPECT prototypes are being developed, one dedicated to preclinical imaging (7 and 9.4 T), the second one dedicated to clinical imaging (3 T).

  1. PET/MRI of central nervous system: current status and future perspective

    International Nuclear Information System (INIS)

    Yang, Zhen Lu; Zhang, Long Jiang

    2016-01-01

    Imaging plays an increasingly important role in the early diagnosis, prognosis prediction and therapy response evaluation of central nervous system (CNS) diseases. The newly emerging hybrid positron emission tomography/magnetic resonance imaging (PET/MRI) can perform ''one-stop-shop'' evaluation, including anatomic, functional, biochemical and metabolic information, even at the molecular level, for personalised diagnoses and treatments of CNS diseases. However, there are still several problems to be resolved, such as appropriate PET detectors, attenuation correction and so on. This review will introduce the basic physical principles of PET/MRI and its potential clinical applications in the CNS. We also provide the future perspectives for this field. (orig.)

  2. Development of a high-resolution detection module for the INSERT SPECT/MRI system

    International Nuclear Information System (INIS)

    Busca, Paolo; Fiorini, Carlo; Butt, Arslan D; Occhipinti, Michele; Quaglia, Riccardo; Trigilio, Paolo; Nemeth, Gabor; Major, Peter; Bukki, Tamas; Nagy, Kalman; Piemonte, Claudio; Ferri, Alessandro; Gola, Alberto; Rieger, Jan; Niendorf, Thoralf

    2014-01-01

    A new multi-modality imaging tool is under development in the framework of the INSERT (Integrated SPECT/MRI for Enhanced Stratification in Radio-chemo Therapy) project, supported by the European Community. The final goal is to develop a custom SPECT apparatus that can be used as an insert for commercially available MRI systems. INSERT is expected to offer more effective and earlier diagnosis with potentially better outcome in survival for the treatment of brain tumors, primarily glioma. Two SPECT prototypes are being developed, one dedicated to preclinical imaging (7 and 9.4 T), the second one dedicated to clinical imaging (3 T).

  3. Energy savings potential from energy-conserving irrigation systems

    Energy Technology Data Exchange (ETDEWEB)

    Wilfert, G.L.; Patton, W.P.; Harrer, B.J.; Clark, M.A.

    1982-11-01

    This report systematically compares, within a consistent framework, the technical and economic characteristics of energy-conserving irrigation systems with those of conventional irrigation systems and to determine total energy savings. Levelized annual costs of owning and operating both energy-conserving and conventional irrigation systems have been developed and compared for all 17 states to account for the differences in energy costs and irrigation conditions in each state. Market penetration of energy-conserving systems is assessed for those systems having lower levelized annual costs than conventional systems performing the same function. Annual energy savings were computed by matching the energy savings per system with an assumed maximum market penetration of 100 percent in those markets where the levelized annual costs of energy-conserving systems are lower than the levelized annual costs of conventional systems.

  4. Hip Inflammation MRI Scoring System (HIMRISS) to predict response to hyaluronic acid injection in hip osteoarthritis

    DEFF Research Database (Denmark)

    Deseyne, Nicolas; Conrozier, Thierry; Lellouche, Henri

    2018-01-01

    OBJECTIVE: To assess predictors of response, according to hip MRI inflammatory scoring system (HIMRISS), in a sample of patients with hip osteoarthritis (OA) treated by hyaluronic acid (HA) injection. METHOD: Sixty patients with hip OA were included. Clinical outcomes were assessed at baseline...... SP=0.97, sensitivity SN=0.39, and positive and negative predictive values of 0.91 and 0.64, respectively. CONCLUSION: HIMRISS is reliable for total scores and sub-domains. It permits identification of responders to HA injection in hip OA patients........64, 0.83 and 0.78. Associations between MRI features and clinical data were assessed. Logistic regression (univariate and multivariate) was used to explore associations between MRI features and response to HA injection, according to WOMAC50 response at three months. RESULTS: In total, 45.5% of patients...

  5. Skeletal age assessment in children using an open compact MRI system.

    Science.gov (United States)

    Terada, Yasuhiko; Kono, Saki; Tamada, Daiki; Uchiumi, Tomomi; Kose, Katsumi; Miyagi, Ryo; Yamabe, Eiko; Yoshioka, Hiroshi

    2013-06-01

    MRI may be a noninvasive and alternative tool for skeletal age assessment in children, although few studies have reported on this topic. In this article, skeletal age was assessed over a wide range of ages using an open, compact MRI optimized for the imaging of a child's hand and wrist, and its validity was evaluated. MR images and their three-dimensional segmentation visualized detailed skeletal features of each bone in the hand and wrist. Skeletal age was then independently scored from the MR images by two raters, according to the Tanner-Whitehouse Japan system. The skeletal age assessed by MR rating demonstrated a strong positive correlation with chronological age. The intrarater and inter-rater reproducibilities were significantly high. These results demonstrate the validity and reliability of skeletal age assessment using MRI. Copyright © 2012 Wiley Periodicals, Inc.

  6. Assessment of three different software systems in the evaluation of dynamic MRI of the breast

    International Nuclear Information System (INIS)

    Kurz, K.D.; Steinhaus, D.; Klar, V.; Cohnen, M.; Wittsack, H.J.; Saleh, A.; Moedder, U.; Blondin, D.

    2009-01-01

    Objective: The aim was to compare the diagnostic performance and handling of dynamic contrast-enhanced MRI of the breast with two commercial software solutions ('CADstream' and '3TP') and one self-developed software system ('Mammatool'). Materials and methods: Identical data sets of dynamic breast MRI from 21 patients were evaluated retrospectively with all three software systems. The exams were classified according to the BI-RADS classification. The number of lesions in the parametric mapping was compared to histology or follow-up of more than 2 years. In addition, 25 quality criteria were judged by 3 independent investigators with a score from 0 to 5. Statistical analysis was performed to document the quality ranking of the different software systems. Results: There were 9 invasive carcinomas, one pure DCIS, one papilloma, one radial scar, three histologically proven changes due to mastopathy, one adenosis and two fibroadenomas. Additionally two patients with enhancing parenchyma followed with MRI for more than 3 years and one scar after breast conserving therapy were included. All malignant lesions were classified as BI-RADS 4 or 5 using all software systems and showed significant enhancement in the parametric mapping. 'CADstream' showed the best score on subjective quality criteria. '3TP' showed the lowest number of false-positive results. 'Mammatool' produced the lowest number of benign tissues indicated with parametric overlay. Conclusion: All three software programs tested were adequate for sensitive and efficient assessment of dynamic MRI of the breast. Improvements in specificity may be achievable

  7. Assessment of three different software systems in the evaluation of dynamic MRI of the breast.

    Science.gov (United States)

    Kurz, K D; Steinhaus, D; Klar, V; Cohnen, M; Wittsack, H J; Saleh, A; Mödder, U; Blondin, D

    2009-02-01

    The aim was to compare the diagnostic performance and handling of dynamic contrast-enhanced MRI of the breast with two commercial software solutions ("CADstream" and "3TP") and one self-developed software system ("Mammatool"). Identical data sets of dynamic breast MRI from 21 patients were evaluated retrospectively with all three software systems. The exams were classified according to the BI-RADS classification. The number of lesions in the parametric mapping was compared to histology or follow-up of more than 2 years. In addition, 25 quality criteria were judged by 3 independent investigators with a score from 0 to 5. Statistical analysis was performed to document the quality ranking of the different software systems. There were 9 invasive carcinomas, one pure DCIS, one papilloma, one radial scar, three histologically proven changes due to mastopathy, one adenosis and two fibroadenomas. Additionally two patients with enhancing parenchyma followed with MRI for more than 3 years and one scar after breast conserving therapy were included. All malignant lesions were classified as BI-RADS 4 or 5 using all software systems and showed significant enhancement in the parametric mapping. "CADstream" showed the best score on subjective quality criteria. "3TP" showed the lowest number of false-positive results. "Mammatool" produced the lowest number of benign tissues indicated with parametric overlay. All three software programs tested were adequate for sensitive and efficient assessment of dynamic MRI of the breast. Improvements in specificity may be achievable.

  8. Design and characterization of Stormram 4 : an MRI-compatible robotic system for breast biopsy

    NARCIS (Netherlands)

    Groenhuis, Vincent; Siepel, Françoise Jeanette; Veltman, Jeroen; Stramigioli, Stefano

    2017-01-01

    Targeting of small lesions with high precision is essential in an early phase of breast cancer for diagnosis and accurate follow up, and subsequently determines prognosis. Current techniques to diagnose breast cancer are suboptimal, and there is a need for a small, MRI-compatible robotic system able

  9. Reliability of the echoMRI infant system for water and fat measurements in newborns

    Science.gov (United States)

    The precision and accuracy of a quantitative magnetic resonance (EchoMRI Infants) system in newborns were determined. Canola oil and drinking water phantoms (increments of 10 g to 1.9 kg) were scanned four times. Instrument reproducibility was assessed from three scans (within 10 minutes) in 42 heal...

  10. Intra- and interrater reliability of three different MRI grading and classification systems after acute hamstring injuries

    International Nuclear Information System (INIS)

    Wangensteen, Arnlaug; Tol, Johannes L.; Roemer, Frank W.; Bahr, Roald; Dijkstra, H. Paul; Crema, Michel D.; Farooq, Abdulaziz; Guermazi, Ali

    2017-01-01

    Highlights: • Three different MRI grading and classification systems for acute hamstring injuries are overall reliable. • Reliability for the subcategories within these MRI grading and classification systems remains, however, unclear. - Abstract: Objective: To assess and compare the intra- and interrater reliability of three different MRI grading and classification systems after acute hamstring injury. Methods: Male athletes (n = 40) with clinical diagnosis of acute hamstring injury and MRI ≤5 days were selected from a prospective cohort. Two radiologists independently evaluated the MRIs using standardised scoring form including the modified Peetrons grading system, the Chan acute muscle strain injury classification and the British Athletics Muscle Injury Classification. Intra-and interrater reliability was assessed with linear weighted kappa (κ) or unweighted Cohen's κ and percentage agreement was calculated. Results: We observed ‘substantial’ to ‘almost perfect’ intra- (κ range 0.65–1.00) and interrater reliability (κ range 0.77–1.00) with percentage agreement 83–100% and 88–100%, respectively, for severity gradings, overall anatomical sites and overall classifications for the three MRI systems. We observed substantial variability (κ range −0.05 to 1.00) for subcategories within the Chan classification and the British Athletics Muscle Injury Classification, however, the prevalence of positive scorings was low for some subcategories. Conclusions: The modified Peetrons grading system, overall Chan classification and overall British Athletics Muscle Injury Classification demonstrated ‘substantial' to ‘almost perfect' intra- and interrater reliability when scored by experienced radiologists. The intra- and interrater reliability for the anatomical subcategories within the classifications remains unclear.

  11. Intra- and interrater reliability of three different MRI grading and classification systems after acute hamstring injuries

    Energy Technology Data Exchange (ETDEWEB)

    Wangensteen, Arnlaug, E-mail: arnlaug.wangensteen@nih.no [Aspetar, Orthopaedic and Sports Medicine Hospital, Doha (Qatar); Oslo Sports Trauma Research Center, Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo (Norway); Tol, Johannes L., E-mail: johannes.tol@aspetar.com [Aspetar, Orthopaedic and Sports Medicine Hospital, Doha (Qatar); Amsterdam Center for Evidence Sports Medicine, Academic Medical Center (Netherlands); The Sports Physician Group, OLVG, Amsterdam (Netherlands); Roemer, Frank W. [Quantitative Imaging Center, Department of Radiology, Boston University School of Medicine, Boston, MA (United States); Department of Radiology, University of Erlangen-Nuremberg, Erlangen (Germany); Bahr, Roald [Aspetar, Orthopaedic and Sports Medicine Hospital, Doha (Qatar); Oslo Sports Trauma Research Center, Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo (Norway); Dijkstra, H. Paul [Aspetar, Orthopaedic and Sports Medicine Hospital, Doha (Qatar); Crema, Michel D. [Quantitative Imaging Center, Department of Radiology, Boston University School of Medicine, Boston, MA (United States); Department of Radiology, Saint-Antoine Hospital, University Paris VI, Paris (France); Farooq, Abdulaziz [Aspetar, Orthopaedic and Sports Medicine Hospital, Doha (Qatar); Guermazi, Ali [Quantitative Imaging Center, Department of Radiology, Boston University School of Medicine, Boston, MA (United States)

    2017-04-15

    Highlights: • Three different MRI grading and classification systems for acute hamstring injuries are overall reliable. • Reliability for the subcategories within these MRI grading and classification systems remains, however, unclear. - Abstract: Objective: To assess and compare the intra- and interrater reliability of three different MRI grading and classification systems after acute hamstring injury. Methods: Male athletes (n = 40) with clinical diagnosis of acute hamstring injury and MRI ≤5 days were selected from a prospective cohort. Two radiologists independently evaluated the MRIs using standardised scoring form including the modified Peetrons grading system, the Chan acute muscle strain injury classification and the British Athletics Muscle Injury Classification. Intra-and interrater reliability was assessed with linear weighted kappa (κ) or unweighted Cohen's κ and percentage agreement was calculated. Results: We observed ‘substantial’ to ‘almost perfect’ intra- (κ range 0.65–1.00) and interrater reliability (κ range 0.77–1.00) with percentage agreement 83–100% and 88–100%, respectively, for severity gradings, overall anatomical sites and overall classifications for the three MRI systems. We observed substantial variability (κ range −0.05 to 1.00) for subcategories within the Chan classification and the British Athletics Muscle Injury Classification, however, the prevalence of positive scorings was low for some subcategories. Conclusions: The modified Peetrons grading system, overall Chan classification and overall British Athletics Muscle Injury Classification demonstrated ‘substantial' to ‘almost perfect' intra- and interrater reliability when scored by experienced radiologists. The intra- and interrater reliability for the anatomical subcategories within the classifications remains unclear.

  12. Energy Systems and Population Health

    Energy Technology Data Exchange (ETDEWEB)

    Ezzati, Majid; Bailis, Rob; Kammen, Daniel M.; Holloway, Tracey; Price, Lynn; Cifuentes, Luis A.; Barnes, Brendon; Chaurey, Akanksha; Dhanapala, Kiran N.

    2004-04-12

    It is well-documented that energy and energy systems have a central role in social and economic development and human welfare at all scales, from household and community to regional and national (41). Among its various welfare effects, energy is closely linked with people s health. Some of the effects of energy on health and welfare are direct. With abundant energy, more food or more frequent meals can be prepared; food can be refrigerated, increasing the types of food items that are consumed and reducing food contamination; water pumps can provide more water and eliminate the need for water storage leading to contamination or increased exposure to disease vectors such as mosquitoes or snails; water can be disinfected by boiling or using other technologies such as radiation. Other effects of energy on public health are mediated through more proximal determinants of health and disease. Abundant energy can lead to increased irrigation, agricultural productivity, and access to food and nutrition; access to energy can also increase small-scale income generation such as processing of agricultural commodities (e.g., producing refined oil from oil seeds, roasting coffee, drying and preserving fruits and meats) and production of crafts; ability to control lighting and heating allows education or economic activities to be shielded from daily or seasonal environmental constraints such as light, temperature, rainfall, or wind; time and other economic resources spent on collecting and/or transporting fuels can be used for other household needs if access to energy is facilitated; energy availability for transportation increases access to health and education facilities and allow increased economic activity by facilitating the transportation of goods and services to and from markets; energy for telecommunication technology (radio, television, telephone, or internet) provides increased access to information useful for health, education, or economic purposes; provision of energy

  13. Decentralized Energy from Waste Systems

    Directory of Open Access Journals (Sweden)

    Blanca Antizar-Ladislao

    2010-01-01

    Full Text Available In the last five years or so, biofuels have been given notable consideration worldwide as an alternative to fossil fuels, due to their potential to reduce greenhouse gas emissions by partial replacement of oil as a transport fuel. The production of biofuels using a sustainable approach, should consider local production of biofuels, obtained from local feedstocks and adapted to the socio-economical and environmental characteristics of the particular region where they are developed. Thus, decentralized energy from waste systems will exploit local biomass to optimize their production and consumption. Waste streams such as agricultural and wood residues, municipal solid waste, vegetable oils, and algae residues can all be integrated in energy from waste systems. An integral optimization of decentralized energy from waste systems should not be based on the optimization of each single process, but the overall optimization of the whole process. This is by obtaining optimal energy and environmental benefits, as well as collateral beneficial co-products such as soil fertilizers which will result in a higher food crop production and carbon dioxide fixation which will abate climate change.

  14. Decentralized energy from waste systems

    International Nuclear Information System (INIS)

    Antizar-Ladislao, B.; Turrion-Gomez, J. L.

    2010-01-01

    In the last five years or so, biofuels have been given notable consideration worldwide as an alternative to fossil fuels, due to their potential to reduce greenhouse gas emissions by partial replacement of oil as a transport fuel. The production of biofuels using a sustainable approach, should consider local production of biofuels, obtained from local feedstocks and adapted to the socio-economical and environmental characteristics of the particular region where they are developed. Thus, decentralized energy from waste systems will exploit local biomass to optimize their production and consumption. Waste streams such as agricultural and wood residues, municipal solid waste, vegetable oils, and algae residues can all be integrated in energy from waste systems. An integral optimization of decentralized energy from waste systems should not be based on the optimization of each single process, but the overall optimization of the whole process. This is by obtaining optimal energy and environmental benefits, as well as collateral beneficial co-products such as soil fertilizers which will result in a higher food crop production and carbon dioxide fixation which will abate climate change. (author)

  15. Agent based energy management systems

    Energy Technology Data Exchange (ETDEWEB)

    Wolter, Martin

    2012-07-01

    In liberalized, regulated energy markets, the different participants - namely producers and consumers of energy, transmission and distribution system operators as well as regulatory authorities - have partly divergent and partly convergent interests. Loads, power plants and grid operators try to maximize their own benefit in this highly complex environment accepting to act detrimentally to others. Although the relationship between the participants is mostly competitive, there are some fundamental shared interests, e.g. voltage stability, a constant system frequency or efficient energy production, transmission and distribution, which are endangered e.g. by increased injection of volatile sources in low and medium voltage grids, displacement of stabilizing bulk generation and the slowly progressing extension of the electric grid. There is a global consensus, that the resulting challenges can efficiently be faced using information and communication technologies to coordinate grid utilization and operation. The basic idea is to benefit from unused reserves by participating in deployment of system services e.g. reactive power supply to keep the voltage within certain bounds. The coordination can best be done by the grid operator. All activities of that kind are summarized under the umbrella term ''Smart Grid''. To simultaneously model the behavior and interests of different types of market participants and their convergent and divergent interests, multi-agent systems are used. They offer a perfectly fitting framework for this sort of game theory and can easily be adapted to all kinds of new challenges of electricity markets. In this work, multi-agent systems are used to either cooperatively or competitively solve problems in distribution and transmission systems. Therefore, conventional algorithms have to be modified to converge into multiple local optima using only small pieces of the entire system information. It is clearly stated, that personal

  16. Development of contaminant detection system based on ultra-low field SQUID-NMR/MRI

    International Nuclear Information System (INIS)

    Tsunaki, S; Yamamoto, M; Hatta, J; Hatsukade, Y; Tanaka, S

    2014-01-01

    We have developed an ultra-low field (ULF) NMR/MRI system using an HTS-rf-SQUID and evaluated performance of the system as a contaminant detection system for foods and drinks. In this work, we measured 1D MRIs from water samples with or without various contaminants, such as aluminum and glass balls using the system. In the 1D MRIs, changes of the MRI spectra were detected, corresponding to positions of the contaminants. We measured 2D MRIs from food samples with and without a hole. In the 2D MRIs, the hole position in the sample was well visualized. These results show that the feasibility of the system to detect and localize contaminants in foods and drinks.

  17. Heart MRI

    Science.gov (United States)

    Magnetic resonance imaging - cardiac; Magnetic resonance imaging - heart; Nuclear magnetic resonance - cardiac; NMR - cardiac; MRI of the heart; Cardiomyopathy - MRI; Heart failure - MRI; Congenital heart disease - MRI

  18. Energy Efficiency in Manufacturing Systems

    CERN Document Server

    Thiede, Sebastian

    2012-01-01

    Energy consumption is of great interest to manufacturing companies. Beyond considering individual processes and machines, the perspective on process chains and factories as a whole holds major potentials for energy efficiency improvements. To exploit these potentials, dynamic interactions of different processes as well as auxiliary equipment (e.g. compressed air generation) need to be taken into account. In addition, planning and controlling manufacturing systems require  balancing technical, economic and environmental objectives. Therefore, an innovative and comprehensive methodology – with a generic energy flow-oriented manufacturing simulation environment as a core element – is developed and embedded into a step-by-step application cycle. The concept is applied in its entirety to a wide range of case studies such as aluminium die casting, weaving mills, and printed circuit board assembly in order to demonstrate the broad applicability and the benefits that can be achieved.

  19. Total energy system in the future

    International Nuclear Information System (INIS)

    Hijikata, K.

    1994-01-01

    The possibility of improving the thermal efficiency of energy systems from an exergy point of view is discussed. In total energy systems, we should employ multi-pass recycling consisting of thermal and chemical energies. The recycling system is supported by electrical energy, which is provided by a renewable energy source or by excess commercial electric power. This total energy system should be considered not only in one country, but all around the globe. (author). 6 figs., 4 tabs., 8 refs

  20. Implementation of a ferromagnetic detection system in a clinical MRI setting

    International Nuclear Information System (INIS)

    Orchard, L.J.

    2015-01-01

    Purpose: To evaluate the implementation of a ferromagnetic detection system (FMDS) into a clinical MRI setting. Materials and methods: One thousand patients were considered for MRI safety screening using an FMDS. Equipment used was a Ferroguard ® Screener (Metrasens Ltd, Malvern, Worcestershire, UK). Fully gowned patients rotated 360° in front of the FMDS in a standardized manner following traditional MRI screening methods (the use of a written questionnaire (Fig. B.1) and verbal interview. Results: Final results included 1032 individual screening events performed in 977 patients. There were 922 (94%) initial passes using the FMDS; 34 (4%) failed initial screens but passed a subsequent screen; 21 (2%) failed the initial and subsequent screens. Thus, including all screening events (n = 1032), there were 956 (93%) true negatives (TN); 21 (2%) false positives (FP) and 55 (5%) true positives (TP). No false negatives (FN) were recorded. Therefore, sensitivity was 100% and specificity was 98%. Conclusion: Implementation and correct usage of an FMDS proved to increase safety within a clinical MRI environment by alerting staff to ferromagnetic items or implants not identified using traditional MRI screening methods. An FMDS should be used as an adjunct to these methods. The information in this study pertains to the specific equipment used in this investigation. - Highlights: • Ferromagnetic detection system sensitivity in this study was 100%. • Ferromagnetic detection system specificity in this study was 98%. • The additional screening procedure had little impact on throughput ie additional time taken was minimal. • Staff training, technique and compliance is important in implementing the screening procedures. • The ferromagnetic detection system identified objects that may have demonstrated projectile, heating or artefact effects

  1. MRI-guided periradicular nerve root infiltration therapy in low-field (0.23-T) MRI system using optical instrument tracking

    International Nuclear Information System (INIS)

    Sequeiros, Roberto Blanco; Ojala, Risto O.; Klemola, Rauli; Jyrkinen, Lasse; Tervonen, Osmo A.; Vaara, Teuvo J.

    2002-01-01

    The purpose of this study was to evaluate the feasibility of the MRI-guided periradicular nerve root infiltration therapy. Sixty-seven nerve root infiltrations under MRI guidance were done for 61 patients suffering from lumbosacral radicular pain. Informed consent was acquired from all patients. A 0.23-T open-MRI scanner with interventional tools (Outlook Proview, Philips Medical Systems, MR Technologies, Finland) was used. A surface coil was used in all cases. Nerve root infiltration was performed with MRI-compatible 20-G needle (Chiba type MReye, Cook, Bloomington, Ind.; or Manan type, MD Tech, Florida). The evaluation of clinical outcome was achieved with 6 months of clinical follow-up and questionnaire. The effect of nerve root infiltration to the radicular pain was graded: 1=good to excellent, i.e., no pain or not disturbing pain allowing normal physical activity at 3 months from the procedure; 2=temporary, i.e., temporary relief of pain; 3=no relief of pain; and 4=worsening of pain. As an adjunct to MRI-guided positioning of the needle the correct needle localization by the nerve root was confirmed with saline injection to nerve root channel and single-shot fast spin echo (SSFSE) imaging. The MRI guidance allowed adequate needle positioning in all but 1 case (98.5%). This failure was caused by degeneration-induced changes in anatomy. Of patients, 51.5% had good to excellent effect with regard to radicular pain from the procedure, 22.7% had temporary relief, 21.2% had no effect, and in 4.5% the pain worsened. Our results show that MRI guidance is accurate and safe in performing nerve root infiltration at lumbosacral area. The results of radicular pain relief from nerve root infiltration are comparable to CT or fluoroscopy studies on the subject. (orig.)

  2. TU-H-BRA-01: The Physics of High Power Radiofrequency Isolation in a Novel Compact Linear Accelerator Based MRI Guided Radiation Therapy System

    Energy Technology Data Exchange (ETDEWEB)

    Lamb, J; Low, D [University of California, Los Angeles, Los Angeles, CA (United States); Mutic, S [Washington University School of Medicine, Saint Louis, MO (United States); Shvartsman, S; Chmielewski, T; Fought, G; Sharma, A; Dempsey, J [ViewRay, Inc., Oakwood Village, OH (United States)

    2016-06-15

    Purpose: To develop a method for isolating the radiofrequency waves emanating from linear accelerator components from the magnetic resonance imaging (MRI) system of an integrated MRI-linac. Methods: An MRI-guided radiation therapy system has been designed that integrates a linear accelerator with simultaneous MR imaging. The radiofrequency waves created by the accelerating process would degrade MR image quality, so a method for containing the radiofrequency waves and isolating the MR imager from them was developed. The linear accelerator radiofrequency modulator was placed outside the room, so a filter was designed to eliminate the radiofrequency corresponding to the proton Larmour frequency of 14.7 MHz. Placing the radiofrequency emitting components in a typical Faraday cage would have reduced the radiofrequency emissions, but the design would be susceptible to small gaps in the shield due to the efficiency of the Faraday cage reflecting internal radiofrequency emissions. To reduce internal radiofrequency reflections, the Faraday cage was lined with carbon fiber sheets. Carbon fiber has the property of attenuating the radiofrequency energy so that the overall radiofrequency field inside the Faraday cage is reduced, decreasing any radiofrequency energy emitted from small gaps in the cage walls. Results: Within a 1.2 MHz band centered on the Larmor frequency, the radiofrequency (RF) leakage from the Faraday cage was measured to be −90 dB with no RF on, −40 dB with the RF on and no shield, returning to −90 dB with the RF on and shields in place. The radiofrequency filter attenuated the linear accelerator modulator emissions in the 14.7 MHz band by 70 dB. Conclusions: One of the major challenges in designing a compact linear accelerator based MRI-guided radiation therapy system, that of isolating the high power RF system from the MRI, has been solved. The measured radiofrequency emissions are sufficiently small to enable system integration. This research was

  3. TU-H-BRA-01: The Physics of High Power Radiofrequency Isolation in a Novel Compact Linear Accelerator Based MRI Guided Radiation Therapy System

    International Nuclear Information System (INIS)

    Lamb, J; Low, D; Mutic, S; Shvartsman, S; Chmielewski, T; Fought, G; Sharma, A; Dempsey, J

    2016-01-01

    Purpose: To develop a method for isolating the radiofrequency waves emanating from linear accelerator components from the magnetic resonance imaging (MRI) system of an integrated MRI-linac. Methods: An MRI-guided radiation therapy system has been designed that integrates a linear accelerator with simultaneous MR imaging. The radiofrequency waves created by the accelerating process would degrade MR image quality, so a method for containing the radiofrequency waves and isolating the MR imager from them was developed. The linear accelerator radiofrequency modulator was placed outside the room, so a filter was designed to eliminate the radiofrequency corresponding to the proton Larmour frequency of 14.7 MHz. Placing the radiofrequency emitting components in a typical Faraday cage would have reduced the radiofrequency emissions, but the design would be susceptible to small gaps in the shield due to the efficiency of the Faraday cage reflecting internal radiofrequency emissions. To reduce internal radiofrequency reflections, the Faraday cage was lined with carbon fiber sheets. Carbon fiber has the property of attenuating the radiofrequency energy so that the overall radiofrequency field inside the Faraday cage is reduced, decreasing any radiofrequency energy emitted from small gaps in the cage walls. Results: Within a 1.2 MHz band centered on the Larmor frequency, the radiofrequency (RF) leakage from the Faraday cage was measured to be −90 dB with no RF on, −40 dB with the RF on and no shield, returning to −90 dB with the RF on and shields in place. The radiofrequency filter attenuated the linear accelerator modulator emissions in the 14.7 MHz band by 70 dB. Conclusions: One of the major challenges in designing a compact linear accelerator based MRI-guided radiation therapy system, that of isolating the high power RF system from the MRI, has been solved. The measured radiofrequency emissions are sufficiently small to enable system integration. This research was

  4. Visualization of suspicious lesions in breast MRI based on intelligent neural systems

    Science.gov (United States)

    Twellmann, Thorsten; Lange, Oliver; Nattkemper, Tim Wilhelm; Meyer-Bäse, Anke

    2006-05-01

    Intelligent medical systems based on supervised and unsupervised artificial neural networks are applied to the automatic visualization and classification of suspicious lesions in breast MRI. These systems represent an important component of future sophisticated computer-aided diagnosis systems and enable the extraction of spatial and temporal features of dynamic MRI data stemming from patients with confirmed lesion diagnosis. By taking into account the heterogenity of the cancerous tissue, these techniques reveal the malignant, benign and normal kinetic signals and and provide a regional subclassification of pathological breast tissue. Intelligent medical systems are expected to have substantial implications in healthcare politics by contributing to the diagnosis of indeterminate breast lesions by non-invasive imaging.

  5. CT and MRI findings of cerebral ischemic lesions in the cortical and perforating arterial system

    Energy Technology Data Exchange (ETDEWEB)

    Kameyama, Masakuni; Udaka, Fukashi; Nishinaka, Kazuto; Kodama, Mitsuo; Urushidani, Makoto; Kawamura, Kazuyuki; Inoue, Haruhisa; Kageyama, Taku [Sumitomo Hospital, Osaka (Japan)

    1995-07-01

    It is clinically useful to divide the location of infarction into the cortical and perforating arterial system. Computerized tomography (CT) and magnetic resonance imaging (MRI) now make the point of infarction a simple and useful task in daily practice. The diagnostic modality has also demonstrated that risk factors and clinical manifestations are different for infarction in the cortical as opposed to the perforating system. In this paper, we present various aspects of images of cerebral ischemia according to CT and/or MRI findings. With the advance of imaging mechanics, diagnostic capability of CT or/and MRI for cerebral infarction has markedly been improved. We must consider these points on evaluating the previously reported results. In addition, we always consider the pathological background of these image-findings for the precise interpretation of their clinical significance. In some instances, dynamic study such as PET or SPECT is needed for real interpretations of CT and/or MRI images. We paid special reference to lacunar stroke and striatocapsular infarct. In addition, `branch atheromatous disease (Caplan)` was considered, in particular, for their specific clinical significances. Large striatocapsular infarcts frequently show cortical signs and symptoms such as aphasia or agnosia in spite of their subcortical localization. These facts, although have previously been known, should be re-considered for their pathoanatomical mechanism. (author).

  6. CT and MRI findings of cerebral ischemic lesions in the cortical and perforating arterial system

    International Nuclear Information System (INIS)

    Kameyama, Masakuni; Udaka, Fukashi; Nishinaka, Kazuto; Kodama, Mitsuo; Urushidani, Makoto; Kawamura, Kazuyuki; Inoue, Haruhisa; Kageyama, Taku

    1995-01-01

    It is clinically useful to divide the location of infarction into the cortical and perforating arterial system. Computerized tomography (CT) and magnetic resonance imaging (MRI) now make the point of infarction a simple and useful task in daily practice. The diagnostic modality has also demonstrated that risk factors and clinical manifestations are different for infarction in the cortical as opposed to the perforating system. In this paper, we present various aspects of images of cerebral ischemia according to CT and/or MRI findings. With the advance of imaging mechanics, diagnostic capability of CT or/and MRI for cerebral infarction has markedly been improved. We must consider these points on evaluating the previously reported results. In addition, we always consider the pathological background of these image-findings for the precise interpretation of their clinical significance. In some instances, dynamic study such as PET or SPECT is needed for real interpretations of CT and/or MRI images. We paid special reference to lacunar stroke and striatocapsular infarct. In addition, 'branch atheromatous disease (Caplan)' was considered, in particular, for their specific clinical significances. Large striatocapsular infarcts frequently show cortical signs and symptoms such as aphasia or agnosia in spite of their subcortical localization. These facts, although have previously been known, should be re-considered for their pathoanatomical mechanism. (author)

  7. Piezoelectrically Actuated Robotic System for MRI-Guided Prostate Percutaneous Therapy

    Science.gov (United States)

    Su, Hao; Shang, Weijian; Cole, Gregory; Li, Gang; Harrington, Kevin; Camilo, Alexander; Tokuda, Junichi; Tempany, Clare M.; Hata, Nobuhiko; Fischer, Gregory S.

    2014-01-01

    This paper presents a fully-actuated robotic system for percutaneous prostate therapy under continuously acquired live magnetic resonance imaging (MRI) guidance. The system is composed of modular hardware and software to support the surgical workflow of intra-operative MRI-guided surgical procedures. We present the development of a 6-degree-of-freedom (DOF) needle placement robot for transperineal prostate interventions. The robot consists of a 3-DOF needle driver module and a 3-DOF Cartesian motion module. The needle driver provides needle cannula translation and rotation (2-DOF) and stylet translation (1-DOF). A custom robot controller consisting of multiple piezoelectric motor drivers provides precision closed-loop control of piezoelectric motors and enables simultaneous robot motion and MR imaging. The developed modular robot control interface software performs image-based registration, kinematics calculation, and exchanges robot commands and coordinates between the navigation software and the robot controller with a new implementation of the open network communication protocol OpenIGTLink. Comprehensive compatibility of the robot is evaluated inside a 3-Tesla MRI scanner using standard imaging sequences and the signal-to-noise ratio (SNR) loss is limited to 15%. The image deterioration due to the present and motion of robot demonstrates unobservable image interference. Twenty-five targeted needle placements inside gelatin phantoms utilizing an 18-gauge ceramic needle demonstrated 0.87 mm root mean square (RMS) error in 3D Euclidean distance based on MRI volume segmentation of the image-guided robotic needle placement procedure. PMID:26412962

  8. Fat ViP MRI: Virtual Phantom Magnetic Resonance Imaging of water-fat systems.

    Science.gov (United States)

    Salvati, Roberto; Hitti, Eric; Bellanger, Jean-Jacques; Saint-Jalmes, Hervé; Gambarota, Giulio

    2016-06-01

    Virtual Phantom Magnetic Resonance Imaging (ViP MRI) is a method to generate reference signals on MR images, using external radiofrequency (RF) signals. The aim of this study was to assess the feasibility of ViP MRI to generate complex-data images of phantoms mimicking water-fat systems. Various numerical phantoms with a given fat fraction, T2* and field map were designed. The k-space of numerical phantoms was converted into RF signals to generate virtual phantoms. MRI experiments were performed at 4.7T using a multi-gradient-echo sequence on virtual and physical phantoms. The data acquisition of virtual and physical phantoms was simultaneous. Decomposition of the water and fat signals was performed using a complex-based water-fat separation algorithm. Overall, a good agreement was observed between the fat fraction, T2* and phase map values of the virtual and numerical phantoms. In particular, fat fractions of 10.5±0.1 (vs 10% of the numerical phantom), 20.3±0.1 (vs 20%) and 30.4±0.1 (vs 30%) were obtained in virtual phantoms. The ViP MRI method allows for generating imaging phantoms that i) mimic water-fat systems and ii) can be analyzed with water-fat separation algorithms based on complex data. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Visual MRI grading system to evaluate atrophy of the supeaspinatus muscle

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Hyun Kyoung; Hong, Sung Hwan; Yoo, Hye Jin; Choi, Ja Young; Kim, Sae Hoon; Choi, Jung Ah; Kang, Heung Sik [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2014-08-15

    To investigate the interobserver reproducibility and diagnostic feasibility of a visual grading system for assessing atrophy of the supraspinatus muscle on magnetic resonance imaging (MRI). Three independent radiologists retrospectively evaluated the occupying ratio of the supraspinatus muscle in the supraspinatus fossa on 192 shoulder MRI examinations in 188 patients using a 3-point visual grading system (1, ≥ 60%; 2, 30-59%; 3, < 30%) on oblique sagittal T1-weighted images. The inter-reader agreement and the agreement with the reference standard (3-point grades according to absolute occupying ratio values quantitatively measured by directly contouring the muscles on MRI) were analyzed using weighted kappa. The visual grading was applied by a single reader to a group of 100 consecutive patients who had undergone rotator cuff repair to retrospectively determine the association between the visual grades at preoperative state and postsurgical occurrences of retear. The inter-reader weighted kappa value for the visual grading was 0.74 when averaged across three reader pairs (0.70-0.77 for individual reader pairs). The weighted kappa value between the visual grading and the reference standard ranged from 0.75 to 0.83. There was a significant difference in retear rates of the rotator cuff between the 3 visual grades of supraspinatus muscle atrophy on MRI in univariable analysis (p < 0.001), but not in multivariable analysis (p = 0.026). The 3-point visual grading system may be a feasible method to assess the severity of supraspinatus muscle atrophy on MRI and assist in the clinical management of patients with rotator cuff tear.

  10. Visual MRI grading system to evaluate atrophy of the supeaspinatus muscle

    International Nuclear Information System (INIS)

    Lim, Hyun Kyoung; Hong, Sung Hwan; Yoo, Hye Jin; Choi, Ja Young; Kim, Sae Hoon; Choi, Jung Ah; Kang, Heung Sik

    2014-01-01

    To investigate the interobserver reproducibility and diagnostic feasibility of a visual grading system for assessing atrophy of the supraspinatus muscle on magnetic resonance imaging (MRI). Three independent radiologists retrospectively evaluated the occupying ratio of the supraspinatus muscle in the supraspinatus fossa on 192 shoulder MRI examinations in 188 patients using a 3-point visual grading system (1, ≥ 60%; 2, 30-59%; 3, < 30%) on oblique sagittal T1-weighted images. The inter-reader agreement and the agreement with the reference standard (3-point grades according to absolute occupying ratio values quantitatively measured by directly contouring the muscles on MRI) were analyzed using weighted kappa. The visual grading was applied by a single reader to a group of 100 consecutive patients who had undergone rotator cuff repair to retrospectively determine the association between the visual grades at preoperative state and postsurgical occurrences of retear. The inter-reader weighted kappa value for the visual grading was 0.74 when averaged across three reader pairs (0.70-0.77 for individual reader pairs). The weighted kappa value between the visual grading and the reference standard ranged from 0.75 to 0.83. There was a significant difference in retear rates of the rotator cuff between the 3 visual grades of supraspinatus muscle atrophy on MRI in univariable analysis (p < 0.001), but not in multivariable analysis (p = 0.026). The 3-point visual grading system may be a feasible method to assess the severity of supraspinatus muscle atrophy on MRI and assist in the clinical management of patients with rotator cuff tear.

  11. Energy harvesting solar, wind, and ocean energy conversion systems

    CERN Document Server

    Khaligh, Alireza

    2009-01-01

    Also called energy scavenging, energy harvesting captures, stores, and uses ""clean"" energy sources by employing interfaces, storage devices, and other units. Unlike conventional electric power generation systems, renewable energy harvesting does not use fossil fuels and the generation units can be decentralized, thereby significantly reducing transmission and distribution losses. But advanced technical methods must be developed to increase the efficiency of devices in harvesting energy from environmentally friendly, ""green"" resources and converting them into electrical energy.Recognizing t

  12. Feasibility of a brain-dedicated PET-MRI system using four-layer DOI detectors integrated with an RF head coil

    International Nuclear Information System (INIS)

    Nishikido, F.; Obata, T.; Shimizu, K.; Suga, M.; Inadama, N.; Tachibana, A.; Yoshida, E.; Ito, H.; Yamaya, T.

    2014-01-01

    We are developing a PET-MRI system which consists of PET detectors integrated with the head coil of the MRI in order to realize high spatial resolution and high sensitivity in simultaneous measurements. In the PET-MRI system, the PET detectors which consist of a scintillator block, photo-detectors and front-end circuits with four-layer depth-of-interaction (DOI) encoding capability are placed close to the measured object. Therefore, the proposed system can achieve high sensitivity without degradation of spatial resolution at the edge of the field-of-view due to parallax error thanks to the four-layer DOI capability. In this paper, we fabricated a prototype system which consists of a prototype four-layer DOI-PET detector, a dummy PET detector and a prototype birdcage type head coil. Then we used the prototype system to evaluate the performance of the four-layer DOI-PET detector and the reciprocal influence between the PET detectors and MRI images. The prototype DOI-PET detector consists of six monolithic multi-pixel photon counter (MPPC) arrays (S11064-050P), a readout circuit board, two scintillator blocks and a copper shielding box. Each scintillator block consists of four layers of Lu 1.8 Gd 0.2 SiO 5 :Ce (LGSO) scintillators and reflectors are inserted between the scintillation crystals. The dummy detector has all these components except the two scintillator blocks. The head coil is dedicated to a 3.0 T MRI (MAGNETOM Verio, Siemens) and the two detectors are mounted in gaps between head coil elements. Energy resolution and crystal identification performance of the prototype four-layer DOI-PET detector were evaluated with and without MRI measurements by the gradient echo and spin echo methods. We identified crystal elements in all four layers from a 2D flood histogram and energy resolution of 15–18% was obtained for single crystal elements in simultaneous measurements. The difference between the average energy resolutions and photo-peak positions with and

  13. The Island Smart Energy System and Market

    DEFF Research Database (Denmark)

    Ma, Zheng; Billanes, Joy Dalmacio; Jørgensen, Bo Nørregaard

    2017-01-01

    developing island smart energy systems with the integration of renewable energy resources can increase the energy supply and address the global island energy issues. The island smart energy system operates either in a single-island or in multi-islands. However the island characteristics and influ...

  14. Energy Systems Group. Annual Progress Report 1984

    DEFF Research Database (Denmark)

    Grohnheit, Poul Erik; Larsen, Hans Hvidtfeldt; Villadsen, B.

    The report describes the work of the Energy Systems Group at Risø National Laboratory during 1984. The activities may be roughly classified as development and use of energy-economy models, energy systems analysis, energy technology assessment and energy planning. The report includes a list of staff...

  15. Energy Systems Group annual progress report 1984

    International Nuclear Information System (INIS)

    Grohnheit, P.E.; Larsen, H.; Villadsen, B.

    1985-02-01

    The report describes the work of the Energy Systems Group at Risoe National Laboratory during 1984. The activities may be roughly classified as development and use of energy-economy models, energy systems analysis, energy technology assessment and energy planning. The report includes a list of staff members. (author)

  16. Integrating renewables into energy systems

    International Nuclear Information System (INIS)

    1999-03-01

    An analysis of renewable energy schemes was undertaken via case studies in China, India, Indonesia, Kenya, South Africa, Thailand and Zimbabwe, that provided an insight into the application of best practice for overcoming market, technical and financial barriers to the establishment of the sustainable markets required for the large-scale deployment of renewable energy technologies. The project showed clearly the need to select and target interventions according to the context. Lessons were extracted against a number of themes, as well as against the various technologies analysed and simple guides to the principles of best practice were derived under the following headings:- experience of gaining access to (micro) finance; the technical and non-technical issues raised when small, typically independent, generators seek access to central electricity grid systems; how to best undertake awareness raising and dissemination activities; promoting, building and operating biogas systems; promoting, building and operating solar (photovoltaic) home systems; promoting, building and operating grid connected wind power; promoting, building and operating solar hot water systems; promoting agricultural cogeneration using crop residues. (author)

  17. A compact 3 T all HTS cryogen-free MRI system

    Science.gov (United States)

    Parkinson, B. J.; Bouloukakis, K.; Slade, R. A.

    2017-12-01

    We have designed and built a passively shielded, cryogen-free 3 T 160 mm bore bismuth strontium calcium copper oxide HTS magnet with shielded gradient coils suitable for use in small animal imaging applications. The magnet is cooled to approximately 16 K using a two-stage cryocooler and is operated at 200 A. The magnet has been passively shimmed so as to achieve ±10 parts per million (ppm) homogeneity over a 60 mm diameter imaging volume. We have demonstrated that B 0 temporal stability is fit-for-purpose despite the magnet operating in the driven mode. The system has produced good quality spin-echo and gradient echo images. This compact HTS-MRI system is emerging as a true alternative to conventional low temperature superconductor based cryogen-free MRI systems, with much more efficient cryogenics since it operates entirely from a single phase alternating current electrical supply.

  18. MRI of the spinocerebellar degeneration (multiple system atrophy, Holmes type, and Menzel-Joseph type)

    International Nuclear Information System (INIS)

    Mukai, Eiichiro; Makino, Naoki.

    1991-01-01

    We have analyzed MRI in 33 patients with several forms of spinocerebellar degeneration; 17 with multiple system atrophy, 10 with Holmes type, and 6 with Menzel-Joseph type. The MRIs were obtained using a 1.5-T GEMR System. Patients with multiple system atrophy demonstrated: atrophy of the brain stem, particularly basis pontis; decreased signal intensity of the white matter of pons; atrophy of the white matter of cerebellum; atrophy and decreased signal intensity of the putamen, particularly along their lateral and posterior portions; and atrophy of the cerebrum. Patients with Holmes type showed: atrophy of the cerebellum; atrophy of the vermis more than hemispheres; and nuclei of the cerebellum with no decreased intensity on T 2 -weighted sequences. Patients with Menzel-Joseph type demonstrated moderate atrophy of the brain stem and mild atrophy of the white matter of cerebellum. MRI is a useful diagnostic tool in the management of the spinocerebellar degeneration. (author)

  19. MRI-guided prostate focal laser ablation therapy using a mechatronic needle guidance system

    Science.gov (United States)

    Cepek, Jeremy; Lindner, Uri; Ghai, Sangeet; Davidson, Sean R. H.; Trachtenberg, John; Fenster, Aaron

    2014-03-01

    Focal therapy of localized prostate cancer is receiving increased attention due to its potential for providing effective cancer control in select patients with minimal treatment-related side effects. Magnetic resonance imaging (MRI)-guided focal laser ablation (FLA) therapy is an attractive modality for such an approach. In FLA therapy, accurate placement of laser fibers is critical to ensuring that the full target volume is ablated. In practice, error in needle placement is invariably present due to pre- to intra-procedure image registration error, needle deflection, prostate motion, and variability in interventionalist skill. In addition, some of these sources of error are difficult to control, since the available workspace and patient positions are restricted within a clinical MRI bore. In an attempt to take full advantage of the utility of intraprocedure MRI, while minimizing error in needle placement, we developed an MRI-compatible mechatronic system for guiding needles to the prostate for FLA therapy. The system has been used to place interstitial catheters for MRI-guided FLA therapy in eight subjects in an ongoing Phase I/II clinical trial. Data from these cases has provided quantification of the level of uncertainty in needle placement error. To relate needle placement error to clinical outcome, we developed a model for predicting the probability of achieving complete focal target ablation for a family of parameterized treatment plans. Results from this work have enabled the specification of evidence-based selection criteria for the maximum target size that can be confidently ablated using this technique, and quantify the benefit that may be gained with improvements in needle placement accuracy.

  20. Open-Access, Low-Magnetic-Field MRI System for Lung Research

    Science.gov (United States)

    Mair, Ross W.; Rosen, Matthew S.; Tsai, Leo L.; Walsworth, Ronald L.; Hrovat, Mirko I.; Patz, Samuel; Ruset, Iullian C.; Hersman, F. William

    2009-01-01

    An open-access magnetic resonance imaging (MRI) system is being developed for use in research on orientational/gravitational effects on lung physiology and function. The open-access geometry enables study of human subjects in diverse orientations. This system operates at a magnetic flux density, considerably smaller than the flux densities of typical other MRI systems, that can be generated by resistive electromagnet coils (instead of the more-expensive superconducting coils of the other systems). The human subject inhales air containing He-3 or Xe-129 atoms, the nuclear spins of which have been polarized by use of a laser beam to obtain a magnetic resonance that enables high-resolution gas space imaging at the low applied magnetic field. The system includes a bi-planar, constant-current, four-coil electromagnet assembly and associated electronic circuitry to apply a static magnetic field of 6.5 mT throughout the lung volume; planar coils and associated circuitry to apply a pulsed magnetic-field-gradient for each spatial dimension; a single, detachable radio-frequency coil and associated circuitry for inducing and detecting MRI signals; a table for supporting a horizontal subject; and electromagnetic shielding surrounding the electromagnet coils.

  1. Central nervous system lesions in adult T-cell leukaemia: MRI and pathology

    Energy Technology Data Exchange (ETDEWEB)

    Kitajima, M.; Korogi, Y.; Shigematsu, Y.; Liang, L.; Takahashi, M. [Department of Radiology, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Matsuoka, M. [Second Division of Internal Medicine, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Yamamoto, T. [Department of Pathology, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Jhono, M. [Department of Dermatology, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Eto, K. [The National Institute for Minamata Disease, Minamata (Japan)

    2002-07-01

    Adult T-cell leukaemia (ATL) is a T-cell lymphoid neoplasm caused by human T-cell leukaemia virus type I (HTLV-I). Radiological findings in central nervous system (CNS) involvement have not been well characterised. We reviewed the MRI of 18 patients with ATL who developed new neurological symptoms or signs, and pathology specimens from a 53-year-old woman who died of ATL. MRI findings were divided into three categories: definite, probable, and other abnormal. Definite and probable findings were defined as ATL-related. The characteristic findings were multiple parenchymal masses with or without contrast enhancement adjacent to cerebrospinal fluid (CSF) spaced and the deep grey matter of both cerebral hemispheres, plus leptomeningeal lesion. One patient had both cerebral and spinal cord lesions. Other abnormal findings in eight patients included one case of leukoencephalopathy caused by methotrexate. The histology findings consisted of clusters of tumour cells along perivascular spaces, and scattered infiltration of the parenchyma, with nests of tumour cells. Leptomeningeal infiltration by tumour spread into the parenchyma and secondary degeneration of the neuronal tracts was observed. MRI was useful for detecting CNS invasion by ATL and differentiating it from other abnormalities. The MRI findings seemed to correlate well with the histological changes. (orig.)

  2. Central nervous system lesions in adult T-cell leukaemia: MRI and pathology

    International Nuclear Information System (INIS)

    Kitajima, M.; Korogi, Y.; Shigematsu, Y.; Liang, L.; Takahashi, M.; Matsuoka, M.; Yamamoto, T.; Jhono, M.; Eto, K.

    2002-01-01

    Adult T-cell leukaemia (ATL) is a T-cell lymphoid neoplasm caused by human T-cell leukaemia virus type I (HTLV-I). Radiological findings in central nervous system (CNS) involvement have not been well characterised. We reviewed the MRI of 18 patients with ATL who developed new neurological symptoms or signs, and pathology specimens from a 53-year-old woman who died of ATL. MRI findings were divided into three categories: definite, probable, and other abnormal. Definite and probable findings were defined as ATL-related. The characteristic findings were multiple parenchymal masses with or without contrast enhancement adjacent to cerebrospinal fluid (CSF) spaced and the deep grey matter of both cerebral hemispheres, plus leptomeningeal lesion. One patient had both cerebral and spinal cord lesions. Other abnormal findings in eight patients included one case of leukoencephalopathy caused by methotrexate. The histology findings consisted of clusters of tumour cells along perivascular spaces, and scattered infiltration of the parenchyma, with nests of tumour cells. Leptomeningeal infiltration by tumour spread into the parenchyma and secondary degeneration of the neuronal tracts was observed. MRI was useful for detecting CNS invasion by ATL and differentiating it from other abnormalities. The MRI findings seemed to correlate well with the histological changes. (orig.)

  3. Integrated energy optimization with smart home energy management systems

    NARCIS (Netherlands)

    Asare-Bediako, B.; Ribeiro, P.F.; Kling, W.L.

    2012-01-01

    Optimization of energy use is a vital concept in providing solutions to many of the energy challenges in our world today. Large chemical, mechanical, pneumatic, hydraulic, and electrical systems require energy efficiency as one of the important aspects of operating systems. At the micro-scale, the

  4. Power Management for Energy Systems

    DEFF Research Database (Denmark)

    Hovgaard, Tobias Gybel

    In this thesis, we consider the control of two different industrial applications that belong at either end of the electricity grid; a power consumer in the form of a commercial refrigeration system, and wind turbines for power production. Our primary studies deal with economic model predictive...... penetration of renewable, fossil-free energy sources such as solar and wind power. To facilitate such intermittent power producers, we must not only control the production of electricity, but also the consumption, in an ecient and exible manner. By enabling the use of thermal energy storage in supermarkets...... of temperature dependent efficiencies in the refrigeration cycle. -Nonlinear economic MPC with uncertain predictions and the implementation of very simple predictors that use entirely historical data of, e.g., electricity prices and outdoor temperatures. Economic MPC for wind turbines, including -Optimal steady...

  5. Integrated solar energy system optimization

    Science.gov (United States)

    Young, S. K.

    1982-11-01

    The computer program SYSOPT, intended as a tool for optimizing the subsystem sizing, performance, and economics of integrated wind and solar energy systems, is presented. The modular structure of the methodology additionally allows simulations when the solar subsystems are combined with conventional technologies, e.g., a utility grid. Hourly energy/mass flow balances are computed for interconnection points, yielding optimized sizing and time-dependent operation of various subsystems. The program requires meteorological data, such as insolation, diurnal and seasonal variations, and wind speed at the hub height of a wind turbine, all of which can be taken from simulations like the TRNSYS program. Examples are provided for optimization of a solar-powered (wind turbine and parabolic trough-Rankine generator) desalinization plant, and a design analysis for a solar powered greenhouse.

  6. MINIPILOT SOLAR SYSTEM: DESIGN/OPERATION OF SYSTEM AND RESULTS OF NON-SOLAR TESTING AT MRI

    Science.gov (United States)

    Prior to this project, MRI had carried out work for the Environmental Protection Agency (EPA) on the conceptual design of a solar system for solid waste disposal and a follow-on project to study the feasibility of bench-scale testing of desorption of organics from soil with destr...

  7. Advanced Energy Efficient Roof System

    Energy Technology Data Exchange (ETDEWEB)

    Jane Davidson

    2008-09-30

    Energy consumption in buildings represents 40 percent of primary U.S. energy consumption, split almost equally between residential (22%) and commercial (18%) buildings.1 Space heating (31%) and cooling (12%) account for approximately 9 quadrillion Btu. Improvements in the building envelope can have a significant impact on reducing energy consumption. Thermal losses (or gains) from the roof make up 14 percent of the building component energy load. Infiltration through the building envelope, including the roof, accounts for an additional 28 percent of the heating loads and 16 percent of the cooling loads. These figures provide a strong incentive to develop and implement more energy efficient roof systems. The roof is perhaps the most challenging component of the building envelope to change for many reasons. The engineered roof truss, which has been around since 1956, is relatively low cost and is the industry standard. The roof has multiple functions. A typical wood frame home lasts a long time. Building codes vary across the country. Customer and trade acceptance of new building products and materials may impede market penetration. The energy savings of a new roof system must be balanced with other requirements such as first and life-cycle costs, durability, appearance, and ease of construction. Conventional residential roof construction utilizes closely spaced roof trusses supporting a layer of sheathing and roofing materials. Gypsum board is typically attached to the lower chord of the trusses forming the finished ceiling for the occupied space. Often in warmer climates, the HVAC system and ducts are placed in the unconditioned and otherwise unusable attic. High temperature differentials and leaky ducts result in thermal losses. Penetrations through the ceilings are notoriously difficult to seal and lead to moisture and air infiltration. These issues all contribute to greater energy use and have led builders to consider construction of a conditioned attic. The

  8. Power management for energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Gybel Hovgaard, T.

    2013-02-15

    In this thesis, we consider the control of two different industrial applications that belong at either end of the electricity grid; a power consumer in the form of a commercial refrigeration system, and wind turbines for power production. Our primary studies deal with economic model predictive control of a commercial multi-zone refrigeration system, consisting of several cooling units that share a common compressor, and is used to cool multiple areas or rooms, e.g., in supermarkets. For control of the commercial refrigeration application as well as the wind turbine application, we propose an economic optimizing model predictive controller, economic MPC. Our investigations are primarily concerned with: 1) modeling of the applications to suit the chosen control framework; 2) formulating the MPC controller laws to overcome challenges introduced by the industrial applications, and defining economic objectives that reect the real physics of the systems as well as our control objectives; 3) solving the involved, non-trivial optimization problems eciently in real-time; 4) demonstrating the feasibility and potential of the proposed methods by extensive simulation and comparison with existing control methods and evaluation of data from systems in actual operation. We demonstrate, i.a., substantial cost savings, on the order of 30 %, compared to a standard thermostat-based supermarket refrigeration system and show how our methods exhibit sophisticated demand response to real-time variations in electricity prices. Violations of the temperature ranges can be kept at a very low frequency of occurrence inspite of the presence of uncertainty. For the power output from wind turbines, ramp rates, as low a 3 % of the rated power per minute, can be effectively ensured with the use of energy storage and we show how the active use of rotor inertia as an additional energy storage can reduce the needed storage capacity by up to 30 % without reducing the power output. (Author)

  9. Intra- and interrater reliability of three different MRI grading and classification systems after acute hamstring injuries.

    Science.gov (United States)

    Wangensteen, Arnlaug; Tol, Johannes L; Roemer, Frank W; Bahr, Roald; Dijkstra, H Paul; Crema, Michel D; Farooq, Abdulaziz; Guermazi, Ali

    2017-04-01

    To assess and compare the intra- and interrater reliability of three different MRI grading and classification systems after acute hamstring injury. Male athletes (n=40) with clinical diagnosis of acute hamstring injury and MRI ≤5days were selected from a prospective cohort. Two radiologists independently evaluated the MRIs using standardised scoring form including the modified Peetrons grading system, the Chan acute muscle strain injury classification and the British Athletics Muscle Injury Classification. Intra-and interrater reliability was assessed with linear weighted kappa (κ) or unweighted Cohen's κ and percentage agreement was calculated. We observed 'substantial' to 'almost perfect' intra- (κ range 0.65-1.00) and interrater reliability (κ range 0.77-1.00) with percentage agreement 83-100% and 88-100%, respectively, for severity gradings, overall anatomical sites and overall classifications for the three MRI systems. We observed substantial variability (κ range -0.05 to 1.00) for subcategories within the Chan classification and the British Athletics Muscle Injury Classification, however, the prevalence of positive scorings was low for some subcategories. The modified Peetrons grading system, overall Chan classification and overall British Athletics Muscle Injury Classification demonstrated 'substantial' to 'almost perfect' intra- and interrater reliability when scored by experienced radiologists. The intra- and interrater reliability for the anatomical subcategories within the classifications remains unclear. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Energy and environmental evaluation of tri-generation energy systems

    International Nuclear Information System (INIS)

    Chicco, G.; Mancarella, P.

    2008-01-01

    Tri generation facilities manufactured with various technologies represent an important alternative solution for the development more efficient energy systems and low environmental impact. Are described the issues related to modelling and energy and environmental evaluation [it

  11. SPECT data acquisition and image reconstruction in a stationary small animal SPECT/MRI system

    Science.gov (United States)

    Xu, Jingyan; Chen, Si; Yu, Jianhua; Meier, Dirk; Wagenaar, Douglas J.; Patt, Bradley E.; Tsui, Benjamin M. W.

    2010-04-01

    The goal of the study was to investigate data acquisition strategies and image reconstruction methods for a stationary SPECT insert that can operate inside an MRI scanner with a 12 cm bore diameter for simultaneous SPECT/MRI imaging of small animals. The SPECT insert consists of 3 octagonal rings of 8 MR-compatible CZT detectors per ring surrounding a multi-pinhole (MPH) collimator sleeve. Each pinhole is constructed to project the field-of-view (FOV) to one CZT detector. All 24 pinholes are focused to a cylindrical FOV of 25 mm in diameter and 34 mm in length. The data acquisition strategies we evaluated were optional collimator rotations to improve tomographic sampling; and the image reconstruction methods were iterative ML-EM with and without compensation for the geometric response function (GRF) of the MPH collimator. For this purpose, we developed an analytic simulator that calculates the system matrix with the GRF models of the MPH collimator. The simulator was used to generate projection data of a digital rod phantom with pinhole aperture sizes of 1 mm and 2 mm and with different collimator rotation patterns. Iterative ML-EM reconstruction with and without GRF compensation were used to reconstruct the projection data from the central ring of 8 detectors only, and from all 24 detectors. Our results indicated that without GRF compensation and at the default design of 24 projection views, the reconstructed images had significant artifacts. Accurate GRF compensation substantially improved the reconstructed image resolution and reduced image artifacts. With accurate GRF compensation, useful reconstructed images can be obtained using 24 projection views only. This last finding potentially enables dynamic SPECT (and/or MRI) studies in small animals, one of many possible application areas of the SPECT/MRI system. Further research efforts are warranted including experimentally measuring the system matrix for improved geometrical accuracy, incorporating the co

  12. A graphics processing unit accelerated motion correction algorithm and modular system for real-time fMRI.

    Science.gov (United States)

    Scheinost, Dustin; Hampson, Michelle; Qiu, Maolin; Bhawnani, Jitendra; Constable, R Todd; Papademetris, Xenophon

    2013-07-01

    Real-time functional magnetic resonance imaging (rt-fMRI) has recently gained interest as a possible means to facilitate the learning of certain behaviors. However, rt-fMRI is limited by processing speed and available software, and continued development is needed for rt-fMRI to progress further and become feasible for clinical use. In this work, we present an open-source rt-fMRI system for biofeedback powered by a novel Graphics Processing Unit (GPU) accelerated motion correction strategy as part of the BioImage Suite project ( www.bioimagesuite.org ). Our system contributes to the development of rt-fMRI by presenting a motion correction algorithm that provides an estimate of motion with essentially no processing delay as well as a modular rt-fMRI system design. Using empirical data from rt-fMRI scans, we assessed the quality of motion correction in this new system. The present algorithm performed comparably to standard (non real-time) offline methods and outperformed other real-time methods based on zero order interpolation of motion parameters. The modular approach to the rt-fMRI system allows the system to be flexible to the experiment and feedback design, a valuable feature for many applications. We illustrate the flexibility of the system by describing several of our ongoing studies. Our hope is that continuing development of open-source rt-fMRI algorithms and software will make this new technology more accessible and adaptable, and will thereby accelerate its application in the clinical and cognitive neurosciences.

  13. Loss energy states of nonstationary quantum systems

    International Nuclear Information System (INIS)

    Dodonov, V.V.; Man'ko, V.I.

    1978-01-01

    The concept of loss energy states is introduced. The loss energy states of the quantum harmonic damping oscillator are considered in detail. The method of constructing the loss energy states for general multidimensional quadratic nonstationary quantum systems is briefly discussed

  14. Battery storage for supplementing renewable energy systems

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2009-01-18

    The battery storage for renewable energy systems section of the Renewable Energy Technology Characterizations describes structures and models to support the technical and economic status of emerging renewable energy options for electricity supply.

  15. Volumetric MRI of the limbic system: anatomic determinants

    Energy Technology Data Exchange (ETDEWEB)

    Bilir, E.; Craven, W.; Hugg, J.; Gilliam, F.; Martin, R.; Faught, E.; Kuzniecky, R. [UAB Epilepsy Center, Department of Neurology, University of Alabama at Birmingham, Birmingham, AL (United States)

    1998-03-01

    The limbic system comprises the hippocampal formation, fornix, mamillary bodies, thalamus, and other integrated structures. It is involved in complex functions including memory and emotion and in diseases such as temporal lobe epilepsy. Volume measurements of the amygdala and hippocampus have been used reliably to study patients with temporal lobe epilepsy but have not extended to other limbic structures. We performed volume measurements of hippocampus, amygdala, fornix and mamillary bodies in healthy individuals. Measurements of the amygdala, hippocampus, fornix and mamillary bodies revealed significant differences in volume between right and left sides (P < 0.001). The intraclass coefficient of variation for measurements was high for all structures except the mamillary bodies. Qualitative image assessment of the same structures revealed no asymmetries between the hemispheres. This technique can be applied to the study of disorders affecting the limbic system. (orig.) With 4 figs., 2 tabs., 23 refs.

  16. Volumetric MRI of the limbic system: anatomic determinants

    International Nuclear Information System (INIS)

    Bilir, E.; Craven, W.; Hugg, J.; Gilliam, F.; Martin, R.; Faught, E.; Kuzniecky, R.

    1998-01-01

    The limbic system comprises the hippocampal formation, fornix, mamillary bodies, thalamus, and other integrated structures. It is involved in complex functions including memory and emotion and in diseases such as temporal lobe epilepsy. Volume measurements of the amygdala and hippocampus have been used reliably to study patients with temporal lobe epilepsy but have not extended to other limbic structures. We performed volume measurements of hippocampus, amygdala, fornix and mamillary bodies in healthy individuals. Measurements of the amygdala, hippocampus, fornix and mamillary bodies revealed significant differences in volume between right and left sides (P < 0.001). The intraclass coefficient of variation for measurements was high for all structures except the mamillary bodies. Qualitative image assessment of the same structures revealed no asymmetries between the hemispheres. This technique can be applied to the study of disorders affecting the limbic system. (orig.)

  17. Functional MRI of the olfactory system in conscious dogs.

    Directory of Open Access Journals (Sweden)

    Hao Jia

    Full Text Available We depend upon the olfactory abilities of dogs for critical tasks such as detecting bombs, landmines, other hazardous chemicals and illicit substances. Hence, a mechanistic understanding of the olfactory system in dogs is of great scientific interest. Previous studies explored this aspect at the cellular and behavior levels; however, the cognitive-level neural substrates linking them have never been explored. This is critical given the fact that behavior is driven by filtered sensory representations in higher order cognitive areas rather than the raw odor maps of the olfactory bulb. Since sedated dogs cannot sniff, we investigated this using functional magnetic resonance imaging of conscious dogs. We addressed the technical challenges of head motion using a two pronged strategy of behavioral training to keep dogs' head as still as possible and a single camera optical head motion tracking system to account for residual jerky movements. We built a custom computer-controlled odorant delivery system which was synchronized with image acquisition, allowing the investigation of brain regions activated by odors. The olfactory bulb and piriform lobes were commonly activated in both awake and anesthetized dogs, while the frontal cortex was activated mainly in conscious dogs. Comparison of responses to low and high odor intensity showed differences in either the strength or spatial extent of activation in the olfactory bulb, piriform lobes, cerebellum, and frontal cortex. Our results demonstrate the viability of the proposed method for functional imaging of the olfactory system in conscious dogs. This could potentially open up a new field of research in detector dog technology.

  18. Assessment of three different software systems in the evaluation of dynamic MRI of the breast

    Energy Technology Data Exchange (ETDEWEB)

    Kurz, K.D. [Department of Radiology, Stavanger University Hospital, Postbox 8100, Stavanger (Norway)], E-mail: kurk@sus.no; Steinhaus, D. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: Daniele.Steinhaus@med.uni-duesseldorf.de; Klar, V. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: verena.klar@uni-duesseldorf.de; Cohnen, M. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: cohnen@med.uni-duesseldorf.de; Wittsack, H.J. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: wittsack@uni-duesseldorf.de; Saleh, A. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: saleh@uni-duesseldorf.de; Moedder, U. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: moedder@med.uni-duesseldorf.de; Blondin, D. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: blondin@med.uni-duesseldorf.de

    2009-02-15

    Objective: The aim was to compare the diagnostic performance and handling of dynamic contrast-enhanced MRI of the breast with two commercial software solutions ('CADstream' and '3TP') and one self-developed software system ('Mammatool'). Materials and methods: Identical data sets of dynamic breast MRI from 21 patients were evaluated retrospectively with all three software systems. The exams were classified according to the BI-RADS classification. The number of lesions in the parametric mapping was compared to histology or follow-up of more than 2 years. In addition, 25 quality criteria were judged by 3 independent investigators with a score from 0 to 5. Statistical analysis was performed to document the quality ranking of the different software systems. Results: There were 9 invasive carcinomas, one pure DCIS, one papilloma, one radial scar, three histologically proven changes due to mastopathy, one adenosis and two fibroadenomas. Additionally two patients with enhancing parenchyma followed with MRI for more than 3 years and one scar after breast conserving therapy were included. All malignant lesions were classified as BI-RADS 4 or 5 using all software systems and showed significant enhancement in the parametric mapping. 'CADstream' showed the best score on subjective quality criteria. '3TP' showed the lowest number of false-positive results. 'Mammatool' produced the lowest number of benign tissues indicated with parametric overlay. Conclusion: All three software programs tested were adequate for sensitive and efficient assessment of dynamic MRI of the breast. Improvements in specificity may be achievable.

  19. Engineered Geothermal Systems Energy Return On Energy Investment

    Energy Technology Data Exchange (ETDEWEB)

    Mansure, A J

    2012-12-10

    Energy Return On Investment (EROI) is an important figure of merit for assessing the viability of energy alternatives. Too often comparisons of energy systems use efficiency when EROI would be more appropriate. For geothermal electric power generation, EROI is determined by the electricity delivered to the consumer compared to the energy consumed to construct, operate, and decommission the facility. Critical factors in determining the EROI of Engineered Geothermal Systems (EGS) are examined in this work. These include the input energy embodied into the system. Embodied energy includes the energy contained in the materials, as well as, that consumed in each stage of manufacturing from mining the raw materials to assembling the finished system. Also critical are the system boundaries and value of the energy heat is not as valuable as electrical energy. The EROI of an EGS depends upon a number of factors that are currently unknown, for example what will be typical EGS well productivity, as well as, reservoir depth, temperature, and temperature decline rate. Thus the approach developed is to consider these factors as parameters determining EROI as a function of number of wells needed. Since the energy needed to construct a geothermal well is a function of depth, results are provided as a function of well depth. Parametric determination of EGS EROI is calculated using existing information on EGS and US Department of Energy (DOE) targets and is compared to the minimum EROI an energy production system should have to be an asset rather than a liability.

  20. The OMERACT psoriatic arthritis magnetic resonance imaging scoring system (PsAMRIS): definitions of key pathologies, suggested MRI sequences, and preliminary scoring system for PsA Hands

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; McQueen, Fiona; Wiell, Charlotte

    2009-01-01

    This article describes a preliminary OMERACT psoriatic arthritis magnetic resonance image scoring system (PsAMRIS) for evaluation of inflammatory and destructive changes in PsA hands, which was developed by the international OMERACT MRI in inflammatory arthritis group. MRI definitions of important...... pathologies in peripheral PsA and suggestions concerning appropriate MRI sequences for use in PsA hands are also provided....

  1. MRI and CT appearances in metabolic encephalopathies due to systemic diseases in adults

    International Nuclear Information System (INIS)

    Bathla, G.; Hegde, A.N.

    2013-01-01

    The term encephalopathy refers to a clinical scenario of diffuse brain dysfunction, commonly due to a systemic, metabolic, or toxic derangement. Often the clinical evaluation is unsatisfactory in this scenario and imaging plays an important role in the diagnosis, assessment of treatment response, and prognostication of the disorder. Hence, it is important for radiologists to be familiar with the imaging features of some relatively frequently acquired metabolic encephalopathies encountered in the hospital setting. This study reviews the computed tomography (CT) and magnetic resonance imaging (MRI) features of a number of metabolic encephalopathies that occur as part of systemic diseases in adults. The following conditions are covered in this review: hypoglycaemic encephalopathy, hypoxic ischaemic encephalopathy, non-ketotic hyperglycaemia, hepatic encephalopathy, uraemic encephalopathy, hyperammonaemic encephalopathy, and posterior reversible encephalopathy syndrome. MRI is the imaging method of choice in evaluating these conditions. Due to their high metabolic activity, bilateral basal ganglia changes are evident in the majority of cases. Concurrent imaging abnormalities in other parts of the central nervous system often provide useful diagnostic information about the likely underlying cause of the encephalopathy. Besides this, abnormal signal intensity and diffusion restriction patterns on MRI and MR spectroscopy features may provide important clues as to the diagnosis and guide further management. Frequently, the diagnosis is not straightforward and typical imaging features require correlation with clinical and laboratory data for accurate assessment

  2. Blockchain-Assisted Crowdsourced Energy Systems

    OpenAIRE

    Wang, Shen; Taha, Ahmad; Wang, Jianhui

    2018-01-01

    Crowdsourcing relies on people's contributions to meet product- or system-level objectives. Crowdsourcing-based methods have been implemented in various cyber-physical systems and realtime markets. This paper explores a framework for Crowdsourced Energy Systems (CES), where small-scale energy generation or energy trading is crowdsourced from distributed energy resources, electric vehicles, and shapable loads. The merits/pillars of energy crowdsourcing are discussed. Then, an operational model...

  3. Bio energy: Bio energy in the Energy System of the Future

    International Nuclear Information System (INIS)

    Finden, Per; Soerensen, Heidi; Wilhelmsen, Gunnar

    2001-01-01

    This is Chapter 7, the final chapter, of the book ''Bio energy - Environment, technique and market''. Its main sections are: (1) Factors leading to changes in the energy systems, (2) The energy systems of the future, globally, (3) The future energy system in Norway and (4) Norwegian energy policy at the crossroads

  4. A Sustainable Energy System in Latvia

    DEFF Research Database (Denmark)

    Rasmussen, Lotte Holmberg

    2002-01-01

    This paper presents some of the problems in the Latvian energy system, the Latvian economy and how a sustainable restructuring of the energy system with renewable energy, co-generation and the production of energy technology can help solve some of the problems....

  5. Energy systems Diagnosis in developing countries

    International Nuclear Information System (INIS)

    Girod, J.

    1991-01-01

    Energy systems diagnosis is necessary to allow evaluation of energy balance by administration and political authorities of a country. First, the author describes the principle stages of energetic diagnosis. Then this work is divided into three parts: First part: Energy consumption diagnosis in several districts (families, utilities, agriculture, transport, industry) Second part: Energy supplies diagnosis (energy markets). Third part: Interactions between energy consumption and energy supply. 28 figs.; 52 tabs.; 107 refs

  6. Systems approach in energy management

    International Nuclear Information System (INIS)

    Dutta-Choudhury, K.

    1993-01-01

    Several years ago when the author was working in the chemicals division of a paper company in Instrumentation and Controls, one experience had a lasting impact on his work approach which is systems approach. The maintenance manager told the author that a very important piece of boiler instrument of the power plant had broken down and delivery of the replacement needed to be expedited. The instrument was ordered over the phone in another city. The purchase order was personally delivered at the supplier's office and arrangements were made so the instrument was put on the next flight. A week later the maintenance manager indicated that the particular instrument still had not arrived in the plant and he could not run the power plant. Thus the company incurred substantial losses. Further inquiries showed that the instrument did indeed arrive at the plant stores on time. But, in the absence of any instructions thereon, the instrument was not delivered to the power plant. The sense of urgency was lost in the existing delivery process. In other words, the process or system failed. The whole process from requisitioning to delivery of ordered items was analyzed and corrective procedures were incorporated to prevent future repetitions. This brings up the subject of systems approach in engineering management in general and energy management in particular. This involves defining an objective and designing a system for an effective way of getting there

  7. SMES for wind energy systems

    Science.gov (United States)

    Paul Antony, Anish

    simulation results the utility of SMES in voltage sag mitigation for momentary interruptions. The 1MJ SMES mitigates voltage sags for a useful duration ~50 seconds. In conclusion (Chapter 7), we believe that in this dissertation, we have documented the design of SMES for both momentary and sustained interruptions in wind turbines. We have put forth some novel and relevant hypotheses, developed and performed suitable simulation studies to validate these hypotheses. By doing so, we have been able to expand our knowledge in our quest to grasp the underlying mechanisms of storage systems in wind energy integration. Although the resulting analysis has allowed us to gain valuable insight, we feel that it is only the tip of the iceberg, and that many yet unknown discoveries are to be made. We remain hopeful that the future of SMES for wind energy will only look brighter from here onward. (Abstract shortened by UMI.).

  8. A low cost fMRI-compatible tracking system using the Nintendo Wii remote.

    Science.gov (United States)

    Modroño, Cristián; Rodríguez-Hernández, Antonio F; Marcano, Francisco; Navarrete, Gorka; Burunat, Enrique; Ferrer, Marta; Monserrat, Raquel; González-Mora, José L

    2011-11-15

    It is sometimes necessary during functional magnetic resonance imaging (fMRI) experiments to capture different movements made by the subjects, e.g. to enable them to control an item or to analyze its kinematics. The aim of this work is to present an inexpensive hand tracking system suitable for use in a high field MRI environment. It works by introducing only one light-emitting diode (LED) in the magnet room, and by receiving its signal with a Nintendo Wii remote (the primary controller for the Nintendo Wii console) placed outside in the control room. Thus, it is possible to take high spatial and temporal resolution registers of a moving point that, in this case, is held by the hand. We tested it using a ball and racket virtual game inside a 3 Tesla MRI scanner to demonstrate the usefulness of the system. The results show the involvement of a number of areas (mainly occipital and frontal, but also parietal and temporal) when subjects are trying to stop an object that is approaching from a first person perspective, matching previous studies performed with related visuomotor tasks. The system presented here is easy to implement, easy to operate and does not produce important head movements or artifacts in the acquired images. Given its low cost and ready availability, the method described here is ideal for use in basic and clinical fMRI research to track one or more moving points that can correspond to limbs, fingers or any other object whose position needs to be known. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. MRI-compatible audio/visual system: impact on pediatric sedation

    International Nuclear Information System (INIS)

    Harned, R.K. II; Strain, J.D.

    2001-01-01

    Background. While sedation is necessary for much pediatric imaging, there are new alternatives that may help patients hold still without medication. Objective. We examined the effect of an audio/visual system consisting of video goggles and earphones on the need for sedation during magnetic resonance imaging (MRI). Materials and methods. All MRI examinations from May 1999 to October 1999 performed after installation of the MRVision 2000 (Resonance Technology, Inc.) were compared to the same 6-month period in 1998. Imaging and sedation protocols remained constant. Data collected included: patient age, type of examination, use of intravenous contrast enhancement, and need for sedation. The average supply charge and nursing cost per sedated patient were calculated. Results. The 955 patients from 1998 and 1,112 patients from 1999 were similar in demographics and examination distribution. There was an overall reduction in the percent of patients requiring sedation in the group using the video goggle system from 49 to 40 % (P < 0.001). There was no significant change for 0-2 years (P = 0.805), but there was a reduction from 53 to 40 % for age 3-10 years (P < 0.001) and 16 to 8 % for those older than 10 years (P < 0.001). There was a 17 % decrease in MRI room time for those patients whose examinations could be performed without sedation. Sedation costs per patient were $80 for nursing and $29 for supplies. Conclusion. The use of this video system reduced the number of children requiring sedation for MRI examination by 18 %. In addition to reducing patient risk, this can potentially reduce cost. (orig.)

  10. MRI findings in central nervous system of neurofibromatosis-II

    International Nuclear Information System (INIS)

    Chen Maoen; Huang Suiqiao; Shen Jun; Hong Guobin; Wu Zhuo; Lin Xiaofeng

    2007-01-01

    Objective: To investigate the diagnostic value of MR imaging in central nervous system involvement of neurofibromatosis II. Methods: 7 patients with surgically and pathologically proved neurofibromatosis II were included. Their MR imaging findings and clinical features were retrospectively analyzed. Results: The main findings of 7 cases of neurofibraomaosis II on MR imaging included bilateral acoustic neurilemoma, multiple neurofibroma, meningioma and schwannoma. Among the 7 patients, Tl-weighted imaging after contrast enhancement displayed additional lesions which had been ignored on un-enhanced scan. Conclusion: MR imaging has advantages in the detection of central nervous sys- tem involvement of neurofibromatosis II with regard to its ability to show the lesions well, meanwhile displaying the size, morphology and signal features clearly. (authors)

  11. Two sustainable energy system analysis models

    DEFF Research Database (Denmark)

    Lund, Henrik; Goran Krajacic, Neven Duic; da Graca Carvalho, Maria

    2005-01-01

    This paper presents a comparative study of two energy system analysis models both designed with the purpose of analysing electricity systems with a substantial share of fluctuating renewable energy....

  12. Potential of renewable energy systems in China

    DEFF Research Database (Denmark)

    Liu, Wen; Lund, Henrik; Mathiesen, Brian Vad

    2011-01-01

    Along with high-speed economic development and increasing energy consumption, the Chinese Government faces a growing pressure to maintain the balance between energy supply and demand. In 2009, China has become both the largest energy consumer and CO2 emitting country in the world. In this case...... system has demonstrated the possibility of converting into a 100% renewable energy system. This paper discusses the perspective of renewable energy in China firstly, and then analyses whether it is suitable to adopt similar methodologies applied in other countries as China approaches a renewable energy...... system. The conclusion is that China’s domestic renewable energy sources are abundant and show the possibility to cover future energy demand; the methodologies used to analyse a 100% renewable energy system are applicable in China. Therefore, proposing an analysis of a 100% renewable energy system...

  13. Microcomputer-based image processing system for CT/MRI scans II

    International Nuclear Information System (INIS)

    Kwok, J.C.K.; Yu, P.K.N.; Cheng, A.Y.S.; Ho, W.C.

    1991-01-01

    This paper reports that a microcomputer-based image processing system is used to digitize and process serial sections of CT/MRI scan and reconstruct three-dimensional images of brain structures and brain lesions. The images grabbed also serve as templates and different vital regions with different risk values are also traced out for 3D reconstruction. A knowledge-based system employing rule-based programming has been built to help identifying brain lesions and to help planning trajectory for operations. The volumes of the lesions are also automatically determined. Such system is very useful for medical skills archival, tumor size monitoring, survival and outcome forecasting, and consistent neurosurgical planning

  14. Federal Tax Incentives for Energy Storage Systems

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Katherine H [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Elgqvist, Emma M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Settle, Donald E [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2018-01-16

    Investments in renewable energy are more attractive due to the contribution of two key federal tax incentives. The investment tax credit (ITC) and the Modified Accelerated Cost Recovery System (MACRS) depreciation deduction may apply to energy storage systems such as batteries depending on who owns the battery and how the battery is used. The guidelines in this fact sheet apply to energy storage systems installed at the same time as the renewable energy system.

  15. Spiral Gradient Coil Design for Use in Cylindrical MRI Systems.

    Science.gov (United States)

    Wang, Yaohui; Xin, Xuegang; Liu, Feng; Crozier, Stuart

    2018-04-01

    In magnetic resonance imaging, the stream function based method is commonly used in the design of gradient coils. However, this method can be prone to errors associated with the discretization of continuous current density and wire connections. In this paper, we propose a novel gradient coil design scheme that works directly in the wire space, avoiding the system errors that may appear in the stream function approaches. Specifically, the gradient coil pattern is described with dedicated spiral functions adjusted to allow the coil to produce the required field gradients in the imaging area, minimal stray field, and other engineering terms. The performance of a designed spiral gradient coil was compared with its stream-function counterpart. The numerical evaluation shows that when compared with the conventional solution, the inductance and resistance was reduced by 20.9 and 10.5%, respectively. The overall coil performance (evaluated by the figure of merit (FoM)) was improved up to 26.5% for the x -gradient coil design; for the z-gradient coil design, the inductance and resistance were reduced by 15.1 and 6.7% respectively, and the FoM was increased by 17.7%. In addition, by directly controlling the wire distributions, the spiral gradient coil design was much sparser than conventional coils.

  16. MRI compatibility study of an integrated PET/RF-coil prototype system at 3 T

    Science.gov (United States)

    Akram, Md Shahadat Hossain; Obata, Takayuki; Suga, Mikio; Nishikido, Fumihiko; Yoshida, Eiji; Saito, Kazuyuki; Yamaya, Taiga

    2017-10-01

    We have been working on the development of a PET insert for existing magnetic resonance imaging (MRI) systems for simultaneous PET/MR imaging, which integrates radiofrequency (RF)-shielded PET detector modules with an RF head coil. In order to avoid interferences between the PET detector circuits and the different MRI-generated electromagnetic fields, PET detector circuits were installed inside eight Cu-shielded fiber-reinforced plastic boxes, and these eight shielded PET modules were integrated in between the eight elements of a 270-mm-diameter and 280-mm-axial-length cylindrical birdcage RF coil, which was designed to be used with a 3-T clinical MRI system. The diameter of the PET scintillators with a 12-mm axial field-of-view became 255 mm, which was very close to the imaging region. In this study, we have investigated the effects of this PET/RF-coil integrated system on the performance of MRI, which include the evaluation of static field (Bo) inhomogeneity, RF field (B1) distribution, local specific absorption rate (SAR) distribution, average SAR, and signal-to-noise ratio (SNR). For the central 170-mm-diameter and 80-mm-axial-length of a homogenous cylindrical phantom (with the total diameter of 200 mm and axial-length of 100 mm), an increase of about a maximum of 3 μT in the Bo inhomogeneity was found, both in the central and 40-mm off-centered transverse planes, and a 5 percentage point increase of B1 field inhomogeneity was observed in the central transverse plane (from 84% without PET to 79% with PET), while B1 homogeneity along the coronal plane was almost unchanged (77%) following the integration of PET with the RF head coil. The average SAR and maximum local SAR were increased by 1.21 and 1.62 times, respectively. However, the SNR study for both spin-echo and gradient-echo sequences showed a reduction of about 70% and 60%, respectively, because of the shielded PET modules. The overall results prove the feasibility of this integrated PET/RF-coil system

  17. [Utilization of polymeric micelle magnetic resonance imaging (MRI) contrast agent for theranostic system].

    Science.gov (United States)

    Shiraishi, Kouichi

    2013-01-01

    We applied a polymeric micelle carrier system for the targeting of a magnetic resonance imaging (MRI) contrast agent. Prepared polymeric micelle MRI contrast agent exhibited a long circulation characteristic in blood, and considerable amount of the contrast agent was found to accumulate in colon 26 solid tumor by the EPR effect. The signal intensities of tumor area showed 2-folds increase in T1-weighted images at 24 h after i.v. injection. To observe enhancement of the EPR effect by Cderiv pretreatment on tumor targeting, we used the contrast agent for the evaluation by means of MRI. Cderiv pretreatment significantly enhanced tumor accumulation of the contrast agent. Interestingly, very high signal intensity in tumor region was found at 24 h after the contrast agent injection in Cderiv pretreated mice. The contrast agent visualized a microenvironmental change in tumor. These results indicate that the contrast agent exhibits potential use for tumor diagnostic agent. To combine with a polymeric micelle carrier system for therapeutic agent, the usage of the combination makes a new concept of "theranostic" for a better cancer treatment.

  18. PET/MRI of central nervous system: current status and future perspective

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhen Lu; Zhang, Long Jiang [Jinling Hospital, Medical School of Nanjing University, Department of Medical Imaging, Nanjing, Jiangsu (China)

    2016-10-15

    Imaging plays an increasingly important role in the early diagnosis, prognosis prediction and therapy response evaluation of central nervous system (CNS) diseases. The newly emerging hybrid positron emission tomography/magnetic resonance imaging (PET/MRI) can perform ''one-stop-shop'' evaluation, including anatomic, functional, biochemical and metabolic information, even at the molecular level, for personalised diagnoses and treatments of CNS diseases. However, there are still several problems to be resolved, such as appropriate PET detectors, attenuation correction and so on. This review will introduce the basic physical principles of PET/MRI and its potential clinical applications in the CNS. We also provide the future perspectives for this field. (orig.)

  19. CT of the musculoskeletal system: What is left is the days of MRI?

    International Nuclear Information System (INIS)

    West, A.T.H.; Marshall, T.J.; Bearcroft, P.W.

    2009-01-01

    Magnetic resonance imaging (MRI) plays a central role in the modern imaging of musculoskeletal disorders, due to its ability to produce multiplanar images and characterise soft tissues accurately. However, computed tomography (CT) still has an important role to play, not merely as an alternative to MRI, but as being the preferred imaging investigation in some situations. This article briefly reviews the history of CT technology, the technical factors involved and a number of current applications, as well as looking at future areas where CT may be employed. The advent of ever-increasing numbers of rows of detectors has opened up more possible uses for CT technology. However, diagnostic images may be obtained from CT systems with four rows of detectors or more, and their ability to produce near isotropic voxels and therefore multiplanar reformats. (orig.)

  20. Career Directions--Renewable Energy Systems Integrator

    Science.gov (United States)

    Fleeman, Stephen R.

    2012-01-01

    Renewable energy systems are beginning to appear everywhere. Solar modules are creating "blue roofs" that convert the energy from the sun into household electricity. Solar thermal systems on roofs can generate hot water. Wind turbines catch breezes to provide even more electricity. Recommendations for saving energy, specifying systems for…

  1. An enterprise energy-information system

    Energy Technology Data Exchange (ETDEWEB)

    Swords, B.; Coyle, E. [School of Control Systems and Electrical Engineering, Dublin Institute of Technology, Kevin St., Dublin 8 (Ireland); Norton, B. [President, Dublin Institute of Technology, Aungier St., Dublin 2 (Ireland)

    2008-01-15

    This paper outlines the background, development, and assessment of a prototype enterprise energy information system (EEIS) that supports strategic energy-management by providing comprehensive energy monitoring and targeting, integrating with energy modelling software and enterprise business databases, and supporting measurement and verification (M and V). The EEIS prototype system was developed and assessed in an industrial site and a third-level education institution with colleges throughout Dublin. The industrial site provided the opportunity for the EEIS to meet the requirements of a large energy intensive site, and to integrate with energy modelling software. The higher education establishment accommodated the development of a networked energy-information system. (author)

  2. Renewable energy delivery systems and methods

    Science.gov (United States)

    Walker, Howard Andrew

    2013-12-10

    A system, method and/or apparatus for the delivery of energy at a site, at least a portion of the energy being delivered by at least one or more of a plurality of renewable energy technologies, the system and method including calculating the load required by the site for the period; calculating the amount of renewable energy for the period, including obtaining a capacity and a percentage of the period for the renewable energy to be delivered; comparing the total load to the renewable energy available; and, implementing one or both of additional and alternative renewable energy sources for delivery of energy to the site.

  3. Potential of renewable energy systems in China

    International Nuclear Information System (INIS)

    Liu, Wen; Lund, Henrik; Mathiesen, Brian Vad; Zhang, Xiliang

    2011-01-01

    Along with high-speed economic development and increasing energy consumption, the Chinese Government faces a growing pressure to maintain the balance between energy supply and demand. In 2009, China has become both the largest energy consumer and CO 2 emitting country in the world. In this case, the inappropriate energy consumption structure should be changed. As an alternative, a suitable infrastructure for the implementation of renewable energy may serve as a long-term sustainable solution. The perspective of a 100% renewable energy system has been analyzed and discussed in some countries previously. In this process, assessment of domestic renewable energy sources is the first step. Then appropriate methodologies are needed to perform energy system analyses involving the integration of more sustainable strategies. Denmark may serve as an example of how sustainable strategies can be implemented. The Danish system has demonstrated the possibility of converting into a 100% renewable energy system. This paper discusses the perspective of renewable energy in China firstly, and then analyses whether it is suitable to adopt similar methodologies applied in other countries as China approaches a renewable energy system. The conclusion is that China's domestic renewable energy sources are abundant and show the possibility to cover future energy demand; the methodologies used to analyse a 100% renewable energy system are applicable in China. Therefore, proposing an analysis of a 100% renewable energy system in China is not unreasonable. (author)

  4. Evaluation of two typical distributed energy systems

    Science.gov (United States)

    Han, Miaomiao; Tan, Xiu

    2018-03-01

    According to the two-natural gas distributed energy system driven by gas engine driven and gas turbine, in this paper, the first and second laws of thermodynamics are used to measure the distributed energy system from the two parties of “quantity” and “quality”. The calculation results show that the internal combustion engine driven distributed energy station has a higher energy efficiency, but the energy efficiency is low; the gas turbine driven distributed energy station energy efficiency is high, but the primary energy utilization rate is relatively low. When configuring the system, we should determine the applicable natural gas distributed energy system technology plan and unit configuration plan according to the actual load factors of the project and the actual factors such as the location, background and environmental requirements of the project. “quality” measure, the utilization of waste heat energy efficiency index is proposed.

  5. KneeTex: an ontology-driven system for information extraction from MRI reports.

    Science.gov (United States)

    Spasić, Irena; Zhao, Bo; Jones, Christopher B; Button, Kate

    2015-01-01

    In the realm of knee pathology, magnetic resonance imaging (MRI) has the advantage of visualising all structures within the knee joint, which makes it a valuable tool for increasing diagnostic accuracy and planning surgical treatments. Therefore, clinical narratives found in MRI reports convey valuable diagnostic information. A range of studies have proven the feasibility of natural language processing for information extraction from clinical narratives. However, no study focused specifically on MRI reports in relation to knee pathology, possibly due to the complexity of knee anatomy and a wide range of conditions that may be associated with different anatomical entities. In this paper we describe KneeTex, an information extraction system that operates in this domain. As an ontology-driven information extraction system, KneeTex makes active use of an ontology to strongly guide and constrain text analysis. We used automatic term recognition to facilitate the development of a domain-specific ontology with sufficient detail and coverage for text mining applications. In combination with the ontology, high regularity of the sublanguage used in knee MRI reports allowed us to model its processing by a set of sophisticated lexico-semantic rules with minimal syntactic analysis. The main processing steps involve named entity recognition combined with coordination, enumeration, ambiguity and co-reference resolution, followed by text segmentation. Ontology-based semantic typing is then used to drive the template filling process. We adopted an existing ontology, TRAK (Taxonomy for RehAbilitation of Knee conditions), for use within KneeTex. The original TRAK ontology expanded from 1,292 concepts, 1,720 synonyms and 518 relationship instances to 1,621 concepts, 2,550 synonyms and 560 relationship instances. This provided KneeTex with a very fine-grained lexico-semantic knowledge base, which is highly attuned to the given sublanguage. Information extraction results were evaluated

  6. Hybrid Energy System Modeling in Modelica

    Energy Technology Data Exchange (ETDEWEB)

    William R. Binder; Christiaan J. J. Paredis; Humberto E. Garcia

    2014-03-01

    In this paper, a Hybrid Energy System (HES) configuration is modeled in Modelica. Hybrid Energy Systems (HES) have as their defining characteristic the use of one or more energy inputs, combined with the potential for multiple energy outputs. Compared to traditional energy systems, HES provide additional operational flexibility so that high variability in both energy production and consumption levels can be absorbed more effectively. This is particularly important when including renewable energy sources, whose output levels are inherently variable, determined by nature. The specific HES configuration modeled in this paper include two energy inputs: a nuclear plant, and a series of wind turbines. In addition, the system produces two energy outputs: electricity and synthetic fuel. The models are verified through simulations of the individual components, and the system as a whole. The simulations are performed for a range of component sizes, operating conditions, and control schemes.

  7. Energy Management Systems to Reduce Electrical Energy Consumption

    OpenAIRE

    Oriti, Giovanna

    2015-01-01

    EXECUTIVE SUMMARY An energy management system comprises an electrical energy storage element such as a battery, renewable electrical energy sources such as solar and wind, a digital signal processing controller and a solid state power converter to interface the elements together. This hardware demonstration in the lab at the Naval Postgraduate School will focus on solid state power conversion methods to improve the reliability and efficiency of electrical energy consumption by Navy facilit...

  8. Energy Signal Tool for Decision Support in Building Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Henze, G. P.; Pavlak, G. S.; Florita, A. R.; Dodier, R. H.; Hirsch, A. I.

    2014-12-01

    A prototype energy signal tool is demonstrated for operational whole-building and system-level energy use evaluation. The purpose of the tool is to give a summary of building energy use which allows a building operator to quickly distinguish normal and abnormal energy use. Toward that end, energy use status is displayed as a traffic light, which is a visual metaphor for energy use that is either substantially different from expected (red and yellow lights) or approximately the same as expected (green light). Which light to display for a given energy end use is determined by comparing expected to actual energy use. As expected, energy use is necessarily uncertain; we cannot choose the appropriate light with certainty. Instead, the energy signal tool chooses the light by minimizing the expected cost of displaying the wrong light. The expected energy use is represented by a probability distribution. Energy use is modeled by a low-order lumped parameter model. Uncertainty in energy use is quantified by a Monte Carlo exploration of the influence of model parameters on energy use. Distributions over model parameters are updated over time via Bayes' theorem. The simulation study was devised to assess whole-building energy signal accuracy in the presence of uncertainty and faults at the submetered level, which may lead to tradeoffs at the whole-building level that are not detectable without submetering.

  9. Power electronics for renewable energy systems

    DEFF Research Database (Denmark)

    Iov, Florin; Blaabjerg, Frede

    2009-01-01

    sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. Another is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss some of the most emerging renewable energy sources......, wind energy and photovoltaics, which by means of power electronics are changing from being minor energy sources to be acting as important power sources in the energy system....

  10. A Tumor-Targeted Nanodelivery System to Improve Early MRI Detection of Cancer

    Directory of Open Access Journals (Sweden)

    Kathleen F. Pirollo

    2006-01-01

    Full Text Available The development of improvements in magnetic resonance imaging (MRI that would enhance sensitivity, leading to earlier detection of cancer and visualization of metastatic disease, is an area of intense exploration. We have devised a tumor-targeting, liposomal nanodelivery platform for use in gene medicine. This systemically administered nanocomplex has been shown to specifically and efficiently deliver both genes and oligonucleotides to primary and metastatic tumor cells, resulting in significant tumor growth inhibition and even tumor regression. Here we examine the effect on MRI of incorporating conventional MRI contrast agent Magnevist® into our anti-transferrin receptor single-chain antibody (TfRscFv liposomal complex. Both in vitro and in an in vivo orthotopic mouse model of pancreatic cancer, we show increased resolution and image intensity with the complexed Magnevist®. Using advanced microscopy techniques (scanning electron microscopy and scanning probe microscopy, we also established that the Magnevist® is in fact encapsulated by the liposome in the complex and that the complex still retains its nanodimensional size. These results demonstrate that this TfRscFv-liposome-Magnevist® nanocomplex has the potential to become a useful tool in early cancer detection.

  11. MR-guided discography using an open 1 Tesla MRI system

    International Nuclear Information System (INIS)

    Streitparth, Florian; Bucourt, M. de; Hamm, B.; Teichgraeber, U.; Hartwig, T.; Strube, P.; Putzier, M.; Schnackenburg, B.; Chopra, S.

    2011-01-01

    To evaluate the feasibility of MR-guided discography using an open 1 Tesla MRI system. 48 disc segments of 41 patients scheduled for intradiscal thermal treatment, total disc replacement or spondylodesis were examined. A 1.0-T open MRI was used for instrument guidance and imaging. After primary disc puncture under guidance of interactive PDw TSE imaging, 1-2 ml of gadolinium contrast saline mixture was injected into the disc. The occurrence of memory pain during injection was recorded. Axial and sagittal T1w TSE images with and without fat saturation were obtained. All MRI discograms were analysed by two readers, who were blinded to the clinical findings. Overall, the placement of the puncture needle in the targeted disc was accurate under real-time MR guidance. Injections were technically successful in all cases. No major complications occurred. The mean procedure time was 17 min (range 13-34 min). Image quality of contrast-enhanced MR discograms was excellent when using an optimized gadolinium contrast saline mixture of 1:600. Memory pain was detected in 16 out of 48 affected segments. MR-guided discography is accurate and safe. Multiplanar dynamic imaging facilitates the puncture of discs and provides high-quality MR discograms. (orig.)

  12. Multiple fMRI system-level baseline connectivity is disrupted in patients with consciousness alterations.

    Science.gov (United States)

    Demertzi, Athena; Gómez, Francisco; Crone, Julia Sophia; Vanhaudenhuyse, Audrey; Tshibanda, Luaba; Noirhomme, Quentin; Thonnard, Marie; Charland-Verville, Vanessa; Kirsch, Murielle; Laureys, Steven; Soddu, Andrea

    2014-03-01

    In healthy conditions, group-level fMRI resting state analyses identify ten resting state networks (RSNs) of cognitive relevance. Here, we aim to assess the ten-network model in severely brain-injured patients suffering from disorders of consciousness and to identify those networks which will be most relevant to discriminate between patients and healthy subjects. 300 fMRI volumes were obtained in 27 healthy controls and 53 patients in minimally conscious state (MCS), vegetative state/unresponsive wakefulness syndrome (VS/UWS) and coma. Independent component analysis (ICA) reduced data dimensionality. The ten networks were identified by means of a multiple template-matching procedure and were tested on neuronality properties (neuronal vs non-neuronal) in a data-driven way. Univariate analyses detected between-group differences in networks' neuronal properties and estimated voxel-wise functional connectivity in the networks, which were significantly less identifiable in patients. A nearest-neighbor "clinical" classifier was used to determine the networks with high between-group discriminative accuracy. Healthy controls were characterized by more neuronal components compared to patients in VS/UWS and in coma. Compared to healthy controls, fewer patients in MCS and VS/UWS showed components of neuronal origin for the left executive control network, default mode network (DMN), auditory, and right executive control network. The "clinical" classifier indicated the DMN and auditory network with the highest accuracy (85.3%) in discriminating patients from healthy subjects. FMRI multiple-network resting state connectivity is disrupted in severely brain-injured patients suffering from disorders of consciousness. When performing ICA, multiple-network testing and control for neuronal properties of the identified RSNs can advance fMRI system-level characterization. Automatic data-driven patient classification is the first step towards future single-subject objective diagnostics

  13. Electric vehicle energy management system

    Science.gov (United States)

    Alaoui, Chakib

    This thesis investigates and analyzes novel strategies for the optimum energy management of electric vehicles (EVs). These are aimed to maximize the useful life of the EV batteries and make the EV more practical in order to increase its acceptability to market. The first strategy concerns the right choice of the batteries for the EV according to the user's driving habits, which may vary. Tests conducted at the University of Massachusetts Lowell battery lab show that the batteries perform differently from one manufacturer to the other. The second strategy was to investigate the fast chargeability of different batteries, which leads to reduce the time needed to recharge the EV battery pack. Tests were conducted again to prove that only few battery types could be fast charged. Test data were used to design a fast battery charger that could be installed in an EV charging station. The third strategy was the design, fabrication and application of an Electric Vehicle Diagnostic and Rejuvenation System (EVDRS). This system is based on Mosfet Controlled Thyristors (MCTs). It is capable of quickly identifying any failing battery(s) within the EV pack and rejuvenating the whole battery pack without dismantling them and unloading them. A novel algorithm to rejuvenate Electric Vehicle Sealed Lead Acid Batteries is described. This rejuvenation extends the useful life of the batteries and makes the EV more competitive. The fourth strategy was to design a thermal management system for EV, which is crucial to the safe operation, and the achievement of normal/optimal performance of, electric vehicle (EV) batteries. A novel approach for EV thermal management, based on Pettier-Effect heat pumps, was designed, fabricated and tested in EV. It shows the application of this type of technology for thermal management of EVs.

  14. Studies on energy system for an energy-saving society; Sho energy gata shakai ni okeru energy system kento

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    The system to which new energy technology and energy saving technology were introduced was constructed for case studies of urban areas including core cities and the peripheral areas, and the quantitative analysis was conducted on environmental effects, etc. In the energy supply system model, the following element technologies were all considered: cogeneration system, sewage water heat, river water heat, the photovoltaic power generation, energy storage/heat storage/cold heat storage, adsorption type refrigerator, etc. Also considered were power interchange between clusters, system power buying/power selling, heat interchange or no heat interchange, etc. As a result, it was found that when constructing the energy system which synthetically takes into account thermoelectric ratios, rates of simultaneous loads, ratios of daytime/nighttime in the energy supply and demand in the urban area, the energy saving effect multiplicatively increases, and the energy system using cogeneration and unused energy such as refuse and sewage in the urban area and river water brings an energy saving effect of 32% especially in the concentrated cluster. 83 figs., 45 tabs.

  15. Models of Energy Saving Systems

    DEFF Research Database (Denmark)

    Nørgård, Jørgen Stig

    1999-01-01

    only. The need for including also the economic policy in the energy planning is illustrated with what is termed the efficiency pittfall. This points towards difficulties in imaging an integrated resource planning combined with a liberalized market. The three variable parameters, population, energy...... service level and technology are demonstrated as the main determinants of future energy consumption. In the concluding remarks, the main flaws of present energy policy and some visions of the future are discussed....

  16. Power Electronics for Renewable Energy Systems

    DEFF Research Database (Denmark)

    Choi, U. M.; Lee, K. B.; Blaabjerg, Frede

    2012-01-01

    The use of renewable energy sources are increased because of the depletion of natural resources and the increasing pollution level from energy production. The wind energy and the solar energy are most widely used among the renewable energy sources. Power electronics is needed in almost all kinds...... of renewable energy system. It controls the renewable source and interfaces with the load effectively, which can be grid-connected or van work in stand-alone mode. In this presentation, overview of wind and photovoltaic energy systems are introduced. Next, the power electronic circuits behind the most common...

  17. Energy technology sources, systems and frontier conversion

    CERN Document Server

    Ohta, Tokio

    1994-01-01

    This book provides a concise and technical overview of energy technology: the sources of energy, energy systems and frontier conversion. As well as serving as a basic reference book for professional scientists and students of energy, it is intended for scientists and policy makers in other disciplines (including practising engineers, biologists, physicists, economists and managers in energy related industries) who need an up-to-date and authoritative guide to the field of energy technology.Energy systems and their elemental technologies are introduced and evaluated from the view point

  18. Identification of wind energy systems

    NARCIS (Netherlands)

    Van der Veen, G.J.

    2013-01-01

    In the next decades wind energy is expected to secure a firm share of the total energy production capacity in many countries. To increase competitiveness of wind power with other power sources it is essential to lower the cost of wind energy. Given the design of a turbine, this objective can be

  19. Energy Use in Food System

    NARCIS (Netherlands)

    Dutilh, C.; Blonk, H.; Linnemann, A.R.

    2014-01-01

    Nature generates the raw materials for food, fuelled by energy from the sun. However, before food can be consumed, (mineral) energy is required for cultivation, transportation, preparation and conservation purposes. This paper presents and discusses the energy requirements for various categories of

  20. TU-H-BRA-05: A System Design for Integration of An Interior MRI and a Linear Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Mao, W [UT Southwestern Medical Center, Dallas, TX (United States); Henry Ford Hospital, Detroit, MI (United States); Wang, G [Rensselaer Polytechnic Instit., Troy, NY (United States)

    2016-06-15

    Purpose: MRI is a highly desirable modality to guide radiation therapy but it is difficult to combine a conventional MRI scanner directly with a linear accelerator (linac). An interior MRI (iMRI) concept has been proposed to acquire MRI images within a small field of view only covering targets and immediate surrounding tissues. The objective of this project is to design an interior MRI system to work with a linac using a magnet to provide a field around 0.2T in a cube of 20cm per side, and perform image reconstruction with a slightly inhomogeneous static magnetic fields. Methods: All the results are simulated using a commercially available software package, FARADY. In our design, a ring structure holds the iMRI system and also imbeds a linac treatment head. The ring is synchronized to the linac gantry rotation. Half of the ring is made of steel and becomes a magnetic flux return path (yoke) so that a strong magnetic field will be limited inside the iron circuit and fringe fields will be very weak. In order to increase the static magnetic field homogeneity, special steel magnet boots or tips were simulated. Three curved boots were designed based on two-dimensional curves: arc, parabola and hyperbola. Results: Different boot surfaces modify magnetic field distributions differently. With the same pair of neodymium-iron-boron (NdFeB) magnets, the magnetic induction at the centers are 0.217T, 0.201T, 0.204T, and 0.212T for flat, arc, parabola and hyperbola boots, respectively. The hyperbola boots lead to the most homogeneous results, the static magnetic field deviations are within 0.5% in a cube of 20cm, and can be further improved using shimming techniques. Conclusion: This study supports the concept of an iMRI design. Successful development of iMRI will provide crucial information for tumor delineation in radiation therapy.

  1. TU-H-BRA-05: A System Design for Integration of An Interior MRI and a Linear Accelerator

    International Nuclear Information System (INIS)

    Mao, W; Wang, G

    2016-01-01

    Purpose: MRI is a highly desirable modality to guide radiation therapy but it is difficult to combine a conventional MRI scanner directly with a linear accelerator (linac). An interior MRI (iMRI) concept has been proposed to acquire MRI images within a small field of view only covering targets and immediate surrounding tissues. The objective of this project is to design an interior MRI system to work with a linac using a magnet to provide a field around 0.2T in a cube of 20cm per side, and perform image reconstruction with a slightly inhomogeneous static magnetic fields. Methods: All the results are simulated using a commercially available software package, FARADY. In our design, a ring structure holds the iMRI system and also imbeds a linac treatment head. The ring is synchronized to the linac gantry rotation. Half of the ring is made of steel and becomes a magnetic flux return path (yoke) so that a strong magnetic field will be limited inside the iron circuit and fringe fields will be very weak. In order to increase the static magnetic field homogeneity, special steel magnet boots or tips were simulated. Three curved boots were designed based on two-dimensional curves: arc, parabola and hyperbola. Results: Different boot surfaces modify magnetic field distributions differently. With the same pair of neodymium-iron-boron (NdFeB) magnets, the magnetic induction at the centers are 0.217T, 0.201T, 0.204T, and 0.212T for flat, arc, parabola and hyperbola boots, respectively. The hyperbola boots lead to the most homogeneous results, the static magnetic field deviations are within 0.5% in a cube of 20cm, and can be further improved using shimming techniques. Conclusion: This study supports the concept of an iMRI design. Successful development of iMRI will provide crucial information for tumor delineation in radiation therapy.

  2. Integrated electrofuels and renewable energy systems

    DEFF Research Database (Denmark)

    Ridjan, Iva

    energy into chemical energy by means of electrolysers, thus connecting fluctuating renewable energy to the vast amount of fuel storage already available in today’s energy systems. The conducted research indicates that electrofuels for heavy-duty transportation are technically and economically viable...... in energy systems and could play an important role in future energy systems. The cross-sector approach in the fuel production, by redirecting the excess electricity to the transport sector, is creating the flexibility and storage buffer for fluctuating electricity. The key concern in the short term should...

  3. Energy analysis of a supermarket refrigeration system

    DEFF Research Database (Denmark)

    Jensen, Jakob Munch; Jakobsen, Arne; Rasmussen, Bjarne D.

    1999-01-01

    From 1995 to 1998, an energy test method for supermarket refrigeration systems was developed in a project financed by the Danish Energy Agency. The purpose of the energy test method is to provide the means for evaluating the energy efficiency of these systems. The test method requires measurements...... of air temperatures and energy consumption to be carried out on the selected supermarket refrigeration system. In addition to the measurements required by the method, more measurements of individual energy consumptions have been carried in the case described in this paper. The purpose of the additional...

  4. The fusion-hydrogen energy system

    International Nuclear Information System (INIS)

    Williams, L.O.

    1994-01-01

    This paper will describe the structure of the system, from energy generation and hydrogen production through distribution to the end users. It will show how stationary energy users will convert to hydrogen and will outline ancillary uses of hydrogen to aid in reducing other forms of pollution. It will show that the adoption of the fusion hydrogen energy system will facilitate the use of renewable energy such as wind and solar. The development of highly efficient fuel cells for production of electricity near the user and for transportation will be outlined. The safety of the hydrogen fusion energy system is addressed. This paper will show that the combination of fusion generation combined with hydrogen distribution will provide a system capable of virtually eliminating the negative impact on the environment from the use of energy by humanity. In addition, implementation of the energy system will provide techniques and tools that can ameliorate environmental problems unrelated to energy use. (Author)

  5. Power Systems Integration Laboratory | Energy Systems Integration Facility

    Science.gov (United States)

    | NREL Power Systems Integration Laboratory Power Systems Integration Laboratory Research in the Energy System Integration Facility's Power Systems Integration Laboratory focuses on the microgrid applications. Photo of engineers testing an inverter in the Power Systems Integration Laboratory

  6. Energy Systems in the Era of Energy Vectors A Key to Define, Analyze and Design Energy Systems Beyond Fossil Fuels

    CERN Document Server

    Orecchini, Fabio

    2012-01-01

    What lies beyond the era of fossil fuels? While most answers focus on different primary energy resources, Energy Systems in the Era of Energy Vectors provides a completely new approach. Instead of providing a traditional consumption analysis of classical primary energy resources such as oil, coal, nuclear power and gas, Energy Systems in the Era of Energy Vectors describes and assesses energy technologies, markets and future strategies, focusing on their capacity to produce, exchange, and use energy vectors. Special attention is given to the renewable energy resources available in different areas of the world and made exploitable by the integration of energy vectors in the global energy system. Clear definitions of energy vectors and energy systems are used as the basis for a complete explanation and assessment of up-to-date, available technologies for energy resources, transport and storage systems, conversion and use. The energy vectors scheme allows the potential realisation of a worldwide sustainable ener...

  7. Energy storage for power systems

    CERN Document Server

    Ter-Gazarian, Andrei

    2011-01-01

    The supply of energy from primary sources is not constant and rarely matches the pattern of demand from consumers. Electricity is also difficult to store in significant quantities. Therefore, secondary storage of energy is essential to increase generation capacity efficiency and to allow more substantial use of renewable energy sources that only provide energy intermittently. Lack of effective storage has often been cited as a major hurdle to substantial introduction of renewable energy sources into the electricity supply network.This 2nd edition, without changing the existing structure of the

  8. Energy Systems Integration News | Energy Systems Integration Facility |

    Science.gov (United States)

    NREL January 2018 Blockchain concept demonstrated Blockchain to Enable Energy Market in BlockCypher Partnership NREL is partnering with BlockCypher, a blockchain Web services provider, to demonstrate how blockchain technology can support distributed energy markets. For some, the language and

  9. Rethinking Participation in Smart Energy System Planning

    NARCIS (Netherlands)

    Lammers, Imke; Arentsen, Maarten J.

    2017-01-01

    While the technical layout of smart energy systems is well advanced, the implementation of these systems is slowed down by the current decision-making practice regarding such energy infrastructures. We call for a reorganisation of the decision-making process on local energy planning and address the

  10. The intelligent energy system for tomorrow

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Hans; Morthorst, Poul Erik; Bindslev, Henrik; Sonderberg Petersen, Leif

    2010-09-15

    In a future energy system non-fossil fuels have taken the lead, end-use technologies are highly efficient and closely interlinked to supply through intelligent energy systems. Climate change issues, security of supply and economic development need to be pursued concurrently. This calls for flexible and intelligent energy system infrastructures that effectively accommodate large amounts of fluctuating renewable energy and let the end-user interact with the supply through advanced ICT. The second important characteristic is intelligent integration of the entire transport sector. The third key area is advanced energy storage facilities in the system and the introduction of super-grids.

  11. Energy Systems Integration: A Convergence of Ideas

    Energy Technology Data Exchange (ETDEWEB)

    Kroposki, B.; Garrett, B.; MacMillan, S.; Rice, B.; Komomua, C.; O' Malley, M.; Zimmerle, D.

    2012-07-01

    Energy systems integration (ESI) enables the effective analysis, design, and control of these interactions and interdependencies along technical, economic, regulatory, and social dimensions. By focusing on the optimization of energy from all systems, across all pathways, and at all scales, we can better understand and make use of the co-benefits that result to increase reliability and performance, reduce cost, and minimize environmental impacts. This white paper discusses systems integration and the research in new control architectures that are optimized at smaller scales but can be aggregated to optimize energy systems at any scale and would allow replicable energy solutions across boundaries of existing and new energy pathways.

  12. Solar energy thermally powered electrical generating system

    Science.gov (United States)

    Owens, William R. (Inventor)

    1989-01-01

    A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

  13. Modular Energy Storage System for Alternative Energy Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Janice [Magna Electronics Inc., Auburn Hills, MI (United States); Ervin, Frank [Magna Electronics Inc., Auburn Hills, MI (United States)

    2012-05-15

    An electrical vehicle environment was established to promote research and technology development in the area of high power energy management. The project incorporates a topology that permits parallel development of an alternative energy delivery system and an energy storage system. The objective of the project is to develop technologies, specifically power electronics, energy storage electronics and controls that provide efficient and effective energy management between electrically powered devices in alternative energy vehicles plugin electric vehicles, hybrid vehicles, range extended vehicles, and hydrogen-based fuel cell vehicles. In order to meet the project objectives, the Vehicle Energy Management System (VEMS) was defined and subsystem requirements were obtained. Afterwards, power electronics, energy storage electronics and controls were designed. Finally, these subsystems were built, tested individually, and integrated into an electric vehicle system to evaluate and optimize the subsystems performance. Phase 1 of the program established the fundamental test bed to support development of an electrical environment ideal for fuel cell application and the mitigation of many shortcomings of current fuel cell technology. Phase 2, continued development from Phase 1, focusing on implementing subsystem requirements, design and construction of the energy management subsystem, and the integration of this subsystem into the surrogate electric vehicle. Phase 2 also required the development of an Alternative Energy System (AES) capable of emulating electrical characteristics of fuel cells, battery, gen set, etc. Under the scope of the project, a boost converter that couples the alternate energy delivery system to the energy storage system was developed, constructed and tested. Modeling tools were utilized during the design process to optimize both component and system design. This model driven design process enabled an iterative process to track and evaluate the impact

  14. Environmentally-adapted local energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Moe, N; Oefverholm, E [NUTEK, Stockholm (Sweden); Andersson, Owe [EKAN Gruppen (Sweden); Froste, H [Swedish Environmental Protection Agency, Stockholm (Sweden)

    1997-10-01

    Energy companies, municipalities, property companies, firms of consultants, environmental groups and individuals are examples of players working locally to shape environmentally adapted energy systems. These players have needed information making them better able to make decisions on cost-efficient, environmentally-adapted energy systems. This book answers many of the questions they have put. The volume is mainly based on Swedish handbooks produced by the Swedish National Board for Industrial and Technical Development, NUTEK, together with the Swedish Environmental Protection Agency. These handbooks have been used in conjunction with municipal energy planning, local Agenda 21 work, to provide a basis for deciding on concrete local energy systems. The contents in brief: -The book throws new light on the concept of energy efficiency; -A section on the environment compares how air-polluting emissions vary with different methods of energy production; -A section contains more than 40 ideas for measures which can be profitable, reduce energy consumption and the impact on the environment all at the same time; -The book gives concrete examples of new, alternative and environmentally-adapted local energy systems. More efficient use of energy is included as a possible change of energy system; -The greatest emphasis is laid upon alternative energy systems for heating. It may be heating in a house, block of flats, office building or school; -Finally, there are examples of environmentally-adapted local energy planning.

  15. Energy Doubler cryoloop temperature monitor system

    International Nuclear Information System (INIS)

    Pucci, G.; Howard, D.

    1981-10-01

    The Cryoloop Temperature Monitor System is a fully electronic system designed to monitor temperature at key points in the Energy Doubler cryoloop system. It is used for cryoloop diagnostics, temperature studies, and cooldown valve control

  16. Improving energy efficiency in industrial energy systems an interdisciplinary perspective on barriers, energy audits, energy management, policies, and programs

    CERN Document Server

    Thollander, Patrik

    2012-01-01

    Industrial energy efficiency is one of the most important means of reducing the threat of increased global warming. Research however states that despite the existence of numerous technical energy efficiency measures, its deployment is hindered by the existence of various barriers to energy efficiency. The complexity of increasing energy efficiency in manufacturing industry calls for an interdisciplinary approach to the issue. Improving energy efficiency in industrial energy systems applies an interdisciplinary perspective in examining energy efficiency in industrial energy systems, and discuss

  17. Integrated navigation and control software system for MRI-guided robotic prostate interventions.

    Science.gov (United States)

    Tokuda, Junichi; Fischer, Gregory S; DiMaio, Simon P; Gobbi, David G; Csoma, Csaba; Mewes, Philip W; Fichtinger, Gabor; Tempany, Clare M; Hata, Nobuhiko

    2010-01-01

    A software system to provide intuitive navigation for MRI-guided robotic transperineal prostate therapy is presented. In the system, the robot control unit, the MRI scanner, and the open-source navigation software are connected together via Ethernet to exchange commands, coordinates, and images using an open network communication protocol, OpenIGTLink. The system has six states called "workphases" that provide the necessary synchronization of all components during each stage of the clinical workflow, and the user interface guides the operator linearly through these workphases. On top of this framework, the software provides the following features for needle guidance: interactive target planning; 3D image visualization with current needle position; treatment monitoring through real-time MR images of needle trajectories in the prostate. These features are supported by calibration of robot and image coordinates by fiducial-based registration. Performance tests show that the registration error of the system was 2.6mm within the prostate volume. Registered real-time 2D images were displayed 1.97 s after the image location is specified. Copyright 2009 Elsevier Ltd. All rights reserved.

  18. Integrated navigation and control software system for MRI-guided robotic prostate interventions

    Science.gov (United States)

    Tokuda, Junichi; Fischer, Gregory S.; DiMaio, Simon P.; Gobbi, David G.; Csoma, Csaba; Mewes, Philip W.; Fichtinger, Gabor; Tempany, Clare M.; Hata, Nobuhiko

    2010-01-01

    A software system to provide intuitive navigation for MRI-guided robotic transperineal prostate therapy is presented. In the system, the robot control unit, the MRI scanner, and the open-source navigation software are connected together via Ethernet to exchange commands, coordinates, and images using an open network communication protocol, OpenIGTLink. The system has six states called “workphases” that provide the necessary synchronization of all components during each stage of the clinical workflow, and the user interface guides the operator linearly through these workphases. On top of this framework, the software provides the following features for needle guidance: interactive target planning; 3D image visualization with current needle position; treatment monitoring through real-time MR images of needle trajectories in the prostate. These features are supported by calibration of robot and image coordinates by fiducial-based registration. Performance tests show that the registration error of the system was 2.6 mm within the prostate volume. Registered real-time 2D images were displayed 1.97 s after the image location is specified. PMID:19699057

  19. Altered Right Ventricular Kinetic Energy Work Density and Viscous Energy Dissipation in Patients with Pulmonary Arterial Hypertension: A Pilot Study Using 4D Flow MRI.

    Directory of Open Access Journals (Sweden)

    Q Joyce Han

    Full Text Available Right ventricular (RV function has increasingly being recognized as an important predictor for morbidity and mortality in patients with pulmonary arterial hypertension (PAH. The increased RV after-load increase RV work in PAH. We used time-resolved 3D phase contrast MRI (4D flow MRI to derive RV kinetic energy (KE work density and energy loss in the pulmonary artery (PA to better characterize RV work in PAH patients.4D flow and standard cardiac cine images were obtained in ten functional class I/II patients with PAH and nine healthy subjects. For each individual, we calculated the RV KE work density and the amount of viscous dissipation in the PA.PAH patients had alterations in flow patterns in both the RV and the PA compared to healthy subjects. PAH subjects had significantly higher RV KE work density than healthy subjects (94.7±33.7 mJ/mL vs. 61.7±14.8 mJ/mL, p = 0.007 as well as a much greater percent PA energy loss (21.1±6.4% vs. 2.2±1.3%, p = 0.0001 throughout the cardiac cycle. RV KE work density and percent PA energy loss had mild and moderate correlations with RV ejection fraction.This study has quantified two kinetic energy metrics to assess RV function using 4D flow. RV KE work density and PA viscous energy loss not only distinguished healthy subjects from patients, but also provided distinction amongst PAH patients. These metrics hold promise as imaging markers for RV function.

  20. Altered Right Ventricular Kinetic Energy Work Density and Viscous Energy Dissipation in Patients with Pulmonary Arterial Hypertension: A Pilot Study Using 4D Flow MRI.

    Science.gov (United States)

    Han, Q Joyce; Witschey, Walter R T; Fang-Yen, Christopher M; Arkles, Jeffrey S; Barker, Alex J; Forfia, Paul R; Han, Yuchi

    2015-01-01

    Right ventricular (RV) function has increasingly being recognized as an important predictor for morbidity and mortality in patients with pulmonary arterial hypertension (PAH). The increased RV after-load increase RV work in PAH. We used time-resolved 3D phase contrast MRI (4D flow MRI) to derive RV kinetic energy (KE) work density and energy loss in the pulmonary artery (PA) to better characterize RV work in PAH patients. 4D flow and standard cardiac cine images were obtained in ten functional class I/II patients with PAH and nine healthy subjects. For each individual, we calculated the RV KE work density and the amount of viscous dissipation in the PA. PAH patients had alterations in flow patterns in both the RV and the PA compared to healthy subjects. PAH subjects had significantly higher RV KE work density than healthy subjects (94.7±33.7 mJ/mL vs. 61.7±14.8 mJ/mL, p = 0.007) as well as a much greater percent PA energy loss (21.1±6.4% vs. 2.2±1.3%, p = 0.0001) throughout the cardiac cycle. RV KE work density and percent PA energy loss had mild and moderate correlations with RV ejection fraction. This study has quantified two kinetic energy metrics to assess RV function using 4D flow. RV KE work density and PA viscous energy loss not only distinguished healthy subjects from patients, but also provided distinction amongst PAH patients. These metrics hold promise as imaging markers for RV function.

  1. Introduction to wind energy systems

    Science.gov (United States)

    Wagner, H.-J.

    2017-07-01

    This article presents the basic concepts of wind energy and deals with the physics and mechanics of operation. It describes the conversion of wind energy into rotation of turbine, and the critical parameters governing the efficiency of this conversion. After that it presents an overview of various parts and components of windmills. The connection to the electrical grid, the world status of wind energy use for electricity production, the cost situation and research and development needs are further aspects which will be considered.

  2. Energy Systems Integration News | Energy Systems Integration Facility |

    Science.gov (United States)

    distributed energy resourcessolar panels, wind turbines, microgrids, and battery storagethat use smart ) panels respond to changes in solar conditions. In addition to the design and construction of the new

  3. Energy field of thermodynamic syste'ms

    International Nuclear Information System (INIS)

    Volchenkova, R.A.

    1984-01-01

    To reveal the qualitative and quantitative rules, regulating the properties of macro- and microsystems consideration is being given to the dependence of system enthalpy on environmental conditions. It was concluded that the dependence of material system enthalpy on temperature represents the energy field, containing the energy boundaries of phase states, described by exponential functions, in which the elements are arranged monotonically in the sequence of change of interatomic bonds, correlated with their physicomechanical properties; energy boundaries of phase states at that emanate from a single point, which is a reference a single point, which a reference one for the whole material system and determining its energy state in initial position. The presented energy field of thermodynamic systems enables to consider the change of their physicomechanical properties and energy state in dynamic process, depending on environmental parameters. Energy characteristics of single-component systems (W, Re, Hf, Nb, Mo etc) are given

  4. Gadolinium-enhanced MRI in central nervous system Behcet's disease

    Energy Technology Data Exchange (ETDEWEB)

    Erdem, E. (Dept. of Radiology (Neuroradiology), Hopital de Bicetre, Paris-Sud Univ. (France)); Carlier, R. (Dept. of Radiology (Neuroradiology), Hopital de Bicetre, Paris-Sud Univ. (France)); Idir, A.B.C. (Dept. of Radiology (Neuroradiology), Hopital de Bicetre, Paris-Sud Univ. (France)); Masnou, P.O. (Dept. of Neurology, Hopital de Bicetre, Paris-Sud Univ. (France)); Moulonguet, A. (Dept. of Neurology, Hopital de Bicetre, Paris-Sud Univ. (France)); Adams, D. (Dept. of Neurology, Hopital de Bicetre, Paris-Sud Univ. (France)); Doyon, D. (Dept. of Radiology (Neuroradiology), Hopital de Bicetre, Paris-Sud Univ. (France))

    1993-02-01

    Two cases of central nervous system Behcet's disease, studied by gadolinium-enhanced MRI, are presented. In one patient, whose clinical picture was dominated by a brain stem syndrome, the gadolinium enhancement resolved with clinical improvement, although the hyperintense areas in the mesencephalon on T2-weighted images persisted. In the second, who had a pseudobulbar palsy and a mild right hemiparesis, there were many abnormal areas, but an enhancing focus in the posterior limb of the left internal capsule was probably the lesion responsible for the hemiparesis. (orig.)

  5. An energy systems engineering approach to the optimal design of energy systems in commercial buildings

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Pei; Pistikopoulos, Efstratios N. [Centre for Process Systems Engineering (CPSE), Department of Chemical Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Li, Zheng [Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China)

    2010-08-15

    Energy consumption in commercial buildings accounts for a significant proportion of worldwide energy consumption. Any increase in the energy efficiency of the energy systems for commercial buildings would lead to significant energy savings and emissions reductions. In this work, we introduce an energy systems engineering framework towards the optimal design of such energy systems with improved energy efficiency and environmental performance. The framework features a superstructure representation of the various energy technology alternatives, a mixed-integer optimization formulation of the energy systems design problem, and a multi-objective design optimization solution strategy, where economic and environmental criteria are simultaneously considered and properly traded off. A case study of a supermarket energy systems design is presented to illustrate the key steps and potential of the proposed energy systems engineering approach. (author)

  6. An energy systems engineering approach to the optimal design of energy systems in commercial buildings

    International Nuclear Information System (INIS)

    Liu Pei; Pistikopoulos, Efstratios N.; Li Zheng

    2010-01-01

    Energy consumption in commercial buildings accounts for a significant proportion of worldwide energy consumption. Any increase in the energy efficiency of the energy systems for commercial buildings would lead to significant energy savings and emissions reductions. In this work, we introduce an energy systems engineering framework towards the optimal design of such energy systems with improved energy efficiency and environmental performance. The framework features a superstructure representation of the various energy technology alternatives, a mixed-integer optimization formulation of the energy systems design problem, and a multi-objective design optimization solution strategy, where economic and environmental criteria are simultaneously considered and properly traded off. A case study of a supermarket energy systems design is presented to illustrate the key steps and potential of the proposed energy systems engineering approach.

  7. An energy systems engineering approach to the optimal design of energy systems in commercial buildings

    Energy Technology Data Exchange (ETDEWEB)

    Liu Pei [Centre for Process Systems Engineering (CPSE), Department of Chemical Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Pistikopoulos, Efstratios N., E-mail: e.pistikopoulos@imperial.ac.u [Centre for Process Systems Engineering (CPSE), Department of Chemical Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Li Zheng [Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China)

    2010-08-15

    Energy consumption in commercial buildings accounts for a significant proportion of worldwide energy consumption. Any increase in the energy efficiency of the energy systems for commercial buildings would lead to significant energy savings and emissions reductions. In this work, we introduce an energy systems engineering framework towards the optimal design of such energy systems with improved energy efficiency and environmental performance. The framework features a superstructure representation of the various energy technology alternatives, a mixed-integer optimization formulation of the energy systems design problem, and a multi-objective design optimization solution strategy, where economic and environmental criteria are simultaneously considered and properly traded off. A case study of a supermarket energy systems design is presented to illustrate the key steps and potential of the proposed energy systems engineering approach.

  8. Hydrogen based energy storage for solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Vanhanen, J.; Hagstroem, M.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

    1998-10-01

    The main technical constraint in solar energy systems which operate around the year is the lack of suitable long-term energy storage. Conventional solutions to overcome the problem of seasonal storage in PV power systems are to use oversized batteries as a seasonal energy storage, or to use a diesel back-up generator. However, affordable lead-acid batteries are not very suitable for seasonal energy storage because of a high self-discharge rate and enhanced deterioration and divergence of the single cells during prolonged periods of low state of charge in times of low irradiation. These disadvantages can be avoided by a back-up system, e.g. a diesel generator, which car supply energy to the loads and charge the battery to the full state of charge to avoid the above mentioned disadvantages. Unfortunately, diesel generators have several disadvantages, e.g. poor starting reliability, frequent need for maintenance and noise

  9. Fetal MRI

    International Nuclear Information System (INIS)

    Prayer, D.; Brugger, P.C.

    2004-01-01

    New, ultrafast sequences have made it possible to obtain MR images of the fetus without maternal sedation or immobilization of the fetus itself. While fetal MRI began as an adjunct to ultrasound, it has now been shown that MRI can provide additional information that may change prognosis, the management of pregnancy, or the treatment of the newborn child. It is of particular value in the assessment of malformations of the central nervous system. The steady development and adaptation of MR-sequences to the needs of fetal imaging has led to new indications that can support prognostic and therapeutic decisions. (orig.)

  10. Interventional MRI

    Energy Technology Data Exchange (ETDEWEB)

    Harada, Junta; Dohi, Michiko; Yoshihiro, Akiko; Mogami, Takuji; Kuwada, Tomoko; Nakata, Norio [Jikei Univ., Chiba (Japan). Kashiwa Hospital

    2000-06-01

    Open type MR system and fast sequence is now available and MRI becomes a new modality for interventional Radiology, including biopsy, drainage operation, and monitoring for minimally invasive therapy. Experimental studies of temperature monitoring were performed under hot and cold status. Signal changes of porcine disc and meat under microwave and laser ablation were observed as low signal area by signal intensity method. Using proton chemical shift method, signal change by laser ablation was displaced color imaging and correlated with thermometric temperature measurement. The very T2 relaxation time of ice affords excellent contrast between ice and surrounding gelatin tissue allowing acute depiction of the extent of the iceball under MRI. (author)

  11. Fetal MRI

    Energy Technology Data Exchange (ETDEWEB)

    Prayer, D.; Brugger, P.C. [University Hospital of Vienna (Austria). Division of Neuroradiology

    2004-07-01

    New, ultrafast sequences have made it possible to obtain MR images of the fetus without maternal sedation or immobilization of the fetus itself. While fetal MRI began as an adjunct to ultrasound, it has now been shown that MRI can provide additional information that may change prognosis, the management of pregnancy, or the treatment of the newborn child. It is of particular value in the assessment of malformations of the central nervous system. The steady development and adaptation of MR-sequences to the needs of fetal imaging has led to new indications that can support prognostic and therapeutic decisions. (orig.)

  12. Energy Prices and Internal Costs in Croatian Energy System Restructuring

    International Nuclear Information System (INIS)

    Potocnik, V. , Magdic, M.

    1995-01-01

    After social and political changes in 1990, energy prices in Croatia have been getting closer to the West European averages, faster than in the most European countries in transition. The energy prices for industry are almost at the West European level, while the energy prices of electricity and natural gas for households and those of the gasoline are well behind. If the population purchasing power parity (PPP) is taken into account, these relations change. While the internalization of external energy costs is under way in the developed world, it has not practically started yet in Croatia. The Croatian energy system restructuring shall require gradual adjustment of energy prices, together with multistage internalization of external energy costs. (author). 6 refs., 3 tabs., 2 figs

  13. Financial overview of integrated community energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Croke, K. G.; Hurter, A. P.; Lerner, E.; Breen, W.; Baum, J.

    1977-01-01

    This report is designed to analyze the commercialization potential of various concepts of community-scale energy systems that have been termed Integrated Community Energy Systems (ICES). A case analysis of alternative ICES concepts applied to a major metropolitan development complex is documented. The intent of this study is twofold: (1) to develop a framework for comparing ICES technologies to conventional energy supply systems and (2) to identify potential problems in the commercialization of new systems approaches to energy conservation. In brief, the ICES Program of the ERDA Office of Energy Conservation is intended to identify the opportunities for energy conservation in the community context through analysis, development, and/or demonstration of: location and design of buildings, building complexes, and infrastructure links; engineering and systems design of existing, emerging, and advanced energy production and delivery technologies and systems; regulatory designs for public planning, administration, and regulation of energy-conserving community development and energy services; and financial planning for energy-conserving community development and energy supply systems.

  14. Energy system impacts of desalination in Jordan

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg; Lund, Henrik; Mathiesen, Brian Vad

    2014-01-01

    and Multi Stage Flash (MSF) desalination driven by Cogeneration of Heat and Power (CHP). The two systems impact the energy systems in different ways due to the technologies’ particular characteristics. The systems are analyses in the energy systems analysis model EnergyPLAN to determine the impacts......Climate change mitigation calls for energy systems minimising end-use demands, optimising the fuel efficiency of conversion systems, increasing the use of renewable energy sources and exploiting synergies wherever possible. In parallel, global fresh water resources are strained due to amongst...... others population and wealth increase and competitive water uses from agriculture and industry is causing many nations to turn to desalination technologies. This article investigates a Jordanian energy scenario with two different desalination technologies; reverse osmosis (RO) driven by electricity...

  15. An energy saving system for hospital laundries

    Energy Technology Data Exchange (ETDEWEB)

    Katsanis, J.S.; Tsarabaris, P.T.; Polykrati, A.D.; Proios, A.N. [National Technical Univ. of Athens, Athens (Greece). School of Electrical and Computer Engineering; Koufakis, E.I. [Public Power Corp. S.A., Crete (Greece)

    2009-07-01

    Hospital laundries are one of the largest consumers of water and electrical and thermal energy. This paper examined the energy savings achieved by a system using the hot wastewater from the washing process. Hospital laundries consume thermal energy using steam, which is produced in boilers by burning diesel oil or natural gas. Electrical energy for the mechanical drives, ventilation and also the lighting required in the laundry area are big consumers of energy. The paper presented the proposed system and discussed the parameters of the system and system dimensioning. The paper also provided and discussed an interpretation of steam and energy savings. The proposed system was considered to be economically viable, simple in its construction, installation and operation. From the application of the suggested system, the cost savings resulted in a satisfactory payback period for the capital invested of approximately three to five years. 14 refs., 4 tabs., 2 figs.

  16. A simple scoring system for breast MRI interpretation: does it compensate for reader experience?

    International Nuclear Information System (INIS)

    Marino, Maria Adele; Clauser, Paola; Woitek, Ramona; Wengert, Georg J.; Kapetas, Panagiotis; Bernathova, Maria; Pinker-Domenig, Katja; Helbich, Thomas H.; Baltzer, Pascal A.T.; Preidler, Klaus

    2016-01-01

    To investigate the impact of a scoring system (Tree) on inter-reader agreement and diagnostic performance in breast MRI reading. This IRB-approved, single-centre study included 100 patients with 121 consecutive histopathologically verified lesions (52 malignant, 68 benign). Four breast radiologists with different levels of MRI experience and blinded to histopathology retrospectively evaluated all examinations. Readers independently applied two methods to classify breast lesions: BI-RADS and Tree. BI-RADS provides a reporting lexicon that is empirically translated into likelihoods of malignancy; Tree is a scoring system that results in a diagnostic category. Readings were compared by ROC analysis and kappa statistics. Inter-reader agreement was substantial to almost perfect (kappa: 0.643-0.896) for Tree and moderate (kappa: 0.455-0.657) for BI-RADS. Diagnostic performance using Tree (AUC: 0.889-0.943) was similar to BI-RADS (AUC: 0.872-0.953). Less experienced radiologists achieved AUC: improvements up to 4.7 % using Tree (P-values: 0.042-0.698); an expert's performance did not change (P = 0.526). The least experienced reader improved in specificity using Tree (16 %, P = 0.001). No further sensitivity and specificity differences were found (P > 0.1). The Tree scoring system improves inter-reader agreement and achieves a diagnostic performance similar to that of BI-RADS. Less experienced radiologists, in particular, benefit from Tree. (orig.)

  17. Limbic system, the main focus of dementia syndrome; A study with MRI and PET

    Energy Technology Data Exchange (ETDEWEB)

    Matsuzawa, Taiju [Morinosato Hospital, Atsugi, Kanagawa (Japan)

    1990-12-01

    Alzheimer disease and multi-infarct dementia are two entirely different diseases producing almost the same abnormalities as dementia syndrome. The statistical studies with MRI to locate the focus of dementia syndrome in the neocortex was an absolute failure. With MRI there is drastic atrophy and destruction of the amygdala and hippocampus suggesting the limbic system as the focus of dementia syndrome. Destruction of the limbic system in particular amygdala and hippocampus produced the functional obstruction brought about by the marked reduction in the glucose utilization with PET in the bilateral temporal, parietal and occipital association cortices. Although this type constitutes only about 1/5 of all dementia patients. It is considered the fundamental type of dementia syndrome. Aside from this, there is a type wherein simultaneous and symmetrical reductions in glucose utilization of the frontal association cortex and the motor association cortex in the anterior part of the neocortex. This is referred to as type II. It constitutes about 4/5 of all dementia patients which is far more than type I. Based on these results, it is thought that limbic system is the main focus of dementia syndrome. (author).

  18. SU-F-J-171: Robust Atlas Based Segmentation of the Prostate and Peripheral Zone Regions On MRI Utilizing Multiple MRI System Vendors

    International Nuclear Information System (INIS)

    Padgett, K; Pollack, A; Stoyanova, R; Swallen, A; Nelson, A

    2016-01-01

    Purpose: Automatically generated prostate MRI contours can be used to aid in image registration with CT or ultrasound and to reduce the burden of contouring for radiation treatment planning. In addition, prostate and zonal contours can assist to automate quantitative imaging features extraction and the analyses of longitudinal MRI studies. These potential gains are limited if the solutions are not compatible across different MRI vendors. The goal of this study is to characterize an atlas based automatic segmentation procedure of the prostate collected on MRI systems from multiple vendors. Methods: The prostate and peripheral zone (PZ) were manually contoured by an expert radiation oncologist on T2-weighted scans acquired on both GE (n=31) and Siemens (n=33) 3T MRI systems. A leave-one-out approach was utilized where the target subject is removed from the atlas before the segmentation algorithm is initiated. The atlas-segmentation method finds the best nine matched atlas subjects and then performs a normalized intensity-based free-form deformable registration of these subjects to the target subject. These nine contours are then merged into a single contour using Simultaneous Truth and Performance Level Estimation (STAPLE). Contour comparisons were made using Dice similarity coefficients (DSC) and Hausdorff distances. Results: Using the T2 FatSat (FS) GE datasets the atlas generated contours resulted in an average DSC of 0.83±0.06 for prostate, 0.57±0.12 for PZ and 0.75±0.09 for CG. Similar results were found when using the Siemens data with a DSC of 0.79±0.14 for prostate, 0.54±0.16 and 0.70±0.9. Contrast between prostate and surrounding anatomy and between the PZ and CG contours for both vendors demonstrated superior contrast separation; significance was found for all comparisons p-value < 0.0001. Conclusion: Atlas-based segmentation yielded promising results for all contours compared to expertly defined contours in both Siemens and GE 3T systems providing

  19. SU-F-J-171: Robust Atlas Based Segmentation of the Prostate and Peripheral Zone Regions On MRI Utilizing Multiple MRI System Vendors

    Energy Technology Data Exchange (ETDEWEB)

    Padgett, K; Pollack, A; Stoyanova, R [University of Miami, Miami, Florida (United States); Swallen, A; Nelson, A [MIM Software Inc., Cleveland, OH (United States)

    2016-06-15

    Purpose: Automatically generated prostate MRI contours can be used to aid in image registration with CT or ultrasound and to reduce the burden of contouring for radiation treatment planning. In addition, prostate and zonal contours can assist to automate quantitative imaging features extraction and the analyses of longitudinal MRI studies. These potential gains are limited if the solutions are not compatible across different MRI vendors. The goal of this study is to characterize an atlas based automatic segmentation procedure of the prostate collected on MRI systems from multiple vendors. Methods: The prostate and peripheral zone (PZ) were manually contoured by an expert radiation oncologist on T2-weighted scans acquired on both GE (n=31) and Siemens (n=33) 3T MRI systems. A leave-one-out approach was utilized where the target subject is removed from the atlas before the segmentation algorithm is initiated. The atlas-segmentation method finds the best nine matched atlas subjects and then performs a normalized intensity-based free-form deformable registration of these subjects to the target subject. These nine contours are then merged into a single contour using Simultaneous Truth and Performance Level Estimation (STAPLE). Contour comparisons were made using Dice similarity coefficients (DSC) and Hausdorff distances. Results: Using the T2 FatSat (FS) GE datasets the atlas generated contours resulted in an average DSC of 0.83±0.06 for prostate, 0.57±0.12 for PZ and 0.75±0.09 for CG. Similar results were found when using the Siemens data with a DSC of 0.79±0.14 for prostate, 0.54±0.16 and 0.70±0.9. Contrast between prostate and surrounding anatomy and between the PZ and CG contours for both vendors demonstrated superior contrast separation; significance was found for all comparisons p-value < 0.0001. Conclusion: Atlas-based segmentation yielded promising results for all contours compared to expertly defined contours in both Siemens and GE 3T systems providing

  20. Energy storage systems: power grid and energy market use cases

    Directory of Open Access Journals (Sweden)

    Komarnicki Przemysław

    2016-09-01

    Full Text Available Current power grid and market development, characterized by large growth of distributed energy sources in recent years, especially in Europa, are according energy storage systems an increasingly larger field of implementation. Existing storage technologies, e.g. pumped-storage power plants, have to be upgraded and extended by new but not yet commercially viable technologies (e.g. batteries or adiabatic compressed air energy storage that meet expected demands. Optimal sizing of storage systems and technically and economically optimal operating strategies are the major challenges to the integration of such systems in the future smart grid. This paper surveys firstly the literature on the latest niche applications. Then, potential new use case and operating scenarios for energy storage systems in smart grids, which have been field tested, are presented and discussed and subsequently assessed technically and economically.

  1. Impact of real-time virtual sonography, a coordinated sonography and MRI system that uses an image fusion technique, on the sonographic evaluation of MRI-detected lesions of the breast in second-look sonography.

    Science.gov (United States)

    Nakano, Shogo; Kousaka, Junko; Fujii, Kimihito; Yorozuya, Kyoko; Yoshida, Miwa; Mouri, Yukako; Akizuki, Miwa; Tetsuka, Rie; Ando, Takahito; Fukutomi, Takashi; Oshima, Yukihiko; Kimura, Junko; Ishiguchi, Tsuneo; Arai, Osamu

    2012-08-01

    The aim of this study was to verify the utility of second-look sonography using real-time virtual sonography (RVS)-a coordinated sonography with an MRI system that uses an image fusion technique with magnetic navigation-on the sonographic evaluation of MRI-detected lesions of the breast. Of the 196 consecutive patients who were examined with breast MRI in our hospital from 2006 to 2009, those patients who underwent second-look sonography to identify MRI-detected lesions were enrolled in this study. MRI was performed using a 1.5-T imager with the patient in a supine position. To assess the efficacy benefits of RVS, the correlations between lesion detection rates, MRI features, distribution, and histopathological classification on second-look sonography using conventional B-mode or RVS were analyzed. Of the 196 patients, 55 (28 %) demonstrated 67 lesions initially detected by MRI, followed by second-look sonography. Of the 67 MRI-detected lesions, 18 (30 %) were identified with second-look sonography using conventional B-mode alone, whereas 60 (90 %) lesions were detected with second-look sonography using RVS (p use of RVS on second-look sonography significantly increases the sonographic detection rate of MRI-detected lesions without operator dependence.

  2. Evaluation of femoral perfusion in a rabbit model of steroid-induced osteonecrosis by dynamic contrast-enhanced MRI with a high magnetic field MRI system.

    Science.gov (United States)

    Hayashi, Shigeki; Fujioka, Mikihiro; Ikoma, Kazuya; Saito, Masazumi; Ueshima, Keiichiro; Ishida, Masashi; Kuribayashi, Masaaki; Ikegami, Akira; Mazda, Osam; Kubo, Toshikazu

    2015-04-01

    To evaluate perfusion during the early phase after steroid administration in vivo using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with a high magnetic field MRI system. The main pathogenesis of steroid-induced osteonecrosis is considered to be ischemia. A single dose of methylprednisolone (MPSL) was injected into nine rabbits. DCE-MRI was performed for these rabbits before MPSL administration and 1, 5, 10, and 14 days after administration. Time-signal intensity curves were created for each femur based on the signal intensity to evaluate perfusion. Enhancement ratio (ER), initial slope (IS), and area under the curve (AUC) were calculated and the value before MPSL administration and the minimal value after administration were compared statistically. ER, IS, and AUC values after MPSL administration significantly decreased (P < 0.05, P < 0.01, and P < 0.01, respectively). All of them decreased by the 5th day in 56% of the femora and by the 14th day in 83%, and some femora even showed a decrease from the 1st day. In this study, decreased perfusion in the femora after steroid administration was proven. Additionally, we could show that it occurred from the early days after steroid administration. © 2014 Wiley Periodicals, Inc.

  3. MRI of the fingers in patients with systemic scleroderma. Early results of contrast-enhanced examinations on a dedicated MRI system

    International Nuclear Information System (INIS)

    Bonel, H.; Seemann, M.; Reiser, M.; Messer, G.; Walchner, M.; Roecken, M.

    1997-01-01

    Purpose. To estimate disease activity in patients with systemic sclerosis using contrast-enhanced MRI of the skin. Material and Methods. In a pre-study, sequences of a low-field (0.2 T) scanner (Artoscan, Esaote, Genova, Italy) were optimized for detection of intravenous contrast (0.1 mmol/l Gd-DTPA) in six patients with the autoimmune disease systemic scleroderma. Based on the results of the pre-study, 17 patients with scleroderma (7 sclerotic/10 active inflammatory disease) were scanned using gradient-spoiled 3D GRE sequences (FA 90 , TR 100 ms, TE 18 ms), which had been established as most sensitive for intravenous contrast. Contrast enhancement of the skin was determined quantitatively by contrast-to-noise ratios (CNR), comparing post- to pre-contrast and dynamic scans (for 6 min, 1 acquisition/min). Patients in the chronic state with sclerodactylia and active inflammation of the hands were considered separately and compared to a control group (n=10) matched according to age. Results. CNR increase after intravenous contrast was significantly higher in patients with active disease (86±16% increase) than sclerosing disease (29±3%, p [de

  4. First clinical experience with a dedicated MRI-guided high-intensity focused ultrasound system for breast cancer ablation

    Energy Technology Data Exchange (ETDEWEB)

    Merckel, Laura G.; Knuttel, Floor M.; Peters, Nicky H.G.M.; Mali, Willem P.T.M.; Bosch, Maurice A.A.J. van den [University Medical Center Utrecht, Department of Radiology, HP E 01.132, Utrecht (Netherlands); Deckers, Roel; Moonen, Chrit T.W.; Bartels, Lambertus W. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); Dalen, Thijs van [Diakonessenhuis Utrecht, Department of Surgery, Utrecht (Netherlands); Schubert, Gerald [Philips Healthcare, Best (Netherlands); Weits, Teun [Diakonessenhuis Utrecht, Department of Radiology, Utrecht (Netherlands); Diest, Paul J. van [University Medical Center Utrecht, Department of Pathology, Utrecht (Netherlands); Vaessen, Paul H.H.B. [University Medical Center Utrecht, Department of Anesthesiology, Utrecht (Netherlands); Gorp, Joost M.H.H. van [Diakonessenhuis Utrecht, Department of Pathology, Utrecht (Netherlands)

    2016-11-15

    To assess the safety and feasibility of MRI-guided high-intensity focused ultrasound (MR-HIFU) ablation in breast cancer patients using a dedicated breast platform. Patients with early-stage invasive breast cancer underwent partial tumour ablation prior to surgical resection. MR-HIFU ablation was performed using proton resonance frequency shift MR thermometry and an MR-HIFU system specifically designed for breast tumour ablation. The presence and extent of tumour necrosis was assessed by histopathological analysis of the surgical specimen. Pearson correlation coefficients were calculated to assess the relationship between sonication parameters, temperature increase and size of tumour necrosis at histopathology. Ten female patients underwent MR-HIFU treatment. No skin redness or burns were observed in any of the patients. No correlation was found between the applied energy and the temperature increase. In six patients, tumour necrosis was observed with a maximum diameter of 3-11 mm. In these patients, the number of targeted locations was equal to the number of areas with tumour necrosis. A good correlation was found between the applied energy and the size of tumour necrosis at histopathology (Pearson = 0.76, p = 0.002). Our results show that MR-HIFU ablation with the dedicated breast system is safe and results in histopathologically proven tumour necrosis. (orig.)

  5. Energy accounting in nuclear power systems

    International Nuclear Information System (INIS)

    Symonds, J.L.; Essam, P.; Stocks, K.

    1976-01-01

    Energy analysis is a systematic way of tracing and accounting for the flows of energy through an industrial system and apportioning a quantity of the primary energy input to each of the goods and services sent out. The application of energy accounting to nuclear power stations and their growth in generating systems is discussed. Misunderstandings arising from discrepancies and weaknesses in some published simple analyses of hypothetical growth situations are outlined. Results of a more complex energy flow analysis are used to demonstrate that current nuclear energy programs are running at an energy profit. Large fossil fuel savings will occur in a real electrical grid system under anticipated nuclear power growth rates. These savings will give a new dimension in planning the use of fossil energy resources which will still be needed for transport and industrial processes, such as steelmaking, for some time to come. (author)

  6. Energy accounting in nuclear power systems

    International Nuclear Information System (INIS)

    Symonds, J.L.; Essam, P.; Stocks, K.

    1975-10-01

    Energy analysis is a systematic way of tracing and accounting for the flows of energy through an industrial system and apportioning a quantity of the primary energy input of the goods and services sent out. The application of energy accounting to nuclear power stations and their growth in generating systems is discussed. Misunderstandings arising from discrepancies and weaknesses in some published simple analyses of hypothetical growth situations are outlined. Results of a more complex energy flow analysis are used to demonstrate that current nuclear energy programs are running at an energy profit. Large fossil fuel savings will occur in a real electrical grid system under anticipated nuclear power growth rates. These savings will give a new dimension in planning the use of fossil energy resources which will still be needed for transport and industrial processes, such as steel-making, for some time to come. (author)

  7. SU-E-T-20: Removal of Electron Contamination in Longitudinal Field MRI-Linac Systems: A Monte Carlo Study.

    Science.gov (United States)

    Oborn, B M; Metcalfe, P; Butson, M; Crozier, S; Keall, P

    2012-06-01

    The prototype inline MRI-linac system has some advantages over perpendicular models including avoiding the electron return effect. One of the disadvantages of the inline approach is the increased skin dose, estimated to be 400-1000% of the dmax dose. The purpose of this work was to design a feasible method to reduce this skin dose to acceptable levels. Magnetic modeling of proposed MRI-linac designs have been simulated with the inclusion of an optimized permanent magnet system to purge/deflect the electron contamination. The region of air above the phantom was also replaced with a helium bag (region of helium gas) and a beam scrapper below the deflector was added to collect deflected off-axis contamination. Monte Carlo simulations were then performed including the accurate 3D magnetic field maps. Surface dosimetry was recorded to verify the changes to the skin doses. Magnetic modelling showed that an optimized NdFeB permanent magnet system located outside the MRI coils (below the MLC's) can provide a strong enough region to purge/deflect a significant portion of the electron contamination from the x-ray beam. The impact on the MRI uniformity is around 100 ppm and hence is correctable via active/passive shimming of the MRI. The helium region also significantly limits the production of contamination traveling towards the phantom surface. Entry doses near CAX are predicted to be similar to the 0 T case. Magnetic and Monte Carlo modeling were performed to estimate the effect that a permanent magnet purging system, beam scrapper, and helium bag would have on lowering the skin doses in an inline MRI-Linac system. MRI non-uniformities introduced by the deflector could be corrected, contamination is mostly purged or blocked, and the helium bag minimizes air-generated contamination. As a result skin doses are comparable to having zero magnetic field. © 2012 American Association of Physicists in Medicine.

  8. Solar Energy Systems for Ohioan Residential Homeowners

    Science.gov (United States)

    Luckett, Rickey D.

    Dwindling nonrenewable energy resources and rising energy costs have forced the United States to develop alternative renewable energy sources. The United States' solar energy industry has seen an upsurge in recent years, and photovoltaic holds considerable promise as a renewable energy technology. The purpose of this case study was to explore homeowner's awareness of the benefits of solar energy. Disruptive-innovation theory was used to explore marketing strategies for conveying information to homeowners about access to new solar energy products and services. Twenty residential homeowners were interviewed face-to-face to explore (a) perceived benefits of solar energy in their county in Ohio, and (b) perceptions on the rationale behind the marketing strategy of solar energy systems sold for residential use. The study findings used inductive analyses and coding interpretation to explore the participants' responses that revealed 3 themes: the existence of environmental benefits for using solar energy systems, the expensive cost of equipment associated with government incentives, and the lack of marketing information that is available for consumer use. The implications for positive social change include the potential to enable corporate leaders, small business owners, and entrepreneurs to develop marketing strategies for renewable energy systems. These strategies may promote use of solar energy systems as a clean, renewable, and affordable alternative electricity energy source for the 21st century.

  9. Calculations of energy consumption in ventilation systems

    Energy Technology Data Exchange (ETDEWEB)

    Kreslins, Andris; Ramata, Anna [Riga Technical University (Latvia)], e-mail: kreslins@rbf.rtu.lv, email: Anna.Ramata@rtu.lv

    2011-07-01

    Energy cost is an important economic factor in the food industry production process. With the rising price of energy, a reduction in energy consumption would greatly impact production and the end product. The aim of this study was to develop a methodology for optimizing energy consumption. A comparison between a traditional ventilation system and a mechanical system was carried out; the necessary enthalpy for heating the air supply and thermal energy consumption were calculated and compared for both systems during the heating season, from October to April, using climatological data for Latvia. Results showed that energy savings of 46% to 87% can be achieved by applying the methodology in the design of industrial buildings; in addition, a well-designed ventilation system increases the workers' productivity. This study presented a methodology which can optimize energy consumption in the food industry sector.

  10. Energy information systems: a general overview

    International Nuclear Information System (INIS)

    Sen, B.K.

    1991-01-01

    The unprecedented energy crises that engulfed the world in early 1970s brought about a spurt in energy research all over the world, which in turn caused the rapid growth of literature in the field. In order to achieve effective bibliographical control, proper dissemination of information, and rapid access to the desired document, energy information systems of diverse scope came into being. The paper describes the special features of several information systems like (i) International Nuclear Information Systems, which covers world literature on nuclear science and technology (ii) Energy Information Services which takes cares of energy information transfer among the Commonwealth countries of the Asia and Pacific region; (ii) Information Network on New Energy Sources and Technologies for Asia And Pacific. This system is being developed to ensure smooth energy information transfer amongst non-commonwealth countries of Asia and the Pacific. (author)

  11. Energy system impacts of desalination in Jordan

    Directory of Open Access Journals (Sweden)

    Poul Alberg Østergaard

    2014-02-01

    Full Text Available Climate change mitigation calls for energy systems minimising end-use demands, optimising the fuel efficiency of conversion systems, increasing the use of renewable energy sources and exploiting synergies wherever possible. In parallel, global fresh water resources are strained due to amongst others population and wealth increase and competitive water uses from agriculture and industry is causing many nations to turn to desalination technologies. This article investigates a Jordanian energy scenario with two different desalination technologies; reverse osmosis (RO driven by electricity and Multi Stage Flash (MSF desalination driven by Cogeneration of Heat and Power (CHP. The two systems impact the energy systems in different ways due to the technologies’ particular characteristics. The systems are analyses in the energy systems analysis model EnergyPLAN to determine the impacts on energy system performance. Results indicate that RO and MSF are similar in fuel use. While there is no use of waste heat from condensing mode plants, efficiencies for CHP and MSF are not sufficiently good to results in lower fuel usage than RO. The Jordanian energy system is somewhat inflexible giving cause to Critical Excess Electricity Production (CEEP even at relatively modest wind power penetrations. Here RO assists the energy system in decreasing CEEP – and even more if water storage is applied.

  12. Risk management and energy systems

    International Nuclear Information System (INIS)

    Carlevaro, F.; Romerio, F.

    1992-01-01

    In five sessions the following topics were dealt with: risk problems, risk analysis and evaluation tools, risks in industrial societies, risks of energy production, technological risks, ethics and political-social consensus. figs., tabs., refs

  13. Energy analysis of power systems

    International Nuclear Information System (INIS)

    2004-01-01

    Next to economic viability, the holistic energy balance of electricity generation options' is a factor of major importance. All aspects of the energy balance, i. e. all expenditures and all revenues, are compared in a life cycle analysis. This turns out to be a complex task, especially because of the large number of input quantities to be determined, including the balancing limits to be taken into account. The article presents in detail the findings of analyses of energy balances for various types of nuclear power plants as well as electricity generation in fossil-fired power plants, and for renewable energies. The analyses and their databases are discussed. Moreover, the findings are presented for the energetic amortization periods and the amounts of CO 2 emissions specific to the respective generating technologies. (orig.)

  14. Facilitating energy transition through energy commons : An application of socio-ecological systems framework for integrated community energy systems

    NARCIS (Netherlands)

    Acosta, Cristina; Ortega, Mariana; Bunsen, Till; Koirala, B.P.; Ghorbani, A.

    2018-01-01

    Integrated Community Energy Systems (ICES) are an emerging local energy system focusing on the collective use of distributed energy resources (DER). These socio-technical systems (STSs) have a high potential to advance the transition towards socially inclusive, environmentally-friendly energy

  15. Facilitating energy transition through energy commons : An application of socio-ecological systems framework for integrated community energy systems

    NARCIS (Netherlands)

    Acosta, Cristina; Ortega, Mariana; Bunsen, Till; Koirala, Binod Prasad; Ghorbani, Amineh

    2018-01-01

    Integrated Community Energy Systems (ICES) are an emerging local energy system focusing on the collective use of distributed energy resources (DER). These socio-technical systems (STSs) have a high potential to advance the transition towards socially inclusive, environmentally-friendly energy

  16. TU-AB-BRA-07: Distortion-Free 3D Diffusion MRI On An MRI-Guided Radiotherapy System for Longitudinal Tumor Response Assessment

    International Nuclear Information System (INIS)

    Gao, Y; Yang, Y; Rangwala, N; Cao, M; Low, D; Hu, P

    2016-01-01

    Purpose: To develop a reliable, 3D distortion-free diffusion MRI technique for longitudinal tumor response assessment and MRI-guided adaptive radiotherapy(RT). Methods: A diffusion prepared 3D turbo spin echo readout (DP-TSE) sequence was developed and compared with the conventional diffusion-weighted single-shot echo-planar-imaging (DW-ssEPI) sequence in a commercially available diffusion phantom, and one head-and-neck and one brain cancer patient on an MRI-guided RT system (ViewRay). In phantom study, the geometric fidelity was quantified as the ratio between the left-right (RL) and anterior-posterior (AP) dimension. Ten slices were measured on DP-TSE, DW-ssEPI and standard TSE images where the later was used as the geometric reference. ADC accuracy was verified at both 0°C (reference ADC available) and room temperature with a range of diffusivity between 0.35 and 2.0*10"−"3mm"2/s. The ADC reproducibility was assessed based on 8 room-temperature measurements on 6 different days. In the pilot single-slice in-vivo study, CT images were used as the geometric reference, and ADC maps from both diffusion sequences were compared. Results: Distortion and susceptive-related artifact were severe in DW-ssEPI, with significantly lower RL/AP ratio (0.9579±0.0163) than DP-TSE (0.9990±0.0031) and TSE (0.9995±0.0031). ADCs from the two diffusion sequences both matched well with the vendor-provided values at 0°C; however DW-ssEPI fails to provide accurate ADC for high diffusivity vials at room temperature due to high noise level (10 times higher than DP-TSE). The DP-TSE sequence had excellent ADC reproducibility with <4% ADC variation among 8 separate measurements. In patient study, DP-TSE exhibited substantially improved geometric reliability. ROI analysis in ADC maps generated from DP-TSE and DW-ssEPI showed <5% difference where high b-value images were excluded from the latter approach due to excessive noise level. Conclusion: A diffusion MRI sequence with excellent

  17. TU-AB-BRA-07: Distortion-Free 3D Diffusion MRI On An MRI-Guided Radiotherapy System for Longitudinal Tumor Response Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Y; Yang, Y; Rangwala, N; Cao, M; Low, D; Hu, P [UCLA School of Medicine, Los Angeles, CA (United States)

    2016-06-15

    Purpose: To develop a reliable, 3D distortion-free diffusion MRI technique for longitudinal tumor response assessment and MRI-guided adaptive radiotherapy(RT). Methods: A diffusion prepared 3D turbo spin echo readout (DP-TSE) sequence was developed and compared with the conventional diffusion-weighted single-shot echo-planar-imaging (DW-ssEPI) sequence in a commercially available diffusion phantom, and one head-and-neck and one brain cancer patient on an MRI-guided RT system (ViewRay). In phantom study, the geometric fidelity was quantified as the ratio between the left-right (RL) and anterior-posterior (AP) dimension. Ten slices were measured on DP-TSE, DW-ssEPI and standard TSE images where the later was used as the geometric reference. ADC accuracy was verified at both 0°C (reference ADC available) and room temperature with a range of diffusivity between 0.35 and 2.0*10{sup −3}mm{sup 2}/s. The ADC reproducibility was assessed based on 8 room-temperature measurements on 6 different days. In the pilot single-slice in-vivo study, CT images were used as the geometric reference, and ADC maps from both diffusion sequences were compared. Results: Distortion and susceptive-related artifact were severe in DW-ssEPI, with significantly lower RL/AP ratio (0.9579±0.0163) than DP-TSE (0.9990±0.0031) and TSE (0.9995±0.0031). ADCs from the two diffusion sequences both matched well with the vendor-provided values at 0°C; however DW-ssEPI fails to provide accurate ADC for high diffusivity vials at room temperature due to high noise level (10 times higher than DP-TSE). The DP-TSE sequence had excellent ADC reproducibility with <4% ADC variation among 8 separate measurements. In patient study, DP-TSE exhibited substantially improved geometric reliability. ROI analysis in ADC maps generated from DP-TSE and DW-ssEPI showed <5% difference where high b-value images were excluded from the latter approach due to excessive noise level. Conclusion: A diffusion MRI sequence with

  18. Energy database system of NEDO

    International Nuclear Information System (INIS)

    Kimura, Noburu

    1990-01-01

    As to the offer of technical information and others to foreign countries by Japan, the state of more import than export has been criticized internationally. The NEDO energy data base explained in this report is to make the international contribution of information, and based on the Energy Technology Data Exchange Agreement concluded between 13 countries taking part in the IEA and France, the participating countries offer their own technical information on energy, the operating organization collects them and makes the data base, and NEDO systematizes it for distribution. The IEA and the activities of exchanging information, the course of starting the Energy Technology Data Exchange Agreement and its contents, and the works of NEDO based on the Agreement are described. As for the literatures which are not sold on the market, their texts are exchanged. As to the composition of the data base, according to the example in 1988, about 1/3 were directly related to energy, and the rest 2/3 were indirectly related to energy technology. The features of the data base and the method of its utilization are explained. (K.I.)

  19. Fetal lung volume measurement by MRI with high-speed imaging systems

    Energy Technology Data Exchange (ETDEWEB)

    Osada, Hisao; Kaku, Kenshi [Chiba Univ. (Japan). Hospital

    2002-08-01

    Although ultrasonography is widely used for fetal morphologic observation, magnetic resonance imaging (MRI) has gained popularity as a new prenatal diagnostic method with recent introduction of high-speed imaging systems. Infants with lung hypoplasia affecting respiratory function require intensive management starting immediately after birth. Therefore, accurate prenatal differential diagnosis and severity evaluation are extremely important for these fetuses. The aim of this study is to measure fetal lung volume using a computer-based, three-dimensional MRI imaging system and to evaluate the possibility of clinical applications of this procedure. A total of 96 fetuses were evaluated, all were morphologically abnormal, and MRI was done for advanced assessment from 24 to 39 weeks gestation. Three-directional views of fetal chest were imaged by Signa Horizon, 1.5 Tesla, version 5.6 (General Electronics) with the following conditions; coil: TORSO coil, sequence: SSFSE (single shot fast spin echo), slice thickness: 5 mm, and imaging speed: 2 seconds/slice. To calculate the lung volume and create three-dimensional image, the lung area in each slice was traced out, then multiplied using computer image processing. Simultaneously, the volumes of all slices were summed to give the volume of each lung. Linear regression analysis and analysis of covariance (ANCOVA) were used for statistical analyses. In all cases, clear images were obtained, and were adequate for three-dimensional evaluation of the fetal lung. Thirty-five fetuses had poor outcomes, such as intrauterine fetal death, neonatal death, and intensive respiratory care. Regression lines of lung volume versus gestational week were calculated for these fetuses with poor outcome and 61 other fetuses with good outcome. ANCOVA, with gestational week as a covariant, revealed a significant intergroup difference in the lung volume (p<0.001). Similarly, regression lines of lung volume versus fetal body weight estimated by

  20. Energy efficiency and pulmonary artery flow after balloon pulmonary angioplasty for inoperable, chronic thromboembolic pulmonary hypertension: Analysis by phase-contrast MRI

    Energy Technology Data Exchange (ETDEWEB)

    Nagao, Michinobu, E-mail: nagao.michinobu@twmu.ac.jp [Department of Diagnostic Imaging & Nuclear Medicine, Tokyo Women’s Medical University, Tokyo (Japan); Yamasaki, Yuzo [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Abe, Kohtaro; Hosokawa, Kazuya [Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Kawanami, Satoshi [Department of Molecular Imaging & Diagnosis, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Kamitani, Takeshi; Yamanouchi, Torahiko [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Yabuuchi, Hidetake [Department of Medical Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Fukushima, Kenji [Department of Diagnostic Imaging & Nuclear Medicine, Tokyo Women’s Medical University, Tokyo (Japan); Honda, Hiroshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)

    2017-02-15

    Purpose: The aims of this study were to propose a new quantitative method for pulmonary artery (PA) flow energetics using phase-contrast magnetic resonance imaging (PC-MRI), and to investigate how balloon pulmonary angioplasty (BPA) impacts energetics in chronic thromboembolic pulmonary hypertension (CTEPH). Materials and methods: PC-MRI at 3-Teslar and with a flow sensitive gradient echo was used to examine energetics prior to and following BPA for 24 CTEPH patients. Stroke volume (m; ml) and mean velocity (V; mm/s) for the main pulmonary artery (PA), right PA, and left PA were calculated from a time-flow curve derived from PC-MRI. Based on the Bernoulli principle, PA energy was identified as 1/2 mV{sup 2} (μj/kg), and energy loss was defined as the following equation “energy loss = main PA energy − (rt. PA energy + lt. PA energy)”. Results: Right PA energy was significantly greater post-BPA than pre-BPA (61 ± 55 vs. 32 ± 40 μj/kg). There was no difference in main PA and left PA energies. Energy loss was significantly decreased post-BPA (18 ± 97 μj/kg) than pre-BPA (79 ± 125 μj/kg). An optimal cutoff of left PA energy of 45 μj/kg pre-BPA can be used to predict patients with mPAP ≥ 30 mmHg after BPA, with an area under the curve of 0.91, 78% sensitivity, and 92% specificity. Conclusion: Analysis of PA energetics using phase-contrast MRI demonstrates that BPA improves energy loss in CTEPH. In addition, BPA responses can be predicted by PA energy status pre-treatment.

  1. Distributed energy systems with wind power and energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Korpaas, Magnus

    2004-07-01

    The topic of this thesis is the study of energy storage systems operating with wind power plants. The motivation for applying energy storage in this context is that wind power generation is intermittent and generally difficult to predict, and that good wind energy resources are often found in areas with limited grid capacity. Moreover, energy storage in the form of hydrogen makes it possible to provide clean fuel for transportation. The aim of this work has been to evaluate how local energy storage systems should be designed and operated in order to increase the penetration and value of wind power in the power system. Optimization models and sequential and probabilistic simulation models have been developed for this purpose. Chapter 3 presents a sequential simulation model of a general wind hydrogen energy system. Electrolytic hydrogen is used either as a fuel for transportation or for power generation in a stationary fuel cell. The model is useful for evaluating how hydrogen storage can increase the penetration of wind power in areas with limited or no transmission capacity to the main grid. The simulation model is combined with a cost model in order to study how component sizing and choice of operation strategy influence the performance and economics of the wind-hydrogen system. If the stored hydrogen is not used as a separate product, but merely as electrical energy storage, it should be evaluated against other and more energy efficient storage options such as pumped hydro and redox flow cells. A probabilistic model of a grid-connected wind power plant with a general energy storage unit is presented in chapter 4. The energy storage unit is applied for smoothing wind power fluctuations by providing a firm power output to the grid over a specific period. The method described in the chapter is based on the statistical properties of the wind speed and a general representation of the wind energy conversion system and the energy storage unit. This method allows us to

  2. Correlation between anatomic foot and ankle movement measured with MRI and with a motion analysis system.

    Science.gov (United States)

    Marquez-Barrientos, C; Liu, X C; Lyon, R; Tassone, C; Thometz, J; Tarima, S

    2012-07-01

    Several studies have attempted to measure how well external markers track internal bone movement using pins drilled into the foot, but this is too invasive for the pediatric population. This study investigated how well a six segment foot model (6SFM) using external markers was able to measure bone movement in the foot compared to MRI measurements. The foot was moved into different positions using a plastic foot jig and measurements were taken with both systems. The aims were to: (1) Look at the correlation between movement tracked with an Electronic Motion Tracking System (EMTS) and by measurements derived from MRI images, specifically the principal intercept angles (PIAs) which are the angles of intersection between principal axes of inertia of bone volumes. (2) To see how well external motion measured by the 6SFM could predict PIAs. Four bone pairs had their movement tracked: Tibia-Calcaneus, Calcaneus-Cuboid, Navicular-1st Metatarsal, and 1st Metatarsal-Hallux. The results showed moderate correlation between measured PIAs and those predicted at the Tibia-Calcaneus, Navicular-1st Metatarsal, and 1st Metatarsal-Hallux joints. Moderate to high correlation was found between the PIA and movement in a single anatomic plane for all four joints at several positions. The 6SFM using the EMTS allows reliable tracking of 3D rotations in the pediatric foot, except at the Calcaneus-Cuboid joint. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Concurrent TMS-fMRI Reveals Interactions between Dorsal and Ventral Attentional Systems

    DEFF Research Database (Denmark)

    Leitao, Joana; Thielscher, Axel; Tuennerhoff, Johannes

    2015-01-01

    interactively in this process. This fMRI study used concurrent transcranial magnetic stimulation (TMS) as a causal perturbation approach to investigate the interactions between dorsal and ventral attentional systems and sensory processing areas. In a sustained spatial attention paradigm, human participants......Adaptive behavior relies on combining bottom-up sensory inputs with top-down control signals to guide responses in line with current goals and task demands. Over the past decade, accumulating evidence has suggested that the dorsal and ventral frontoparietal attentional systems are recruited......-TMS relative to Sham-TMS increased activation in the parietal cortex regardless of sensory stimulation, confirming the neural effectiveness of TMS stimulation. Visual targets increased activations in the anterior insula, a component of the ventral attentional system responsible for salience detection...

  4. Programming models for energy-aware systems

    Science.gov (United States)

    Zhu, Haitao

    Energy efficiency is an important goal of modern computing, with direct impact on system operational cost, reliability, usability and environmental sustainability. This dissertation describes the design and implementation of two innovative programming languages for constructing energy-aware systems. First, it introduces ET, a strongly typed programming language to promote and facilitate energy-aware programming, with a novel type system design called Energy Types. Energy Types is built upon a key insight into today's energy-efficient systems and applications: despite the popular perception that energy and power can only be described in joules and watts, real-world energy management is often based on discrete phases and modes, which in turn can be reasoned about by type systems very effectively. A phase characterizes a distinct pattern of program workload, and a mode represents an energy state the program is expected to execute in. Energy Types is designed to reason about energy phases and energy modes, bringing programmers into the optimization of energy management. Second, the dissertation develops Eco, an energy-aware programming language centering around sustainability. A sustainable program built from Eco is able to adaptively adjusts its own behaviors to stay on a given energy budget, avoiding both deficit that would lead to battery drain or CPU overheating, and surplus that could have been used to improve the quality of the program output. Sustainability is viewed as a form of supply and demand matching, and a sustainable program consistently maintains the equilibrium between supply and demand. ET is implemented as a prototyped compiler for smartphone programming on Android, and Eco is implemented as a minimal extension to Java. Programming practices and benchmarking experiments in these two new languages showed that ET can lead to significant energy savings for Android Apps and Eco can efficiently promote battery awareness and temperature awareness in real

  5. Sustainable Energy, Water and Environmental Systems

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg; Duic, Neven

    2014-01-01

    This issue presents research results from the 8th Conference on Sustainable Development of Energy, Water and Environment Systems – SDEWES - held in Dubrovnik, Croatia in 2013. Topics covered here include the energy situation in the Middle East with a focus in Cyprus and Israel, energy planning me...

  6. Smart and usable home energy management systems

    NARCIS (Netherlands)

    Van Dam, S.S.

    2009-01-01

    This paper reviews research into Home Energy Management Systems (HEMS). These are intermediary products that can visualize, manage, and/or monitor the energy use of other products or whole households. HEMS have lately received increasing attention for their possible role in conserving energy within

  7. Combined solar collector and energy storage system

    Science.gov (United States)

    Jensen, R. N. (Inventor)

    1980-01-01

    A combined solar energy collector, fluid chiller and energy storage system is disclosed. A movable interior insulated panel in a storage tank is positionable flush against the storage tank wall to insulate the tank for energy storage. The movable interior insulated panel is alternately positionable to form a solar collector or fluid chiller through which the fluid flows by natural circulation.

  8. Energy Systems Integration: Demonstrating Distributed Resource Communications

    Energy Technology Data Exchange (ETDEWEB)

    2017-01-01

    Overview fact sheet about the Electric Power Research Institute (EPRI) and Schneider Electric Integrated Network Testbed for Energy Grid Research and Technology Experimentation (INTEGRATE) project at the Energy Systems Integration Facility. INTEGRATE is part of the U.S. Department of Energy's Grid Modernization Initiative.

  9. Real-time 3-dimensional virtual reality navigation system with open MRI for breast-conserving surgery

    International Nuclear Information System (INIS)

    Tomikawa, Morimasa; Konishi, Kozo; Ieiri, Satoshi; Hong, Jaesung; Uemura, Munenori; Hashizume, Makoto; Shiotani, Satoko; Tokunaga, Eriko; Maehara, Yoshihiko

    2011-01-01

    We report here the early experiences using a real-time three-dimensional (3D) virtual reality navigation system with open magnetic resonance imaging (MRI) for breast-conserving surgery (BCS). Two patients with a non-palpable MRI-detected breast tumor underwent BCS under the guidance of the navigation system. An initial MRI for the breast tumor using skin-affixed markers was performed immediately prior to excision. A percutaneous intramammary dye marker was applied to delineate an excision line, and the computer software '3D Slicer' generated a real-time 3D virtual reality model of the tumor and the puncture needle in the breast. Under guidance by the navigation system, marking procedures were performed without any difficulties. Fiducial registration errors were 3.00 mm for patient no.1, and 4.07 mm for patient no.2. The real-time 3D virtual reality navigation system with open MRI is feasible for safe and accurate excision of non-palpable MRI-detected breast tumors. (author)

  10. Five paradox on energy system management

    International Nuclear Information System (INIS)

    Frisch, J.R.

    1995-01-01

    Five paradox are detailed on energy management: internationalization of energy questions but always regional management is present, short term problems must be solved but without forgetting long term problems in environment, the third paradox is : we have time but we are in a hurry, we have reserves but ten, twenty or thirty years are necessary to adapt our energy system; the fourth paradox is : we cannot manage energy by managing only energy, for example : finances system development and environment importance. The last and fifth paradox is : the market, yes, but state too, as regulative force

  11. Energy Systems Modelling Research and Analysis

    DEFF Research Database (Denmark)

    Møller Andersen, Frits; Alberg Østergaard, Poul

    2015-01-01

    This editorial introduces the seventh volume of the International Journal of Sustainable Energy Planning and Management. The volume presents part of the outcome of the project Energy Systems Modelling Research and Analysis (ENSYMORA) funded by the Danish Innovation Fund. The project carried out b...... by 11 university and industry partners has improved the basis for decision-making within energy planning and energy scenario making by providing new and improved tools and methods for energy systems analyses.......This editorial introduces the seventh volume of the International Journal of Sustainable Energy Planning and Management. The volume presents part of the outcome of the project Energy Systems Modelling Research and Analysis (ENSYMORA) funded by the Danish Innovation Fund. The project carried out...

  12. Nuclear Hybrid Energy Systems: Challenges and Opportunities

    Energy Technology Data Exchange (ETDEWEB)

    P. Sabharwall; S.B. Sitton; S.J. Yoon; C. Stoots

    2014-07-01

    With growing demand of energy and costs of the fossil fuels, coupled with the environmental concerns have resulted in an increased interest in alternative energy sources. Nuclear hybrid energy systems (NHES) are being considered which incorporates renewable energy sources such as solar and wind energy combined with nuclear reactor and energy storage to meet the peak hours demand imposed on the grid, along with providing process heat for other potential industrial applications. This concept could potentially satisfy various energy demands and improve reliability, robustness and resilience for the entire system as a whole, along with economic and net efficiency gains. This paper provides a brief understanding of potential NHES system and architecture along with the challenges

  13. Thermal Distribution System | Energy Systems Integration Facility | NREL

    Science.gov (United States)

    Thermal Distribution System Thermal Distribution System The Energy Systems Integration Facility's . Photo of the roof of the Energy Systems Integration Facility. The thermal distribution bus allows low as 10% of its full load level). The 60-ton chiller cools water with continuous thermal control

  14. Implementation of Renewable Energy Systems in Denmark

    DEFF Research Database (Denmark)

    Meyer, Niels I

    1997-01-01

    Denmark has been one of the first countries in the world to commit itself to a sustainable energy development. This has been substantiated by two official action plans from 1990 and 1996 with emphasis on energy efficiency and supply systems based on renewable energy. In year 2005, renewable energy...... sources are planned to cover 12-14% and in year 2030 about 35% of total Danish energy demand. This paper reviews the experiences with implementation of renewable energy in Denmark with a focus on wind power and biomass....

  15. An energy storage and regeneration system

    DEFF Research Database (Denmark)

    2006-01-01

      The present invention relates to a method and a system for storing excess energy produced by an electric power plant during periods of lower energy demand than the power plant production capacity. The excess energy is stored by hydrolysis of water and storage of hydrogen and oxygen in underground...... caverns. When the energy demand exceeds the power production capacity of the plant, the stored gases are burned and the thermal energy is converted into electricity in gas turbine generators. The regenerated electrical power is then used to supplement the output of the electric power plant to meet...... the higher level of energy demand....

  16. Microelectronic circuit design for energy harvesting systems

    CERN Document Server

    Di Paolo Emilio, Maurizio

    2017-01-01

    This book describes the design of microelectronic circuits for energy harvesting, broadband energy conversion, new methods and technologies for energy conversion. The author also discusses the design of power management circuits and the implementation of voltage regulators. Coverage includes advanced methods in low and high power electronics, as well as principles of micro-scale design based on piezoelectric, electromagnetic and thermoelectric technologies with control and conditioning circuit design. Provides a single-source reference to energy harvesting and its applications; Serves as a practical guide to microelectronics design for energy harvesting, with application to mobile power supplies; Enables readers to develop energy harvesting systems for wearable/mobile electronics.

  17. ADVANCES IN ZERO ENERGY TRANSPORTATION SYSTEMS

    OpenAIRE

    Ahmad, Othman

    2017-01-01

    Hyperloop mass transportation systems are activelydeveloped at the moment. They represent the forefront development of the ZeroEnergy Transportation systems where air drag is minimized by travelling in avacuum and friction is reduced by non-contact bearings. Hyperloop supportersare confident that the cost of their transportation systems would be lowcompared to existing transportation systems because of the low loss andtherefore low energy consumption as well as other cost-saving techniquesdoc...

  18. Comparative risk assessment of total energy systems

    International Nuclear Information System (INIS)

    Soerensen, B.

    1982-01-01

    The paper discusses a methodology for total impact assessment of energy systems, ideally evaluating all the impacts that a given energy system has on the society in which it is imbedded or into which its introduction is being considered. Impacts from the entire energy conversion chain ('fuel cycle' if the system is fuel-based), including energy storage, transport and transmission, as well as the institutions formed in order to manage the system, should be compared on the basis of the energy service provided. A number of impacts are considered, broadly classified as impacts on satisfaction of biological needs, on health, on environment, on social relations and on the structure of society. Further considerations include impacts related to cost and resilience, and, last but not least, impacts on global relations. The paper discusses a number of published energy studies in the light of the comparative impact assessment methodology outlined above. (author)

  19. Biodigester as an energy storage system

    Energy Technology Data Exchange (ETDEWEB)

    Borges Neto, M.R.; Lopes, L.C.N. [Federal Institute of Education, Science and Technology of Sertao Pernambucano (IFSertao-PE), Petrolina, PE (Brazil)], Emails: rangel@cefetpet.br; Pinheiro Neto, J.S.; Carvalho, P.C.M. [Federal University of Ceara (UFC), Fortaleza, CE (Brazil). Dept. of Electrical Engineering], Emails: neto@tbmtextil.com.br, carvalho@dee.ufc.br; Silveira, G.C.; Moreira, A.P.; Borges, T.S.H. [Federal Institute of Education, Science and Technology of Ceara (IFCE), Fortaleza, CE (Brazil)], Emails: gcsilveira@cefet-ce.br, apmoreira@ifce.edu.br, thatyanys@yahoo.com.br

    2009-07-01

    Electricity supply for rural and remote areas is becoming an increasing priority to developing countries. The high initial cost of renewable energy based unities usually needs an energy storage system; due its operational and even replacement cost contributes to a higher final cost. The choice of energy storage systems depends on the sort and size of adopted power supply. This paper has a main goal to introduce a renewable energy based storage system weakly explored in Brazil: biogas from anaerobic digestion. It also brings a review of the main energy storage systems applied to electrical energy generation. As reference an experiment with an adapted Indian digester of 5 m{sup 3} that produced nearly 2m{sup 3} of biogas daily. The obtained biogas met the consumption of at least 4 typical Brazilian low income households with installed load of 500 W each and was enough to replace the use of 420 Ah lead-acid batteries. (author)

  20. Wind energy systems information user study

    Energy Technology Data Exchange (ETDEWEB)

    Belew, W.W.; Wood, B.L.; Marle, T.L.; Reinhardt, C.L.

    1981-01-01

    This report describes the results of a series of telephone interviews with potential users of information on wind energy conversion. These interviews, part of a larger study covering nine different solar technologies, attempted to identify: the type of information each distinctive group of information users needed, and the best way of getting information to that group. Groups studied include: wind energy conversion system researchers; wind energy conversion system manufacturer representatives; wind energy conversion system distributors; wind turbine engineers; utility representatives; educators; county agents and extension service agents; and wind turbine owners.

  1. Restructuring the Energy System. Report of the Energy Commission

    International Nuclear Information System (INIS)

    1995-01-01

    The commission was instructed to examine the current energy policy programs for restructuring and developing the energy system (i.e. phasing out nuclear power and moving to renewable sources) and to analyze the needs for changes; to propose measures for ensuring an efficient electricity supply under the new conditions of a liberalized electricity market; and to present proposals for a schedule for reorganizing the energy system. The report gives a full picture of the Swedish energy system including supply, consumption, prices, environmental impacts, R and D, and international aspects. The commission concludes that one nuclear power plant can be closed during the 1990's without upsetting the power balances. Phasing out all nuclear plants by year 2010 will create problems with the price levels of electricity supply, and will conflict with the CO 2 reduction objective. The proposals for economic control measures for performing the restructuring include: An environmental bonus (or investment support) for environmentally sound electricity production financed by an electricity tax, a tax on nuclear power increasing with the age of the reactors, a reorganization fund to finance new and environmentally acceptable electricity production. Also, energy research should be allotted greater resources, in particular for new technology for electricity production. The commission points towards the possibilities for reducing energy consumption, and especially electricity consumption. Space heating should gradually move away from electric heating. Examples are given on measures for improving energy efficiency and problems with financing such measures should be studied

  2. Energy accounting and optimization for mobile systems

    Science.gov (United States)

    Dong, Mian

    Energy accounting determines how much a software process contributes to the total system energy consumption. It is the foundation for evaluating software and has been widely used by operating system based energy management. While various energy accounting policies have been tried, there is no known way to evaluate them directly simply because it is hard to track every hardware use by software in a heterogeneous multi-core system like modern smartphones and tablets. In this thesis, we provide the ground truth for energy accounting based on multi-player game theory and offer the first evaluation of existing energy accounting policies, revealing their important flaws. The proposed ground truth is based on Shapley value, a single value solution to multi-player games of which four axiomatic properties are natural and self-evident to energy accounting. To obtain the Shapley value-based ground truth, one only needs to know if a process is active during the time under question and the system energy consumption during the same time. We further provide a utility optimization formulation of energy management and show, surprisingly, that energy accounting does not matter for existing energy management solutions that control the energy use of a process by giving it an energy budget, or budget based energy management (BEM). We show an optimal energy management (OEM) framework can always outperform BEM. While OEM does not require any form of energy accounting, it is related to Shapley value in that both require the system energy consumption for all possible combination of processes under question. We provide a novel system solution that meet this requirement by acquiring system energy consumption in situ for an OS scheduler period, i.e.,10 ms. We report a prototype implementation of both Shapley value-based energy accounting and OEM based scheduling. Using this prototype and smartphone workload, we experimentally demonstrate how erroneous existing energy accounting policies can

  3. Hydrogen based energy storage for solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Vanhanen, J.P.; Hagstroem, M.T.; Lund, P.H. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics; Leppaenen, J.R.; Nieminen, J.P. [Neste Oy (Finland)

    1998-12-31

    Hydrogen based energy storage options for solar energy systems was studied in order to improve their overall performance. A 1 kW photovoltaic hydrogen (PV-H2) pilot-plant and commercial prototype were constructed and a numerical simulation program H2PHOTO for system design and optimisation was developed. Furthermore, a comprehensive understanding of conversion (electrolysers and fuel cells) and storage (metal hydrides) technologies was acquired by the project partners. The PV-H{sub 2} power system provides a self-sufficient solution for applications in remote locations far from electric grids and maintenance services. (orig.)

  4. Expected energy production evaluation for photovoltaic systems

    DEFF Research Database (Denmark)

    Ding, Yi; Østergaard, Jacob; Peng, Wang

    2011-01-01

    A photovoltaic (PV) system consists of many solar panels, which are connected in series, parallel or a combination of both. Energy production for the PV system with various configurations is different. In this paper, a methodology is developed to evaluate and analyze the expected energy production...

  5. Energy system impacts of desalination in Jordan

    OpenAIRE

    Poul Alberg Østergaard; Henrik Lund; Brian Vad Mathiesen

    2014-01-01

    Climate change mitigation calls for energy systems minimising end-use demands, optimising the fuel efficiency of conversion systems, increasing the use of renewable energy sources and exploiting synergies wherever possible. In parallel, global fresh water resources are strained due to amongst others population and wealth increase and competitive water uses from agriculture and industry is causing many nations to turn to desalination technologies. This article investigatesa Jordanian energy sc...

  6. Energy consumption in the food supply system

    DEFF Research Database (Denmark)

    Kamp, Andreas; Østergård, Hanne; Hauggaard-Nielsen, Henrik

    2016-01-01

    Historically, productivity gains have been possible by the application of energy intensive technologies. In the future, new technologies and practices based on energy from renewable resources are central for the development of our food supply system and they will contribute in two different ways....... As the energy sector increasingly bases energy supply on renewable sources, the energy requirements of the food sector will automatically substitute renewable energy for non-renewable energy in all stages of food supply. In principle, the food sector does not need to change if renewable energy is sufficient...... and available as the energy carriers that we are used to today. We may think of this as passive adaptation. A passive adaptation strategy may support a development towards the image ‘high input – high output’. The food sector, however, may also actively adapt to a future without fossil fuels and change...

  7. Modelling energy systems for developing countries

    International Nuclear Information System (INIS)

    Urban, F.; Benders, R.M.J.; Moll, H.C.

    2007-01-01

    Developing countries' energy use is rapidly increasing, which affects global climate change and global and regional energy settings. Energy models are helpful for exploring the future of developing and industrialised countries. However, energy systems of developing countries differ from those of industrialised countries, which has consequences for energy modelling. New requirements need to be met by present-day energy models to adequately explore the future of developing countries' energy systems. This paper aims to assess if the main characteristics of developing countries are adequately incorporated in present-day energy models. We first discuss these main characteristics, focusing particularly on developing Asia, and then present a model comparison of 12 selected energy models to test their suitability for developing countries. We conclude that many models are biased towards industrialised countries, neglecting main characteristics of developing countries, e.g. the informal economy, supply shortages, poor performance of the power sector, structural economic change, electrification, traditional bio-fuels, urban-rural divide. To more adequately address the energy systems of developing countries, energy models have to be adjusted and new models have to be built. We therefore indicate how to improve energy models for increasing their suitability for developing countries and give advice on modelling techniques and data requirements

  8. Sustainable automotive energy system in China

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiliang (ed.) [Tsinghua Univ. Beijing (China). China Automotive Energy Research Center

    2013-06-01

    The latest research available on automotive energy system analysis in China. Thorough introduction on automotive energy system in China. Provides the broad perspective to aid in planning sustainable road transport in China. Sustainable Automotive Energy System in China aims at identifying and addressing the key issues of automotive energy in China in a systematic way, covering demography, economics, technology and policy, based on systematic and in-depth, multidisciplinary and comprehensive studies. Five scenarios of China's automotive energy development are created to analyze the possible contributions in the fields of automotive energy, vehicle fuel economy improvement, electric vehicles, fuel cell vehicles and the 2nd generation biofuel development. Thanks to this book, readers can gain a better understanding of the nature of China's automotive energy development and be informed about: (1) the current status of automotive energy consumption, vehicle technology development, automotive energy technology development and policy; (2) the future of automotive energy development, fuel consumption, propulsion technology penetration and automotive energy technology development, and (3) the pathways of sustainable automotive energy transformation in China, in particular, the technological and the policy-related options. This book is intended for researchers, engineers and graduates students in the low-carbon transportation and environmental protection field.

  9. Monitoring systems and energy management

    International Nuclear Information System (INIS)

    Roldan Oliva, J. J.

    2011-01-01

    The current situation in the general economic framework as well as the environmental context that surrounds us, has meant that increasingly more companies and institutions concerned with the control and expenditure of resources used. Among these, as an element common to any industry, building or installation, are energy resources, respondents more strongly every year. (Author)

  10. Simultaneous fMRI-PET of the opioidergic pain system in human brain

    DEFF Research Database (Denmark)

    Wey, Hsiao-Ying; Catana, Ciprian; Hooker, Jacob M

    2014-01-01

    distinct components of the blood oxygenation level dependent (BOLD) fMRI signal has not yet been shown. We obtained sixteen fMRI-PET data sets from eight healthy volunteers. Each subject participated in randomized order in a pain scan and a control (nonpainful pressure) scan on the same day. Dynamic PET......MRI and PET provide complementary information for studying brain function. While the potential use of simultaneous MRI/PET for clinical diagnostic and disease staging has been demonstrated recently; the biological relevance of concurrent functional MRI-PET brain imaging to dissect neurochemically...... data were acquired with an opioid radioligand, [(11)C]diprenorphine, to detect endogenous opioid releases in response to pain. BOLD fMRI data were collected at the same time to capture hemodynamic responses. In this simultaneous human fMRI-PET imaging study, we show co-localized responses in thalamus...

  11. A computer-aided detection system for rheumatoid arthritis MRI data interpretation and quantification of synovial activity

    DEFF Research Database (Denmark)

    Kubassove, Olga; Boesen, Mikael; Cimmino, Marco A

    2009-01-01

    and interpretation slow down development in this area. Existing scoring systems of especially synovitis are too rigid and insensitive to measure early treatment response and quantify inflammation. This study tested a novel automated, computer system for analysis of dynamic MRI data acquired from patients with RA...

  12. Thermal energy systems design and analysis

    CERN Document Server

    Penoncello, Steven G

    2015-01-01

    IntroductionThermal Energy Systems Design and AnalysisSoftwareThermal Energy System TopicsUnits and Unit SystemsThermophysical PropertiesEngineering DesignEngineering EconomicsIntroductionCommon Engineering Economics NomenclatureEconomic Analysis Tool: The Cash Flow DiagramTime Value of MoneyTime Value of Money ExamplesUsing Software to Calculate Interest FactorsEconomic Decision MakingDepreciation and TaxesProblemsAnalysis of Thermal Energy SystemsIntroductionNomenclatureThermophysical Properties of SubstancesSuggested Thermal Energy Systems Analysis ProcedureConserved and Balanced QuantitiesConservation of MassConservation of Energy (The First Law of Thermodynamics)Entropy Balance (The Second Law of Thermodynamics)Exergy Balance: The Combined LawEnergy and Exergy Analysis of Thermal Energy CyclesDetailed Analysis of Thermal Energy CyclesProblemsFluid Transport in Thermal Energy SystemsIntroductionPiping and Tubing StandardsFluid Flow FundamentalsValves and FittingsDesign and Analysis of Pipe NetworksEconomi...

  13. Energy Production System Management - Renewable energy power supply integration with Building Automation System

    International Nuclear Information System (INIS)

    Figueiredo, Joao; Martins, Joao

    2010-01-01

    Intelligent buildings, historically and technologically, refers to the integration of four distinctive systems: Building Automation Systems (BAS), Telecommunication Systems, Office Automation Systems and Computer Building Management Systems. The increasing sophisticated BAS has become the 'heart and soul' of modern intelligent buildings. Integrating energy supply and demand elements - often known as Demand-Side Management (DSM) - has became an important energy efficiency policy concept. Nowadays, European countries have diversified their power supplies, reducing the dependence on OPEC, and developing a broader mix of energy sources maximizing the use of renewable energy domestic sources. In this way it makes sense to include a fifth system into the intelligent building group: Energy Production System Management (EPSM). This paper presents a Building Automation System where the Demand-Side Management is fully integrated with the building's Energy Production System, which incorporates a complete set of renewable energy production and storage systems.

  14. Quantitative MRI study of progressive cerebral atrophy in multiple system atrophy

    International Nuclear Information System (INIS)

    Konagaya, Masaaki; Matsuoka, Yukihiko; Konagaya, Yoko

    2002-01-01

    We investigated cerebral atrophy in multiple system atrophy (MSA) by quantitative analysis of MRI. The subjects were 28 patients with MSA (14 striato-nigral degeneration; SND, 14 olivo-ponto-cerebellar atrophy; OPCA. 106 MRI examinations were performed totally) and 85 normal persons for control. The ratios of the ventral pons to the infratentorial space in the sagittal section, the putamen, cerebrum, frontal lobe and parietal and occipital lobes to the intracranial space in the horizontal section, and the temporal lobe to the intracranial space in the coronal section were measured. In the early stage of the disease, OPCA showed significant atrophy of the ventral pons compared with SND, and conversely, SND demonstrated significantly smaller putamen than that in OPCA. According to the progression of the disease, the atrophy of these neural tissues progressed, which resulted in so significant differences between SND and OPCA. The cerebral atrophy was observed in 17 MSA patients. The atrophy of the frontal lobe was much frequent and prominent to that in the temporal lobe and parietal and occipital lobes. SND showed higher incidence of the cerebral atrophy than OPCA in the early stage of the disease. In long period follow-up cases, one case showed cerebral atrophy in earlier stage, and another case in late stage. We indicated the involvement of the cerebral hemispheres in MSA, especially the frontal lobe. (author)

  15. Quantitative MRI study of progressive cerebral atrophy in multiple system atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Konagaya, Masaaki; Matsuoka, Yukihiko [Suzuka National Hospital, Suzuka, Mie (Japan); Konagaya, Yoko [JR Tokai General Hospital, Nagoya (Japan)

    2002-02-01

    We investigated cerebral atrophy in multiple system atrophy (MSA) by quantitative analysis of MRI. The subjects were 28 patients with MSA (14 striato-nigral degeneration; SND, 14 olivo-ponto-cerebellar atrophy; OPCA. 106 MRI examinations were performed totally) and 85 normal persons for control. The ratios of the ventral pons to the infratentorial space in the sagittal section, the putamen, cerebrum, frontal lobe and parietal and occipital lobes to the intracranial space in the horizontal section, and the temporal lobe to the intracranial space in the coronal section were measured. In the early stage of the disease, OPCA showed significant atrophy of the ventral pons compared with SND, and conversely, SND demonstrated significantly smaller putamen than that in OPCA. According to the progression of the disease, the atrophy of these neural tissues progressed, which resulted in so significant differences between SND and OPCA. The cerebral atrophy was observed in 17 MSA patients. The atrophy of the frontal lobe was much frequent and prominent to that in the temporal lobe and parietal and occipital lobes. SND showed higher incidence of the cerebral atrophy than OPCA in the early stage of the disease. In long period follow-up cases, one case showed cerebral atrophy in earlier stage, and another case in late stage. We indicated the involvement of the cerebral hemispheres in MSA, especially the frontal lobe. (author)

  16. Characteristic MRI findings in multiple system atrophy: comparison of the three subtypes

    Energy Technology Data Exchange (ETDEWEB)

    Naka, H.; Ohshita, T.; Murata, Y.; Imon, Y.; Mimori, Y.; Nakamura, S. [Department of Internal Medicine, Hiroshima University School of Medicine, Hiroshima (Japan)

    2002-03-01

    We reviewed MRI findings in 29 patients with probable multiple system atrophy (MSA) to see whether there were common and or less common neuroradiological findings in the various clinical subtypes. We divided the patients into three clinical subtypes according to initial and predominant symptoms: 14 with olivopontocerebellar atrophy (OPCA), eight with the Shy-Drager syndrome (SDS) and seven with striatonigral degeneration (SND). The patients showed atrophy of the brain stem and cerebellum, high signal on T2-weighted images of the base of the pons and middle cerebellar peduncles, high and low signal on T2-weighted images of the putamen and atrophy of frontal and parietal lobes. The degree of atrophy of the middle cerebellar peduncle and cerebellum was greater in OPCA patients and a high-signal lateral rim to the putamen more frequent in SND. However, all findings were observed in all subtypes, and the degrees of atrophy of the putamen and pons and the frequency of high signal in the base of the pons were similar in the subtypes. We also found atrophy of the cerebral hemispheres, especially the frontal and parietal lobes, but its degree was not significantly different in the various subtypes. Our findings suggest that, although MSA can be divided clinically into three subtypes, most of the features on MRI are common and overlap in the subtypes, independently of the clinical presentation. (orig.)

  17. The development of an MRI lesion quantifying system for multiple sclerosis patients undergoing treatment

    Science.gov (United States)

    Moin, Paymann; Ma, Kevin; Amezcua, Lilyana; Gertych, Arkadiusz; Liu, Brent

    2009-02-01

    Multiple sclerosis (MS) is a demyelinating disease of the central nervous system that affects approximately 2.5 million people worldwide. Magnetic resonance imaging (MRI) is an established tool for the assessment of disease activity, progression and response to treatment. The progression of the disease is variable and requires routine follow-up imaging studies. Currently, MRI quantification of multiple sclerosis requires a manual approach to lesion measurement and yields an estimate of lesion volume and interval change. In the setting of several prior studies and a long treatment history, trends related to treatment change quickly become difficult to extrapolate. Our efforts seek to develop an imaging informatics based MS lesion computer aided detection (CAD) package to quantify and track MS lesions including lesion load, volume, and location. Together, with select clinical parameters, this data will be incorporated into an MS specific e- Folder to provide decision support to evaluate and assess treatment options for MS in a manner tailored specifically to an individual based on trends in MS presentation and progression.

  18. Self-consistent nuclear energy systems

    International Nuclear Information System (INIS)

    Shimizu, A.; Fujiie, Y.

    1995-01-01

    A concept of self-consistent energy systems (SCNES) has been proposed as an ultimate goal of the nuclear energy system in the coming centuries. SCNES should realize a stable and unlimited energy supply without endangering the human race and the global environment. It is defined as a system that realizes at least the following four objectives simultaneously: (a) energy generation -attain high efficiency in the utilization of fission energy; (b) fuel production - secure inexhaustible energy source: breeding of fissile material with the breeding ratio greater than one and complete burning of transuranium through recycling; (c) burning of radionuclides - zero release of radionuclides from the system: complete burning of transuranium and elimination of radioactive fission products by neutron capture reactions through recycling; (d) system safety - achieve system safety both for the public and experts: eliminate criticality-related safety issues by using natural laws and simple logic. This paper describes the concept of SCNES and discusses the feasibility of the system. Both ''neutron balance'' and ''energbalance'' of the system are introduced as the necessary conditions to be satisfied at least by SCNES. Evaluations made so far indicate that both the neutron balance and the energy balance can be realized by fast reactors but not by thermal reactors. Concerning the system safety, two safety concepts: ''self controllability'' and ''self-terminability'' are introduced to eliminate the criticality-related safety issues in fast reactors. (author)

  19. A hybrid energy efficient building ventilation system

    International Nuclear Information System (INIS)

    Calay, Rajnish Kaur; Wang, Wen Chung

    2013-01-01

    The present paper presents a high performance cooling/heating ventilation system using a rotary heat exchanger (RHE), together with a reverse-cycle heat pump (RCHP) that can be integrated with various heat sources. Energy consumption in the building sector is largely dominated by the energy consumed in maintaining comfortable conditions indoors. For example in many developed countries the building heating, ventilation and air conditioning (HVAC) systems consume up to 50% of the total energy consumed in buildings. Therefore energy efficient HVAC solutions in buildings are critical for realising CO 2 targets at local and global level. There are many heating/cooling concepts that rely upon renewable energy sources and/or use natural low temperature heat sources in the winter and heat sinks in the summer. In the proposed system, waste energy from the exhaust air stream is used to precondition the outdoor air before it is supplied into the building. The hybrid system provides heating in the winter and cooling in the summer without any need for additional heating or cooling devices as required in conventional systems. Its performance is better than a typical reheat or air conditioning system in providing the same indoor air quality (IAQ) levels. It is shown that an energy saving up to 60% (heat energy) is achieved by using the proposed hybrid system in building ventilation applications. -- Highlights: • Hybrid ventilation system: the hybrid ventilation system uses a rotating regenerator and a reversible heat pump. • Heat recovery: heat recovery from exhaust air stream by rotary wheel type heat exchanger. • Reversible cycle heat pump (RCHP): additional heating or cooling of the supply air is provided by the RCHP. • Energy efficiency: energy savings of up to 60% using the proposed system are achievable

  20. An Automated and Intelligent Medical Decision Support System for Brain MRI Scans Classification.

    Directory of Open Access Journals (Sweden)

    Muhammad Faisal Siddiqui

    Full Text Available A wide interest has been observed in the medical health care applications that interpret neuroimaging scans by machine learning systems. This research proposes an intelligent, automatic, accurate, and robust classification technique to classify the human brain magnetic resonance image (MRI as normal or abnormal, to cater down the human error during identifying the diseases in brain MRIs. In this study, fast discrete wavelet transform (DWT, principal component analysis (PCA, and least squares support vector machine (LS-SVM are used as basic components. Firstly, fast DWT is employed to extract the salient features of brain MRI, followed by PCA, which reduces the dimensions of the features. These reduced feature vectors also shrink the memory storage consumption by 99.5%. At last, an advanced classification technique based on LS-SVM is applied to brain MR image classification using reduced features. For improving the efficiency, LS-SVM is used with non-linear radial basis function (RBF kernel. The proposed algorithm intelligently determines the optimized values of the hyper-parameters of the RBF kernel and also applied k-fold stratified cross validation to enhance the generalization of the system. The method was tested by 340 patients' benchmark datasets of T1-weighted and T2-weighted scans. From the analysis of experimental results and performance comparisons, it is observed that the proposed medical decision support system outperformed all other modern classifiers and achieves 100% accuracy rate (specificity/sensitivity 100%/100%. Furthermore, in terms of computation time, the proposed technique is significantly faster than the recent well-known methods, and it improves the efficiency by 71%, 3%, and 4% on feature extraction stage, feature reduction stage, and classification stage, respectively. These results indicate that the proposed well-trained machine learning system has the potential to make accurate predictions about brain abnormalities

  1. Energy Management of Smart Distribution Systems

    Science.gov (United States)

    Ansari, Bananeh

    Electric power distribution systems interface the end-users of electricity with the power grid. Traditional distribution systems are operated in a centralized fashion with the distribution system owner or operator being the only decision maker. The management and control architecture of distribution systems needs to gradually transform to accommodate the emerging smart grid technologies, distributed energy resources, and active electricity end-users or prosumers. The content of this document concerns with developing multi-task multi-objective energy management schemes for: 1) commercial/large residential prosumers, and 2) distribution system operator of a smart distribution system. The first part of this document describes a method of distributed energy management of multiple commercial/ large residential prosumers. These prosumers not only consume electricity, but also generate electricity using their roof-top solar photovoltaics systems. When photovoltaics generation is larger than local consumption, excess electricity will be fed into the distribution system, creating a voltage rise along the feeder. Distribution system operator cannot tolerate a significant voltage rise. ES can help the prosumers manage their electricity exchanges with the distribution system such that minimal voltage fluctuation occurs. The proposed distributed energy management scheme sizes and schedules each prosumer's ES to reduce the electricity bill and mitigate voltage rise along the feeder. The second part of this document focuses on emergency energy management and resilience assessment of a distribution system. The developed emergency energy management system uses available resources and redundancy to restore the distribution system's functionality fully or partially. The success of the restoration maneuver depends on how resilient the distribution system is. Engineering resilience terminology is used to evaluate the resilience of distribution system. The proposed emergency energy

  2. Whole-body MRI in children with Langerhans cell histiocytosis for the evaluation of the skeletal system

    International Nuclear Information System (INIS)

    Steinborn, M.; Woertler, K.; Rummeny, E.J.; Nathrath, M.; Schoeniger, M.; Hahn, H.

    2008-01-01

    Purpose: the usefulness of whole-body MRI (WB-MRI) for the detection of skeletal lesions in patients with Langerhans cell histiocytosis should be documented on the basis of case presentations. Materials and methods: in six patients with histologically proven Langerhans cell histiocytosis, 14 WB-MRI examinations were performed to evaluate the skeletal system within disease staging (6 primary, 8 follow-up examinations). The examinations were performed on a 1.5 Tesla, 32-channel whole-body scanner. The examination protocol consisted of T1-weighted and STIR sequences in coronal and sagittal orientation. For comparison, radiographs of the initial skeletal lesions and those that were additionally detected on WB-MRI were available. Results: in 4 patients no additional skeletal lesions were found on WB-MRI besides the initial lesion leading to the diagnosis of unifocal single system disease. In 2 patients WB-MRI was able to identify additional skeletal lesions. In a 5 1/2 year-old boy with the primary lesion located in the cervical spine, a second lesion was detected in the lumbar spine on the initial scan and in the skull and proximal femur during follow-up examination. In a 12 year-old girl with a primary lesion of the thoracic spine, WB-MRI diagnosed additional lesions in the pelvic bone and the tibia. In both patients the diagnosis of multifocal skeletal involvement led to chemotherapy. During follow-up examination, the healing response under therapy could be demonstrated. Comparison with conventional imaging showed that especially lesions located in the spine or the pelvis were not detectable on radiographs even when knowing the MR results. (orig.)

  3. A computer-aided detection system for rheumatoid arthritis MRI data interpretation and quantification of synovial activity

    DEFF Research Database (Denmark)

    Kubassove, Olga; Boesen, Mikael; Cimmino, Marco A

    2009-01-01

    RATIONAL AND OBJECTIVE: Disease assessment and follow-up of rheumatoid arthritis (RA) patients require objective evaluation and quantification. Magnetic resonance imaging (MRI) has a large potential to supplement such information for the clinician, however, time spent on data reading...... and interpretation slow down development in this area. Existing scoring systems of especially synovitis are too rigid and insensitive to measure early treatment response and quantify inflammation. This study tested a novel automated, computer system for analysis of dynamic MRI data acquired from patients with RA......, Dynamika-RA, which incorporates efficient data processing and analysis techniques....

  4. Osteitis: a retrospective feasibility study comparing single-source dual-energy CT to MRI in selected patients with suspected acute gout

    Energy Technology Data Exchange (ETDEWEB)

    Diekhoff, Torsten [Humboldt-Universitaet zu Berlin, Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Berlin (Germany); Charite - Universitaetsmedizin Berlin, Department of Radiology (CCM), Berlin (Germany); Scheel, Michael; Hamm, Bernd; Hermann, Kay-Geert A. [Humboldt-Universitaet zu Berlin, Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Berlin (Germany); Hermann, Sandra [Charite - Universitaetsmedizin Berlin Campus Mitte, Department of Rheumatology and Clinical Immunology, Berlin (Germany); Mews, Juergen [Toshiba Medical Systems Europe, BV, Zoetermeer (Netherlands)

    2017-02-15

    Dual-energy computed tomography detects tophi in patients with chronic gout. However, other information that can be obtained from the same scan is not the focus of the current research, e.g., the detection of bone marrow edema (BME) using virtual bone marrow imaging (VBMI). The aim of this study was to evaluate if BME in patients with acute arthritis can be detected with VBMI using magnetic resonance imaging (MRI) as the standard of reference. This retrospective study included 11 patients who underwent both MRI and dual-energy computed tomography (mean interval of 40 days). BME in MRI (standard of reference) and VBMI was judged independently by two different blinded readers. φ-correlation coefficient and Cohen's κ were performed for statistical analysis. Approval was waived by the IRB. Two patients with a final diagnosis of RA and one with septic arthritis showed osteitis on MRI and VBMI. However, in each case, there were individual bones identified with osteitis on MRI but not VBMI. Three additional patients with the final diagnosis of RA were identified correctly as negative for BME. There was a good correlation between both modalities (φ = 0.8; κ = 0.8). Inter-rater reliability was excellent for both modalities (κ = 0.9). We have shown that detecting osteitis using VBMI is feasible in patients with inflammatory arthritis. Further studies are needed on larger, more-targeted populations to better define the indications, accuracy, and added value of this technique. (orig.)

  5. Osteitis: a retrospective feasibility study comparing single-source dual-energy CT to MRI in selected patients with suspected acute gout

    International Nuclear Information System (INIS)

    Diekhoff, Torsten; Scheel, Michael; Hamm, Bernd; Hermann, Kay-Geert A.; Hermann, Sandra; Mews, Juergen

    2017-01-01

    Dual-energy computed tomography detects tophi in patients with chronic gout. However, other information that can be obtained from the same scan is not the focus of the current research, e.g., the detection of bone marrow edema (BME) using virtual bone marrow imaging (VBMI). The aim of this study was to evaluate if BME in patients with acute arthritis can be detected with VBMI using magnetic resonance imaging (MRI) as the standard of reference. This retrospective study included 11 patients who underwent both MRI and dual-energy computed tomography (mean interval of 40 days). BME in MRI (standard of reference) and VBMI was judged independently by two different blinded readers. φ-correlation coefficient and Cohen's κ were performed for statistical analysis. Approval was waived by the IRB. Two patients with a final diagnosis of RA and one with septic arthritis showed osteitis on MRI and VBMI. However, in each case, there were individual bones identified with osteitis on MRI but not VBMI. Three additional patients with the final diagnosis of RA were identified correctly as negative for BME. There was a good correlation between both modalities (φ = 0.8; κ = 0.8). Inter-rater reliability was excellent for both modalities (κ = 0.9). We have shown that detecting osteitis using VBMI is feasible in patients with inflammatory arthritis. Further studies are needed on larger, more-targeted populations to better define the indications, accuracy, and added value of this technique. (orig.)

  6. International Energy Agency Ocean Energy Systems Task 10 Wave Energy Converter Modeling Verification and Validation

    DEFF Research Database (Denmark)

    Wendt, Fabian F.; Yu, Yi-Hsiang; Nielsen, Kim

    2017-01-01

    This is the first joint reference paper for the Ocean Energy Systems (OES) Task 10 Wave Energy Converter modeling verification and validation group. The group is established under the OES Energy Technology Network program under the International Energy Agency. OES was founded in 2001 and Task 10 ...

  7. Energy efficiency information systems. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    It is well known that different cultures and countries are receptive in different ways to information transfer. Modern information technology, including computers, videos, and telecommunications, can provide a very useful tool for the dissemination of information. At the same time, however, the use of new media involves many new and varied challenges. It is important therefore that the new dissemination methods are developed and utilised in the most effective way depending on the subjects distinctive character, needs and traditions. This workshop was designed to gather experts from all the CADDET member countries, to share knowledge, experiences and ideas about the use of new methods of information exchange and training in the field of energy efficiency. The workshop was divided into four plenary sessions: dissemination of information on energy efficient technologies; training technologies and effective learning; computer-based training tools on energy efficiency; databases and network resources. Two discussion groups followed the plenary sessions, to concentrate on: different aspects of information exchange; and different aspects of state-of-the-art training tools. The workshop was attended by 44 participants from 17 countries, and included 14 speakers

  8. Greener energy systems energy production technologies with minimum environmental impact

    CERN Document Server

    Jeffs, Eric

    2012-01-01

    Recent years have seen acceleration in the development of cleaner energy systems. In Europe and North America, many old coal-fired power plants will be shut down in the next few years and will likely be replaced by combined cycle plants with higher-efficiency gas turbines that can start up and load quickly. With the revival of nuclear energy, designers are creating smaller nuclear reactors of a simpler integrated design that could expand the application of clean, emission-free energy to industry. And a number of manufacturers now offer hybrid cars with an electric motor and a gasoline engine t

  9. Assessing reliability in energy supply systems

    International Nuclear Information System (INIS)

    McCarthy, Ryan W.; Ogden, Joan M.; Sperling, Daniel

    2007-01-01

    Reliability has always been a concern in the energy sector, but concerns are escalating as energy demand increases and the political stability of many energy supply regions becomes more questionable. But how does one define and measure reliability? We introduce a method to assess reliability in energy supply systems in terms of adequacy and security. It derives from reliability assessment frameworks developed for the electricity sector, which are extended to include qualitative considerations and to be applicable to new energy systems by incorporating decision-making processes based on expert opinion and multi-attribute utility theory. The method presented here is flexible and can be applied to any energy system. To illustrate its use, we apply the method to two hydrogen pathways: (1) centralized steam reforming of imported liquefied natural gas with pipeline distribution of hydrogen, and (2) on-site electrolysis of water using renewable electricity produced independently from the electricity grid

  10. A Java-based fMRI processing pipeline evaluation system for assessment of univariate general linear model and multivariate canonical variate analysis-based pipelines.

    Science.gov (United States)

    Zhang, Jing; Liang, Lichen; Anderson, Jon R; Gatewood, Lael; Rottenberg, David A; Strother, Stephen C

    2008-01-01

    As functional magnetic resonance imaging (fMRI) becomes widely used, the demands for evaluation of fMRI processing pipelines and validation of fMRI analysis results is increasing rapidly. The current NPAIRS package, an IDL-based fMRI processing pipeline evaluation framework, lacks system interoperability and the ability to evaluate general linear model (GLM)-based pipelines using prediction metrics. Thus, it can not fully evaluate fMRI analytical software modules such as FSL.FEAT and NPAIRS.GLM. In order to overcome these limitations, a Java-based fMRI processing pipeline evaluation system was developed. It integrated YALE (a machine learning environment) into Fiswidgets (a fMRI software environment) to obtain system interoperability and applied an algorithm to measure GLM prediction accuracy. The results demonstrated that the system can evaluate fMRI processing pipelines with univariate GLM and multivariate canonical variates analysis (CVA)-based models on real fMRI data based on prediction accuracy (classification accuracy) and statistical parametric image (SPI) reproducibility. In addition, a preliminary study was performed where four fMRI processing pipelines with GLM and CVA modules such as FSL.FEAT and NPAIRS.CVA were evaluated with the system. The results indicated that (1) the system can compare different fMRI processing pipelines with heterogeneous models (NPAIRS.GLM, NPAIRS.CVA and FSL.FEAT) and rank their performance by automatic performance scoring, and (2) the rank of pipeline performance is highly dependent on the preprocessing operations. These results suggest that the system will be of value for the comparison, validation, standardization and optimization of functional neuroimaging software packages and fMRI processing pipelines.

  11. Complex energy system management using optimization techniques

    Energy Technology Data Exchange (ETDEWEB)

    Bridgeman, Stuart; Hurdowar-Castro, Diana; Allen, Rick; Olason, Tryggvi; Welt, Francois

    2010-09-15

    Modern energy systems are often very complex with respect to the mix of generation sources, energy storage, transmission, and avenues to market. Historically, power was provided by government organizations to load centers, and pricing was provided in a regulatory manner. In recent years, this process has been displaced by the independent system operator (ISO). This complexity makes the operation of these systems very difficult, since the components of the system are interdependent. Consequently, computer-based large-scale simulation and optimization methods like Decision Support Systems are now being used. This paper discusses the application of a DSS to operations and planning systems.

  12. Energy sources for future. Change to a sustainable energy system

    International Nuclear Information System (INIS)

    Morris, C.

    2005-01-01

    Can Germany give up gasoline and power from coal or nuclear energy and how much does it cost? The book does away with all common misunderstandings due to renewable energy sources and describes a compatible model for a sustainable energy mixing in future. Nevertheless fossil fuels are not denounced but seen as a platform for the advanced system. The author explains first why objections to renewable energy sources base on bad information, and pursues quite an other argumentation as such authors emphasizing the potential of these energy sources. Than he shows in detail the possibility of the optimal energy mixing for biomass, solar power, wind power, geothermal energy, hydropower and energy efficiency. The environment will reward us for this and instead buying expensive resources from foreign countries we will create work places at home. The number of big power plants - taking into account safety risks - will decrease and small units of on-site power generation feeded with this renewable sources will play more and more an important role. (GL) [de

  13. Renewable energy for sustainable electrical energy system in India

    International Nuclear Information System (INIS)

    Mallah, Subhash; Bansal, N.K.

    2010-01-01

    Present trends of electrical energy supply and demand are not sustainable because of the huge gap between demand and supply in foreseeable future in India. The path towards sustainability is exploitation of energy conservation and aggressive use of renewable energy systems. Potential of renewable energy technologies that can be effectively harnessed would depend on future technology developments and breakthrough in cost reduction. This requires adequate policy guidelines and interventions in the Indian power sector. Detailed MARKAL simulations, for power sector in India, show that full exploitation of energy conservation potential and an aggressive implementation of renewable energy technologies lead to sustainable development. Coal and other fossil fuel (gas and oil) allocations stagnated after the year 2015 and remain constant up to 2040. After the year 2040, the requirement for coal and gas goes down and carbon emissions decrease steeply. By the year 2045, 25% electrical energy can be supplied by renewable energy and the CO 2 emissions can be reduced by 72% as compared to the base case scenario. (author)

  14. Policies for 100% Renewable Energy Systems

    DEFF Research Database (Denmark)

    Hvelplund, Frede

    2014-01-01

    The official Danish energy policy goal is both to increase the wind power share of electricity consumption from 33% in 2014 to 50% by 2020 and to have a 100% renewable energy based energy system by 2050. This is a huge technological change from stored, scarce and polluting fossil fuels...... to fluctuating, abundant and clean energy sources. “Stored” fossil fuels can be used when needed; fluctuating energy sources must be captured when available and transformed to meet the energy needs of society in the right amounts and at the right time. We are amidst this change. Renewable energy has come of age...... and is no longer a minor technology experimenting in the corner of the energy scene, but has become a large new technology taking away considerable market shares from the old fossil fuel technologies....

  15. Solar Energy Grid Integration Systems -- Energy Storage (SEGIS-ES).

    Energy Technology Data Exchange (ETDEWEB)

    Hanley, Charles J.; Ton, Dan T. (U.S. Department of Energy, Washington, D.C.); Boyes, John D.; Peek, Georgianne Huff

    2008-07-01

    This paper describes the concept for augmenting the SEGIS Program (an industry-led effort to greatly enhance the utility of distributed PV systems) with energy storage in residential and small commercial applications (SEGIS-ES). The goal of SEGIS-ES is to develop electrical energy storage components and systems specifically designed and optimized for grid-tied PV applications. This report describes the scope of the proposed SEGIS-ES Program and why it will be necessary to integrate energy storage with PV systems as PV-generated energy becomes more prevalent on the nation's utility grid. It also discusses the applications for which energy storage is most suited and for which it will provide the greatest economic and operational benefits to customers and utilities. Included is a detailed summary of the various storage technologies available, comparisons of their relative costs and development status, and a summary of key R&D needs for PV-storage systems. The report concludes with highlights of areas where further PV-specific R&D is needed and offers recommendations about how to proceed with their development.

  16. An Empirical Model for Energy Storage Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rosewater, David Martin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Scott, Paul [TransPower, Poway, CA (United States)

    2016-03-17

    Improved models of energy storage systems are needed to enable the electric grid’s adaptation to increasing penetration of renewables. This paper develops a generic empirical model of energy storage system performance agnostic of type, chemistry, design or scale. Parameters for this model are calculated using test procedures adapted from the US DOE Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage. We then assess the accuracy of this model for predicting the performance of the TransPower GridSaver – a 1 MW rated lithium-ion battery system that underwent laboratory experimentation and analysis. The developed model predicts a range of energy storage system performance based on the uncertainty of estimated model parameters. Finally, this model can be used to better understand the integration and coordination of energy storage on the electric grid.

  17. Energy Flexibility in the Power System

    DEFF Research Database (Denmark)

    Billanes, Joy Dalmacio; Ma, Zheng; Jørgensen, Bo Nørregaard

    2017-01-01

    Energy flexibility can address the challenges of large scale integration of renewable energy resources and thereby increasing imbalance in the power system. Flexible power system can provide reliable supply, low electricity cost and sustainability. Various situations and factors influence...... the adoption of the flexibility solutions, such as flexible electricity generation, demand-response, and electricity storage. This paper tries to analyze the current energy flexibility solutions and the factors that can influence the energy flexibility adoption. This paper takes Philippines as case study...... to provide an overview of the current condition of the Philippines’ power system and discuss the energy flexibility in the Philippines’ power system. A further discussion and recommendation is conducted in the end of the paper....

  18. Energy innovation systems indicator report 2012

    Energy Technology Data Exchange (ETDEWEB)

    Borup, M. [Technical Univ. of Denmark. DTU Management Engineering, Kgs. Lyngby (Denmark); Klitkou, A.; Iversen, E. [Nordic Institute for Studies in Innovation, Research and Education, Oslo (Norway)

    2012-12-15

    Knowledge about the innovation systems with respect to new energy solutions and technologies is of central importance for understanding the dynamics of change in the energy sector and assessment of opportunities for moving towards more climate-friendly and sustainable energy systems and for socio-economic development in the field, creation of new businesses, work places, etc.. This is the topic that in general is addressed in the research activities of the ''EIS - Strategic research alliance for Energy Innovation Systems and their dynamics - Denmark in global competition''. As part of this, the present report gives an overview of the available indicators of energy innovation systems and points out some of the limitations and potentials there currently are in this connection. Focus is on Denmark. Figures for other countries, primarily Nordic or European, are in some cases showed as well, offering a comparative perspective. (Author)

  19. Energy-efficient fault-tolerant systems

    CERN Document Server

    Mathew, Jimson; Pradhan, Dhiraj K

    2013-01-01

    This book describes the state-of-the-art in energy efficient, fault-tolerant embedded systems. It covers the entire product lifecycle of electronic systems design, analysis and testing and includes discussion of both circuit and system-level approaches. Readers will be enabled to meet the conflicting design objectives of energy efficiency and fault-tolerance for reliability, given the up-to-date techniques presented.

  20. Energy Innovation Systems Indicator Report 2012

    DEFF Research Database (Denmark)

    Klitkou, Antje; Borup, Mads; Iversen, Eric

    This report is the first report in a series of reports on energy innovation system indicators produced as part of the activities in the “EIS Strategic research alliance for Energy Innovation Systems and their dynamics – Denmark in global competition”. The work is based on a number of existing......). The report received also valuable input from a project commissioned by IPTS. This project addressed co-operation patterns and knowledge flows in patent documents in the fields of wind energy, photovoltaic energy and concentrating solar power (Iversen and Patel, 2010). The results relevant for this project...

  1. Environmental health risk assessment: Energy systems

    International Nuclear Information System (INIS)

    Krewski, D.; Somers, E.; Winthrop, S.O.

    1984-01-01

    Most industrialized nations have come to rely on a variety of systems for energy production, both of a conventional and non-conventional nature. In the paper, the spectrum of energy systems currently in use in Canada is outlined along with their potential health risks. Several examples of environmental health studies involving both outdoor and indoor air pollution related to energy production in Canada are reported. The limitations of current technologies for assessing health risks are discussed and possible approaches to managing energy related health risks are indicated. (author)

  2. Kinetic Storage as an Energy Management System

    International Nuclear Information System (INIS)

    Garcia-Tabares, L.

    2007-01-01

    The possibility of storing energy is increasingly important and necessary. The reason is that storage modifies the basic equation of the energy production balance which states that the power produced should equal the power consumed. When there is a storage device in the grid, this equation is modified such that, in the new balance, the energy produced should equal the algebraic sum of the energy consumed and the energy stored (positive in storage phase and negative when released). This means that the generation profile can be uncoupled from the consumption profile, with the resulting improvement of efficiency. Even small-sized storage systems can be very effective. (Author) 10 refs

  3. Photovoltaic energy systems. Program summary

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-01-01

    The ongoing research, development, and demonstration efforts of the Photovoltaics Program are highlighted and each of the US Department of Energy's current photovoltaics projects initiated or renewed during fiscal year 1981 is described, including its title, directing organization, project engineer, contractor, principal investigator, contract period, funding, and objectives. The Photovoltaics Program is briefly summarized, including the history and organization and highlights of the research and development and of planning, assessment, and integration. Also summarized is the Federal Photovoltaic Utilization Program. An exhaustive bibliography is included. (LEW)

  4. Energy efficient residential house wall system

    International Nuclear Information System (INIS)

    Aldawi, Fayez; Date, Abhijit; Alam, Firoz; Khan, Iftekhar; Alghamdi, Mohammed

    2013-01-01

    The energy consumption and greenhouse gas emission by the residential housing sector are considered to be one of the largest in economically developed countries. The larger energy consumption and greenhouse gas emission not only put additional pressure on finite fossil fuel resources but also cause global warming and climate change. Additionally, the residential housing sector will be consuming more energy as the house demand and average house floor area are progressively increasing. With currently used residential house wall systems, it is hard to reduce energy consumption for ongoing house space heating and cooling. A smart house wall envelope with optimal thermal masses and insulation materials is vital for reducing our increasing energy consumption. The major aim of this study is to investigate thermal performance and energy saving potential of a new house wall system for variable climate conditions. The thermal performance modelling was carried out using commercially developed software AccuRate ® . The findings indicate that a notable energy savings can be accomplished if a smart house wall system is used. -- Highlights: • Smart house wall system. • Thermal performance modelling and star energy rating. • Energy savings and greenhouse gas reduction

  5. Contrast-Enhanced Spectral Mammography is Comparable to MRI in the Assessment of Residual Breast Cancer Following Neoadjuvant Systemic Therapy.

    Science.gov (United States)

    Patel, Bhavika K; Hilal, Talal; Covington, Matthew; Zhang, Nan; Kosiorek, Heidi E; Lobbes, Marc; Northfelt, Donald W; Pockaj, Barbara A

    2018-05-01

    To evaluate the performance of contrast-enhanced spectral mammography (CESM) compared to MRI in the assessment of tumor response in breast cancer patients undergoing neoadjuvant systemic therapy (NST). The institutional review board approved this study. From September 2014 to June 2017, we identified patients with pathologically confirmed invasive breast cancer who underwent NST. All patients had both CESM and MRI performed pre- and post-NST with pathological assessment after surgical management. Size of residual malignancy on post-NST CESM and MRI was compared with surgical pathology. Lin concordance and Pearson correlation coefficient were used to assess agreement. Bland-Altman plots were used to visualize the differences between tumor size on imaging and pathology. Sixty-five patients were identified. Mean age was 52.7 (range 30-76) years. Type of NST included chemotherapy in 53 (82%) and endocrine therapy in 12 (18%). Mean tumor size after NST was 14.6 (range 0-105) mm for CESM and 14.2 mm (range 0-75 mm) for MRI compared with 19.6 (range 0-100) mm on final surgical pathology. Equivalence tests demonstrated that mean tumor size measured by CESM (p = 0.009) or by MRI (p = 0.01) was equivalent to the mean tumor size measured by pathology within - 1 and 1-cm range. Comparing CESM versus MRI for assessment of complete response, the sensitivity was 95% versus 95%, specificity 66.7% versus 68.9%, positive predictive value 55.9% versus 57.6%, and negative predictive value 96.7% versus 96.9% respectively. CESM was comparable to MRI in assessing residual malignancy after completion of NST.

  6. Efficiency of unenhanced MRI in the diagnosis of acute appendicitis: Comparison with Alvarado scoring system and histopathological results

    International Nuclear Information System (INIS)

    Inci, Ercan; Hocaoglu, Elif; Aydin, Sibel; Palabiyik, Figen; Cimilli, Tan; Turhan, Ahmet Nuray; Ayguen, Ersan

    2011-01-01

    Purpose: The purpose of this study was to assess the diagnostic value of unenhanced magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis and compare with Alvarado scores and histopathological results. Materials and methods: The study included 85 consecutive patients (mean age, 26.5 ± 11.3 years) who were clinically suspected of having acute appendicitis. Each patients Alvarado scores were recorded and unenhanced MRI was performed, consisting of T1-weighted, T2-weighted and fat-suppressed T2-weighted fast spin-echo sequences. The MR images were prospectively reviewed in consensus for the presence of acute appendicitis by two radiologists who were blinded to the results of the Alvarado scores. The study population were divided into three subgroups based on the MRI findings: Group I: definitely not appendicitis, Group II: probably appendicitis, Group III: definitely appendicitis. All patients were divided into two subgroups according to Alvarado scores as Group A (low: 1-6), and Group B (high: 7-10). MR findings were compared with Alvarado scores and histopathological findings. Results: Sixty-six (77.6%) of the 85 patients with clinically suspected acute appendicitis, had undergone surgery. The diagnosis of appendicitis could be correctly achieved with MRI in 55 (83.3%) of 57 (86.4%) patients with histopathologically proven acute appendicitis. The sensitivity, specificity, positive predictive value and negative predictive value of MRI examination and Alvarado scoring system in the diagnosis of acute appendicitis were 96.49%, 66.67%, 94.83%, 75.0% and 84.21%, 66.67%, 94.12%, 40.0%, respectively. Conclusions: MRI is a valuable technique for detecting acute appendicitis even in the cases with low Alvarado scores. To increase the diagnostic accuracy and preventing unnecessary laparotomies for suspected appendicitis, shorter and cheaper unenhanced basic MRI may be performed.

  7. Efficiency of unenhanced MRI in the diagnosis of acute appendicitis: Comparison with Alvarado scoring system and histopathological results

    Energy Technology Data Exchange (ETDEWEB)

    Inci, Ercan, E-mail: ercan_inci@mynet.com [Department of Radiology, Istanbul Bakirkoy Dr. Sadi Konuk Training and Research Hospital, Incirli-Bakirkoy, Istanbul (Turkey); Hocaoglu, Elif; Aydin, Sibel; Palabiyik, Figen; Cimilli, Tan [Department of Radiology, Istanbul Bakirkoy Dr. Sadi Konuk Training and Research Hospital, Incirli-Bakirkoy, Istanbul (Turkey); Turhan, Ahmet Nuray; Ayguen, Ersan [Department of Surgery, Istanbul Bakirkoy Dr. Sadi Konuk Training and Research Hospital, Istanbul (Turkey)

    2011-11-15

    Purpose: The purpose of this study was to assess the diagnostic value of unenhanced magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis and compare with Alvarado scores and histopathological results. Materials and methods: The study included 85 consecutive patients (mean age, 26.5 {+-} 11.3 years) who were clinically suspected of having acute appendicitis. Each patients Alvarado scores were recorded and unenhanced MRI was performed, consisting of T1-weighted, T2-weighted and fat-suppressed T2-weighted fast spin-echo sequences. The MR images were prospectively reviewed in consensus for the presence of acute appendicitis by two radiologists who were blinded to the results of the Alvarado scores. The study population were divided into three subgroups based on the MRI findings: Group I: definitely not appendicitis, Group II: probably appendicitis, Group III: definitely appendicitis. All patients were divided into two subgroups according to Alvarado scores as Group A (low: 1-6), and Group B (high: 7-10). MR findings were compared with Alvarado scores and histopathological findings. Results: Sixty-six (77.6%) of the 85 patients with clinically suspected acute appendicitis, had undergone surgery. The diagnosis of appendicitis could be correctly achieved with MRI in 55 (83.3%) of 57 (86.4%) patients with histopathologically proven acute appendicitis. The sensitivity, specificity, positive predictive value and negative predictive value of MRI examination and Alvarado scoring system in the diagnosis of acute appendicitis were 96.49%, 66.67%, 94.83%, 75.0% and 84.21%, 66.67%, 94.12%, 40.0%, respectively. Conclusions: MRI is a valuable technique for detecting acute appendicitis even in the cases with low Alvarado scores. To increase the diagnostic accuracy and preventing unnecessary laparotomies for suspected appendicitis, shorter and cheaper unenhanced basic MRI may be performed.

  8. A medical software system for volumetric analysis of cerebral pathologies in magnetic resonance imaging (MRI) data.

    Science.gov (United States)

    Egger, Jan; Kappus, Christoph; Freisleben, Bernd; Nimsky, Christopher

    2012-08-01

    In this contribution, a medical software system for volumetric analysis of different cerebral pathologies in magnetic resonance imaging (MRI) data is presented. The software system is based on a semi-automatic segmentation algorithm and helps to overcome the time-consuming process of volume determination during monitoring of a patient. After imaging, the parameter settings-including a seed point-are set up in the system and an automatic segmentation is performed by a novel graph-based approach. Manually reviewing the result leads to reseeding, adding seed points or an automatic surface mesh generation. The mesh is saved for monitoring the patient and for comparisons with follow-up scans. Based on the mesh, the system performs a voxelization and volume calculation, which leads to diagnosis and therefore further treatment decisions. The overall system has been tested with different cerebral pathologies-glioblastoma multiforme, pituitary adenomas and cerebral aneurysms- and evaluated against manual expert segmentations using the Dice Similarity Coefficient (DSC). Additionally, intra-physician segmentations have been performed to provide a quality measure for the presented system.

  9. Energy efficiency of milkmaid systems in Uruguay

    International Nuclear Information System (INIS)

    LLanos, E.; Astigarraga, L.; Jacques, R.; Picasso, V.

    2013-01-01

    Reducing fossil fuel consumption and increasing energy efficiency of agricultural systems may result in environmental and economic benefits. The aim of this study was to analyze dairy production systems from an energy perspective, to identify the main variables affecting energy efficiency and fossil energy consumption, through a model of inputs and outputs. The model included as inputs energy costs of food, labor, electricity, agrochemicals, fuels and machinery, and as outputs dairy and meat production. We analyzed a database of 30 dairy farms from southern Uruguay, from the Cooperative Nacional de Product ores de Leche (Conaprole), organized in three strata based on their dairy productivity per hectare. The fossil energy use was 2.40, 3.63 y 3.80 MJ.l-1 for productivity strata low, medium and high respectively (P<0.01). Energy efficiency averages were 1.40, 0.90 y 0.86 for the same strata (P<0.01). Fossil energy of agrochemicals and fuel accounted for more than 80% of the energy consumed in the three strata. The greater the percentage of concentrate in the diet, the lower energy efficiency (P<0.01). These results suggest the existence of a negative relationship between the intensification of dairy production and energy efficiency

  10. Wind Energy Conversion Systems Technology and Trends

    CERN Document Server

    2012-01-01

    Wind Energy Conversion System covers the technological progress of wind energy conversion systems, along with potential future trends. It includes recently developed wind energy conversion systems such as multi-converter operation of variable-speed wind generators, lightning protection schemes, voltage flicker mitigation and prediction schemes for advanced control of wind generators. Modeling and control strategies of variable speed wind generators are discussed, together with the frequency converter topologies suitable for grid integration. Wind Energy Conversion System also describes offshore farm technologies including multi-terminal topology and space-based wind observation schemes, as well as both AC and DC based wind farm topologies. The stability and reliability of wind farms are discussed, and grid integration issues are examined in the context of the most recent industry guidelines. Wind power smoothing, one of the big challenges for transmission system operators, is a particular focus. Fault ride th...

  11. Energy-Aware Cognitive Radio Systems

    KAUST Repository

    Bedeer, Ebrahim

    2016-01-15

    The concept of energy-aware communications has spurred the interest of the research community in the most recent years due to various environmental and economical reasons. It becomes indispensable for wireless communication systems to shift their resource allocation problems from optimizing traditional metrics, such as throughput and latency, to an environmental-friendly energy metric. Although cognitive radio systems introduce spectrum efficient usage techniques, they employ new complex technologies for spectrum sensing and sharing that consume extra energy to compensate for overhead and feedback costs. Considering an adequate energy efficiency metric—that takes into account the transmit power consumption, circuitry power, and signaling overhead—is of momentous importance such that optimal resource allocations in cognitive radio systems reduce the energy consumption. A literature survey of recent energy-efficient based resource allocations schemes is presented for cognitive radio systems. The energy efficiency performances of these schemes are analyzed and evaluated under power budget, co-channel and adjacent-channel interferences, channel estimation errors, quality-of-service, and/or fairness constraints. Finally, the opportunities and challenges of energy-aware design for cognitive radio systems are discussed.

  12. Stochastic Modelling of Energy Systems

    DEFF Research Database (Denmark)

    Andersen, Klaus Kaae

    2001-01-01

    is that the model structure has to be adequate for practical applications, such as system simulation, fault detection and diagnosis, and design of control strategies. This also reflects on the methods used for identification of the component models. The main result from this research is the identification......In this thesis dynamic models of typical components in Danish heating systems are considered. Emphasis is made on describing and evaluating mathematical methods for identification of such models, and on presentation of component models for practical applications. The thesis consists of seven...... research papers (case studies) together with a summary report. Each case study takes it's starting point in typical heating system components and both, the applied mathematical modelling methods and the application aspects, are considered. The summary report gives an introduction to the scope...

  13. Planning for rural energy system: Part 2

    International Nuclear Information System (INIS)

    Devadas, V.

    2001-01-01

    This paper discusses the central importance of energy inputs in development, and presents the complex interactions within subsystems that contribute a Rural Energy System. This paper also brings about the importance of the primary data for realistic renewable energy planning at the micro level in a given rural system. Factors that render secondary data somewhat inadequate for such applications are discussed. The differences between energy related data from secondary and primary sources in respect of representative villages in Kanyakumari District of Tamil Nadu, India, are detailed. A rural system model for computing the output from various components of a rural system is also presented. This projection is made by making use of a set of technical coefficients, which relate the inputs to the outputs from individual segments of the rural production system. While some of the technical coefficients are developed based on previously published data, a large number have been quantified on the basis of careful survey. The usefulness of the model is discussed. The paper also presents a Linear Programming Model for optimum resource allocation in a rural system. The objective function of the Linear Programming Model is maximizing the revenue of the rural system where in optimum resource allocation is made subject to a number of energy and non-energy related relevant constraints. The model also quantifies the major yields as well as the byproducts of different sectors of the rural economic system. (Author)

  14. An Optically-Coupled System for Quantitative Monitoring of MRI-Induced RF Currents into Long Conductors

    Science.gov (United States)

    Zanchi, Marta G.; Venook, Ross; Pauly, John M.; Scott, Greig C.

    2010-01-01

    The currents induced in long conductors such as guidewires by the radio frequency (RF) field in magnetic resonance imaging (MRI) are responsible for potentially dangerous heating of surrounding media, such as tissue. This paper presents an optically-coupled system with the potential to quantitatively measure the RF currents induced on these conductors. The system uses a self shielded toroid transducer and active circuitry to modulate a high speed LED transmitter. Plastic fiber guides the light to a photodiode receiver and transimpedance amplifier. System validation included a series of experiments with bare wires that compared wire tip heating by fluoroptic thermometers with the RF current sensor response. Validations were performed on a custom whole body 64 MHz birdcage test platform and on a 1.5T MRI scanner. With this system, a variety of phenomena were demonstrated including cable trap current attenuation, lossy dielectric Q-spoiling and even transverse electromagnetic wave node patterns. This system should find applications in studies of MRI RF safety for interventional devices such as pacemaker leads, and guidewires. In particular, variations of this device could potentially act as a realtime safety monitor during MRI guided interventions. PMID:19758855

  15. Miniature photovoltaic energy system for lighting

    International Nuclear Information System (INIS)

    Awais, M.

    1999-01-01

    In this project a miniature photovoltaic energy system has been designed and developed, that may be used in remote areas and villages for lighting purposes. System sizing is the important part of the project because it affects the cost of the system. Therefore, first of all system sizing has been done. For conversion of dc voltage of the battery into ac voltage, an inverter has been designed. To charge the battery when the sun is not shining, a standby system has been developed using a bicycle and dynamo. To indicate the battery's state of charge and discharge, a battery monitoring circuit has also been developed. Similarly, to protect the battery from over discharging, a battery protection circuit has been designed. In order to measure how much energy is going from standby system to the battery, an efficient dc electronic energy meter has been designed and developed. The working of the overall system has been tested and found to give good performance. (author)

  16. Seasonal energy storage - PV-hydrogen systems

    Energy Technology Data Exchange (ETDEWEB)

    Leppaenen, J. [Neste Oy/NAPS (Finland)

    1998-10-01

    PV systems are widely used in remote areas e.g. in telecommunication systems. Typically lead acid batteries are used as energy storage. In northern locations seasonal storage is needed, which however is too expensive and difficult to realise with batteries. Therefore, a PV- battery system with a diesel backup is sometimes used. The disadvantages of this kind of system for very remote applications are the need of maintenance and the need to supply the fuel. To overcome these problems, it has been suggested to use hydrogen technologies to make a closed loop autonomous energy storage system

  17. Design and installation of earth energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Loggia, S; Adragna, M; Coyle, S; Foley, C; Hawryn, S; Martin, A; McConnell, J [eds.

    2002-07-01

    This first edition of the Canadian Standards Association (CSA) Standard C448 Series, replaces CSA Standards CAN/CSA-C445-M92 entitled Design and Installation of Earth Energy Heat Pump Systems for Residential and Other Small Buildings, as well as C447-94 entitled Design and Installation of Earth Energy Heat Pump Systems for Commercial and Institutional Buildings. This standard document consists of three parts: (C448.1) Design and installation of earth energy systems for commercial and institutional buildings; (C448.2) Design and installation of earth energy systems for residential and small buildings; and, (C448.3) Design and installation of underground thermal energy storage systems for commercial and institutional buildings. In C448.1, the requirements applicable to any system falling within the scope of the C448 series were included. Alternative requirements for houses and small buildings were added in C448.2. It was noted that either standard may be implemented. The standards applicable to the intentional storage of energy in the earth for later use were presented in C448.3. This latter section includes a brief introduction on underground thermal energy storage (UTES). tabs.

  18. A multimodal MRI approach to identify and characterize microstructural brain changes in neuropsychiatric systemic lupus erythematosus.

    Science.gov (United States)

    Ercan, Ece; Ingo, Carson; Tritanon, Oranan; Magro-Checa, Cesar; Smith, Alex; Smith, Seth; Huizinga, Tom; van Buchem, Mark A; Ronen, Itamar

    2015-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disease with multi-organ involvement and results in neurological and psychiatric (NP) symptoms in up to 40% of the patients. To date, the diagnosis of neuropsychiatric systemic lupus erythematosus (NPSLE) poses a challenge due to the lack of neuroradiological gold standards. In this study, we aimed to better localize and characterize normal appearing white matter (NAWM) changes in NPSLE by combining data from two quantitative MRI techniques, diffusion tensor imaging (DTI) and magnetization transfer imaging (MTI). 9 active NPSLE patients (37 ± 13 years, all females), 9 SLE patients without NP symptoms (44 ± 11 years, all females), and 14 healthy controls (HC) (40 ± 9 years, all females) were included in the study. MTI, DTI and fluid attenuated inversion recovery (FLAIR) images were collected from all subjects on a 3 T MRI scanner. Magnetization transfer ratio (MTR), mean diffusivity (MD), fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity (AD) maps and white matter lesion maps based on the FLAIR images were created for each subject. MTR and DTI data were then co-analyzed using tract-based spatial statistics and a cumulative lesion map to exclude lesions. Significantly lower MTR and FA and significantly higher AD, RD and MD were found in NPSLE compared to HC in NAWM regions. The differences in DTI measures and in MTR, however, were only moderately co-localized. Additionally, significant differences in DTI measures, but not in MTR, were found between NPSLE and SLE patients, suggesting that the underlying microstructural changes detected by MD are linked to the onset of NPSLE. The co-analysis of the anatomical distribution of MTI and DTI measures can potentially improve the diagnosis of NPSLE and contribute to the understanding of the underlying microstructural damage.

  19. Army Energy and Water Reporting System Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Deprez, Peggy C.; Giardinelli, Michael J.; Burke, John S.; Connell, Linda M.

    2011-09-01

    There are many areas of desired improvement for the Army Energy and Water Reporting System. The purpose of system is to serve as a data repository for collecting information from energy managers, which is then compiled into an annual energy report. This document summarizes reported shortcomings of the system and provides several alternative approaches for improving application usability and adding functionality. The U.S. Army has been using Army Energy and Water Reporting System (AEWRS) for many years to collect and compile energy data from installations for facilitating compliance with Federal and Department of Defense energy management program reporting requirements. In this analysis, staff from Pacific Northwest National Laboratory found that substantial opportunities exist to expand AEWRS functions to better assist the Army to effectively manage energy programs. Army leadership must decide if it wants to invest in expanding AEWRS capabilities as a web-based, enterprise-wide tool for improving the Army Energy and Water Management Program or simply maintaining a bottom-up reporting tool. This report looks at both improving system functionality from an operational perspective and increasing user-friendliness, but also as a tool for potential improvements to increase program effectiveness. The authors of this report recommend focusing on making the system easier for energy managers to input accurate data as the top priority for improving AEWRS. The next major focus of improvement would be improved reporting. The AEWRS user interface is dated and not user friendly, and a new system is recommended. While there are relatively minor improvements that could be made to the existing system to make it easier to use, significant improvements will be achieved with a user-friendly interface, new architecture, and a design that permits scalability and reliability. An expanded data set would naturally have need of additional requirements gathering and a focus on integrating

  20. Balmorel open source energy system model

    DEFF Research Database (Denmark)

    Wiese, Frauke; Bramstoft, Rasmus; Koduvere, Hardi

    2018-01-01

    As the world progresses towards a cleaner energy future with more variable renewable energy sources, energy system models are required to deal with new challenges. This article describes design, development and applications of the open source energy system model Balmorel, which is a result...... of a long and fruitful cooperation between public and private institutions within energy system research and analysis. The purpose of the article is to explain the modelling approach, to highlight strengths and challenges of the chosen approach, to create awareness about the possible applications...... of Balmorel as well as to inspire to new model developments and encourage new users to join the community. Some of the key strengths of the model are the flexible handling of the time and space dimensions and the combination of operation and investment optimisation. Its open source character enables diverse...

  1. MRI zoo

    DEFF Research Database (Denmark)

    Laustsen, Christoffer

    The basic idea was to use MRI to produce a sequence of 3D gray scale image slices of various animals, subsequentlyimaged with a clinical CT system. For this purpose, these animals were used: toad, lungfish, python snake and a horseshoe crab. Each animal was sacrificed according to standard...... visually inspected, both in 2D and 3D, and compared with photographs and anatomy atlases found at library and on the internet....

  2. Third degree skin burns caused by a MRI conditional electrocardiographic monitoring system

    Directory of Open Access Journals (Sweden)

    Brix L

    2016-10-01

    Full Text Available Two unusual cases of third degree skin burns are reported using MRI approved electrocardiographic leads. This is very uncommon as it is most often the electrodes which are the source of heat related issues. Both patients were sedated due to pain related issues of their lower spine. The burns were caused by a combination of using a 3 Tesla MRI scanner and the inability to cry out during scanning. We would like to bring forward a message that even when using MRI conditional equipment, clinical staff must be extremely careful in order to secure safe image acquisition using MRI.

  3. Risks of disaster in the energy system

    International Nuclear Information System (INIS)

    Kristoferson, L.; Kjellstroem, B.; Svenningsson, P.J.

    1986-10-01

    The perception of environmental effects and risks is discussed concerning the difficulties to making objective comparisons between different energy sources. Risks may influence the choice of strategies of the replacement of nuclear electric power in the Swedish energy system. Risks for major accidents and disasters to occur at a small level of probability are presented concerning the existing or future energy sources. The choice of strategies is discussed by means of calculated examples

  4. Analytical energy spectrum for hybrid mechanical systems

    International Nuclear Information System (INIS)

    Zhong, Honghua; Xie, Qiongtao; Lee, Chaohong; Guan, Xiwen; Gao, Kelin; Batchelor, Murray T

    2014-01-01

    We investigate the energy spectrum for hybrid mechanical systems described by non-parity-symmetric quantum Rabi models. A set of analytical solutions in terms of the confluent Heun functions and their analytical energy spectrum is obtained. The analytical energy spectrum includes regular and exceptional parts, which are both confirmed by direct numerical simulation. The regular part is determined by the zeros of the Wronskian for a pair of analytical solutions. The exceptional part is relevant to the isolated exact solutions and its energy eigenvalues are obtained by analyzing the truncation conditions for the confluent Heun functions. By analyzing the energy eigenvalues for exceptional points, we obtain the analytical conditions for the energy-level crossings, which correspond to two-fold energy degeneracy. (paper)

  5. Adaptive, full-spectrum solar energy system

    Science.gov (United States)

    Muhs, Jeffrey D.; Earl, Dennis D.

    2003-08-05

    An adaptive full spectrum solar energy system having at least one hybrid solar concentrator, at least one hybrid luminaire, at least one hybrid photobioreactor, and a light distribution system operably connected to each hybrid solar concentrator, each hybrid luminaire, and each hybrid photobioreactor. A lighting control system operates each component.

  6. Energy Devices and Political Consumerism in Reconfigured Energy Systems

    NARCIS (Netherlands)

    Kloppenburg, S.; Vliet, van B.J.M.

    2018-01-01

    This chapter discusses political consumerism in the context of a transformation towards a low-carbon electricity system. Over the past decades, deregulation, liberalisation, and privatisation have opened up spaces for Western consumers to influence the greening of energy provision and consumption

  7. Environmental benefits of domestic solar energy systems

    International Nuclear Information System (INIS)

    Kalogirou, Soteris A.

    2004-01-01

    All nations of the world depend on fossil fuels for their energy needs. However the obligation to reduce CO 2 and other gaseous emissions in order to be in conformity with the Kyoto agreement is the reason behind which countries turn to non-polluting renewable energy sources. In this paper the pollution caused by the burning of fossil fuels is initially presented followed by a study on the environmental protection offered by the two most widely used renewable energy systems, i.e. solar water heating and solar space heating. The results presented in this paper show that by using solar energy, considerable amounts of greenhouse polluting gasses are avoided. For the case of a domestic water heating system, the saving, compared to a conventional system, is about 80% with electricity or Diesel backup and is about 75% with both electricity and Diesel backup. In the case of space heating and hot water system the saving is about 40%. It should be noted, however, that in the latter, much greater quantities of pollutant gasses are avoided. Additionally, all systems investigated give positive and very promising financial characteristics. With respect to life cycle assessment of the systems, the energy spent for manufacture and installation of the solar systems is recouped in about 1.2 years, whereas the payback time with respect to emissions produced from the embodied energy required for the manufacture and installation of the systems varies from a few months to 9.5 years according to the fuel and the particular pollutant considered. Moreover, due to the higher solar contribution, solar water heating systems have much shorter payback times than solar space heating systems. It can, therefore, be concluded that solar energy systems offer significant protection to the environment and should be employed whenever possible in order to achieve a sustainable future

  8. Ultra-sensitive molecular MRI of cerebrovascular cell activation enables early detection of chronic central nervous system disorders

    International Nuclear Information System (INIS)

    Montagne, Axel; Gauberti, Maxime; Jullienne, Amandine; Briens, Aurelien; Docagne, Fabian; Vivien, Denis; Maubert, Eric; Macrez, Richard; Defer, Gilles; Raynaud, Jean-Sebastien; Louin, Gaelle; Buisson, Alain; Haelewyn, Benoit

    2012-01-01

    Since endothelial cells can be targeted by large contrast-carrying particles, molecular imaging of cerebrovascular cell activation is highly promising to evaluate the underlying inflammation of the central nervous system (CNS). In this study, we aimed to demonstrate that molecular magnetic resonance imaging (MRI) of cerebrovascular cell activation can reveal CNS disorders in the absence of visible lesions and symptoms. To this aim, we optimized contrast carrying particles targeting vascular cell adhesion molecule-1 and MRI protocols through both in vitro and in vivo experiments. Although, pre-contrast MRI images failed to reveal the ongoing pathology, contrast-enhanced MRI revealed hypoperfusion-triggered CNS injury in vascular dementia, unmasked amyloid-induced cerebrovascular activation in Alzheimer's disease and allowed monitoring of disease activity during experimental autoimmune encephalomyelitis. Moreover, contrast-enhanced MRI revealed the cerebrovascular cell activation associated with known risk factors of CNS disorders such as peripheral inflammation, ethanol consumption, hyperglycemia and aging. By providing a dramatically higher sensitivity than previously reported methods and molecular contrast agents, the technology described in the present study opens new avenues of investigation in the field of neuro-inflammation. (authors)

  9. Liver Imaging Reporting and Data System on CT and gadoxetic acid-enhanced MRI with diffusion-weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Dong Ik; Jang, Kyung Mi; Kim, Seong Hyun; Kang, Tae Wook; Song, Kyoung Doo [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of)

    2017-10-15

    To assess major imaging features of Liver Imaging Reporting and Data System (LI-RADS) on contrast-enhanced CT and gadoxetic acid-enhanced MRI and to estimate whether the combination of signal intensity favouring HCC on hepatobiliary phase (HBP) and diffusion-weighted images (DWI) can act as a major feature in LI-RADS. Four hundred twenty one patients with 445 observations were included. Major features of LI-RADS on CT and MRI as well as HBP and DWI features were assessed. Diagnostic performances of LR-5 according to LI-RADS v2014 and modified LI-RADS which incorporate combination of HBP and DWI were assessed. Pairwise comparisons of the receiver operating characteristic (ROC) curves were performed. For HCCs, capsule appearance had the highest rate of discordance between CT and MRI (32.7%), followed by washout appearance (22.2%). Specificity (75%) of LR-5 of LI-RADS v2014 was lower than that (77.1-79.2%) of modified LI-RADS. Area under the ROC curve of modified LI-RADS (0.755-0.775) was not significantly different from that of LI-RADS v 2014 (0.709) (p > 0.05). There were substantial discordances between CT and MRI for capsule and washout appearances in hepatic observations, and combination of gadoxetic acid-enhanced MRI and DWI might be able to be incorporated as a major feature of LI-RADS. (orig.)

  10. A sustainable energy-system in Latvia

    DEFF Research Database (Denmark)

    Rasmussen, Lotte Holmberg

    2003-01-01

    but a negative trade-balance. With this in mind, it is important that Latvia is able to meet the challenge and use the economic development to develop a sustainable energy-system and a sounder trade-balance. A combination of energy planning, national economy and innovation processes in boiler companies will form...

  11. Downscaling of Airborne Wind Energy Systems

    NARCIS (Netherlands)

    Fechner, U.; Schmehl, R.

    2016-01-01

    Airborne wind energy systems provide a novel solution to harvest wind energy from altitudes that can not be reached by wind turbines with a similar nominal generator power. The use of a lightweight but strong tether in place of an expensive tower provides an additional cost advantage, next to the

  12. Predicting the biological effects of mobile phone radiation absorbed energy linked to the MRI-obtained structure.

    Science.gov (United States)

    Krstić, Dejan; Zigar, Darko; Petković, Dejan; Sokolović, Dušan; Dinđić, Boris; Cvetković, Nenad; Jovanović, Jovica; Dinđić, Nataša

    2013-01-01

    The nature of an electromagnetic field is not the same outside and inside a biological subject. Numerical bioelectromagnetic simulation methods for penetrating electromagnetic fields facilitate the calculation of field components in biological entities. Calculating energy absorbed from known sources, such as mobile phones when placed near the head, is a prerequisite for studying the biological influence of an electromagnetic field. Such research requires approximate anatomical models which are used to calculate the field components and absorbed energy. In order to explore the biological effects in organs and tissues, it is necessary to establish a relationship between an analogous anatomical model and the real structure. We propose a new approach in exploring biological effects through combining two different techniques: 1) numerical electromagnetic simulation, which is used to calculate the field components in a similar anatomical model and 2) Magnetic Resonance Imaging (MRI), which is used to accurately locate sites with increased absorption. By overlapping images obtained by both methods, we can precisely locate the spots with maximum absorption effects. This way, we can detect the site where the most pronounced biological effects are to be expected. This novel approach successfully overcomes the standard limitations of working with analogous anatomical models.

  13. MRI in psychiatry

    International Nuclear Information System (INIS)

    Mulert, Christoph; Shenton, Martha E.

    2014-01-01

    This is the first comprehensive textbook on the use of MRI in psychiatry covering imaging techniques, brain systems and a review of findings in different psychiatric disorders. The book is divided into three sections, the first of which covers in detail all the major MRI-based methodological approaches available today, including fMRI, EEG-fMRI, DTI, and MR spectroscopy. In addition, the role of MRI in imaging genetics and combined brain stimulation and imaging is carefully explained. The second section provides an overview of the different brain systems that are relevant for psychiatric disorders, including the systems for perception, emotion, cognition, and reward. The final part of the book presents the MRI findings that are obtained in all the major psychiatric disorders using the previously discussed techniques. Numerous carefully chosen images support the informative text, making this an ideal reference work for all practitioners and trainees with an interest in this flourishing field.

  14. MRI in psychiatry

    Energy Technology Data Exchange (ETDEWEB)

    Mulert, Christoph [UKE, Hamburg (Germany). Psychiatry Neuroimaging Branch; Shenton, Martha E. (ed.) [Harvard Medical School, Boston, MA (United States). Dept. of Psychiatry and Radiology

    2014-07-01

    This is the first comprehensive textbook on the use of MRI in psychiatry covering imaging techniques, brain systems and a review of findings in different psychiatric disorders. The book is divided into three sections, the first of which covers in detail all the major MRI-based methodological approaches available today, including fMRI, EEG-fMRI, DTI, and MR spectroscopy. In addition, the role of MRI in imaging genetics and combined brain stimulation and imaging is carefully explained. The second section provides an overview of the different brain systems that are relevant for psychiatric disorders, including the systems for perception, emotion, cognition, and reward. The final part of the book presents the MRI findings that are obtained in all the major psychiatric disorders using the previously discussed techniques. Numerous carefully chosen images support the informative text, making this an ideal reference work for all practitioners and trainees with an interest in this flourishing field.

  15. NAPS renewable energy systems R and D

    International Nuclear Information System (INIS)

    Spiers, D.J.

    1990-01-01

    Neste Advanced Power Systems (NAPS) is a renewable energy systems company supplying complete power systems based on photovoltaics, wind turbine generator, diesel generators, or hybrid systems combining two or more of these. Except for a few demonstration systems linked to the electricity grid, these are stand-alone power supplies which include storage batteries. Our present market areas are: Domestic systems for remote houses, largely in the Nordic countries. Systems for developing countries, mostly for lighting, health care and water supply and industrial and professional systems for use anywhere in the world, mainly for telecommunications and navigation aids

  16. Distortion-free diffusion MRI using an MRI-guided Tri-Cobalt 60 radiotherapy system: Sequence verification and preliminary clinical experience.

    Science.gov (United States)

    Gao, Yu; Han, Fei; Zhou, Ziwu; Cao, Minsong; Kaprealian, Tania; Kamrava, Mitchell; Wang, Chenyang; Neylon, John; Low, Daniel A; Yang, Yingli; Hu, Peng

    2017-10-01

    Monitoring tumor response during the course of treatment and adaptively modifying treatment plan based on tumor biological feedback may represent a new paradigm for radiotherapy. Diffusion MRI has shown great promises in assessing and predicting tumor response to radiotherapy. However, the conventional diffusion-weighted single-shot echo-planar-imaging (DW-ssEPI) technique suffers from limited resolution, severe distortion, and possibly inaccurate ADC at low field strength. The purpose of this work was to develop a reliable, accurate and distortion-free diffusion MRI technique that is practicable for longitudinal tumor response evaluation and adaptive radiotherapy on a 0.35 T MRI-guided radiotherapy system. A diffusion-prepared turbo spin echo readout (DP-TSE) sequence was developed and compared with the conventional diffusion-weighted single-shot echo-planar-imaging sequence on a 0.35 T MRI-guided radiotherapy system (ViewRay). A spatial integrity phantom was used to quantitate and compare the geometric accuracy of the two diffusion sequences for three orthogonal orientations. The apparent diffusion coefficient (ADC) accuracy was evaluated on a diffusion phantom under both 0 °C and room temperature to cover a diffusivity range between 0.40 × 10 -3 and 2.10 × 10 -3 mm 2 /s. Ten room temperature measurements repeated on five different days were conducted to assess the ADC reproducibility of DP-TSE. Two glioblastoma (GBM) and six sarcoma patients were included to examine the in vivo feasibility. The target registration error (TRE) was calculated to quantitate the geometric accuracy where structural CT or MR images were co-registered to the diffusion images as references. ADC maps from DP-TSE and DW-ssEPI were calculated and compared. A tube phantom was placed next to patients not treated on ViewRay, and ADCs of this reference tube were also compared. The proposed DP-TSE passed the spatial integrity test (< 1 mm within 100 mm radius and < 2 mm within 175 mm radius

  17. Smart Cities and National Energy Systems

    DEFF Research Database (Denmark)

    Thellufsen, Jakob Zinck

    Energy system analysis follows two tracks, either through plans for future transitions of national energy systems, or local development of smart cities and regions. These two tracks seldom overlap. National plans neglect the local implementation of intermittent renewable technology and use of local...... resources, and smart cities and local development do not relate to national targets and fail to evaluate sub-optimization. Thus, there is a need for approaches that help researchers creating links between country analyses and local energy system transitions. This paper investigates the effects...... of such an approach, by investigating Western Denmark. By splitting Western Denmark into regions, it is possible to create individual energy systems for each region. Through interconnection, these regions can exchange electricity with each other. This enables analyses of interaction between smart cities and national...

  18. Energy and environmental management information systems

    Energy Technology Data Exchange (ETDEWEB)

    Martin, P.K. (Energy Auditing Agency Ltd., Milton Keynes (United Kingdom))

    1993-01-01

    The threat of global warming, environmental instability and the possible use of green or carbon taxes on fossil fuels has increased the need for energy efficiency. Energy Conservation is now recognised as one of the easiest and most cost-effective ways of limiting or reducing CO[sub 2] emissions. Large UK companies are now assessing how much CO[sub 2] they dissipate to the environment and reviewing strategies to reduce this either in response to consumer demand or as a corporate policy decision. Computer-based information systems already exist to monitor and report on fluctuations in energy consumption. These are called Monitoring and Targeting (M and T) systems. This paper explains what M and T systems are and how they are being extended to cover reporting on corporate fuel-based CO[sub 2] emissions to help provide an integrated energy and environmental-management information system. (author).

  19. Description of the Energy System of Spain

    Energy Technology Data Exchange (ETDEWEB)

    Caldes, N; Lechon, Y; Labriet, M; Cabal, H; Rua, C de la; Saez, R; Varela, M

    2008-07-01

    The objective of this report is to describe the complete Spain energy system, in order to make possible its modelling with the TIMES model within the NEEDS project (http://www.needs-project.org). (Author) 56 refs.

  20. Potential future waste-to-energy systems

    OpenAIRE

    Thorin, Eva; Guziana, Bozena; Song, Han; Jääskeläinen, Ari; Szpadt, Ryszard; Vasilic, Dejan; Ahrens, Thorsten; Anne, Olga; Lõõnik, Jaan

    2012-01-01

    This report discusses potential future systems for waste-to-energy production in the Baltic Sea Region, and especially for the project REMOWE partner regions, the County of Västmanland in Sweden, Northern Savo in Finland, Lower Silesia in Poland, western part of Lithuania and Estonia. The waste-to-energy systems planned for in the partner regions are combustion of municipal solid waste (MSW) and solid recovered fuels from household and industry as well as anaerobic digestion of sewage sludge ...

  1. Practical aspects of decentralized wind energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Beurskens, H J.M.

    1982-11-01

    Some practical aspects of wind energy systems are described with emphasis on small wind energy conversion systems, both horizontal and vertical axis turbines. Reviewed are the power train of the installation including the speed control and power construction. Power efficiency of small wind turbines available and in operation in the Netherlands is dealt with. Environmental aspects such as noise, disturbance of tv and radio signals, impact on birds and the landscape are mentioned briefly.

  2. Technical Design of Flexible Sustainable Energy Systems

    DEFF Research Database (Denmark)

    Lund, Henrik

    2003-01-01

    The paper presents technical designs of potential future flexible energy systems in Denmark, which will be able both to balance production and demand and to secure voltage and frequency requirements on the grid.......The paper presents technical designs of potential future flexible energy systems in Denmark, which will be able both to balance production and demand and to secure voltage and frequency requirements on the grid....

  3. 3rd annual biomass energy systems conference

    Energy Technology Data Exchange (ETDEWEB)

    1979-10-01

    The main objectives of the 3rd Annual Biomass Energy Systems Conference were (1) to review the latest research findings in the clean fuels from biomass field, (2) to summarize the present engineering and economic status of Biomass Energy Systems, (3) to encourage interaction and information exchange among people working or interested in the field, and (4) to identify and discuss existing problems relating to ongoing research and explore opportunities for future research. Abstracts for each paper presented were edited separately. (DC)

  4. Robot-assisted biopsies in a high-field MRI system. First clinical results

    International Nuclear Information System (INIS)

    Schell, B.; Eichler, K.; Mack, M.G.; Mueller, C.; Kerl, J.M.; Beeres, M.; Thalhammer, A.; Vogl, T.J.; Zangos, S.; Czerny, C.

    2012-01-01

    Purpose: The purpose of this study was to examine the clinical use of MR-guided biopsies in patients with suspicious lesions using a new MR-compatible assistance system in a high-field MR system. Materials and Methods: Six patients with suspicious focal lesions in various anatomic regions underwent percutanous biopsy in a high-field MR system (1.5 T, Magnetom Espree, Siemens) using a new MR-compatible assistance system (Innomotion). The procedures were planned and guided using T1-weighted FLASH and TrueFISP sequences. A servopneumatic drive then moved the guiding arm automatically to the insertion point. An MRI compatible 15G biopsy system (Somatex) was introduced by a physician guided by the needle holder and multiple biopsies were performed using the coaxial technique. The feasibility, duration of the intervention and biopsy findings were analyzed. Results: The proposed new system allows accurate punctures in a high-field MR system. The assistance device did not interfere with the image quality, and guided the needle virtually exactly as planned. Histological examination could be conducted on every patient. The lesion was malignant in four cases, and an infectious etiology was diagnosed for the two remaining lesions. Regarding the differentiation of anatomical and pathological structures and position monitoring of the insertion needle, TrueFISP images are to be given preference. The average intervention time was 41 minutes. Lesions up to 15.4 cm beneath the skin surface were punctured. Conclusion: The proposed MR-guided assistance system can be successfully utilized in a high-field MR system for accurate punctures of even deep lesions in various anatomic regions. (orig.)

  5. The captains of energy systems dynamics from an energy perspective

    CERN Document Server

    Prantil, Vincent C

    2015-01-01

    In teaching an introduction to transport or systems dynamics modeling at the undergraduate level, it is possible to lose pedagogical traction in a sea of abstract mathematics. What the mathematical modeling of time-dependent system behavior offers is a venue in which students can be taught that physical analogies exist between what they likely perceive as distinct areas of study in the physical sciences. We introduce a storyline whose characters are superheroes that store and dissipate energy in dynamic systems. Introducing students to the overarching conservation laws helps develop the analog

  6. High energy density, long life energy storage capacitor dielectric system

    International Nuclear Information System (INIS)

    Nichols, D.H.; Wilson, S.R.

    1977-01-01

    The evolution of energy storage dielectric systems shows a dramatic improvement in life and joule density, culminating in a 50% to 300% life improvement of polypropylene film-paper-phthalate ester over paper-castor oil depending on service. The physical and electrical drawbacks of castor oil are not present in the new system, allowing the capacitor designer to utilize the superior insulation resistance, dielectric strength, and corona resistance to full advantage. The result is longer life for equal joule density or greater joule density for equal life. Field service proof of the film-Geconol system superiority is based on 5 megajoule in operation and 16 megajoule on order

  7. WIND ENERGY CONVERSION SYSTEMS - A TECHNICAL REVIEW

    Directory of Open Access Journals (Sweden)

    N. RAMESH BABU

    2013-08-01

    Full Text Available Wind power production has been under the main focus for the past decade in power production and tremendous amount of research work is going on renewable energy, specifically on wind power extraction. Wind power provides an eco-friendly power generation and helps to meet the national energy demand when there is a diminishing trend in terms of non-renewable resources. This paper reviews the modeling of Wind Energy Conversion Systems (WECS, control strategies of controllers and various Maximum Power Point Tracking (MPPT technologies that are being proposed for efficient production of wind energy from the available resource.

  8. The challenge of greening energy systems

    International Nuclear Information System (INIS)

    Joseph, A.; Hughes, L.

    2006-01-01

    The current state of world energy supply and demand was examined along with future challenges facing population growth, economic growth, energy-demand growth, fossil energy supply, technology improvements, renewable energy solutions, and conservation measures. It was suggested that in order to implement cleaner and greener energy technology, it is important to understand the nature of global energy systems. The challenge of defining the related ideologies of green energy and sustainability was discussed. In this paper, green energy was defined as indicating environmental compatibility with little or no negative environmental impact. This differs from the concept of sustainability, which was defined as an action that can be repeated continuously without depleting or diminishing resources. In general, green energy options include most technologies that do not involve fossil fuels. However, this paper considered a spectrum of shades of green with some options being low-impact and cleaner, and others having high environmental impacts. As an example, the authors presented the ongoing debate over nuclear energy and hydro power. Although both energy sources can be sustainable over hundreds of years, they may or may not be environmentally compatible because they are often considered to have problematic attributes. Energy from renewable sources currently accounts for less than 20 per cent of world primary energy supply because price and implementation challenges in the renewables sector do not generally compare well to other energy sources. With high energy-demands beginning to strain finite fossil-energy supplies, the energy sector is now subject to more frequent disruptions and price fluctuations. Future growth from emerging economies will demand more energy and resources. This paper also emphasized that the proportion of green sources of energy has not increased substantially in the past 3 decades, and despite many technological advances, there continue to be significant

  9. The challenge of greening energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, A.; Hughes, L. [Dalhousie Univ., Halifax, NS (Canada). Dept. of Electrical and Computer Engineering, Energy Research Group

    2006-07-01

    The current state of world energy supply and demand was examined along with future challenges facing population growth, economic growth, energy-demand growth, fossil energy supply, technology improvements, renewable energy solutions, and conservation measures. It was suggested that in order to implement cleaner and greener energy technology, it is important to understand the nature of global energy systems. The challenge of defining the related ideologies of green energy and sustainability was discussed. In this paper, green energy was defined as indicating environmental compatibility with little or no negative environmental impact. This differs from the concept of sustainability, which was defined as an action that can be repeated continuously without depleting or diminishing resources. In general, green energy options include most technologies that do not involve fossil fuels. However, this paper considered a spectrum of shades of green with some options being low-impact and cleaner, and others having high environmental impacts. As an example, the authors presented the ongoing debate over nuclear energy and hydro power. Although both energy sources can be sustainable over hundreds of years, they may or may not be environmentally compatible because they are often considered to have problematic attributes. Energy from renewable sources currently accounts for less than 20 per cent of world primary energy supply because price and implementation challenges in the renewables sector do not generally compare well to other energy sources. With high energy-demands beginning to strain finite fossil-energy supplies, the energy sector is now subject to more frequent disruptions and price fluctuations. Future growth from emerging economies will demand more energy and resources. This paper also emphasized that the proportion of green sources of energy has not increased substantially in the past 3 decades, and despite many technological advances, there continue to be significant

  10. MRI-guided trephine biopsy and fine-needle aspiration in the diagnosis of bone lesions in low-field (0.23 T) MRI system using optical instrument tracking

    International Nuclear Information System (INIS)

    Blanco Sequeiros, Roberto; Klemola, Rauli; Ojala, Risto; Jyrkinen, Lasse; Tervonen, Osmo; Lappi-Blanco, Elisa; Soini, Ylermi

    2002-01-01

    The purpose of this study was to evaluate the feasibility of MRI-guided bone biopsy with optical instrument tracking and evaluate advantage of combined fine-needle aspiration (FNA) with trephine biopsy. Twenty trephine bone biopsies and 13 FNAs were performed under MRI and CT guidance in 14 patients. Informed consent was obtained from all patients. The evaluation of diagnostic accuracy was achieved by comparing the histopathological and cytological diagnosis with current or final diagnosis made during 6-month clinical follow-up. A 0.23-T open MRI scanner with interventional tools (Outlook Proview, Marconi Medical Systems, Cleveland, Ohio) was used. A surface coil was used. For trephine biopsy MRI-compatible bone biopsy set (Daum medical, Schwerin, Germany) was used. The FNA was performed with MRI compatible 20-G needle (Cook, Bloomington, Ind.). The diagnostic accuracy of MRI-guided trephine biopsy was 95%. The FNA sample diagnosis concurred with the histological in 54%. Our results show that MRI guidance in bone biopsies is accurate and safe. It is comparable to CT-guided or open biopsy. The role of combined FNA with bone biopsies remains controversial. (orig.)

  11. Optimisation of integrated energy and materials systems

    International Nuclear Information System (INIS)

    Gielen, D.J.; Okken, P.A.

    1994-06-01

    To define cost-effective long term CO2 reduction strategies an integrated energy and materials system model for the Netherlands for the period 2000-2040 is developed. The model is based upon the energy system model MARKAL, which configures an optimal mix of technologies to satisfy the specified energy and product/materials service demands. This study concentrates on CO 2 emission reduction in the materials system. For this purpose, the energy system model is enlarged with a materials system model including all steps 'from cradle to grave'. The materials system model includes 29 materials, 20 product groups and 30 waste materials. The system is divided into seven types of technologies; 250 technologies are modeled. The results show that the integrated optimisation of the energy system and the materials system can significantly reduce the emission reduction costs, especially at higher reduction percentages. The reduction is achieved through shifts in materials production and waste handling and through materials substitution in products. Shifts in materials production and waste management seem cost-effective, while the cost-effectiveness of shifts in product composition is sensitive due to the cost structure of products. For the building sector, transportation applications and packaging, CO 2 policies show a significant impact on prices, and shifts in product composition could occur. For other products, the reduction through materials substitution seems less promising. The impact on materials consumption seems most significant for cement (reduced), timber and aluminium (both increased). For steel and plastics, the net effect is balanced, but shifts between applications do occur. The MARKAL-approach is feasible to study integrated energy and materials systems. The progress compared to other environmental system analysis instruments is much more insight in the interaction of technologies on a national scale and in time

  12. Design for Reliability in Renewable Energy Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Zhou, Dao; Sangwongwanich, Ariya

    2017-01-01

    Power electronics are widely used in renewable energy systems to achieve lower cost of energy, higher efficiency and high power density. At the same time, the high reliability of the power electronics products is demanded, in order to reduce the failure rates and ensure cost-effective operation...... of the renewable energy systems. This paper thus describes the basic concepts used in reliability engineering, and presents the status and future trends of Design for Reliability (DfR) in power electronics, which is currently undergoing a paradigm shift to a physics-of-failure approach. Two case studies of a 2 MW...

  13. Optical Energy Transfer and Conversion System

    Science.gov (United States)

    Hogan, Bartholomew P. (Inventor); Stone, William C. (Inventor)

    2018-01-01

    An optical energy transfer and conversion system comprising a fiber spooler and an electrical power extraction subsystem connected to the spooler with an optical waveguide. Optical energy is generated at and transferred from a base station through fiber wrapped around the spooler, and ultimately to the power extraction system at a remote mobility platform for conversion to another form of energy. The fiber spooler may reside on the remote mobility platform which may be a vehicle, or apparatus that is either self-propelled or is carried by a secondary mobility platform either on land, under the sea, in the air or in space.

  14. State energy-price system: 1981 update

    Energy Technology Data Exchange (ETDEWEB)

    Fang, J.M.; Imhoff, K.L.; Hood, L.J.

    1983-08-01

    This report updates the State Energy Price Data System (STEPS) to include state-level energy prices by fuel and by end-use sectors for 1981. Both physical unit prices and Btu prices are presented. Basic documentation of the data base remains generally the same as in the original report: State Energy Price System; Volume 1: Overview and Technical Documentation (DOE/NBB-0029 Volume 1 of 2, November 1982). The present report documents only the changes in procedures necessitated by the update to 1981 and the corrections to the basic documentation.

  15. Synchronous generator wind energy conversion control system

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, A.L.R. [Wind Energy Group, Recife (Brazil); Lima, A.M.N.; Jacobina, C.B.; Simoes, F.J. [DEE, Campina Grande (Brazil)

    1996-12-31

    This paper presents the performance evaluation and the design of the control system of a WECS (Wind Energy Conversion System) that employs a synchronous generator based on its digital simulation. The WECS discussed in this paper is connected to the utility grid through two Pulse Width Modulated (PWM) power converters. The structure of the proposed WECS enables us to achieve high performance energy conversion by: (i) maximizing the wind energy capture and (ii) minimizing the reactive power flowing between the grid and the synchronous generator. 8 refs., 19 figs.

  16. Future development of nuclear energy systems

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Nuclear energy development in Japan has passed about 30 years, and reaches to a step to supply about 35 % of total electric power demand. However, together with globalization of economic and technical development, its future progressing method is required for its new efforts. Among such conditions, when considering a state of future type nuclear energy application, its contribution to further environmental conservation and international cooperation is essential, and it is required for adoption to such requirement how it is made an energy source with excellent economics.The Research Committee on 'Engineering Design on Nuclear Energy Systems' established under recognition in 1998 has been carried out some discussions on present and future status of nuclear energy development. And so forth under participation of outer specialists. Here were summarized on two year's committee actions containing them and viewpoints of nuclear industries, popularization of nuclear system technology, and so forth. (G.K.)

  17. Ultra-high field MRI: Advancing systems neuroscience towards mesoscopic human brain function

    NARCIS (Netherlands)

    Dumoulin, Serge O; Fracasso, A.; Van der Zwaag, W.; Siero, Jeroen C W; Petridou, Natalia

    2018-01-01

    Human MRI scanners at ultra-high magnetic field strengths of 7 T and higher are increasingly available to the neuroscience community. A key advantage brought by ultra-high field MRI is the possibility to increase the spatial resolution at which data is acquired, with little reduction in image

  18. WE-FG-202-08: Assessment of Treatment Response Via Longitudinal Diffusion MRI On A MRI-Guided System: Initial Experience of Quantitative Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Qi, X; Yang, Y; Yang, L; Low, D; Sheng, K [UCLA, Los Angeles, CA (United States)

    2016-06-15

    Purpose: To report our initial experience of systematic monitoring treatment response using longitudinal diffusion MR images on a Co-60 MRI-guided radiotherapy system. Methods: Four patients, including 2 head-and-necks, 1 sarcoma and 1 GBM treated on a 0.35 Tesla MRI-guided treatment system, were analyzed. For each patient, 3D TrueFISP MRIs were acquired during CT simulation and before each treatment for treatment planning and patient setup purposes respectively. Additionally, 2D diffusion-weighted MR images (DWI) were acquired weekly throughout the treatment course. The gross target volume (GTV) and brainstem (as a reference structure) were delineated on weekly 3D TrueFISP MRIs to monitor anatomy changes, the contours were then transferred onto the corresponding DWI images after fusing with the weekly TrueFISP images. The patient-specific temporal and spatial variations during the entire treatment course, such as anatomic changes, target apparent diffusion coefficient (ADC) distribution were evaluated in a longitudinal pattern. Results: Routine MRI revealed progressive soft-tissue GTV volume changes (up to 53%) for the H&N cases during the treatment course of 5–7 weeks. Within the GTV, the mean ADC values varied from −44% (ADC decrease) to +26% (ADC increase) in a week. The gradual increase of ADC value was inversely associated with target volume variation for one H&N case. The maximal changes of mean ADC values within the brainstem were 5.3% for the H&N cases. For the large size sarcoma and GBM tumors, spatial heterogeneity and temporal variations were observed through longitudinal ADC analysis. Conclusion: In addition to the superior soft-tissue visualization, the 0.35T MR system on ViewRay showed the potential to quantitatively measure the ADC values for both tumor and normal tissues. For normal tissue that is minimally affected by radiation, its ADC values are reproducible. Tumor ADC values show temporal and spatial fluctuation that can be exploited for

  19. Modeling and Simulation of Smart Energy Systems

    DEFF Research Database (Denmark)

    Connolly, David; Lund, Henrik; Mathiesen, Brian Vad

    2015-01-01

    At a global level, it is essential that the world transfers from fossil fuels to renewable energy resources to minimize the implications of climate change, which has been clearly demonstrated by the Intergovernmental Panel on Climate Change (IPCC, 2007a). At a national level, for most countries, ...... are presented on individual technologies and complete energy system strategies, which outline how it is possible to reach a 100% renewable energy system in the coming decades.......At a global level, it is essential that the world transfers from fossil fuels to renewable energy resources to minimize the implications of climate change, which has been clearly demonstrated by the Intergovernmental Panel on Climate Change (IPCC, 2007a). At a national level, for most countries......, the transition to renewable energy will improve energy security of supply, create new jobs, enhance trade, and consequently grow the national economy. However, even with such promising consequences, renewable energy only provided approximately 13% of the world's energy in 2007 (International Energy Agency, 2009a...

  20. Guidelines for Datacenter Energy Information System

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Reshma [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mahdavi, Rod [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mathew, Paul [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Granderson, Jessica [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shukla, Yash [Center for Environmental Planning and Technology (CEPT) Univ., Ahmedabad (India)

    2013-12-01

    The purpose of this document is to provide structured guidance to data center owners, operators, and designers, to empower them with information on how to specify and procure data center energy information systems (EIS) for managing the energy utilization of their data centers. Data centers are typically energy-intensive facilities that can consume up to 100 times more energy per unit area than a standard office building (FEMP 2013). This guidance facilitates “data-driven decision making,” which will be enabled by following the approach outlined in the guide. This will bring speed, clarity, and objectivity to any energy or asset management decisions because of the ability to monitor and track an energy management project’s performance.

  1. Integrated transport and renewable energy systems

    DEFF Research Database (Denmark)

    Mathiesen, B.V.; Lund, H.; Nørgård, Per Bromand

    2007-01-01

    Governments worldwide aim at reducing CO2 emissions and expanding renewable energy. A key element in achieving such a goal is to use renewable energy in transport such as biofuels. However, efforts to promote single transport technologies and single fuels only represent a partial solution...... transport. It is concluded that a 100 per cent renewable energy transport system is possible but is connected to significant challenges in the path towards it. Biomass is a limited resource and it is important to avoid effecting the production. The integration of the transport with the remaining energy....... No single technology can solve the problem of ever increasing CO2 emissions from transport. Transport must be integrated into energy planning, as electricity and heating. In this paper, a coherent effort to integrate transport into energy planning is proposed, using multiple means promoting sustainable...

  2. Energy condensed packaged systems. Composition, production, properties

    Directory of Open Access Journals (Sweden)

    Igor L. Kovalenko

    2015-03-01

    Full Text Available In this paper it is presented the substantiation of choice of fuel phase composition and optimal technology of emulsion production on the basis of binary solution of ammonium and calcium nitrates, which provide the obtaining of energy condensed packaged systems with specified properties. The thermal decomposition of energy condensed systems on the basis of ammonium nitrate is investigated. It is shown that the fuel phase of emulsion systems should be based on esters of polyunsaturated acids or on combinations thereof with petroleum products. And ceresin or petroleum wax can be used as the structuring additive. The influence of the technology of energy condensed systems production on the physicochemical and detonation parameters of emulsion explosives is considered. It is shown the possibility of obtaining of emulsion systems with dispersion of 1.3...1.8 microns and viscosity higher than 103 Pa∙s in the apparatus of original design. The sensitizing effect of chlorinated paraffin CP-470 on the thermolysis of energy condensed emulsion system is shown. The composition and production technology of energy condensed packaged emulsion systems of mark Ukrainit-P for underground mining in mines not dangerous on gas and dust are developed.

  3. Nuclear technologies for local energy systems

    International Nuclear Information System (INIS)

    McDonnell, F.N.; Lynch, G.F.

    1990-03-01

    If nuclear energy is to realize its full potential as a safe and cost-effective alternative to fossil fuels, applications beyond those that are currently being serviced by large, central nuclear power stations must be identified and appropriate reactors developed. The Canadian program on reactor systems for local energy supply is at the forefront of these developments. This program emphasizes design simplicity, low power density and fuel rating, reliance on natural processes, passive systems, and reduced reliance on operator action. The first product, the SLOWPOKE Energy System, is a 10 MW heat source specifically designed to provide hot water to satisfy the needs of local heating systems for building complexes, institutions and municipal district heating systems. A demonstration heating reactor has been constructed at the Whiteshell Nuclear Research Establishment in Manitoba and has been undergoing an extensive test program since first operation in 1987 July. Based on the knowledge learned from the design, construction, licensing and operational testing of this facility, the design of the 10 MW commercial-size unit is well advanced, and Atomic Energy of Canada Limited is prepared to commit the construction of the first commercial unit. Although the technical demonstration of the concept is important, it is recognized that another crucial element is the public and regulatory acceptance of small nuclear systems in urban areas. The decision by a community to commit the construction of a SLOWPOKE Energy System brings to a sharp focus the current public apprehension about nuclear technologies

  4. Advanced energy system with nuclear reactors as an energy source

    International Nuclear Information System (INIS)

    Kato, Y.; Ishizuka, T.; Nikitin, K.

    2007-01-01

    About two-thirds of the energy generated in a light water reactors (LWRs) core is currently dissipated to the ocean as lukewarm water through steam condensers; more than half the energy in helium (He) gas turbine high temperature gas cooled reactors (HTGRs) is dissipated through pre-coolers and inter coolers. The new waste heat recovery system efficiently recovers the waste heat from reactors using boiling heat transfer of 20 degree C liquid carbon dioxide (CO 2 ) instead of conventional sea water as a cooling medium. The CO 2 gasified in the cooling process is used directly as a working fluid of mechanical heat pumps for hot water supply. In LWRs, the net energy utilization fraction to total heat generation in the core exceeds 85% through the waste heat recovery. This cogeneration system is about 2.5 times more effective than current systems in reducing global warming gas emissions and long half- life radioactive material accumulation. It also increases uranium resource utilization relative to current LWRs. In the HTGR cogeneration system, the waste heat is also useful for cold water supply by introducing an adsorption refrigeration system since the gas temperature is still as high as about 190 degree Celsius. When the heat recovery system is incorporated into the HTGR, the electricity to heat-supply ratio of the HTGR cogeneration system accommodates the demand ratio in cities well; it would be suited to dispersed energy sources. The heat supply cost is expected to be lower than those of conventional fossil-fired boilers beyond operation of about four years. The waste heat recovered is able to be utilized not only for local heat supply but also for methane and methanol production from waste products of cities and farms through high-temperature fermentation, e.g., garbage, waste wood and used paper that are produced in cities, along with excreta produced through farming. The methane and methanol can be used to generate hydrogen for fuel cells. The new waste heat

  5. Gradient pre-emphasis to counteract first-order concomitant fields on asymmetric MRI gradient systems.

    Science.gov (United States)

    Tao, Shengzhen; Weavers, Paul T; Trzasko, Joshua D; Shu, Yunhong; Huston, John; Lee, Seung-Kyun; Frigo, Louis M; Bernstein, Matt A

    2017-06-01

    To develop a gradient pre-emphasis scheme that prospectively counteracts the effects of the first-order concomitant fields for any arbitrary gradient waveform played on asymmetric gradient systems, and to demonstrate the effectiveness of this approach using a real-time implementation on a compact gradient system. After reviewing the first-order concomitant fields that are present on asymmetric gradients, we developed a generalized gradient pre-emphasis model assuming arbitrary gradient waveforms to counteract their effects. A numerically straightforward, easily implemented approximate solution to this pre-emphasis problem was derived that was compatible with the current hardware infrastructure of conventional MRI scanners for eddy current compensation. The proposed method was implemented on the gradient driver subsystem, and its real-time use was tested using a series of phantom and in vivo data acquired from two-dimensional Cartesian phase-difference, echo-planar imaging, and spiral acquisitions. The phantom and in vivo results demonstrated that unless accounted for, first-order concomitant fields introduce considerable phase estimation error into the measured data and result in images with spatially dependent blurring/distortion. The resulting artifacts were effectively prevented using the proposed gradient pre-emphasis. We have developed an efficient and effective gradient pre-emphasis framework to counteract the effects of first-order concomitant fields of asymmetric gradient systems. Magn Reson Med 77:2250-2262, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  6. Energy Systems Analysis of Waste to Energy Technologies by use of EnergyPLAN

    DEFF Research Database (Denmark)

    Münster, Marie

    Even when policies of waste prevention, re-use and recycling are prioritised, a fraction of waste will still be left which can be used for energy recovery. This report asks the question: How to utilise waste for energy in the best way seen from an energy system perspective? Eight different Waste......-to-Energy technologies are compared with a focus on fuel efficiency, CO2 reductions and costs. The comparison is made by conducting detailed energy system analyses of the present system as well as a potential future Danish energy system with a large share of combined heat and power and wind power. The study shows...... the potential of using waste for the production of transport fuels such as upgraded biogas and petrol made from syngas. Biogas and thermal gasification technologies are interesting alternatives to waste incineration and it is recommended to support the use of biogas based on manure and organic waste. It is also...

  7. Trust and the transformation of energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Rayner, Steve [James Martin Institute for Science and Civilization, Said Business School, Park End Street, Oxford, OX1 1HP (United Kingdom)

    2010-06-15

    The author looks at diverse concepts and roles of trust in the challenge of decarbonising energy systems, drawing on 25 years of personal experience in the fields of energy and environmental policy research. The paper focuses on three issues-public trust in science, institutional trust in making technology choices, and the idea that high-trust societies are more sustainable than those exhibiting low-trust. While trust is a key concept in understanding the public acceptability of technology choices, it is only one of a suite of interrelated concepts that must be addressed, which also includes liability, consent, and fairness. Furthermore, rational distrust among competing institutional world views may be critical in understanding the role of social capital in socioeconomic and technological development. Thus the concept of trust has become a portmanteau, carrying a diverse range of ideas and conditions for sustainable energy systems. The paper concludes with three emphases for decision makers. First, the issue is the energy system, not particular generating technologies. Second, the energy system must be recognized to be as much a social system as it is a technical one. Third, the system requires incorporation of the minimum level of diversity of engineering technologies and social actors to be sustainable. (author)

  8. Renewable Energy Systems: Technology Overview and Perspectives

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Ionel, Dan M.; Yang, Yongheng

    2017-01-01

    In this chapter, essential statistics demonstrating the increasing role of renewable energy generation are first discussed. A state-of-the-art review section covers the fundamentals of wind turbine and photovoltaic (PV) systems. Schematic diagrams illustrating the main components and system topol......, including PV and concentrating solar power; wave energy; fuel cells; and storage with batteries and hydrogen, respectively. Recommended further readings on topics of electric power engineering for renewable energy are included in the final section.......In this chapter, essential statistics demonstrating the increasing role of renewable energy generation are first discussed. A state-of-the-art review section covers the fundamentals of wind turbine and photovoltaic (PV) systems. Schematic diagrams illustrating the main components and system...... topologies are included. Also, the increasing role of power electronics is explained as an enabler for renewable energy integration and for future power systems and smart grids. Recent examples of research and development, including new devices and system installations for utility power plants...

  9. Trust and the transformation of energy systems

    International Nuclear Information System (INIS)

    Rayner, Steve

    2010-01-01

    The author looks at diverse concepts and roles of trust in the challenge of decarbonising energy systems, drawing on 25 years of personal experience in the fields of energy and environmental policy research. The paper focuses on three issues-public trust in science, institutional trust in making technology choices, and the idea that high-trust societies are more sustainable than those exhibiting low-trust. While trust is a key concept in understanding the public acceptability of technology choices, it is only one of a suite of interrelated concepts that must be addressed, which also includes liability, consent, and fairness. Furthermore, rational distrust among competing institutional world views may be critical in understanding the role of social capital in socioeconomic and technological development. Thus the concept of trust has become a portmanteau, carrying a diverse range of ideas and conditions for sustainable energy systems. The paper concludes with three emphases for decision makers. First, the issue is the energy system, not particular generating technologies. Second, the energy system must be recognized to be as much a social system as it is a technical one. Third, the system requires incorporation of the minimum level of diversity of engineering technologies and social actors to be sustainable.

  10. High Tc superconducting energy storage systems

    Energy Technology Data Exchange (ETDEWEB)

    Werfel, Frank [Adelwitz Technologiezentrum GmbH (ATZ), Arzberg-Adelwitz (Germany)

    2012-07-01

    Electric energy is basic to heat and light our homes, to power our businesses and to transport people and goods. Powerful storage techniques like SMES, Flywheel, Super Capacitor, and Redox - Flow batteries are needed to increase the overall efficiency, stability and quality of electrical grids. High-Tc superconductors (HTS) possess superior physical and technical properties and can contribute in reducing the dissipation and losses in electric machines as motors and generators, in electric grids and transportation. The renewable energy sources as solar, wind energy and biomass will require energy storage systems even more as a key technology. We survey the physics and the technology status of superconducting flywheel energy storage (FESS) and magnetic energy storage systems (SMES) for their potential of large-scale commercialization. We report about a 10 kWh / 250 kW flywheel with magnetic stabilization of the rotor. The progress of HTS conductor science and technological engineering are basic for larger SMES developments. The performance of superconducting storage systems is reviewed and compared. We conclude that a broad range of intensive research and development in energy storage is urgently needed to produce technological options that can allow both climate stabilization and economic development.

  11. Exergy Analysis of Complex Ship Energy Systems

    Directory of Open Access Journals (Sweden)

    Pierre Marty

    2016-04-01

    Full Text Available With multiple primary and secondary energy converters (diesel engines, steam turbines, waste heat recovery (WHR and oil-fired boilers, etc. and extensive energy networks (steam, cooling water, exhaust gases, etc., ships may be considered as complex energy systems. Understanding and optimizing such systems requires advanced holistic energy modeling. This modeling can be done in two ways: The simpler approach focuses on energy flows, and has already been tested, approved and presented; a new, more complicated approach, focusing on energy quality, i.e., exergy, is presented in this paper. Exergy analysis has rarely been applied to ships, and, as a general rule, the shipping industry is not familiar with this tool. This paper tries to fill this gap. We start by giving a short reminder of what exergy is and describe the principles of exergy modeling to explain what kind of results should be expected from such an analysis. We then apply these principles to the analysis of a large two-stroke diesel engine with its cooling and exhaust systems. Simulation results are then presented along with the exergy analysis. Finally, we propose solutions for energy and exergy saving which could be applied to marine engines and ships in general.

  12. Offshore Wind Energy Systems Engineering Curriculum Development

    Energy Technology Data Exchange (ETDEWEB)

    McGowan, Jon G. [Univ. of Massachusetts, Amherst, MA (United States); Manwell, James F. [Univ. of Massachusetts, Amherst, MA (United States); Lackner, Matthew A. [Univ. of Massachusetts, Amherst, MA (United States)

    2012-12-31

    Utility-scale electricity produced from offshore wind farms has the potential to contribute significantly to the energy production of the United States. In order for the U.S. to rapidly develop these abundant resources, knowledgeable scientists and engineers with sound understanding of offshore wind energy systems are critical. This report summarizes the development of an upper-level engineering course in "Offshore Wind Energy Systems Engineering." This course is designed to provide students with a comprehensive knowledge of both the technical challenges of offshore wind energy and the practical regulatory, permitting, and planning aspects of developing offshore wind farms in the U.S. This course was offered on a pilot basis in 2011 at the University of Massachusetts and the National Renewable Energy Laboratory (NREL), TU Delft, and GL Garrad Hassan have reviewed its content. As summarized in this report, the course consists of 17 separate topic areas emphasizing appropriate engineering fundamentals as well as development, planning, and regulatory issues. In addition to the course summary, the report gives the details of a public Internet site where references and related course material can be obtained. This course will fill a pressing need for the education and training of the U.S. workforce in this critically important area. Fundamentally, this course will be unique due to two attributes: an emphasis on the engineering and technical aspects of offshore wind energy systems, and a focus on offshore wind energy issues specific to the United States.

  13. The International Atomic Energy Agency's safeguards system

    International Nuclear Information System (INIS)

    Wagner, W.

    2000-01-01

    A system of international safeguards has been established to provide assurance that nuclear materials in civilian use are not diverted from their peaceful purpose. The safeguards system is administered by the International Atomic Energy Agency/Department of Safeguards and devolves from treaties and other international agreements. Inspectors from the Agency verify reports from States about nuclear facilities by audits, observation, and measurements. (author)

  14. Pulsed power liner for PLT energy systems

    International Nuclear Information System (INIS)

    Armellino, C.A.; Bronner, G.; Murray, J.G.

    1975-01-01

    PLT is Princeton University's latest Tokamak machine in the controlled thermonuclear fusion research effort. The OH (ohmic heating) and SF (shaping field) systems for the machine place a very high energy pulsed current load on the AC line feeding them. This paper describes the two systems and the steps taken to insure minimum effect on line regulation during the pulsed operation

  15. Applying Systems Engineering on Energy Challenges

    NARCIS (Netherlands)

    Safi, J.; Muller, G.; Bonnema, Gerrit Maarten

    2012-01-01

    Systems engineering is a discipline with methods and techniques to address complex problems. We want to study how Systems Engineering methods can help to address today's grand challenges, such as the energy problem. The first step is problem definition which aims at articulating the problem in its

  16. World Energy Projection System model documentation

    International Nuclear Information System (INIS)

    Hutzler, M.J.; Anderson, A.T.

    1997-09-01

    The World Energy Projection System (WEPS) was developed by the Office of Integrated Analysis and Forecasting within the Energy Information Administration (EIA), the independent statistical and analytical agency of the US Department of Energy. WEPS is an integrated set of personal computer based spreadsheets containing data compilations, assumption specifications, descriptive analysis procedures, and projection models. The WEPS accounting framework incorporates projections from independently documented models and assumptions about the future energy intensity of economic activity (ratios of total energy consumption divided by gross domestic product GDP), and about the rate of incremental energy requirements met by natural gas, coal, and renewable energy sources (hydroelectricity, geothermal, solar, wind, biomass, and other renewable resources). Projections produced by WEPS are published in the annual report, International Energy Outlook. This report documents the structure and procedures incorporated in the 1998 version of the WEPS model. It has been written to provide an overview of the structure of the system and technical details about the operation of each component of the model for persons who wish to know how WEPS projections are produced by EIA

  17. Kinetic energy recovery systems in motor vehicles

    Science.gov (United States)

    Śliwiński, C.

    2016-09-01

    The article draws attention to the increasing environmental pollution caused by the development of vehicle transport and motorization. Different types of design solutions used in vehicles for the reduction of fuel consumption, and thereby emission of toxic gasses into the atmosphere, were specified. Historical design solutions concerning energy recovery devices in mechanical vehicles which used flywheels to accumulate kinetic energy were shown. Developmental tendencies in the area of vehicle manufacturing in the form of hybrid electric and electric devices were discussed. Furthermore, designs of energy recovery devices with electrical energy storage from the vehicle braking and shock absorbing systems were presented. A mechanical energy storing device using a flywheel operating under vacuum was presented, as were advantages and disadvantages of both systems, the limitations they impose on individual constructions and safety issues. The paper also discusses a design concept of an energy recovery device in mechanical vehicles which uses torsion springs as the main components of energy accumulation during braking. The desirability of a cooperation of both the mechanical- and electrical energy recovery devices was indicated.

  18. World Energy Projection System model documentation

    Energy Technology Data Exchange (ETDEWEB)

    Hutzler, M.J.; Anderson, A.T.

    1997-09-01

    The World Energy Projection System (WEPS) was developed by the Office of Integrated Analysis and Forecasting within the Energy Information Administration (EIA), the independent statistical and analytical agency of the US Department of Energy. WEPS is an integrated set of personal computer based spreadsheets containing data compilations, assumption specifications, descriptive analysis procedures, and projection models. The WEPS accounting framework incorporates projections from independently documented models and assumptions about the future energy intensity of economic activity (ratios of total energy consumption divided by gross domestic product GDP), and about the rate of incremental energy requirements met by natural gas, coal, and renewable energy sources (hydroelectricity, geothermal, solar, wind, biomass, and other renewable resources). Projections produced by WEPS are published in the annual report, International Energy Outlook. This report documents the structure and procedures incorporated in the 1998 version of the WEPS model. It has been written to provide an overview of the structure of the system and technical details about the operation of each component of the model for persons who wish to know how WEPS projections are produced by EIA.

  19. ADRES : autonomous decentralized regenerative energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Brauner, G.; Einfalt, A.; Leitinger, C.; Tiefgraber, D. [Vienna Univ. of Technology (Austria)

    2007-07-01

    The autonomous decentralized regenerative energy systems (ADRES) research project demonstrates that decentralized network independent microgrids are the target power systems of the future. This paper presented a typical structure of a microgrid, demonstrating that all types of generation available can be integrated, from wind and small hydro to photovoltaic, fuel cell, biomass or biogas operated stirling motors and micro turbines. In grid connected operation the balancing energy and reactive power for voltage control will come from the public grid. If there is no interconnection to a superior grid, it will form an autonomous micro grid. In order to reduce peak power demand and base energy, autonomous microgrid technology requires highly efficient appliances. Otherwise large collector design, high storage and balancing generation capacities would be necessary, which would increase costs. End-use energy efficiency was discussed with reference to demand side management (DSM) strategies that match energy demand with actual supply in order to minimize the storage size needed. This paper also discussed network controls that comprise active and reactive power. Decentralized robust algorithms were investigated with reference to black-start ability and congestion management features. It was concluded that the trend to develop small decentralized grids in parallel to existing large systems will improve security of supply and reduce greenhouse gas emissions. Decentralized grids will also increase energy efficiency because regenerative energy will be used where it is collected in the form of electricity and heat, thus avoiding transport and the extension of transmission lines. Decentralized energy technology is now becoming more economic by efficient and economic mass production of components. Although decentralized energy technology requires energy automation, computer intelligence is becoming increasingly cost efficient. 2 refs., 4 figs.

  20. The role of electrolysers in energy system

    DEFF Research Database (Denmark)

    Ridjan, Iva; Hansen, Kenneth; Sorknæs, Peter

    Short and long-term role of electrolysis for grid balancing is investigated in this report, followed by an analysis on the feasibility of implementing electrolysis in the energy system and their potential for gas market balancing. Firstly, a literature review is conducted to determine the state......-of-the-art knowledge on using electrolysis for grid balancing. Secondly, based on Danish energy system models for 2020 and 2035, which can simulate the operation of electrolysis, the role of both alkaline and SOEC electrolysers is analysed in terms of electricity system balancing. Thirdly, different electrolyser...