WorldWideScience

Sample records for voltage electrical injury

  1. High Voltage Electrical Injuries In The University Of Calabar ...

    African Journals Online (AJOL)

    Background: Burn injuries are a common presentation in Nigerian hospitals and result from a variety of causes. Recently, many have resulted from Petroleum related fire incidents. High voltage electrical injuries are relatively rare; lightning strikes even rarer. In traditional societies where Traditional medicine practitioners are ...

  2. Electrical Injuries

    Science.gov (United States)

    ... it can pass through your body and cause injuries. These electrical injuries can be external or internal. You may have one or both types. External injuries are skin burns. Internal injuries include damage to ...

  3. Electrical injury in relation to voltage, "no-let-go" phenomenon, symptoms and perceived safety culture: a survey of Swedish male electricians.

    Science.gov (United States)

    Rådman, Lisa; Nilsagård, Ylva; Jakobsson, Kristina; Ek, Åsa; Gunnarsson, Lars-Gunnar

    2016-02-01

    Professional electricians are highly subjected to electrical injuries. Previous studies describing symptoms after electrical injury have not included people with less severe initial injuries. The purpose of the present study was to describe symptoms at different time points after electrical injury, the impact of "no-let-go" phenomenon and different electrical potential [high voltage (HV) vs. low voltage (LV)], and the safety culture at the workplace. A retrospective survey was conducted with 523 Swedish electricians. Two questionnaires were issued: the first to identify electricians who had experienced electrical injury and the second to gain information about symptoms and safety culture. Self-reported symptoms were described at different time points following injury. Symptoms for HV and LV accidents were compared. Occurrence or nonoccurrence of "no-let-go" phenomenon was analysed using two-tailed Chi-2. Safety culture was assessed with a validated questionnaire. Nearly all reported having symptoms directly after the injury, mainly paraesthesia and pain. For the first weeks after injury, pain and muscle weakness dominated. The most frequently occurring symptoms at follow-up were pain, muscle weakness and loss of sensation. HV injuries and "no-let go" phenomenon were associated with more sustained symptoms. Deficiencies in the reporting routines were present, as well as shortage of preventive measures. The results indicate that symptoms are reported also long time after an electrical injury and that special attention should be paid to HV injuries and "no-let go" accidents. The workplace routines to reduce the number of work-related electrical injuries for Swedish electricians can be improved.

  4. Development of Optic Neuropathy and Foveal Pseudocyst in a Case of High-Voltage Electrical Injury: A Three-Year Follow-Up

    Directory of Open Access Journals (Sweden)

    Sezin Akça Bayar

    2014-10-01

    Full Text Available A 35-year-old male patient had a decreased vision in his right eye, with a visual acuity of 20/400, after a high-voltage electrical injury. Corneal edema, Descemet’s membrane folds, cataract, macular hole, and optic neuropathy were detected in his right eye. Intravenous pulse steroids were administered. On the third day of treatment, the visual acuity in the right eye improved to 20/200 and the corneal edema resolved. Two months later, the patient’s visual acuity was still 20/200, while optic disc pallor, epiretinal gliosis, a non-fullthickness macular hole, and pseudo-cyst formation were detected in his right eye. Three years later, the macular pseudo-cyst formation transformed into an atrophic scar, while the patient’s visual acuity was the same. In conclusion, as a result of high-voltage electrical injury, serious ocular complications may develop. It is sufficient to refer those patients to an ophthalmologist for appropriate treatment and follow-up. (Turk J Ophthalmol 2014; 44: 410-2

  5. PREDICTION OF VOLTAGE FLUCTUATION IN ELECTRIC GRIDS

    Directory of Open Access Journals (Sweden)

    V.A. Sapryka

    2013-06-01

    Full Text Available A mathematical model of voltage fluctuation versus parameters of power quality and power consumption is developed to allow predicting parameters of the power quality in electric grids. Application of the model will result in an electrical complex functioning optimization

  6. High voltage electricity installations a planning perspective

    CERN Document Server

    Jay, Stephen Andrew

    2006-01-01

    The presence of high voltage power lines has provoked widespread concern for many years. High Voltage Electricity Installations presents an in-depth study of policy surrounding the planning of high voltage installations, discussing the manner in which they are percieved by the public, and the associated environmental issues. An analysis of these concerns, along with the geographical, environmental and political influences that shape their expression, is presented. Investigates local planning policy in an area of the energy sector that is of highly topical environmental and public concern Cover

  7. High voltage and electrical insulation engineering

    CERN Document Server

    Arora, Ravindra

    2011-01-01

    "The book is written for students as well as for teachers and researchers in the field of High Voltage and Insulation Engineering. It is based on the advance level courses conducted at TU Dresden, Germany and Indian Institute of Technology Kanpur, India. The book has a novel approach describing the fundamental concept of field dependent behavior of dielectrics subjected to high voltage. There is no other book in the field of high voltage engineering following this new approach in describing the behavior of dielectrics. The contents begin with the description of fundamental terminology in the subject of high voltage engineering. It is followed by the classification of electric fields and the techniques of field estimation. Performance of gaseous, liquid and solid dielectrics under different field conditions is described in the subsequent chapters. Separate chapters on vacuum as insulation and the lightning phenomenon are included"--

  8. Electrical system architecture having high voltage bus

    Science.gov (United States)

    Hoff, Brian Douglas [East Peoria, IL; Akasam, Sivaprasad [Peoria, IL

    2011-03-22

    An electrical system architecture is disclosed. The architecture has a power source configured to generate a first power, and a first bus configured to receive the first power from the power source. The architecture also has a converter configured to receive the first power from the first bus and convert the first power to a second power, wherein a voltage of the second power is greater than a voltage of the first power, and a second bus configured to receive the second power from the converter. The architecture further has a power storage device configured to receive the second power from the second bus and deliver the second power to the second bus, a propulsion motor configured to receive the second power from the second bus, and an accessory motor configured to receive the second power from the second bus.

  9. Electric Shock Injuries in Children

    Science.gov (United States)

    ... Issues Listen Español Text Size Email Print Share Electric Shock Injuries in Children Page Content ​When the ... comes into direct contact with a source of electricity, the current passes through it, producing what's called ...

  10. Electrical cardiac injuries: current concepts and management.

    Science.gov (United States)

    Waldmann, Victor; Narayanan, Kumar; Combes, Nicolas; Jost, Daniel; Jouven, Xavier; Marijon, Eloi

    2017-04-20

    Electrical injuries are a commonly encountered hazard in both the home and workplace. However, clinicians are often uncomfortable when faced with the patient who presents with an electric shock due to sparse literature and lack of systematic recommendations on this topic. Electrical injuries can range from minor skin burns to life threatening internal organ damage. A thorough clinical assessment to ascertain the path of current through the body and possible internal injury is essential. The main concern in an apparently stable individual after an electric shock is the potential for delayed occurrence of cardiac arrhythmias which will require monitoring in the intensive care setting. While it may be reasonable to discharge home from the emergency room selected patients with low voltage injuries, absence of syncope and a normal ECG, others may require monitoring for at least 24 h. Public education and increasing workplace as well as home safety measures are key steps in prevention. The present review summarizes current knowledge in pathophysiology, manifestations and management of electrical injuries, with specific focus on cardiac effects. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

  11. Electrical injury in construction workers: a special focus on injury with electrical power.

    Science.gov (United States)

    Salehi, Seyed Hamid; Fatemi, Mohammad Javad; Aśadi, Kamran; Shoar, Saeed; Ghazarian, Anita Der; Samimi, Rogeieh

    2014-03-01

    Electrical injury in construction workers due to contact with overhead power lines accounts for an important cause of admission at the emergency department. Due to lack of specific treatment options for this type of injury, prevention remains the mainstay of management. Our study aimed to demonstrate the characteristics of electrical injury in construction workers among one of the largest Iranian population at a burn care hospital. Through a retrospective review of hospital data base, patients with electrical injuries admitted to Motahari hospital in Tehran, Iran between March 2011 and June 2012 were included for analysis. Patients were divided into construction workers and other patients. Primary characteristics and final outcomes were then compared between the 2 study groups. Of 202 patients included in this study, 105 patients (52%) were construction workers and 97 patients (48%) constituted the remainder. There was significant difference between the 2 groups in terms of mean age, gender, and average burn size. In contrast, mean duration of hospitalization and mortality rate did not differ significantly between the 2 study groups (p>0.05). Contacts with over head power-lines accounted for the most common mechanism of injury. There was significant difference between the 2 groups in terms of place of injury and electrical current power. However, total cost of treatment did not differ significantly between the 2 groups (p>0.05). Frequency of severe complications was higher in construction workers and this group underwent more invasive procedures such as limb amputation and fasciotomy. The most common mechanism of electrical injuries in construction workers is due to contact with over head high voltage power-lines at workplace. This type of electrical injury is associated with higher use of fasciotomy, flap and limb amputation. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  12. Voltage Support from Electric Vehicles in Distribution Grid

    DEFF Research Database (Denmark)

    Huang, Shaojun; Pillai, Jayakrishnan Radhakrishna; Bak-Jensen, Birgitte

    2013-01-01

    The paper evaluates the voltage support functions from electric vehicles (EVs) on a typical Danish distribution grid with high EV penetration. In addition to the popular voltage control modes, such as voltage droop charging (low voltage level leads to low charging power) and reactive power support......, the combination of these two methods is also examined for controlled EV charging. Simulation results show that the combination of the two individual supporting methods has the best performance in terms of voltage regulation as well as improving EV penetration level at weak distribution grids....

  13. Effect of bleeding method and low voltage electrical stimulation on ...

    African Journals Online (AJOL)

    An early post mortem low voltage electrical stimulation (ES) of the carcasses also had no influence on the cooking loss, drip loss and colour of these muscles. Electrical stimulation did result in a lower pH45 in both the fillet and big drum muscles. However, after 24 h the pH of the muscles did not differ. Electrical stimulation ...

  14. Influence of Voltage on Main Characteristics of Electric Lighting Lamps

    Directory of Open Access Journals (Sweden)

    V. B. Kozlovskaya

    2009-01-01

    Full Text Available An analysis and systemization of data on influence of voltage value on main lighting engineering, electric and economic characteristics of incandescent lamps, gaseous-discharge lamps of low and high pressure have been made in the paper.Analytical and graphical dependences have been obtained that ensure to evaluate quantitative changes of corresponding lamp characteristics at voltage deviation from nominal value.

  15. Pyogenic Arthritis of the Ankle Joint Following a High-Voltage Electrical Burn in the Lower Extremity: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kuk Seon; Lee, Gyung Kyu; Kang, Ik Won; Hwang, Dae Hyun; Lee, Eil Seong; Min, Seon Jung; Han, You Mie [Dept. of Radiology, Hangang Scared Heart Hospital, Hallym University College of Medicine, Seoul (Korea, Republic of); Lee, Eil Seong [Dept.of Radiology, Gyeongju Hospital, Dongguk University College of Medicine, Gyeongju (Korea, Republic of)

    2011-04-15

    A high-voltage electrical burn caused extensive deep muscle injuries beneath a relatively small skin wound at the contact point. Hidden, undetected deep muscle injuries have a tendency for progressive tissue necrosis, which can lead to major amputations or sepsis. The radiologic features of this rare, sometimes life-threatening injury have occasionally been described in the literature. However, to the best of our knowledge, there have been no reports on a case of pyogenic arthritis of the ankle joint following a high-voltage electrical burn involving the lower extremity. We report a case of the pyogenic arthritis of the ankle joint following a high-voltage electrical burn involving the lower extremity.

  16. Static Electricity as Part of Electromagnetic Environment on High-Voltage Electrical Substation

    Directory of Open Access Journals (Sweden)

    M. I. Fursanov

    2012-01-01

    Full Text Available Causes of occurrences electrostatic discharges (ESD on high-voltage electric substation were investigated and dependences values ESD’s on parameters interaction structures, humidity of air were found. Experimental research values ESD’s on high-voltage electric substation and in man-made conditions was fulfilled. Uncertainty measurement’s was taken into consideration by research results analyze. Matching with research of other authors was made. Danger ESD’s for electric devises was established.

  17. Mechanisms of pediatric electrical injury. New implications for product safety and injury prevention.

    Science.gov (United States)

    Rabban, J T; Blair, J A; Rosen, C L; Adler, J N; Sheridan, R L

    1997-07-01

    To determine age-specific mechanisms of electrical injury in children, to examine product safety regulation of the major sources of electrical injury hazard, and to assess the adequacy of current prevention strategies. Case series of 144 pediatric and adolescent electrical injuries in patients seen in the specialized burn center and tertiary care hospital between 1970 and 1995, examination of Consumer Product Safety Commission product recall reports for electrical injury hazards between 1973 and 1995, and review of the National Electric Code. Eighty-six cases of electrical injuries resulted from low-voltage (products identified by the Consumer Product Safety Commission to be electrical injury hazards, 119 were appliance cords, extension cords, or holiday stringed light sets. Several products numbered more than 1.5 million units in US household distribution prior to the investigation by the Consumer Product Safety Commission. Household electrical cords are the major electrocution hazard for children younger than 12 years, yet no federal safety mandates exist. Despite voluntary standards, noncompliant manufacturers can introduce vast numbers of unsafe cords onto the US household market every year. Conversion of existing voluntary safety guidelines into federally legislated standards may be the most effective intervention against pediatric electrocutions.

  18. Bilateral upper limb amputations in victims of high tension electrical injuries: Three case studies

    Directory of Open Access Journals (Sweden)

    Cajetan Nwadinigwe

    2015-02-01

    Full Text Available Bilateral upper limb amputations result in severe disability. High voltage electrical injury is a rare cause of such an outcome and injuries often occur as occupational hazards. We present three case reports of accidental high voltage injuries that occurred in a non-occupational setting. Victims were all initially managed at other centres before referral to our hospital and all subsequently had bilateral upper limb amputations. The high cost of treatment, importance of prevention, and need for rehabilitation are highlighted.

  19. Proximity effects of high voltage electric power transmission lines on ...

    African Journals Online (AJOL)

    Yomi

    Zeki Demir. Department of Landscape Architecture, Faculty of Forestry, Düzce University. Konuralp, 81620 Düzce, Turkey. E-mail: zekidemir@duzce.edu.tr. Tel: +90-380-5421136. Fax: +90-380-5421136. Accepted 18 August, 2010. The proximity effects of high voltage electric power transmission lines on Leyland Cypress.

  20. Proximity effects of high voltage electric power transmission lines on ...

    African Journals Online (AJOL)

    The proximity effects of high voltage electric power transmission lines on Leyland Cypress (xCupressocyparis leylandii (Dallim. and A.B. Jacks.) Dallim) and Japanese Privet (Ligustrum japonicum Thunb.) growth were examined in a private nursery located in Sakarya, Turkey. Five transect were randomly chosen in both ...

  1. Integration of Electric Vehicles in Low Voltage Danish Distribution Grids

    DEFF Research Database (Denmark)

    Pillai, Jayakrishnan Radhakrishna; Thøgersen, Paul; Møller, Jan

    2012-01-01

    in the electricity grid operation, a careful examination in the local electricity system is essential. This paper investigates the degree of EV penetration and its key influence on the low voltage distribution grids. Three detailed models of residential grids in Denmark are considered as test cases in this study......Electric Vehicles (EVs) are considered as one of the important components of the future intelligent grids. Their role as energy storages in the electricity grid could provide local sustainable solutions to support more renewable energy. In order to estimate the extent of interaction of EVs...... are reflected as the major technical constraint to the stable operation of the electricity grids for integrating more EVs, when compared to the thermal loading on the cables....

  2. Electric Power High-Voltage Transmission Lines: Design Options, Cost, and Electric and Magnetic Field Levels

    Energy Technology Data Exchange (ETDEWEB)

    Stoffel, J. B. [Argonne National Lab. (ANL), Argonne, IL (United States). Environmental Assessment Division. Electronics and Computing Technologies Division; Pentecost, E. D. [Argonne National Lab. (ANL), Argonne, IL (United States). Environmental Assessment Division; Roman, R. D. [Argonne National Lab. (ANL), Argonne, IL (United States). Environmental Assessment Division; Traczyk, P. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Environmental Assessment Division

    1994-11-01

    The aim of this report is to provide background information about (1) the electric and magnetic fields (EMFs) of high-voltage transmission lines at typical voltages and line configurations and (2) typical transmission line costs to assist preparers and reviewers of the section on alternatives in environmental documents. This report will give the reviewing individual a better appreciation of the factors affecting EMF strengths near high-voltage transmission lines and the approaches that might be used to reduce EMF impacts on humans and other biological species in the vicinity of high-voltage overhead or underground alternating-current (ac) or direct-current (dc) transmission lines.

  3. Electrical actuation of electrically conducting and insulating droplets using ac and dc voltages

    Science.gov (United States)

    Kumari, N.; Bahadur, V.; Garimella, S. V.

    2008-10-01

    Electrical actuation of liquid droplets at the microscale offers promising applications in the fields of microfluidics and lab-on-chip devices. Much prior research has targeted the electrical actuation of electrically conducting liquid droplets using dc voltages (classical electrowetting). Electrical actuation of conducting droplets using ac voltages and the actuation of insulating droplets (using dc or ac voltages) has remained relatively unexplored. This paper utilizes an energy-minimization-based analytical framework to study the electrical actuation of a liquid droplet (electrically conducting or insulating) under ac actuation. It is shown that the electromechanical regimes of classical electrowetting, electrowetting under ac actuation and insulating droplet actuation can be extracted from the generic electromechanical actuation framework, depending on the electrical properties of the droplet, the underlying dielectric layer and the frequency of the actuation voltage. This paper also presents experiments which quantify the influence of the ac frequency and the electrical properties of the droplet on its velocity under electrical actuation. The velocities of droplets moving between two parallel plates under ac actuation are experimentally measured; these velocities are then related to the actuation force on the droplet which is predicted by the electromechanical model developed in this work. It is seen that the droplet velocities are strongly dependent on the frequency of the ac actuation voltage; the cut-off ac frequency, above which the droplet fails to actuate, is experimentally determined and related to the electrical conductivity of the liquid. This paper then analyzes and directly compares the various electromechanical regimes for the actuation of droplets in microfluidic applications.

  4. Direct electrical injury to brachial plexus

    Directory of Open Access Journals (Sweden)

    Maksud Mubarak Devale

    2017-01-01

    Full Text Available Electrical current can cause neurological damage directly or by conversion to thermal energy. However, electrical injury causing isolated brachial plexus injury without cutaneous burns is extremely rare. We present a case of a 17-year-old boy who sustained accidental electrical injury to left upper extremity with no associated entry or exit wounds. Complete motor and sensory loss in upper limb were noted immediately after injury. Subsequently, the patient showed partial recovery in muscles around the shoulder and in ulnar nerve distribution at 6 months. However, there was no improvement in muscles supplied by musculocutaneous, median and radial nerves. On exploration at 6 months after trauma, injury to the infraclavicular plexus was identified. Reconstruction of musculocutaneous, median and radial nerves by means of sural nerve cable grafts was performed. The patient has shown excellent recovery in musculocutaneous nerve function with acceptable recovery of radial nerve function at 1-year post-injury.

  5. High-voltage electrical burn of the genitalia, perineum, and upper extremities: the importance of a multidisciplinary approach.

    Science.gov (United States)

    Tiengo, Cesare; Castagnetti, Marco; Garolla, Andrea; Rigamonti, Waifro; Foresta, Carlo; Azzena, Bruno

    2011-01-01

    High-voltage electrical burns on genitalia and perineal areas are very rare and only sporadic reports are available in the literature with often confusing diagnoses and inconspicuous treatment protocols. Although the surgical treatment of extremities lesions is well established and includes appropriate debridement, temporary wounds coverage, and final adequate soft-tissue reconstruction, management of genital lesions remains controversial and challenging. The authors present a rare case of severe high-voltage electrical injury with involvement of upper extremities and complex lesions localized to the genitalia and perineal region. Treatment required a multidisciplinary approach including the plastic surgery and the urologic and andrologic teams.

  6. Swimming Pool Electrical Injuries: Steps Toward Prevention.

    Science.gov (United States)

    Tashiro, Jun; Burnweit, Cathy A

    2017-01-09

    Electrical injuries in swimming pools are an important pediatric public health concern. We sought to (1) improve our understanding of the clinical presentation and outcomes following and (2) describe the epidemiology of swimming pool electrical injuries in the United States. We reviewed 4 cases of pediatric (public (23.9%) and sports facilities (19.1%). Electrical outlets or receptacles (39.8%) were most commonly implicated, followed by electrical system doors (18.2%), electric wiring systems (17.0%), thermostats (16.3%), hair dryers (4.6%), and radios (4.1%). Pediatric cases represented 48.4% of swimming pool-related electrical injuries reported to NEISS. Electrical injuries occurring in and around swimming pools remain an important source of morbidity and mortality. Although NEISS monitors sentinel events, current efforts at preventing such cases are less than adequate. All electrical outlets near swimming pools should be properly wired with ground fault circuit interrupter devices. Possible approaches to increasing safe electrical device installation are through strengthening public awareness and education of the potential for injury, as well as changes to current inspection regulations.

  7. Electrical tree growth in epoxy resin under DC voltages

    OpenAIRE

    Iddrissu, Ibrahim; Zheng, Hualong; Rowland, Simon

    2016-01-01

    This work investigates electrical tree propagation in a glassy epoxy resin under constant DC voltages of +60 kV and -60 kV, using samples with classical needle-plane electrodes but having small AC trees (henceforth called `initial trees') incepted prior to the DC tests. The characteristics of DC trees propagating from an initial tree is analysed via a sequence of 2-D projections of trees captured using a CCD camera during the test. The experimental results suggest that DC tree growth rate is ...

  8. Thyristor voltage converter in induction electric drives with microprocessor control

    Energy Technology Data Exchange (ETDEWEB)

    Braslavsky, I.; Zuzev, A.; Shilin, S. [Electric Drive Department, Urals State Technical University, Ekaterinburg (Russian Federation)

    1997-12-31

    The paper consists of some results on developed pulse model of thyristor voltage converter which is one of the most mathematically complicated unit of electric drive. The model structure and model parameter calculating method are represented. The application of the model allows to analyse stability in `locally` by the linear pulse system theory methods with talking into consideration quantise processes within the converter. Such application provides the obtaining higher accurate results comparing with the non-linear system theory approximate methods. Logarithmic frequency characteristics are used to analyse converter dynamic features and they are represented too. (orig.) 4 refs.

  9. Effects of load voltage on voltage breakdown modes of electrical exploding aluminum wires in air

    Science.gov (United States)

    Wu, Jian; Li, Xingwen; Yang, Zefeng; Wang, Kun; Chao, Youchuang; Shi, Zongqian; Jia, Shenli; Qiu, Aici

    2015-06-01

    The effects of the load voltage on the breakdown modes are investigated in exploding aluminum wires driven by a 1 kA, 0.1 kA/ns pulsed current in air. From laser probing images taken by laser shadowgraphy, schlieren imaging, and interferometry, the position of the shockwave front, the plasma channel, and the wire core edge of the exploding product can be determined. The breakdown mode makes a transition from the internal mode, which involves breakdown inside the wire core, to the shunting mode, which involves breakdown in the compressed air, with decreasing charging voltage. The breakdown electrical field for a gaseous aluminum wire core of nearly solid density is estimated to be more than 20 kV/cm, while the value for gaseous aluminum of approximately 0.2% solid density decreases to 15-20 kV/cm. The breakdown field in shunting mode is less than 20 kV/cm and is strongly affected by the vaporized aluminum, the desorbed gas, and the electrons emitted from the wire core during the current pause. Ohmic heating during voltage collapses will induce further energy deposition in the current channel and thus will result in different expansion speeds for both the wire core and the shockwave front in the different modes.

  10. Generator voltage stabilisation for series-hybrid electric vehicles.

    Science.gov (United States)

    Stewart, P; Gladwin, D; Stewart, J; Cowley, R

    2008-04-01

    This paper presents a controller for use in speed control of an internal combustion engine for series-hybrid electric vehicle applications. Particular reference is made to the stability of the rectified DC link voltage under load disturbance. In the system under consideration, the primary power source is a four-cylinder normally aspirated gasoline internal combustion engine, which is mechanically coupled to a three-phase permanent magnet AC generator. The generated AC voltage is subsequently rectified to supply a lead-acid battery, and permanent magnet traction motors via three-phase full bridge power electronic inverters. Two complementary performance objectives exist. Firstly to maintain the internal combustion engine at its optimal operating point, and secondly to supply a stable 42 V supply to the traction drive inverters. Achievement of these goals minimises the transient energy storage requirements at the DC link, with a consequent reduction in both weight and cost. These objectives imply constant velocity operation of the internal combustion engine under external load disturbances and changes in both operating conditions and vehicle speed set-points. An electronically operated throttle allows closed loop engine velocity control. System time delays and nonlinearities render closed loop control design extremely problematic. A model-based controller is designed and shown to be effective in controlling the DC link voltage, resulting in the well-conditioned operation of the hybrid vehicle.

  11. Electric and magnetic field measurements in a high voltage center.

    Science.gov (United States)

    Safigianni, Anastasia S; Spyridopoulos, Anastasios I; Kanas, Vasilis L

    2012-01-01

    This paper investigates the electric and magnetic fields inside a large high voltage center constituted both of 400/150 and 150/20 kV substation areas. Results of previous field measurements and calculations in substations, made by the authors of this paper or other researchers, are presented first. The basic data distinguishing the examined center from previously examined substations follow. The main results of the field measurements in the areas of the above-mentioned center are presented in relevant diagrams. General conclusions arising from the comparison of the measured field values with relevant reference levels in force for safe public and occupational exposure as well as with the results of previous research are finally given.

  12. Voltage-Gated Calcium Channel Antagonists and Traumatic Brain Injury

    Directory of Open Access Journals (Sweden)

    Bruce Lyeth

    2013-06-01

    Full Text Available Traumatic brain injury (TBI is a leading cause of death and disability in the United States. Despite more than 30 years of research, no pharmacological agents have been identified that improve neurological function following TBI. However, several lines of research described in this review provide support for further development of voltage gated calcium channel (VGCC antagonists as potential therapeutic agents. Following TBI, neurons and astrocytes experience a rapid and sometimes enduring increase in intracellular calcium ([Ca2+]i. These fluxes in [Ca2+]i drive not only apoptotic and necrotic cell death, but also can lead to long-term cell dysfunction in surviving cells. In a limited number of in vitro experiments, both L-type and N-type VGCC antagonists successfully reduced calcium loads as well as neuronal and astrocytic cell death following mechanical injury. In rodent models of TBI, administration of VGCC antagonists reduced cell death and improved cognitive function. It is clear that there is a critical need to find effective therapeutics and rational drug delivery strategies for the management and treatment of TBI, and we believe that further investigation of VGCC antagonists should be pursued before ruling out the possibility of successful translation to the clinic.

  13. Returning to Work After Electrical Injuries

    DEFF Research Database (Denmark)

    Stergiou-Kita, M.; Mansfield, E.; Bayley, M.

    2014-01-01

    injuries to advocate on their behalf. Immediate and persistent physical, cognitive, psychosocial, and support factors can affect individuals' abilities to successfully return to work after an electrical injury. Specialized services and advocacy were viewed as beneficial to successful return to work....... were conducted with individuals who experienced an electrical injury at the workplace. Participants were recruited from specialized burns rehabilitation programs in Ontario, Canada. Interviews were transcribed verbatim and thematic analysis used to analyze the qualitative interviews. Data regarding...... workers' demographics, injury events, and occupational categories were also gathered to characterize the sample. Participants identified three distinct categories of challenges: 1) physical, cognitive, and psychosocial impairments and their effects on their work performance; 2) feelings of guilt, blame...

  14. Bony ankylosis following thermal and electrical injury

    Energy Technology Data Exchange (ETDEWEB)

    Balen, P.F.; Helms, C.A. [Dept. of Radiology, Duke University Medical Center, Durham, NC (United States)

    2001-07-01

    Objective. Bony ankylosis has been described following trauma, paralysis, psoriasis, Reiter's syndrome, ankylosing spondylitis, juvenile chronic arthritis and rheumatoid arthritis. Reports of bony ankylosis following thermal and electrical injury are limited.Design and patients. Thirteen cases of burn-related joint ankylosis in four patients are presented.Conclusion. Patients with burns from thermal or electrical injury may develop bony ankylosis among other radiographic manifestations. This bony ankylosis may result either from bridging extra-articular heterotopic ossification with preservation of the underlying joint or from intra-articular fusion due to joint destruction. (orig.)

  15. THE EFFECT OF LIGHTNING ON HIGH VOLTAGE ELECTRICAL SUBSTATIONS’ LOW VOLTAGE SYSTEMS

    Directory of Open Access Journals (Sweden)

    M. I. Fursanov

    2016-01-01

    Full Text Available The article presents the results of studies of the effects of lightning on low voltage systems of high voltage electrical substations with outdoor switchgears of 110 kV. The topicality of research is associated with a wide spreading of such substations as well as with a high reliability requirements of their work and, also, with their widespread distribution and high probability of lightning strikes to the substation or around it. The highest probable and the most dangerous effects of lightning on low voltage systems of a substation are determined on the basis of critical review and special literature analysis and, also, of systematization of practical information that had been collected during the survey of operating substations. Adequate physical models were developed for the list of hazardous effects based on physical processes of lightning. A model of each effect was studied on the basis of the sensitivity theory. The accuracy and adequacy of the models were verified by means of comparison of calculation results for the models under investigation with the results of calculations fulfilled in accordance with specialized programs, as well as from practical or theoretical data obtained by other authors. The factors that had been included in the models were studied and were defined in accordance with their nature (natural or artificial, the range of possible values in a substation was determined; the coefficients of elasticity were calculated. The obtained results enable to ascertain the contribution of the factor in the effect of lightning and the ability to control the factor. The relationship between the factors and the effects of lightning are shown as graphs. For practical application the information, obtained as the result of the research, was organized in the form of checklists that can be applied when collecting baseline information to develop the lightning protection of the substation, to examine the existing lightning protection, to

  16. Advanced electric propulsion system concept for electric vehicles. Addendum 1: Voltage considerations

    Science.gov (United States)

    Raynard, A. E.; Forbes, F. E.

    1980-01-01

    The two electric vehicle propulsion systems that best met cost and performance goals were examined to assess the effect of battery pack voltage on system performance and cost. A voltage range of 54 to 540 V was considered for a typical battery pack capacity of 24 k W-hr. The highest battery specific energy (W-hr/kg) and the lowest cost ($/kW-hr) were obtained at the minimum voltage level. The flywheel system traction motor is a dc, mechanically commutated with shunt field control, and due to the flywheel the traction motor and the battery are not subject to extreme peaks of power demand. The basic system uses a permanent-magnet motor with electronic commutation supplied by an ac power control unit. In both systems battery cost were the major factor in system voltage selection, and a battery pack with the minimum voltage of 54 V produced the lowest life-cycle cost. The minimum life-cycle cost for the basic system with lead-acid batteries was $0.057/km and for the flywheel system was $0.037/km.

  17. Impact of plug-in electric vehicles on voltage unbalance in ...

    African Journals Online (AJOL)

    Additionally, the voltage unbalance due to PEVs discharging and other types of distribution generator such as solar photovoltaic and wind turbines are investigated. Finally, some voltage unbalance mitigation techniques are summarized. Keywords: Distribution Network, Electric Vehicle, G2V, V2G, Voltage Unbalance ...

  18. Impact of plug-in electric vehicles on voltage unbalance in ...

    African Journals Online (AJOL)

    DR OKE

    In this work, impact of plug-in electric vehicles on voltage imbalance in distribution system is presented. In G2V as well as V2G modes, the voltage unbalance .... BEVs use electric motors and motor controllers instead of internal combustion engines (ICEs) for propulsion. Today's BEVs can travel at least 60 to 160 miles on a ...

  19. Peripapillary retinal thermal coagulation following electrical injury

    Directory of Open Access Journals (Sweden)

    Manjari Tandon

    2013-01-01

    Full Text Available In this study, we have presented the case report of a 20 year old boy who suffered an electric injury shock, following which he showed peripapillary retinal opacification and increased retinal thickening that subsequently progressed to retinal atrophy. The fluorescein angiogram revealed normal retinal circulation, thus indicating thermal damage to retina without any compromise to retinal circulation.

  20. Self-Healable Electrical Insulation for High Voltage Applications

    Science.gov (United States)

    Williams, Tiffany S.

    2017-01-01

    Polymeric aircraft electrical insulation normally degrades by partial discharge with increasing voltage, which causes excessive localized Joule heating in the material and ultimately leads to dielectric failure of the insulator through thermal breakdown. Developing self-healing insulation could be a viable option to mitigate permanent mechanical degradation, thus increasing the longevity of the insulation. Instead of relying on catalyst and monomer-filled microcapsules to crack, flow, and cure at the damaged sites described in well-published mechanisms, establishment of ionic crosslinks could allow for multiple healing events to occur with the added benefit of achieving full recovery strength under certain thermal environments. This could be possible if the operating temperature of the insulator is the same as or close to the temperature where ionic crosslinks are formed. Surlyn, a commercial material with ionic crosslinks, was investigated as a candidate self-healing insulator based off prior demonstrations of self-healing behavior. Thin films of varying thicknesses were investigated and the effects of thickness on the dielectric strength were evaluated and compared to representative polymer insulators. The effects of thermal conditioning on the recovery strength and healing were observed as a function of time following dielectric breakdown. Moisture absorption was also studied to determine if moisture absorption rates in Surlyn were lower than that of common polyimides.

  1. Motor neuron disease after electric injury

    Science.gov (United States)

    Jafari, H; Couratier, P; Camu, W

    2001-01-01

    The occurrence of motor neuron disease after electrical injury in six patients is reported and compared with patients from the literature. The patients were five men with spinal onset and one woman with bulbar motor neuron disease after electric shock. Two patients were struck by lightning and four by industrial electric shock. For all six of them, the disease started at the site of the electrical trauma. The mean delay for onset of motor neuron disease was 44 months. In four of the spinal patients the disease progressed slowly with mild handicap after several years. For the fifth patient, improvement was noted progressively. The patient with bulbar disease died 26 months after onset. A link between electric shock and motor neuron disease is likely, given the homogenous profile of the patients both in the five spinal cases presented here and in the literature. Bulbar onset has not been reported to date. However, in this patient the long delay between the electrical injury and motor neuron disease, together with the rapid evolution may suggest a chance association.

 PMID:11459909

  2. High voltage bus and auxiliary heater control system for an electric or hybrid vehicle

    Science.gov (United States)

    Murty, Balarama Vempaty

    2000-01-01

    A control system for an electric or hybrid electric vehicle includes a vehicle system controller and a control circuit having an electric immersion heater. The heater is electrically connected to the vehicle's high voltage bus and is thermally coupled to a coolant loop containing a heater core for the vehicle's climate control system. The system controller responds to cabin heat requests from the climate control system by generating a pulse width modulated signal that is used by the control circuit to operate the heater at a duty cycle appropriate for the amount of cabin heating requested. The control system also uses the heater to dissipate excess energy produced by an auxiliary power unit and to provide electric braking when regenerative braking is not desirable and manual braking is not necessary. The control system further utilizes the heater to provide a safe discharge of a bank of energy storage capacitors following disconnection of the battery or one of the high voltage connectors used to transmit high voltage operating power to the various vehicle systems. The control circuit includes a high voltage clamping circuit that monitors the voltage on the bus and operates the heater to clamp down the bus voltage when it exceeds a pre-selected maximum voltage. The control system can also be used to phase in operation of the heater when the bus voltage exceeds a lower threshold voltage and can be used to phase out the auxiliary power unit charging and regenerative braking when the battery becomes fully charged.

  3. Guidelines for Distribution System Operators on Reactive Power Provision by Electric Vehicles in Low Voltage Grids

    DEFF Research Database (Denmark)

    Zecchino, Antonio; Marinelli, Mattia; Træholt, Chresten

    2017-01-01

    The increasing success of electric vehicles is bringing new technical challenges to power system operators. This work intends to provide guidelines for distribution system operators in terms of reactive power requirements when evaluating and authorizing electric vehicles supply equipment with fast...... the amount of reactive power that an individual electric vehicle is expected to provide when connected to a low voltage feeder, in order to benefit of the desired voltage rise effect in comparison to the case of unitary power factor....

  4. Analysis of Voltage Support by Electric Vehicles and Photovoltaic in a Real Danish Low Voltage Network

    DEFF Research Database (Denmark)

    Knezovic, Katarina; Marinelli, Mattia; Juul Møller, René

    2014-01-01

    With conventional generating units being replaced by renewable sources which are not required to provide same high level of ancillary services, there is an increasing need for additional resources to achieve certain standards regarding frequency and voltage. This paper investigates the potential ...... with addressing the issues regarding voltage control at the expense of increased loading. Analysed real Danish low voltage network has been modelled in Matlab SimPowerSystems and is based on consumption and PV production data measured individually for number of households....

  5. Review of the Dynamics of Coalescence and Demulsification by High-Voltage Pulsed Electric Fields

    Directory of Open Access Journals (Sweden)

    Ye Peng

    2016-01-01

    Full Text Available The coalescence of droplets in oil can be implemented rapidly by high-voltage pulse electric field, which is an effective demulsification dehydration technological method. At present, it is widely believed that the main reason of pulse electric field promoting droplets coalescence is the dipole coalescence and oscillation coalescence in pulse electric field, and the optimal coalescence pulse electric field parameters exist. Around the above content, the dynamics of high-voltage pulse electric field promoting the coalescence of emulsified droplets is studied by researchers domestically and abroad. By review, the progress of high-voltage pulse electric field demulsification technology can get a better understanding, which has an effect of throwing a sprat to catch a whale on promoting the industrial application.

  6. A novel series connected batteries state of high voltage safety monitor system for electric vehicle application.

    Science.gov (United States)

    Jiaxi, Qiang; Lin, Yang; Jianhui, He; Qisheng, Zhou

    2013-01-01

    Batteries, as the main or assistant power source of EV (Electric Vehicle), are usually connected in series with high voltage to improve the drivability and energy efficiency. Today, more and more batteries are connected in series with high voltage, if there is any fault in high voltage system (HVS), the consequence is serious and dangerous. Therefore, it is necessary to monitor the electric parameters of HVS to ensure the high voltage safety and protect personal safety. In this study, a high voltage safety monitor system is developed to solve this critical issue. Four key electric parameters including precharge, contact resistance, insulation resistance, and remaining capacity are monitored and analyzed based on the equivalent models presented in this study. The high voltage safety controller which integrates the equivalent models and control strategy is developed. By the help of hardware-in-loop system, the equivalent models integrated in the high voltage safety controller are validated, and the online electric parameters monitor strategy is analyzed and discussed. The test results indicate that the high voltage safety monitor system designed in this paper is suitable for EV application.

  7. Multi-objective optimization control of plug-in electric vehicles in low voltage distribution networks

    DEFF Research Database (Denmark)

    García-Villalobos, J.; Zamora, I.; Knezovic, Katarina

    2016-01-01

    The massive introduction of plug-in electric vehicles (PEVs) into low voltage (LV) distribution networks will lead to several problems, such as: increase of energy losses, decrease of distribution transformer lifetime, lines and transformer overload issues, voltage drops and unbalances. In this c...

  8. A Novel Series Connected Batteries State of High Voltage Safety Monitor System for Electric Vehicle Application

    Directory of Open Access Journals (Sweden)

    Qiang Jiaxi

    2013-01-01

    Full Text Available Batteries, as the main or assistant power source of EV (Electric Vehicle, are usually connected in series with high voltage to improve the drivability and energy efficiency. Today, more and more batteries are connected in series with high voltage, if there is any fault in high voltage system (HVS, the consequence is serious and dangerous. Therefore, it is necessary to monitor the electric parameters of HVS to ensure the high voltage safety and protect personal safety. In this study, a high voltage safety monitor system is developed to solve this critical issue. Four key electric parameters including precharge, contact resistance, insulation resistance, and remaining capacity are monitored and analyzed based on the equivalent models presented in this study. The high voltage safety controller which integrates the equivalent models and control strategy is developed. By the help of hardware-in-loop system, the equivalent models integrated in the high voltage safety controller are validated, and the online electric parameters monitor strategy is analyzed and discussed. The test results indicate that the high voltage safety monitor system designed in this paper is suitable for EV application.

  9. Investigation of Voltage Unbalance Problems In Electric Arc Furnace Operation Model

    Directory of Open Access Journals (Sweden)

    Yacine DJEGHADER

    2013-06-01

    Full Text Available In modern steel industry, Electric Arc Furnaces are widely used for iron and scarp melting. The operation of electric arc furnace causes many power quality problems such as harmonics, unbalanced voltage and flicker. The factors that affect Electric arc furnace operation are the melting or refining materials, melting stage, electrodes position (arc length, electrode arm control and short circuit power of the feeder, so, arc voltages, current and power are defined as a nonlinear function of arc length. This study focuses on investigation of unbalanced voltage due to Electrics Arc Furnace operation mode. The simulation results show the major problem of unbalanced voltage affecting secondary of furnace transformer is caused by the different continues movement of electrodes.

  10. Study on Earthquake Response of High Voltage Electrical Equipment Coupling System with Flexible Busbar

    Science.gov (United States)

    Liu, Chuncheng; Qu, Da; Wang, Chongyang; Lv, Chunlei; Li, Guoqiang

    2017-12-01

    With the rapid development of technology and society, all walks of life in China are becoming more and more dependent on power systems. When earthquake occurs, the electrical equipment of substation is prone to damage because of its own structural features, top-heavy, and brittleness of main body. At the same time, due to the complex coupling of the soft electrical connection of substation electrical equipment, the negative impact can not be estimated. In this paper, the finite element model of the coupling system of the single unit of high voltage electrical equipment with the connecting soft bus is established and the seismic response is analysed. The results showed that there is a significant difference between the simple analysis for the seismic response of electrical equipment monomer and the analytical results of electrical equipment systems, and the impact on different electrical equipment is different. It lays a foundation for the future development of seismic performance analysis of extra high voltage electrical equipment.

  11. Electrical Burn Causing a Unique Pattern of Neurological Injury

    Directory of Open Access Journals (Sweden)

    Nathan R. Schaefer, BExSc, MBBS (Hons

    2015-04-01

    Full Text Available Summary: Neurological involvement is not uncommon in patients who sustain electrical injury. The exact mechanism of nervous system damage following electrical trauma is not fully understood. The gamut of possible neurologic manifestations following electrical injury is diverse. This case report describes a young man with a unique pattern of neurological injury following an electrical burn. The combination of brachial plexopathy, partial Horner’s syndrome, and phrenic nerve palsy secondary to electrical injury has not been previously described in the literature.

  12. Investigations of the quality of hospital electric power supply and the tolerance of medical electric devices to voltage dips.

    Science.gov (United States)

    Hanada, Eisuke; Itoga, Shuuya; Takano, Kyoko; Kudou, Takato

    2007-06-01

    Medical devices driven by electric power have come to be commonly used in hospitals, and rapid changes of voltage or current can easily cause them to fail. A stable and high quality power supply is indispensable in order to maintain safety in the modern clinical setting. Therefore, we investigated the quality of the power supply in a hospital and determined the tolerance of 13 pieces of medical equipment to voltage dips. The results showed little distortion of the voltage wave. However, we found an approximately 7% momentary voltage dip caused by lightening and other problems, such as 2 to 5% periodic drops in voltage and voltage wave distortions caused by incorrect grounding. In a tolerance test, the settings of some medical devices were changed at the time of automatic reboot after a disturbance. For another device, trend information was initialized.

  13. High-voltage electrical stimulation improves nerve regeneration after sciatic crush injury Estimulação elétrica de alta voltagem favorece a regeneração nervosa após compressão do nervo isquiático

    Directory of Open Access Journals (Sweden)

    Rosana M. Teodori

    2011-08-01

    Full Text Available BACKGROUND: Peripheral nerve injury causes prolonged functional limitation being a clinical challenge to identify resources that accelerates its recovery. OBJECTIVES: To investigate the effect of high-voltage electrical stimulation (HVES on the morphometric and functional characteristics of the regenerated nerve after crush injury in rats. METHODS: Twenty Wistar rats were randomly allocated into 4 groups: Control (CON - without injury and without HVES; Denervated (D - sciatic nerve crush only; Denervated + HVES - sciatic nerve crush and HVES; SHAM - without injury but HVES. The HVES and SHAM groups were stimulated (100 Hz; minimum voltage of 100 V, 20 μs, 100 μs interpulse interval for 30 min/day, 5 days/week. The sciatic functional index (SFI was evaluated before the injury and at the 7th, 14th and 21st postoperatory (PO days. Neural components and the area density of connective tissue, blood vessels and macrophages were analyzed. RESULTS: Axonal diameter was higher on the HVES than on D group, reaching almost 80% above the control values after 21 days (pCONTEXTUALIZAÇÃO: Lesões nervosas periféricas provocam limitação funcional prolongada, sendo um desafio para a clínica identificar recursos que acelerem sua recuperação. OBJETIVOS: Investigar a influência da estimulação elétrica de alta voltagem (EEAV sobre a morfologia e a função do nervo regenerado após esmagamento em ratos. MÉTODOS: Vinte ratos Wistar foram divididos nos grupos: controle (CON - sem lesão e sem EEAV; desnervado (D - esmagamento do nervo isquiático; desnervado + EEAV (EEAV - esmagamento do nervo e EEAV; SHAM - sem lesão, porém submetido à EEAV. Os grupos EEAV e SHAM foram estimulados (100 Hz, tensão mínima de 100 V; 20 μs e 100 μs interpulso 30 min/dia, 5 dias/semana. O índice funcional do ciático (IFC foi avaliado antes da lesão, nos 7º, 14º e 21º dias pós-operatório (PO. Componentes neurais, densidade de área de tecido conjuntivo, de

  14. MR imaging findings of high-voltage electrical burns in the upper extremities: correlation with angiographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gyung Kyu; Kang, Ik Won; Hwang, Dae Hyun; Min, Seon Jung; Han, You Mi (Dept. of Radiology, Hallym Univ. College of Medicine, Hangang Sacred Heart Hospital, Seoul (Korea, Republic of)); Suh, Kyung Jin (Dept. of Radiology, Dongguk Univ. College of Medicine, Gyeongju Hospital, Gyeongju (Korea, Republic of)), email: kyungjin.suh@gmail.com; Choi, Min Ho (Dept. of Internal Medicine, Hallym Univ. College of Medicine, Hangang Sacred Heart Hospital, Seoul (Korea, Republic of))

    2011-02-15

    Background: A high-voltage electrical burn is often associated with deep muscle injuries. Hidden, undetected deep muscle injuries have a tendency for progressive tissue necrosis, and this can lead to major amputations or sepsis. MRI has excellent soft tissue contrast and it may aid in differentiating the areas of viable deep muscle from the areas of non-viable deep muscle. Purpose: To describe the MR imaging findings of a high-voltage electrical burn in the upper extremity with emphasis on the usefulness of the gadolinium-enhanced MRI and to compare the MR imaging findings with angiography. Material and Methods: We retrospectively reviewed the imaging studies of six patients with high-voltage electrical burns who underwent both MRI and angiography at the burn center of our hospital from January 2005 to December 2009. The imaging features were evaluated for the involved locations, the MR signal intensity of the affected muscles, the MR enhancement pattern, the involved arteries and the angiographic findings (classified as normal, sluggish flow, stenosis or occlusion) of the angiography of the upper extremity. We assessed the relationship between the MR imaging findings and the angiographic findings. Results: The signal intensities of affected muscles were isointense or of slightly high signal intensity as compared with the adjacent unaffected skeletal muscle on the T1-weighted MR images. Affected muscles showed heterogenous high signal intensity relative to the adjacent unaffected skeletal muscle on the T2- weighted images. The gadolinium-enhanced T1-weighted images showed diffuse inhomogeneous enhancement or peripheral rim enhancement of the affected muscles. The angiographic findings of the arterial injuries showed complete occlusion in three patients, severe stenosis in two patients and sluggish flow in one patient. Of these, the five patients with complete occlusion or severe stenosis on angiography showed non-perfused and non-viable areas of edematous muscle on

  15. Insulation co-ordination in high-voltage electric power systems

    CERN Document Server

    Diesendorf, W

    2015-01-01

    Insulation Co-ordination in High-Voltage Electric Power Systems deals with the methods of insulation needed in different circumstances. The book covers topics such as overvoltages and lightning surges; disruptive discharge and withstand voltages; self-restoring and non-self-restoring insulation; lightning overvoltages on transmission lines; and the attenuation and distortion of lightning surges. Also covered in the book are topics such as the switching surge designs of transmission lines, as well as the insulation coordination of high-voltage stations. The text is recommended for electrical en

  16. Functional electrical stimulation and spinal cord injury.

    Science.gov (United States)

    Ho, Chester H; Triolo, Ronald J; Elias, Anastasia L; Kilgore, Kevin L; DiMarco, Anthony F; Bogie, Kath; Vette, Albert H; Audu, Musa L; Kobetic, Rudi; Chang, Sarah R; Chan, K Ming; Dukelow, Sean; Bourbeau, Dennis J; Brose, Steven W; Gustafson, Kenneth J; Kiss, Zelma H T; Mushahwar, Vivian K

    2014-08-01

    Spinal cord injuries (SCI) can disrupt communications between the brain and the body, resulting in loss of control over otherwise intact neuromuscular systems. Functional electrical stimulation (FES) of the central and peripheral nervous system can use these intact neuromuscular systems to provide therapeutic exercise options to allow functional restoration and to manage medical complications following SCI. The use of FES for the restoration of muscular and organ functions may significantly decrease the morbidity and mortality following SCI. Many FES devices are commercially available and should be considered as part of the lifelong rehabilitation care plan for all eligible persons with SCI. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Guidelines for Distribution System Operators on Reactive Power Provision by Electric Vehicles in Low Voltage Grids

    DEFF Research Database (Denmark)

    Zecchino, Antonio; Marinelli, Mattia; Træholt, Chresten

    2017-01-01

    The increasing success of electric vehicles is bringing new technical challenges to power system operators. This work intends to provide guidelines for distribution system operators in terms of reactive power requirements when evaluating and authorizing electric vehicles supply equipment with fast...... the amount of reactive power that an individual electric vehicle is expected to provide when connected to a low voltage feeder, in order to benefit of the desired voltage rise effect in comparison to the case of unitary power factor....... charging capability in existing low voltage distribution feeders. The aim is to prevent the voltage to exceed the permitted values when charging at high power, by exploiting the effect of the reactive power. The proposed guidelines for distribution system operators are reported in a matrix, which indicates...

  18. [Changes of platelet rheological behavior and the interventional effects of ulinastatin in rats with high-voltage electrical burns].

    Science.gov (United States)

    Zhang, Q F; Li, Y; Feng, J K; Xu, Y F; Tu, L L

    2017-12-20

    Objective: To explore the influence of high-voltage electrical burns on the number of platelet aggregation, β-thromboglobulin (β-TG) and platelet factor 4 (PF-4) and the interventional effects of ulinastatin in rats with high-voltage electrical burns. Methods: A total of 240 Sprague-Dawley rats were divided into sham injury (SI) group, simple electrical burn (SEB) group, normal saline (NS) group, and ulinastatin (UTI) group according to the random number table, with 60 rats in each group. The electrical current was applied to the outside proximal part of left forelimb of rats and exited from the outside proximal part of right hind limb of rats. Rats in groups SEB, NS, and UTI were inflicted with high-voltage electrical burn wounds of 1 cm×1 cm at current entrances and exits, with the voltage regulator and experimental transformer. Rats in group SI were sham injured through connecting the same equipments without electricity. At 2 min post injury, rats in group NS were intraperitoneally injected with 2 mL/kg NS, and rats in group UTI were intraperitoneally injected with 2×10(4) U/kg UTI of 10 g/L. At 15 min before injury and 5 min, 1 h, 2 h, 4 h, 8 h post injury, 10 rats in each group were selected to collect 5-7 mL blood of heart respectively. Blood of 0.05 mL were collected to make fresh blood smear for observing the number of platelet aggregation, and serum were separated from the remaining blood to determine content of β-TG and PF-4 with enzyme-linked immunosorbent assay. Data were processed with analysis of factorial design of variance, student-Newman-Keuls test, Kruskal-Wallis H test, Wilcoxon rank sum test, and Bonferroni correction. Results: (1) At 15 min before injury, the numbers of platelet aggregation of rats were close among groups SI, SEB, NS and UTI (5.9±1.2, 5.8±1.2, 5.9±1.3, 5.9±1.1, respectively, with P values above 0.05). At 5 min, 1 h, 2 h, 4 h, 8 h post injury, the numbers of platelet aggregation of rats in group SEB were 57.2±16.3, 59

  19. Frequency-Control Reserves and Voltage Support from Electric Vehicles

    DEFF Research Database (Denmark)

    Pillai, Jayakrishnan Radhakrishna; Bak-Jensen, Birgitte

    2013-01-01

    -fuelled generators to supply future grid support functions. The quick start and fast response characteristics of battery storages enable the electric vehicles to provide most of the power system auxiliary tasks. This chapter discusses key ancillary services that could be supplied by electric vehicles to maintain......The increasing penetration of variable wind power generation units and electricity consumption in power systems demands additional ancillary services for its reliable operation. The battery storages of electric vehicles are one of the substitute solutions for replacing conventional fossil...... the system balance in power systems with high volumes of wind power generation. To analyse the applications and performance of electric vehicles in supplying active power balancing services, the case studies simulated in wind-power-dominated Danish power systems are also presented....

  20. Analysis of harmonics in the power supply networks of electric welding equipment of alternating voltage

    Directory of Open Access Journals (Sweden)

    Василь Ількович Гудим

    2015-11-01

    Full Text Available Electric arc welding is widely used in construction and engineering for rigid connections of metal elements. Substantial nonlinearity of dynamic voltage-current characteristics of electric arcs in such equipment is a source of distortion in current and voltage sinusoids at the points of other electric receivers parallel joints. The voltage fluctuations from the nominal value result in changing luminous flux of bulbs, while current higher harmonics result in additional losses in electric motors. However, the problem of electric welding equipment influence on power lines wasn’t paid proper attention to. Therefore, this work is to research electric arc equipment influence on power lines in order to find out the values and the spectrum of higher harmonics, and the prevailing amplitudes dynamics of change. In this paper the results of experimental researches of harmonics spectrum in electrical circuits of electric arc welding machine of alternating voltage that it generates during the technological process and the main energy parameters, that influence negatively on the power supply networks of 0,4/0,23 kV. Analyzing the results of the measurements we come to the conclusion that if the load factor is about 35% the power coefficient of the welding machine is 0,46, that is rather low. Such a result is economically disadvantageous since high reactive power results in a significant increase of active power losses in the elements of power supply. That’s why reactive power compensation as well as higher harmonics filtration are necessitated

  1. Electrical engineering unit for the reactive power control of the load bus at the voltage instability

    Science.gov (United States)

    Kotenev, A. V.; Kotenev, V. I.; Kochetkov, V. V.; Elkin, D. A.

    2018-01-01

    For the purpose of reactive power control error reduction and decrease of the voltage sags in the electric power system caused by the asynchronous motors started the mathematical model of the load bus was developed. The model was built up of the sub-models of the following elements: a transformer, a transmission line, a synchronous and an asynchronous loads and a capacitor bank load, and represents the automatic reactive power control system taking into account electromagnetic processes of the asynchronous motors started and reactive power changing of the electric power system elements caused by the voltage fluctuation. The active power/time and reactive power/time characteristics based on the recommended procedure of the equivalent electric circuit parameters calculation were obtained. The derived automatic reactive power control system was shown to eliminate the voltage sags in the electric power system caused by the asynchronous motors started.

  2. THE ENERGY SPECTRA OF RANDOM PROCESSES OF TRACTION VOLTAGES AND CURRENTS OF ELECTRIC TRANSPORT

    Directory of Open Access Journals (Sweden)

    M. O. Kostin

    2015-12-01

    Full Text Available Spectral analysis of traction voltages and currents are the basis for assessing energy electromagnetic processes in systems of electric traction, in particular, DC. The latter is due to the fact that the DC system is not in consequence of nonstationary random character of change of traction voltage and current. Nonperiodic stochastic nature of the change of voltage and current calls for study of their spectral composition using probabilistic methods based on spectral correlation theory of random processes. The theoretical assumptions and the relations of connection of the energy spectrum of a random process with his correlating function are set out. The results of the numerical calculations of the spectra of traction voltages and currents actually operating electrical subsystems transport are given; they are: feeder voltage at the traction substation; currents in modes of traction and recuperation of electric locomotives in accordance with DE 1 and VL 8; the voltage on the current collector of the city tram. It is established that energy spectra of random processes traction and recuperative voltages and currents are probabilistic in nature, depending on technological factors of the system, and the energy of the random process is numerically greater in traction mode than in the regenerative braking modes

  3. Electric field analysis of extra high voltage (EHV) underground cables using finite element method

    DEFF Research Database (Denmark)

    Kumar, Mantosh; Bhaskar, Mahajan Sagar; Padmanaban, Sanjeevikumar

    2017-01-01

    Transmission and Distribution of electric power through underground cables is a viable alternative to overhead lines, particularly in residential or highly populated areas. The electrical stresses are consequences of regular voltages and over voltages and the thermal stresses are related to heat...... produced inside the conductor due to flow of high rated current which is the main factors that affect its reliability. The performance of these underground power cables is important for proper operation of the power system. Long-term problems with them are related to the degradation of polymer materials...... used for the insulator due electrical, thermal or environmental stress. Most of these problems are related to the electric field stress on the insulation of the underground cables. The objective of the electric field analysis by using different numerical techniques is to find electric field stress...

  4. Variable Bus Voltage Modeling for Series Hybrid Electric Vehicle Simulation

    OpenAIRE

    Merkle, Matthew Alan

    1997-01-01

    A growing dependence on foreign oil, along with a heightened concern over the environmental impact of personal transportation, had led the U. S. government to investigate and sponsor research into advanced transportation concepts. One of these future technologies is the hybrid electric vehicle (HEV), typically featuring both an internal combustion engine and an electric motor, with the goal of producing fewer emissions while obtaining superior fuel economy. While vehicles such as the Virg...

  5. Diffusion voltage in polymer light emitting diodes measured with electric field induced second harmonic generation

    Energy Technology Data Exchange (ETDEWEB)

    Kristensen, P.K.; Rafaelsen, J.; Pedersen, T.G.; Pedersen, K. [Department of Physics and Nanotechnology, Aalborg University, Pontoppidanstraede 103, 9220 Aalborg East (Denmark)

    2005-12-01

    We apply electric field induced second harmonic (EFISH) to polymer light emitting diodes (PLEDs) and demonstrate the ability to determine the diffusion voltage in PLED devices. The EFISH signal is proportional to the square of the effective field, which is the sum of the diffusion voltage and the applied voltage. By minimizing the EFISH-signal as a function of the applied voltage, the diffusion voltage is determined by measuring the applied voltage that cancels out the diffusion voltage. The PLEDs are fabricated with indium tin oxide (ITO) as the hole injecting contact and two different electron injecting contacts, namely aluminum and calcium. The diffusion voltage originates from the rearranged charges caused by the difference in Fermi levels in the materials in the PLEDs. Different contacts will thus cause different diffusion voltages. We demonstrate here that the EFISH signal is proportional to the square of the effective field in both reverse and forward bias, and discuss the dependence on contact materials. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Differential effect of brief electrical stimulation on voltage-gated potassium channels.

    Science.gov (United States)

    Cameron, Morven A; Al Abed, Amr; Buskila, Yossi; Dokos, Socrates; Lovell, Nigel H; Morley, John W

    2017-05-01

    Electrical stimulation of neuronal tissue is a promising strategy to treat a variety of neurological disorders. The mechanism of neuronal activation by external electrical stimulation is governed by voltage-gated ion channels. This stimulus, typically brief in nature, leads to membrane potential depolarization, which increases ion flow across the membrane by increasing the open probability of these voltage-gated channels. In spiking neurons, it is activation of voltage-gated sodium channels (Na V channels) that leads to action potential generation. However, several other types of voltage-gated channels are expressed that also respond to electrical stimulation. In this study, we examine the response of voltage-gated potassium channels (K V channels) to brief electrical stimulation by whole cell patch-clamp electrophysiology and computational modeling. We show that nonspiking amacrine neurons of the retina exhibit a large variety of responses to stimulation, driven by different K V -channel subtypes. Computational modeling reveals substantial differences in the response of specific K V -channel subtypes that is dependent on channel kinetics. This suggests that the expression levels of different K V -channel subtypes in retinal neurons are a crucial predictor of the response that can be obtained. These data expand our knowledge of the mechanisms of neuronal activation and suggest that K V -channel expression is an important determinant of the sensitivity of neurons to electrical stimulation. NEW & NOTEWORTHY This paper describes the response of various voltage-gated potassium channels (K V channels) to brief electrical stimulation, such as is applied during prosthetic electrical stimulation. We show that the pattern of response greatly varies between K V channel subtypes depending on activation and inactivation kinetics of each channel. Our data suggest that problems encountered when artificially stimulating neurons such as cessation in firing at high frequencies, or

  7. High Tension Electric Current Injury and Silent Myocardial Infarction ...

    African Journals Online (AJOL)

    A 55-year-old male, non-diabetic, sustained severe electric current injury as evidenced by the grievous exit wound on the left dorsum of foot as well as entry wound in both palms. There was silent anterior wall myocardial infarction, discovered from incidental electrocardiograph. Keywords: Electric current injury, grievous exit ...

  8. Cataract and Retinal Detachment Following Electric Shock Injury in ...

    African Journals Online (AJOL)

    Aim: To report a case of cataract and retinal detachment following an electrical injury in an adult Nigerian male. C a se report: A 28-year-old man presented with a history of progressive and painless loss of vision in the right eye, three years after an electric shock injury. There was no history of mechanical trauma.

  9. A real-time voltage security assessment system (VSAS) at Alberta Electric System Operator

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L.; Howell, R.; Moshref, A. [Powertech Labs Inc., Surrey, BC (Canada); Mueller, M.; Viray, E.; Yang, C.; Qiu, J. [Alberta Electric System Operator, Calgary, AB (Canada)

    2008-07-01

    A fundamental requirement for a power system involves its secure and reliable operation. The diversity of operating conditions that exist in a system create a high degree of uncertainty with regard to the scenarios and contingencies that need to be examined to ensure system security. The Alberta Electric System Operator (AESO) is responsible for the safe, reliable and economic planning and operation of the Alberta interconnected electric system (AIES). Voltage stability is an issue due to transmission constraints in the AIES. This paper discussed AESO's implementation of an online voltage security assessment system (VSAS) using Powertech's voltage security assessment tool (VSAT) software at their system control center. Voltage security assessment at AESO and the performance requirements for VSAS were first described. The paper described the features of VSAS which included compliance with Western Electricity Coordinating Council voltage security criteria; real-time security monitoring and alarms; and suggestions of remedial actions when security violations were identified. The paper also detailed the development of the model, including contingencies; transfers; interfaces; monitored buses; special protection schemes; remedial action schemes; as well as other models applicable to voltage stability analysis. Computational scenarios that were included and analysed in VSAS for each real-time snapshot were also presented. Last, the paper described the system architecture and features and provided examples and operational experiences as well as future development plans. 11 refs., 6 figs.

  10. Management of Power Quality Issues in Low Voltage Networks using Electric Vehicles: Experimental Validation

    DEFF Research Database (Denmark)

    Martinenas, Sergejus; Knezovic, Katarina; Marinelli, Mattia

    2017-01-01

    the existing and future power quality problems. One of the main aspects of the power quality relates to voltage quality. The aim of this work is to experimentally analyse whether series-produced EVs, adhering to contemporary standard and without relying on any V2G capability, can mitigate line voltage drops...... in improving the power quality of a highly unbalanced grid......As Electric Vehicles (EVs) are becoming more wide spread, their high power consumption presents challenges for the residential low voltage networks, especially when connected to long feeders with unevenly distributed loads. However, if intelligently integrated, EVs can also partially solve...

  11. Architecture, Voltage, and Components for a Turboelectric Distributed Propulsion Electric Grid

    Science.gov (United States)

    Armstrong, Michael J.; Blackwelder, Mark; Bollman, Andrew; Ross, Christine; Campbell, Angela; Jones, Catherine; Norman, Patrick

    2015-01-01

    The development of a wholly superconducting turboelectric distributed propulsion system presents unique opportunities for the aerospace industry. However, this transition from normally conducting systems to superconducting systems significantly increases the equipment complexity necessary to manage the electrical power systems. Due to the low technology readiness level (TRL) nature of all components and systems, current Turboelectric Distributed Propulsion (TeDP) technology developments are driven by an ambiguous set of system-level electrical integration standards for an airborne microgrid system (Figure 1). While multiple decades' worth of advancements are still required for concept realization, current system-level studies are necessary to focus the technology development, target specific technological shortcomings, and enable accurate prediction of concept feasibility and viability. An understanding of the performance sensitivity to operating voltages and an early definition of advantageous voltage regulation standards for unconventional airborne microgrids will allow for more accurate targeting of technology development. Propulsive power-rated microgrid systems necessitate the introduction of new aircraft distribution system voltage standards. All protection, distribution, control, power conversion, generation, and cryocooling equipment are affected by voltage regulation standards. Information on the desired operating voltage and voltage regulation is required to determine nominal and maximum currents for sizing distribution and fault isolation equipment, developing machine topologies and machine controls, and the physical attributes of all component shielding and insulation. Voltage impacts many components and system performance.

  12. [The importance of electrocardiography in the clinical course of electric injuries].

    Science.gov (United States)

    Vural, Aslı; Sarak, Taner; Vural, Selahattin; Yastı, Ahmet Çınar

    2015-05-01

    The aim of the present study was to investigate the demographic and clinical characteristics of electrical injuries, type of electrical current and the importance of electrocardiography in clinical course. Fifty-three patients (50 males [94.3%], 3 females [5.7%]; mean age 34.5±9.6; range 19 to 61 years) with electrical injuries treated in the burn center between 2011 and 2012 were retrospectively analyzed. The patients were evaluated for demographic and clinical characteristics, electrocardiographic findings and clinical outcomes. The electrocardiography findings of the patients were as follows: twenty-seven normal, twelve sinus tachycardia, three atrial fibrillation, seven right bundle brunch block, and four ventricular extra-systole. There was no mortality among patients with electrocardiographic findings of normal, right bundle brunch block, and ventricular extra-systole. Four patients with sinus tachycardia and one patient with atrial fibrillation died. Electrocardiographic findings of the patients wounded by high-voltage electricity were: two normal, two sinus tachycardia, and one atrial fibrillation. Mortality was higher in patients with sinus tachycardia and atrial fibrillation in the electrocardiography at the time of admission. These ECG findings were more often in patients wounded by high-voltage electricity. Therefore, electrocardiographic findings and type of the electrical current may provide prognostic value in the clinical course of patients.

  13. A Field Study of Lightning Surges Propagating through Low-voltage Electric Appliances

    Science.gov (United States)

    Ishii, Tsunayoshi; Sakamoto, Yoshiki; Oguchi, Shuichi; Okabe, Shigemitsu

    In today's highly information-based society, lightning damage has a significant impact on an increasing number of electric appliances such as personal computers and facsimile machines. Lightning surge protection devices for electric appliances are on the market and concern for lightning protection has been increasing, but there are still many unknown aspects of lightning surges that propagate into residences. To provide effective lightning protection measures, clarification of surge propagation patterns is needed. The Tokyo Electric Power Company has observed the patterns of lightning surge propagation into houses using lightning surge waveform detectors installed at ordinary residences and obtained data on 30 lightning surge current waveforms between 2008 and 2009. This paper discusses various aspects of lightning surge currents propagating into low-voltage appliances, including home electric appliances, based on the lightning surge current waveform data obtained from lightning observations. The result revealed the patterns of lightning surge currents propagating into the ground and lines of low-voltage appliances.

  14. High-voltage electrical burns due to copper theft - Case series.

    Science.gov (United States)

    Braga, M J; Oliveira, I; Egipto, P; Silva, A

    2016-03-31

    Electrical burns are among the most devastating trauma inflicted on the human body. These burns have a higher morbidity, length of stay and a much higher risk of amputation than any other type of burn. Electrical burns affect mostly young, working males because they are more frequently the result of a work accident. However, possibly due to the worldwide economic crisis, we are experiencing a new phenomenon: the theft of high-voltage copper wiring.

  15. High-voltage electrical burns due to copper theft – Case series

    Science.gov (United States)

    Braga, M.J.; Oliveira, I.; Egipto, P.; Silva, A.

    2016-01-01

    Summary Electrical burns are among the most devastating trauma inflicted on the human body. These burns have a higher morbidity, length of stay and a much higher risk of amputation than any other type of burn. Electrical burns affect mostly young, working males because they are more frequently the result of a work accident. However, possibly due to the worldwide economic crisis, we are experiencing a new phenomenon: the theft of high-voltage copper wiring. PMID:27857650

  16. Orthopedic injury in electric bicycle-related collisions.

    Science.gov (United States)

    Li, Xiaoxuan; Yun, Zhe; Li, Xiaoxiang; Wang, Yucai; Yang, Tongtao; Zheng, Lianhe; Qian, Jixian

    2017-05-19

    Although electric bicycle-related injuries have become the most common reason for hospitalization due to a road crash in China, no study has comprehensively investigated electric bicycle collisions and their impact on orthopedic injuries; such a study may provide evidence to support a new road safety policy. A retrospective review of orthopedic injuries from electric bicycle collisions was performed in an urban trauma center. We collected variables including age, gender, location of fracture, presence of open or closed fractures, concomitant vascular, and neurologic injuries. A total of 2,044 cases were involved in electric bicycle collisions. The orthopedic injury victims were predominantly male and middle aged. The most common orthopedic injury was a femur fracture. Open fractures frequently involved the forearm and tibia/fibula. Male patients were more likely to suffer from multiple fractures and associated injuries than female patients. Fewer patients age 60 years old or older wore helmets at the time of the accident compared to those in other age groups. Orthopedic injuries from electric bicycle-related accidents cause patients substantial suffering that could lead to serious social consequences. Helmet use and protective clothing or similar safety gear, especially for electric bicycle users, should be required to provide greater protection.

  17. Power quality issues into a Danish low-voltage grid with electric vehicles

    DEFF Research Database (Denmark)

    Marra, Francesco; Jensen, Morten M.; Garcia-Valle, Rodrigo

    2011-01-01

    An increased interest on electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) is dealing with their introduction into low voltage (LV) distribution grids. Lately, analysis on power quality issues has received attention when considering EVs as additional load. The charging of EVs...... is expected without a centralized coordination in the first years, therefore a study on voltage variations and loading of LV grids is needed to estimate the immediate impact by EVs. In this work, the modeling and simulation of a Danish residential LV grid is conducted considering the two scenarios of dumb...... charging and overnight charging. The effect of different shares of EVs on voltage variations and transformer loading is assessed and analyzed. Results have shown that if single-phase, 16 A charging is employed, the actual LV grid would withstand the contingency of up to 30-40% of EVs charging overnight....

  18. Impact and Cost Evaluation of Electric Vehicle Integration on Medium Voltage Distribution Networks

    DEFF Research Database (Denmark)

    Wu, Qiuwei; Cheng, Lin; Pineau, Ulysse

    2013-01-01

    This paper presents the analysis of the impact of electric vehicle (EV) integration on medium voltage (MV) distribution networks and the cost evaluation of replacing the overloaded grid components. A number of EV charging scenarios have been studied. A 10 kV grid from the Bornholm Island...

  19. Assessing Losses of Power and Electrical Energy in Unbalanced Medium Voltage Distribution Networks

    Directory of Open Access Journals (Sweden)

    Toader C.

    2016-12-01

    Full Text Available The work is dedicated to calculating electricity losses related to power lines average voltage overhead or underground, which in terms of construction can be three-phase (three or four wire in unbalanced sinusoidal harmonic, determining energy efficiency indicators (such as positive and negative factors of unbalance thereof. It examines a case study and argues the results.

  20. The Preceding Voltage Pulse and Separation Welding Mechanism of Electrical Contacts

    DEFF Research Database (Denmark)

    Yang, Xiao Cheng; Huang, Jiang; Li, Zhen Biao

    2016-01-01

    In order to obtain a better understanding of the welding mechanism in contact separation, electrical endurance tests were conducted with AgSnO2 and AgNi contacts on a simulation test device. Waveforms of contact displacement, contact voltage, and current were recorded with LabVIEW during the tests...

  1. Electric Field Simulations and Analysis for High Voltage High Power Medium Frequency Transformer

    Directory of Open Access Journals (Sweden)

    Pei Huang

    2017-03-01

    Full Text Available The electronic power transformer (EPT raises concerns for its notable size and volume reduction compared with traditional line frequency transformers. Medium frequency transformers (MFTs are important components in high voltage and high power energy conversion systems such as EPTs. High voltage and high power make the reliable insulation design of MFT more difficult. In this paper, the influence of wire type and interleaved winding structure on the electric field distribution of MFT is discussed in detail. The electric field distributions for six kinds of typical non-interleaved windings with different wire types are researched using a 2-D finite element method (FEM. The electric field distributions for one non-interleaved winding and two interleaved windings are also studied using 2-D FEM. Furthermore, the maximum electric field intensities are obtained and compared. The results show that, in this case study, compared with foil conductor, smaller maximum electric field intensity can be achieved using litz wire in secondary winding. Besides, interleaving can increase the maximum electric field intensity when insulation distance is constant. The proposed method of studying the electric field distribution and analysis results are expected to make a contribution to the improvement of electric field distribution in transformers.

  2. Non-canonical spectral decomposition of random functions of the traction voltage and current in electric transportation systems

    Directory of Open Access Journals (Sweden)

    N.A. Kostin

    2015-03-01

    Full Text Available The paper proposes the non-canonical spectral decomposition of random functions of the traction voltages and currents. This decomposition is adapted for the electric transportation systems. The numerical representation is carried out for the random function of voltage on the pantograph of electric locomotives VL8 and DE1.

  3. Determination of exposure to electric fields in extra high voltage substations.

    Science.gov (United States)

    Lövstrand, K G

    1976-09-01

    Electrophysical effects related to extra high voltage are surveyed for the determination of the exposure of personnel to electric fields in substations. It is concluded that the electric field strengths and the electrical discharges to the personnel are the important electrophysical factors. Instruments for measuring the field strength at grounded surfaces and at nonzero potentials were constructed. Results are presented of measurements with these instruments in substations. A dummy was used for the measurement of the distribution of capacitive currents to a man. The dummy can also be used for measuring the effectiveness of special shielding clothes.

  4. Architecture, Voltage, and Components for a Turboelectric Distributed Propulsion Electric Grid (AVC-TeDP)

    Science.gov (United States)

    Gemin, Paul; Kupiszewski, Tom; Radun, Arthur; Pan, Yan; Lai, Rixin; Zhang, Di; Wang, Ruxi; Wu, Xinhui; Jiang, Yan; Galioto, Steve; hide

    2015-01-01

    The purpose of this effort was to advance the selection, characterization, and modeling of a propulsion electric grid for a Turboelectric Distributed Propulsion (TeDP) system for transport aircraft. The TeDP aircraft would constitute a miniature electric grid with 50 MW or more of total power, two or more generators, redundant transmission lines, and multiple electric motors driving propulsion fans. The study proposed power system architectures, investigated electromechanical and solid state circuit breakers, estimated the impact of the system voltage on system mass, and recommended DC bus voltage range. The study assumed an all cryogenic power system. Detailed assumptions within the study include hybrid circuit breakers, a two cryogen system, and supercritical cyrogens. A dynamic model was developed to investigate control and parameter selection.

  5. [Influences of high-voltage electrical burns on microcirculation perfusion on serosal surface of small intestine of rats and the interventional effects of pentoxifylline].

    Science.gov (United States)

    Zhang, Q F; Xu, S J; Liang, L M; Feng, J K; Xu, Y F; Tu, L L

    2017-03-20

    Objective: To investigate influences of high-voltage electrical burns on microcirculation perfusion on serosal surface of small intestine of rats and the interventional effects of pentoxifylline (PTX). Methods: Totally 180 SD rats were divided into sham injury group, simple electrical burn group, and treatment group according to the random number table, with 60 rats in each group. The electrical current was applied to the outside proximal part of left forelimb of rats and exited from the outside proximal part of right hind limb of rats. Rats in simple electrical burn group and treatment group were inflicted with high-voltage electrical burn wounds of 1cm×1cm at current entrances and exits, with the voltage regulator and experimental transformer. Rats in sham injury group were sham injured through connecting the same equipments without electricity. At 2 min post injury, rats in sham injury group and simple electrical burn group were intraperitoneally injected with 2 mL normal saline, and rats in treatment group were injected with 2 mL PTX injection (50 mg/mL). At 15 min before injury and 5 min, 1 h, 2 h, 4 h, and 8 h post injury, 10 rats in each group were selected to collect blood of heart respectively. Serum were separated from the blood to determine the level of soluble vascular cell adhesion molecule-1(sVCAM-1) with enzyme-linked immunosorbent assay method. The number of adhesional leukocyte in mesenteric venule of rats was determined with Bradford variable projection microscope system. The microcirculation perfusion on serosal surface of small intestine of rats was detected with laser Doppler perfusion imager. Data were processed with analysis of variance of factorial design and LSD test. Results: (1) At 5 min, 1 h, 2 h, 4 h, 8 h post injury, the serum content of sVCAM-1 in rats of simple electrical burn group were (8 502±1 158), (11 793±3 310), (9 960±2 146), (9 708±1 429), (7 292±1 386) ng/mL respectively, higher than that in sham injury group and

  6. Analytical Assessment of Voltage Support via Reactive Power from new Electric Vehicles Supply Equipment in Radial Distribution Grids with Voltage-Dependent Loads

    DEFF Research Database (Denmark)

    Zecchino, Antonio; Marinelli, Mattia

    2018-01-01

    Grid operators have to cope with secure electric vehicles integration in the power system, which may lead to violations of the allowed voltage band. This work intends to provide an analytical assessment and guidelines for distribution system operators when evaluating new electric vehicle supply...

  7. Fiber optic voltage sensor for 420 kV electric power systems

    Science.gov (United States)

    Bohnert, Klaus M.; Kostovic, Jadran; Pequignot, P.

    2000-11-01

    We present an optical fiber voltage sensor for 420 kV electric power lines. The sensor exploits the converse piezoelectric effect of quartz and measures the voltage by a line integration of the electric field. The alternating voltage is partitioned to a series of four cylinder-shaped quartz crystals, which are embedded in polyurethane resin within a 3.2-m long insulator tube of fiber reinforced epoxy. The alternating piezoelectric deformations of the crystals are sensed by a common elliptical-core dual-mode fiber, which is wound onto the circumferential crystal surfaces. The fiber is interrogated using low coherence interferometry. We determine the dielectric design of the sensor from a numerical analysis of the electric field distribution within and in the vicinity of the sensor. We experimentally verify the dielectric reliability under ac overvoltages up to 520 kV root mean square and lightning and switching impulse voltages up to 1425 and 1050 kV, respectively. Further, we investigate the sensor performance including accuracy, dynamic range, bandwidth, and temperature dependence.

  8. Background voltage distortion influence on power electric systems in the presence of the Steinmetz circuit

    Energy Technology Data Exchange (ETDEWEB)

    Sainz, Luis; Pedra, Joaquin [Department of Electrical Engineering, ETSEIB-UPC, Av. Diagonal 647, 08028 Barcelona (Spain); Caro, Manuel [IDOM Ingenieria y Arquitectura, C. Barcas 2, 46002 Valencia (Spain)

    2009-01-15

    In traction systems, it is usual to connect reactances in delta configuration with single-phase loads to reduce voltage unbalances and avoid electric system operation problems. This set is known as Steinmetz circuit. Parallel and series resonances can occur due to the capacitive reactance of the Steinmetz circuit and affect power quality. In this paper, the series resonance ''observed'' from the supply system is numerically located. The study of this resonance is important to avoid problems due to background voltage distortion. Experimental measurements are also presented to validate the obtained numerical results. (author)

  9. Impact Study of Electric Vehicle (EV) Integration on Medium Voltage (MV) Grids

    DEFF Research Database (Denmark)

    Wu, Qiuwei; Nielsen, Arne Hejde; Østergaard, Jacob

    2011-01-01

    The impact study of electric vehicle (EV) grid integration on medium voltage (MV) grids was carried out to quantify the power component loading and voltage profile change in MV grids due to the extra demands from the EV charging. Three charging scenarios, dumb charging, time charging and fleet...... operator based charging, were considered in the impact study to assess the impacts of different charging options. In the mean time, different charging power levels were included in the impact study as well. A MV grid from the Bornholm power system was used to implement the case studies....

  10. Low voltage electrical stimulation of lamb carcasses: effects on meat quality.

    Science.gov (United States)

    Polidori, P; Lee, S; Kauffman, R G; Marsh, B B

    1999-11-01

    The effects of an early post mortem low voltage electrical stimulation (28 V, 60 Hz) on biochemical changes and on final tenderness in muscles Longissimus thoracis et lumborum and Semimembranosus from lamb carcasses were studied. It was shown that electrical stimulation accelerated the glycolytic process resulting in a significant fall in pH during the first 6 h post mortem in both muscles examined and in a significant reduction in adenosine triphosphate (ATP) content in muscle Longissimus thoracis et lumborum. The effect of electrical stimulation on tenderness was recorded by measuring shear force values 2 and 7 days post mortem. Tenderness was significantly improved by electrical stimulation for the Longissimus thoracis et lumborum both at 2 and at 7 days post mortem, while for Semimembranosus electrical stimulation significantly increased tenderness just at 7 days post mortem.

  11. The design, construction, and operation of long-distance high-voltage electricity transmission technologies.

    Energy Technology Data Exchange (ETDEWEB)

    Molburg, J. C.; Kavicky, J. A.; Picel, K. C.

    2008-03-03

    This report focuses on transmission lines, which operate at voltages of 115 kV and higher. Currently, the highest voltage lines comprising the North American power grid are at 765 kV. The grid is the network of transmission lines that interconnect most large power plants on the North American continent. One transmission line at this high voltage was built near Chicago as part of the interconnection for three large nuclear power plants southwest of the city. Lines at this voltage also serve markets in New York and New England, also very high demand regions. The large power transfers along the West Coast are generally at 230 or 500 kV. Just as there are practical limits to centralization of power production, there are practical limits to increasing line voltage. As voltage increases, the height of the supporting towers, the size of the insulators, the distance between conductors on a tower, and even the width of the right-of-way (ROW) required increase. These design features safely isolate the electric power, which has an increasing tendency to arc to ground as the voltage (or electrical potential) increases. In addition, very high voltages (345 kV and above) are subject to corona losses. These losses are a result of ionization of the atmosphere, and can amount to several megawatts of wasted power. Furthermore, they are a local nuisance to radio transmission and can produce a noticeable hum. Centralized power production has advantages of economies of scale and special resource availability (for instance, hydro resources), but centralized power requires long-distance transfers of power both to reach customers and to provide interconnections for reliability. Long distances are most economically served at high voltages, which require large-scale equipment and impose a substantial footprint on the corridors through which power passes. The most visible components of the transmission system are the conductors that provide paths for the power and the towers that keep these

  12. Higher success rate with transcranial electrical stimulation of motor-evoked potentials using constant-voltage stimulation compared with constant-current stimulation in patients undergoing spinal surgery.

    Science.gov (United States)

    Shigematsu, Hideki; Kawaguchi, Masahiko; Hayashi, Hironobu; Takatani, Tsunenori; Iwata, Eiichiro; Tanaka, Masato; Okuda, Akinori; Morimoto, Yasuhiko; Masuda, Keisuke; Tanaka, Yuu; Tanaka, Yasuhito

    2017-10-01

    During spine surgery, the spinal cord is electrophysiologically monitored via transcranial electrical stimulation of motor-evoked potentials (TES-MEPs) to prevent injury. Transcranial electrical stimulation of motor-evoked potential involves the use of either constant-current or constant-voltage stimulation; however, there are few comparative data available regarding their ability to adequately elicit compound motor action potentials. We hypothesized that the success rates of TES-MEP recordings would be similar between constant-current and constant-voltage stimulations in patients undergoing spine surgery. The objective of this study was to compare the success rates of TES-MEP recordings between constant-current and constant-voltage stimulation. This is a prospective, within-subject study. Data from 100 patients undergoing spinal surgery at the cervical, thoracic, or lumbar level were analyzed. The success rates of the TES-MEP recordings from each muscle were examined. Transcranial electrical stimulation with constant-current and constant-voltage stimulations at the C3 and C4 electrode positions (international "10-20" system) was applied to each patient. Compound muscle action potentials were bilaterally recorded from the abductor pollicis brevis (APB), deltoid (Del), abductor hallucis (AH), tibialis anterior (TA), gastrocnemius (GC), and quadriceps (Quad) muscles. The success rates of the TES-MEP recordings from the right Del, right APB, bilateral Quad, right TA, right GC, and bilateral AH muscles were significantly higher using constant-voltage stimulation than those using constant-current stimulation. The overall success rates with constant-voltage and constant-current stimulations were 86.3% and 68.8%, respectively (risk ratio 1.25 [95% confidence interval: 1.20-1.31]). The success rates of TES-MEP recordings were higher using constant-voltage stimulation compared with constant-current stimulation in patients undergoing spinal surgery. Copyright © 2017

  13. Voltage inverter with push-pull topology to inject energy into electrical systems with modulation SPWM

    Directory of Open Access Journals (Sweden)

    Emerson Charles M. Silva

    2013-09-01

    Full Text Available This paper presents a proposal for a voltage inverter topology based on push-pull converters, switched at high frequency to inject energy into the grid from a source of DC power. A system using two reverse voltage static converters provides the power grid; energy in the form of alternating current, that can work in conjunction with the provision of utility power. Aiming at the possible use of renewable energy sources, that can be stored in the form of voltage continuous, such as wind, solar, hydroelectric and others. The functioning of topology is presented, such as the power and control circuits, as well as sizing components, theoretical and practical results achieved with the assembly of a prototype 100W of power and switching in 40khz, which after filtering provides the frequency of 60Hz, which is compatible with the Brazilian electrical system.

  14. The Effect of Current-Limiting Reactors on the Tripping of Short Circuits in High-Voltage Electrical Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Volkov, M. S.; Gusev, Yu. P., E-mail: GusevYP@mpei.ru; Monakov, Yu. V.; Cho, Gvan Chun [National Research University “Moscow Power Engineering Institute,” (Russian Federation)

    2016-01-15

    The insertion of current-limiting reactors into electrical equipment operating at a voltage of 110 and 220 kV produces a change in the parameters of the transient recovery voltages at the contacts of the circuit breakers for disconnecting short circuits, which could be the reason for the increase in the duration of the short circuit, damage to the electrical equipment and losses in the power system. The results of mathematical modeling of the transients, caused by tripping of the short circuit in a reactive electric power transmission line are presented, and data are given on the negative effect of a current-limiting resistor on the rate of increase and peak value of the transient recovery voltages. Methods of ensuring the standard requirements imposed on the parameters of the transient recovery voltages when using current-limiting reactors in the high-voltage electrical equipment of power plants and substations are proposed and analyzed.

  15. Current-voltage characteristics of light-emitting diodes under optical and electrical excitation

    Energy Technology Data Exchange (ETDEWEB)

    Wen Jing; Wen Yumei; Li Ping; Li Lian, E-mail: wenjing@cqu.edu.cn [Key Laboratory for Opto-Electronic Technologies and Systems of Ministry of Education, College of Opto-Electronic Engineering, Chongqing University, Chongqing 400044 (China)

    2011-08-15

    The factors influencing the current-voltage (I-V) characteristics of light-emitting diodes (LEDs) are investigated to reveal the connection of I-V characteristics under optical excitation and those under electrical excitation. By inspecting the I-V curves under optical and electrical excitation at identical injection current, it has been found that the I-V curves exhibit apparent differences in voltage values. Furthermore, the differences are found to originate from the junction temperatures in diverse excitation ways. Experimental results indicate that if the thermal effect of illuminating spot is depressed to an ignorable extent by using pulsed light, the junction temperature will hardly deflect from that under optical excitation, and then the I-V characteristics under two diverse excitation ways will be the same.

  16. Current-voltage characteristics of light-emitting diodes under optical and electrical excitation

    Science.gov (United States)

    Jing, Wen; Yumei, Wen; Ping, Li; Lian, Li

    2011-08-01

    The factors influencing the current—voltage (I—V) characteristics of light-emitting diodes (LEDs) are investigated to reveal the connection of I—V characteristics under optical excitation and those under electrical excitation. By inspecting the I—V curves under optical and electrical excitation at identical injection current, it has been found that the I—V curves exhibit apparent differences in voltage values. Furthermore, the differences are found to originate from the junction temperatures in diverse excitation ways. Experimental results indicate that if the thermal effect of illuminating spot is depressed to an ignorable extent by using pulsed light, the junction temperature will hardly deflect from that under optical excitation, and then the I—V characteristics under two diverse excitation ways will be the same.

  17. Photoinduced inverse spin-Hall effect: Conversion of light-polarization information into electric voltage

    Science.gov (United States)

    Ando, K.; Morikawa, M.; Trypiniotis, T.; Fujikawa, Y.; Barnes, C. H. W.; Saitoh, E.

    2010-02-01

    The photoinduced inverse spin-Hall effect was observed in a Pt/GaAs hybrid structure. In the GaAs layer, circularly polarized light generates spin-polarized carriers, inducing a pure spin current into the Pt layer through the interface. This pure spin current is, by the inverse spin-Hall effect in the Pt layer, converted into electric voltage. By changing the direction and ellipticity of the circularly polarized light, the electromotive force varies systematically, consistent with the prediction of the photoinduced inverse spin-Hall effect. The observed phenomenon allows the direct conversion of circular-polarization information into electric voltage; this phenomenon can be used as a spin photodetector.

  18. Study on the impact of electric vehicle charging load on nodal voltage deviation

    Directory of Open Access Journals (Sweden)

    Ma Gang

    2017-09-01

    Full Text Available The promotion and application of electric vehicles will contribute to the solution of several problems, such as energy shortage and environmental pollution, and the achievement of country economy and energy security. But a large-scale vehicle-to-grid system may cause adverse effects in the distribution network operation, the power network planning and such other parts. First, this paper collects the factors that influence the electric vehicle charging load and establishes the EV charging load model with a Monte-Carlo method. Then, we analyze the effect that the EV charging load made on the nodal voltage deviation under different permeability based on the IEEE30 node system. At last, this research gets the conclusion that the nodal voltage deviation is closely related to EV permeability, node type and node location. This research conclusion will provide practical guidance to the charging station planning.

  19. Electrical Stimulation for Pressure Injuries: A Health Technology Assessment

    Science.gov (United States)

    Lambrinos, Anna; Falk, Lindsey; Ali, Arshia; Holubowich, Corinne; Walter, Melissa

    2017-01-01

    Background Pressure injuries (bedsores) are common and reduce quality of life. They are also costly and difficult to treat. This health technology assessment evaluates the effectiveness, cost-effectiveness, budget impact, and lived experience of adding electrical stimulation to standard wound care for pressure injuries. Methods We conducted a systematic search for studies published to December 7, 2016, limited to randomized and non–randomized controlled trials examining the effectiveness of electrical stimulation plus standard wound care versus standard wound care alone for patients with pressure injuries. We assessed the quality of evidence through Grading of Recommendations Assessment, Development, and Evaluation (GRADE). In addition, we conducted an economic literature review and a budget impact analysis to assess the cost-effectiveness and affordability of electrical stimulation for treatment of pressure ulcers in Ontario. Given uncertainties in clinical evidence and resource use, we did not conduct a primary economic evaluation. Finally, we conducted qualitative interviews with patients and caregivers about their experiences with pressure injuries, currently available treatments, and (if applicable) electrical stimulation. Results Nine randomized controlled trials and two non–randomized controlled trials were found from the systematic search. There was no significant difference in complete pressure injury healing between adjunct electrical stimulation and standard wound care. There was a significant difference in wound surface area reduction favouring electrical stimulation compared with standard wound care. The only study on cost-effectiveness of electrical stimulation was partially applicable to the patient population of interest. Therefore, the cost-effectiveness of electrical stimulation cannot be determined. We estimate that the cost of publicly funding electrical stimulation for pressure injuries would be $0.77 to $3.85 million yearly for the next 5

  20. Control and Protection in Low Voltage Grid with Large Scale Renewable Electricity Generation

    DEFF Research Database (Denmark)

    Mustafa, Ghullam

    (s). Islanding is a situation where electrical system becomes electrically isolated from the rest of the power network and yet continues to be energized by the DG units connected to it. With the increased penetration of DG units, islanded operation of the distribution network is used to improve the reliability...... or voltage in MG decreases or increases respectively. It requires the significant amount of energy available in the power source with very fast response. A VF control cannot be used for wind and solar power generations because they are unpredictable and depend on the weather conditions (i.e. wind speed...

  1. Simulation study on transient electric shock characteristics of human body under high voltage ac transmission lines

    Science.gov (United States)

    Huang, Tao; Zou, Yanhui; Lv, Jianhong; Yang, Jinchun; Tao, Li; Zhou, Jianfei

    2017-09-01

    Human body under high-voltage AC transmission lines will produce a certain induced voltage due to the electrostatic induction. When the human body contacts with some grounded objects, the charges transfer from the body to the ground and produce contact current which may cause transient electric shock. Using CDEGS and ATP/EMTP, the paper proposes a method for quantitatively calculating the transient electric shock characteristics. It calculates the human body voltage, discharge current and discharge energy under certain 500kV compact-type transmission lines and predicts the corresponding human feelings. The results show that the average root value of discharge current is less than 10mA when the human body is under the 500kV compact-type transmission lines and the human body is overall safe if the transmission lines satisfy the relevant design specifications. It concludes that the electric field strength above the ground should be limited to 4kV/m through the residential area for the purpose of reducing the electromagnetic impact.

  2. Vibration, buckling and smart control of microtubules using piezoelectric nanoshells under electric voltage in thermal environment

    Energy Technology Data Exchange (ETDEWEB)

    Farajpour, A., E-mail: ariobarzan.oderj@gmail.com; Rastgoo, A.; Mohammadi, M.

    2017-03-15

    Piezoelectric nanomaterials such as zinc oxide (ZnO) are of low toxicity and have many biomedical applications including optical imaging, drug delivery, biosensing and harvesting biomechanical energy using hybrid nanogenerators. In this paper, the vibration, buckling and smart control of microtubules (MTs) embedded in an elastic medium in thermal environment using a piezoelectric nanoshell (PNS) are investigated. The MT and PNS are considered to be coupled by a filament network. The PNS is subjected to thermal loads and an external electric voltage which operates to control the mechanical behavior of the MT. Using the nonlocal continuum mechanics, the governing differential equations are derived. An exact solution is presented for simply supported boundary conditions. The differential quadrature method is also used to solve the governing equations for other boundary conditions. A detailed parametric study is conducted to investigate the effects of the elastic constants of surrounding medium and internal filament matrix, scale coefficient, electric voltage, the radius-to-thickness ratio of PNSs and temperature change on the smart control of MTs. It is found that the applied electric voltage can be used as an effective controlling parameter for the vibration and buckling of MTs.

  3. Vibration, buckling and smart control of microtubules using piezoelectric nanoshells under electric voltage in thermal environment

    Science.gov (United States)

    Farajpour, A.; Rastgoo, A.; Mohammadi, M.

    2017-03-01

    Piezoelectric nanomaterials such as zinc oxide (ZnO) are of low toxicity and have many biomedical applications including optical imaging, drug delivery, biosensing and harvesting biomechanical energy using hybrid nanogenerators. In this paper, the vibration, buckling and smart control of microtubules (MTs) embedded in an elastic medium in thermal environment using a piezoelectric nanoshell (PNS) are investigated. The MT and PNS are considered to be coupled by a filament network. The PNS is subjected to thermal loads and an external electric voltage which operates to control the mechanical behavior of the MT. Using the nonlocal continuum mechanics, the governing differential equations are derived. An exact solution is presented for simply supported boundary conditions. The differential quadrature method is also used to solve the governing equations for other boundary conditions. A detailed parametric study is conducted to investigate the effects of the elastic constants of surrounding medium and internal filament matrix, scale coefficient, electric voltage, the radius-to-thickness ratio of PNSs and temperature change on the smart control of MTs. It is found that the applied electric voltage can be used as an effective controlling parameter for the vibration and buckling of MTs.

  4. Carpal tunnel syndrome following an electrical injury in a child

    Science.gov (United States)

    Anand, Sambandam; Findlay, Alice Rima; Anand, Geetha

    2015-01-01

    Carpal tunnel syndrome (CTS) is very rare in children and has been reported very infrequently in the literature. We present an unusual case of CTS in a 14-year-old girl who developed this following an accidental electrical shock. As far as we are aware, this is the first case report of CTS in a child following electrical injury. This rare complication of electrical injury can easily be disregarded or misdiagnosed as neuropraxia, and this can delay appropriate treatment, as evidenced by this case. We propose that CTS should be considered when instigating initial medical care after an electrical injury, and that a referral to a hand surgeon should not be delayed, as these children need urgent surgical intervention to preserve hand function. PMID:25733087

  5. Carbon nanotubes for voltage reduction and throughput enhancement of electrical cell lysis on a lab-on-a-chip

    Science.gov (United States)

    Shahini, Mehdi; Yeow, John T. W.

    2011-08-01

    We report on the enhancement of electrical cell lysis using carbon nanotubes (CNTs). Electrical cell lysis systems are widely utilized in microchips as they are well suited to integration into lab-on-a-chip devices. However, cell lysis based on electrical mechanisms has high voltage requirements. Here, we demonstrate that by incorporating CNTs into microfluidic electrolysis systems, the required voltage for lysis is reduced by half and the lysis throughput at low voltages is improved by ten times, compared to non-CNT microchips. In our experiment, E. coli cells are lysed while passing through an electric field in a microchannel. Based on the lightning rod effect, the electric field strengthened at the tip of the CNTs enhances cell lysis at lower voltage and higher throughput. This approach enables easy integration of cell lysis with other on-chip high-throughput sample-preparation processes.

  6. Impact of control strategies for electric vehicles on low voltage grids; Auswirkungen von Steuerungsstrategien fuer Elektrofahrzeuge auf Niederspannungsnetze

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Lin; Rotering, Niklas; Moser, Albert [RWTH Aachen Univ. (Germany). Inst. fuer Elektrische Anlagen und Energiewirtschaft; Smolka, Thomas [Maschinenfabrik Reinhausen GmbH, Regensburg (Germany); Duisberg, Paul [STAWAG Netz GmbH, Aachen (Germany)

    2012-07-01

    In the project ''E-Aix: Elektromobiles Aachen'' sustainable mobility concepts are developed, researched and implemented based on electric vehicles and public utility infrastructures. To supply the vehicles with electric energy the establishment of a comprehensive recharging infrastructure is required. Taking into account the build-up of the infrastructure and the increasing number of electric vehicles, technical implications should be considered for electrical distribution grids. For this reason, a study based on representative grids of real low-voltage systems was conducted to determine the impacts of electric vehicles on the low voltage power grids. Special attention was paid to the effects of different control strategies. (orig.)

  7. Electrical conductivity and magnetic field dependent current-voltage characteristics of nanocrystalline nickel ferrite

    Science.gov (United States)

    Ghosh, P.; Bhowmik, R. N.; Das, M. R.; Mitra, P.

    2017-04-01

    We have studied the grain size dependent electrical conductivity, dielectric relaxation and magnetic field dependent current voltage (I - V) characteristics of nickel ferrite (NiFe2O4) . The material has been synthesized by sol-gel self-combustion technique, followed by ball milling at room temperature in air environment to control the grain size. The material has been characterized using X-ray diffraction (refined with MAUD software analysis) and Transmission electron microscopy. Impedance spectroscopy and I - V characteristics in the presence of variable magnetic fields have confirmed the increase of resistivity for the fine powdered samples (grain size 5.17±0.6 nm), resulted from ball milling of the chemical routed sample. Activation energy of the material for electrical charge hopping process has increased with the decrease of grain size by mechanical milling of chemical routed sample. The I - V curves showed many highly non-linear and irreversible electrical features, e.g., I - V loop and bi-stable electronic states (low resistance state-LRS and high resistance state-HRS) on cycling the electrical bias voltage direction during I-V curve measurement. The electrical dc resistance for the chemically routed (without milled) sample in HRS (∼3.4876×104 Ω) at 20 V in presence of magnetic field 10 kOe has enhanced to ∼3.4152×105 Ω for the 10 h milled sample. The samples exhibited an unusual negative differential resistance (NDR) effect that gradually decreased on decreasing the grain size of the material. The magneto-resistance of the samples at room temperature has been found substantially large (∼25-65%). The control of electrical charge transport properties under magnetic field, as observed in the present ferrimagnetic material, indicate the magneto-electric coupling in the materials and the results could be useful in spintronics applications.

  8. Electrical stimulation does not enhance nerve regeneration if delayed after sciatic nerve injury: the role of fibrosis

    Directory of Open Access Journals (Sweden)

    Na Han

    2015-01-01

    Full Text Available Electrical stimulation has been shown to accelerate and enhance nerve regeneration in sensory and motor neurons after injury, but there is little evidence that focuses on the varying degrees of fibrosis in the delayed repair of peripheral nerve tissue. In this study, a rat model of sciatic nerve transection injury was repaired with a biodegradable conduit at 1 day, 1 week, 1 month and 2 months after injury, when the rats were divided into two subgroups. In the experimental group, rats were treated with electrical stimuli of frequency of 20 Hz, pulse width 100 ms and direct current voltage of 3 V; while rats in the control group received no electrical stimulation after the conduit operation. Histological results showed that stained collagen fibers comprised less than 20% of the total operated area in the two groups after delayed repair at both 1 day and 1 week but after longer delays, the collagen fiber area increased with the time after injury. Immunohistochemical staining revealed that the expression level of transforming growth factor β (an indicator of tissue fibrosis decreased at both 1 day and 1 week after delayed repair but increased at both 1 and 2 months after delayed repair. These findings indicate that if the biodegradable conduit repair combined with electrical stimulation is delayed, it results in a poor outcome following sciatic nerve injury. One month after injury, tissue degeneration and distal fibrosis are apparent and are probably the main reason why electrical stimulation fails to promote nerve regeneration after delayed repair.

  9. Analysis and Comparison of Voltage Dependent Charging Strategies for Single-Phase Electric Vehicles in an Unbalanced Danish Distribution Grid

    DEFF Research Database (Denmark)

    Álvarez, Jorge Nájera; Knezovic, Katarina; Marinelli, Mattia

    2016-01-01

    This paper studies four voltage dependent solutions for modulating the charging of multiple Electric Vehicles (EVs) in a real Danish network. Uncontrolled EV charging, especially in grid with high EV penetration, can result in overloaded lines and transformers, low-voltages and other performance ...

  10. Statistics and probability analysis of the voltage on the pantograph of dc electric locomotive in the recuperation mode

    Directory of Open Access Journals (Sweden)

    V.M. Liashuk

    2012-12-01

    Full Text Available The statistical analysis and probability characteristics of voltage random variation on the pantograph of DC electric locomotive in the recuperation mode are presented in the article.

  11. Predictive Models of Current, Voltage, and Power Losses on Electric Transmission Lines

    Directory of Open Access Journals (Sweden)

    O. M. Bamigbola

    2014-01-01

    Full Text Available A modern and civilized society is so much dependent on the use of electrical energy because it has been the most powerful vehicle for facilitating economic, industrial, and social developments. Electrical energy produced at power stations is transmitted to load centres from where it is distributed to its consumers through the use of transmission lines run from one place to another. As a result of the physical properties of the transmission medium, some of the transmitted power is lost to the surroundings. The overall effect of power losses on the system is a reduction in the quantity of power available to the consumers. An accurate knowledge of transmission losses is hinged on the ability to correctly predict the available current and voltage along transmission lines. Therefore, mathematical physics expressions depicting the evolution of current and voltage on a typical transmission line were formulated, and derived therefrom were models to predict available current and voltage, respectively, at any point on the transmission line. The predictive models evolved as explicit expressions of the space variable and they are in close agreement with empirical data and reality.

  12. Entropy-Based Voltage Fault Diagnosis of Battery Systems for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Peng Liu

    2018-01-01

    Full Text Available The battery is a key component and the major fault source in electric vehicles (EVs. Ensuring power battery safety is of great significance to make the diagnosis more effective and predict the occurrence of faults, for the power battery is one of the core technologies of EVs. This paper proposes a voltage fault diagnosis detection mechanism using entropy theory which is demonstrated in an EV with a multiple-cell battery system during an actual operation situation. The preliminary analysis, after collecting and preprocessing the typical data periods from Operation Service and Management Center for Electric Vehicle (OSMC-EV in Beijing, shows that overvoltage fault for Li-ion batteries cell can be observed from the voltage curves. To further locate abnormal cells and predict faults, an entropy weight method is established to calculate the objective weight, which reduces the subjectivity and improves the reliability. The result clearly identifies the abnormity of cell voltage. The proposed diagnostic model can be used for EV real-time diagnosis without laboratory testing methods. It is more effective than traditional methods based on contrastive analysis.

  13. Spin control by application of electric current and voltage in FeCo-MgO junctions.

    Science.gov (United States)

    Suzuki, Yoshishige; Kubota, Hitoshi; Tulapurkar, Ashwin; Nozaki, Takayuki

    2011-09-28

    Efficient control and detection of spins are the most important tasks in spintronics. The current and voltage applied to a magnetic tunnel junction may exert a torque on the magnetic thin layer in the junction and cause its reversal or continuous precession. The discovery of the giant tunnelling magnetoresistance effect in ferromagnetic tunnelling junctions using an MgO barrier enabled us to obtain a large signal output from the magnetization reversal and precession. Also, the interplay of large spin configuration-electric conduction coupling provides highly nonlinear effects like the spin-torque diode effect. The negative resistance effect and amplification using it are predicted. A new discovery about a voltage-induced magnetic anisotropy change in Fe ultrathin films is also discussed.

  14. Cooling of electrically insulated high voltage electrodes down to 30 mK

    CERN Document Server

    Eisel, T; Burghart, G; Feigl, S; Haug, F; Koettig, T

    2011-01-01

    AEgIS [1] is an antimatter experiment, using high voltage electrodes at 100 mK. In this work two possible principles to cool these electrodes with a dilution refrigerator are described: the Rod and the Sandwich. The metallic Rod is electrically insulated by a ceramic and connects a single electrode directly with a heat exchanger placed in the mixing chamber. The Sandwich consists of an elec-trically insulating sapphire plate, at both sides covered with indium. The total thermal resistivities of the Rod and of different Sandwich samples are measured between (30 and 130) mK. The lowest resistivity of the Sandwich is achieved with indium vapour deposited on polished sapphire (26 cm2K4/W at 30 mK). The resistivity of the Rod is significantly lower (0.5 cm2K4/W at 30 mK).

  15. Green neighbourhoods in low voltage networks: measuring impact of electric vehicles and photovoltaics on load profiles

    CERN Document Server

    Hattam, Laura

    2016-01-01

    In the near future various types of low-carbon technologies (LCTs) are expected to be widely employed throughout the United Kingdom. However, the effect that these technologies will have at a household level on the existing low voltage (LV) network is still an area of extensive research. We propose an agent based model that estimates the growth of LCTs within local neighbourhoods, where social influence is imposed. Real-life data from a LV network is used that comprises of many socially diverse neighbourhoods. Both electric vehicle uptake and the combined scenario of electric vehicle and photovoltaic adoption are investigated with this data. A probabilistic approach is outlined, which determines lower and upper bounds for the model response at every neighbourhood. This technique is used to assess the implications of modifying model assumptions and introducing new model features. Moreover, we discuss how the calculation of these bounds can inform future network planning decisions.

  16. Assessing Short-Term Voltage Stability of Electric Power Systems by a Hierarchical Intelligent System.

    Science.gov (United States)

    Xu, Yan; Zhang, Rui; Zhao, Junhua; Dong, Zhao Yang; Wang, Dianhui; Yang, Hongming; Wong, Kit Po

    2016-08-01

    In the smart grid paradigm, growing integration of large-scale intermittent renewable energies has introduced significant uncertainties to the operations of an electric power system. This makes real-time dynamic security assessment (DSA) a necessity to enable enhanced situational-awareness against the risk of blackouts. Conventional DSA methods are mainly based on the time-domain simulation, which are insufficiently fast and knowledge-poor. In recent years, the intelligent system (IS) strategy has been identified as a promising approach to facilitate real-time DSA. While previous works mainly concentrate on the rotor angle stability, this paper focuses on another yet increasingly important dynamic insecurity phenomenon-the short-term voltage instability, which involves fast and complex load dynamics. The problem is modeled as a classification subproblem for transient voltage collapse and a prediction subproblem for unacceptable dynamic voltage deviation. A hierarchical IS is developed to address the two subproblems sequentially. The IS is based on ensemble learning of random-weights neural networks and is implemented in an offline training, a real-time application, and an online updating pattern. The simulation results on the New England 39-bus system verify its superiority in both learning speed and accuracy over some state-of-the-art learning algorithms.

  17. Electrical burn injuries of 246 patients treated at the University Clinical Center of Kosovo during the period 2005-2010.

    Science.gov (United States)

    Duci, S B; Arifi, H M; Ahmeti, H R; Selmani, M E; Buja, Z A; Gashi, M M; Zatriqi, V K; Mekaj, A Y

    2014-12-01

    In the developing world, the incidence of electrical injuries has increased in the past few years. Electrical injuries represent approximately 5 % of all burn admissions to burn units in the United States. The objective of this study is to understand the causes of electrical burns in our population, sex, age, duration of treatment, distribution of electrical burns by season, accompanying other traumatic injuries with electrical burns, entry lesions of high-voltage electrocution, location of injuries, the methods of treatment, duration of treatment, and mortality. This is a retrospective study that included 246 patients with electrical burns treated in the 2005-2010 period at the Department of Plastic and Reconstructive Surgery in Kosovo. The data were collected and analyzed from the archives and protocols of the University Clinical Center of Kosovo. Data processing was done with the statistical package InStat 3. From the statistical parameters the structural index, arithmetic median, and standard deviation were calculated. Data testing was done with the χ(2) test and the differences were considered significant if p < 0.05. The high mortality, 9.1 %, and 7 patients (10.6 %) transferred out of our country for treatment is a reflection of the lack of a burn center in our department.

  18. High voltage-power frequency electrical heating in-situ conversion technology of oil shale

    Science.gov (United States)

    Sun, Youhong; Yang, Yang; Lopatin, Vladimir; Guo, Wei; Liu, Baochang; Yu, Ping; Gao, Ke; Ma, Yinlong

    2014-05-01

    With the depletion of conventional energy sources,oil shale has got much attention as a new type of energy resource,which is rich and widespread in the world.The conventional utilization of oil shale is mainly focused on resorting to produce shale oil and fuel gas with low extraction efficiency about one in a million due to many shortcomings and limitations.And the in-situ conversion of oil shale,more environmentally friendly,is still in the experimental stage.High voltage-power frequency electrical heating in-situ conversion of oil shale is a new type of in-situ pyrolysis technology.The main equipment includes a high voltage-power frequency generator and interior reactor. The high voltage-power frequency generator can provide a voltage between 220-8000 V which can be adjusted in real time according to the actual situation.Firstly,high voltage is used to breakdown the oil shale to form a dendritic crack between two electrodes providing a conductive channel inside the oil shale rock.And then the power frequency(220V) is used to generate the electric current for heating the internal surface of conductive channel,so that the energy can be transmitted to the surrounding oil shale.When the temperature reaches 350 degree,the oil shale begins to pyrolysis.In addition,the temperature in the conductive channel can be extremely high with high voltage,which makes the internal surface of conductive channel graphitization and improves its heat conduction performance.This technology can successfully make the oil shale pyrolysis, based on a lot of lab experiments,and also produce the combustible shale oil and fuel gas.Compared to other in-situ conversion technology,this method has the following advantages: high speed of heating oil shale,the equipment underground is simple,and easy to operate;it can proceed without the limitation of shale thickness, and can be used especially in the thin oil shale reservoir;the heating channel is parallel to the oil shale layers,which has more

  19. Trends in electric bike-related injury in China, 2004-2010.

    Science.gov (United States)

    Zhang, Xujun; Cui, Mengjing; Gu, Yue; Stallones, Lorann; Xiang, Huiyun

    2015-03-01

    This study describes electric bike-related injuries from 2004 to 2010, and suggests injury prevention strategies to reduce electric bike-related injuries in China and other countries. Electric bike-related injuries data were obtained from the Bureau of Traffic Management at the Ministry of Public Security. Linear regression was used to identify statistically significant trends in electric bike-related injuries over the period. The results showed electric bike-related nonfatal injury rate had increased almost 4-fold and mortality rate increased 6-fold from 2004 to 2010. Linear regression showed a significant increase of 0.23 per 100 000 population per year (95% confidence interval = 0.18-0.29, P bike-related road traffic injuries. China will face new challenges arising from electric bike-related injuries. Programs need to be developed to prevent nonfatal injuries and fatalities caused by electric bike-related crashes in this country. © 2013 APJPH.

  20. Electrical properties of SnO{sub 2} ceramics for low voltage varistors

    Energy Technology Data Exchange (ETDEWEB)

    Glot, A.B., E-mail: alexglot@mixteco.utm.mx [Universidad Tecnologica de la Mixteca, Huajuapan de Leon 69000, Oaxaca (Mexico); Bulpett, R. [Brunel University, Uxbridge, UB8 3PH (United Kingdom); Ivon, A.I. [Dnepropetrovsk National University, Dnepropetrovsk 49010 (Ukraine); Gallegos-Acevedo, P.M. [Universidad Tecnologica de la Mixteca, Huajuapan de Leon 69000, Oaxaca (Mexico)

    2015-01-15

    It is shown that an addition of bismuth oxide Bi{sub 2}O{sub 3} (0.5 mol%) to the system SnO{sub 2}–CoO–Nb{sub 2}O{sub 5}–Cr{sub 2}O{sub 3} with small amounts of Nb{sub 2}O{sub 5} and Cr{sub 2}O{sub 3} (0.05 mol%) leads to a significant decrease in the electric field where a strong nonlinearity of the current–voltage characteristic takes place. This effect facilitates manufacture of ceramic materials for low voltage varistors with a relatively high nonlinearity coefficient of 15–20 and an electric field of 430−580Vcm{sup −1} (at a sintering temperature of 1300 °C) and, respectively, 11 and 287Vcm{sup −1} (at 1400 °C). The obtained experimental data indicate that ceramic materials in the system SnO{sub 2}–CoO–Nb{sub 2}O{sub 5}–Cr{sub 2}O{sub 3}–Bi{sub 2}O{sub 3} exhibit the typical structure of varistor ceramics with conductive grains of tin dioxide (SnO{sub 2}) and highly resistive grain boundaries. In particular, the capacitance at 10 Hz and high dc bias becomes negative as in other SnO{sub 2} and ZnO varistors.

  1. Effects of RTV coating on the electrical performance of polymer insulator under lightning impulse voltage condition.

    Directory of Open Access Journals (Sweden)

    Farah Adilah Jamaludin

    Full Text Available Located near the equator, Malaysia is a country with one of the highest lightning densities in the world. Lightning contributes to 70% of the power outages in Malaysia and affects power equipment, automated network systems, causes data losses and monetary losses in the nation. Therefore, consideration of insulator evaluation under lightning impulses can be crucial to evaluate and attempt to overcome this issue. This paper presents a new approach to increase the electrical performance of polymer insulators using a Room Temperature Vulcanisation (RTV coating. The evaluation involves three different settings of polymer insulator, namely uncoated, RTV type 1, and RTV type 2 upper surface coatings. All the insulators were tested under three different conditions as dry, clean wet and salty under different impulse polarities using the even-rising test method. The voltage breakdown for each test was recorded. From the experiment, it was found that the effectiveness of the RTV coating application became apparent when tested under salty or polluted conditions. It increased the voltage withstand capabilities of the polymer insulator up to 50% from the basic uncoated insulator. Under dry and clean conditions, the RTV coating provided just a slight increase of the breakdown voltage. The increase in voltage breakdown capability decreased the probability of surface discharge and dry band arcing that could cause degradation of the polymeric material housing. The RTV type 1 coating was found to be more effective when performing under a lightning impulse. The findings might help the utility companies improve the performance of their insulators in order to increase power system reliability.

  2. Effects of RTV coating on the electrical performance of polymer insulator under lightning impulse voltage condition.

    Science.gov (United States)

    Jamaludin, Farah Adilah; Ab-Kadir, Mohd Zainal Abidin; Izadi, Mahdi; Azis, Norhafiz; Jasni, Jasronita; Abd-Rahman, Muhammad Syahmi

    2017-01-01

    Located near the equator, Malaysia is a country with one of the highest lightning densities in the world. Lightning contributes to 70% of the power outages in Malaysia and affects power equipment, automated network systems, causes data losses and monetary losses in the nation. Therefore, consideration of insulator evaluation under lightning impulses can be crucial to evaluate and attempt to overcome this issue. This paper presents a new approach to increase the electrical performance of polymer insulators using a Room Temperature Vulcanisation (RTV) coating. The evaluation involves three different settings of polymer insulator, namely uncoated, RTV type 1, and RTV type 2 upper surface coatings. All the insulators were tested under three different conditions as dry, clean wet and salty under different impulse polarities using the even-rising test method. The voltage breakdown for each test was recorded. From the experiment, it was found that the effectiveness of the RTV coating application became apparent when tested under salty or polluted conditions. It increased the voltage withstand capabilities of the polymer insulator up to 50% from the basic uncoated insulator. Under dry and clean conditions, the RTV coating provided just a slight increase of the breakdown voltage. The increase in voltage breakdown capability decreased the probability of surface discharge and dry band arcing that could cause degradation of the polymeric material housing. The RTV type 1 coating was found to be more effective when performing under a lightning impulse. The findings might help the utility companies improve the performance of their insulators in order to increase power system reliability.

  3. Effects of RTV coating on the electrical performance of polymer insulator under lightning impulse voltage condition

    Science.gov (United States)

    Jamaludin, Farah Adilah; Ab-Kadir, Mohd Zainal Abidin; Izadi, Mahdi; Azis, Norhafiz; Jasni, Jasronita; Abd-Rahman, Muhammad Syahmi

    2017-01-01

    Located near the equator, Malaysia is a country with one of the highest lightning densities in the world. Lightning contributes to 70% of the power outages in Malaysia and affects power equipment, automated network systems, causes data losses and monetary losses in the nation. Therefore, consideration of insulator evaluation under lightning impulses can be crucial to evaluate and attempt to overcome this issue. This paper presents a new approach to increase the electrical performance of polymer insulators using a Room Temperature Vulcanisation (RTV) coating. The evaluation involves three different settings of polymer insulator, namely uncoated, RTV type 1, and RTV type 2 upper surface coatings. All the insulators were tested under three different conditions as dry, clean wet and salty under different impulse polarities using the even-rising test method. The voltage breakdown for each test was recorded. From the experiment, it was found that the effectiveness of the RTV coating application became apparent when tested under salty or polluted conditions. It increased the voltage withstand capabilities of the polymer insulator up to 50% from the basic uncoated insulator. Under dry and clean conditions, the RTV coating provided just a slight increase of the breakdown voltage. The increase in voltage breakdown capability decreased the probability of surface discharge and dry band arcing that could cause degradation of the polymeric material housing. The RTV type 1 coating was found to be more effective when performing under a lightning impulse. The findings might help the utility companies improve the performance of their insulators in order to increase power system reliability. PMID:29136025

  4. Perspectives of Safe Work Practices: Improving Personal Electrical Safety of Low-Voltage Systems from Electrical Hazards

    Directory of Open Access Journals (Sweden)

    Y. Mobarak,

    2016-12-01

    Full Text Available A person’s understanding of a safety hazard has a dramatic effect on his or her behavior. An in-depth understanding of a hazard usually results in a healthy respect for what can happen. People who know the most about a specific hazard tend to rely more heavily on procedures and plans to guide their actions. Personal protective equipment selection and use are influenced by increased understanding of a hazard. Training and training programs are influenced by the depth of knowledge held by all members of the line organization. Recent work has focused attention on the thermal effects of arc flashes. However, when electrical energy is converted into thermal energy in an arcing fault, still another energy conversion is taking place. Applications are on record that suggest that a considerable amount of force is created during an arcing fault. Concrete block walls can be destroyed by the increased pressure that is created during an arcing fault. This study is present about preventing injuries to people. We will study about injuries and then develop some understanding about electrical hazards. Also, we will present about safe work practices, responsible, and then about what makes us act as we do.

  5. PIEZOELECTRIC WAVEGUIDE SENSOR FOR MEASURING PULSE PRESSURE IN CLOSED LIQUID VOLUMES AT HIGH VOLTAGE ELECTRIC DISCHARGE

    Directory of Open Access Journals (Sweden)

    V. G. Zhekul

    2017-10-01

    Full Text Available Purpose. Investigations of the characteristics of pressure waves presuppose the registration of the total profile of the pressure wave at a given point in space. For these purposes, various types of «pressure to the electrical signal» transmitters (sensors are used. Most of the common sensors are unsuitable for measuring the pulse pressure in a closed water volume at high hydrostatic pressures, in particular to study the effect of a powerful high-voltage pulse discharge on increasing the inflow of minerals and drinking water in wells. The purpose of the work was to develop antijamming piezoelectric waveguide sensor for measuring pulse pressure at a close distance from a high-voltage discharge channel in a closed volume of a liquid. Methodology. We have applied the calibration method as used as a secondary standard, the theory of electrical circuits. Results. We have selected the design and the circuit solution of the waveguide pressure sensor. We have developed a waveguide pulse-pressure sensor DTX-1 with a measuring loop. This sensor makes it possible to study the spectral characteristics of pressure waves of high-voltage pulse discharge in closed volumes of liquid at a hydrostatic pressure of up to 20 MPa and a temperature of up to 80 °C. The sensor can be used to study pressure waves with a maximum amplitude value of up to 150 MPa and duration of up to 80 µs. According to the results of the calibration, the sensitivity of the developed sensor DTX-1 with a measuring loop is 0.0346 V/MPa. Originality. We have further developed the theory of designing the waveguide piezoelectric pulse pressure sensors for measuring the pulse pressure at a close distance from a high-voltage discharge channel in a closed fluid volume by controlling the attenuation of the amplitude of the pressure signal. Practical value. We have developed, created, calibrated, used in scientific research waveguide pressure pulse sensors DTX-1. We propose sensors DTX-1 for sale

  6. ON SELECTION OF CIRCUIT-BREAKERS SWITCHING ELECTRICAL INSTALLATIONS OF HIGH AND EXTRA-HIGH VOLTAGE

    Directory of Open Access Journals (Sweden)

    T. M. Lazimov

    2005-01-01

    Full Text Available The paper proposes some additional conditions for high-voltage circuit-breaker selection keeping in mind coordination of the switched over-voltages and voltages induced in secondary circuits with their permissible values.

  7. Phase-wise enhanced voltage support from electric vehicles in a Danish low-voltage distribution grid

    DEFF Research Database (Denmark)

    Knezovic, Katarina; Marinelli, Mattia

    2016-01-01

    while the energy losses are not notably increased. Further on, since the control is voltage dependent, provided reactive power is unequal among the phases leading to greater support on heavily loaded phases and decreased unbalances caused by residential consumption. Hence, implementation of such a phase-wise...

  8. Investigation of voltages and electric fields in silicon semi 3D radiation detectors using Silvaco/ATLAS simulation tool and a scanning electron microscope

    CERN Document Server

    Palviainen, T; Tuuva, T; Eranen, S; Härkönen, J; Luukka, P; Tuovinen, E

    2006-01-01

    The structure of silicon semi three-dimensional radiation detector is simulated on purpose to find out its electrical characteristics such as the depletion voltage and electric field. Two-dimensional simulation results are compared to voltage and electric field measurements done by a scanning electron microscope.

  9. Electric Arc Furnace Modeling with Artificial Neural Networks and Arc Length with Variable Voltage Gradient

    Directory of Open Access Journals (Sweden)

    Raul Garcia-Segura

    2017-09-01

    Full Text Available Electric arc furnaces (EAFs contribute to almost one third of the global steel production. Arc furnaces use a large amount of electrical energy to process scrap or reduced iron and are relevant to study because small improvements in their efficiency account for significant energy savings. Optimal controllers need to be designed and proposed to enhance both process performance and energy consumption. Due to the random and chaotic nature of the electric arcs, neural networks and other soft computing techniques have been used for modeling EAFs. This study proposes a methodology for modeling EAFs that considers the time varying arc length as a relevant input parameter to the arc furnace model. Based on actual voltages and current measurements taken from an arc furnace, it was possible to estimate an arc length suitable for modeling the arc furnace using neural networks. The obtained results show that the model reproduces not only the stable arc conditions but also the unstable arc conditions, which are difficult to identify in a real heat process. The presented model can be applied for the development and testing of control systems to improve furnace energy efficiency and productivity.

  10. Evaluation of the contact switch materials in high voltage power supply for generate of underwater shockwave by electrical discharge

    Directory of Open Access Journals (Sweden)

    K Higa

    2016-10-01

    Full Text Available We have developed the high voltage power-supply unit by Cockcroft-Walton circuit for ingenerate high pressure due to underwater shockwave by electrical discharge. This high voltage power supply has the problem of the metal contact switch operation that contact switch stop by melting and bonding due to electrical spark. We have studied the evaluation of materials of contact switch for the reducing electrical energy loss and the problem of contact switch operation. In this research, measurement of discharge voltage and high pressure due to underwater shockwave was carried out using the contact switch made of different materials as brass plate, brass-carbon plate-brass and carbon block. The contact switch made of carbon is effective to reduce energy loss and problem of contactor switch operation.

  11. INFLUENCE OF RARE-EARTH DOPING ON THE ELECTRICAL PROPERTIES OF HIGH VOLTAGE GRADIENT ZnO VARISTORS

    Directory of Open Access Journals (Sweden)

    LEI KE

    2013-03-01

    Full Text Available The influence of rare-earth doping on the electrical properties of ZnO varistors was investigated. In a lower doping region, the electrical properties were greatly improved with the increase of rare-earth contents. The highest voltage gradient value of 1968.0 V/mm was obtained with a rare-earth concentration of 0.06 mol. %. The microstructure of samples with different amounts of rare-earth oxides was examined and the notable decrease of grain size was identified as the origin for the increased voltage gradient. The doped rare-earth oxides dissolved at the grain boundaries and the excessive doping reduced the voltage across the single grain/grain boundary from 2.72 V to 0.91 V. The poor electrical properties in a higher doping region resulted from the degeneration of grain boundaries and the decrease of block density.

  12. Shut-Off Valves of Electric Drive with Thyristor Voltage Regulators and Software Implementation of the Indirect Determination of Moment

    Directory of Open Access Journals (Sweden)

    Vlasov Anton I.

    2017-01-01

    Full Text Available In this paper we consider the shut-off valve of electric drive with thyristor voltage regulator and microprocessor control which ensures a constant indirect control of torque value on the electric drive as well as its limitation in the case of the creation of an emergency on the main oil pipeline. It was found that the use of the integrated microprocessor control systems with software implementation calculating of given torque in the system of induction motor - thyristor voltage regulator, allows you to get the best performance of electric drive shut-off valve with the restrictions on the maximum current, torque whith deviations of voltage parameters and improve the safety of the process of oil pumping.

  13. Effect of voltage shape of electrical power supply on radiation and density of a cold atmospheric argon plasma jet

    Directory of Open Access Journals (Sweden)

    F Sohbatzadeh

    2017-02-01

    Full Text Available In this work, we investigated generating argon cold plasma jet at atmospheric pressure based on dielectric barrier discharge configuration using three electrical power supplies of sinusoidal, pulsed and saw tooth high voltage shapes at 8 KHZ. At first; we describe the electronic circuit features for generating high voltage (HV wave forms including saw tooth, sinusoidal and pulsed forms. Then, we consider the effect of voltage shape on the electrical breakdown. Relative concentrations of chemical reactive species such as Oxygen, atomic Nitrogen and OH were measured using optical emission spectroscopy. Using a simple numerical model, we showed a HV with less rise time increases electron density, therefore a cold plasma jet can be produced with a minimal consumption electrical power

  14. Environmental justice: a contrary finding for the case of high-voltage electric power transmission lines.

    Science.gov (United States)

    Wartenberg, Daniel; Greenberg, Michael R; Harris, Gerald

    2010-05-01

    Environmental justice is the consideration of whether minority and/or lower-income residents in a geographic area are likely to have disproportionately higher exposures to environmental toxins than those living elsewhere. Such situations have been identified for a variety of factors, such as air pollution, hazardous waste, water quality, noise, residential crowding, and housing quality. This study investigates the application of this concept to high-voltage electric power transmission lines (HVTL), which some perceive as a health risk because of the magnetic fields they generate, and also as esthetically unpleasing. We mapped all 345 kV and higher voltage HVTL in New York State and extracted and summarized proximate US Census sociodemographic and housing characteristic data into four categories on the basis of distances from HVTL. Contrary to our expectation, people living within 2000 ft from HVTL were more likely to be exposed to magnetic fields, white, of higher income, more educated and home owners, than those living farther away, particularly in urban areas. Possible explanations for these patterns include the desire for the open space created by the rights-of-way, the preference for new homes/subdivisions that are often located near HVTL, and moving closer to HVTL before EMFs were considered a risk. This study suggests that environmental justice may not apply to all environmental risk factors and that one must be cautious in generalizing. In addition, it shows the utility of geographical information system methodology for summarizing information from extremely large populations, often a challenge in epidemiology.

  15. High-Voltage, High-Power Gaseous Electronics Switch For Electric Grid Power Conversion

    Science.gov (United States)

    Sommerer, Timothy J.

    2014-05-01

    We are developing a high-voltage, high-power gas switch for use in low-cost power conversion terminals on the electric power grid. Direct-current (dc) power transmission has many advantages over alternating current (ac) transmission, but at present the high cost of ac-dc power interconversion limits the use of dc. The gas switch we are developing conducts current through a magnetized cold cathode plasma in hydrogen or helium to reach practical current densities > 1 A/cm2. Thermal and sputter damage of the cathode by the incident ion flux is a major technical risk, and is being addressed through use of a ``self-healing'' liquid metal cathode (eg, gallium). Plasma conditions and cathode sputtering loss are estimated by analyzing plasma spectral emission. A particle-in-cell plasma model is used to understand various aspects of switch operation, including the conduction phase (where plasma densities can exceed 1013 cm-3), the switch-open phase (where the high-voltage must be held against gas breakdown on the left side of Paschen's curve), and the switching transitions (especially the opening process, which is initiated by forming an ion-matrix sheath adjacent to a control grid). The information, data, or work presented herein was funded in part by the Advanced Research Projects Agency-Energy (ARPA-E), U.S. Department of Energy, under Award Number DE-AR0000298.

  16. A Complex Permittivity Based Sensor for the Electrical Characterization of High-Voltage Transformer Oils

    Directory of Open Access Journals (Sweden)

    Panayota Vassiliou

    2005-05-01

    Full Text Available This work investigates the use of a specially designed cylindrical metal cell, inorder to obtain complex permittivity and tanδ data of highly insulating High Voltage (HVtransformer oil samples. The data are obtained at a wide range of frequencies and operationtemperatures to demonstrate the polarization phenomena and the thermally stimulatedeffects. Such complex permittivity measurements may be utilized as a criterion for theservice life prediction of oil field electrical equipment (OFEE. Therefore, by one set ofmeasurements on a small oil volume, data may be provided on the impending termination,or continuation of the transformer oil service life. The oil incorporating cell, attached to theappropriate measuring units, could be described as a complex permittivity sensor. In thiswork, the acquired dielectric data from a great number of operating distribution networkpower transformers were correlated to corresponding physicochemical ones to demonstratethe future potential employment of the proposed measuring technique.

  17. A Complex Permittivity Based Sensor for the Electrical Characterization of High-Voltage Transformer Oils

    Science.gov (United States)

    Dervos, Constantine T.; Paraskevas, Christos D.; Skafidas, Panayotis D.; Vassiliou, Panayota

    2005-01-01

    This work investigates the use of a specially designed cylindrical metal cell, in order to obtain complex permittivity and tanδ data of highly insulating High Voltage (HV) transformer oil samples. The data are obtained at a wide range of frequencies and operation temperatures to demonstrate the polarization phenomena and the thermally stimulated effects. Such complex permittivity measurements may be utilized as a criterion for the service life prediction of oil field electrical equipment (OFEE). Therefore, by one set of measurements on a small oil volume, data may be provided on the impending termination, or continuation of the transformer oil service life. The oil incorporating cell, attached to the appropriate measuring units, could be described as a complex permittivity sensor. In this work, the acquired dielectric data from a great number of operating distribution network power transformers were correlated to corresponding physicochemical ones to demonstrate the future potential employment of the proposed measuring technique.

  18. Extension of the Accurate Voltage-Sag Fault Location Method in Electrical Power Distribution Systems

    Directory of Open Access Journals (Sweden)

    Youssef Menchafou

    2016-03-01

    Full Text Available Accurate Fault location in an Electric Power Distribution System (EPDS is important in maintaining system reliability. Several methods have been proposed in the past. However, the performances of these methods either show to be inefficient or are a function of the fault type (Fault Classification, because they require the use of an appropriate algorithm for each fault type. In contrast to traditional approaches, an accurate impedance-based Fault Location (FL method is presented in this paper. It is based on the voltage-sag calculation between two measurement points chosen carefully from the available strategic measurement points of the line, network topology and current measurements at substation. The effectiveness and the accuracy of the proposed technique are demonstrated for different fault types using a radial power flow system. The test results are achieved from the numerical simulation using the data of a distribution line recognized in the literature.

  19. FPGA-based voltage and current dual drive system for high frame rate electrical impedance tomography.

    Science.gov (United States)

    Khan, Shadab; Manwaring, Preston; Borsic, Andrea; Halter, Ryan

    2015-04-01

    Electrical impedance tomography (EIT) is used to image the electrical property distribution of a tissue under test. An EIT system comprises complex hardware and software modules, which are typically designed for a specific application. Upgrading these modules is a time-consuming process, and requires rigorous testing to ensure proper functioning of new modules with the existing ones. To this end, we developed a modular and reconfigurable data acquisition (DAQ) system using National Instruments' (NI) hardware and software modules, which offer inherent compatibility over generations of hardware and software revisions. The system can be configured to use up to 32-channels. This EIT system can be used to interchangeably apply current or voltage signal, and measure the tissue response in a semi-parallel fashion. A novel signal averaging algorithm, and 512-point fast Fourier transform (FFT) computation block was implemented on the FPGA. FFT output bins were classified as signal or noise. Signal bins constitute a tissue's response to a pure or mixed tone signal. Signal bins' data can be used for traditional applications, as well as synchronous frequency-difference imaging. Noise bins were used to compute noise power on the FPGA. Noise power represents a metric of signal quality, and can be used to ensure proper tissue-electrode contact. Allocation of these computationally expensive tasks to the FPGA reduced the required bandwidth between PC, and the FPGA for high frame rate EIT. In 16-channel configuration, with a signal-averaging factor of 8, the DAQ frame rate at 100 kHz exceeded 110 frames s (-1), and signal-to-noise ratio exceeded 90 dB across the spectrum. Reciprocity error was found to be for frequencies up to 1 MHz. Static imaging experiments were performed on a high-conductivity inclusion placed in a saline filled tank; the inclusion was clearly localized in the reconstructions obtained for both absolute current and voltage mode data.

  20. Electrical bioimpedance enabling prompt intervention in traumatic brain injury

    Science.gov (United States)

    Seoane, Fernando; Atefi, S. Reza

    2017-05-01

    Electrical Bioimpedance (EBI) is a well spread technology used in clinical practice across the world. Advancements in Textile material technology with conductive textile fabrics and textile-electronics integration have allowed exploring potential applications for Wearable Measurement Sensors and Systems exploiting. The sensing principle of electrical bioimpedance is based on the intrinsic passive dielectric properties of biological tissue. Using a pair of electrodes, tissue is electrically stimulated and the electrical response can be sensed with another pair of surface electrodes. EBI spectroscopy application for cerebral monitoring of neurological conditions such as stroke and perinatal asphyxia in newborns have been justified using animal studies and computational simulations. Such studies have shown proof of principle that neurological pathologies indeed modify the dielectric composition of the brain that is detectable via EBI. Similar to stroke, Traumatic Brain Injury (TBI) also affects the dielectric properties of brain tissue that can be detected via EBI measurements. Considering the portable and noninvasive characteristics of EBI it is potentially useful for prehospital triage of TBI patients where. In the battlefield blast induced Traumatic Brain Injuries are very common. Brain damage must be assessed promptly to have a chance to prevent severe damage or eventually death. The relatively low-complexity of the sensing hardware required for EBI sensing and the already proven compatibility with textile electrodes suggest the EBI technology is indeed a candidate for developing a handheld device equipped with a sensorized textile cap to produce an examination in minutes for enabling medically-guided prompt intervention.

  1. Continuous extraction of phenolic compounds from pomegranate peel using high voltage electrical discharge.

    Science.gov (United States)

    Xi, Jun; He, Lang; Yan, Liang-Gong

    2017-09-01

    Pomegranate peel, a waste generated from fruit processing industry, is a potential source of phenolic compounds that are known for their anti-oxidative properties. In this study, a continuous high voltage electrical discharge (HVED) extraction system was for the first time designed and optimized for phenolic compounds from pomegranate peel. The optimal conditions for HVED were: flow rate of materials 12mL/min, electrodes gap distance 3.1mm (corresponding to 29kV/cm of electric field intensity) and liquid to solid ratio 35mL/g. Under these conditions, the experimental yield of phenolic compounds was 196.7±6.4mg/g, which closely agreed with the predicted value (199.83mg/g). Compared with the warm water maceration, HVED method possessed higher efficiency for the extraction of phenolic compounds. The results demonstrated that HVED technique could be a very effective method for continuous extraction of natural compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Effect of Transportation and Low Voltage Electrical Stimulation on Meat Quality Characteristics of Omani Sheep

    Directory of Open Access Journals (Sweden)

    Isam T. Kadim

    2010-01-01

    Full Text Available The aim of this study was to determine the effects of road transportation during the hot season (36 oC and low voltage electrical stimulation on meat quality characteristics of Omani sheep. Twenty intact male sheep (1-year old were divided into two equal groups: 3 hrs transported or non-transported. The transported group was transferred to the slaughterhouse the day of slaughter in an open truck covering a distance of approximately 300 km. The non-transported group was kept in a lairage of a commercial slaughterhouse with ad libitum feed and water for 3 days prior to slaughter. Blood samples were collected from the animals before loading and prior to slaughter in order to assess their physiological response to stress in terms of hormonal levels. Fifty percent of the carcasses from each group were randomly assigned to low voltage (90 V at 20 min postmortem. Muscle ultimate pH, expressed juice, cooking loss percentage, WB-shear force value, sarcomere length, myofibrillar fragmentation index and colour L*, a*, b* were measured on samples from Longissimus dorsi muscles collected 24 hrs postmortem at 2-4 oC. The transported sheep had significantly (P<0.05 higher cortisol adrenaline, nor-adrenaline, and dopamine levels than the non-transported group. Muscles from electrically-stimulated carcasses had significantly (P<0.05 lower pH values, longer sarcomere length, lower shear force value, higher expressed juice, myofibrillar fragmentation index and L* values than those from non-stimulated ones. Transportation significantly influenced meat quality characteristics of the Longissimus dorsi muscle. Muscle ultimate pH and shear force values were significantly higher, while CIE L*, a*, b*, expressed juice and cooking loss were lower in transported than non-transported sheep. This study indicated that pre-slaughter transportation at high ambient temperatures can cause noticeable changes in muscle physiology in sheep. Nevertheless, meat quality of transported

  3. Optimal Coordinated Management of a Plug-In Electric Vehicle Charging Station under a Flexible Penalty Contract for Voltage Security

    Directory of Open Access Journals (Sweden)

    Jip Kim

    2016-07-01

    Full Text Available The increasing penetration of plug-in electric vehicles (PEVs may cause a low-voltage problem in the distribution network. In particular, the introduction of charging stations where multiple PEVs are simultaneously charged at the same bus can aggravate the low-voltage problem. Unlike a distribution network operator (DNO who has the overall responsibility for stable and reliable network operation, a charging station operator (CSO may schedule PEV charging without consideration for the resulting severe voltage drop. Therefore, there is a need for the DNO to impose a coordination measure to induce the CSO to adjust its charging schedule to help mitigate the voltage problem. Although the current time-of-use (TOU tariff is an indirect coordination measure that can motivate the CSO to shift its charging demand to off-peak time by imposing a high rate at the peak time, it is limited by its rigidity in that the network voltage condition cannot be flexibly reflected in the tariff. Therefore, a flexible penalty contract (FPC for voltage security to be used as a direct coordination measure is proposed. In addition, the optimal coordinated management is formulated. Using the Pacific Gas and Electric Company (PG&E 69-bus test distribution network, the effectiveness of the coordination was verified by comparison with the current TOU tariff.

  4. The impacts of voltage sags in industrial electric systems; Os impactos dos afundamentos de tensao em sistemas eletricos industriais

    Energy Technology Data Exchange (ETDEWEB)

    Maia, Reinaldo Moreira [Moinhos Vera Cruz, Santa Luzia, MG (Brazil); Silva, Selenio Rocha [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2010-10-15

    The sensitiveness increasing of industrial equipment related to the perturbation of electric grid, resulting in losses to the productive chain, turns the energy quality in the subject more discussed by the electrical community. In this study case on the problems caused by voltage sags to equipment of an industrial plant from the food sector, it is presented the identification process and the adopted solutions. (author)

  5. Electrical Power Supply to Offshore Oil Installations by High Voltage Direct Current Transmission

    Energy Technology Data Exchange (ETDEWEB)

    Myhre, Joergen Chr.

    2001-07-01

    This study was initiated to investigate if it could be feasible to supply offshore oil installations in the North Sea with electrical power from land. A prestudy of alternative converter topologies indicated that the most promising solution would be to investigate a conventional system with reduced synchronous compensator rating. The study starts with a summary of the state of power supply to offshore installations today, and a short review of classical HVDC transmission. It goes on to analyse how a passive network without sources influences the inverter. The transmission, with its current controlled rectifier and large inductance, is simulated as a current source. Under these circumstances the analysis shows that the network frequency has to adapt in order to keep the active and reactive power balance until the controllers are able to react. The concept of firing angle for a thyristor is limited in a system with variable frequency, the actual control parameter is the firing delay time. Sensitivity analysis showed some astonishing consequences. The frequency rises both by an increase in the active and in the reactive load. The voltage falls by an increase in the active load, but rises by an increase in the inductive load. Two different control principles for the system of inverter, synchronous compensator and load are defined. The first takes the reference for the firing delay time from the fundamental voltage at the point of common coupling. The second takes the reference for the firing delay time from the simulated EMF of the synchronous compensator. Of these, the second is the more stable and should be chosen as the basis for a possible control system. Two simulation tools are applied. The first is a quasi-phasor model running on Matlab with Simulink. The other is a time domain model in KREAN. The time domain model is primarily used for the verification of the quasi-phasor model, and shows that quasi-phasors is still a valuable tool for making a quick analysis

  6. Electrical impedance myography changes after incomplete cervical spinal cord injury: An examination of hand muscles.

    Science.gov (United States)

    Li, Le; Shin, Henry; Stampas, Argyrios; Li, Xiaoyan; Zhou, Ping

    2017-11-01

    This study was to apply the newly developed electrical impedance myography (EIM) technique to examine hand muscles in patients with an incomplete cervical spinal cord injury (SCI). EIM was performed on the thenar, hypothenar, and first dorsal interosseous (FDI) muscles of SCI (n=16) and age-matched healthy control (n=18) subjects. By sending low intensity and high frequency current through the skin and measuring the consequent voltage, EIM estimates the major impedance parameters, which include resistance (R), reactance (X) and phase angle (θ). The SCI group had lower reactance and phase angle (pmuscles, and lower resistance in the thenar muscle (pmuscles could be due tochanges of membrane integrity and fat infiltration, whereas the change in the anisotropy may reflect the rearrangement of muscle fiber geometry. The EIM provides a quick and convenient tool for examination of muscle alterations after SCI. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  7. Integration of 100% heat pumps and electric vehicles in the low voltage distribution network: A Danish case story

    DEFF Research Database (Denmark)

    Shao, Nan; You, Shi; Segerberg, Helena

    2013-01-01

    The existing electricity infrastructure may to a great extent limit a high penetration of micro-sized Distributed Energy Rescores (DERs), due to physical bottlenecks, e.g. load capacities of cables and transformers and voltage limitations. In this study, integration impacts of heat pumps (HPs...

  8. Measurement and Modeling of Personal Exposure to the Electric and Magnetic Fields in the Vicinity of High Voltage Power Lines

    Directory of Open Access Journals (Sweden)

    Wafa Tourab

    2016-06-01

    Conclusion: We project to set own national standards for exposure to electromagnetic fields, in order to achieve a regional database that will be at the disposal of partners concerned to ensure safety of people and mainly workers inside high voltage electrical substations.

  9. Over Expression of Voltage Dependent Anion Channel 2 (VDAC2 in Muscles of Electrically Stunned Chickens

    Directory of Open Access Journals (Sweden)

    Norshahida Abu Samah, Azura Amid, and Faridah Yusof

    2011-12-01

    Full Text Available Water bath stunning is a common practice in commercial slaughterhouses. Such treatment is economic and in line with animal welfare practice. However, the conditions applied for the stunning process may vary from a slaughterhouse to another slaughterhouse. Such a loose regulation on the stunning procedure has opened up doors for food adulteration such as over dose stunning. In this study, a simple and reliable approach using proteomics have been developed to study the effect of different currents and voltages in stunning on the protein expression of the chickens. Protein profiles of the chickens were constructed in order to detect any differences in protein expression and modifications. The different voltage studied were 10 V, 40 V and 70 V while the values for current studied were 0.25 A, 0.5 A, and 0.75 A. After the proteomics analyses using 2D Platinum ImageMaster 6.0 and Matrix-assisted laser desorption ionization- time of flight (MALDI TOF spectrometry identification, Voltage dependent anion channel 2 (VDAC2 was identified to be over expressed in the muscle sample of over stunned chicken. The over expression of VDAC2 was confirmed at the transcriptional level of RNA expression. Real Time PCR showed that all over stunned samples contained higher mRNA expression level for VDAC2 genes. The mRNA level of VDAC2 was up-regulated by 59.87 fold change when normalized with housekeeping gene. In conclusion, VDAC2 could serve as potential biomarkers for identification of electrically stimulated chickens. The existence of these biomarkers will help to monitor the slaughtering and stunning process in the future. It will revolutionize the food authentication field and give a new breathe to the meat industry.ABSTRAK: Kaedah "waterbath stunning" merupakan amalan biasa di pusat-pusat penyembelihan. Kaedah ini adalah ekonomik dan selari dengan amalan kebajikan haiwan. Walaubagaimanapun, syarat-syarat yang digunakan untuk proses kejutan tersebut mungkin

  10. Does static electric field from ultra-high voltage direct-current transmission lines affect male reproductive capacity? Evidence from a laboratory study on male mice.

    Science.gov (United States)

    Wu, Sixia; Di, Guoqing; Li, Zhengguang

    2017-08-01

    With the development of ultra-high-voltage direct-current (UHVDC) transmission technology and increase in transmission voltage, the issue of environmental static electric field (SEF) pollution is standing out and its possible health effects have caused much public attention. In this study, the effects of chronic exposure to SEF on reproductive capacity of male mice were investigated. Twenty Institute of Cancer Research (ICR) mice were exposed to SEF (56.3 ± 1.4 kV/m, 49 days) generated by a high-voltage device. Several biological end points related to spermatogenesis and testicular function were evaluated, including reproductive organ coefficients, sperm motility and morphology, serum testosterone level, and testicular histology. No significant differences were found between the SEF-exposed and sham-exposed groups at the end of the exposure period. However, further observation through transmission electron microscopy revealed cristae losses in mitochondria of spermatogenic cells after SEF exposure. Nevertheless, the mitochondria injury did not affect sperm motility, which might be explained from the perspective of energy supply. That is, most of the energy required for sperm movement is generated by glycolysis which occurs in the cytoplasm rather than oxidative phosphorylation which occurs in mitochondria. In conclusion, this study indicates that exposure to SEF (56.3 ± 1.4 kV/m, 49 days) has limited effects on male reproductive capacity.

  11. Impact of pulsed-electric field and high-voltage electrical discharges on red wine microbial stabilization and quality characteristics.

    Science.gov (United States)

    Delsart, C; Grimi, N; Boussetta, N; Miot Sertier, C; Ghidossi, R; Vorobiev, E; Mietton Peuchot, M

    2016-01-01

    In this study, pulsed-electric fields (PEF) and high-voltage electrical discharges (HVED) are proposed as new techniques for the microbial stabilization of red wines before bottling. The efficiency of the treatment was then evaluated. PEF and HVED-treatments have been applied to wine for the inactivation of Oenococcus oeni CRBO 9304, O. oeni CRBO 0608, Pediococcus parvulus CRBO 2.6 and Brettanomyces bruxellensis CB28. Different treatment times (1, 2, 4, 6, 8 and 10 ms) were used at 20 kV cm(-1) for the PEF treatments and at 40 kV for the HVED treatments, which correspond to applied energies from 80 to 800 kJ l(-1) . The effects of the treatments on the microbial inactivation rate and on various characteristics of red wines (phenolic composition, chromatic characteristics and physico-chemical parameters) were measured. The application of PEF or HVED treatments on red wine allowed the inactivation of alteration yeasts (B. bruxellensis CB28) and bacteria (O. oeni CRBO 9304, O. oeni CRBO 0608 and P. parvulus CRBO 2.6). The electric discharges at 40 kV were less effective than the PEF even after 10 ms of treatments. Indeed, 4 ms of PEF treatment at 20 kV cm(-1) were sufficient to inactivate all micro-organisms present in the wines. Also, the use of PEF had no negative impact on the composition of wines compared to the HVED treatments. Contrary to PEF, the phenolics compounds were degraded after the HVED treatment and the physico-chemical composition of wine were modified with HVED. PEF technology seems to be an interesting alternative to stabilize microbiologically wines before bottling and without modifying their composition. This process offers many advantages for winemakers: no chemical inputs, low energy consumption (320 kJ l(-1) ), fast (treatment time of 4 ms) and athermal (ΔT ≈ 10°C). © 2015 The Society for Applied Microbiology.

  12. Design of High Voltage Electrical Breakdown Strength measuring system at 1.8K with a G-M cryocooler

    Science.gov (United States)

    Li, Jian; Huang, Rongjin; Li, Xu; Xu, Dong; Liu, Huiming; Li, Laifeng

    2017-09-01

    Impregnating resins as electrical insulation materials for use in ITER magnets and feeder system are required to be radiation stable, good mechanical performance and high voltage electrical breakdown strength. In present ITER project, the breakdown strength need over 30 kV/mm, for future DEMO reactor, it will be greater than this value. In order to develop good property insulation materials to satisfy the requirements of future fusion reactor, high voltage breakdown strength measurement system at low temperature is necessary. In this paper, we will introduce our work on the design of this system. This measuring system has two parts: one is an electrical supply system which provides the high voltage from a high voltage power between two electrodes; the other is a cooling system which consists of a G-M cryocooler, a superfluid chamber and a heat switch. The two stage G-M cryocooler pre-cool down the system to 4K, the superfluid helium pot is used for a container to depress the helium to superfluid helium which cool down the sample to 1.8K and a mechanical heat switch connect or disconnect the cryocooler and the pot. In order to provide the sufficient time for the test, the cooling system is designed to keep the sample at 1.8K for 300 seconds.

  13. Effect of cathodal high-voltage electrical stimulation on pain in women with TMD.

    Science.gov (United States)

    Gomes, Natalia C M C; Berni-Schwarzenbeck, Kelly C S; Packer, Amanda C; Rdrigues-Bigaton, Delaine

    2012-01-01

    Pain is the main symptom of patients with temporomandibular disorder (TMD). To evaluate the effect of cathodal high-voltage electrical stimulation (HVES) on pain intensity in women with TMD. Twenty women with TMD (24.25 ± 8.90 years old) participated in the study. They were divided into experimental group (EG, n=10), which received 10 applications of HVES, and placebo group (PG, n=10), which received sham treatment with disconnected HVES equipment. For the sample selection, we used the Research Diagnostic Criteria for Temporomandibular Disorder (RDC/TMD). Pain level was evaluated using a visual analog scale (VAS) applied prior to and after the tenth application of HVES. Data were analyzed using the Wilcoxon signed-rank test and the Mann-Whitney test. Ten applications of HVES reduced pain intensity in the EG (p=0.01). In the PG, there was no significant difference (p=0.20). After the application of HVES, no difference was found (p=0.65) between the groups. The cathodal HVES was effective in reducing pain in women with TMD. Trial Registration RBR-4bk94x.

  14. Cooling of electrically insulated high voltage electrodes down to 30 mK: Dynamic measurements

    CERN Document Server

    Eisel, T; Burghart, G; Feigl, S; Haug, F; Koettig, T

    2011-01-01

    AEgIS [1] is an antimatter experiment, using high voltage electrodes at 100 mK. Two possible principles to cool these electrodes with a dilution refrigerator are investigated: the Rod and the Sandwich. Both designs are described in detail in [2]. The Sandwich design is discussed in the present work. It consists of an electrically insulating sapphire plate covered with indium on both sides. Dynamic measurements are performed in order to estimate the influence of time depending heat loads on different Sandwich designs. From these data the Sandwich’s thermal diffusivity is derived and compared to previous measurements using a static heat load. The lowest resistivity of the Sandwich is achieved with an indium vapor deposition onto polished sapphire (26 cm2K4/W at 30 mK). The same sandwich shows the best, i.e. highest thermal diffusivity (0.23 mm2/s at 70 mK). However, the results of the static and the dynamic measurements show some interesting and contrary tendencies.

  15. Simple voltage-controlled current source for wideband electrical bioimpedance spectroscopy: circuit dependences and limitations

    Science.gov (United States)

    Seoane, F.; Macías, R.; Bragós, R.; Lindecrantz, K.

    2011-11-01

    In this work, the single Op-Amp with load-in-the-loop topology as a current source is revisited. This circuit topology was already used as a voltage-controlled current source (VCCS) in the 1960s but was left unused when the requirements for higher frequency arose among the applications of electrical bioimpedance (EBI). The aim of the authors is not only limited to show that with the currently available electronic devices it is perfectly viable to use this simple VCCS topology as a working current source for wideband spectroscopy applications of EBI, but also to identify the limitations and the role of each of the circuit components in the most important parameter of a current for wideband applications: the output impedance. The study includes the eventual presence of a stray capacitance and also an original enhancement, driving with current the VCCS. Based on the theoretical analysis and experimental measurements, an accurate model of the output impedance is provided, explaining the role of the main constitutive elements of the circuit in the source's output impedance. Using the topologies presented in this work and the proposed model, any electronic designer can easily implement a simple and efficient current source for wideband EBI spectroscopy applications, e.g. in this study, values above 150 kΩ at 1 MHz have been obtained, which to the knowledge of the authors are the largest values experimentally measured and reported for a current source in EBI at this frequency.

  16. Effects of Thermal and Solvent Aging on Breakdown Voltage of TPE, PBT/PET Alloy, and PBT Insulated Low Voltage Electric Wire

    Directory of Open Access Journals (Sweden)

    Eun-Soo Park

    2013-01-01

    Full Text Available Tests were performed to evaluate the effects of thermal and solvent aging on the mechanical and dielectric breakdown properties of four types of polyester resins, namely, the insulation layer of poly(butylene terephthalat (PBT- based thermoplastic elastomer (TPE, TPE1, poly(butylene 2,6-naphthalate-based TPE (TPE2, PBT/poly(ethylene terephthalate alloy (Alloy, and PBT extruded onto a copper conductor of low voltage electric wire. The tensile specimens used in this series were prepared from the same extruded resins. The prepared electric wires and tensile specimens were thermally aged in air and in toluene, xylene, TCB, and NMP. When Alloy and PBT were thermally aged in toluene, xylene and TCB at 120°C for 6 h, the tensile properties were significantly decreased compared to TPE1 and TPE2 at the same condition. The reduction of elongation at break of Alloy was more discernible than that of PBT. This result indicated that Alloy is more affected by thermal and solvent ageing. Among them, TPE2 showed the highest breakdown voltage (BDV, and it has also the highest BDV after thermal and solvent aging.

  17. Cerebrovascular accident (CVA) in association with a Taser-induced electrical injury.

    Science.gov (United States)

    Bell, Nicholas; Moon, Matthew; Dross, Peter

    2014-04-01

    Various adverse outcomes related to the use of electrical weapons such as the stun gun or the Taser have been described in the literature over the years. Examples include cardiac arrhythmias, blunt and penetrating injuries, seizure activity, and altered mental status. Imaging findings related to electrical injuries have become more frequent with advancing imaging technologies, such as CT or MRI. However, imaging findings and pathophysiology of electrical injuries that result in significant neurological events remain largely unexplored. We report the case of a patient who developed an ischemic stroke following Taser discharge, raising the possibility of association between the electrical injury and the ischemic stroke.

  18. Theoretical aspects and methods of parameters identification of the electric traction system devices. method of cyclic current-voltage characteristics

    Directory of Open Access Journals (Sweden)

    T.M.Mishchenko

    2013-02-01

    Full Text Available Purpose. To define the characteristics of numerical calculations of mathematical model with one or more cyclic current voltage characteristics (CVC. This is an urgent problem, since any electric traction system device and electrified track in general, like non-linear passive or active two-terminal network in the present operating mode is described by current-voltage characteristic (CVC, which is based on the given input voltage and input current. Me-thodology. The electromagnetic process calculation in the power circuits of traction electric energy supply is the probabilistic task with solving nonlinear stochastic differential equations requiring for the development of special methods. Given the calculation difficulty, it is reasonable to perform them either by real CVC graph bypass or initially by applying its equivalent replacement with, for example, an ellipse. Findings. Numerical calculations of the mathematical model with one or more cyclic CVC can be performed by “real” CVC bypass or by "idealization" i. e. approximate replacement of real cyclic CVC. Originality. This paper presents the dynamic CVC of the DS3 and 2ES5K electric locomotives at different currents of electric locomotives. Practical value. Cyclic CVC normally and definitely can be applied in the system of electromagnetic state equations while transient state calculating in the traction system. Therefore while calculating the experimentally obtained CVC for the most “difficult and complex” (or/and the “easiest” mode is applied.

  19. Decomposition of Composite Electric Field in a Three-Phase D-Dot Voltage Transducer Measuring System.

    Science.gov (United States)

    Hu, Xueqi; Wang, Jingang; Wei, Gang; Deng, Xudong

    2016-10-12

    In line with the wider application of non-contact voltage transducers in the engineering field, transducers are required to have better performance for different measuring environments. In the present study, the D-dot voltage transducer is further improved based on previous research in order to meet the requirements for long-distance measurement of electric transmission lines. When measuring three-phase electric transmission lines, problems such as synchronous data collection and composite electric field need to be resolved. A decomposition method is proposed with respect to the superimposed electric field generated between neighboring phases. The charge simulation method is utilized to deduce the decomposition equation of the composite electric field and the validity of the proposed method is verified by simulation calculation software. With the deduced equation as the algorithm foundation, this paper improves hardware circuits, establishes a measuring system and constructs an experimental platform for examination. Under experimental conditions, a 10 kV electric transmission line was tested for steady-state errors, and the measuring results of the transducer and the high-voltage detection head were compared. Ansoft Maxwell Stimulation Software was adopted to obtain the electric field intensity in different positions under transmission lines; its values and the measuring values of the transducer were also compared. Experimental results show that the three-phase transducer is characterized by a relatively good synchronization for data measurement, measuring results with high precision, and an error ratio within a prescribed limit. Therefore, the proposed three-phase transducer can be broadly applied and popularized in the engineering field.

  20. Decomposition of Composite Electric Field in a Three-Phase D-Dot Voltage Transducer Measuring System

    Directory of Open Access Journals (Sweden)

    Xueqi Hu

    2016-10-01

    Full Text Available In line with the wider application of non-contact voltage transducers in the engineering field, transducers are required to have better performance for different measuring environments. In the present study, the D-dot voltage transducer is further improved based on previous research in order to meet the requirements for long-distance measurement of electric transmission lines. When measuring three-phase electric transmission lines, problems such as synchronous data collection and composite electric field need to be resolved. A decomposition method is proposed with respect to the superimposed electric field generated between neighboring phases. The charge simulation method is utilized to deduce the decomposition equation of the composite electric field and the validity of the proposed method is verified by simulation calculation software. With the deduced equation as the algorithm foundation, this paper improves hardware circuits, establishes a measuring system and constructs an experimental platform for examination. Under experimental conditions, a 10 kV electric transmission line was tested for steady-state errors, and the measuring results of the transducer and the high-voltage detection head were compared. Ansoft Maxwell Stimulation Software was adopted to obtain the electric field intensity in different positions under transmission lines; its values and the measuring values of the transducer were also compared. Experimental results show that the three-phase transducer is characterized by a relatively good synchronization for data measurement, measuring results with high precision, and an error ratio within a prescribed limit. Therefore, the proposed three-phase transducer can be broadly applied and popularized in the engineering field.

  1. CONSIDERATIONS FOR FAILURE PREVENTION IN AEROSPACE ELECTRICAL POWER SYSTEMS UTILIZING HIGHER VOLTAGES

    Science.gov (United States)

    2017-07-01

    lead to a reduction in partial discharge inception voltages in the order of 50% [7]. However, localized heat sources can lead to systems having to...Halleck leads to the upper chart in Figure 2 that shows the RMS voltage rating that could be applied to a cable before partial discharge takes place...and between the turns and the core. Additionally, all types of machine insulation may have to cope with voltages higher than would be expected based

  2. BEHAVIOUR OF BACKFILL MATERIALS FOR ELECTRICAL GROUNDING SYSTEMS UNDER HIGH VOLTAGE CONDITIONS

    Directory of Open Access Journals (Sweden)

    S. C. LIM

    2015-06-01

    Full Text Available Backfill materials like Bentonite and cement are effective in lowering grounding resistance of electrodes for a considerable period. During lightning, switching impulses and earth fault occurrences in medium and high voltage networks, the grounding system needs to handle extremely high currents either for a short duration or prolonged period respectively. This paper investigates the behaviour of bentonite, cement and sand under impulse and alternating high voltage (50Hz conditions. Fulguritic-formation was observed in all materials under alternating high voltage. The findings reveal that performance of grounding systems under high voltage conditions may significantly change from the outcomes anticipated at design stage.

  3. Frequency and voltage dependent electrical responses of poly(triarylamine thin film-based organic Schottky diode

    Directory of Open Access Journals (Sweden)

    Mohamad Khairul Anuar

    2017-01-01

    Full Text Available A metal-organic-metal (MOM type Schottky diode based on poly (triarylamine (PTAA thin films has been fabricated by using the spin coating method. Investigation of the frequency dependent conductance-voltage (G-V-f and capacitance-voltage (C-V-f characteristics of the ITO/PTAA/Al MOM type diode were carried out in the frequency range from 12 Hz to 100 kHz using an LCR meter at room temperature. The frequency and bias voltage dependent electrical response were determined by admittance-based measured method in terms of an equivalent circuit model of the parallel combination of resistance and capacitance (RC circuit. Investigation revealed that the conductance is frequency and a bias voltage dependent in which conductance continuous increase as the increasing frequency, respectively. Meanwhile, the capacitance is dependent on frequency up to a certain value of frequency (100 Hz but decreases at high frequency (1 – 10 kHz. The interface state density in the Schottky diode was determined from G-V and C-V characteristics. The interface state density has values almost constant of 2.8 x 1012 eV−1cm−2 with slightly decrease by increasing frequencies. Consequently, both series resistance and interface trap density were found to decrease with increasing frequency. The frequency dependence of the electrical responses is attributed the distribution density of interface states that could follow the alternating current (AC signal.

  4. Frequency and voltage dependent electrical responses of poly(triarylamine) thin film-based organic Schottky diode

    Science.gov (United States)

    Anuar Mohamad, Khairul; Tak Hoh, Hang; Alias, Afishah; Ghosh, Bablu Kumar; Fukuda, Hisashi

    2017-11-01

    A metal-organic-metal (MOM) type Schottky diode based on poly (triarylamine) (PTAA) thin films has been fabricated by using the spin coating method. Investigation of the frequency dependent conductance-voltage (G-V-f) and capacitance-voltage (C-V-f) characteristics of the ITO/PTAA/Al MOM type diode were carried out in the frequency range from 12 Hz to 100 kHz using an LCR meter at room temperature. The frequency and bias voltage dependent electrical response were determined by admittance-based measured method in terms of an equivalent circuit model of the parallel combination of resistance and capacitance (RC circuit). Investigation revealed that the conductance is frequency and a bias voltage dependent in which conductance continuous increase as the increasing frequency, respectively. Meanwhile, the capacitance is dependent on frequency up to a certain value of frequency (100 Hz) but decreases at high frequency (1 - 10 kHz). The interface state density in the Schottky diode was determined from G-V and C-V characteristics. The interface state density has values almost constant of 2.8 x 1012 eV-1cm-2 with slightly decrease by increasing frequencies. Consequently, both series resistance and interface trap density were found to decrease with increasing frequency. The frequency dependence of the electrical responses is attributed the distribution density of interface states that could follow the alternating current (AC) signal.

  5. The effect of gate voltage on the electrical transport properties in the contacts of C60 to carbon nanotube leads

    Directory of Open Access Journals (Sweden)

    AA Shokri

    2012-06-01

    Full Text Available  In this paper, we examined the effect of gate voltage, bias voltage, contact geometries and the different bond lengths on the electrical transport properties in a nanostructure consisting of C60 molecule attached to two semi-infinite leads made of single wall carbon nanotubes in the coherent regime. Our calculation was based on the Green’s function method within nearest-neighbour tight-binding approximation. After the calculation was of transmission, the electrical current was obtained by the Landauer-Buttiker formula. Next, the effect of the mentioned factors was investigated in the nanostructure. The application of the present results may be useful in designing devices based on molecular electronics in nanoscale.

  6. The effect of high voltage, high frequency pulsed electric field on slain ovine cortical bone.

    Science.gov (United States)

    Asgarifar, Hajarossadat; Oloyede, Adekunle; Zare, Firuz

    2014-04-01

    High power, high frequency pulsed electric fields known as pulsed power (PP) has been applied recently in biology and medicine. However, little attention has been paid to investigate the application of pulse power in musculoskeletal system and its possible effect on functional behavior and biomechanical properties of bone tissue. This paper presents the first research investigating whether or not PP can be applied safely on bone tissue as a stimuli and what will be the possible effect of these signals on the characteristics of cortical bone by comparing the mechanical properties of this type of bone pre and post expose to PP and in comparison with the control samples. A positive buck-boost converter was applied to generate adjustable high voltage, high frequency pulses (up to 500 V and 10 kHz). The functional behavior of bone in response to pulse power excitation was elucidated by applying compressive loading until failure. The stiffness, failure stress (strength) and the total fracture energy (bone toughness) were determined as a measure of the main bone characteristics. Furthermore, an ultrasonic technique was applied to determine and comprise bone elasticity before and after pulse power stimulation. The elastic property of cortical bone samples appeared to remain unchanged following exposure to pulse power excitation for all three orthogonal directions obtained from ultrasonic technique and similarly from the compression test. Nevertheless, the compressive strength and toughness of bone samples were increased when they were exposed to 66 h of high power pulsed electromagnetic field compared to the control samples. As the toughness and the strength of the cortical bone tissue are directly associated with the quality and integrity of the collagen matrix whereas its stiffness is primarily related to bone mineral content these overall results may address that although, the pulse power stimulation can influence the arrangement or the quality of the collagen network

  7. Development of Voltage Regulation Plan by Composing Subsystem with the SFES for DC On-line Electric Vehicle

    Science.gov (United States)

    Jung, S.; Lee, J. H.; Yoon, M.; Lee, H.; Jang, G.

    The study of the application process of the relatively small size 'Superconducting Flywheel Energy Storage (SFES)' system is conducted to regulate voltage fluctuation of the DC On-Line Electric Vehicle (OLEV) system, which is designed by using DC power system network. It is recommended to construct the power conversion system nearby the substation because the charging system is under the low voltage. But as the system is usually built around urban area and it makes hard to construct the subsystems at every station, voltage drop can occur in power supply inverter that is some distance from the substation. As the alternative of this issue, DC distribution system is recently introduced and has possibility to solve the above issue. In this paper, SFES is introduced to solve the voltage drop under the low voltage distribution system by using the concept of the proposed DC OLEV which results in building the longer distance power supply system. The simulation to design the SFES by using DC power flow analysis is carried out and it is verified in this paper.

  8. Calculation of voltages in electric power transmission lines during historic geomagnetic storms: An investigation using realistic earth impedances

    Science.gov (United States)

    Lucas, Greg M.; Love, Jeffrey J.; Kelbert, Anna

    2018-01-01

    Commonly, one-dimensional (1-D) Earth impedances have been used to calculate the voltages induced across electric power transmission lines during geomagnetic storms under the assumption that much of the three-dimensional structure of the Earth gets smoothed when integrating along power transmission lines. We calculate the voltage across power transmission lines in the mid-Atlantic region with both regional 1-D impedances and 64 empirical 3-D impedances obtained from a magnetotelluric survey. The use of 3-D impedances produces substantially more spatial variance in the calculated voltages, with the voltages being more than an order of magnitude different, both higher and lower, than the voltages calculated utilizing regional 1-D impedances. During the March 1989 geomagnetic storm 62 transmission lines exceed 100 V when utilizing empirical 3-D impedances, whereas 16 transmission lines exceed 100 V when utilizing regional 1-D impedances. This demonstrates the importance of using realistic impedances to understand and quantify the impact that a geomagnetic storm has on power grids.

  9. Urban exposure to ELF magnetic field due to high-, medium- and low-voltage electricity supply networks.

    Science.gov (United States)

    Bottura, V; Cappio Borlino, M; Carta, N; Cerise, L; Imperial, E

    2009-12-01

    The regional environment protection agency (ARPA) of the Aosta Valley region in north Italy performed a survey of magnetic field triggered by the power supply network in high, medium and low voltages on the entire area of Aosta town. The electrical distribution system for houses was not however taken into account. The aim of the survey was to evaluate the global population exposure and not simply the assessment of the legal exposure limit compliance.

  10. Methods for calculation of undelivered electricity in medium voltage network that is not integrated into the remote control system

    Directory of Open Access Journals (Sweden)

    Vrcelj Nada

    2013-01-01

    Full Text Available The method is based on data obtained from the so-called. hand-held measuring current at 10 kV voltage level and from reports of outages at reclosers that are installed in a part of network that is observed. At first, is calculates the electrical load of the main distribution power lines, and then simulates the corresponding power flow and calculates the undelivered electricity. The method was applied to parts of the network PD ED Belgrade that are not in the remote control system and is developed for the purpose of considering the effects of automation in the 10 kV PD ED Belgrade.

  11. The investigation of an electric arc in the long cylindrical channel of the powerful high-voltage AC plasma torch

    Science.gov (United States)

    Rutberg, Ph G.; Popov, S. D.; Surov, A. V.; Serba, E. O.; Nakonechny, Gh V.; Spodobin, V. A.; Pavlov, A. V.; Surov, A. V.

    2012-12-01

    The comparison of conductivity obtained in experiments with calculated values is made in this paper. Powerful stationary plasma torches with prolonged period of continuous work are popular for modern plasmachemical applications. The maximum electrode lifetime with the minimum erosion can be reached while working on rather low currents. Meanwhile it is required to provide voltage arc drop for the high power achievement. Electric field strength in the arc column of the high-voltage plasma torch, using air as a plasma-forming gas, does not exceed 15 V/cm. It is possible to obtain the high voltage drop in the long arc stabilized in the channel by the intensive gas flow under given conditions. Models of high voltage plasma torches with rod electrodes with power up to 50 kW have been developed and investigated. The plasma torch arcs are burning in cylindrical channels. Present investigations are directed at studying the possibility of developing long arc plasma torches with higher power. The advantage of AC power supplies usage is the possibility of the loss minimization due to the reactive power compensation. The theoretical maximum of voltage arc drop for power supplies with inductive current limitations is about 50 % of the no-load voltage for a single-phase circuit and about 30 % for the three-phase circuit. Burning of intensively blown arcs in the long cylindrical channel using the AC power supply with 10 kV no-load voltage is experimentally investigated in the work. Voltage drops close to the maximum possible had been reached in the examined arcs in single-phase and three-phase modes. Operating parameters for single-phase mode were: current -30 A, voltage drop -5 kV, air flow rate 35 g/s; for three-phase mode: current (40-85) A, voltage drop (2.5-3.2) kV, air flow rate (60-100) g/s. Arc length in the installations exceeded 2 m.

  12. The digital algorithm for fast detecting and identifying the asymmetry of voltages in three-phase electric grids of mechanical engineering facilities

    Science.gov (United States)

    Shonin, O. B.; Kryltcov, S. B.; Novozhilov, N. G.

    2017-02-01

    The paper considers a new technique for the fast method of extracting symmetrical components of unbalanced voltages caused by the faults in electric grids of mechanical engineering facilities. The proposed approach is based on the iterative algorithm that checks if the set of at least three voltage discrete measurements belongs to a specific ellipse trajectory of the voltage space vector. Using classification of unbalanced faults in the grid and results of decomposing the voltages into symmetrical components, the algorithm is capable to discriminate between one-phase, two-phase and three-phase voltage sags. The paper concludes that results of simulation in Simulink environment have proved the correctness of the proposed algorithm for detecting and identifying the unbalanced voltage sags in the electrical grid under condition that it is free from high order harmonics.

  13. Project resumes: biological effects from electric fields associated with high-voltage transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-01-01

    Abstracts of research projects are presented in the following areas: measurements and special facilities; cellular and subcellular studies; physiology; behavior; environmental effects; modeling, scaling and dosimetry; and high voltage direct current. (ACR)

  14. Voltage control and protection in electrical power systems from system components to wide-area control

    CERN Document Server

    Corsi, Sandro

    2015-01-01

    Based on the author’s twenty years of experience, this book shows the practicality of modern, conceptually new, wide area voltage control in transmission and distribution smart grids, in detail. Evidence is given of the great advantages of this approach, as well as what can be gained by new control functionalities which modern technologies now available can provide. The distinction between solutions of wide area voltage regulation (V-WAR) and wide area voltage protection (V-WAP) are presented, demonstrating the proper synergy between them when they operate on the same power system as well as the simplicity and effectiveness of the protection solution in this case. The author provides an overview and detailed descriptions of voltage controls, distinguishing between generalities of underdeveloped, on-field operating applications and modern and available automatic control solutions, which are as yet not sufficiently known or perceived for what they are: practical, high-performance and reliable solutions. At th...

  15. Voltage- and current-activated metal–insulator transition in VO2-based electrical switches: a lifetime operation analysis

    Directory of Open Access Journals (Sweden)

    Aurelian Crunteanu, Julien Givernaud, Jonathan Leroy, David Mardivirin, Corinne Champeaux, Jean-Christophe Orlianges, Alain Catherinot and Pierre Blondy

    2010-01-01

    Full Text Available Vanadium dioxide is an intensively studied material that undergoes a temperature-induced metal–insulator phase transition accompanied by a large change in electrical resistivity. Electrical switches based on this material show promising properties in terms of speed and broadband operation. The exploration of the failure behavior and reliability of such devices is very important in view of their integration in practical electronic circuits. We performed systematic lifetime investigations of two-terminal switches based on the electrical activation of the metal–insulator transition in VO2 thin films. The devices were integrated in coplanar microwave waveguides (CPWs in series configuration. We detected the evolution of a 10 GHz microwave signal transmitted through the CPW, modulated by the activation of the VO2 switches in both voltage- and current-controlled modes. We demonstrated enhanced lifetime operation of current-controlled VO2-based switching (more than 260 million cycles without failure compared with the voltage-activated mode (breakdown at around 16 million activation cycles. The evolution of the electrical self-oscillations of a VO2-based switch induced in the current-operated mode is a subtle indicator of the material properties modification and can be used to monitor its behavior under various external stresses in sensor applications.

  16. Electric strength of insulation on superhigh-voltage overhead transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Danis, J.; Kromer, I.L.

    1979-09-01

    Insulation for superhigh-voltage overhead transmission lines is selected on the basis of reliability during switching overvoltages and extreme changes in ambient conditions. A study of 400 kV and 750 kV insulator strings, porcelain and glass, respectively, was made to determine their performance with dusty or moist surface under these severe conditions as expected in service. Four different configurations of a double string suspended from a cross beam 30 m above ground and at various horizontal distances from lateral poles were tested. The risetime of aperiodic voltage pulses was varied from 35 ..mu..s (below critical) to 1200..mu..s (above critical) and their duration was varied from 1000 to 10,500 ..mu..s, the voltage level changed in 5% steps and successive pulses applied in 30 to 40 s intervals. The 50%-discharge voltage was estimated by the up and down method and the readings evaluated statistically by Student's method. The results yielded the voltage-time characteristics of these insulator strings, with the dip of the 50%-discharge voltage down to its minimum critical level corresponding to an overvoltage pulse with the critical risetime. Further analysis yields also the risk and the number of flashhovers, depending on the contamination distribution density, on the overvoltage amplitude distribution density, and on the number of weak spots. Contamination increases the probable number of flashovers during switching by 30 to 50%.

  17. Measurement and Modeling of Personal Exposure to the Electric and Magnetic Fields in the Vicinity of High Voltage Power Lines.

    Science.gov (United States)

    Tourab, Wafa; Babouri, Abdesselam

    2016-06-01

    This work presents an experimental and modeling study of the electromagnetic environment in the vicinity of a high voltage substation located in eastern Algeria (Annaba city) specified with a very high population density. The effects of electromagnetic fields emanating from the coupled multi-lines high voltage power systems (MLHV) on the health of the workers and people living in proximity of substations has been analyzed. Experimental Measurements for the Multi-lines power system proposed have been conducted in the free space under the high voltage lines. Field's intensities were measured using a referenced and calibrated electromagnetic field meter PMM8053B for the levels 0 m, 1 m, 1.5 m and 1.8 m witch present the sensitive's parts as organs and major functions (head, heart, pelvis and feet) of the human body. The measurement results were validated by numerical simulation using the finite element method and these results are compared with the limit values of the international standards. We project to set own national standards for exposure to electromagnetic fields, in order to achieve a regional database that will be at the disposal of partners concerned to ensure safety of people and mainly workers inside high voltage electrical substations.

  18. Design and construction of prototype transversely excited atmospheric (TEA nitrogen laser energized by a high voltage electrical discharge

    Directory of Open Access Journals (Sweden)

    Mukhtar Hussain

    2015-07-01

    Full Text Available The present study reports design and construction, of a prototype of Transversely Excited Atmospheric (TEA nitrogen laser, and a high voltage power supply to excite N2 gas in air, while air is used as an active lasing medium. A Blumlein line discharge circuit is used for operation of this laser. The high voltage is generated by a fly back transformer based power supply varying from 10 kV to 20 kV. The wavelength (337.1 nm of TEA nitrogen laser is measured employing a standard commercial spectrometer and the laser output energy of 300 μJ is measured from the constructed system. Different parameters such as beam profile, laser output spectrum, laser efficiency, and variation of E/P (Electrical field/Pressure value with respect to input voltage and electrodes separations are studied in order to optimize the overall operational efficiency of present nitrogen laser. The analysis of the high voltage prototype appeared in this designed source has also been made and described in this paper.

  19. [Effects of flow-through descending branch of lateral circumflex femoral artery flap on repairing high-voltage electrical burn wounds of wrist of patients].

    Science.gov (United States)

    Shen, Y M; Chen, X; Zhang, C; Wang, C; Qin, F J; Ma, C X; Hu, X H

    2017-07-20

    Objective: To investigate the effects of flow-through descending branch of lateral circumflex femoral artery flap on repairing high-voltage electrical burn wounds of wrist of patients. Methods: From January 2014 to June 2016, 5 patients with high-voltage electrical burn of unilateral wrist were hospitalized in our burn ward, with extensive necrosis of skin soft tissue of burn wrist. Five patients were transferred to our burn ward 6 to 12 days post injury after undergoing emergency dermotomy of wrist to reduce tension in other hospitals. In 2 to 3 days after admission, operation was performed by two surgeon group at the same time, when patients' general condition were stable. One group underwent debridement and the other group designed and dissected flap according to the range of skin soft tissue defect of wrist. Wrist wounds after debridement ranged from 15 cm×10 cm to 24 cm×15 cm. Three patients were treated with flow-through descending branch of lateral circumflex femoral artery flap and great saphenous vein for repairing wounds of wrist and reconstruction of ulnar and radial artery. Two patients were treated with flow-through descending branch of lateral circumflex femoral artery flap for repairing wounds of wrist and reconstruction of ulnar artery. The dissected flaps ranged from 16 cm×12 cm to 26 cm×16 cm and the length of bridging vessel ranged from 15 to 21 cm. Results: The flow-through descending branch of lateral circumflex femoral artery flaps of five patients survived well. Wounds of 4 patients healed and wounds of 1 patient with infection under the flap on 3 days after operation healed after changing wound dressing and undergoing debridement for 2 weeks. After the operation, wrists and hands of 5 patients had adequate blood supply and ulnar and radial artery recovered patency. Follow-up of patients for 6 months to 1 year showed good flap appearance and adequate blood supply of burn hands. Conclusions: The flow-through descending branch of lateral

  20. Evaluation of the effectiveness of neurofeedback in the reduction of Posttraumatic stress disorder (PTSD) in a patient following high-voltage electric shock with the use of ERPs.

    Science.gov (United States)

    Chrapusta, Anna; Pąchalska, Maria; Wilk-Frańczuk, Magdalena; Starczyńska, Małgorzata; Kropotov, Juri D

    2015-01-01

    The aim of our research was an evaluation of the effectiveness of neurofeedback in reducing the symptoms of Post-trauma stress disorder (PTSD), which had developed as a result of a high-voltage electric burn to the head. Quantitative EEG (QEEG) and Event related potentials (ERPs) were utilised in the evaluation. A 21-year-old patient, experienced 4(th) degree burns to his head as a result of a high-voltage electric burn. The patient was repeatedly operated on and despite the severity of the injuries was to recover. However the patient complained of flashbacks, difficulties with sleeping as well as an inability to continue work in his given profession. Specialist tests were to show the presence within him of PTSD. As a result of which the patient was provided with neurofeedback therapy. The effectiveness of this therapy in the reduction (eradication) of the symptoms of PTSD were evaluated through the utilisation of qantitative eeg (Qeeg) and event related potentials (ERPs). It was found that in the first examination that ERPs display the most significant deviations from the reference in the two components: (1) the one component is generated within the cingulate cortex. The pattern of its deviation from the norms is similar to that found in a group of OCD patients. In contrast to healthy subjects the component repeats itself twice; (2) the second component is generated in the medial prefrontal cortex. Its pattern (neuromarker) is similar to that found in PTSD patients. There is a delay in the late part of the component, which probably reflects the flashbacks. In the second examination, after neurofeedback training, the ERPs were similar to the norm. The patient returned to work. Chronic PTSD developed within the patient as a result of a high-voltage electric burn. The application of a method of therapy (neurofeedback) resulted in the withdrawal of the syndrome symptoms. ERPs in a GO/NOGO task can be used to plan neurofeedback and in the assessment of functional brain

  1. Construction and use of a zebrafish heart voltage and calcium optical mapping system, with integrated electrocardiogram and programmable electrical stimulation

    Science.gov (United States)

    Lin, Eric; Craig, Calvin; Lamothe, Marcel; Sarunic, Marinko V.; Beg, Mirza Faisal

    2015-01-01

    Zebrafish are increasingly being used as a model of vertebrate cardiology due to mammalian-like cardiac properties in many respects. The size and fecundity of zebrafish make them suitable for large-scale genetic and pharmacological screening. In larger mammalian hearts, optical mapping is often used to investigate the interplay between voltage and calcium dynamics and to investigate their respective roles in arrhythmogenesis. This report outlines the construction of an optical mapping system for use with zebrafish hearts, using the voltage-sensitive dye RH 237 and the calcium indicator dye Rhod-2 using two industrial-level CCD cameras. With the use of economical cameras and a common 532-nm diode laser for excitation, the rate dependence of voltage and calcium dynamics within the atrial and ventricular compartments can be simultaneously determined. At 140 beats/min, the atrial action potential duration was 36 ms and the transient duration was 53 ms. With the use of a programmable electrical stimulator, a shallow rate dependence of 3 and 4 ms per 100 beats/min was observed, respectively. In the ventricle the action potential duration was 109 ms and the transient duration was 124 ms, with a steeper rate dependence of 12 and 16 ms per 100 beats/min. Synchronous electrocardiograms and optical mapping recordings were recorded, in which the P-wave aligns with the atrial voltage peak and R-wave aligns with the ventricular peak. A simple optical pathway and imaging chamber are detailed along with schematics for the in-house construction of the electrocardiogram amplifier and electrical stimulator. Laboratory procedures necessary for zebrafish heart isolation, cannulation, and loading are also presented. PMID:25740339

  2. Multilevel-Dc-Bus Inverter For Providing Sinusoidal And Pwm Electrical Machine Voltages

    Science.gov (United States)

    Su, Gui-Jia [Knoxville, TN

    2005-11-29

    A circuit for controlling an ac machine comprises a full bridge network of commutation switches which are connected to supply current for a corresponding voltage phase to the stator windings, a plurality of diodes, each in parallel connection to a respective one of the commutation switches, a plurality of dc source connections providing a multi-level dc bus for the full bridge network of commutation switches to produce sinusoidal voltages or PWM signals, and a controller connected for control of said dc source connections and said full bridge network of commutation switches to output substantially sinusoidal voltages to the stator windings. With the invention, the number of semiconductor switches is reduced to m+3 for a multi-level dc bus having m levels. A method of machine control is also disclosed.

  3. Four-point probe measurements using current probes with voltage feedback to measure electric potentials

    Science.gov (United States)

    Lüpke, Felix; Cuma, David; Korte, Stefan; Cherepanov, Vasily; Voigtländer, Bert

    2018-02-01

    We present a four-point probe resistance measurement technique which uses four equivalent current measuring units, resulting in minimal hardware requirements and corresponding sources of noise. Local sample potentials are measured by a software feedback loop which adjusts the corresponding tip voltage such that no current flows to the sample. The resulting tip voltage is then equivalent to the sample potential at the tip position. We implement this measurement method into a multi-tip scanning tunneling microscope setup such that potentials can also be measured in tunneling contact, allowing in principle truly non-invasive four-probe measurements. The resulting measurement capabilities are demonstrated for \

  4. Controlled Operation of the Islanded Portion of the International Council on Large Electric Systems (CIGRE Low Voltage Distribution Network

    Directory of Open Access Journals (Sweden)

    Ghullam Mustafa Bhutto

    2017-07-01

    Full Text Available In islanding, a portion of the power network, comprised of the loads and distributed generation (DG units, is isolated from the rest of the power grid and forms a micro grid (MG. In this condition, it becomes essential for the islanded MG to operate in a stable and controlled manner by providing ancillary services. When the MG is cut off from the main grid, the islanding must be detected by the DG units. In this condition it is essential that one of the controllers should be switched to the voltage-frequency (VF control mode. In islanding, the network loses it slack reference and this reference is established by a VF controller. The voltage and the frequency of the islanded MG deviate when disconnected from the transmission grid and these deviations are caused by the load-generation imbalance. The voltage and the frequency of the islanded MG can be restored to the permissible limits if the desired/exceeded amount of active and reactive power is injected/absorbed by the locally available sources in islanded MG. This paper proposes a control strategy which can compensate the voltage and the frequency deviations in the islanded portion of the International Council on Large Electric Systems (CIGRE low voltage distribution network by using advanced power electronics devices such as STATCOMs for Photovoltaic (PV Units and Battery Energy Storage Systems (BESS STATCOMs (for battery units. The selection of the VF controller for the most suitable DG unit of this test network is also presented in this paper, and the effectiveness of the controllers is verified by presenting simulation results using DIgSILENT (DIgSILENT GmbH, Gomaringen, Germany power factory software version 15.0.

  5. Frequency and voltage dependence dielectric properties, ac electrical conductivity and electric modulus profiles in Al/Co{sub 3}O{sub 4}-PVA/p-Si structures

    Energy Technology Data Exchange (ETDEWEB)

    Bilkan, Çiğdem, E-mail: cigdembilkan@gmail.com [Department of Physics, Faculty of Sciences, The University of Çankırı Karatekin, 18100 Çankırı (Turkey); Azizian-Kalandaragh, Yashar [Department of Physics, Faculty of Science, The University of Mohaghegh Ardabili, Ardabil (Iran, Islamic Republic of); Altındal, Şemsettin [Department of Physics, Faculty of Sciences, The University of Gazi, 06500 Ankara (Turkey); Shokrani-Havigh, Roya [Department of Physics, Faculty of Science, The University of Mohaghegh Ardabili, Ardabil (Iran, Islamic Republic of)

    2016-11-01

    In this research a simple microwave-assisted method have been used for preparation of cobalt oxide nanostructures. The as-prepared sample has been investigated by UV–vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM). On the other hand, frequency and voltage dependence of both the real and imaginary parts of dielectric constants (ε′, ε″) and electric modulus (M′ and M″), loss tangent (tanδ), and ac electrical conductivity (σ{sub ac}) values of Al/Co{sub 3}O{sub 4}-PVA/p-Si structures were obtained in the wide range of frequency and voltage using capacitance (C) and conductance (G/ω) data at room temperature. The values of ε′, ε″ and tanδ were found to decrease with increasing frequency almost for each applied bias voltage, but the changes in these parameters become more effective in the depletion region at low frequencies due to the charges at surface states and their relaxation time and polarization effect. While the value of σ is almost constant at low frequency, increases almost as exponentially at high frequency which are corresponding to σ{sub dc} and σ{sub ac}, respectively. The M′ and M″ have low values at low frequencies region and then an increase with frequency due to short-range mobility of charge carriers. While the value of M′ increase with increasing frequency, the value of M″ shows two peak and the peaks positions shifts to higher frequency with increasing applied voltage due to the decrease of the polarization and N{sub ss} effects with increasing frequency.

  6. Electric Boiler and Heat Pump Thermo-Electrical Models for Demand Side Management Analysis in Low Voltage Grids

    DEFF Research Database (Denmark)

    Diaz de Cerio Mendaza, Iker; Bak-Jensen, Birgitte; Chen, Zhe

    2013-01-01

    The last fifteen years many European countries have integrated large percentage of renewable energy on their electricity generation mix. In Denmark the 21.3% of the electricity consumed nowadays is produced by the wind, and it has planned to be the 50% by 2025. In order to front future challenges...... as active loads. The models were simulated under different Danish daily domestic hot water and space heating profiles. Results showed that under high heating demand conditions the flexibility of this kind of units may be drastically restricted due to their continuous operation....... on the power system control and operation, created by this unstable way of generation, Demand Side Management turns to be a promising solution. The storage capacity from thermo-electric units, like electric boilers and heat pumps, allows operating them with certain freedom. Hence they can be employed under...

  7. Functional electrical stimulation in spinal cord injury respiratory care.

    Science.gov (United States)

    Jarosz, Renata; Littlepage, Meagan M; Creasey, Graham; McKenna, Stephen L

    2012-01-01

    The management of chronic respiratory insufficiency and/or long-term inability to breathe independently has traditionally been via positive-pressure ventilation through a mechanical ventilator. Although life-sustaining, it is associated with limitations of function, lack of independence, decreased quality of life, sleep disturbance, and increased risk for infections. In addition, its mechanical and electronic complexity requires full understanding of the possible malfunctions by patients and caregivers. Ventilator-associated pneumonia, tracheal injury, and equipment malfunction account for common complications of prolonged ventilation, and respiratory infections are the most common cause of death in spinal cord-injured patients. The development of functional electric stimulation (FES) as an alternative to mechanical ventilation has been motivated by a goal to improve the quality of life of affected individuals. In this article, we will review the physiology, types, characteristics, risks and benefits, surgical techniques, and complications of the 2 commercially available FES strategies - phrenic nerve pacing (PNP) and diaphragm motor point pacing (DMPP).

  8. Electrical Neuromodulation of the Respiratory System After Spinal Cord Injury.

    Science.gov (United States)

    Hachmann, Jan T; Grahn, Peter J; Calvert, Jonathan S; Drubach, Dina I; Lee, Kendall H; Lavrov, Igor A

    2017-09-01

    Spinal cord injury (SCI) is a complex and devastating condition characterized by disruption of descending, ascending, and intrinsic spinal circuitry resulting in chronic neurologic deficits. In addition to limb and trunk sensorimotor deficits, SCI can impair autonomic neurocircuitry such as the motor networks that support respiration and cough. High cervical SCI can cause complete respiratory paralysis, and even lower cervical or thoracic lesions commonly result in partial respiratory impairment. Although electrophrenic respiration can restore ventilator-independent breathing in select candidates, only a small subset of affected individuals can benefit from this technology at this moment. Over the past decades, spinal cord stimulation has shown promise for augmentation and recovery of neurologic function including motor control, cough, and breathing. The present review discusses the challenges and potentials of spinal cord stimulation for restoring respiratory function by overcoming some of the limitations of conventional respiratory functional electrical stimulation systems. Copyright © 2017 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  9. Electric vehicles in low voltage residential grid: a danish case study

    DEFF Research Database (Denmark)

    Pillai, Jayakrishnan Radhakrishna; Huang, Shaojun; Thøgersen, Paul

    2012-01-01

    Electric Vehicles (EVs) have gained large interest in the energy sector as a carrier to support clean transportation and green electricity. The potential to use battery storages of electric vehicles as a sink for excess electricity that may result from large integration of wind power, especially...... in countries like Denmark, is widely discussed and promoted. However, the wide-spread adoption of EVs requires the provision of intelligent grid and EV charging infrastructure. To analyse and understand the amount of EVs that could be integrated in the local distribution grids, within its existing capabilities...

  10. Proposal and Development of a High Voltage Variable Frequency Alternating Current Power System for Hybrid Electric Aircraft

    Science.gov (United States)

    Sadey, David J.; Taylor, Linda M.; Beach, Raymond F.

    2017-01-01

    The development of ultra-efficient commercial vehicles and the transition to low-carbon emission propulsion are seen as strategic thrust paths within NASA Aeronautics. A critical enabler to these paths comes in the form of hybrid electric propulsion systems. For megawatt-class systems, the best power system topology for these hybrid electric propulsion systems is debatable. Current proposals within NASA and the Aero community suggest using a combination of alternating current (AC) and direct current (DC) for power generation, transmission, and distribution. This paper proposes an alternative to the current thought model through the use of a primarily high voltage AC power system, supported by the Convergent Aeronautics Solutions (CAS) Project. This system relies heavily on the use of doubly-fed induction machines (DFIMs), which provide high power densities, minimal power conversion, and variable speed operation. The paper presents background on the activity along with the system architecture, development status, and preliminary results.

  11. Concurrent Provision of Frequency Regulation and Overvoltage Support by Electric Vehicles in a Real Danish Low Voltage Network

    DEFF Research Database (Denmark)

    Knezovic, Katarina; Marinelli, Mattia; Andersen, Peter Bach

    2014-01-01

    Expected deployment of electric vehicles (EVs) introduces big technical challenges for power system operation, but also offers advantages provided that EVs are not considered merely as passive loads. With the development of Vehicle-to-Grid technology, EVs will be able to provide a number of ancil......Expected deployment of electric vehicles (EVs) introduces big technical challenges for power system operation, but also offers advantages provided that EVs are not considered merely as passive loads. With the development of Vehicle-to-Grid technology, EVs will be able to provide a number...... of ancillary services for grid support, e.g. implemented electronic equipment will allow them to exchange reactive power with the grid for voltage regulation while using active power for other services. This paper investigates the concurrent provision of local and system wide services from EVs in a real Danish...

  12. Three-dimensional modelling of electric-arc development in a low-voltage circuit-breaker

    Energy Technology Data Exchange (ETDEWEB)

    Piqueras, L.; Henry, D.; Jeandel, D.; Scott, J. [Laboratoire de Mecanique des Fluides et d' Acoustique, CNRS/Universite de Lyon, Ecole Centrale de Lyon/Universite Lyon 1/INSA de Lyon, ECL, 36 avenue Guy de Collongue, 69134 Ecully Cedex (France); Wild, J. [Schneider Electric, 37 quai Merlin, 38050 Grenoble Cedex 9 (France)

    2008-09-15

    This article describes direct numerical simulation of the first three milliseconds following ignition of the arc in a low-voltage circuit-breaker using a computational-fluid-dynamics code adapted for electric-arc modelling. The mobile electrode is allowed for by a moving mesh. The results describe the evolution of the arc with time in terms of its detailed electrical, thermal and fluid dynamic properties. They allow the identification of several phases during the overall arc development process studied here: arc initialisation in the widening electrode gap, arc-thermal expansion, displacement of the arc towards the tip of the mobile electrode, and the beginning of commutation to the fixed electrode. (author)

  13. Load control in low voltage level of the electricity grid using µCHP appliances

    NARCIS (Netherlands)

    Bosman, M.G.C.; Bakker, Vincent; Molderink, Albert; Hurink, Johann L.; Smit, Gerardus Johannes Maria

    2008-01-01

    The introduction of microCHP (Combined Heat and Power) appliances and other means of distributed generation causes a shift in the way electricity is produced and consumed. Households themselves produce electricity and deliver the surplus to the grid. In this way, the distributed generation also has

  14. The Electrostatic Wind Energy Converter : Electrical performance of a high voltage prototype

    NARCIS (Netherlands)

    Djairam, D.

    2008-01-01

    Wind energy is converted to electrical energy by letting the wind move charged particles against the direction of an electric field. The advantage of this type of conversion is that no rotational movement, which occurs in conventional wind turbines, is required. An electrostatic wind energy

  15. Development of a High-Speed Current Injection and Voltage Measurement System for Electrical Impedance Tomography-Based Stretchable Sensors

    Directory of Open Access Journals (Sweden)

    Stefania Russo

    2017-07-01

    Full Text Available Electrical impedance tomography (EIT is an imaging method that can be applied over stretchable conductive-fabric materials to realize soft and wearable pressure sensors through current injections and voltage measurements at electrodes placed at the boundary of a conductive medium. In common EIT systems, the voltage data are serially measured by means of multiplexers, and are hence collected at slightly different times, which affects the real-time performance of the system. They also tend to have complicated hardware, which increases power consumption. In this paper, we present our design of a 16-electrode high-speed EIT system that simultaneously implements constant current injection and differential potential measurements. This leads to a faster, simpler-to-implement and less-noisy technique, when compared with traditional EIT approaches. Our system consists of a Howland current pump with two multiplexers for a constant DC current supply, and a data acquisition card. It guarantees a data collection rate of 78 frames/s. The results from our conductive stretchable fabric sensor show that the system successfully performs voltage data collection with a mean signal-to-noise ratio (SNR of 55 dB, and a mean absolute deviation (MAD of 0.5 mV. The power consumption can be brought down to 3 mW; therefore, it is suitable for battery-powered applications. Finally, pressure contacts over the sensor are properly reconstructed, thereby validating the efficiency of our EIT system for soft and stretchable sensor applications.

  16. Low voltage electric potential as a driving force to hinder biofouling in self-supporting carbon nanotube membranes.

    Science.gov (United States)

    Thamaraiselvan, Chidambaram; Ronen, Avner; Lerman, Sofia; Balaish, Moran; Ein-Eli, Yair; Dosoretz, Carlos G

    2017-11-03

    This study aimed at evaluating the contribution of low voltage electric field, both alternating (AC) and direct (DC) currents, on the prevention of bacterial attachment and cell inactivation to highly electrically conductive self-supporting carbon nanotubes (CNT) membranes at conditions which encourage biofilm formation. A mutant strain of Pseudomonas putida S12 was used a model bacterium and either capacitive or resistive electrical circuits and two flow regimes, flow-through and cross-flow filtration, were studied. Major emphasis was placed on AC due to its ability of repulsing and inactivating bacteria. AC voltage at 1.5 V, 1 kHz frequency and wave pulse above offset (+0.45) with 100Ω external resistance on the ground side prevented almost completely attachment of bacteria (>98.5%) with concomitant high inactivation (95.3 ± 2.5%) in flow-through regime. AC resulted more effective than DC, both in terms of biofouling reduction compared to cathodic DC and in terms of cell inactivation compared to anodic DC. Although similar trends were observed, a net reduced extent of prevention of bacterial attachment and inactivation was observed in filtration as compared to flow-through regime, which is mainly attributed to the permeate drag force, also supported by theoretical calculations in DC in capacitive mode. Electrochemical impedance spectroscopy analysis suggests a pure resistor behavior in resistance mode compared to involvement of redox reactions in capacitance mode, as source for bacteria detachment and inactivation. Although further optimization is required, electrically polarized CNT membranes offer a viable antibiofouling strategy to hinder biofouling and simplify membrane care during filtration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Voltage-stabilised elastomers with increased relative permittivity and high electrical breakdown strength by means of phase separating binary copolymer blends of silicone elastomers

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Yu, Liyun; Skov, Anne Ladegaard

    2017-01-01

    Increased electrical breakdown strength and increased dielectric permittivity of silicone-based dielectric elastomers are achieved by means of the addition of so-called voltage-stabilisers prepared from PDMS–PPMS copolymers as well as PDMS–PEG copolymers in order to compensate for the negative...... effect of softness on electrical stability of silicone elastomers. The voltage-stabilised elastomer, incorporating a high-permittivity PDMS–PEG copolymer, possesses increased relative permittivity, high electrical breakdown strength, excellent network integrity and low dielectric loss and paves the way...

  18. Public magnetic field exposure based on internal current density for electric low voltage systems.

    Science.gov (United States)

    Keikko, Tommi; Seesvuori, Reino; Hyvönen, Martti; Valkealahti, Seppo

    2009-04-01

    A measurement concept utilizing a new magnetic field exposure metering system has been developed for indoor substations where voltage is transformed from a medium voltage of 10 or 20 kV to a low voltage of 400 V. The new metering system follows the guidelines published by the International Commission on Non-Ionizing Radiation Protection. It can be used to measure magnetic field values, total harmonic distortion of the magnetic field, magnetic field exposure ratios for public and workers, load current values, and total harmonic distortion of the load current. This paper demonstrates how exposure to non-sinusoidal magnetic fields and magnetic flux density exposure values can be compared directly with limit values for internal current densities in a human body. Further, we present how the magnetic field and magnetic field exposure behaves in the vicinity of magnetic field sources within the indoor substation and in the neighborhood. Measured magnetic fields around the substation components have been used to develop a measurement concept by which long-term measurements in the substations were performed. Long-term measurements revealed interesting and partly unexpected dependencies between the measured quantities, which have been further analyzed. The principle of this paper is to substitute a demanding exposure measurement with measurements of the basic quantities like the 50 Hz fundamental magnetic field component, which can be estimated based on the load currents for certain classes of substation lay-out.

  19. Experimental and numerical study of impact of voltage fluctuate, flicker and power factor wave electric generator to local distribution

    Science.gov (United States)

    Hadi, Nik Azran Ab; Rashid, Wan Norhisyam Abd; Hashim, Nik Mohd Zarifie; Mohamad, Najmiah Radiah; Kadmin, Ahmad Fauzan

    2017-10-01

    Electricity is the most powerful energy source in the world. Engineer and technologist combined and cooperated to invent a new low-cost technology and free carbon emission where the carbon emission issue is a major concern now due to global warming. Renewable energy sources such as hydro, wind and wave are becoming widespread to reduce the carbon emissions, on the other hand, this effort needs several novel methods, techniques and technologies compared to coal-based power. Power quality of renewable sources needs in depth research and endless study to improve renewable energy technologies. The aim of this project is to investigate the impact of renewable electric generator on its local distribution system. The power farm was designed to connect to the local distribution system and it will be investigated and analyzed to make sure that energy which is supplied to customer is clean. The MATLAB tools are used to simulate the overall analysis. At the end of the project, a summary of identifying various voltage fluctuates data sources is presented in terms of voltage flicker. A suggestion of the analysis impact of wave power generation on its local distribution is also presented for the development of wave generator farms.

  20. Monitoring of recruitment and derecruitment by electrical impedance tomography in a model of acute lung injury

    NARCIS (Netherlands)

    Kunst, P. W.; Vazquez de Anda, G.; Böhm, S. H.; Faes, T. J.; Lachmann, B.; Postmus, P. E.; de Vries, P. M.

    2000-01-01

    OBJECTIVE: To evaluate a noninvasive system for obtaining information about alveolar recruitment and derecruitment in a model of acute lung injury. DESIGN: Prospective experimental study. SETTING: Animal research laboratory. SUBJECTS: Nine anesthetized pigs. INTERVENTIONS: Electrical impedance

  1. Effect of Voltage Measurement on the Quantitative Identification of Transverse Cracks by Electrical Measurements

    KAUST Repository

    Selvakumaran, Lakshmi

    2016-03-24

    Electrical tomography can be used as a structural health monitoring technique to identify different damage mechanisms in composite laminates. Previous work has established the link between transverse cracking density and mesoscale conductivity of the ply. Through the mesoscale relationship, the conductivity obtained from electrical tomography can be used as a measure of the transverse cracking density. Interpretation of this measure will be accurate provided the assumptions made during homogenization are valid. One main assumption of mesoscale homogenization is that the electric field is in the plane. Here, we test the validity of this assumption for laminates with varying anisotropy ratios and for different distances between the cracked ply and surface that is instrumented with electrodes. We also show the equivalence in electrical response between measurements from cracked laminates and their equivalent mesoscale counterparts. Finally, we propose some general guidelines on the measurement strategy for maximizing the accuracy of transverse cracks identification.

  2. OPTIMAL CHARGING OF ELECTRICAL VEHICLES IN THE SMART CITY FOR LOSS MINIMIZATION AND VOLTAGE IMPROVEMENT

    National Research Council Canada - National Science Library

    Adrian Toni Radu; Mircea Eremia; Lucian Toma

    2017-01-01

    ... than 70% of people will live in cities (World Health Organization, 2014). The urban transformation has become a major contributor to economic, demographic, social and environmental change. Electric vehicles (EVs...

  3. Determination of threshold and maximum operating electric stresses for selected high voltage insulations. Task III. Investigation of high voltage capacitor insulation. Progress report No. 4

    Energy Technology Data Exchange (ETDEWEB)

    Sosnowski, M.; Eager, G.S. Jr.

    1984-03-01

    This report covers the investigation of threshold voltage of capacitor insulation. The experimental work was performed on samples prepared from commercial polypropylene insulated, liquid-filled capacitors. The samples were vacuum-impregnated with the original capacitor insulating liquid obtained from the manufacturer. A limited number of full-size capacitor elements also were tested. Impulse voltage breakdown tests with dc voltage prestressing were performed at room temperature and 75/sup 0/C. From the results of these tests, the threshold voltage of the samples of the capacitor insulation was determined at both temperatures and that of the whole capacitor elements at room temperature. The threshold voltage of the capacitor insulation was found to be approximately equal to the impulse breakdown voltage. No difference was found between the threshold voltage at room temperature and at 75/sup 0/C. The threshold voltage of the whole capacitor elements at room temperature was found to be equal to approximately 80% of the threshold voltage of the capacitor insulation samples.

  4. Planning Future Electric Vehicle Central Charging Stations Connected to Low-Voltage Distribution Networks

    DEFF Research Database (Denmark)

    Marra, Francesco; Træholt, Chresten; Larsen, Esben

    2012-01-01

    A great interest is recently paid to Electric Vehicles (EV) and their integration into electricity grids. EV can potentially play an important role in power system operation, however, the EV charging infrastructures have been only partly defined, considering them as limited to individual charging...... grids. The option of DC fast-charging is only possible in the larger capacity grids, withstanding the parallel charge of one or two vehicles....

  5. Effects of low-voltage electrical stimulation and rapid chilling on meat quality characteristics of Chinese Yellow crossbred bulls.

    Science.gov (United States)

    Li, C B; Chen, Y J; Xu, X L; Huang, M; Hu, T J; Zhou, G H

    2010-04-22

    In this study, the effects of low-voltage electrical stimulation (LVES) and rapid chilling (RC) treatments on the quality characteristics of beef carcasses were evaluated, including the rate of pH and temperature decline, evaporative loss of carcasses, purge loss, cooking loss, and shear force values of m. longissimus steaks. Each carcass of 28 Chinese Yellow crossbred (SimmentalxYanbian) bulls was subjected to one of the four treatments, i.e., electrical stimulation and conventional chilling (ES/NR), electrical stimulation and rapid chilling (ES/RC), no electrical stimulation and rapid chilling (NE/RC), or no electrical stimulation and conventional chilling (NE/NR). Carcass pH and temperature were measured at 1, 3, 5, 7, 9, 11, and 24h post-mortem. After that, a 2.5-cm-thick m. longissimus steak was taken from the right side of each carcass and used for analyses of purge loss, cooking loss and Warner-Bratzler shear force (WBSF). The results showed that LVES accelerated the rate of carcass pH decline (Pchilling increased the rate of carcass temperature decline (P0.05). Mean purge losses for m. longissimus steaks from rapidly chilled carcasses were lower (Pchilled carcasses. Electrical stimulation had no impact on m. longissimus steak purge losses (P>0.05). Rapid chilling significantly decreased (Pchilled carcasses, but had no effect under the procedure of pre-rigor rapid chilling (P>0.05). The lowest mean shear force value was found for the ES/NR-treated m. longissimus steaks, whilst the highest one for the NE/RC-treated carcasses (Pchilling. Copyright © 2005. Published by Elsevier Ltd.

  6. Early applied electric field stimulation attenuates secondary apoptotic responses and exerts neuroprotective effects in acute spinal cord injury of rats.

    Science.gov (United States)

    Zhang, C; Zhang, G; Rong, W; Wang, A; Wu, C; Huo, X

    2015-04-16

    Injury potential, which refers to a direct current voltage between intact and injured nerve ends, is mainly caused by injury-induced Ca2+ influx. Our previous studies revealed that injury potential increased with the onset and severity of spinal cord injury (SCI), and an application of applied electric field stimulation (EFS) with the cathode distal to the lesion could delay and attenuate injury potential formation. As Ca2+ influx is also considered as a major trigger for secondary injury after SCI, we hypothesize that EFS would protect an injured spinal cord from secondary injury and consequently improve functional and pathological outcomes. In this study, rats were divided into three groups: (1) sham group, laminectomy only; (2) control group, subjected to SCI only; and (3) EFS group, received EFS immediately post-injury with the injury potential modulated to 0±0.5 mV by EFS. Functional recovery of the hind limbs was assessed using the Basso, Beattie, and Bresnahan (BBB) locomotor scale. Results revealed that EFS-treated rats exhibited significantly better locomotor function recovery. Luxol fast blue staining was performed to assess the spared myelin area. Immunofluorescence was used to observe the number of myelinated nerve fibers. Ultrastructural analysis was performed to evaluate the size of myelinated nerve fibers. Findings showed that the EFS group rats exhibited significantly less myelin loss and had larger and more myelinated nerve fibers than the control group rats in dorsal corticospinal tract (dCST) 8 weeks after SCI. Furthermore, we found that EFS inhibited the activation of calpain and caspase-3, as well as the expression of Bax, as detected by Western blot analysis. Moreover, EFS decreased cellular apoptosis, as measured by TUNEL, within 4 weeks post-injury. Results suggest that early EFS could significantly reduce spinal cord degeneration and improve functional and historical recovery. Furthermore, these neuroprotective effects may be related to

  7. Effects of acute selective pudendal nerve electrical stimulation after simulated childbirth injury

    Science.gov (United States)

    Gill, Bradley C.; Dissaranan, Charuspong; Zutshi, Massarat; Balog, Brian M.; Lin, Danli; Damaser, Margot S.

    2013-01-01

    During childbirth, a combinatorial injury occurs and can result in stress urinary incontinence (SUI). Simulated childbirth injury, consisting of vaginal distension (VD) and pudendal nerve crush (PNC), results in slowed recovery of continence, as well as decreased expression of brain-derived neurotrophic factor (BDNF), a regenerative cytokine. Electrical stimulation has been shown to upregulate BDNF in motor neurons and facilitate axon regrowth through the increase of βII-tubulin expression after injury. In this study, female rats underwent selective pudendal nerve motor branch (PNMB) stimulation after simulated childbirth injury or sham injury to determine whether such stimulation affects bladder and anal function after injury and whether the stimulation increases BDNF expression in Onuf's nucleus after injury. Rats received 4 h of VD followed by bilateral PNC and 1 h of subthreshold electrical stimulation of the left PNMB and sham stimulation of the right PNMB. Rats underwent filling cystometry and anal pressure recording before, during, and after the stimulation. Bladder and anal contractile function were partially disrupted after injury. PNMB stimulation temporarily inhibited bladder contraction after injury. Two days and 1 wk after injury, BDNF expression in Onuf's nucleus of the stimulated side was significantly increased compared with the sham-stimulated side, whereas βII-tubulin expression in Onuf's nucleus of the stimulated side was significantly increased only 1 wk after injury. Acute electrical stimulation of the pudendal nerve proximal to the crush site upregulates BDNF and βII-tubulin in Onuf's nucleus after simulated childbirth injury, which could be a potential preventive option for SUI after childbirth injury. PMID:23152293

  8. Optical and Electrical Performance of MOS-Structure Silicon Solar Cells with Antireflective Transparent ITO and Plasmonic Indium Nanoparticles under Applied Bias Voltage

    Directory of Open Access Journals (Sweden)

    Wen-Jeng Ho

    2016-08-01

    Full Text Available This paper reports impressive improvements in the optical and electrical performance of metal-oxide-semiconductor (MOS-structure silicon solar cells through the incorporation of plasmonic indium nanoparticles (In-NPs and an indium-tin-oxide (ITO electrode with periodic holes (perforations under applied bias voltage. Samples were prepared using a plain ITO electrode or perforated ITO electrode with and without In-NPs. The samples were characterized according to optical reflectance, dark current voltage, induced capacitance voltage, external quantum efficiency, and photovoltaic current voltage. Our results indicate that induced capacitance voltage and photovoltaic current voltage both depend on bias voltage, regardless of the type of ITO electrode. Under a bias voltage of 4.0 V, MOS cells with perforated ITO and plain ITO, respectively, presented conversion efficiencies of 17.53% and 15.80%. Under a bias voltage of 4.0 V, the inclusion of In-NPs increased the efficiency of cells with perforated ITO and plain ITO to 17.80% and 16.87%, respectively.

  9. Electrical and structural R&D activities on high voltage dc solid insulator in vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Pilan, N., E-mail: nicola.pilan@igi.cnr.it [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); Marcuzzi, D.; Rizzolo, A.; Grando, L.; Gambetta, G. [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); Rosa, S. Dalla [Umicore – Italbras S.p.A., Strada del Balsego, n.6, 36100 Vicenza (Italy); Kraemer, V.; Quirmbach, T. [FRIATEC Ceramics Division, Steinzeugstrasse 50, 68229 Mannheim (Germany); Chitarin, G. [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); Gobbo, R.; Pesavento, G. [DII, Università di Padova, v. Gradenigo 6/A, I-35131 Padova (Italy); De Lorenzi, A.; Lotto, L.; Rizzieri, R.; Fincato, M.; Romanato, L.; Trevisan, L.; Cervaro, V.; Franchin, L. [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy)

    2015-10-15

    Highlights: • A thorough R&D activity on the MITICA post insulator prototypes is being carried out. • The design has been numerically verified considering both mechanical and electrical aspects. • Experimental validation has been started, with positive results in both involved fields. • Alternative design solutions thickness have been proposed and successfully tested. - Abstract: This paper describes the R&D work performed in support of the design of the alumina insulators for the MITICA Neutral Beam Injector. The ceramic insulators are critical elements, both from the structural and electrical point of view, of the 1 MV electrostatic accelerator of the MITICA injector, as they are required to sustain both the mechanical loads due to the cantilevered weight of the ion source and the high electric field between the accelerator grids. This paper presents the results of numerical simulations and experimental tests on prototypes that have been carried out to validate the insulator design under realistic operating conditions.

  10. INFLUENCE OF SHOCK VOLTAGE FROM THE ELECTRIC DISCHARGE ON THE FATIGUE ENDURANCE OF CARBON STEEL IN WATER

    Directory of Open Access Journals (Sweden)

    I. O. Vakulenko

    2015-09-01

    Full Text Available Purpose. The research supposes the explanation of influence of stress impulses from an electrical discharge in water on the level of the limited endurance at a cyclic loading of the thermally work-hardened carbon steel. Methodology. Material for research was steel 45 (0,45 % carbon with сoncentration of chemical elements within the limits of steel composition. Specimens for tests are made as plates in 1 thick, width 15 and length 120-180 mm. The structural state of steel corresponded to quenching on a martensite from the normal temperatures of annealing and tempering at 300C, duration of 1 h. Microstructure was investigated with the use of electronic microscopy, the density of dislocations was estimated on the methods of X-ray analysis. Hardness was measured on the method of Rockwell (scale of «C». A cyclic loading was carried out in the conditions of symmetric bend on a tester «Saturn-10» at a temperature +20C. The treatment by shock voltage from the electrical discharge was carried out in water on setting of bath type «Iskra-23», used for cleaning of castings manufactures. Electric impulses were formed at 15-18 kV with energy of 10-12 kJ and amplitude of 1-2 GPа. Findings. As a result of processing pulses of a pressure wave of heat-strengthened steel 45 found the increase of endurance under the cyclic loading corresponds to an increased amount of accumulated dislocations on the fracture surface. The use of Coffin–Manson Equation allowed finding the decrease of deformation per cycle of loading as a result of arising stress from an electrical discharge in water. On the fracture surface (after pulse exposure was found the increased number of dislocations, located in different crystallographic systems, that is a testament to the rather complicated development of dislocation transformations in the structure of steel, which provide an increase of endurance at a fatigue. The increase of the limited endurance became as a result of impulsive

  11. Spasticity reduction using electrical stimulation in the lower limb of spinal cord injury patients

    NARCIS (Netherlands)

    van der Salm, Arjan

    2005-01-01

    The goal of this thesis was to investigate the influence of electrical stimulation on spasticity of leg muscles in spinal cord injury patients and its impact on gait. Both, the carry-over effect and the instant effect of electrical stimulation during gait were investigated.

  12. [Treatment of thoracic and abdominal cavity perforation complicated by Henoch-Schonlein purpura nephritis in a patient with high-voltage electric burn].

    Science.gov (United States)

    Zhang, Wei; Xie, Wei-guo; Min, Wei-xiong; Wang, De-yun; Zhang, Jia; Wan, Shi-yong

    2013-10-01

    A 55-year-old male patient suffered from severe high-voltage electric burn with an area of 20%TBSA full-thickness injury. The injury involved the distal end of left upper limb, right trunk, and whole abdominal wall. Fracture of the 7th-10th ribs was found in the right side of chest, with perforation of abdominal cavity, and bilateral pleural effusion was found. Part of the small intestine was necrotic and exposed. At the early stage, xeno-acellular dermal matrix was grafted after debridement of abdominal wound; peritoneal lavage was performed; negative pressure drainage was performed in orificium fistula of intestine for promoting the adhesion between perforated intestine and abdominal scar. Two orificium fistulas formed after closure of abdominal granulation wound by autologous skin grafting. Eschar of chest wall and denatured ribs were retained. The risk of infection of thoracic cavity was decreased by promoting the adhesion between lung tissue and chest wall. During the treatment, the patient was diagnosed with Henoch-Schonlein purpura nephritis by renal biopsy, with the symptoms of purpura in the lower limbs, heavy proteinuria, severe hypoalbuminemia, edema, etc. After control of kidney damage by immunosuppressive treatment instead of glucocorticoid, alleviation of the levels of proteinuria and blood albumin, free latissimus dorsi myocutaneous flap was excised to repair chest wall, and free skin graft was excised to repair intestinal fistula. After all the wounds were successfully covered, the patient was treated with glucocorticoid combined with immunosuppressants for more than 1 year. The patient was followed up for 3 years, and his renal function was completely recovered with satisfactory clinical outcome.

  13. Islanding detection and over voltage mitigation using wireless sensor networks and electric vehicle charging stations.

    Science.gov (United States)

    2016-06-01

    An islanding condition occurs when a distributed generation (DG) unit continues to energize a : part of the grid while said part has been isolated from the main electrical utility. In this event, if : the power of the DG exceeds the load, a transient...

  14. Two-Stage Electric Vehicle Charging Coordination in Low Voltage Distribution Grids

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Pillai, Jayakrishnan Radhakrishna

    2014-01-01

    ). Being a sizable rated element, electric vehicles (EVs) can offer a great deal of demand flexibility in future intelligent grids. This paper first investigates and analyzes driving pattern and charging requirements of EVs. Secondly, a two-stage charging algorithm, namely local adaptive control...

  15. Impact Study of Electric Vehicle (EV) Integration on Low Voltage (LV) Grids

    DEFF Research Database (Denmark)

    Wu, Qiuwei; Cha, Seung-Tae; Nielsen, Arne Hejde

    2012-01-01

    Large scale deployment of electric vehicles (EVs) has become a very interesting option because it can both reduce the greenhouse gas (GHG) emission from the transport sector and facilitate the integration of more renewable energy resources (RES) by providing the flexibility of EV charging demands...

  16. Application of Autonomous Smart Inverter Volt-VAR Function for Voltage Reduction Energy Savings and Power Quality in Electric Distribution Systems: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Fei; Nagarajan, Adarsh; Baggu, Murali; Chakraborty, Sudipta; Nguyen, Andu; Walinga, Sarah; McCarty, Michael; Bell, Frances

    2017-05-01

    This paper evaluated the impact of smart inverter Volt-VAR function on voltage reduction energy saving and power quality in electric power distribution systems. A methodology to implement the voltage reduction optimization was developed by controlling the substation LTC and capacitor banks, and having smart inverters participate through their autonomous Volt-VAR control. In addition, a power quality scoring methodology was proposed and utilized to quantify the effect on power distribution system power quality. All of these methodologies were applied to a utility distribution system model to evaluate the voltage reduction energy saving and power quality under various PV penetrations and smart inverter densities.

  17. The principle of elaboration of the relay protection against short circuits between the closely placed phases of high voltage electrical line

    Directory of Open Access Journals (Sweden)

    Kiorsak M.

    2015-12-01

    Full Text Available The article is devoted to the elaboration of the principle of relay protection against short circuits between the closely placed phases of higher voltage electrical line with self-compensation, based on the six phase’s symmetrical components. It is shown that the unsymmetrical short circuits between the closely placed phases are characterized by appearance of zero and tertiary sequences of symmetrical components. This fact can be used to choose them for relay protection. The electrical basic circuits and formulas for calculation of the passive parameters of zero and tertiary filters of currents (voltages are done. It is presented the structural-functional basic circuit scheme for relay protection against short circuits between the closely placed phases of higher voltage electrical line with self-compensation.

  18. Electrical nerve stimulation to promote micturition in spinal cord injury patients: A review of current attempts.

    Science.gov (United States)

    Ren, Jian; Chew, Daniel J; Biers, Suzanne; Thiruchelvam, Nikesh

    2016-03-01

    In this review, we focus on the current attempts of electrical nerve stimulation for micturition in spinal cord injury (SCI) patients. A literature search was performed through PubMed using "spinal cord injury," "electrical nerve stimulation AND bladder," "sacral anterior root stimulation/stimulator" and "Brindley stimulator" from January 1975 to January 2014. Twenty studies were selected for this review. Electrical nerve stimulation is a clinical option for promoting micturition in SCI patients. Well-designed, randomized and controlled studies are essential for further investigation. © 2015 Wiley Periodicals, Inc.

  19. Micro-fabricated Rotational Actuators for Electrical Voltage Measurements Employing the Principle of Electrostatic Force

    Directory of Open Access Journals (Sweden)

    an DITTMER

    2009-10-01

    Full Text Available In this paper, we present an advanced RMS voltage sensor based on rotating parallel-plate capacitors based on the principle of electrostatic force. The actuator is built using a micromechanical thin bulk silicon batch process yielding structures with a high sensitivity mainly due to a low mechanical spring constant, realized with thin and long beams. Metal layers provide separated excitation and sensing electrodes. The actuator is anodically bonded on a matching glass substrate with a shallow rectangular cavity in which the opposite electrodes are located and which defines the working distance to be as low as 2.5 μm. To avoid stiction, bumpers with a small contact area physically prevent short circuiting under pull-in conditions and thus improve the reliability. Finally design choices and the micromechanical fabrication process are explained. Moreover, DC and RF characterization results of the devices are presented showing successful operation from below 10 Hz up to more than 1 MHz.

  20. Adaptive approach for on-board impedance parameters and voltage estimation of lithium-ion batteries in electric vehicles

    Science.gov (United States)

    Farmann, Alexander; Waag, Wladislaw; Sauer, Dirk Uwe

    2015-12-01

    Robust algorithms using reduced order equivalent circuit model (ECM) for an accurate and reliable estimation of battery states in various applications become more popular. In this study, a novel adaptive, self-learning heuristic algorithm for on-board impedance parameters and voltage estimation of lithium-ion batteries (LIBs) in electric vehicles is introduced. The presented approach is verified using LIBs with different composition of chemistries (NMC/C, NMC/LTO, LFP/C) at different aging states. An impedance-based reduced order ECM incorporating ohmic resistance and a combination of a constant phase element and a resistance (so-called ZARC-element) is employed. Existing algorithms in vehicles are much more limited in the complexity of the ECMs. The algorithm is validated using seven day real vehicle data with high temperature variation including very low temperatures (from -20 °C to +30 °C) at different Depth-of-Discharges (DoDs). Two possibilities to approximate both ZARC-elements with finite number of RC-elements on-board are shown and the results of the voltage estimation are compared. Moreover, the current dependence of the charge-transfer resistance is considered by employing Butler-Volmer equation. Achieved results indicate that both models yield almost the same grade of accuracy.

  1. Wireless Power Supply via Coupled Magnetic Resonance for on-line Monitoring Wireless Sensor of High-voltage Electrical Equipment

    DEFF Research Database (Denmark)

    Xingkui, Mao; Qisheng, Huang; Yudi, Xiao

    2016-01-01

    On-line monitoring of high-voltage electrical equipment (HV-EE) aiming to detect faults effectively has become crucial to avoid serious accidents. Moreover, highly reliable power supplies are the key component for the wireless sensors equipped in such on-line monitoring systems. Therefore......, in this paper, the wireless power supply via coupled magnetic resonance (MR-WPS) is proposed for powering the wireless sensor and the associated wireless sensor solution is also proposed. The key specifications of the MR-WPS working in switchgear cabinet with a harsh operation environment are analyzed...... and determined. Design of these key parameters of the coupled magnetic resonant unit (CMRU) in MR-WPS is provided as well as the method of optimizing the resonant windings is given. Finally, a prototype is built and tested. The experimental results are presented in order to show that sufficient and reliable...

  2. Effect of oscillating electrical field stimulation on motor function recovery and myelin regeneration after spinal cord injury in rats.

    Science.gov (United States)

    Tian, Da-Sheng; Jing, Jue-Hua; Qian, Jun; Chen, Lei; Zhu, Bin

    2016-05-01

    [Purpose] The aim of this study was to evaluate the effect of oscillating electrical field stimulation on motor function recovery and myelin regeneration in rats with spinal cord injury. [Subjects and Methods] A rat model of spinal cord injury was constructed by using the Allen weight-drop method. These rats were randomly divided into normal, spinal cord injury, and spinal cord injury + oscillating electrical field stimulation groups. The experimental group received the intervention with oscillating electrical field stimulation, and the control group received the intervention with an electrical field stimulator without oscillating electrical field stimulation. Each group was then randomly divided into seven subgroups according to observation time (1, 2, 4, 6, 8, 10, and 12 weeks). Basso-Beattie-Bresnahan score and inclined plate test score evaluation, motor evoked potential detection, and histological observation were performed. [Results] In the first 2 weeks of oscillating electrical field stimulation, the oscillating electrical field stimulation and inclined plate test scores of spinal cord injury group and spinal cord injury + oscillating electrical field stimulation group were not significantly different. In the fourth week, the scores of the spinal cord injury group were significantly lower than those of the spinal cord injury + oscillating electrical field stimulation group. The motor evoked potential incubation period in the spinal cord injury + oscillating electrical field stimulation group at the various time points was shorter than that in the spinal cord injury group. In the sixth week, the relative area of myelin in the spinal cord injury + oscillating electrical field stimulation group was evidently larger than that in the spinal cord injury group. [Conclusion] Oscillating electrical field stimulation could effectively improve spinal cord conduction function and promote motor function recovery in rats with spinal cord injury, as well as promote myelin

  3. OPTIMAL CHARGING OF ELECTRICAL VEHICLES IN THE SMART CITY FOR LOSS MINIMIZATION AND VOLTAGE IMPROVEMENT

    Directory of Open Access Journals (Sweden)

    Adrian Toni Radu

    2017-06-01

    Full Text Available The world is two-thirds of the way through a century-long cycle of rapid urbanisation, at the end of which more than 70% of people will live in cities (World Health Organization, 2014. The urban transformation has become a major contributor to economic, demographic, social and environmental change. Electric vehicles (EVs have become increasingly popular over the last few years and are considered as an important means to mitigate air pollution problems in big cities around the world. With their onboard batteries, EVs also present an opportunity to serve as a demand response tool in supporting future smart grid where there is usually high penetration level of renewable energy (RE sources. In this paper, we consider the coordinated charging control of electrical vehicles in the charging stations. The goals are to illustrate how the integration of EVs at the urban area improve the overall load schedule of the distribution network.

  4. APPLICATION OF TECHNIQUE OF MAXIMUM PERMISSIBLE LEVELS OF CONTACT VOLTAGE AND CURRENTS FOR ELECTRIC SAFETY

    Directory of Open Access Journals (Sweden)

    E. A. Bondarenko

    2013-07-01

    Full Text Available In article the problem of an electro traumatism and the new approach for its decision is considered. It is noticed that the typical reasons of electro traumas are events-preconditions: an error of the person, refusal of an electric equipment and adverse external action on them; occurrence of the dangerous factor (electric energy in an unexpected place; absence or malfunction of the protection frames provided on these cases and inexact actions of the person in such situation; distribution and action of electric energy on the person. Therefore for maintenance of the accepted level of safe conditions of the person interaction with electro installations in the certain environment the new concept of electro traumatism risk reduction is offered. It is noticed that for maintenance of the accepted level of safe conditions of person interaction with electro installations in the certain environment the sudden, unapproved exit of electric energy from electro technical systems on the person should not exceed its limiting values; maximum permissible values of electric energy absorbed by a body of the person should be established taking into consideration parameters of the concrete person, limiting values of touch pressure, a current which proceeds through a body of the person, sorts, frequencies, and time of action of a current. The technique of definition of maximum permissible sizes of pressure of a touch and currents taking into account energy absorbed by the body of the person is offered. It is proved that admissible value for energy of an alternating current of industrial frequency which can be absorbed by body of the person, should not exceed value of 0,36 J. Dependence between size of a maximum permissible current of industrial frequency and times of its action, size of pressure of a touch, admissible energy which is absorbed by a body of the person, and parameters of a body of the person is received. The example of practical realization of a design

  5. Role of electrical stimulation for rehabilitation and regeneration after spinal cord injury: an overview.

    Science.gov (United States)

    Hamid, Samar; Hayek, Ray

    2008-09-01

    Structural discontinuity in the spinal cord after injury results in a disruption in the impulse conduction resulting in loss of various bodily functions depending upon the level of injury. This article presents a summary of the scientific research employing electrical stimulation as a means for anatomical or functional recovery for patients suffering from spinal cord injury. Electrical stimulation in the form of functional electrical stimulation (FES) can help facilitate and improve upper/lower limb mobility along with other body functions lost due to injury e.g. respiratory, sexual, bladder or bowel functions by applying a controlled electrical stimulus to generate contractions and functional movement in the paralysed muscles. The available rehabilitative techniques based on FES technology and various Food and Drug Administration, USA approved neuroprosthetic devices that are in use are discussed. The second part of the article summarises the experimental work done in the past 2 decades to study the effects of weakly applied direct current fields in promoting regeneration of neurites towards the cathode and the new emerging technique of oscillating field stimulation which has shown to promote bidirectional regeneration in the injured nerve fibres. The present article is not intended to be an exhaustive review but rather a summary aiming to highlight these two applications of electrical stimulation and the degree of anatomical/functional recovery associated with these in the field of spinal cord injury research.

  6. Integrating Multi-Domain Distributed Energy Systems with Electric Vehicle PQ Flexibility: Optimal Design and Operation Scheduling for Sustainable Low-Voltage Distribution Grids

    DEFF Research Database (Denmark)

    Morvaj, Boran; Knezovic, Katarina; Evins, Ralph

    2016-01-01

    Electricity and transport sectors have to be decarbonised in order to mitigate climate change effects leading to increased penetration of distributed energy systems (DES) and electric vehicles (EV) which can threaten the security of distribution grid operation. Proper design and operation...... in the stable operation. The model was applied to a real low-voltage Danish distribution grid where measurement data is available on hourly basis in order to determine EV flexibility impacts on carbon emissions, as well as the benefits of optimal DES design. The influence of EV reactive power control...... for minimising carbon emission in low-voltage distribution grids with high share of distributed energy resources and electric vehicles. The framework determines optimal EV flexibility usage (both active and reactive) while satisfying electric and thermal building demands, and maintaining the distribution grid...

  7. Frequency-dependent reduction of voltage-gated sodium current modulates retinal ganglion cell response rate to electrical stimulation

    Science.gov (United States)

    Tsai, David; Morley, John W.; Suaning, Gregg J.; Lovell, Nigel H.

    2011-10-01

    The ability to elicit visual percepts through electrical stimulation of the retina has prompted numerous investigations examining the feasibility of restoring sight to the blind with retinal implants. The therapeutic efficacy of these devices will be strongly influenced by their ability to elicit neural responses that approximate those of normal vision. Retinal ganglion cells (RGCs) can fire spikes at frequencies greater than 200 Hz when driven by light. However, several studies using isolated retinas have found a decline in RGC spiking response rate when these cells were stimulated at greater than 50 Hz. It is possible that the mechanism responsible for this decline also contributes to the frequency-dependent 'fading' of electrically evoked percepts recently reported in human patients. Using whole-cell patch clamp recordings of rabbit RGCs, we investigated the causes for the spiking response depression during direct subretinal stimulation of these cells at 50-200 Hz. The response depression was not caused by inhibition arising from the retinal network but, instead, by a stimulus-frequency-dependent decline of RGC voltage-gated sodium current. Under identical experimental conditions, however, RGCs were able to spike at high frequency when driven by light stimuli and intracellular depolarization. Based on these observations, we demonstrated a technique to prevent the spiking response depression.

  8. Power Sharing and Voltage Vector Distribution Model of a Dual Inverter Open-End Winding Motor Drive System for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Yi-Fan Jia

    2018-02-01

    Full Text Available A drive system with an open-end winding permanent magnet synchronous motor (OW-PMSM fed by a dual inverter and powered by two independent power sources is suitable for electric vehicles. By using an energy conversion device as primary power source and an energy storage element as secondary power source, this configuration can not only lower the DC-bus voltage and extend the driving range, but also handle the power sharing between two power sources without a DC/DC (direct current to direct current converter. Based on a drive system model with voltage vector distribution, this paper proposes a desired power sharing calculation method and three different voltage vector distribution methods. By their selection strategy the optimal voltage vector distribution method can be selected according to the operating conditions. On the basis of the integral synthesizing of the desired voltage vector, the proposed voltage vector distribution method can reduce the inverter switching frequency while making the primary power source follow its desired output power. Simulation results confirm the validity of the proposed methods, which improve the primary power source’s energy efficiency by regulating its output power and lessen inverter switching loss by reducing the switching frequency. This system also provides an approach to the energy management function of electric vehicles.

  9. High voltage AC plasma torches with long electric arcs for plasma-chemical applications

    Science.gov (United States)

    Surov, A. V.; Popov, S. D.; Serba, E. O.; Pavlov, A. V.; Nakonechny, Gh V.; Spodobin, V. A.; Nikonov, A. V.; Subbotin, D. I.; Borovskoy, A. M.

    2017-04-01

    Powerful AC plasma torches are in demand for a number of advanced plasma chemical applications, they can provide high enthalpy of the working gas. IEE RAS specialists have developed a number of models of stationary thermal plasma torches for continuous operation on air with the power from 5 to 500 kW, and on mixture of H2O, CO2 and CH4 up to 150 kW. AC plasma torches were tested on the pilot plasmachemical installations. Powerful AC plasma torch with hollow electrodes and the gas vortex stabilization of arc in cylindrical channels and its operation characteristics are presented. Lifetime of its continuous operation on air is 2000 hours and thermal efficiency is about 92%, the electric arc length between two electrodes of the plasma torch exceeds 2 m.

  10. Effects of intermittent 60-Hz high voltage electric fields on metabolism, activity, and temperature in mice

    Energy Technology Data Exchange (ETDEWEB)

    Rosenbergy, R.S; Duffy, P.H.; Sacher, G.A.

    1981-01-01

    Transient effects of 100-kV/m extremely low frequency electric fields were studied in the white footed deermouse, Peromyscus leucopus. Gross motor activity, carbon dioxide production, oxygen consumption, and core body temperature were monitored before, during, and after intermittent field exposures (four hour-long exposures, at one-hour intervals). Thirty-four mice were exposed in cages with plastic floors floating above ground potential, and 21 mice were exposed in cages with grounded metal floor plates. The first field exposure produced an immediate, transient increase of activity and gas measures during the inactive phase of the circadian cycle. All measures returned to baseline levels before the second exposure and were not significantly changed throughout the remainder of the exposures. The rapid habituation of field-induced arousal suggests that significant metabolic changes will not be measured in experiments in which the interval between exposure and measurement is greater than two hours.

  11. Evaluation of the effectiveness of neurofeedback in the reduction of Posttraumatic stress disorder (PTSD in a patient following high-voltage electric shock with the use of ERPs

    Directory of Open Access Journals (Sweden)

    Anna Chrapusta

    2015-09-01

    Chronic PTSD developed within the patient as a result of a high-voltage electric burn. The application of a method of therapy (neurofeedback resulted in the withdrawal of the syndrome symptoms. ERPs in a GO/NOGO task can be used to plan neurofeedback and in the assessment of functional brain changes induced by neurotherapeutic programmes. Funds Collection: Private sources.

  12. Technological Aspects: High Voltage

    CERN Document Server

    Faircloth, D.C.

    2013-12-16

    This paper covers the theory and technological aspects of high-voltage design for ion sources. Electric field strengths are critical to understanding high-voltage breakdown. The equations governing electric fields and the techniques to solve them are discussed. The fundamental physics of high-voltage breakdown and electrical discharges are outlined. Different types of electrical discharges are catalogued and their behaviour in environments ranging from air to vacuum are detailed. The importance of surfaces is discussed. The principles of designing electrodes and insulators are introduced. The use of high-voltage platforms and their relation to system design are discussed. The use of commercially available high-voltage technology such as connectors, feedthroughs and cables are considered. Different power supply technologies and their procurement are briefly outlined. High-voltage safety, electric shocks and system design rules are covered.

  13. Nanosecond pulsed electric fields (nsPEFs) low cost generator design using power MOSFET and Cockcroft-Walton multiplier circuit as high voltage DC source

    Science.gov (United States)

    Sulaeman, M. Y.; Widita, R.

    2014-09-01

    Purpose: Non-ionizing radiation therapy for cancer using pulsed electric field with high intensity field has become an interesting field new research topic. A new method using nanosecond pulsed electric fields (nsPEFs) offers a novel means to treat cancer. Not like the conventional electroporation, nsPEFs able to create nanopores in all membranes of the cell, including membrane in cell organelles, like mitochondria and nucleus. NsPEFs will promote cell death in several cell types, including cancer cell by apoptosis mechanism. NsPEFs will use pulse with intensity of electric field higher than conventional electroporation, between 20-100 kV/cm and with shorter duration of pulse than conventional electroporation. NsPEFs requires a generator to produce high voltage pulse and to achieve high intensity electric field with proper pulse width. However, manufacturing cost for creating generator that generates a high voltage with short duration for nsPEFs purposes is highly expensive. Hence, the aim of this research is to obtain the low cost generator design that is able to produce a high voltage pulse with nanosecond width and will be used for nsPEFs purposes. Method: Cockcroft-Walton multiplier circuit will boost the input of 220 volt AC into high voltage DC around 1500 volt and it will be combined by a series of power MOSFET as a fast switch to obtain a high voltage with nanosecond pulse width. The motivation using Cockcroft-Walton multiplier is to acquire a low-cost high voltage DC generator; it will use capacitors and diodes arranged like a step. Power MOSFET connected in series is used as voltage divider to share the high voltage in order not to damage them. Results: This design is expected to acquire a low-cost generator that can achieve the high voltage pulse in amount of -1.5 kV with falltime 3 ns and risetime 15 ns into a 50Ω load that will be used for nsPEFs purposes. Further detailed on the circuit design will be explained at presentation.

  14. The effect of electrical passive cycling on spasticity in war veterans with SCI (Spinal Cord Injury)

    OpenAIRE

    Rayegani, Seyed M; Hadi eShojaee; Leyla eSedighipour; Mohammad Reza eSoroush; Mohmmad eBaghbani; Omm’Ol Banin eAmirani

    2011-01-01

    Introduction: Muscle atrophy, spasticity and deformity are among long term complication of Spinal Cord Injury(SCI) veterans. There are numerous studies evaluating effect of functional electrical stimulation (FES) on muscle properties of SCI people, but less research has focused on the benefits of passive cycling in the management of spasm and improving ROM of lower limbs in individuals with SCI. Aims: To evaluate the effect of electrical passive cycling on passive range of movement spasticit...

  15. The Effect of Electrical Passive Cycling on Spasticity in War Veterans with Spinal Cord Injury

    OpenAIRE

    Rayegani, Seyed Mansoor; Shojaee, Hadi; Sedighipour, Leyla; Soroush, Mohammad Reza; Baghbani, Mohammad; Amirani, Omm’ol Banin

    2011-01-01

    Introduction: Muscle atrophy, spasticity, and deformity are among long term complication of spinal cord injury (SCI) veterans. There are numerous studies evaluating effect of functional electrical stimulation on muscle properties of SCI people, but less research has focused on the benefits of passive cycling in the management of spasticity and improving ROM of lower limbs in individuals with SCI. Aims: To evaluate the effect of electrical passive cycling on passive range of movement spasticit...

  16. The effect of the variable frequency drive of the CNC roll grinding machine on the operation of other devices in low-voltage electrical installation

    Directory of Open Access Journals (Sweden)

    Simić Ninoslav

    2016-01-01

    Full Text Available This paper presents one of the observations that have been collected during the years of testing of electrical installations. A typical case from industrial plant in which are installed loads with variable frequency regulation is analyzed. We propose a simple way by measuring the frequency of the voltage in the objects, to establish the existence of possible irregularities in the operation of the individual units and analyze the influence of the current and voltage signal shape of one load to the work of other loads in the plant. The need for verification of electrical installations immediately upon receipt and installation of electrical equipment is emphasized and the use of the latest standards in the design and selection of equipment, in order to avoid unplanned expenses is recommended.

  17. High resolution separations of charge variants and disulfide isomers of monoclonal antibodies and antibody drug conjugates using ultra-high voltage capillary electrophoresis with high electric field strength.

    Science.gov (United States)

    Henley, W Hampton; He, Yan; Mellors, J Scott; Batz, Nicholas G; Ramsey, J Michael; Jorgenson, James W

    2017-11-10

    Ultra-high voltage capillary electrophoresis with high electric field strength has been applied to the separation of the charge variants, drug conjugates, and disulfide isomers of monoclonal antibodies. Samples composed of many closely related species are difficult to resolve and quantify using traditional analytical instrumentation. High performance instrumentation can often save considerable time and effort otherwise spent on extensive method development. Ideally, the resolution obtained for a given CE buffer system scales with the square root of the applied voltage. Currently available commercial CE instrumentation is limited to an applied voltage of approximately 30kV and a maximum electric field strength of 1kV/cm due to design limitations. The instrumentation described here is capable of safely applying potentials of at least 120kV with electric field strengths over 2000V/cm, potentially doubling the resolution of the best conventional CE buffer/capillary systems while decreasing analysis time in some applications. Separations of these complex mixtures using this new instrumentation demonstrate the potential of ultra-high voltage CE to identify the presence of previously unresolved components and to reduce analysis time for complex mixtures of antibody variants and drug conjugates. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Assessment of Environmental Qualification Practices and Condition Monitoring Techniques for Low-Voltage Electric Cables: LOCA Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Lofaro, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Grove, E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Villaran, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Soo, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hsu, F. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2001-02-01

    This report documents the results of a research program addressing issues related to the qualification process for low-voltage instrumentation and control (I&C) electric cables used in commercial nuclear power plants. Three commonly used types of I&C cable were tested: Cross-Linked Polyethylene (XLPE) insulation with a Neoprene® jacket, Ethylene Propylene Rubber (EPR) insulation with an unbonded Hypalon® jacket, and EPR with a bonded Hypalon® jacket. Each cable type received accelerated aging to simulate 20, 40, and 60 years of qualified life. In addition, naturally aged cables of the same types were obtained from decommissioned nuclear power plants and tested. The cables were subjected to simulated loss-of-coolant-accident (LOCA) conditions, which included the sequential application of LOCA radiation followed by exposure to steam at high temperature and pressure, as well as to chemical spray. Periodic condition monitoring (CM) was performed using nine different techniques to obtain data on the condition of the cable, as well as to evaluate the effectiveness of those CM techniques for in situ monitoring of cables. Volume 1 of this report presents the results of the LOCA tests, and Volume 2 discusses the results of the condition monitoring tests.

  19. Hard- and software of real time simulation tools of Electric Power System for adequate modeling power semiconductors in voltage source convertor based HVDC and FACTS

    Directory of Open Access Journals (Sweden)

    Ufa Ruslan A.

    2014-01-01

    Full Text Available The motivation of the presented research is based on the needs for development of new methods and tools for adequate simulation of Flexible Alternating Current Transmission System (FACTS devices and High Voltage Direct Current Transmission (HVDC system as part of real electric power systems (EPS. For that, a hybrid approach for advanced simulation of the FACTS and HVDC based on Voltage Source is proposed. The presented simulation results of the developed hybrid model of VSC confirm the achievement of the desired properties of the model and the effectiveness of the proposed solutions.

  20. Fatal and non-fatal burn injuries with electrical weapons and explosive fumes.

    Science.gov (United States)

    Kroll, Mark W; Ritter, Mollie B; Williams, Howard E

    2017-08-01

    While generally reducing morbidity and mortality, electrical weapons have risks associated with their usage, including eye injuries and falls. With the presence of explosive fumes or fuels there also exists the possibility of burn injury. We searched for cases of fatal and non-fatal major burns with TASER® electrical weapon usage where there was a possibility that the weapon ignited the explosion. We confirmed 6 cases of fatal burn injury and 4 cases of major non-fatal burns out of 3.17 million field uses. The mean age was 35.5 ± 9.7 years which is consistent with the typical arrest-related death. Moderate, minor, and noninjurious fires - typically due to a cigarette lighters in a pocket, petrol, recreational inhalants, or body spray were also noted. The use of electrical weapons presents a small but real risk of death from fatal burn injury. It also presents a small risk of major non-fatal burn injury. The ignition of petrol fumes dominates these cases of major fatal and nonfatal burns. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  1. pattern of severe electrical injuries in a nigerian regional burn centre

    African Journals Online (AJOL)

    Methods: A 10-year retrospective study of case files of patients seen with electrical injuries in our centre was carried out from January 1995 to December 2004. Case notes were retrieved and data collated from them were analysed by descriptive statistics. Results: Twenty four (24) case files met the inclusion criteria and ...

  2. Atlantic Cod Show a Highly Variable Sensitivity to Electric-Induced Spinal Injuries

    NARCIS (Netherlands)

    Soetaert, M.; Haan, de D.; Verschueren, B.; Decostere, A.; Puvanendran, V.; Saunders, J.; Polet, H.; Chiers, K.

    2016-01-01

    Pulse trawling is the most promising alternative to conventional beam trawls targeting Sole Solea solea (also known as Solea vulgaris), but due to the electric fields created by electrotrawls spinal injuries are reported in gadoid round fishes such as Atlantic Cod Gadus morhua. This study aimed

  3. Fatal cranial injuries caused by an electric angle grinder.

    Science.gov (United States)

    Telmon, N; Allery, J P; Scolan, V; Rougé, D

    2001-03-01

    A case of fatal cranial injuries caused by an angle grinder is reported. The scalp lesions were typical of those produced by a cutting disk in a side-slipping movement. On the cranial vault were two bony losses of substance, one of which was deep enough for intracranial penetration of the disk. Signs of deflection of the disk, identical to those found on the scalp, were observed on the external bony table. Because of the circumstances in which the victim was discovered, in particular the damage to the machine which had a broken handle, and the lack of any indication of homicide or suicide, an accident is the most likely hypothesis.

  4. Mechanical ventilation guided by electrical impedance tomography in experimental acute lung injury.

    Science.gov (United States)

    Wolf, Gerhard K; Gómez-Laberge, Camille; Rettig, Jordan S; Vargas, Sara O; Smallwood, Craig D; Prabhu, Sanjay P; Vitali, Sally H; Zurakowski, David; Arnold, John H

    2013-05-01

    To utilize real-time electrical impedance tomography to guide lung protective ventilation in an animal model of acute respiratory distress syndrome. Prospective animal study. Animal research center. Twelve Yorkshire swine (15 kg). Lung injury was induced with saline lavage and augmented using large tidal volumes. The control group (n = 6) was ventilated using ARDSnet guidelines, and the electrical impedance tomography-guided group (n = 6) was ventilated using guidance with real-time electrical impedance tomography lung imaging. Regional electrical impedance tomography-derived compliance was used to maximize the recruitment of dependent lung and minimize overdistension of nondependent lung areas. Tidal volume was 6 mL/kg in both groups. Computed tomography was performed in a subset of animals to define the anatomic correlates of electrical impedance tomography imaging (n = 5). Interleukin-8 was quantified in serum and bronchoalveolar lavage samples. Sections of dependent and nondependent regions of the lung were fixed in formalin for histopathologic analysis. Positive end-expiratory pressure levels were higher in the electrical impedance tomography-guided group (14.3 cm H₂O vs. 8.6 cm H₂O; p electrical impedance tomography-guided group (6.9 mL/cm H₂O vs. 4.7 mL/cm H₂O; p = 0.013). Regional electrical impedance tomography-derived compliance of the most dependent lung region was increased in the electrical impedance tomography group (1.78 mL/cm H₂O vs. 0.99 mL/cm H₂O; p = 0.001). Pao₂/FIO₂ ratio was higher and oxygenation index was lower in the electrical impedance tomography-guided group (Pao₂/FIO₂: 388 mm Hg vs. 113 mm Hg, p electrical impedance tomography-guided group (HMEIT 42% samples vs. HMCONTROL 67% samples, p electrical impedance tomography and computed tomography were ± 16%. Electrical impedance tomography-guided ventilation resulted in improved respiratory mechanics, improved gas exchange, and reduced histologic evidence of ventilator

  5. Strongly correlated material under voltage: The electrical breakdown in V{sub 2}O{sub 3} at the insulator to metal transition

    Energy Technology Data Exchange (ETDEWEB)

    Guenon, Stefan; Wang, Siming; Ramirez, Juan Gabriel; Schuller, Ivan K. [Department of Physics and Center for Advanced Nanoscience, University of California, San Diego (United States); Scharinger, Sebastian; Koelle, Dieter; Kleiner, Reinhold [Physikalisches Institut and Center for Collective Quantum Phenomena and their Applications in LISAplus, Universitaet Tuebingen (Germany)

    2013-07-01

    We have investigated the electrical properties of a V{sub 2}O{sub 3} thin film micro bridge. Discontinuous jumps to lower voltages in the current voltage characteristic (IV) followed by an approximately constant voltage progression for high currents indicate an electrical breakdown of the device. In addition, the IV curves show hysteresis and a training effect, i.e. the subsequent IV loops are different from the first IV loop after thermal cycling. Low temperature scanning electron microscopy (LTSEM) reveals that the electrical breakdown over the whole device is caused by the formation of electro-thermal domains (ETDs), i.e. the current and temperature redistribution. On the contrary, at the nanoscale, the electrical breakdown causes the insulator to metal transition of individual domains. In a numerical model we considered these domains as a network of resistors and we were able to reproduce the electro-thermal breakdown as well as the hysteresis and the training effect in the IVs.

  6. The Effect of the Nonlinearity of the Response of Lipid Membranes to Voltage Perturbations on the Interpretation of Their Electrical Properties. A New Theoretical Description

    Directory of Open Access Journals (Sweden)

    Lars D. Mosgaard

    2015-09-01

    Full Text Available Our understanding of the electrical properties of cell membranes is derived from experiments where the membrane is exposed to a perturbation (in the form of a time-dependent voltage or current change and information is extracted from the measured output. The interpretation of such electrical recordings consists in finding an electronic equivalent that would show the same or similar response as the biological system. In general, however, there is no unique circuit configuration, which can explain a single electrical recording and the choice of an electric model for a biological system is based on complementary information (most commonly structural information of the system investigated. Most of the electrophysiological data on cell membranes address the functional role of protein channels while assuming that the lipid matrix is an insulator with constant capacitance. However, close to their melting transition the lipid bilayers are no inert insulators. Their conductivity and their capacitance are nonlinear functions of both voltage, area and volume density. This has to be considered when interpreting electrical data. Here we show how electric data commonly interpreted as gating currents of proteins and inductance can be explained by the nonlinear dynamics of the lipid matrix itself.

  7. Functional electrical stimulation for the upper limb in tetraplegic spinal cord injury: a systematic review.

    Science.gov (United States)

    Patil, Siddeshwar; Raza, Wajid A; Jamil, Firas; Caley, Richard; O'Connor, Rory J

    2014-01-01

    Technological advances have helped to improve functional ability in spinal cord injury survivors. The aim of this study is to systematically review the evidence for functional electrical stimulation (FES) on functional tasks involving the upper limb in people with spinal cord injuries. The authors systematically searched from September 2009 to September 2014 in relevant databases using a combination of keywords covering spinal cord injury and FES. Studies were selected using pre-determined criteria. The search yielded 144 studies. Only five studies met the inclusion criteria. All five reported improvements immediately and at follow-up in functional ability as a result of FES or FES combined with conventional therapy. There is some preliminary evidence that FES may reduce disability due to upper limb-related activity limitations in tetraplegic spinal cord injury. Further work needs to examine the role of FES in more detail and in combination with other treatments.

  8. Clinical management of electrical burns in the developing world: a case of electrical burn injury left untreated leading to amputation.

    Science.gov (United States)

    Choong, Marcus; Chy, Delia; Guevarra, Jerric R; Ross, Allen G

    2017-02-15

    We discuss the case of a 26-year-old male patient from Northern Samar, the Philippines who was left without essential health services after the amputation of all four limbs following a high voltage (20 000 volts) injury in Metro Manila in 2011. Local health services in the developing world are faced with enormous challenges in providing first-line care for burn patients. The cost of maintaining a burn unit, finding suitable qualified staff, and appropriate referral mechanisms are only some of the challenges faced. Once a patient is discharged from hospital they face more obstacles in obtaining artificial limbs, physiotherapy and access to mental health services. Disability pensions are non-existent thus patients place a considerable lifelong burden on their families. 2017 BMJ Publishing Group Ltd.

  9. Electrical impedance myography for discriminating traumatic peripheral nerve injury in the upper extremity.

    Science.gov (United States)

    Li, Zhao; Tian, Dong; Chen, Lingfen; Wang, Xiaoqing; Jiang, Lijuan; Yu, Yude

    2017-02-01

    To evaluate the potential of electrical impedance myography (EIM), which is sensitive to the changes in muscle structure and physiology, in discriminating traumatic peripheral nerve injury (TPNI) in the upper extremity. To identify factors that primarily influence muscle atrophy secondary to nerve injury. Thirty-nine patients with TPNI underwent EIM measurement and standard electromyography tests for multiple muscles in the upper extremity. The side-to-side differences in EIM parameters were calculated for each subject and compared with the compound motor action potential (CMAP) amplitude, which is a measure of injury severity, and the time since injury. The reactance and phase values of the affected muscles were consistently lower than those of healthy muscles, with an average side-to-side difference of approximately -50% (pinjury, had a greater effect on the side-to-side difference of phase values. EIM discriminates TPNI by revealing asymmetries in reactance and phase values. The severity of injury had a larger influence than the time since injury on muscle atrophy secondary to nerve injury. These results demonstrate the putative use of EIM in discriminating TPNI and deserves further study. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  10. Nanosecond pulsed electric fields depolarize transmembrane potential via voltage-gated K+, Ca2+and TRPM8 channels in U87 glioblastoma cells.

    Science.gov (United States)

    Burke, Ryan C; Bardet, Sylvia M; Carr, Lynn; Romanenko, Sergii; Arnaud-Cormos, Delia; Leveque, Philippe; O'Connor, Rodney P

    2017-10-01

    Nanosecond pulsed electric fields (nsPEFs) have a variety of applications in the biomedical and biotechnology industries. Cancer treatment has been at the forefront of investigations thus far as nsPEFs permeabilize cellular and intracellular membranes leading to apoptosis and necrosis. nsPEFs may also influence ion channel gating and have the potential to modulate cell physiology without poration of the membrane. This phenomenon was explored using live cell imaging and a sensitive fluorescent probe of transmembrane voltage in the human glioblastoma cell line, U87 MG, known to express a number of voltage-gated ion channels. The specific ion channels involved in the nsPEF response were screened using a membrane potential imaging approach and a combination of pharmacological antagonists and ion substitutions. It was found that a single 10ns pulsed electric field of 34kV/cm depolarizes the transmembrane potential of cells by acting on specific voltage-sensitive ion channels; namely the voltage and Ca2 + gated BK potassium channel, L- and T-type calcium channels, and the TRPM8 transient receptor potential channel. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Computation of Pacemakers Immunity to 50 Hz Electric Field: Induced Voltages 10 Times Greater in Unipolar Than in Bipolar Detection Mode

    Directory of Open Access Journals (Sweden)

    Cihan Gercek

    2017-03-01

    Full Text Available Thisstudy aims to compute 50 Hz electric field interferences on pacemakers for diverse lead configurations and implantation positions. Induced phenomena in a surface-based virtual human model (standing male grounded with arms closed, 2 mm resolution are computed for vertical exposure using CST EM® 3D software, with and without an implanted pacemaker. Induced interference voltages occurring on the pacemaker during exposure are computed and the results are discussed. The bipolar mode covers 99% of the implanted pacing leads in the USA and Europe, according to statistics. The tip-to-ring distance of a lead may influence up to 46% of the induced voltage. In bipolar sensing mode, right ventricle implantation has a 41% higher induced voltage than right atrium implantation. The induced voltage is in average 10 times greater in unipolar mode than in bipolar mode, when implanted in the right atrium or right ventricle. The electric field threshold of interference for a bipolar sensing mode in the worst case setting is 7.24 kV·m−1, and 10 times higher for nominal settings. These calculations will be completed by an in vitro study.

  12. Performance analysis of the PLC (Power Line Communication) in medium voltage electrical networks; Analise de desempenho de sistemas PLC em redes eletricas de media tensao

    Energy Technology Data Exchange (ETDEWEB)

    Mota, A.A.; Paleta, R. [Pontificia Universidade Catolica de Campinas (PUC-Campinas), SP (Brazil)], E-mail: amota@puc-campinas.edu.br; Mota, L.T.M.; Ricardo, R.A. [Indelmatec Engenharia, Campinas, SP (Brazil)], E-mail: mota@indelmatec.com.br

    2009-07-01

    Nowadays, the information access in communication networks is widely explored due to the increase of Internet users. In this context, the PLC (Power Line Communication) technology is an alternative for data transmission. This technology is based on the usage of transmission/distribution power lines for data transmission. However there are some problems related to the usage of this technology: adequate data transmission rates and generation of acceptable levels of electromagnetic interference (EMI). This work had the objective of studying the performance of PLC systems in medium voltage electrical networks, through the assess of data transmission rates and the generated EMI. Tests were carried out in a test field that corresponded to a medium voltage electrical network and the obtained results show that, under some circumstances, the PLC system does not reach the existent technical recommendations. (author)

  13. Influence of a Weak Field of Pulsed DC Electricity on the Behavior and Incidence of Injury in Adult Steelhead and Pacific Lamprey, Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Mesa, Matthew

    2009-02-13

    electrofishing operations typically use high voltage and amperage settings and a variety of waveforms, pulse widths (PW), and pulse frequencies (PF), depending on conditions and target species. For example, when backpack electrofishing for trout in a small stream, one might use settings such as 500 V pulsed DC, a PW of 1 ms, and a PF of 60 Hz. In contrast, the electrical barrier proposed by SRI will produce electrical conditions significantly lower than those used in electrofishing, particularly for PW and PF (e.g., PW ranging from 300-1,000 {micro}s and PF from 2-3 Hz). Further, voltage gradients (in V/cm) are predicted to be lower in the electric barrier than those produced during typical electrofishing. Although the relatively weak, pulsed DC electric fields to be produced by the barrier may be effective at deterring pinnipeds, little, if anything, is known about the effects of such low intensity electrical fields on fish behavior. For this research, we evaluated the effects of weak, pulsed DC electric currents on the behavior of adult steelhead and Pacific lamprey and the incidence of injury in steelhead only. In a series of laboratory experiments, we: (1) documented the rate of passage of fish over miniature, prototype electric barriers when they were on and off; (2) determined some electric thresholds beyond which fish would not pass over the barrier; and (3) assessed the incidence and severity of injury in steelhead exposed to relatively severe electrical conditions. The results of this study should be useful for making decisions about whether to install electrical barriers in the lower Columbia River, or elsewhere, to reduce predation on upstream migrating salmonids and other fishes by marine pinnipeds.

  14. Image registration algorithm for high-voltage electric power live line working robot based on binocular vision

    Science.gov (United States)

    Li, Chengqi; Ren, Zhigang; Yang, Bo; An, Qinghao; Yu, Xiangru; Li, Jinping

    2017-12-01

    In the process of dismounting and assembling the drop switch for the high-voltage electric power live line working (EPL2W) robot, one of the key problems is the precision of positioning for manipulators, gripper and the bolts used to fix drop switch. To solve it, we study the binocular vision system theory of the robot and the characteristic of dismounting and assembling drop switch. We propose a coarse-to-fine image registration algorithm based on image correlation, which can improve the positioning precision of manipulators and bolt significantly. The algorithm performs the following three steps: firstly, the target points are marked respectively in the right and left visions, and then the system judges whether the target point in right vision can satisfy the lowest registration accuracy by using the similarity of target points' backgrounds in right and left visions, this is a typical coarse-to-fine strategy; secondly, the system calculates the epipolar line, and then the regional sequence existing matching points is generated according to neighborhood of epipolar line, the optimal matching image is confirmed by calculating the similarity between template image in left vision and the region in regional sequence according to correlation matching; finally, the precise coordinates of target points in right and left visions are calculated according to the optimal matching image. The experiment results indicate that the positioning accuracy of image coordinate is within 2 pixels, the positioning accuracy in the world coordinate system is within 3 mm, the positioning accuracy of binocular vision satisfies the requirement dismounting and assembling the drop switch.

  15. Solution processed self-assembled monolayer gate dielectrics for low-voltage organic transistors. : Section Title: Electric Phenomena

    NARCIS (Netherlands)

    Ball, James; Wobkenberg, Paul H.; Colleaux, Florian; Kooistra, Floris B.; Hummelen, Jan C.; Bradley, Donal D. C.; Anthopoulos, Thomas D.

    2008-01-01

    Low-voltage org. transistors are sought for implementation in high vol. low-power portable electronics of the future. Here we assess the suitability of three phosphonic acid based self-assembling mols. for use as ultra-thin gate dielecs. in low-voltage soln. processable org. field-effect

  16. Module Nine: Relationships of Current, Counter EMF, and Voltage in LR Circuits; Basic Electricity and Electronics Individualized Learning System.

    Science.gov (United States)

    Bureau of Naval Personnel, Washington, DC.

    The student will study the ways that inductance affects voltage and current in Direct Current (DC) and Alternating Current (AC) circuits and why and how inductors cause these actions. The module is divided into six lessons: rise and decay of current and voltage, LR (inductive-resistive) time constant, using the universal TC (time constant) chart,…

  17. Implanted electro-acupuncture electric stimulation improves outcome of stem cells' transplantation in spinal cord injury.

    Science.gov (United States)

    Liu, Haichun; Yang, Kaiyun; Xin, Tao; Wu, Wenliang; Chen, Yunzhen

    2012-10-01

    Spinal cord injury (SCI) is one of the most serious disorders in clinics, and the high disability rate and functional deficits are common issues in patients. Transplantation of bone-marrow-derived mesenchymal stromal cells (BMSCs) into the injured spinal cord is emerging as a novel method in the therapeutics of SCI; however, its application is limited by the poor survival rate of the transplanted cells and low differentiation rate into neurons. Our laboratory recently reported that electrical stimulation (ES) dramatically improves the survival rate of transplanted BMSCs and increases spinal cord functions in animals with spinal cord injury. In this paper, we asked whether implanted electro-acupuncture (iEA) can advance the beneficial effects from the ES treatment in animals with spinal cord injury. We showed that BMSCs transplantation alone resulted in significant functional recovery in animals. Interestingly, iEA with BMSCs treatment induced a significantly higher functional improvement in locomotor functions and SSEP compared to the BMSCs treatment alone. Additionally, we used molecular biology techniques and showed that BMSCs transplantation with iEA treatment significantly increased the number of surviving BMSCs compared to the BMSCs alone group. In conclusion, our experiment showed that the approach of coupling iEA electric stimulation and BMSCs transplantation remarkably promotes functional improvements in animals with spinal cord injury and holds promising potential to treat spinal cord injury in humans.

  18. [The application of ultrasonography to estimate blood vessel injury of upper limbs sustaining electric burns].

    Science.gov (United States)

    Chai, Jia-ke; Li, Li-gen; Chen, Yue-xiu; Hu, Xiao-juan; Yang, Yong-ming

    2003-12-01

    To explore a new method in estimating extent and degree of arterial injury in upper limbs sustaining high tension electric burns. Eighteen patients (twenty-four upper limbs) with high tension electricity injury were admitted from December 1998 to September 2002, The damaged limbs consisted of four parts: wrist wound part, 5 cm, 10 cm, 15 cm parts around wrist wound, where the radial and ulnar arteries were detected using B ultrasound and color WP Doppler examination. The changes of endangium, vessel diameter, thickness of the vessel wall and volume of blood flow were recorded respectively. The parameters of normal radial and ulnar arteries were also determined as normal control. B ultrasound and color WP Doppler examination showed that the endangium in radial and ulnar arteries become coarse, edema or exfoliation. The vessel wall was thicker than that of the normal control and the thickness was heterogeneity. The vessel wall could be necrosis in severe patient and the vessel cavity was stricture or beaded. Thrombosis or occlusion could occur at the site of severe injury area in vessel. The decrease in volume of blood flow was observed. The condition of the radial and ulnar arteries become well apart from 10 - 15 cm of wrist wound. The ultrasonography can be used to detect the changes in endangium, diameter, thickness of the vessel wall, blood flow volume in injury blood vessel caused by electric burn injury. It is helpful in judging the degree and extent of injury vessel and could be a safe, non-invasive diagnostic method and is worth popularizing.

  19. Electrical impedance tomography (EIT) for quantification of pulmonary edema in acute lung injury.

    Science.gov (United States)

    Trepte, Constantin J C; Phillips, Charles R; Solà, Josep; Adler, Andy; Haas, Sebastian A; Rapin, Michael; Böhm, Stephan H; Reuter, Daniel A

    2016-01-22

    Assessment of pulmonary edema is a key factor in monitoring and guidance of therapy in critically ill patients. To date, methods available at the bedside for estimating the physiologic correlate of pulmonary edema, extravascular lung water, often are unreliable or require invasive measurements. The aim of the present study was to develop a novel approach to reliably assess extravascular lung water by making use of the functional imaging capabilities of electrical impedance tomography. Thirty domestic pigs were anesthetized and randomized to three different groups. Group 1 was a sham group with no lung injury. Group 2 had acute lung injury induced by saline lavage. Group 3 had vascular lung injury induced by intravenous injection of oleic acid. A novel, noninvasive technique using changes in thoracic electrical impedance with lateral body rotation was used to measure a new metric, the lung water ratioEIT, which reflects total extravascular lung water. The lung water ratioEIT was compared with postmortem gravimetric lung water analysis and transcardiopulmonary thermodilution measurements. A significant correlation was found between extravascular lung water as measured by postmortem gravimetric analysis and electrical impedance tomography (r = 0.80; p electrical impedance tomograms during lateral body rotation. The novel lung water ratioEIT holds promise to become a noninvasive bedside measure of pulmonary edema.

  20. Ventilation Limits Aerobic Capacity after Functional Electrical Stimulation Row Training in High Spinal Cord Injury.

    Science.gov (United States)

    Qiu, Shuang; Alzhab, Saeed; Picard, Glen; Taylor, J Andrew

    2016-06-01

    In the able-bodied, exercise training results in increased ventilatory capacity to meet increased aerobic demands of trained skeletal muscle. However, after spinal cord injury (SCI), peak ventilation can be limited by pulmonary muscle denervation. In fact, peak ventilation may restrict aerobic capacity in direct relation to injury level. Hybrid functional electrical stimulation (FES) exercise training results in increased aerobic capacity and dissociation between aerobic capacity and injury level in those with injuries at T3 and below. However, injuries above T3 have the greatest pulmonary denervation, and ventilatory capacity may restrict the increase in aerobic capacity with hybrid FES training. We assessed relationships among injury level, peak ventilation, and peak aerobic capacity and calculated oxygen uptake efficiency slope during hybrid FES exercise in 12 individuals (1 female) with SCI at level T2 to C4 (injury duration = 0.33-33 yr, age = 20-60 yr), before and after 6 months of FES-row training (FES-RT). Training increased peak aerobic capacity by 12% (P = 0.02) with only a modest increase in peak ventilation (7 of 12 subjects, P = 0.09). Both before and after training, injury level was directly related to peak ventilation (R = 0.48 and 0.43) and peak aerobic capacity (R = 0.70 and 0.55). Before training, the relationship of peak aerobic capacity to peak ventilation was strong (R = 0.62), however, after training, this relationship became almost completely linearized (R = 0.84). In addition, oxygen uptake efficiency slope increased by 11% (P injuries (above T3) appears to restrict aerobic capacity.

  1. Device for monitoring cell voltage

    Science.gov (United States)

    Doepke, Matthias [Garbsen, DE; Eisermann, Henning [Edermissen, DE

    2012-08-21

    A device for monitoring a rechargeable battery having a number of electrically connected cells includes at least one current interruption switch for interrupting current flowing through at least one associated cell and a plurality of monitoring units for detecting cell voltage. Each monitoring unit is associated with a single cell and includes a reference voltage unit for producing a defined reference threshold voltage and a voltage comparison unit for comparing the reference threshold voltage with a partial cell voltage of the associated cell. The reference voltage unit is electrically supplied from the cell voltage of the associated cell. The voltage comparison unit is coupled to the at least one current interruption switch for interrupting the current of at least the current flowing through the associated cell, with a defined minimum difference between the reference threshold voltage and the partial cell voltage.

  2. High voltage engineering

    CERN Document Server

    Rizk, Farouk AM

    2014-01-01

    Inspired by a new revival of worldwide interest in extra-high-voltage (EHV) and ultra-high-voltage (UHV) transmission, High Voltage Engineering merges the latest research with the extensive experience of the best in the field to deliver a comprehensive treatment of electrical insulation systems for the next generation of utility engineers and electric power professionals. The book offers extensive coverage of the physical basis of high-voltage engineering, from insulation stress and strength to lightning attachment and protection and beyond. Presenting information critical to the design, selec

  3. Measurement of the internal stress and electric field in a resonating piezoelectric transformer for high-voltage applications using the electro-optic and photoelastic effects.

    Science.gov (United States)

    VanGordon, James A; Kovaleski, Scott D; Norgard, Peter; Gall, Brady B; Dale, Gregory E

    2014-02-01

    The high output voltages from piezoelectric transformers are currently being used to accelerate charged particle beams for x-ray and neutron production. Traditional methods of characterizing piezoelectric transformers (PTs) using electrical probes can decrease the voltage transformation ratio of the device due to the introduction of load impedances on the order of hundreds of kiloohms to hundreds of megaohms. Consequently, an optical diagnostic was developed that used the photoelastic and electro-optic effects present in piezoelectric materials that are transparent to a given optical wavelength to determine the internal stress and electric field. The combined effects of the piezoelectric, photoelastic, and electro-optic effects result in a time-dependent change the refractive indices of the material and produce an artificially induced, time-dependent birefringence in the piezoelectric material. This induced time-dependent birefringence results in a change in the relative phase difference between the ordinary and extraordinary wave components of a helium-neon laser beam. The change in phase difference between the wave components was measured using a set of linear polarizers. The measured change in phase difference was used to calculate the stress and electric field based on the nonlinear optical properties, the piezoelectric constitutive equations, and the boundary conditions of the PT. Maximum stresses of approximately 10 MPa and electric fields of as high as 6 kV/cm were measured with the optical diagnostic. Measured results were compared to results from both a simple one-dimensional (1D) model of the piezoelectric transformer and a three-dimensional (3D) finite element model. Measured stresses and electric fields along the length of an operating length-extensional PT for two different electrical loads were within at least 50 % of 3D finite element simulated results. Additionally, the 3D finite element results were more accurate than the results from the 1D model

  4. Measurement of the internal stress and electric field in a resonating piezoelectric transformer for high-voltage applications using the electro-optic and photoelastic effects

    Science.gov (United States)

    VanGordon, James A.; Kovaleski, Scott D.; Norgard, Peter; Gall, Brady B.; Dale, Gregory E.

    2014-02-01

    The high output voltages from piezoelectric transformers are currently being used to accelerate charged particle beams for x-ray and neutron production. Traditional methods of characterizing piezoelectric transformers (PTs) using electrical probes can decrease the voltage transformation ratio of the device due to the introduction of load impedances on the order of hundreds of kiloohms to hundreds of megaohms. Consequently, an optical diagnostic was developed that used the photoelastic and electro-optic effects present in piezoelectric materials that are transparent to a given optical wavelength to determine the internal stress and electric field. The combined effects of the piezoelectric, photoelastic, and electro-optic effects result in a time-dependent change the refractive indices of the material and produce an artificially induced, time-dependent birefringence in the piezoelectric material. This induced time-dependent birefringence results in a change in the relative phase difference between the ordinary and extraordinary wave components of a helium-neon laser beam. The change in phase difference between the wave components was measured using a set of linear polarizers. The measured change in phase difference was used to calculate the stress and electric field based on the nonlinear optical properties, the piezoelectric constitutive equations, and the boundary conditions of the PT. Maximum stresses of approximately 10 MPa and electric fields of as high as 6 kV/cm were measured with the optical diagnostic. Measured results were compared to results from both a simple one-dimensional (1D) model of the piezoelectric transformer and a three-dimensional (3D) finite element model. Measured stresses and electric fields along the length of an operating length-extensional PT for two different electrical loads were within at least 50 % of 3D finite element simulated results. Additionally, the 3D finite element results were more accurate than the results from the 1D model

  5. Exercise adherence during home-based functional electrical stimulation cycling by individuals with spinal cord injury.

    Science.gov (United States)

    Dolbow, David R; Gorgey, Ashraf S; Ketchum, Jessica M; Moore, Jewel R; Hackett, Laurel A; Gater, David R

    2012-11-01

    The typically sedentary spinal cord injured population has limited physical activity options because of muscle paralysis, difficulties in transportation, and barriers to access rehabilitation/wellness facilities. It is important to investigate physical activity alternatives to increase physical activity levels and decrease the risk of inactivity-derived diseases. The goal of this study was to determine the effects of a home-based functional electrical stimulation cycling program on exercise adherence of those with spinal cord injury. Seventeen Veterans with posttraumatic C4-T11 American Spinal Injury Association Impairment Scale A-C spinal cord injury participated in two 8-wk exercise periods of home-based functional electrical stimulation lower extremity cycling. Exercise adherence and the effects of six factors thought to influence exercise adherence were studied during both exercise periods. Exercise adherence rates for exercise periods 1 and 2 were 71.7% and 62.9%, respectively. Age, history of exercise, and pain not associated with the exercise activity were determined to have significant impact on exercise adherence rates. Exercise adherence rates were well above the reported 35% in the able-bodied population, which provides evidence for the feasibility of a home-based functional electrical stimulation lower extremity cycling program. Younger adults with a history of being physically active have the highest potential for exercise adherence.

  6. High-tension electrical injury to the heart as assessed by radionuclide imaging

    Energy Technology Data Exchange (ETDEWEB)

    Iino, Hitoshi; Chikamori, Taishiro; Hatano, Tsuguhisa [Tokyo Medical Coll. (Japan)] [and others

    2002-12-01

    The purpose of this study was to evaluate cardiac complications associated with electrical injury, 7 patients with high-tension electrical injury (6,600 V alternating current) underwent {sup 201}Tl and {sup 123}I-metaiodobenzylguanidine (MIBG) imaging in addition to conventional electrocardiographic and echocardiographic assessments. Electrocardiography showed transient atrial fibrillation, second degree atrioventricular block, ST-segment depression, and sinus bradycardia in each patient. Echocardiography showed mild hypokinesis of the anterior wall in only 2 patients, but {sup 201}Tl and {sup 123}I-MIBG myocardial scintigraphy showed an abnormal scan image in 6/7 and 5/6 patients, respectively. Decreased radionuclide accumulation was seen primarily in areas extending from the anterior wall to the septum. Decreased radionuclide accumulation was smaller in extent and milder in degree in {sup 123}I-MIBG than in {sup 201}Tl imaging. These results suggest that even in patients without definite evidence of severe cardiac complications in conventional examinations, radionuclide imaging detects significant damage due to high-tension electrical injury, in which sympathetic nerve dysfunction might be milder than myocardial cell damage. (author)

  7. Elimination of bus voltage impact on temperature sensitive electrical parameter during turn-on transition for junction temperature estimation of high-power IGBT modules

    DEFF Research Database (Denmark)

    Luo, Haoze; Iannuzzo, Francesco; Blaabjerg, Frede

    2017-01-01

    Junction temperature is of great importance to safe operating area of IGBT modules. Various information of the IGBT operating state is reflected on electrical characteristics during turn-on transient. A unified extraction method for internal junction temperature via dynamic thermo-sensitive elect......Junction temperature is of great importance to safe operating area of IGBT modules. Various information of the IGBT operating state is reflected on electrical characteristics during turn-on transient. A unified extraction method for internal junction temperature via dynamic thermo......-sensitive electrical parameters (DTSEP) during turn-on transient is proposed. Two DTSEP, turn-on delay time (tdon) and the maximum increasing rate of collector current dic/dt(max), are combined to eliminate the bus voltage impact. Using the inherent emitter-auxiliary inductor LeE in high-power modules, the temperature...

  8. Integrated Electrokinetics-Adsorption Remediation of Saline-Sodic Soils: Effects of Voltage Gradient and Contaminant Concentration on Soil Electrical Conductivity

    Directory of Open Access Journals (Sweden)

    Mohammed Hussain Essa

    2013-01-01

    Full Text Available In this study, an integrated in situ remediation technique which couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic clay soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg, was used in this study to investigate the effects of voltage gradient, initial contaminant concentration, and polarity reversal rate on the soil electrical conductivity. Box-Behnken Design (BBD was used for the experimental design and response surface methodology (RSM was employed to model, optimize, and interpret the results obtained using Design-Expert version 8 platform. The total number of experiments conducted was 15 with voltage gradient, polarity reversal rate, and initial contaminant concentration as variables. The main target response discussed in this paper is the soil electrical conductivity due to its importance in electrokinetic remediation process. Responses obtained were fitted to quadratic models whose R2 ranges from 84.66% to 99.19% with insignificant lack of fit in each case. Among the investigated factors, voltage gradient and initial contaminant concentration were found to be the most significant influential factors.

  9. Integrated electrokinetics-adsorption remediation of saline-sodic soils: effects of voltage gradient and contaminant concentration on soil electrical conductivity.

    Science.gov (United States)

    Essa, Mohammed Hussain; Mu'azu, Nuhu Dalhat; Lukman, Salihu; Bukhari, Alaadin

    2013-01-01

    In this study, an integrated in situ remediation technique which couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic clay soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg), was used in this study to investigate the effects of voltage gradient, initial contaminant concentration, and polarity reversal rate on the soil electrical conductivity. Box-Behnken Design (BBD) was used for the experimental design and response surface methodology (RSM) was employed to model, optimize, and interpret the results obtained using Design-Expert version 8 platform. The total number of experiments conducted was 15 with voltage gradient, polarity reversal rate, and initial contaminant concentration as variables. The main target response discussed in this paper is the soil electrical conductivity due to its importance in electrokinetic remediation process. Responses obtained were fitted to quadratic models whose R (2) ranges from 84.66% to 99.19% with insignificant lack of fit in each case. Among the investigated factors, voltage gradient and initial contaminant concentration were found to be the most significant influential factors.

  10. Direct conversion of light-polarization information into electric voltage using photoinduced inverse spin-Hall effect in Pt/GaAs hybrid structure: Spin photodetector

    Science.gov (United States)

    Ando, K.; Morikawa, M.; Trypiniotis, T.; Fujikawa, Y.; Barnes, C. H. W.; Saitoh, E.

    2010-06-01

    The direct conversion of light-polarization information into electric voltage has been demonstrated using the photoinduced inverse spin-Hall effect in a Pt/GaAs hybrid structure. In the GaAs layer, spin-polarized carriers are generated by the illumination of circularly polarized light, which induces a pure-spin current in the Pt layer through the interface. The pure-spin current is converted into an electromotive force using the inverse spin-Hall effect (ISHE) in the Pt layer. The electromotive force due to the photoinduced ISHE was found to be proportional to the degree of circular polarization of the illuminated light outside the sample in spite of the presence of the Pt top layer, which is consistent with a calculation based on the analysis for light propagation in multilayer structures. This conversion of light-polarization information into electric voltage works at room temperature without bias voltage and magnetic fields, and thus can be used as a spin photodetector.

  11. Development of a Novel Bidirectional DC/DC Converter Topology with High Voltage Conversion Ratio for Electric Vehicles and DC-Microgrids

    Directory of Open Access Journals (Sweden)

    Ching-Ming Lai

    2016-05-01

    Full Text Available The main objective of this paper was to study a bidirectional direct current to direct current converter (BDC topology with a high voltage conversion ratio for electric vehicle (EV batteries connected to a dc-microgrid system. In this study, an unregulated level converter (ULC cascaded with a two-phase interleaved buck-boost charge-pump converter (IBCPC is introduced to achieve a high conversion ratio with a simpler control circuit. In discharge state, the topology acts as a two-stage voltage-doubler boost converter to achieve high step-up conversion ratio (48 V to 385 V. In charge state, the converter acts as two cascaded voltage-divider buck converters to achieve high voltage step-down conversion ratio (385 V to 48 V. The features, operation principles, steady-state analysis, simulation and experimental results are made to verify the performance of the studied novel BDC. Finally, a 500 W rating prototype system is constructed for verifying the validity of the operation principle. Experimental results show that highest efficiencies of 96% and 95% can be achieved, respectively, in charge and discharge states.

  12. [Alteration in bulbar conjunctiva microcirculation and interventional effect of Pentoxifylline after high-voltage electrical burn in rabbits].

    Science.gov (United States)

    Zhang, Qing-fu; Yan, Bao-yong; Zhou, Hui-min; Wang, Che-jiang

    2010-06-01

    To study the changes in bulbar conjunctiva microcirculation (BCM) and the therapeutic effect of Pentoxifylline on BCM disturbance after high-voltage electrical burn (HEB) in rabbits. Forty-five rabbits were divided into control group (C), electrical burn group (EB), and Pentoxifylline treatment group (PT) according to random number table, with 15 rabbits in each group. Model of HEB was reproduced in rabbits from EB and PT groups with voltage regulator and experimental transformer. Rabbits in C group were sham injured with the same devices without electrification. Changes in BCM were observed with microcirculation microscope at 15 minutes before HEB and 5 minutes, 1, 2, 4, 8 hour(s) post HEB (PHM or PHH), including: (1) morphology of microvessels, such as the discernible, diameters of arterioles, venules, and capillaries, the unevenness in caliber, and ischemic area; (2) dynamic changes in microvascular blood flow, such as blood flow speed in arterioles, venules, and capillaries, erythrocyte aggregation, and microthrombi formation; (3) condition of tissues surrounding microvessel, such as bleeding and exudation. Measurement data were processed with t test; enumeration data were processed with Fisher's exact test. (1) Morphology of microvessel: discernible of microvessels in EB and PT groups was decreased, but that of PT group was better than that of EB group. At PHM 5, diameter of arterioles, venules and capillaries was respectively (7.3+/-2.5), (12.3+/-2.4), (3.5+/-0.7) microm in EB group, all narrower than those of the control group [(14.6+/-3.1), (27.2+/-3.5), (9.0+/-1.4) microm, with t value respectively 5.23, 13.66, 14.04, P values all below 0.05]. Diameters of the microvessels in PT group [(10.2+/-3.8), (21.5+/-3.1), (7.1+/-1.2) microm] were larger than those in EB group (with t value respectively 2.21, 8.99, 10.18, P values all below 0.05). Diameters of arterioles, venules and capillaries in EB and PT groups recovered to the before HEB size at PHH 1. From PHH

  13. Does Stepwise Voltage Ramping Protect the Kidney from Injury During Extracorporeal Shockwave Lithotripsy? Results of a Prospective Randomized Trial.

    Science.gov (United States)

    Skuginna, Veronika; Nguyen, Daniel P; Seiler, Roland; Kiss, Bernhard; Thalmann, George N; Roth, Beat

    2016-02-01

    Renal damage is more frequent with new-generation lithotripters. However, animal studies suggest that voltage ramping minimizes the risk of complications following extracorporeal shock wave lithotripsy (SWL). In the clinical setting, the optimal voltage strategy remains unclear. To evaluate whether stepwise voltage ramping can protect the kidney from damage during SWL. A total of 418 patients with solitary or multiple unilateral kidney stones were randomized to receive SWL using a Modulith SLX-F2 lithotripter with either stepwise voltage ramping (n=213) or a fixed maximal voltage (n=205). SWL. The primary outcome was sonographic evidence of renal hematomas. Secondary outcomes included levels of urinary markers of renal damage, stone disintegration, stone-free rate, and rates of secondary interventions within 3 mo of SWL. Descriptive statistics were used to compare clinical outcomes between the two groups. A logistic regression model was generated to assess predictors of hematomas. Significantly fewer hematomas occurred in the ramping group(12/213, 5.6%) than in the fixed group (27/205, 13%; p=0.008). There was some evidence that the fixed group had higher urinary β2-microglobulin levels after SWL compared to the ramping group (p=0.06). Urinary microalbumin levels, stone disintegration, stone-free rate, and rates of secondary interventions did not significantly differ between the groups. The logistic regression model showed a significantly higher risk of renal hematomas in older patients (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.00-1.05; p=0.04). Stepwise voltage ramping was associated with a lower risk of hematomas (OR 0.39, 95% CI 0.19-0.80; p=0.01). The study was limited by the use of ultrasound to detect hematomas. In this prospective randomized study, stepwise voltage ramping during SWL was associated with a lower risk of renal damage compared to a fixed maximal voltage without compromising treatment effectiveness. Lithotripsy is a noninvasive

  14. Electrical injuries. Biological values measurements as a prediction factor of local evolution in electrocutions lesions.

    Science.gov (United States)

    Teodoreanu, R; Popescu, S A; Lascar, I

    2014-06-15

    Taking into account the incidence and the severity of electrocutions, we consider it extremely necessary to find effective, appropriate and particularized therapeutic solutions aimed at improving the survival, decreasing the mortality, ensuring a superior functional and aesthetic effect and facilitating the social reintegration. Given the severity of the general condition of the electrically injured patient and the fact that any worsening of the lesions has a systemic echo, the selection of the timing for re-excision is very important. The postponement of the surgical timing can break the precarious metabolic equilibrium and can hasten the installation of the multisystem organ failure (MSOF). The study is intended to establish a possible connection between the clinical evolution of the electrically injured patient and the dynamics of three important biological parameters, able to provide data concerning the therapeutic attitude to be followed. The patients with a diagnostic of high-voltage electrocution, who will be admitted to the Clinic, will be followed for a period of 2 years. The parameters to be followed daily will be: - Creatin-kinase, as a marker of muscular damage. - Hemoglobin, as a marker of tissue oxygenation. - Leukocytes, as an indicator of a possible septic evolution. The therapeutic alternatives, including the administration of antiplatelet drugs will be studied. In the period October 2010-June 2013 a total of 12 cases of high-voltage electrocution were admitted in our clinic. Among these, some could be placed in the study of 7 cases, as the remaining patients died within the first 24 hours of hospitalization due to the endured lesions. All the patients were admitted to the ICU ward that supported the treatment and monitoring until their stabilization, at which time they were transferred to the ward. All the patients received anti-thromboxane treatment from their admission (injectable NSAIDs associated with antisecretory drugs). By mutual agreement

  15. Lower extremity functional electrical stimulation cycling promotes physical and functional recovery in chronic spinal cord injury.

    Science.gov (United States)

    Sadowsky, Cristina L; Hammond, Edward R; Strohl, Adam B; Commean, Paul K; Eby, Sarah A; Damiano, Diane L; Wingert, Jason R; Bae, Kyongtae T; McDonald, John W

    2013-11-01

    To examine the effect of long-term lower extremity functional electrical stimulation (FES) cycling on the physical integrity and functional recovery in people with chronic spinal cord injury (SCI). Retrospective cohort, mean follow-up 29.1 months, and cross-sectional evaluation. Washington University Spinal Cord Injury Neurorehabilitation Center, referral center. Twenty-five people with chronic SCI who received FES during cycling were matched by age, gender, injury level, and severity, and duration of injury to 20 people with SCI who received range of motion and stretching. Lower extremity FES during cycling as part of an activity-based restorative treatment regimen. Change in neurological function: motor, sensory, and combined motor-sensory scores (CMSS) assessed by the American Spinal Injury Association Impairment scale. Response was defined as ≥ 1 point improvement. FES was associated with an 80% CMSS responder rate compared to 40% in controls. An average 9.6 CMSS point loss among controls was offset by an average 20-point gain among FES subjects. Quadriceps muscle mass was on average 36% higher and intra/inter-muscular fat 44% lower, in the FES group. Hamstring and quadriceps muscle strength was 30 and 35% greater, respectively, in the FES group. Quality of life and daily function measures were significantly higher in FES group. FES during cycling in chronic SCI may provide substantial physical integrity benefits, including enhanced neurological and functional performance, increased muscle size and force-generation potential, reduced spasticity, and improved quality of life.

  16. Directional movement of entomopathogenic nematodes in response to electrical fields: Effects of species, magnitude of voltage, and infective juvenile age

    Science.gov (United States)

    Entomopathogenic nematodes respond to a variety of stimuli when foraging. Previously, we reported a directional response to electrical fields for two entomopathogenic nematode species; specifically, when electrical fields were generated on agar plates Steinernema glaseri (a nematode that utilizes a...

  17. Controlled Operation of the Islanded Portion of the International Council on Large Electric Systems (CIGRE) Low Voltage Distribution Network

    DEFF Research Database (Denmark)

    Mustafa, Ghullam; Bak, Claus Leth; Ali, Ehsan

    2017-01-01

    is established by a VF controller. The voltage and the frequency of the islanded MG deviate when disconnected from the transmission grid and these deviations are caused by the load-generation imbalance. The voltage and the frequency of the islanded MG can be restored to the permissible limits if the desired......In islanding, a portion of the power network, comprised of the loads and distributed generation (DG) units, is isolated from the rest of the power grid and forms a micro grid (MG). In this condition, it becomes essential for the islanded MG to operate in a stable and controlled manner by providing...... ancillary services. When the MG is cut off from the main grid, the islanding must be detected by the DG units. In this condition it is essential that one of the controllers should be switched to the voltage-frequency (VF) control mode. In islanding, the network loses it slack reference and this reference...

  18. Tail nerve electrical stimulation induces body weight-supported stepping in rats with spinal cord injury.

    Science.gov (United States)

    Zhang, Shu-Xin; Huang, Fengfa; Gates, Mary; White, Jason; Holmberg, Eric G

    2010-03-30

    Walking or stepping has been considered the result from the activation of the central pattern generator (CPG). In most patients with spinal cord injury (SCI) the CPG is undamaged. To date, there are no noninvasive approaches for activating the CPG. Recently we developed a noninvasive technique, tail nerve electrical stimulation (TANES), which can induce positive hind limb movement of SCI rats. The purpose of this study is to introduce the novel technique and examine the effect of TANES on CPG activation. A 25 mm contusion injury was produced at spinal cord T10 of female, adult Long-Evans rats by using the NYU impactor device. Rats received TANES ( approximately 40 mA at 4 kHz) 7 weeks after injury. During TANES all injured rats demonstrated active body weight-supported stepping of hind limbs with left-right alternation and occasional front-hind coordination, resulting in significant, temporary increase in BBB scores (pfunctional electrical stimulation. Therefore the TANES may have considerable potential for achieving improvement of functional recovery in animal models and a similar method may be suggested for human study. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  19. Pulse trawl fishing: characteristics of the electrical stimulation and the effect on behaviour and injuries of Atlantic cod (Gadus morhua)

    NARCIS (Netherlands)

    Haan, de D.; Fosseidengen, J.E.; Fjelldal, P.G.; Burggraaf, D.; Rijnsdorp, A.D.

    2016-01-01

    In the North Sea flatfish fishery, electric pulse trawls have been introduced to replace the conventional mechanical method. Pulse trawls reduce the fuel consumption, reduce adverse impact on the ecosystem but cause injuries in gadoids. We describe the design and electrical properties of pulse

  20. Effect of electrical stimulation of hamstrings and L3/4 dermatome on gait in spinal cord injury

    NARCIS (Netherlands)

    van der Salm, Arjan; Veltink, Petrus H.; Hermens, Hermanus J.; Nene, A.V.; IJzerman, Maarten Joost

    2006-01-01

    Objective. To determine the effect of electrical stimulation of hamstrings and L3/4 dermatome on the swing phase of gait. Materials and Methods. Five subjects with incomplete spinal cord injury (SCI) with spasticity were included. Two electrical stimulation methods were investigated, i.e.,

  1. Electrically induced resistance training in individuals with motor complete spinal cord injury.

    Science.gov (United States)

    Ryan, Terence E; Brizendine, Jared T; Backus, Deborah; McCully, Kevin K

    2013-11-01

    To examine the effects of 16 weeks of electrically induced resistance training on insulin resistance and glucose tolerance, and changes in muscle size, composition, and metabolism in paralyzed muscle. Pre-post intervention. University-based trial. Participants (N=14; 11 men and 3 women) with chronic (>2y post spinal cord injury), motor complete spinal cord injury. Home-based electrically induced resistance exercise training twice weekly for 16 weeks. Plasma glucose and insulin throughout a standard clinical oral glucose tolerance test, thigh muscle and fat mass via dual-energy x-ray absorptiometry, quadriceps and hamstrings muscle size and composition via magnetic resonance imaging, and muscle oxidative metabolism using phosphorus magnetic resonance spectroscopy. Muscle mass increased in all participants (mean ± SD, 39%±27%; range, 5%-84%). The mean change ± SD in intramuscular fat was 3%±22%. Phosphocreatine mean recovery time constants ± SD were 102±24 and 77±18 seconds before and after electrical stimulation-induced resistance training, respectively (Pelectrical stimulation-induced resistance training increased muscle mass, but did not reduce intramuscular fat. Similarly, factors associated with insulin resistance or glucose tolerance did not improve with training. We did find a 25% improvement in mitochondrial function, as measured by phosphocreatine recovery rates. Larger improvements in mitochondrial function may translate into improved glucose tolerance and insulin resistance. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  2. Effect of Pulsed Electric Field on Membrane Lipids and Oxidative Injury of Salmonella typhimurium.

    Science.gov (United States)

    Yun, Ou; Zeng, Xin-An; Brennan, Charles S; Han, Zhong

    2016-08-22

    Salmonella typhimurium cells were subjected to pulsed electric field (PEF) treatment at 25 kV/cm for 0-4 ms to investigate the effect of PEF on the cytoplasmic membrane lipids and oxidative injury of cells. Results indicated that PEF treatment induced a decrease of membrane fluidity of Salmonella typhimurium (S. typhimuriumi), possibly due to the alterations of fatty acid biosynthesis-associated gene expressions (down-regulation of cfa and fabA gene expressions and the up-regulation of fabD gene expression), which, in turn, modified the composition of membrane lipid (decrease in the content ratio of unsaturated fatty acids to saturated fatty acids). In addition, oxidative injury induced by PEF treatment was associated with an increase in the content of malondialdehyde. The up-regulation of cytochrome bo oxidase gene expressions (cyoA, cyoB, and cyoC) indicated that membrane damage was induced by PEF treatment, which was related to the repairing mechanism of alleviating the oxidative injury caused by PEF treatment. Based on these results, we achieved better understanding of microbial injury induced by PEF, suggesting that micro-organisms tend to decrease membrane fluidity in response to PEF treatment and, thus, a greater membrane fluidity might improve the efficiency of PEF treatment to inactivate micro-organisms.

  3. Effect of Pulsed Electric Field on Membrane Lipids and Oxidative Injury of Salmonella typhimurium

    Directory of Open Access Journals (Sweden)

    Ou Yun

    2016-08-01

    Full Text Available Salmonella typhimurium cells were subjected to pulsed electric field (PEF treatment at 25 kV/cm for 0–4 ms to investigate the effect of PEF on the cytoplasmic membrane lipids and oxidative injury of cells. Results indicated that PEF treatment induced a decrease of membrane fluidity of Salmonella typhimurium (S. typhimuriumi, possibly due to the alterations of fatty acid biosynthesis-associated gene expressions (down-regulation of cfa and fabA gene expressions and the up-regulation of fabD gene expression, which, in turn, modified the composition of membrane lipid (decrease in the content ratio of unsaturated fatty acids to saturated fatty acids. In addition, oxidative injury induced by PEF treatment was associated with an increase in the content of malondialdehyde. The up-regulation of cytochrome bo oxidase gene expressions (cyoA, cyoB, and cyoC indicated that membrane damage was induced by PEF treatment, which was related to the repairing mechanism of alleviating the oxidative injury caused by PEF treatment. Based on these results, we achieved better understanding of microbial injury induced by PEF, suggesting that micro-organisms tend to decrease membrane fluidity in response to PEF treatment and, thus, a greater membrane fluidity might improve the efficiency of PEF treatment to inactivate micro-organisms.

  4. Exercise responses during functional electrical stimulation cycling in individuals with spinal cord injury.

    Science.gov (United States)

    Hasnan, Nazirah; Ektas, Nalan; Tanhoffer, Aldre Izabel P; Tanhoffer, Ricardo; Fornusek, Che; Middleton, James W; Husain, Ruby; Davis, Glen M

    2013-06-01

    This study compared acute exercise responses during arm cranking, functional electrical stimulation (FES)-assisted leg cycling, and combined arm and leg ("hybrid") cycling in individuals with spinal cord injury during maximal and submaximal exercise. Nine male subjects with long-standing neurological lesions from C7 to T12 were recruited. All subjects performed arm crank ergometry (ACE), FES leg cycle exercise (FES-LCE), combined ACE + FES-LCE, and cycling on a hybrid FES tricycle (HYBRID). They were assessed for their peak exercise responses in all four modalities. Subsequently, their submaximal heart rates (HR), cardiac outputs (Q), stroke volumes (SV), and arteriovenous oxygen extractions (Ca-Cv)O2 were measured at 40%, 60%, and 80% of mode-specific V˙O2peak. Arm exercise alone and arm + leg exercise resulted in significantly higher V˙O2peak and HRpeak compared with FES-LCE (P spinal cord injury population.

  5. Analysis of the Mechanisms Determining the Thermal and Electrical Properties of Epoxy Nanocomposites for High Voltage Applications

    NARCIS (Netherlands)

    Tsekmes, I.A.

    2016-01-01

    The addition of microsized fillers to polymers, in order to tailor their properties, has been extensively used in many industrial applications since the 1960s. The same approach applies to the field of electrical insulation. Epoxy resin is a widely used polymer in the electrical power sector, but it

  6. High voltage test techniques

    CERN Document Server

    Kind, Dieter

    2001-01-01

    The second edition of High Voltage Test Techniques has been completely revised. The present revision takes into account the latest international developments in High Voltage and Measurement technology, making it an essential reference for engineers in the testing field.High Voltage Technology belongs to the traditional area of Electrical Engineering. However, this is not to say that the area has stood still. New insulating materials, computing methods and voltage levels repeatedly pose new problems or open up methods of solution; electromagnetic compatibility (EMC) or components and systems al

  7. Analysis of non-ohmic electrical current-voltage characteristic of membranes carrying a single track-etched conical pore

    CERN Document Server

    Woermann, D

    2002-01-01

    The model of the membrane with narrow pores is used to rationalise the existence of a non-ohmic current-voltage characteristic of membranes carrying a single narrow conical pore. The observation of this characteristic was reported recently by Apel et al. [Nucl. Instr. and Meth. B 184 (2001) 366]. The membranes used in that study were produced by an advanced track etch technique.

  8. Capacitance–voltage analysis of electrical properties for WSe2 field effect transistors with high-k encapsulation layer

    Science.gov (United States)

    Ko, Seung-Pil; Shin, Jong Mok; Jang, Ho Kyun; You, Min Youl; Jin, Jun-Eon; Choi, Miri; Cho, Jiung; Kim, Gyu-Tae

    2018-02-01

    Doping effects in devices based on two-dimensional (2D) materials have been widely studied. However, detailed analysis and the mechanism of the doping effect caused by encapsulation layers has not been sufficiently explored. In this work, we present experimental studies on the n-doping effect in WSe2 field effect transistors (FETs) with a high-k encapsulation layer (Al2O3) grown by atomic layer deposition. In addition, we demonstrate the mechanism and origin of the doping effect. After encapsulation of the Al2O3 layer, the threshold voltage of the WSe2 FET negatively shifted with the increase of the on-current. The capacitance–voltage measurements of the metal insulator semiconductor (MIS) structure proved the presence of the positive fixed charges within the Al2O3 layer. The flat-band voltage of the MIS structure of Au/Al2O3/SiO2/Si was shifted toward the negative direction on account of the positive fixed charges in the Al2O3 layer. Our results clearly revealed that the fixed charges in the Al2O3 encapsulation layer modulated the Fermi energy level via the field effect. Moreover, these results possibly provide fundamental ideas and guidelines to design 2D materials FETs with high-performance and reliability.

  9. A Comparative Study of Electric Load Curve Changes in an Urban Low-Voltage Substation in Spain during the Economic Crisis (2008–2013)

    Science.gov (United States)

    Lara-Santillán, Pedro M.; Mendoza-Villena, Montserrat; Fernández-Jiménez, L. Alfredo; Mañana-Canteli, Mario

    2014-01-01

    This paper presents a comparative study of the electricity consumption (EC) in an urban low-voltage substation before and during the economic crisis (2008–2013). This low-voltage substation supplies electric power to near 400 users. The EC was measured for an 11-year period (2002–2012) with a sampling time of 1 minute. The study described in the paper consists of detecting the changes produced in the load curves of this substation along the time due to changes in the behaviour of consumers. The EC was compared using representative curves per time period (precrisis and crisis). These representative curves were obtained after a computational process, which was based on a search for days with similar curves to the curve of a determined (base) date. This similitude was assessed by the proximity on the calendar, day of the week, daylight time, and outdoor temperature. The last selection parameter was the error between the nearest neighbour curves and the base date curve. The obtained representative curves were linearized to determine changes in their structure (maximum and minimum consumption values, duration of the daily time slot, etc.). The results primarily indicate an increase in the EC in the night slot during the summer months in the crisis period. PMID:24895677

  10. A Comparative Study of Electric Load Curve Changes in an Urban Low-Voltage Substation in Spain during the Economic Crisis (2008–2013

    Directory of Open Access Journals (Sweden)

    Pedro M. Lara-Santillán

    2014-01-01

    Full Text Available This paper presents a comparative study of the electricity consumption (EC in an urban low-voltage substation before and during the economic crisis (2008–2013. This low-voltage substation supplies electric power to near 400 users. The EC was measured for an 11-year period (2002–2012 with a sampling time of 1 minute. The study described in the paper consists of detecting the changes produced in the load curves of this substation along the time due to changes in the behaviour of consumers. The EC was compared using representative curves per time period (precrisis and crisis. These representative curves were obtained after a computational process, which was based on a search for days with similar curves to the curve of a determined (base date. This similitude was assessed by the proximity on the calendar, day of the week, daylight time, and outdoor temperature. The last selection parameter was the error between the nearest neighbour curves and the base date curve. The obtained representative curves were linearized to determine changes in their structure (maximum and minimum consumption values, duration of the daily time slot, etc.. The results primarily indicate an increase in the EC in the night slot during the summer months in the crisis period.

  11. Quantification of ventilation distribution in regional lung injury by electrical impedance tomography and xenon computed tomography.

    Science.gov (United States)

    Elke, Gunnar; Fuld, Matthew K; Halaweish, Ahmed F; Grychtol, Bartłomiej; Weiler, Norbert; Hoffman, Eric A; Frerichs, Inéz

    2013-10-01

    Validation studies of electrical impedance tomography (EIT) based assessment of regional ventilation under pathological conditions are required to prove that EIT can reliably quantify heterogeneous ventilation distribution with sufficient accuracy. The objective of our study was to validate EIT measurements of regional ventilation through a comparison with xenon-multidetector-row computed tomography (XeCT) in an animal model of sub-lobar lung injury. Nine anesthetized mechanically ventilated supine pigs were examined before and after the induction of lung injury in two adjacent sub-lobar segments of the right lung by saline lavage or endotoxin instillation. Regional ventilation was determined in 32 anteroposterior regions of interest in the right and left lungs and the ventilation change quantified by difference images between injury and control. Six animals were included in the final analysis. Measurements of regional ventilation by EIT and XeCT correlated well before (rs = 0.89 right, rs = 0.90 left lung) and after local injury (rs = 0.79 and 0.92, respectively). No bias and narrow limits of agreement were found during both conditions. The ventilation decrease in the right injured lung was correspondingly measured by both modalities (5.5%±1.1% by EIT and 5.4%±1.9% by XeCT, p = 0.94). EIT was inferior to clearly separate the exact anatomical location of the regional injuries. Regional ventilation was overestimated (<2%) in the most ventral and dorsal regions and underestimated (2%) in the middle regions by EIT compared to XeCT. This study shows that EIT is able to reliably discern even small ventilation changes on sub-lobar level.

  12. Comparing a single institution's experience with electrical injuries to the data recorded in the National Burn Repository.

    Science.gov (United States)

    Matt, Sarah E; Shupp, Jeffery W; Carter, Elizabeth A; Shaw, Jesse D; Jordan, Marion H

    2012-01-01

    Electrical injuries usually represent a small proportion of a burn center's admissions. Although burn size may be small, internal tissue damage is sometimes extensive. This study reviews a single institution's experience with electrical injuries and compares it to the multi-institutional data of the National Burn Repository (NBR). The 2009 NBR and the records of a large urban burn center (single institution) were queried for adult electrical injuries over an 8-year period. Data examined included demographics, %TBSA burn, length of stay (LOS), injury circumstance, and disposition. Multiple linear regression models were created to determine factors related to LOS. One hundred ninety-one single-institution patients and 2837 multi-institution patients met the criteria. Both cohorts were mostly white males approximately 30 years of age and injuries where often work-related. Single-institution patients had a mean injury size of 4% TBSA, while multi-institution patients had 7%. The most common exposure source was domestic wiring for single-institution patients and electrical power plants/lines for multi-institution patients. Single-institution data showed that females had a shorter LOS than males (P institution data showed that independent risk factors for an increased LOS were infection, amputation, fasciotomy, and being Hispanic. Independent risk factors for multi-institution patients were being Hispanic and large %TBSA burn. There was no difference in mortality, gender, age, LOS, or intensive care unit LOS between the cohorts. In this analysis, there was no statistical difference between outcomes in the single- or multi-institutional groups. However, injuries reported in the NBR were slightly larger. In both cohorts, an increase in LOS was associated with %TBSA, as expected. Interestingly, Hispanic ethnicity correlated with an increased LOS. Future work will be aimed at understanding this correlation to determine whether it is specific to electrical injury or burns in

  13. Electrical impedance tomography compared with thoracic computed tomography during a slow inflation maneuver in experimental models of lung injury.

    Science.gov (United States)

    Wrigge, Hermann; Zinserling, Jörg; Muders, Thomas; Varelmann, Dirk; Günther, Ulf; von der Groeben, Cornelius; Magnusson, Anders; Hedenstierna, Göran; Putensen, Christian

    2008-03-01

    To determine the validity of functional electric impedance tomography to monitor regional ventilation distribution in experimental acute lung injury, and to develop a simple electric impedance tomography index detecting alveolar recruitment. Randomized prospective experimental study. Academic research laboratory. Sixteen anesthetized, tracheotomized, and mechanically ventilated pigs. Acute lung injury was induced either by acid aspiration (direct acute lung injury) or by abdominal hypertension plus oleic acid injection (indirect acute lung injury) in ten pigs. Six pigs with normal lungs were studied as a control group and with endotracheal suction-related atelectasis. After 4 hrs of mechanical ventilation, a slow inflation was performed. During slow inflation, simultaneous measurements of regional ventilation by electric impedance tomography and dynamic computed tomography were highly correlated in quadrants of a transversal thoracic plane (r2 = .63-.88, p Electric impedance tomography indexes to detect alveolar recruitment were determined by mathematical curve analysis of regional impedance time curves. Empirical tests of different methods revealed that regional ventilation delay, that is, time delay of regional impedance time curve to reach a threshold, correlated well with recruited volume as measured by CT (r2 = .63). Correlation coefficients in subgroups were r2 = .71 and r2 = .48 in pigs with normal lungs with and without closed suction related atelectasis and r2 = .79 in pigs subject to indirect acute lung injury, respectively, whereas no significant correlation was found in pigs undergoing direct acute lung injury. Electric impedance tomography allows assessment of regional ventilation distribution and recruitment in experimental models of direct and indirect acute lung injury as well as normal lungs. Except for pigs with direct acute lung injury, regional ventilation delay determined during a slow inflation from impedance time curves appears to be a simple

  14. Functional electrical stimulation cycling in youth with spinal cord injury: A review of intervention studies.

    Science.gov (United States)

    Mayson, Tanja A; Harris, Susan R

    2014-05-01

    Preliminary research suggests that functional electrical stimulation cycling (FESC) might be a promising intervention for youth with spinal cord injury (SCI). To review the evidence on FESC intervention in youth with SCI. Systematic literature searches were conducted during December 2012. Two reviewers independently selected titles, abstracts, and full-text articles. Of 40 titles retrieved, six intervention studies met inclusion criteria and were assessed using American Academy for Cerebral Palsy and Developmental Medicine Levels of Evidence and Conduct Questions for Group Design. The study results were tabulated based on levels of evidence, with outcomes categorized according to the International Classification of Functioning, Disability, and Health framework. Evidence from the six included studies suggests that FESC is safe for youth with SCI, with no increase in knee/hip injury or hip displacement. Results from one level II randomized controlled trial suggest that a thrice weekly, 6-month FESC program can positively influence VO2 levels when compared with passive cycling, as well as quadriceps strength when compared with electrical stimulation and passive cycling. FESC demonstrates limited yet encouraging results as a safe modality to mitigate effects of inactivity in youth with SCI. More rigorous research involving a greater number of participants is needed before clinicians can be confident of its effectiveness.

  15. Four weeks of functional electrical stimulated cycling after spinal cord injury: a clinical cohort study.

    Science.gov (United States)

    Kuhn, Daniel; Leichtfried, Veronika; Schobersberger, Wolfgang

    2014-09-01

    The aim of this study was to determine the efficacy and the effects of functional electrical stimulated cycling (FES cycling) in patients with spinal cord injury during their rehabilitation in a special acute care unit. Thirty patients [10 with American Spinal Injury Association Impairment Scale (AIS) grade A, three with AIS grade B, 15 with AIS grade C, two with AIS grade D] aged 44±15.5 years and 2 (median) (interquartile range, 1.0-4.25) months after spinal cord injury were included in the study. The patients participated in a 20-min FES-cycling program 2 days per week for 4 weeks during their acute inpatient rehabilitation. The influence on muscle cross-section, muscle and leg circumference, spasticity, and the walking ability parameter (distance, time, aids) was measured. Muscle stimulation intensity and output parameters (pedalling time and distance) were also recorded. Spasticity decreased during hip abduction and adduction (70 and 98.1%, respectively). Spasticity during knee flexion and knee extension decreased by 66.8 and 76.6%, and a decrease was found during dorsal foot extension (67.8%; for all, Pfunction-oriented physiotherapy and occupational therapy can have a positive influence on spasticity, walking ability, and muscular reactivation. It seems to support circulatory processes within the rehabilitation of paraplegics already after a 4-week intervention.

  16. Electrical isolation of the superior vena cava using upstream phrenic pacing to avoid phrenic nerve injury.

    Science.gov (United States)

    Kimura, Takehiro; Takatsuki, Seiji; Fukumoto, Kotaro; Nishiyama, Nobuhiro; Sato, Yuriko; Aizawa, Yoshiyasu; Fukuda, Yukiko; Sato, Toshiaki; Miyoshi, Shunichiro; Fukuda, Keiichi

    2012-09-01

    Phrenic nerve (PN) injury is a potential complication that can occur during superior vena cava (SVC) isolation to cure atrial fibrillation (AF). Avoiding radiofrequency (RF) energy delivery is the safer alternative but may result in failed isolation. High-output PN pacing above the ablation site (upstream PN pacing) to confirm whether the PN is intact is a promising technique to avoid PN injury. This study was conducted to elucidate the safety of delivering RF energy at the site of capture of the right PN using upstream high-output pacing during electrical SVC isolation. SVC isolation was conducted in 41 drug-resistant AF patients. When high-output pacing (25 mA) from the distal tip of the ablation catheter captured the PN at the right atrial-SVC junction, upstream PN pacing (cycle length: 1000-1500 ms) was applied during RF delivery. The application of RF energy was stopped upon the failure or weakness of diaphragmatic twitching. The feasibility of SVC isolation using upstream PN pacing was investigated. In all 41 patients, SVC isolation was successfully achieved. RF energy was delivered at the PN capture site in 26 patients (154 ± 138 second, 18 ± 5 W), and upstream PN pacing was successfully applied in all of the patients. Out of 46 SVC isolations, including five repeated sessions, PN injury occurred in one patient, who recovered spontaneously within 2 weeks. Upstream PN pacing may be effective for the safe completion of SVC isolation and to reduce the severity of PN injury. ©2012, The Authors. Journal compilation ©2012 Wiley Periodicals, Inc.

  17. Semiconditional Electrical Stimulation of Pudendal Nerve Afferents Stimulation to Manage Neurogenic Detrusor Overactivity in Patients with Spinal Cord Injury

    OpenAIRE

    Lee, Young-Hee; Kim, Jung Moon; Im, Hyung Tae; Lee, Kye-Wook; Kim, Sung Hoon; Hur, Dong Min

    2011-01-01

    Objective To evaluate the effect of semiconditional electrical stimulation of the pudendal nerve afferents for the neurogenic detrusor overactivity in patients with spinal cord injury. Forty patients (36 males, 4 males) with spinal cord injury who had urinary incontinence and frequency, as well as felt bladder contraction with bladder filling sense or autonomic dysreflexic symptom participated in this study. Method Patients with neurogenic detrusor overactivity were subdivided into complete i...

  18. Phase Balancing by Means of Electric Vehicles Single-Phase Connection Shifting in a Low Voltage Danish Grid

    DEFF Research Database (Denmark)

    Lico, Pasqualino; Marinelli, Mattia; Knezovic, Katarina

    2015-01-01

    In Denmark, household consumers are supplied with three phase with neutral cable. In addition, the distribution service operator cannot decide to which phase electrical appliance are connected. The technician who realizes the installation connects the loads according to his technical expertise....... This may results in heavy imbalances. This paper uses a real Danish distribution system with household consumers, photovoltaic installation and electrical vehicles (EV). In this paper the possibility to use EVs’ charging spots in order to reduce grid’s imbalances will be investigated. Usually, charging...

  19. [Changes in the expression of large-conductance calcium-activated potassium channels in dorsal root ganglion neurons after electrical injury in rats' sciatic nerves and its influence on sensory conduction function].

    Science.gov (United States)

    Wang, Guangning; Li, Xueyong; Xu, Xiaoli; Ren, Pan

    2016-06-01

    To study the changes in the expression of large-conductance calcium-activated potassium (BKCa) channels in dorsal root ganglion (DRG) neurons after electrical injury in rats' sciatic nerves and its influence on sensory conduction function. One-hundred and thirty-six adult SD rats were divided into normal control group, sham electrical injury group, and 75, 100, 125 V electrical injury groups according to the random number table, with 8 rats in normal control group and 32 rats in each of the rest 4 groups. Rats in normal control group were routinely fed without any treatment. Blunt dissection of the sciatic nerves of left hind leg of rats was performed in sham electrical injury group, while sciatic nerves of left hind leg of rats in electrical injury groups were electrically injured with corresponding voltage. Eight rats of normal control group fed for one week, and 8 rats from each of the rest four groups on post injury day (PID) 3 and in post injury week (PIW) 1, 2, 3 respectively were collected to detect the paw withdrawal mechanical threshold (PWMT). In addition, rats of 100 V electrical injury group in PIW 1 were collected and intrathecally injected with NS1619 after former PWMT detection, and PWMT was detected per 30 minutes within three hours post injection. The rats in each group at each time point were sacrificed after PWMT detection. The DRG of L4 to L6 segments of spinal cord was sampled to observe the BKCa channels distribution with immunohistochemical staining and to detect the protein and mRNA expressions of BKCa channels with Western blotting and reverse transcription-polymerase chain reaction respectively. Data were processed with one-way analysis of variance, analysis of variance of factorial design, and SNK test. (1) The PWMT values of rats in 75 and 100 V electrical injury groups on PID 3 and in PIW 1, 2, 3 were (5.8±0.6), (5.0±0.8), (4.2±0.3), (5.9±1.1) g; (5.3±1.3), (5.9±2.0), (4.5±2.7), (4.3±1.3) g, respectively, which were

  20. Efficacy and Safety of Strict Voltage-based Substrate Mapping and Radiofrequency Catheter Ablation in Electrical Storms—Review of Substrate-mapping Guided Ablation in Frequent Appropriate Shocks

    OpenAIRE

    Arimoto, Takanori; Tada, Hiroshi; Sekiguchi, Yukio; Koyama, Takashi; Igarashi, Miyako; Yamasaki, Hiro; Machino, Takeshi; Kuroki, Kenji; Kuga, Keisuke; Aonuma, Kazutaka

    2009-01-01

    Background: We investigated the efficacy and safety of strict voltage-based substrate mapping and radiofrequency catheter ablation (SV-substrate-map ablation) in patients with electrical storm. Methods and Results: SV-substrate-map ablation was performed in 15 patients suffering from multiple appropriate shocks (6.0 ± 3.8/day) from implantable cardioverter defibrillators (ICDs). Strict voltage criteria were defined as: non-arrhythmogenic areas, >0.6mV; low voltage areas, >0.1 to ≤0.6 mV; a...

  1. High-Voltage Thermionic Reactor Using Double-Sheath Fuel Elements, 3rd Interational Electrical Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1972-06-01

    A novel design concept for a "flashlight-type" in-core thermionic reactor is described. This concept, called the "double-sheath" design in contrast to the previously considered "wet-sheath" and "dry-sheath" concepts, permits the build-up of high reactor output voltages, without the danger of cesium breakdown and shorts-to-ground. In addition to a description of the design and its functional components, a brief discussion of suggested fuel element fabrication and reactor assembly techniques is presented. The proposed design offers the potential of high reliability because only insulators at very low potentials (e.g.<3 volts) are in contact with cesium vapor; because there are no ceramic or cermet seals within the reactor (all are outside, beyond the reflectors); and because all vacuum-tight joints in the reactor are between ductile niobium components.

  2. Breakdown voltage at the electric terminals of GCFR-core flow test loop fuel rod simulators in helium and air

    Energy Technology Data Exchange (ETDEWEB)

    Huntley, W.R.; Conley, T.B.

    1979-12-01

    Tests were performed to determine the ac and dc breakdown voltage at the terminal ends of a fuel rod simulator (FRS) in helium and air atmospheres. The tests were performed at low pressures (1 to 2 atm) and at temperatures from 20 to 350/sup 0/C (68 to 660/sup 0/F). The area of concern was the 0.64-mm (0.025-in.) gap between the coaxial conductor of the FRS and the sheaths of the four internal thermocouples as they exit the FRS. The tests were prformed to ensure a sufficient safety margin during Core Flow Test Loop (CFTL) operations that require potentials up to 350 V ac at the FRS terminals. The primary conclusion from the test results is that the CFTL cannot be operated safely if the terminal ends of the FRSs are surrounded by a helium atmosphere but can be operated safely in air.

  3. Impact of p-body length on the electrical characteristics of high-voltage MOSFET with a lateral asymmetric channel

    Science.gov (United States)

    Baek, Ki-Ju; Na, Kee-Yeol; Lee, Young-Jun; Kim, Yeong-Seuk

    2015-01-01

    This paper presents the geometric effects of a lateral asymmetric channel (LAC) structure for high-voltage (HV) MOSFETs. The LAC structure was adopted to enhance the device performance by modifying the potential distribution in the channel and reducing the parasitic transistor effect. The LAC structure was realized using a p-body doping region inside the channel for the HV device. The effects of the p-body length were examined. The experiments showed that the p-body length is a key parameter for device optimization considering circuit applications. The HV LAC device with a shorter p-body length showed transconductance (gm) improvement and on-resistance (RON) reduction. The maximized output resistance (rout) was obtained when the p-body length was approximately half of the channel length.

  4. Intrinsic oscillatory activity arising within the electrically coupled AII amacrine–ON cone bipolar cell network is driven by voltage-gated Na+ channels

    Science.gov (United States)

    Trenholm, Stuart; Borowska, Joanna; Zhang, Jiawei; Hoggarth, Alex; Johnson, Kyle; Barnes, Steven; Lewis, Timothy J; Awatramani, Gautam B

    2012-01-01

    In the rd1 mouse model for retinal degeneration, the loss of photoreceptors results in oscillatory activity (∼10–20 Hz) within the remnant electrically coupled network of retinal ON cone bipolar and AII amacrine cells. We tested the role of hyperpolarization-activated currents (Ih), voltage-gated Na+ channels and gap junctions in mediating such oscillatory activity. Blocking Ih (1 mm Cs+) hyperpolarized the network and augmented activity, while antagonizing voltage-dependent Na+ channels (1 μm TTX) abolished oscillatory activity in the AII amacrine–ON cone bipolar cell network. Voltage-gated Na+ channels were only observed in AII amacrine cells, implicating these cells as major drivers of activity. Pharmacologically uncoupling the network (200 μm meclofenamic acid (MFA)) blocked oscillations in all cells indicating that Na+ channels exert their influence over multiple cell types within the network. In wt retina, occluding photoreceptor inputs to bipolar cells (10 μm NBQX and 50 μm l-AP4) resulted in a mild (∼10 mV) hyperpolarization and the induction of oscillatory activity within the AII amacrine–ON cone bipolar cell network. These oscillations had similar properties to those observed in rd1 retina, suggesting that no major degeneration-induced network rewiring is required to trigger spontaneous oscillations. Finally, we constructed a simplified computational model that exhibited Na+ channel-dependent network oscillations. In this model, mild heterogeneities in channel densities between individual neurons reproduced our experimental findings. These results indicate that TTX-sensitive Na+ channels in AII amacrine cells trigger degeneration-induced network oscillations, which provide a persistent synaptic drive to downstream remnant neurons, thus appearing to replace photoreceptors as the principal drivers of retinal activity. PMID:22393249

  5. A facile approach for reducing the working voltage of Au/TiO2/Au nanostructured memristors by enhancing the local electric field

    Science.gov (United States)

    Arab Bafrani, Hamidreza; Ebrahimi, Mahdi; Bagheri Shouraki, Saeed; Moshfegh, Alireza Z.

    2018-01-01

    Memristor devices have attracted tremendous interest due to different applications ranging from nonvolatile data storage to neuromorphic computing units. Exploring the role of surface roughness of the bottom electrode (BE)/active layer interface provides useful guidelines for the optimization of the memristor switching performance. This study focuses on the effect of surface roughness of the BE electrode on the switching characteristics of Au/TiO2/Au three-layer memristor devices. An optimized wet-etching treatment condition was found to modify the surface roughness of the Au BE where the measurement results indicate that the roughness of the Au BE is affected by both duration time and solution concentrations of the wet-etching process. Then we fabricated arrays of TiO2-based nanostructured memristors sandwiched between two sets of cross-bar Au electrode lines (junction area 900 μm2). The results revealed a reduction in the working voltages in current–voltage characteristic of the device performance when increasing the surface roughness at the Au(BE)/TiO2 active layer interface. The set voltage of the device (Vset) significantly decreased from 2.26–1.93 V when we increased the interface roughness from 4.2–13.1 nm. The present work provides information for better understanding the switching mechanism of titanium-dioxide-based devices, and it can be inferred that enhancing the roughness of the Au BE/TiO2 active layer interface leads to a localized non-uniform electric field distribution that plays a vital role in reducing the energy consumption of the device.

  6. Intrinsic oscillatory activity arising within the electrically coupled AII amacrine-ON cone bipolar cell network is driven by voltage-gated Na+ channels.

    Science.gov (United States)

    Trenholm, Stuart; Borowska, Joanna; Zhang, Jiawei; Hoggarth, Alex; Johnson, Kyle; Barnes, Steven; Lewis, Timothy J; Awatramani, Gautam B

    2012-05-15

    In the rd1 mouse model for retinal degeneration, the loss of photoreceptors results in oscillatory activity (∼10–20 Hz) within the remnant electrically coupled network of retinal ON cone bipolar and AII amacrine cells. We tested the role of hyperpolarization-activated currents (I(h)), voltage-gated Na(+) channels and gap junctions in mediating such oscillatory activity. Blocking I(h) (1 mm Cs(+)) hyperpolarized the network and augmented activity, while antagonizing voltage-dependent Na(+) channels (1 μm TTX) abolished oscillatory activity in the AII amacrine-ON cone bipolar cell network. Voltage-gated Na(+) channels were only observed in AII amacrine cells, implicating these cells as major drivers of activity. Pharmacologically uncoupling the network (200 μm meclofenamic acid (MFA)) blocked oscillations in all cells indicating that Na(+) channels exert their influence over multiple cell types within the network. In wt retina, occluding photoreceptor inputs to bipolar cells (10 μm NBQX and 50 μm l-AP4) resulted in a mild (∼10 mV) hyperpolarization and the induction of oscillatory activity within the AII amacrine-ON cone bipolar cell network. These oscillations had similar properties to those observed in rd1 retina, suggesting that no major degeneration-induced network rewiring is required to trigger spontaneous oscillations. Finally, we constructed a simplified computational model that exhibited Na(+) channel-dependent network oscillations. In this model, mild heterogeneities in channel densities between individual neurons reproduced our experimental findings. These results indicate that TTX-sensitive Na(+) channels in AII amacrine cells trigger degeneration-induced network oscillations, which provide a persistent synaptic drive to downstream remnant neurons, thus appearing to replace photoreceptors as the principal drivers of retinal activity.

  7. Assessment of duration of the drive operation in the mode of kinetic energy recovery under power supply voltage sags in electrical grids of mechanical engineering enterprises

    Science.gov (United States)

    Shonin, O. B.; Novozhilov, N. G.

    2017-02-01

    Voltage sags in electric grids of mechanical engineering enterprises may lead to disconnection of important power consumers with variable frequency drives from the power grid and further interruption of the production process. The paper considers a sensorless V/f control system of еру induction motor drive under normal conditions and under voltage sags on the basis of a computer model of the drive and derivation of a formula for assessment of possible duration of the drive operation in the mode of controlled recovery of kinetic energy accumulated in rotating mass of the drive. Results of simulations have been used to validate results of calculations of the rotor velocity deceleration made in a closed form obtained from the equation reflecting the balance of torques. It is shown that results of calculations practically coincide with results of simulations in the range up to 5% of the velocity initial value. The proposed formula may be useful for estimation of the duration of the drive operation in the mode of recovery of kinetic energy depending on parameters of the motor and driven mechanisms.

  8. Inverted Fuel Cell: Room-Temperature Hydrogen Separation from an Exhaust Gas by Using a Commercial Short-Circuited PEM Fuel Cell without Applying any Electrical Voltage.

    Science.gov (United States)

    Friebe, Sebastian; Geppert, Benjamin; Caro, Jürgen

    2015-06-26

    A short-circuited PEM fuel cell with a Nafion membrane has been evaluated in the room-temperature separation of hydrogen from exhaust gas streams. The separated hydrogen can be recovered or consumed in an in situ olefin hydrogenation when the fuel cell is operated as catalytic membrane reactor. Without applying an outer electrical voltage, there is a continuous hydrogen flux from the higher to the lower hydrogen partial pressure side through the Nafion membrane. On the feed side of the Nafion membrane, hydrogen is catalytically split into protons and electrons by the Pt/C electrocatalyst. The protons diffuse through the Nafion membrane, the electrons follow the short-circuit between the two brass current collectors. On the cathode side, protons and electrons recombine, and hydrogen is released. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Stray voltage mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Jamali, B.; Piercy, R.; Dick, P. [Kinetrics Inc., Toronto, ON (Canada). Transmission and Distribution Technologies

    2008-04-09

    This report discussed issues related to farm stray voltage and evaluated mitigation strategies and costs for limiting voltage to farms. A 3-phase, 3-wire system with no neutral ground was used throughout North America before the 1930s. Transformers were connected phase to phase without any electrical connection between the primary and secondary sides of the transformers. Distribution voltage levels were then increased and multi-grounded neutral wires were added. The earth now forms a parallel return path for the neutral current that allows part of the neutral current to flow continuously through the earth. The arrangement is responsible for causing stray voltage. Stray voltage causes uneven milk production, increased incidences of mastitis, and can create a reluctance to drink water amongst cows when stray voltages are present. Off-farm sources of stray voltage include phase unbalances, undersized neutral wire, and high resistance splices on the neutral wire. Mitigation strategies for reducing stray voltage include phase balancing; conversion from single to 3-phase; increasing distribution voltage levels, and changing pole configurations. 22 refs., 5 tabs., 13 figs.

  10. Electrocution-related mortality: a review of 71 deaths by low-voltage electrical current in Guangdong, China, 2001-2010.

    Science.gov (United States)

    Liu, Shuiping; Yu, Yangeng; Huang, Quanyong; Luo, Bin; Liao, Xinbiao

    2014-09-01

    The aim of this study was to investigate the epidemiological characteristics of low-voltage electrocution deaths in Guangdong, China. Three thousand three hundred seventy autopsy reports from the Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, over a period of 10 years (2001-2010) were reviewed, of which 71 low-voltage electrocution cases were identified. The descriptive statistical analyses were carried out with the application of SPSS 19.0 software. Electrocution accounted for 2.11% of all autopsied cases. The age range was 3 to 57 years with a mean age of 31.77 ± 11.0 years. The average age of male victims was 33.08 ± 10.77 years, and that of female victims was 22.63 ± 11.06 years. The majority of the victims (87.33%) were male. Among the circumstances leading to electrocution, most of them occurred in factory and in the street. Considering the contact details, deaths were caused most frequently by touching electrical wires (n = 27, 38.02%), followed by touching charged machine (n = 20, 28.17%). There were no suicide and homicide cases. Of all electrocution cases, 50.70% occurred during the summer period from June through August. The upper extremity was the most frequently involved contact site (59.72%). No electrical burn marks were present in 14 cases (19.72%). Our results indicated that most deaths from electrocution occur more often in factories, in summer seasons, and to young male workers, which can help in the development of a differentiated strategy for the prevention of electrocution, while taking into consideration sex, age, occupation, and season of the year.

  11. Analysis of Electric Propulsion Performance on Submersible with Motor DC, Supply Power 10260AH at Voltage 115VDC

    Directory of Open Access Journals (Sweden)

    Indra Ranu Kusuma

    2017-03-01

    Full Text Available Electric propulsion is the ship system using propulsion motor to replace performance of main engine. The application of diesel engine as propulsion system have some problems and weaknesses such as diesel engine unability to operate when submersible vessel is operating under sea. To overcome that problems in submersible vessel, alternative solution of ship propulsion is required. DC Motor can be used as this alternative solution. Submersible vessel use electric propulsion system with DC Motor because DC Motor has advantages of easy rotation setting and does not cause noise when submersible vessel is diving. This bachelor thesis will study the application of DC Motor as an electric propulsion system on submersible vessel with length 59,57 m in series and parallel circuit by simulation using MATLAB software. The simulation data obtained are rotation and torque of DC Motor. From these simulation, it can be concluded that parallel circuit rotation is greater than series circuit rotation. It caused the greater speed and lower power in parallel circuit. 

  12. Functional electrical stimulation after spinal cord injury: current use, therapeutic effects and future directions.

    Science.gov (United States)

    Ragnarsson, K T

    2008-04-01

    Repair of the injured spinal cord by regeneration therapy remains an elusive goal. In contrast, progress in medical care and rehabilitation has resulted in improved health and function of persons with spinal cord injury (SCI). In the absence of a cure, raising the level of achievable function in mobility and self-care will first and foremost depend on creative use of the rapidly advancing technology that has been so widely applied in our society. Building on achievements in microelectronics, microprocessing and neuroscience, rehabilitation medicine scientists have succeeded in developing functional electrical stimulation (FES) systems that enable certain individuals with SCI to use their paralyzed hands, arms, trunk, legs and diaphragm for functional purposes and gain a degree of control over bladder and bowel evacuation. This review presents an overview of the progress made, describes the current challenges and suggests ways to improve further FES systems and make these more widely available.

  13. Functional Electrical Stimulation in Spinal Cord Injury: Clinical Evidence Versus Daily Practice.

    Science.gov (United States)

    Bersch, Ines; Tesini, Stefani; Bersch, Ulf; Frotzler, Angela

    2015-10-01

    Functional electrical stimulation (FES) has clinical evidence in the rehabilitation of patients with spinal cord injury as indicated by several studies. Both inpatients and outpatients benefit from the therapeutic effect of the FES. The application areas are multifaceted and can be customized on the need for patients. This is represented by the individuality of the programmability of the stimulators and the variety of stimulation schedules that are based on the knowledge about the effects of FES on structural and functional level. Nevertheless, looking into daily clinical practice, the use of FES is rather poor. Expenditure of time, complexity of technical equipment, and compliance and acceptance of therapists and patients should be taken into account as limiting factors. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  14. Musculoskeletal adaptations in chronic spinal cord injury: effects of long-term soleus electrical stimulation training.

    Science.gov (United States)

    Shields, Richard K; Dudley-Javoroski, Shauna

    2007-01-01

    The purpose of this study was to determine whether long-term electrical stimulation training of the paralyzed soleus could change this muscle's physiological properties (torque, fatigue index, potentiation index, torque-time integral) and increase tibia bone mineral density. Four men with chronic (>2 years) complete spinal cord injury (SCI; American Spinal Injury Association classification A) trained 1 soleus muscle using an isometric plantar flexion electrical stimulation protocol. The untrained limb served as a within-subject control. The protocol involved ~ 30 minutes of training each day, 5 days a week, for a period of 6 to 11 months. Mean compliance over 11 months of training was 91% for 3 subjects. A fourth subject achieved high compliance after only 5 months of training. Mean estimated compressive loads delivered to the tibia were approximately 110% of body weight. Over the 11 months of training, the muscle plantar flexion torque, fatigue index, potentiation index, and torque-time integral were evaluated periodically. Bone mineral density (dual-energy x-ray absorptiometry) was evaluated before and after the training program. The trained limb fatigue index, potentiation index, and torque-time integral showed rapid and robust training effects (Pelectrical stimulation training yielded no changes to the proximal tibia bone mineral density, as measured by dual-energy x-ray absorptiometry. The subject with low compliance experienced fatigue index and torque-time integral improvements only when his compliance surpassed 80%. In contrast, his potentiation index showed adaptations even when compliance was low. These findings highlight the persistent adaptive capabilities of chronically paralyzed muscle but suggest that preventing musculoskeletal adaptations after SCI may be more effective than reversing changes in the chronic condition.

  15. Alterations in Localized Electrical Impedance Myography of Biceps Brachii Muscles Paralyzed by Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    Le Li

    2017-06-01

    Full Text Available This study assessed electrical impedance myography (EIM changes after spinal cord injury (SCI with a localized multifrequency technology. The EIM measurement was performed on the biceps brachii muscle at rest condition of 17 cervical SCI subjects, and 23 neurologically intact subjects as control group. The results showed that there was a significant decrease in muscle reactance (X and phase angle (θ at selected frequencies (i.e., 50 and 100 kHz in SCI compared to control. There was no significant difference in muscle resistance (R between the two groups. The anisotropy examination revealed that SCI group had a decreased anisotropy ratio in resistance. In addition, the multifrequency spectrum analysis showed a decreased slope of the log(freq-resistance regression in SCI group when compared to healthy control. Findings of the EIM changes are related to inherit muscle changes after the injury. Since EIM requires no patient effort and is quick and convenient to conduct, it may provide a useful tool for examination of paralyzed muscle changes after SCI.

  16. The views of people with spinal cord injury about the use of functional electrical stimulation.

    Science.gov (United States)

    Donovan-Hall, Maggie K; Burridge, Jane; Dibb, Bridget; Ellis-Hill, Caroline; Rushton, David

    2011-03-01

    Functional electrical stimulation (FES) is a specialist technique that can be applied in several areas of spinal rehabilitation. The aim of the study was to explore views of people with spinal cord injuries (SCI), health care professionals specializing in SCI, and researchers in FES about the current and future use of FES. A qualitative design using eight focus groups lasting 90 to 120 min was carried out throughout the UK. Purposive sampling was used to ensure diversity in age, level of SCI, severity of injury, and experience using FES. Thematic analysis identified five key themes. Decisions to use FES related to concerns over the screening and suitability of FES, ensuring parity between patients, and offering FES at the right stage of rehabilitation. Positive aspects of using FES related to themes regarding "physical improvements" and "doing something active." Barriers to using FES concerned a lack of resources, such as equipment and staff training, and the view that some FES devices were unreliable. This research highlights the importance of understanding the user's needs in the design of FES devices; improving provision, prescription and allocation of FES resources, and the need to consider psychosocial issues related to the initiation and use of FES. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  17. Electrical bioimpedance measurement during hypothermic rat kidney preservation for assessing ischemic injury.

    Science.gov (United States)

    Genescà, Meritxell; Ivorra, Antoni; Sola, Anna; Palacios, Luis; Goujon, Jean-Michel; Hauet, Thierry; Villa, Rosa; Aguiló, Jordi; Hotter, Georgina

    2005-03-15

    Non-heart-beating donors sustain an ischemic insult of unknown severity and duration, which can compromise the viability of the graft. This preliminary study aimed to assess whether electrical bioimpedance monitoring of cold preserved organs could be useful to identify kidneys that have suffered previous warm ischemia (WI). Two rat groups were studied during 24 h of preservation in University of Wisconsin solution (UW): a control cold ischemia group and another group subjected previously to 45 min of WI. Multi-frequency bioimpedance was monitored during preservation by means of a miniaturized silicon probe and the results were modeled according to the Cole equation. Tissular ATP content, lactate dehydrogenase in UW solution and histological injury were assessed. Renal function and cell injury, evaluated during 3 h of ex vivo reperfusion using the isolated perfused rat kidney model, demonstrated differences between groups. Bioimpedance results showed that the time constant and the high frequency resistivity parameters derived from the Cole equation were able to discriminate between groups at the beginning of the preservation (Deltatau approximately 78%, DeltaRinfinity approximately 36%), but these differences tended to converge as preservation time advanced. Nevertheless, another of the Cole parameters, alpha, showed increasing significant differences until 24 h of preservation (Deltaalpha approximately 15%).

  18. Effectiveness of electrical stimulation on rehabilitation after ligament and meniscal injuries: a systematic review

    Directory of Open Access Journals (Sweden)

    Aline Mizusaki Imoto

    Full Text Available CONTEXT AND OBJECTIVE: Electrical stimulation (ES is widely used to strengthen muscles following ligament and meniscal injuries. The aim of this study was to evaluate the effectiveness of ES for rehabilitation after soft tissue injuries of the knee treated surgically or conservatively. DESIGN AND SETTING: Systematic review at the Brazilian Cochrane Center. METHODS: We searched the Cochrane Central Register of Controlled Trials (2010, Issue 12, Medline (Medical Analysis and Retrieval System Online via PubMed (1966 to December 2010, Embase (Excerpta Medica database, 1980 to December 2010, Lilacs (Literatura Latino-Americana e do Caribe em Ciências da Saúde, 1982 to December 2010, and PEDro (Physiotherapy Evidence Database, 1929 to December 2010. The studies included were randomized controlled trials using ES to increase muscle strength for rehabilitation of patients with soft tissue injuries of the knee. Two authors independently evaluated studies for inclusion and performed data extraction and methodological quality assessment. RESULTS: Seventeen studies evaluating ES after anterior cruciate ligament reconstruction and two studies evaluating ES after meniscectomy were included. There was a statistically significant improvement in quadriceps strength through ES (mean difference, MD: -32.7; 95% confidence interval, CI: -39.92 to -25.48; n = 56 and in functional outcomes (MD -7; -12.78 to -1.22; n = 43 six to eight weeks after surgical reconstruction of the anterior cruciate ligament. CONCLUSION: There is evidence that ES coupled with conventional rehabilitation exercises may be effective in improving muscle strength and function two months after surgery

  19. Electrical Structure of Future Off-shore Wind Power Plant with a High Voltage Direct Current Power Transmission

    OpenAIRE

    Sharma, Ranjan; Andersen, Michael A. E.; Akhmatov, Vladislav; Jensen, Kim Høj; Rasmussen, Tonny Wederberg

    2012-01-01

    The increasing demand of electric power and the growing consciousness towards the changing climate has led to a rapid development of renewable energy in the recent years. Among all, wind energy has been the fastest growing energy source in the last decade. But the growing size of wind power plants, better wind conditions at off-shore and the general demand to put them out of sight have all contributed to the installation of large wind power plants in off-shore condition. However, moving wind ...

  20. Effects of modified electrical stimulation-induced leg cycle ergometer training for individuals with spinal cord injury

    NARCIS (Netherlands)

    Janssen, T.W.J.; Pringle, D.D.

    2008-01-01

    Computer-controlled electrical stimulation (ES)-induced leg cycle ergometer (ES-LCE) exercise can be beneficial for individuals with spinal cord injury (SCI), but exercise performance is often insufficient for eliciting continuous gains in cardiopulmonary training adaptations. The first purpose of

  1. Combining the single-walled carbon nanotubes with low voltage electrical stimulation to improve accumulation of nanomedicines in tumor for effective cancer therapy.

    Science.gov (United States)

    Lee, Pei-Chi; Peng, Cheng-Liang; Shieh, Ming-Jium

    2016-03-10

    Effective delivery of biomolecules or functional nanoparticles into target sites has always been the primary objective for cancer therapy. We demonstrated that by combining single-walled carbon nanotubes (SWNTs) with low-voltage (LV) electrical stimulation, biomolecule delivery can be effectively enhanced through reversible electroporation (EP). Clear pore formation in the cell membrane is observed due to LV (50V) pulse electrical stimulation amplified by SWNTs. The cell morphology remains intact and high cell viability is retained. This modality of SWNT + LV pulses can effectively transfer both small molecules and macromolecules into cells through reversible EP. The results of animal studies also suggest that treatment with LV pulses alone cannot increase vascular permeability in tumors unless after the injection of SWNTs. The nanoparticles can cross the permeable vasculature, which enhances their accumulation in the tumor tissue. Therefore, in cancer treatment, both SWNT + LV pulse treatment followed by the injection of LIPO-DOX® and SWNT/DOX + LV pulse treatment can increase tumor inhibition and delay tumor growth. This novel treatment modality applied in a human cancer xenograft model can provide a safe and effective therapy using various nanomedicines in cancer treatment. Copyright © 2016. Published by Elsevier B.V.

  2. The effects of electrical stunning voltage on meat quality, plasma parameters, and protein solubility of broiler breast meat.

    Science.gov (United States)

    Huang, J C; Yang, J; Huang, M; Chen, K J; Xu, X L; Zhou, G H

    2017-03-01

    This study was designed to compare the effects of different stunning voltages of pulsed direct current on meat quality of broilers. For this purpose, plasma parameters, blood loss, carcass damage, and meat water holding capacity, color, shear force, pH, and protein solubility were analyzed. A total of 400 broilers were divided into 5 treatment groups and stunned with 5, 15, 25, 35, and 45 V at 750 Hz and 10 s, respectively. Blood samples were collected immediately after cutting the neck. Pectoralis major muscles were removed from the carcass after chilling and placed on ice. Breast muscle pH and meat color were determined at both 2 and 24 h postmortem. Dripping loss, cooking loss, pressing loss, and cooked breast meat shear values were determined after 24 h postmortem. The 5 V treatment significantly increased (P < 0.05) blood plasma corticosterone and lactate concentration compared with the other groups. The carcass damage of wings, Pectoralis major, and Pectoralis minor was significant in the 5, 35, and 45 V groups. The pH of 2 h postmortem in the 5 and 45 V groups was significantly lower (P < 0.05) than in the 15 and 25 V groups. In the 5 and 45 V groups, the protein solubility and shear force value were significantly lower (P < 0.05) and dripping loss was significantly higher (P < 0.05) than the other groups. © 2016 Poultry Science Association Inc.

  3. The Effect of Electrical Passive Cycling on Spasticity in War Veterans with Spinal Cord Injury

    Science.gov (United States)

    Rayegani, Seyed Mansoor; Shojaee, Hadi; Sedighipour, Leyla; Soroush, Mohammad Reza; Baghbani, Mohammad; Amirani, Omm’ol Banin

    2011-01-01

    Introduction: Muscle atrophy, spasticity, and deformity are among long term complication of spinal cord injury (SCI) veterans. There are numerous studies evaluating effect of functional electrical stimulation on muscle properties of SCI people, but less research has focused on the benefits of passive cycling in the management of spasticity and improving ROM of lower limbs in individuals with SCI. Aims: To evaluate the effect of electrical passive cycling on passive range of movement spasticity and electrodiagnostic parameters in SCI veterans. Methods: Sixty-four SCI veterans referred to two clinical and research center in Tehran were recruited in this prospective clinical trial. The subjects were divided into two groups according to electrical passive cycling usage: (1) patients who did not use pedal exercise (control group), (2) patients used Electrical passive cycling up to optimal level (intervention group). Main outcome measures included hip, knee, and ankle range of motion, spasticity scale, and electrodiagnostic parameters including F-Wave Consistency, F-Wave Amplitude, H/M Ratio, F/M Ratio, H-Reflex Onset Latency, and H-Reflex Amplitude. Data were recorded at the time of receiving and 1 year after pedal exercise usage. Results: Sixty-four SCI patients including 95.3% male, 4.7% female with mean age 43 years old were included in this study. All patients except one suffered from complete SCI. The involved spinal levels were cervical (17.2%), upper thoracic (34.4%), lower thoracic (45.3%), and lumbar (3.1%). Spasticity scale decreased significantly after passive cycling in group 2. Also hip, knee, and ankle ROM in group 2 were significantly improved after pedal exercise. There was a significant difference in H max/M max (RT<) and F/M ratio after versus before electric passive cycling system in group 2. Conclusion: These findings suggest that passive rhythmic leg exercise can lead to decrease in spasticity, increase in passive ROM of lower limbs and

  4. Posterolateral surface electrical stimulation of abdominal expiratory muscles to enhance cough in spinal cord injury.

    Science.gov (United States)

    Butler, Jane E; Lim, Julianne; Gorman, Robert B; Boswell-Ruys, Claire; Saboisky, Julian P; Lee, Bonsan B; Gandevia, Simon C

    2011-02-01

    Spinal cord injury (SCI) patients have respiratory complications because of abdominal muscle weakness and paralysis, which impair the ability to cough. This study aims to enhance cough in high-level SCI subjects (n = 11, SCI at or above T6) using surface electrical stimulation of the abdominal muscles via 2 pairs of posterolaterally placed electrodes. From total lung capacity, subjects performed maximum expiratory pressure (MEP) efforts against a closed airway and voluntary cough efforts. Both efforts were performed with and without superimposed trains of electrical stimulation (50 Hz, 1 second) at a submaximal intensity set to evoke a gastric pressure (P(ga)) of 40 cm H(2)O at functional residual capacity. In the MEP effort, stimulation increased the maximal P(ga) (from 21.4 ± 7.0 to 59.0 ± 5.7 cm H(2)O) and esophageal pressure (P(es); 47.2 ± 11.7 to 65.6 ± 13.6 cm H(2)O). During the cough efforts, stimulation increased P(ga) (19.5 ± 6.0 to 57.9 ± 7.0 cm H(2)O) and P(es) (31.2 ± 8.7 to 56.6 ± 10.5 cm H(2)O). The increased expiratory pressures during cough efforts with stimulation increased peak expiratory flow (PEF, by 36% ± 5%), mean expiratory flow (by 80% ± 8%), and expired lung volume (by 41% ± 16%). In every subject, superimposed electrical stimulation improved peak expiratory flow during cough efforts (by 0.99 ± 0.12 L/s; range, 0.41-1.80 L/s). Wearing an abdominal binder did not improve stimulated cough flows or pressures. The increases in P(ga) and PEF with electrical stimulation using the novel posterolateral electrode placement are 2 to 3 times greater than improvements reported in other studies. This suggests that posterolateral electrical stimulation of abdominal muscles is a simple noninvasive way to enhance cough in individuals with SCI.

  5. The effect of electrical passive cycling on spasticity in war veterans with SCI (Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    Seyed M Rayegani

    2011-06-01

    Full Text Available Introduction: Muscle atrophy, spasticity and deformity are among long term complication of Spinal Cord Injury(SCI veterans. There are numerous studies evaluating effect of functional electrical stimulation (FES on muscle properties of SCI people, but less research has focused on the benefits of passive cycling in the management of spasm and improving ROM of lower limbs in individuals with SCI. Aims: To evaluate the effect of electrical passive cycling on passive range of movement spasticity and electrodiagnostic parameters in SCI veterans. Methods: 64 SCI veterans referred to two clinical and research center in Tehran were recruited in this prospective clinical trial. The subjects were divided into 2 groups according to electrical passive cycling usage: 1 patients who didn’t use pedal exercise(control group, 2 patients used Electrical passive cycling up to optimal level (intervention group . Main outcome measures included hip, knee and ankle rang of motion, spacticity scale, and electrodiagnostic parameters including F-Wave Consistency, F-Wave Amplitude, H/M Ratio, F/M Ratio, H Reflex Onset Latency and H Reflex Amplitude. Data were recorded at the time of receiving and one year after pedal exercise usage. Results : Sixty four SCI patients including 95.3% male, 4.7% female with mean age 43 years old were included in this study. All patients except one had complete SCI suffered from complete SCI. The involved spinal levels were cervical(17.2%, upper thoracic (34.4%, lower thoracic (45.3% and lumbar (3.1%. Spasticity scale decreased significantly after passive cycling in group 2 and 3. Also hip, knee and ankle ROM in group 2 and 3 were significantly improved after pedal exercise. There was a significant difference in H max/M max (RT< and F/M ratio after versus before electric passive cycling system in group 2. Conclusion: These findings suggest that passive rythmic leg exercise can lead to decrease in spasticity ,increase in passive ROM of low

  6. The effect of electrical passive cycling on spasticity in war veterans with spinal cord injury.

    Science.gov (United States)

    Rayegani, Seyed Mansoor; Shojaee, Hadi; Sedighipour, Leyla; Soroush, Mohammad Reza; Baghbani, Mohammad; Amirani, Omm'ol Banin

    2011-01-01

    Muscle atrophy, spasticity, and deformity are among long term complication of spinal cord injury (SCI) veterans. There are numerous studies evaluating effect of functional electrical stimulation on muscle properties of SCI people, but less research has focused on the benefits of passive cycling in the management of spasticity and improving ROM of lower limbs in individuals with SCI. To evaluate the effect of electrical passive cycling on passive range of movement spasticity and electrodiagnostic parameters in SCI veterans. Sixty-four SCI veterans referred to two clinical and research center in Tehran were recruited in this prospective clinical trial. The subjects were divided into two groups according to electrical passive cycling usage: (1) patients who did not use pedal exercise (control group), (2) patients used Electrical passive cycling up to optimal level (intervention group). Main outcome measures included hip, knee, and ankle range of motion, spasticity scale, and electrodiagnostic parameters including F-Wave Consistency, F-Wave Amplitude, H/M Ratio, F/M Ratio, H-Reflex Onset Latency, and H-Reflex Amplitude. Data were recorded at the time of receiving and 1 year after pedal exercise usage. Sixty-four SCI patients including 95.3% male, 4.7% female with mean age 43 years old were included in this study. All patients except one suffered from complete SCI. The involved spinal levels were cervical (17.2%), upper thoracic (34.4%), lower thoracic (45.3%), and lumbar (3.1%). Spasticity scale decreased significantly after passive cycling in group 2. Also hip, knee, and ankle ROM in group 2 were significantly improved after pedal exercise. There was a significant difference in H max/M max (RT<) and F/M ratio after versus before electric passive cycling system in group 2. These findings suggest that passive rhythmic leg exercise can lead to decrease in spasticity, increase in passive ROM of lower limbs and improvement in electrodiagnostic parameters of

  7. Semiconditional electrical stimulation of pudendal nerve afferents stimulation to manage neurogenic detrusor overactivity in patients with spinal cord injury.

    Science.gov (United States)

    Lee, Young-Hee; Kim, Jung Moon; Im, Hyung Tae; Lee, Kye-Wook; Kim, Sung Hoon; Hur, Dong Min

    2011-10-01

    To evaluate the effect of semiconditional electrical stimulation of the pudendal nerve afferents for the neurogenic detrusor overactivity in patients with spinal cord injury. Forty patients (36 males, 4 males) with spinal cord injury who had urinary incontinence and frequency, as well as felt bladder contraction with bladder filling sense or autonomic dysreflexic symptom participated in this study. Patients with neurogenic detrusor overactivity were subdivided into complete injury and incomplete injury groups by ASIA classification and subdivided into tetraplegia and paraplegia groups by neurologic level of injury. Bladder function, such as bladder volumes infused to the bladder until the first occurrence of neurogenic detrusor overactivity (V(ini)) and the last contraction suppressed by electrical stimulation (V(max)) was measured by water cystometry (CMG) and compared with the results of each subgroup. Among the 40 subjects, 35 patients showed neurogenic detrusor overactivity in the CMG study. Among these 35 patients, detrusor overactivity was suppressed effectively by pudendal nerve afferent electrical stimulation in 32 patients. The infusion volume until the occurrence of the first reflex contraction (V(ini)) was 99.4±80.3 ml. The volume of saline infused to the bladder until the last contraction suppressed by semiconditional pudendal nerve stimulation (V(max)) was 274.3±93.2 ml, which was significantly greater than V(ini). In patients with good response to the pudendal nerve afferent stimulation, the bladder volume significantly increased by stimulation in all the patients. In this study, semiconditional electrical stimulation on the dorsal penile afferent nerve could effectively inhibit neurogenic detrusor overactivity and increase bladder volume in patients with spinal cord injury.

  8. Electrical stimulation of abdominal muscles to produce cough in spinal cord injury: effect of stimulus intensity.

    Science.gov (United States)

    McBain, Rachel A; Boswell-Ruys, Claire L; Lee, Bonsan B; Gandevia, Simon C; Butler, Jane E

    2015-05-01

    Surface electrical stimulation of the abdominal muscles, with electrodes placed in the posterolateral position, combined with a voluntary cough can assist clearance of airway secretions in individuals with high-level spinal cord injury (SCI). To determine whether an increase in stimulus intensity of the trains of electrical stimuli delivered to the expiratory muscles has an increasing effect on a stimulated voluntary cough and to determine at which stimulus intensity a plateau of cough peak expiratory flow occurs. In 7 healthy individuals with a SCI at and above C7, gastric pressure (P(ga)), esophageal pressure (P(es)), peak expiratory cough flow (PEF(cough)), and expiratory volume were measured as participants coughed voluntarily with simultaneous trains of electrical stimuli delivered over the abdominal muscles (50 Hz, 1-s duration). The intensity of the stimulation was increased incrementally. A plateau in PEF(cough) occurred in all 7 individuals at a mean of 211 ± 29 mA (range 120-360 mA). Peak values reached for P(ga), P(es), and PEF(cough) were 83.0 ± 8.0 cm H2O, 66.1 ± 5.6 cm H2O, and 4.0 ± 0.4 l/s respectively. The plateau in expiratory cough flow that was associated with increasing expiratory pressures is indicative of dynamic airway compression. This suggests that the evoked cough will be effective in creating more turbulent airflow to further assist in dislodging mucus and secretions. © The Author(s) 2014.

  9. Electrical muscle stimulation elevates intramuscular BDNF and GDNF mRNA following peripheral nerve injury and repair in rats.

    Science.gov (United States)

    Willand, Michael P; Rosa, Elyse; Michalski, Bernadeta; Zhang, Jennifer J; Gordon, Tessa; Fahnestock, Margaret; Borschel, Gregory H

    2016-10-15

    Despite advances in surgery, patients with nerve injuries frequently have functional deficits. We previously demonstrated in a rat model that daily electrical muscle stimulation (EMS) following peripheral nerve injury and repair enhances reinnervation, detectable as early as two weeks post-injury. In this study, we explain the enhanced early reinnervation observed with electrical stimulation. In two groups of rats, the tibial nerve was transected and immediately repaired. Gastrocnemius muscles were implanted with intramuscular electrodes for sham or muscle stimulation. Muscles were stimulated daily, eliciting 600 contractions for one hour/day, repeated five days per week. Sixteen days following nerve injury, muscles were assessed for functional reinnervation by motor unit number estimation methods using electromyographic recording. In a separate cohort of rats, surgical and electrical stimulation procedures were identical but muscles and distal nerve stumps were harvested for molecular analysis. We observed that stimulated muscles had significantly higher motor unit number counts. Intramuscular levels of brain-derived and glial cell line-derived neurotrophic factor (BDNF and GDNF) mRNA were significantly upregulated in muscles that underwent daily electrical stimulation compared to those without stimulation. The corresponding levels of trophic factor mRNA within the distal stump were not different from one another, indicating that the intramuscular electrical stimulus does not modulate Schwann cell-derived trophic factor transcription. Stimulation over a three-month period maintained elevated muscle-derived GDNF but not BDNF mRNA. In conclusion, EMS elevates intramuscular trophic factor mRNA levels which may explain how EMS enhances neural regeneration following nerve injury. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. Electrical flash burns due to switchboard explosions in New South Wales--a 9-year experience.

    Science.gov (United States)

    Aggarwal, Shagun; Maitz, Peter; Kennedy, Peter

    2011-09-01

    To document the incidence and outcome of flash burns due to electrical switchboard explosions presenting to Concord Hospital Burns Unit, from January 2000 to December 2008. The Concord Hospital Burns Unit Database was reviewed for admissions due to electrical burns from January 2000 to December 2008. There were 119 electrical burns admitted during the study period, 20 of which were due to high voltage current. Ninety-nine others were low voltage injuries and included 37 cases of electrical burns due to low voltage electrical switchboard explosions. All of the electrical switchboard burns occurred in male electricians. Twenty-one of the 37 low voltage injuries required admission and 7 of them required skin grafting. The mean LOS was 9.95 days. Twenty cases suffered serious complications including major psychological problems and ocular injuries. Flash burns resulting from switchboard explosions account for a significant proportion of all electrical burns presenting to our institution. These burns may highlight deficits in taking safety precautions and the use of personal protection equipment. Despite the small area of injury the long term psychological sequelae were significant resulting in a delayed return to employment, and there was a high incidence of eye injuries. Additional efforts are therefore required towards the prevention of such injuries. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

  11. Conceptual model of a logical system processor of selection to electrical filters for correction of harmonics in low voltage lines

    Science.gov (United States)

    Lastre, Arlys; Torriente, Ives; Méndez, Erik F.; Cordovés, Alexis

    2017-06-01

    In the present investigation, the authors propose a conceptual model for the analysis and the decision making of the corrective models to use in the mitigation of the harmonic distortion. The authors considered the setting of conventional models, and such adaptive models like the filters incorporation to networks neuronal artificial (RNA's) for the mitigating effect. In addition to the present work is a showing of the experimental model that learns by means of a flowchart denoting the need to use artificial intelligence skills for the exposition of the proposed model. The other aspect considered and analyzed are the adaptability and usage of the same, considering a local reference of the laws and lineaments of energy quality that demands the Department of Electricity and Energy Renewable (MEER) of Equator.

  12. Voltage-Gated Na+ Channel Isoforms and Their mRNA Expression Levels and Protein Abundance in Three Electric Organs and the Skeletal Muscle of the Electric Eel Electrophorus electricus.

    Directory of Open Access Journals (Sweden)

    Biyun Ching

    Full Text Available This study aimed to obtain the coding cDNA sequences of voltage-gated Na+ channel (scn α-subunit (scna and β-subunit (scnb isoforms from, and to quantify their transcript levels in, the main electric organ (EO, Hunter's EO, Sach's EO and the skeletal muscle (SM of the electric eel, Electrophorus electricus, which can generate both high and low voltage electric organ discharges (EODs. The full coding sequences of two scna (scn4aa and scn4ab and three scnb (scn1b, scn2b and scn4b were identified for the first time (except scn4aa in E. electricus. In adult fish, the scn4aa transcript level was the highest in the main EO and the lowest in the Sach's EO, indicating that it might play an important role in generating high voltage EODs. For scn4ab/Scn4ab, the transcript and protein levels were unexpectedly high in the EOs, with expression levels in the main EO and the Hunter's EO comparable to those of scn4aa. As the key domains affecting the properties of the channel were mostly conserved between Scn4aa and Scn4ab, Scn4ab might play a role in electrogenesis. Concerning scnb, the transcript level of scn4b was much higher than those of scn1b and scn2b in the EOs and the SM. While the transcript level of scn4b was the highest in the main EO, protein abundance of Scn4b was the highest in the SM. Taken together, it is unlikely that Scna could function independently to generate EODs in the EOs as previously suggested. It is probable that different combinations of Scn4aa/Scn4ab and various Scnb isoforms in the three EOs account for the differences in EODs produced in E. electricus. In general, the transcript levels of various scn isoforms in the EOs and the SM were much higher in adult than in juvenile, and the three EOs of the juvenile fish could be functionally indistinct.

  13. Recycling ``in situ`` of dielectric oil of electric transformer of medium and high voltage; Reciclaje ``in situ`` y ``en carga`` del aceite dielectrico de los transformadores electricos de media y alta tension

    Energy Technology Data Exchange (ETDEWEB)

    Solis, A.

    1997-06-01

    The author describes the process followed by the company to control the quality of every type of oil from electric transformer of medium and high voltage polluted because of its use. The pollutants contained in the dielectric liquid are eliminated or minimize through the following treatments: conditioning-reconditioning-regeneration. (Author) 6 refs.

  14. Research of equipment possession and gas and electric power habits of commercial and industrial consumers of low voltage; Pesquisa de posse de equipamentos e habitos de consumo de energia eletrica e gas de consumidores comerciais e industriais em baixa tensao

    Energy Technology Data Exchange (ETDEWEB)

    Jardini, Jose Antonio; Casolari, Ronaldo Pedro; Angrisano, Alexandre; Araujo, Dalva Souza de [Universidade de Sao Paulo, SP (Brazil). Escola Politecnica

    2000-07-01

    This paper reports a survey conducted by the Departamento de Energia e Automacao Eletrica, Escola Politecnica da Universidade de Sao Paulo, on the possession of electric and gas equipment, and the habits of consumption which were applied to a consumers attended in low voltage commercial class and industrial class services, in the state of Sao Paulo, Brazil.

  15. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics Individualized Learning System. CANTRAC A-100-0010. Module Nine: Relationships of Current, Counter EMF, and Voltage in LR Circuits. Study Booklet.

    Science.gov (United States)

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on the relationships of current, electromotive force, and voltage in inductive-resistive circuits is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and…

  16. Electric Substations

    Data.gov (United States)

    Department of Homeland Security — Substations. Substations are facilities and equipment that switch, transform, or regulate electric voltage. The Substations feature class includes taps, a location...

  17. TNF-α enhances the currents of voltage gated sodium channels in uninjured dorsal root ganglion neurons following motor nerve injury.

    Science.gov (United States)

    Chen, Xi; Pang, Rui-Ping; Shen, Kai-Feng; Zimmermann, Manfred; Xin, Wen-Jun; Li, Yong-Yong; Liu, Xian-Guo

    2011-02-01

    The ectopic discharges observed in uninjured dorsal root ganglion (DRG) neurons following various lesions of spinal nerves have been attributed to functional alterations of voltage-gated sodium channels (VGSCs). Such mechanisms may be important for the development of neuropathic pain. However, the pathophysiology underlying the functional modulation of VGSCs following nerve injury is largely unknown. Here, we studied this issue with use of a selective lumbar 5 ventral root transection (L5-VRT) model, in which dorsal root ganglion (DRG) neurons remain intact. We found that the L5-VRT increased the current densities of TTX-sensitive Na channels as well as currents in Nav1.8, but not Nav1.9 channels in uninjured DRG neurons. The thresholds of action potentials decreased and firing rates increased in DRG neurons following L5-VRT. As we found that levels of tumor necrosis factor-alpha (TNF-α) increased in cerebrospinal fluid (CSF) and in DRG tissue after L5-VRT, we tested whether the increased TNF-α might result in the changes in sodium channels. Indeed, recombinant rat TNF (rrTNF) enhanced the current densities of TTX-S and Nav1.8 in cultured DRG neurons dose-dependently. Furthermore, genetic deletion of TNF receptor 1 (TNFR-1) in mice attenuated the mechanical allodynia and prevented the increase in sodium currents in DRG neurons induced by L5-VRT. These data suggest that the increase in sodium currents in uninjured DRG neurons following nerve injury might be mediated by over-production of TNF-α. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. APPROXIMATE CALCULATION OF ACTIVE RESISTANCE AND TEMPERATURE OF THE PULSE ELECTRIC ARC CHANNEL IN A HIGH-CURRENT DISCHARGE CIRCUIT OF A POWERFUL HIGH-VOLTAGE CAPACITOR ENERGY STORAGE

    Directory of Open Access Journals (Sweden)

    M.I. Baranov

    2017-08-01

    Full Text Available Purpose. To obtain calculation correlations for active resistance Rce and maximal temperature Tme of plasma channel of pulse electric arc in the air double-electrode system (DES with metal (graphite electrodes, and also practical approbation of the obtained correlations for Rce and Tme in the conditions of high-voltage laboratory on the powerful capacity energy storage (CES of electric setting, intended for reproducing on the electric loading of protracted C- component of current of artificial lightning with the USA rationed on normative documents by amplitude-temporal parameters (ATP. Methodology. Electrophysics bases of high-voltage impulse technique, scientific and technical bases of development and creation of high-voltage high-current impulse electrical equipment, including powerful CES, and also measuring methods in discharge circuits of powerful high-voltage CES of pulse currents of millisecond temporal range. Results. On the basis of engineering approach the new results of approximate calculation of values of Rce and Tme are resulted in the plasma channel of pulse electric arc discharge in air DES of atmospheric pressure with metallic (graphite electrodes. Practical approbation of results of calculation of values of Rce and Tme is executed as it applies to air DES, to connected in a discharge circuit of powerful high-voltage CES with protracted C- of component current of artificial lightning, characterized rationed ATP. It is shown that calculation of numeral value Rce approximately in 100 times exceeds the proper value of active resistance for the plasma channel of impulsive spark of electric discharge in air DES other things being equal, and a calculation of numeral value Tme well corresponds with the known thermodynamics information for classic electric arc in air DES of atmospheric pressure with graphite electrodes. Originality. New engineering approach is developed for the approximate calculation of values of Rce and Tme in electron

  19. Electrical stimulation accelerates nerve regeneration and functional recovery in delayed peripheral nerve injury in rats.

    Science.gov (United States)

    Huang, Jinghui; Zhang, Yongguang; Lu, Lei; Hu, Xueyu; Luo, Zhuojing

    2013-12-01

    The present study aims to investigate the potential of brief electrical stimulation (ES; 3 V, 20 Hz, 20 min) in improving functional recovery in delayed nerve injury repair (DNIR). The sciatic nerve of Sprague Dawley rats was transected, and the repair of nerve injury was delayed for different time durations (2, 4, 12 and 24 weeks). Brief depolarizing ES was applied to the proximal nerve stump when the transected nerve stumps were bridged with a hollow nerve conduit (5 mm in length) after delayed periods. We found that the diameter and number of regenerated axons, the thickness of myelin sheath, as well as the number of Fluoro-Gold retrograde-labeled motoneurons and sensory neurons were significantly increased by ES, suggesting that brief ES to proximal nerve stumps is capable of promoting nerve regeneration in DNIR with different delayed durations, with the longest duration of 24 weeks. In addition, the amplitude of compound muscle action potential (gastrocnemius muscle) and nerve conduction velocity were also enhanced, and gastrocnemius muscle atrophy was partially reversed by brief ES, indicating that brief ES to proximal nerve stump was able to improve functional recovery in DNIR. Furthermore, brief ES was capable of increasing brain-derived neurotrophic factor (BDNF) expression in the spinal cord in DNIR, suggesting that BDNF-mediated neurotrophin signaling might be one of the contributing factors to the beneficial effect of brief ES on DNIR. In conclusion, the present findings indicate the potential of using brief ES as a useful method to improve functional recovery for delayed repair of peripheral nerve lesions. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  20. Screening and habituation of functional electrical stimulation-leg cycle ergometry for individuals with spinal cord injury: a pilot study.

    Science.gov (United States)

    Tawashy, Amira E; Eng, Janice J; Krassioukov, Andrei V; Warburton, Darren E R; Ashe, Maureen C; Hung, Chihya

    2008-12-01

    To document the screening process and develop the habituation procedures prior to commencing a functional electrical stimulation leg cycle ergometry (FES-LCE) exercise program for individuals with spinal cord injury (SCI). This was a prospective descriptive study of screening and habituation for FES-LCE exercise for people with chronic SCI (injury duration longer than one year). : Tertiary rehabilitation center. Thirteen subjects with SCI (mean years since injury, 7; mean age, 34.8 years; injury range, C4-T10; 7 males). Time to attain target cycle speed for 30 continuous minutes. Six of the 13 subjects were not eligible to start the FES-LCE habituation program because of previous fragility fracture, excessive spasticity, pain, autonomic dysreflexia, or lack of electrical stimulation response because of lower motor neuron damage in individuals with low thoracic injuries (T11-12). Time to attain target cycle speed for 30 continuous minutes ranged from 30 to 779 minutes (1-31 training sessions). Almost half of the individuals interested in participating in the FES-LCE exercise program did not pass the screening phase. Although the habituation phase was time-consuming for most of the participants who were able to use the FES-LCE, all reported few adverse effects to using the device once they completed this phase of training.

  1. Musculoskeletal plasticity after acute spinal cord injury: effects of long-term neuromuscular electrical stimulation training.

    Science.gov (United States)

    Shields, Richard K; Dudley-Javoroski, Shauna

    2006-04-01

    Maintaining the physiologic integrity of paralyzed limbs may be critical for those with spinal cord injury (SCI) to be viable candidates for a future cure. No long-term intervention has been tested to attempt to prevent the severe musculoskeletal deterioration that occurs after SCI. The purposes of this study were to determine whether a long-term neuromuscular electrical stimulation training program can preserve the physiological properties of the plantar flexor muscles (peak torque, fatigue index, torque-time integral, and contractile speed) as well as influence distal tibia trabecular bone mineral density (BMD). Subjects began unilateral plantar flexion electrical stimulation training within 6 wk after SCI while the untrained leg served as a control. Mean compliance for the 2-yr training program was 83%. Mean estimated compressive loads delivered to the tibia were approximately 1-1.5 times body weight. The training protocol yielded significant trained versus untrained limb differences for torque (+24%), torque-time integral (+27%), fatigue index (+50%), torque rise time (+45%), and between-twitch fusion (+15%). These between-limb differences were even greater when measured at the end of a repetitive stimulation protocol (125 contractions). Peripheral quantitative computed tomography revealed 31% higher distal tibia trabecular BMD in trained limbs than in untrained limbs. The intervention used in this study was sufficient to limit many of the deleterious muscular and skeletal adaptations that normally occur after SCI. Importantly, this method of load delivery was feasible and may serve as the basis for an intervention to preserve the musculoskeletal properties of individuals with SCI.

  2. Strength and endurance adaptations to functional electrical stimulation leg cycle ergometry in spinal cord injury.

    Science.gov (United States)

    Thrasher, Timothy Adam; Ward, John Stanley; Fisher, Stanley

    2013-01-01

    To describe adaptations in power output, quadriceps muscle strength, and fatigability that occur during a 13-week regimen of Functional Electrical Stimulation Leg Cycle Ergometry (FES-LCE) in Spinal Cord Injury (SCI). To identify differences in outcomes between individuals with complete and incomplete motor impairment. Observational and longitudinal. Rehabilitation and biomechanics research laboratory. Eleven (N = 11) individuals with SCI and no previous FES-LCE experience. 40 sessions of FES-LCE at a rate of three sessions per week. Continuous exercise was performed at a pedal cadence of 45 RPM against a constant resistance for up to 60 minutes. Mean power output was recorded for each session. Before and after the training regimen, each subject performed a fatigue test in which electrically stimulated knee extension torque and Fatigue Index were measured. Participants demonstrated significant increases in mean power output (9.0 to 20.3 W; p < 0.001), peak isometric knee extension torque (3.8 to 16.9 Nm; p = 0.006) and sustainable isometric knee extension torque (4.9 to 14.4 Nm; p = 0.001) after FES-LCE training (95% confidence intervals). Participants with incomplete motor impairment demonstrated a decrease in Fatigue Index (p = 0.021), and improved mean power output more than those with complete motor impairment (p = 0.037). Significant improvements in muscle conditioning and exercise performance are possible following the 13-week regimen of FES-LCE described in this article. Individuals with incomplete motor impairment experience greater improvements in mean power output than individuals with complete motor impairment.

  3. Low Wind Speed Turbine Project Phase II: The Application of Medium-Voltage Electrical Apparatus to the Class of Variable Speed Multi-Megawatt Low Wind Speed Turbines; 15 June 2004--30 April 2005

    Energy Technology Data Exchange (ETDEWEB)

    Erdman, W.; Behnke, M.

    2005-11-01

    Kilowatt ratings of modern wind turbines have progressed rapidly from 50 kW to 1,800 kW over the past 25 years, with 3.0- to 7.5-MW turbines expected in the next 5 years. The premise of this study is simple: The rapid growth of wind turbine power ratings and the corresponding growth in turbine electrical generation systems and associated controls are quickly making low-voltage (LV) electrical design approaches cost-ineffective. This report provides design detail and compares the cost of energy (COE) between commercial LV-class wind power machines and emerging medium-voltage (MV)-class multi-megawatt wind technology. The key finding is that a 2.5% reduction in the COE can be achieved by moving from LV to MV systems. This is a conservative estimate, with a 3% to 3.5% reduction believed to be attainable once purchase orders to support a 250-turbine/year production level are placed. This evaluation considers capital costs as well as installation, maintenance, and training requirements for wind turbine maintenance personnel. Subsystems investigated include the generator, pendant cables, variable-speed converter, and padmount transformer with switchgear. Both current-source and voltage-source converter/inverter MV topologies are compared against their low-voltage, voltage-source counterparts at the 3.0-, 5.0-, and 7.5-MW levels.

  4. Cardiovascular response of individuals with spinal cord injury to dynamic functional electrical stimulation under orthostatic stress.

    Science.gov (United States)

    Yoshida, Takashi; Masani, Kei; Sayenko, Dimitry G; Miyatani, Masae; Fisher, Joseph A; Popovic, Milos R

    2013-01-01

    In this pilot study, we examined how effectively functional electrical stimulation (FES) and passive stepping mitigated orthostatic hypotension in participants with chronic spinal cord injury (SCI). While being tilted head-up to 70 (°) from the supine position, the participants underwent four 10-min conditions in a random sequence: 1) no intervention, 2) passive stepping, 3) isometric FES of leg muscles, and 4) FES of leg muscles combined with passive stepping. We found that FES and passive stepping independently mitigated a decrease in stroke volume and helped to maintain the mean blood pressure. The effects of FES on stroke volume and mean blood pressure were greater than those of passive stepping. When combined, FES and passive stepping did not interfere with each other, but they also did not synergistically increase stroke volume or mean blood pressure. Thus, the present study suggests that FES delivered to lower limbs can be used in individuals with SCI to help them withstand orthostatic stress. Additional studies are needed to confirm whether this use of FES is applicable to a larger population of individuals with SCI.

  5. Functional electrical stimulation therapy for grasping in traumatic incomplete spinal cord injury: randomized control trial.

    Science.gov (United States)

    Kapadia, Naaz M; Zivanovic, Vera; Furlan, Julio C; Craven, B Cathy; McGillivray, Colleen; Popovic, Milos R

    2011-03-01

    The purpose of this single-site randomized control trial was to assess the short-term and long-term efficacy of functional electrical stimulation (FES) therapy over conventional occupational therapy in improving voluntary hand function in incomplete C4-C7 spinal cord injury individuals. All 22 participants recruited in this randomized control trial received treatment for both the left and right upper extremities. Every participant, irrespective of group allocation, received one dose (60 min per day, 5 days per week for the duration of 8 weeks) of conventional occupational therapy for hand function. Of the 22 participants, 12 individuals received an additional dose of conventional occupational therapy, while the remaining 10 participants received a dose of FES hand therapy. The primary outcome measure was Functional Independence Measure (FIM) self-care subscore. The secondary outcome measures were Spinal Cord Independence Measure (SCIM) self-care subscore and Toronto Rehabilitation Institute Hand Function Test (TRI-HFT). The participants who received FES therapy showed significantly greater improvements in hand function at discharge, and were able to maintain their gains at long-term follow-up as assessed using FIM self-care subscore, SCIM self-care subscore, and TRI-HFT. The FES therapy effectively increased independence and thereby improved quality of life of individuals with tetraplegia when compared with conventional occupational therapy. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  6. Case report: endurance electrical stimulation training improves skeletal muscle oxidative capacity in chronic spinal cord injury.

    Science.gov (United States)

    Ryan, Terence E; Erickson, Melissa L; Young, Hui-Ju; McCully, Kevin K

    2013-12-01

    To describe the use of a novel neuromuscular electrical stimulation (NMES) endurance exercise protocol and its effects on skeletal muscle oxidative capacity. Case report, pre/post intervention. University-based trial. A 39-year-old man who suffered a motor complete spinal cord injury (C5-6, ASIA Impairment Scale grade A). Twenty-four weeks of endurance NMES that consisted of progressive increases in the twitch frequency, duration of sessions, and sessions per week. Mitochondrial capacity was measured, in vivo, as the rate of recovery of muscle oxygen consumption using near-infrared spectroscopy. The rate of recovery of muscle oxygen consumption increased approximately 3-fold from 0.52 to 1.43, 1.46, and 1.40/min measured on 3 separate occasions during week 12 of training, and 1.57/min after 24 weeks of NMES endurance training. The findings of this study suggest that NMES endurance training using twitches can increase mitochondrial capacity to comparable levels measured in nonparalyzed muscles of sedentary able-bodied controls. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  7. Afferent electrical stimulation during cycling improves spinal processing of sensorimotor function after incomplete spinal cord injury.

    Science.gov (United States)

    Piazza, Stefano; Serrano-Muñoz, Diego; Gómez-Soriano, Julio; Torricelli, Diego; Segura-Fragosa, Antonio; Pons, José Luis; Taylor, Julian

    2017-01-01

    Appropriate afferent feedback delivery during the execution of motor tasks is important for rehabilitation after incomplete spinal cord injury (iSCI). However, during leg-cycling therapy, the plantar afferent feedback is minimal. We hypothesize that the augmentation of sensory input by combining cycling with a locomotor-like stimulation of plantar cutaneous innervations (ES-cycling), might help to restore proper spinal processing of sensorimotor function. Thirteen non-injured subjects and 10 subjects with iSCI performed 10 minutes of cycling and, on another session, of ES-cycling. To assess spinal processing of sensorimotor function, soleus H-reflex response was tested following a conditioning plantar electrical stimulation applied at 25-100 ms inter-stimulus intervals (ISI's), measured before and after the execution of the tasks. Before tasks execution, the conditioned H-reflex response was modulated in non-injured subjects, and absent in subjects with iSCI; after cycling, modulation profiles were unchanged. However, after ES-cycling a significant increase in H-reflex excitability was observed in the non-injured group at 100 ms ISI (p spinal processing of sensorimotor function. Reflex modulation recovery after ES-cycling may indicate the partial reactivation of these mechanisms.

  8. Detection of (reversible) myocardial ischemic injury by means of electrical bioimpedance.

    Science.gov (United States)

    Mellert, Fritz; Winkler, Kai; Schneider, Christian; Dudykevych, Taras; Welz, Armin; Osypka, Markus; Gersing, Eberhard; Preusse, Claus J

    2011-06-01

    The scope of this paper was to determine whether ischemic and reperfusion damage in cardiac surgery can be detected by measurement of electrical bioimpedance (EBI). Conventional pacing wires were replaced by pacing wires with sputtered iridium coating in order to reduce polarization associated with two-electrode impedance measurements. A custom-built bioimpedance analyzer (Osypka Medical GmbH, Berlin, Germany) measured the real part of impedance Re(Z) and the phase (ϕ) at three frequencies (1, 10, and 1000 kHz) and determined an extracellular space index (EZRI) as the quotient of Re(Z) at 1000 kHz and Re(Z) at 1 kHz. Our study included six patients (conventional coronary artery bypass graft, age 68.1 ± 8.3 years) subject to routine cardioplegic ischemia and reperfusion. Preischemic bioimpedance measurements were not impaired by interference of the beating heart. Intraischemically, bioimpedance at 1 kHz and phase at 10 kHz increased until opening of a bypass graft, which is probably induced by closure of gap junctions and cell swelling processes. After cross clamping, EZRI slowly decreased as an effect of mild cell swelling. After ischemia, values returned almost to baseline measurements, indicating sufficient reperfusion processes. Measurement of EBI correlates with myocardial ischemic injury and is applicable in a two-electrode setup providing low-polarization pacing wires.

  9. Cathodic voltage-controlled electrical stimulation of titanium for prevention of methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii biofilm infections.

    Science.gov (United States)

    Canty, Mary; Luke-Marshall, Nicole; Campagnari, Anthony; Ehrensberger, Mark

    2017-01-15

    Antibiotic resistance of bacterial biofilms limits available treatment methods for implant-associated orthopaedic infections. This study evaluated the effects of applying cathodic voltage-controlled electrical stimulations (CVCES) of -1.5V and -1.8V (vs. Ag/AgCl) to coupons of commercially pure titanium (cpTi) incubated in cultures of methicillin-resistant Staphylococcus aureus (MRSA) and Acinetobacter baumannii (A. baumannii) as a method of preventing bacterial attachment. Stimulations were applied for 2, 4, and 8h and coupon-associated and planktonic colony-forming units (CFU) were enumerated following stimulation. Compared to open circuit potential (OCP) controls, CVCES for 4h at -1.8V significantly reduced coupon-associated MRSA CFU by 99.9% (1.30×104vs. 4.45×107, p=0.047) and A. baumannii coupon-associated CFU by 99.9% (1.64×104vs. 5.93×107, p=0.001) and reduced planktonic CFU below detectable levels for both strains. CVCES at -1.8V for 8h also reduced coupon-associated and planktonic CFU below detectable levels for each strain. CVCES at -1.5V for 4 and 8h, and -1.8V for 2h did not result in clinically relevant reductions. For 4 and 8h stimulations, the current density was significantly higher for -1.8V than -1.5V, an effect directly related to the rate of water and oxygen reduction on the cpTi surface. This significantly increased the pH, a suspected influence in decreased CFU viability. The voltage-dependent electrochemical properties of cpTi likely contribute to the observed antimicrobial effects of CVCES. This study revealed that CVCES of titanium could prevent coupon-associated and planktonic CFU of Gram-positive MRSA and Gram-negative A. baumannii from reaching detectable levels in a magnitude-dependent and time-dependent manner. Periprosthetic joint infection is a devastating outcome of total joint arthroplasty and has led to increased patient morbidity and rising healthcare costs. Current treatments are limited by the growing prevalence of

  10. Quantitative Brain Electrical Activity in the Initial Screening of Mild Traumatic Brain Injuries

    Directory of Open Access Journals (Sweden)

    Robert Chabot

    2012-12-01

    Full Text Available Introduction: The incidence of emergency department (ED visits for Traumatic Brain Injury (TBIin the United States exceeds 1,000,000 cases/year with the vast majority classified as mild (mTBI.Using existing computed tomography (CT decision rules for selecting patients to be referred for CT,such as the New Orleans Criteria (NOC, approximately 70% of those scanned are found to havea negative CT. This study investigates the use of quantified brain electrical activity to assess itspossible role in the initial screening of ED mTBI patients as compared to NOC.Methods: We studied 119 patients who reported to the ED with mTBI and received a CT. Using ahand-held electroencephalogram (EEG acquisition device, we collected data from frontal leadsto determine the likelihood of a positive CT. The brain electrical activity was processed off-line togenerate an index (TBI-Index, biomarker. This index was previously derived using an independentpopulation, and the value found to be sensitive for significant brain dysfunction in TBI patients. Wecompared this performance of the TBI-Index to the NOC for accuracy in prediction of positive CTfindings.Results: Both the brain electrical activity TBI-Index and the NOC had sensitivities, at 94.7% and92.1% respectively. The specificity of the TBI-Index was more than twice that of NOC, 49.4%and 23.5% respectively. The positive predictive value, negative predictive value and the positivelikelihood ratio were better with the TBI-Index. When either the TBI-Index or the NOC are positive(combining both indices the sensitivity to detect a positive CT increases to 97%.Conclusion: The hand-held EEG device with a limited frontal montage is applicable to the EDenvironment and its performance was superior to that obtained using the New Orleans criteria.This study suggests a possible role for an index of brain function based on EEG to aid in the acuteassessment of mTBI patients.

  11. Electrical transport properties and laser-induced voltage effect in La0.8Ca0.2MnO3 epitaxial thin films

    Science.gov (United States)

    Theingi, Mya; Ma, Ji; Zhang, Hui; Cui, Qi; Yi, Jianhong; Chen, Qingming

    2014-03-01

    La0.8Ca0.2MnO3 (LCMO) thin films about 200 nm thickness were grown on untilted and tilted (5°, 10° and 15°) LaAlO3 (100) single crystal substrates by pulsed laser deposition technique. Electrical properties of the epitaxial thin films were studied by conventional four-probe technique and the anisotropic thermoelectric properties of the films grown on the tilted substrates have been investigated by laser-induced voltage (LIV) measurements. X-ray diffraction analysis and atomic force microscopy results show that the prepared LCMO thin films have a single phase and high crystalline quality. The remarkably large temperature coefficient of resistance (TCR) values (above 11 %/K) are observed in the all films. TCR value reaches 18 %/K on the film grown on 10° tilted substrate. The intensity of LIV signals monotonously increases with the tilting angles, and the largest signal is 148 mV with the fast time response 229 ns for the film grown on 15° tilted substrate.

  12. Proteome changes in the insoluble protein fraction of bovine Longissimus dorsi muscle as a result of low-voltage electrical stimulation.

    Science.gov (United States)

    Bjarnadóttir, Stefanía Guðrún; Hollung, Kristin; Høy, Martin; Veiseth-Kent, Eva

    2011-10-01

    Changes induced by low-voltage electrical stimulation (ES; 0-95 V for 8 s; 95 V for 32 s) in the insoluble protein fraction of bovine longissimus dorsi (LD) muscle at 1 and 24h post-ES were investigated by proteomics. Protein abundance patterns from ten Norwegian Red (NRF) young bulls were compared, and significant changes due to ES were found by rotation test and partial least square (PLS) regression analyses. Five protein spots showed lower abundance in ES samples at both sampling times, and in addition, 10 proteins at 1 h post-ES and 13 proteins at 24 h post-ES changed significantly in abundance due to ES. Reduced abundance of full-length structural proteins in ES samples indicates an accelerated proteolysis due to ES. Moreover, increased abundance of small heat shock proteins indicates earlier initiation of stress responses due to ES. These findings provide a better understanding of the biochemical processes taking place as a result of ES during post mortem storage of meat. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Electrical stimulation of the sacral dermatomes in spinal cord injury: effect on rectal manometry and bowel emptying.

    Science.gov (United States)

    Frost, F; Hartwig, D; Jaeger, R; Leffler, E; Wu, Y

    1993-07-01

    The impairment in defecation function that comes as a result of spinal cord injury may have a significant negative impact upon quality of life. Electrical stimulation (ES) of the somatic nervous system has been used to elicit autonomic reflexes in animals, before and after spinal cord transection. To determine whether ES might be used to promote bowel emptying, seven persons with recent spinal cord injury (SCI) and seven control subjects were studied. Electrical stimulation of the second sacral dermatome was applied during rectal manometry in both groups, and ES was added to the bowel programs of SCI patients. A significant rise in the number of rectal pressure spikes was noted in both groups after application of ES (p dermatomes can result in a change in the bowel activity of the recto-sigmoid colon. To date, no clinical effect on bowel emptying has been demonstrated.

  14. Pattern of burn injury in hang-glider pilots.

    Science.gov (United States)

    Campbell, D C; Nano, T; Pegg, S P

    1996-06-01

    High-voltage electrical injury has been well documented in a number of situations, such as the occupational hazard of linesmen and construction workers, and in the context of overhead railway power lines. Two cases of hang-glider pilots contacting 11,000-volt power lines have recently been treated in the Royal Brisbane Hospital Burns Unit. They demonstrate an interesting pattern of injury, not described in current burns literature, involving both hand and lower abdominal burns. Both patients sustained full-thickness patches of burn injury, with underlying muscle damage and peripheral neurological injury. This distribution of injury seems to be closely related to the design of the hang glider.

  15. The effects of an electrical muscle stimulation training intervention on physiological measures in a spinal cord injury male

    OpenAIRE

    McCormack, Kirsti; Carty, Amanda; Coughlan, Garrett; Crowe, Louis; Caulfield, Brian

    2010-01-01

    Participation in aerobic exercise activity is considered necessary for individuals with spinal cord injury (SCI) to reduce the potential development of common co-morbidities associated with SCI such as cardiovascular (CV) disease, reduced bone mineral density (BMD), increases in body fat and decreases in lean body mass. Functional Electrical Stimulation (FES) has been advocated as offering a feasible exercise regime to SCI individuals. FES studies have reported improvements in BMD, CV fitness...

  16. Optimizing Bi2O3 and TiO2 to achieve the maximum non-linear electrical property of ZnO low voltage varistor.

    Science.gov (United States)

    Abdollahi, Yadollah; Zakaria, Azmi; Aziz, Raba'ah Syahidah; Tamili, Siti Norazilah Ahmad; Matori, Khamirul Amin; Shahrani, Nuraine Mariana Mohd; Sidek, Nurhidayati Mohd; Dorraj, Masoumeh; Moosavi, Seyedehmaryam

    2013-01-01

    In fabrication of ZnO-based low voltage varistor, Bi2O3 and TiO2 have been used as former and grain growth enhancer factors respectively. Therefore, the molar ratio of the factors is quit important in the fabrication. In this paper, modeling and optimization of Bi2O3 and TiO2 was carried out by response surface methodology to achieve maximized electrical properties. The fabrication was planned by central composite design using two variables and one response. To obtain actual responses, the design was performed in laboratory by the conventional methods of ceramics fabrication. The actual responses were fitted into a valid second order algebraic polynomial equation. Then the quadratic model was suggested by response surface methodology. The model was validated by analysis of variance which provided several evidences such as high F-value (153.6), very low P-value (<0.0001), adjusted R-squared (0.985) and predicted R-squared (0.947). Moreover, the lack of fit was not significant which means the model was significant. The model tracked the optimum of the additives in the design by using three dimension surface plots. In the optimum condition, the molars ratio of Bi2O3 and TiO2 were obtained in a surface area around 1.25 point that maximized the nonlinear coefficient around 20 point. Moreover, the model predicted the optimum amount of the additives in desirable condition. In this case, the condition included minimum standard error (0.35) and maximum nonlinearity (20.03), while molar ratio of Bi2O3 (1.24 mol%) and TiO2 (1.27 mol%) was in range. The condition as a solution was tested by further experiments for confirmation. As the experimental results showed, the obtained value of the non-linearity, 21.6, was quite close to the predicted model. Response surface methodology has been successful for modeling and optimizing the additives such as Bi2O3 and TiO2 of ZnO-based low voltage varistor to achieve maximized non-linearity properties.

  17. Bacterial voltage-gated sodium channels (BacNa(V)s) from the soil, sea, and salt lakes enlighten molecular mechanisms of electrical signaling and pharmacology in the brain and heart.

    Science.gov (United States)

    Payandeh, Jian; Minor, Daniel L

    2015-01-16

    Voltage-gated sodium channels (Na(V)s) provide the initial electrical signal that drives action potential generation in many excitable cells of the brain, heart, and nervous system. For more than 60years, functional studies of Na(V)s have occupied a central place in physiological and biophysical investigation of the molecular basis of excitability. Recently, structural studies of members of a large family of bacterial voltage-gated sodium channels (BacNa(V)s) prevalent in soil, marine, and salt lake environments that bear many of the core features of eukaryotic Na(V)s have reframed ideas for voltage-gated channel function, ion selectivity, and pharmacology. Here, we analyze the recent advances, unanswered questions, and potential of BacNa(V)s as templates for drug development efforts. Copyright © 2014. Published by Elsevier Ltd.

  18. A report of anticipated benefits of functional electrical stimulation after spinal cord injury.

    Science.gov (United States)

    Gorgey, Ashraf S; Harnish, Christopher R; Daniels, Jonathan A; Dolbow, David R; Keeley, Allison; Moore, Jewel; Gater, David R

    2012-03-01

    Functional electrical stimulation (FES) has been regularly used to offset several negative body composition and metabolic adaptations following spinal cord injury (SCI). However, the outcomes of many FES trials appear to be controversial and incoherent. To document the potential consequences of several factors (e.g. pain, spasms, stress and lack of dietary control) that may have attenuated the effects on body composition and metabolic profile despite participation in 21 weeks of FES training. A 29-year-old man with T6 complete SCI participated in 21 weeks of FES, 4 days per week. Prior to and following training, the participant performed arm-crank-graded exercise testing to measure peak VO(2). Tests conducted included anthropometrics and dual energy X-ray absorptiometry body composition assessments, resting energy expenditure, plasma lipid profiles and intravenous glucose tolerance tests. The participant frequently reported increasing pain, stress and poor eating habits. VO(2) peak decreased by 2.4 ml/kg/minute, body mass increased by 8.5 kg, and body mass index increased from 25 to 28 kg/m(2). Waist and abdominal circumferences increased by 2-4 cm, while %fat mass increased by 5.5%. Absolute increases in fat mass and fat-free mass of 8.4 and 1 kg, respectively, were reported. Fasting and peak plasma glucose increased by 12 and 14.5%, while lipid panel profiles were negatively impacted. Failure to control for the listed negative emerging factors may obscure the expected body composition and metabolic profile adaptations anticipated from FES training.

  19. Non-isolated DC-AC converter with high voltage gain for autonomous systems of electric power; Conversor CC-CA nao isolado com alto ganho de tensao para aplicacao em sistemas autonomos de energia eletrica

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, George Cajazeiras [Centro Federal de Educacao Tecnologica do Ceara (CEFET/CE), Fortaleza, CE (Brazil); Torrico-Bascope, Rene P. [Universidade Federal do Ceara (PPGEE/UFC), Fortaleza, CE (Brazil). Programa de Pos Graduacao em Engenharia Eletrica; Borges Neto, Manuel Rangel [Centro Federal de Educacao Tecnologica de Petrolina (CEFET-PET), PE (Brazil)

    2008-07-01

    A non-isolated DC-AC converter with high voltage gain with two output sinusoidal voltage - 110 V and 220 V - and frequency 60 Hz for application in autonomous systems of electric power is proposed in this work. This topology consists of a boost converter with high voltage gain, based on three-state switching cell combined with a double half bridge inverter. This configuration type the size and the cost are reduced and the efficiency is gotten better, due to the reduced number of switches. The converters that compose this topology operate with high frequency, reducing the volume of the magnetic materials. can be mention as important characteristics: the voltage stress across the switches of the boost converter are low, due they be naturally clamped by one output filter capacitor, which allows the utilization of switches with lower conduction resistances, and the waveforms of the output voltage of the double half bridge inverter supplies for the load it is sinusoidal and it possesses low harmonic content. (author)

  20. Compact, Lightweight, High Voltage Propellant Isolators Project

    Data.gov (United States)

    National Aeronautics and Space Administration — TA&T, Inc. proposes an enabling fabrication process for high voltage isolators required in high power solar electric and nuclear electric propulsion (SEP and...

  1. The effect of surface electric stimulation of the gluteal muscles on the interface pressure in seated people with spinal cord injury

    NARCIS (Netherlands)

    van Londen, A.; Herwegh, M.; van der Zee, C.H.; Daffertshofer, A.; Smit, C.A.; Niezen, A.; Janssen, T.W.J.

    2008-01-01

    van Londen A, Herwegh M, van der Zee CH, Daffertshofer A, Smit CA, Niezen A, Janssen TW. The effect of surface electric stimulation of the gluteal muscles on the interface pressure in seated people with spinal cord injury. Objective: To study effects of surface electric stimulation of the gluteal

  2. Diagnostic Accuracy of a New Cardiac Electrical Biomarker for Detection of Electrocardiogram Changes Suggestive of Acute Myocardial Ischemic Injury

    Science.gov (United States)

    Schreck, David M; Fishberg, Robert D

    2014-01-01

    Objective A new cardiac “electrical” biomarker (CEB) for detection of 12-lead electrocardiogram (ECG) changes indicative of acute myocardial ischemic injury has been identified. Objective was to test CEB diagnostic accuracy. Methods This is a blinded, observational retrospective case-control, noninferiority study. A total of 508 ECGs obtained from archived digital databases were interpreted by cardiologist and emergency physician (EP) blinded reference standards for presence of acute myocardial ischemic injury. CEB was constructed from three ECG cardiac monitoring leads using nonlinear modeling. Comparative active controls included ST voltage changes (J-point, ST area under curve) and a computerized ECG interpretive algorithm (ECGI). Training set of 141 ECGs identified CEB cutoffs by receiver-operating-characteristic (ROC) analysis. Test set of 367 ECGs was analyzed for validation. Poor-quality ECGs were excluded. Sensitivity, specificity, and negative and positive predictive values were calculated with 95% confidence intervals. Adjudication was performed by consensus. Results CEB demonstrated noninferiority to all active controls by hypothesis testing. CEB adjudication demonstrated 85.3–94.4% sensitivity, 92.5–93.0% specificity, 93.8–98.6% negative predictive value, and 74.6–83.5% positive predictive value. CEB was superior against all active controls in EP analysis, and against ST area under curve and ECGI by cardiologist. Conclusion CEB detects acute myocardial ischemic injury with high diagnostic accuracy. CEB is instantly constructed from three ECG leads on the cardiac monitor and displayed instantly allowing immediate cost-effective identification of patients with acute ischemic injury during cardiac rhythm monitoring. PMID:24118724

  3. Stimulation parameter optimization for functional electrical stimulation assisted gait in human spinal cord injury using response surface methodology.

    Science.gov (United States)

    Kim, Yongchul; Schmit, Brian D; Youm, Youngil

    2006-06-01

    The aims of this study were to identify the reflex moment induced by flexion withdrawal reflex and to optimize stimulation parameters for restoring swing motion with respect to initial kinematic conditions in human with spinal cord injury. The influence of hip position and passive movement in the reflex moment were tested in six subjects with chronic spinal cord injury. The two-dimensional dynamic models consisted of thigh, shank and foot segments were developed to compute the swing-phase response and the response surface method was also used to optimize stimulation parameters for restoration of gait by functional electrical stimulation. At three different hip positions, significant linear relationship was found between the reflex moment and hip angle (P spinal cord injured patients. From dynamic simulation, we concluded that optimal solutions of pulse amplitude, frequency and duration time of burst for electrical stimulation assisted gait were influenced by initial kinematic conditions at toe-off. The reflex model and the results of this study can be applied to the design and control strategies of neuroprosthetic devices using functional electrical stimulation for spinal cord injured patients.

  4. Post electrical or lightning injury syndrome: a proposal for an American Psychiatric Association's Diagnostic and Statistical Manual formulation with implications for treatment

    Directory of Open Access Journals (Sweden)

    Christopher J Andrews

    2017-01-01

    Full Text Available In the past, victims of electrical and lightning injuries have been assessed in a manner lacking a systematic formulation, and against ad hoc criteria, particularly in the area of neuropsychological disability. In this manner patients have, for example, only been partially treated, been poorly or incorrectly diagnosed, and have been denied the full benefit of compensation for their injuries. This paper contains a proposal for diagnostic criteria particularly for the neuropsychological aspects of the post injury syndrome. It pays attention to widely published consistent descriptions of the syndrome, and a new cluster analysis of post electrical injury patients. It formulates a proposal which could be incorporated into future editions of the American Psychiatric Association's Diagnostic and Statistical Manual (DSM. The major neuropsychological consequences include neurocognitive dysfunction, and memory subgroup dysfunction, with ongoing consequences, and sometimes including progressive or delayed psychiatric, cognitive, and/or neurological symptoms. The proposed diagnostic criteria insist on a demonstrated context for the injury, both specifying the shock circumstance, and also physical consequences. It allows for a certain delay in onset of symptoms. It recognizes exclusory conditions. The outcome is a proposal for a DSM classification for the post electrical or lightning injury syndrome. This proposal is considered important for grounding patient treatment, and for further treatment trials. Options for treatment in electrical or lightning injury are summarised, and future trials are foreshadowed.

  5. Post electrical or lightning injury syndrome: a proposal for an American Psychiatric Association's Diagnostic and Statistical Manual formulation with implications for treatment.

    Science.gov (United States)

    Andrews, Christopher J; Reisner, Andrew D; Cooper, Mary Ann

    2017-09-01

    In the past, victims of electrical and lightning injuries have been assessed in a manner lacking a systematic formulation, and against ad hoc criteria, particularly in the area of neuropsychological disability. In this manner patients have, for example, only been partially treated, been poorly or incorrectly diagnosed, and have been denied the full benefit of compensation for their injuries. This paper contains a proposal for diagnostic criteria particularly for the neuropsychological aspects of the post injury syndrome. It pays attention to widely published consistent descriptions of the syndrome, and a new cluster analysis of post electrical injury patients. It formulates a proposal which could be incorporated into future editions of the American Psychiatric Association's Diagnostic and Statistical Manual (DSM). The major neuropsychological consequences include neurocognitive dysfunction, and memory subgroup dysfunction, with ongoing consequences, and sometimes including progressive or delayed psychiatric, cognitive, and/or neurological symptoms. The proposed diagnostic criteria insist on a demonstrated context for the injury, both specifying the shock circumstance, and also physical consequences. It allows for a certain delay in onset of symptoms. It recognizes exclusory conditions. The outcome is a proposal for a DSM classification for the post electrical or lightning injury syndrome. This proposal is considered important for grounding patient treatment, and for further treatment trials. Options for treatment in electrical or lightning injury are summarised, and future trials are foreshadowed.

  6. Effects of functional electrical stimulation cycling exercise on bone mineral density loss in the early stages of spinal cord injury.

    Science.gov (United States)

    Lai, Chien-Hung; Chang, Walter Hong-Shong; Chan, Wing P; Peng, Chih-Wei; Shen, Li-Kuo; Chen, Jia-Jin J; Chen, Shih-Ching

    2010-02-01

    To determine whether bone mineral density loss after spinal cord injury can be attenuated by an early intervention with functional electrical stimulation cycling exercises (FESCE) and to ascertain whether the effect persists after FESCE is discontinued. A prospective study. Twenty-four individuals with spinal cord injury, 26-52 days after spinal cord injury, were divided into FESCE or control groups. FESCE was applied in the initial 3 months and then suspended in the subsequent 3 months. Bone mineral density in the femoral neck and distal femur was measured using dual energy X-ray absorptiometry before training, immediately after the initial 3 months of training, and at the end of the subsequent 3 months. The bone mineral density decrease rate in the distal femur in the FESCE group was significantly less than that in the control group during the initial 3 months. However, there was no significant difference in the subsequent 3 months. FESCE in the early stages of spinal cord injury can partly attenuate bone mineral density loss in the distal femur. However, bone mineral density loss in the distal femur cannot be ameliorated completely by FESCE. In addition, the effect on the attenuation of bone loss in the distal femur faded once FESCE was discontinued.

  7. Depression and recovery of reflex amplitude during electrical stimulation after spinal cord injury.

    Science.gov (United States)

    Clair-Auger, J M; Lagerquist, O; Collins, D F

    2013-04-01

    The aim of this study was to quantify, for the first time, H-reflexes evoked during prolonged trains of wide-pulse neuromuscular electrical stimulation (WP-NMES) in individuals with chronic spinal cord injury (SCI). We hypothesised that after the first H-reflex, reflex amplitudes would be depressed (due to post-activation depression), but would recover and this recovery would be enhanced after a "burst" of 100 Hz WP-NMES. Soleus M-waves and H-reflexes evoked during WP-NMES (1 ms pulse width) of the tibial nerve were quantified in nine individuals with SCI. WP-NMES was delivered in two patterns: "constant-frequency" (15 or 20 Hz for 12 s) and "burst-like" (15-100-15 Hz or 20-100-20 Hz; 4 s each phase) at an intensity that evoked an M-wave between 10% and 15% of the maximal M-wave (M(max)). During constant frequency stimulation, after the initial depression from the first to the second H-reflex (1st: 57% M(max); 2nd: 25% M(max)), H-reflexes did not recover significantly and were 37% M(max) at the end of the stimulus train. During the burst-like pattern, after the initial depression (1st: 62% M(max); 2nd: 30%), reflexes recovered completely by the end of the stimulation (to 55% M(max)) as they were not significantly different from the first H-reflex. M-waves were initially depressed (1st: 12% M(max); 2nd: 7% M(max)) then did not change throughout the stimulation and were not significantly different between stimulation patterns. An analysis of covariance indicated that the depression in M-wave amplitude did not account for the depression in H-reflex amplitude. Relatively large H-reflexes were recorded during both patterns of NMES. The brief burst of 100 Hz stimulation restored H-reflexes to their initial amplitudes, effectively reversing the effects of post-activation depression. For individuals with chronic SCI, generating contractions through central pathways may help reduce muscle atrophy and produce contractions that are more fatigue-resistant for rehabilitation

  8. Relationship between Sublethal Injury and Inactivation of Yeast Cells by the Combination of Sorbic Acid and Pulsed Electric Fields▿

    Science.gov (United States)

    Somolinos, M.; García, D.; Condón, S.; Mañas, P.; Pagán, R.

    2007-01-01

    The objective of this study was to investigate the occurrence of sublethal injury after the pulsed-electric-field (PEF) treatment of two yeasts, Dekkera bruxellensis and Saccharomyces cerevisiae, as well as the relation of sublethal injury to the inactivating effect of the combination of PEF and sorbic acid. PEF caused sublethal injury in both yeasts: more than 90% of surviving D. bruxellensis cells and 99% of surviving S. cerevisiae cells were sublethally injured after 50 pulses at 12 kV/cm in buffer at pHs of both 7.0 and 4.0. The proportion of sublethally injured cells reached a maximum after 50 pulses at 12.0 kV/cm (S. cerevisiae) or 16.5 kV/cm (D. bruxellensis), and it kept constant or progressively decreased at greater electric field strengths and with longer PEF treatments. Sublethally PEF-injured cells showed sensitivity to the presence of sorbic acid at a concentration of 2,000 ppm. A synergistic inactivating effect of the combination of PEF and sorbic acid was observed. Survivors of the PEF treatment were progressively inactivated in the presence of 2,000 ppm of sorbic acid at pH 3.8, with the combined treatments achieving more than log10 5 cycles of dead cells under the conditions investigated. This study has demonstrated the occurrence of sublethal injury after exposure to PEF, so yeast inactivation by PEF is not an all-or-nothing event. The combination of PEF and sorbic acid has proven to be an effective method to achieve a higher level of yeast inactivation. This work contributes to the knowledge of the mechanism of microbial inactivation by PEF, and it may be useful for improving food preservation by PEF technology. PMID:17468278

  9. Relationship between sublethal injury and inactivation of yeast cells by the combination of sorbic acid and pulsed electric fields.

    Science.gov (United States)

    Somolinos, M; García, D; Condón, S; Mañas, P; Pagán, R

    2007-06-01

    The objective of this study was to investigate the occurrence of sublethal injury after the pulsed-electric-field (PEF) treatment of two yeasts, Dekkera bruxellensis and Saccharomyces cerevisiae, as well as the relation of sublethal injury to the inactivating effect of the combination of PEF and sorbic acid. PEF caused sublethal injury in both yeasts: more than 90% of surviving D. bruxellensis cells and 99% of surviving S. cerevisiae cells were sublethally injured after 50 pulses at 12 kV/cm in buffer at pHs of both 7.0 and 4.0. The proportion of sublethally injured cells reached a maximum after 50 pulses at 12.0 kV/cm (S. cerevisiae) or 16.5 kV/cm (D. bruxellensis), and it kept constant or progressively decreased at greater electric field strengths and with longer PEF treatments. Sublethally PEF-injured cells showed sensitivity to the presence of sorbic acid at a concentration of 2,000 ppm. A synergistic inactivating effect of the combination of PEF and sorbic acid was observed. Survivors of the PEF treatment were progressively inactivated in the presence of 2,000 ppm of sorbic acid at pH 3.8, with the combined treatments achieving more than log10 5 cycles of dead cells under the conditions investigated. This study has demonstrated the occurrence of sublethal injury after exposure to PEF, so yeast inactivation by PEF is not an all-or-nothing event. The combination of PEF and sorbic acid has proven to be an effective method to achieve a higher level of yeast inactivation. This work contributes to the knowledge of the mechanism of microbial inactivation by PEF, and it may be useful for improving food preservation by PEF technology.

  10. Modeling and Simulation of Low Voltage Arcs

    NARCIS (Netherlands)

    Ghezzi, L.; Balestrero, A.

    2010-01-01

    Modeling and Simulation of Low Voltage Arcs is an attempt to improve the physical understanding, mathematical modeling and numerical simulation of the electric arcs that are found during current interruptions in low voltage circuit breakers. An empirical description is gained by refined electrical

  11. Macroeconomic Assessment of Voltage Sags

    Directory of Open Access Journals (Sweden)

    Sinan Küfeoğlu

    2016-12-01

    Full Text Available The electric power sector has changed dramatically since the 1980s. Electricity customers are now demanding uninterrupted and high quality service from both utilities and authorities. By becoming more and more dependent on the voltage sensitive electronic equipment, the industry sector is the one which is affected the most by voltage disturbances. Voltage sags are one of the most crucial problems for these customers. The utilities, on the other hand, conduct cost-benefit analyses before going through new investment projects. At this point, understanding the costs of voltage sags become imperative for planning purposes. The characteristics of electric power consumption and hence the susceptibility against voltage sags differ considerably among different industry subsectors. Therefore, a model that will address the estimation of worth of electric power reliability for a large number of customer groups is necessary. This paper introduces a macroeconomic model to calculate Customer Voltage Sag Costs (CVSCs for the industry sector customers. The proposed model makes use of analytical data such as value added, annual energy consumption, working hours, and average outage durations and provides a straightforward, credible, and easy to follow methodology for the estimation of CVSCs.

  12. Electrical stimulation of the vagus nerve protects against cerebral ischemic injury through an anti-infammatory mechanism

    Science.gov (United States)

    Xiang, Yao-xian; Wang, Wen-xin; Xue, Zhe; Zhu, Lei; Wang, Sheng-bao; Sun, Zheng-hui

    2015-01-01

    Vagus nerve stimulation exerts protective effects against ischemic brain injury; however, the underlying mechanisms remain unclear. In this study, a rat model of focal cerebral ischemia was established using the occlusion method, and the right vagus nerve was given electrical stimulation (constant current of 0.5 mA; pulse width, 0.5 ms; frequency, 20 Hz; duration, 30 seconds; every 5 minutes for a total of 60 minutes) 30 minutes, 12 hours, and 1, 2, 3, 7 and 14 days after surgery. Electrical stimulation of the vagus nerve substantially reduced infarct volume, improved neurological function, and decreased the expression levels of tumor necrosis factor-α and interleukin-6 in rats with focal cerebral ischemia. The experimental findings indicate that the neuroprotective effect of vagus nerve stimulation following cerebral ischemia may be associated with the inhibition of tumor necrosis factor-α and interleukin-6 expression. PMID:26170817

  13. Análisis estadístico de la caída de tensión en un sistema eléctrico de baja tensión; Statistical analysis of the voltage drop in a low voltage electrical system

    Directory of Open Access Journals (Sweden)

    Juan M. Astorga Gómez

    2013-06-01

    Full Text Available En este trabajo se presenta un enfoque estadístico para la evaluación de la caída de tensión en un sistema eléctrico de baja tensión, basado en la aplicación de dos herramientas básicas del control estadístico de procesos conocidas como cartas de control y análisis de capacidad de procesos. Se muestran los resultados para dos sistemas de prueba, se realizan las pruebas de normalidad y autocorrelación parcial para las muestras, se interpretan los resultados de las cartas de control Xbarra-S y se evalúa la capacidad del proceso considerando las bases del mejoramiento de la calidad. Los sistemas de prueba usados en este trabajo son un sistema eléctrico monofásico de baja tensión y un sistema eléctrico trifásico de baja tensión. El objetivo principal de este trabajo es evaluar el estado de control estadístico de la variable de proceso “caída de tensión”, como herramienta para el mejoramiento continuo de los procesos eléctricos.  This paper presents a statistical approach for the evaluation of the voltage drop in a low voltage electrical system, based on the application of two basic tools of statistical process control known as control charts and process capability analysis. The results for two test systems are shown, testing of normality and partial autocorrelation for samples are performed, the results of the control charts Xbar-S are interpreted and the process capability analysis are assessed considering the foundations for the quality improvement. The test systems used in this work are one electrical system single-phase low voltage and one electrical system of three-phase low voltage. The main objective of this paper is to evaluate the state of statistical control of the process variable "voltage drop", as a tool for continuous improvement of the electrical process.

  14. A minimal dose of electrically induced muscle activity regulates distinct gene signaling pathways in humans with spinal cord injury.

    Directory of Open Access Journals (Sweden)

    Michael A Petrie

    Full Text Available Paralysis after a spinal cord injury (SCI induces physiological adaptations that compromise the musculoskeletal and metabolic systems. Unlike non-SCI individuals, people with spinal cord injury experience minimal muscle activity which compromises optimal glucose utilization and metabolic control. Acute or chronic muscle activity, induced through electrical stimulation, may regulate key genes that enhance oxidative metabolism in paralyzed muscle. We investigated the short and long term effects of electrically induced exercise on mRNA expression of human paralyzed muscle. We developed an exercise dose that activated the muscle for only 0.6% of the day. The short term effects were assessed 3 hours after a single dose of exercise, while the long term effects were assessed after training 5 days per week for at least one year (adherence 81%. We found a single dose of exercise regulated 117 biological pathways as compared to 35 pathways after one year of training. A single dose of electrical stimulation increased the mRNA expression of transcriptional, translational, and enzyme regulators of metabolism important to shift muscle toward an oxidative phenotype (PGC-1α, NR4A3, IFRD1, ABRA, PDK4. However, chronic training increased the mRNA expression of specific metabolic pathway genes (BRP44, BRP44L, SDHB, ACADVL, mitochondrial fission and fusion genes (MFF, MFN1, MFN2, and slow muscle fiber genes (MYH6, MYH7, MYL3, MYL2. These findings support that a dose of electrical stimulation (∼10 minutes/day regulates metabolic gene signaling pathways in human paralyzed muscle. Regulating these pathways early after SCI may contribute to reducing diabetes in people with longstanding paralysis from SCI.

  15. Tidal recruitment assessed by electrical impedance tomography and computed tomography in a porcine model of lung injury*.

    Science.gov (United States)

    Muders, Thomas; Luepschen, Henning; Zinserling, Jörg; Greschus, Susanne; Fimmers, Rolf; Guenther, Ulf; Buchwald, Miriam; Grigutsch, Daniel; Leonhardt, Steffen; Putensen, Christian; Wrigge, Hermann

    2012-03-01

    To determine the validity of electrical impedance tomography to detect and quantify the amount of tidal recruitment caused by different positive end-expiratory pressure levels in a porcine acute lung injury model. Randomized, controlled, prospective experimental study. Academic research laboratory. Twelve anesthetized and mechanically ventilated pigs. Acute lung injury was induced by central venous oleic acid injection and abdominal hypertension in seven animals. Five healthy pigs served as control group. Animals were ventilated with positive end-expiratory pressure of 0, 5, 10, 15, 20, and 25 cm H2O, respectively, in a randomized order. At any positive end-expiratory pressure level, electrical impedance tomography was obtained during a slow inflation of 12 mL/kg of body weight. Regional-ventilation-delay indices quantifying the time until a lung region reaches a certain amount of impedance change were calculated for lung quadrants and for every single electrical impedance tomography pixel, respectively. Pixel-wise calculated regional-ventilation-delay indices were plotted in a color-coded regional-ventilation-delay map. Regional-ventilation-delay inhomogeneity that quantifies heterogeneity of ventilation time courses was evaluated by calculating the scatter of all pixel-wise calculated regional-ventilation-delay indices. End-expiratory and end-inspiratory computed tomography scans were performed at each positive end-expiratory pressure level to quantify tidal recruitment of the lung. Tidal recruitment showed a moderate inter-individual (r = .54; p electrical impedance tomography during a slow inflation of 12 mL/kg of body weight and visualized using ventilation delay maps. Our experimental data suggest that the impedance tomography-based analysis of regional-ventilation-delay inhomogeneity provides a good estimate of the amount of tidal recruitment and may be useful to individualize ventilatory settings.

  16. Increase in the number of distributed power generation installations in electricity distribution grids - Simulation in a 16 kV medium-voltage network; Zunahme der dezentralen Energieerzeugungsanlagen in elektrischen Verteilnetzen: Simulationen im 16 kV Mittelspannungsnetz des AEW

    Energy Technology Data Exchange (ETDEWEB)

    Hoeckel, M.; Luechinger, P.

    2003-07-01

    This is the seventh part of a ten-part final report for the Swiss Federal Office of Energy (SFOE) on a project that looked into potential problems relating to the Swiss electricity distribution grid with respect to the increasing number of distributed power generation facilities being put into service. The identification of special conditions for the grid's operation and future development that take increasing decentralised power production into account are discussed. The results of the project activities encompass the analysis and evaluation of various problem areas associated with planning and management of the grid during normal operation and periods of malfunction, as well as required modifications to safety systems and grid configurations. This sixth appendix to the main report presents and discusses the results of simulations made on the basis of the real-life 16 kV medium-voltage distribution network operated by the Aargovian electricity utility AEW. This appendix describes the simulation methods used and the basic characteristics of medium-voltage networks and distributed generation facilities. Different types of load profiles, including domestic and industrial loads, are discussed. The results of the simulations are presented in graphical form and provide profiles of voltage and current, active and reactive power and further mains characteristics for varying load conditions. Also, daily profiles for situations with and without distributed generation are presented and short-circuit simulations and grid dynamics are discussed.

  17. Effect of electrical charges and fields on injury and viability of airborne bacteria.

    Science.gov (United States)

    Mainelis, Gediminas; Górny, Rafał L; Reponen, Tiina; Trunov, Mikhaylo; Grinshpun, Sergey A; Baron, Paul; Yadav, Jagjit; Willeke, Klaus

    2002-07-20

    In this study, the effects of the electric charges and fields on the viability of airborne microorganisms were investigated. The electric charges of different magnitude and polarity were imparted on airborne microbial cells by a means of induction charging. The airborne microorganisms carrying different electric charge levels were then extracted by an electric mobility analyzer and collected using a microbial sampler. It was found that the viability of Pseudomonas fluorescens bacteria, used as a model for sensitive bacteria, carrying a net charge from 4100 negative to 30 positive elementary charges ranged between 40% and 60%; the viability of the cells carrying >2700 positive charges was below 1.5%. In contrast, the viability of the stress-resistant spores of Bacillus subtilis var. niger (used as simulant of anthrax-causing Bacillus anthracis spores when testing bioaerosol sensors in various studies), was not affected by the amount of electric charges on the spores. Because bacterial cells depend on their membrane potential for basic metabolic activities, drastic changes occurring in the membrane potential during aerosolization and the local electric fields induced by the imposed charges appeared to affect the sensitive cells' viability. These findings facilitate applications of electric charging for environmental control purposes involving sterilization of bacterial cells by imposing high electric charges on them. The findings from this study can also be used in the development of new bioaerosol sampling methods based on electrostatic principles. Copyright 2002 Wiley Periodicals, Inc.

  18. Development of ST Elevation Myocardial Infarction and Atrial Fibrillation after an Electrical Injury

    Directory of Open Access Journals (Sweden)

    Erdal Gursul

    2015-01-01

    Full Text Available Electrical energy is a type of energy that is commonly used in daily life. Ventricular premature beats, ventricular tachycardia, ventricular fibrillation, atrial tachycardia, atrial fibrillation, bundle branch blocks, and AV block are arrhythmic complications that are encountered in case of electric shocks. Myocardial infarction is one of the rarely seen complications of electric shocks yet it has fatal outcomes. Coronary arteries were detected to be normal in most of the patients who had myocardial infarction following an electric shock. So, etiology of myocardial infarction is thought to be unrelated to coronary atherosclerosis in these cases. Coronary artery vasospasm is thought to be the primary etiological cause. In our case report, we presented a patient who developed ST elevation MI with atrial fibrillation after an electric shock.

  19. Electrically pumped random lasing with an onset voltage of sub-3 V from ZnO-based light-emitting devices featuring nanometer-thick MoO3 interlayers.

    Science.gov (United States)

    Wang, Can-Xing; Lv, Chun-Yan; Zhu, Chen; Gao, Zhi-Fei; Li, Dong-Sheng; Ma, Xiang-Yang; Yang, De-Ren

    2015-05-28

    We have previously reported on electrically pumped random lasing (RL) with onset voltages at least 3.3 V from ZnO-based light-emitting devices with metal-insulator-semiconductor (MIS) structures in the form of Au/SiO2/ZnO. Here, by inserting an ∼5 nm thick MoO3 layer between SiO2 and ZnO films in the aforementioned MIS structured device, the RL onset voltage is decreased to only ∼2.6 V and, moreover, the output optical power is multiplied several times. Such improved RL performance is ascribed to the enhanced injection of holes into ZnO via the MoO3 interlayer that features a low-lying conductive band and therefore a large work function.

  20. Neuro-fuzzy-wavelet network for detection and classification of the voltage disturbances in electrical power system; Rede neuro-fuzzy-wavelet para deteccao e classificacao de anomalias de tensao em sistemas eletricos de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Malange, Fernando C.V. [Universidade do Estado de Mato Grosso (UEMT), Caceres, MT (Brazil). Dept. de Computacao], E-mail: fmalange@gmail.com; Minussi, Carlos R. [Universidade Estadual Paulista (UNESP), Ilha Solteira, SP (Brazil). Dept. de Engenharia Eletrica], E-mail: minussi@dee.feis.unesp.br

    2009-07-01

    A methodology for identifying and classifying voltage disturbances (harmonics, voltage sag, etc.) using fuzzy ARTMAP neural networks is presented. It is an ART (adaptive resonance theory) architecture family neural network that presents the stability and plasticity properties, which are fundamental requests for developing a reliable electrical systems with reduced processing time. Stability means a guarantee of good solutions; plasticity allows realize the training without restart the system every time there are new patterns to be stored in a weight matrix of the neural network. The training is realized from the wave forms provided by the acquisition data system, using the wavelets theory to generate the coefficients that constitute the input patterns of the neural network. Results from simulations show that the accuracy index is nearly 100%. (author)

  1. Early application of tail nerve electrical stimulation-induced walking training promotes locomotor recovery in rats with spinal cord injury

    Science.gov (United States)

    Zhang, S-x; Huang, F; Gates, M; Shen, X; Holmberg, E G

    2016-01-01

    Study design: This is a randomized controlled prospective trial with two parallel groups. Objectives: The objective of this study was to determine whether early application of tail nerve electrical stimulation (TANES)-induced walking training can improve the locomotor function. Setting: This study was conducted in SCS Research Center in Colorado, USA. Methods: A contusion injury to spinal cord T10 was produced using the New York University impactor device with a 25 -mm height setting in female, adult Long–Evans rats. Injured rats were randomly divided into two groups (n=12 per group). One group was subjected to TANES-induced walking training 2 weeks post injury, and the other group, as control, received no TANES-induced walking training. Restorations of behavior and conduction were assessed using the Basso, Beattie and Bresnahan open-field rating scale, horizontal ladder rung walking test and electrophysiological test (Hoffmann reflex). Results: Early application of TANES-induced walking training significantly improved the recovery of locomotor function and benefited the restoration of Hoffmann reflex. Conclusion: TANES-induced walking training is a useful method to promote locomotor recovery in rats with spinal cord injury. PMID:27067652

  2. Epidural and transcutaneous spinal electrical stimulation for restoration of movement after incomplete and complete spinal cord injury.

    Science.gov (United States)

    Mayr, Winfried; Krenn, Matthias; Dimitrijevic, Milan R

    2016-12-01

    The Purpose of this review is to outline and explain the therapeutic use of electrical spinal cord stimulation (SCS) for modification of spinal motor output. Central functional stimulation provides afferent input to posterior root neurons and is applied to improve volitional movements, posture and their endurance, control spasticity, and improve bladder function or perfusion in the lower limbs. Clinical accomplishments strongly depend on each individual's physiological state and specific methodical adaptation to that physiological state. Effectiveness of this neuromodulory technique for changing motor control after spinal cord injury (SCI) continues to be explored along with the underlying mechanisms of its effect in people with complete and incomplete spinal cord injuries. There are extensive studies of tonic and rhythmical activity elicited from the lumbar cord as well as data demonstrating augmentation of residual volitional activity. Recent studies have focused on verifying if and how SCS can modify features of neurocontrol in ambulatory spinal cord patients. In this review, we emphasize recent publications of research revealing that SCS can substitute for the reduced brain drive for control of excitability in people with SCI. Artificially replacing diminished or lost brain control over the spinal cord has limitations. A fundamental requirement for successful SCS application is analysis of each individual's residual postinjury neural function. This will allow a better understanding of the physiological interactions between SCS and spinal cord motor control below injury and provide criteria for its application. Finally, the publication of both successful and failed applications of SCS will be crucial for gaining future progress.

  3. Electricity and fishing - a dangerous mix.

    Science.gov (United States)

    Fodor, Lucian; Bota, Ioan O; Abbas, Yusuf; Fodor, Marius; Ciuce, Constantin

    2011-05-01

    The advent of fishing rods made of carbon fiber and graphite rods has greatly increased the risks of electrical injuries associated with fishing. The braided fishing lines and metal hooks put the fishermen at risk for electrical injuries. We review our burn center's experience with electrical injuries related to fishing activities during the last four years. We retrospectively collected data on patients with electrical burns related to fishing activities between January 2006, when our burns unit was established, and December 2009. Eight patients with electrical burns were admitted during this period of time, five who sustained the injury while fishing, due to contact of the fishing rod with overhead high-voltage cables and three who were injured during illegal fishing, using electricity to stun the fish. The total burn surface area ranged from 0.5% to 70%. Three of the patients sustained fourth degree burns, while the rest had second and third degree burns. One patient underwent scapulohumeral disarticulation and an above-knee amputation. Two patients had fingers and toes amputated. Latissimus dorsi and anterolateral thigh flaps were used to cover the defects in two cases. Local flaps were employed in other two cases to cover the tissue defects. Two patients died. Fishing-related burns and illegal fishing can lead to serious injuries and death. Copyright © 2010 Elsevier Ltd and ISBI. All rights reserved.

  4. Discrepancies between clinical assessments of sensory function and electrical perceptual thresholds after incomplete chronic cervical spinal cord injury.

    Science.gov (United States)

    Macklin, R A; Brooke, V J; Calabro, F J; Ellaway, P H; Perez, M A

    2016-01-01

    Prospective experimental. To compare sensory function as revealed by light touch and pin prick tests of the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) and the electrical perceptual threshold (EPT) exams in individuals with chronic incomplete cervical spinal cord injury (SCI). Pittsburgh, United States. EPT was tested using cutaneous electrical stimulation (0.5 ms pulse width, 3 Hz) in 32 healthy controls and in 17 participants with SCI over key points on dermatomes C2 to T4 on each side of the body. Light touch and pin prick ISNCSCI scores were tested at the same key dermatomes in SCI participants. In controls, EPT values were higher in older males (1.26±0.2 mA, mean±s.d.) compared with younger males (1.0±0.2 mA) and older females (0.9±0.2 mA), regardless of the dermatome and side tested. Fifteen out of the seventeen SCI participants showed that the level of sensory impairment detected by the EPT was below the level detected by the ISNCSCI (mean=4.5±2.4, range 1-9). The frequency distribution of EPTs was similar to older male controls in dermatomes above but not below the ISNCSCI sensory level. The difference between EPT and ISNCSCI sensory level was negatively correlated with the time post injury. The results show that, in the chronic stage of cervical SCI, the EPT reveals spared sensory function at lower (~5) spinal segments compared with the ISNCSCI sensory exam. It is hence found that the EPT is a sensitive tool to assess recovery of sensory function after chronic SCI.

  5. Power-MOSFET Voltage Regulator

    Science.gov (United States)

    Miller, W. N.; Gray, O. E.

    1982-01-01

    Ninety-six parallel MOSFET devices with two-stage feedback circuit form a high-current dc voltage regulator that also acts as fully-on solid-state switch when fuel-cell out-put falls below regulated voltage. Ripple voltage is less than 20 mV, transient recovery time is less than 50 ms. Parallel MOSFET's act as high-current dc regulator and switch. Regulator can be used wherever large direct currents must be controlled. Can be applied to inverters, industrial furnaces photovoltaic solar generators, dc motors, and electric autos.

  6. Silicone elastomers with aromatic voltage stabilizers

    DEFF Research Database (Denmark)

    A Razak, Aliff Hisyam; Skov, Anne Ladegaard

    elastomers with high relative permittivity and low Young’s modulus in order to increase the actuation performance at a given voltage, but the optimised elastomers often possess relatively low electrical breakdown strength. On the other hand, increasing the electrical breakdown strength of DEs allows...... modifications. In order to increase the electrical breakdown strength of polymers for e.g. the cable industry, additives like aromatic voltage stabilizers are used. Earlier works on using voltage stabilizers in polymers have mainly focused on polyethylene with the purpose of reducing power loss for high voltage...... insulation cables.3–5 As an alternative to utilise additives as voltage stabilizers, grafting aromatic compounds to silicone backbones may overcome the common problem of insolubility of the aromatic voltage stabilizer in the silicone elastomers due to phase separation. Preventing phase separation during...

  7. Numerical evaluation of currents induced in a worker by ELF non-uniform electric fields in high voltage substations and comparison with experimental results.

    Science.gov (United States)

    Tarao, Hiroo; Korpinen, Leena H; Kuisti, Harri A; Hayashi, Noriyuki; Elovaara, Jarmo A; Isaka, Katsuo

    2013-01-01

    An ungrounded human, such as a substation worker, receives contact currents when touching a grounded object in electric fields. In this article, contact currents and internal electric fields induced in the human when exposed to non-uniform electric fields at 50 Hz are numerically calculated. This is done using a realistic human model standing at a distance of 0.1-0.5 m from the grounded conductive object. We found that the relationship between the external electric field strength and the contact current obtained by calculation is in good agreement with previous measurements. Calculated results show that the contact currents largely depend on the distance, and that the induced electric fields in the tissues are proportional to the contact current regardless of the non-uniformity of the external electric field. Therefore, it is concluded that the contact current, rather than the spatial average of the external electric field, is more suitable for evaluating electric field dosimetry of tissues. The maximum induced electric field appears in the spinal cord in the central nervous system tissues, with the induced electric field in the spinal cord approaching the basic restriction (100 mV/m) of the new 2010 International Commission on Non-Ionizing Radiation Protection guidelines for occupational exposure, if the contact current is 0.5 mA. Copyright © 2012 Wiley Periodicals, Inc.

  8. An Autonomic Neuroprosthesis: Noninvasive Electrical Spinal Cord Stimulation Restores Autonomic Cardiovascular Function in Individuals with Spinal Cord Injury.

    Science.gov (United States)

    Phillips, Aaron A; Squair, Jordan W; Sayenko, Dimitry G; Edgerton, V Reggie; Gerasimenko, Yury; Krassioukov, Andrei V

    2018-02-01

    Despite autonomic dysfunction after spinal cord injury (SCI) being the major cause of death and a top health priority, the clinical management options for these conditions are limited to drugs with delayed onset and nonpharmacological interventions with equivocal effectiveness. We tested the capacity of electrical stimulation, applied transcutaneously over the spinal cord, to manage autonomic dysfunction in the form of orthostatic hypotension after SCI. We assessed beat-by-beat blood pressure (BP), stroke volume, and cardiac contractility (dP/dt; Finometer), as well as cerebral blood flow (transcranial Doppler) in 5 individuals with motor-complete SCI (4 cervical, 1 thoracic) during an orthostatic challenge with and without transcutaneous electrical stimulation applied at the TVII level. During the orthostatic challenge, all individuals experienced hypotension characterized by a 37 ± 4 mm Hg decrease in systolic BP, a 52 ± 10% reduction in cardiac contractility, and a 23 ± 6% reduction in cerebral blood flow (all p stimulation completely normalized BP, cardiac contractility, cerebral blood flow, and abrogated all symptoms. Noninvasive transcutaneous electrical spinal cord stimulation may be a viable therapy for restoring autonomic cardiovascular control after SCI.

  9. Hybrid electric vehicle power management system

    Science.gov (United States)

    Bissontz, Jay E.

    2015-08-25

    Level voltage levels/states of charge are maintained among a plurality of high voltage DC electrical storage devices/traction battery packs that are arrayed in series to support operation of a hybrid electric vehicle drive train. Each high voltage DC electrical storage device supports a high voltage power bus, to which at least one controllable load is connected, and at least a first lower voltage level electrical distribution system. The rate of power transfer from the high voltage DC electrical storage devices to the at least first lower voltage electrical distribution system is controlled by DC-DC converters.

  10. Electric power quality analysis methods. Application to voltage dips and harmonic disturbances; Methodes d'analyse de la qualite de l'energie electrique. Application aux creux de tension et a la pollution harmonique

    Energy Technology Data Exchange (ETDEWEB)

    Vanya, Ignatova

    2006-10-15

    The power quality concerns all the actors in the energy domains, that they are network administrators, suppliers, producers, or consumers of electricity. The research work presented in this PhD thesis is situated in the field of the power quality monitoring. Its objective is to introduce new techniques for analysis of power quality problems. There are different methods designed for the analysis of the power quality disturbances. This method reaches very good performances in the voltage dips analysis, as it allows segmenting, classifying and characterising these power quality disturbances. The periodic systems method allows the theoretical study of the generation and the propagation of harmonic disturbances in the network. Finally, the statistical matrix method has the objective to represent statistically electrical signals without loss of important information. (author)

  11. Effects of cycling and/or electrical stimulation on bone mineral density in children with spinal cord injury.

    Science.gov (United States)

    Lauer, R T; Smith, B T; Mulcahey, M J; Betz, R R; Johnston, T E

    2011-08-01

    Randomized clinical trial. To determine the effect of cycling and/or electrical stimulation on hip and knee bone mineral density (BMD) in children with spinal cord injury (SCI). Children's hospital specializing in pediatric SCI. A total of 30 children, aged 5-13 years, with chronic SCI were randomized to one of three interventions: functional electrical stimulation cycling (FESC), passive cycling (PC), and non-cycling, electrically stimulated exercise (ES). Each group exercised for 1 h, three times per week for 6 months at home. The hip, distal femur and proximal tibia BMD were examined via dual-energy X-ray absorptiometry (DXA) pre- and post-intervention. In all, 28 children completed data collection. The FESC group exhibited increases in hip, distal femur and proximal tibia BMD of 32.4, 6.62 and 10.3%, respectively. The PC group exhibited increases at the hip (29.2%), but no change at the distal femur (1.5%) or proximal tibia (-1.0%). The ES group had no change at the hip (-0.24%) and distal femur (3.3%), but a loss at the proximal tibia (-7.06%). There were no differences between groups or within groups over time. Significant negative correlations were found between baseline BMD and the amount of BMD change. Although not achieving statistical significance, hip BMD changes observed were greater than the reported 0.9-10% gains after exercise for children with and without disability. Thus, cycling with and without electrical stimulation may be beneficial for skeletal health in pediatric SCI, but further research is needed with a larger sample size.

  12. Evaluation of PVA biodegradable electric conductive membranes for nerve regeneration in axonotmesis injuries: the rat sciatic nerve animal model.

    Science.gov (United States)

    Ribeiro, Jorge; Caseiro, Ana Rita; Pereira, Tiago; Armada-da-Silva, Paulo Alexandre; Pires, Isabel; Prada, Justina; Amorim, Irina; Leal Reis, Inês; Amado, Sandra; Santos, José Domingos; Bompasso, Simone; Raimondo, Stefania; Varejão, Artur Severo Proença; Geuna, Stefano; Luís, Ana Lúcia; Maurício, Ana Colette

    2017-05-01

    The therapeutic effect of three polyvinyl alcohol (PVA) membranes loaded with electrically conductive materials - carbon nanotubes (PVA-CNTs) and polypyrrole (PVA-PPy) - were tested in vivo for neuro-muscular regeneration after an axonotmesis injury in the rat sciatic nerve. The membranes electrical conductivity measured was 1.5 ± 0.5 × 10(-6) S/m, 579 ± 0.6 × 10(-6) S/m, and 1837.5 ± 0.7 × 10(-6) S/m, respectively. At week-12, a residual motor and nociceptive deficit were present in all treated groups, but at week-12, a better recovery to normal gait pattern of the PVA-CNTs and PVA-PPy treated groups was observed. Morphometrical analysis demonstrated that PVA-CNTs group presented higher myelin thickness and lower g-ratio. The tibialis anterior muscle, in the PVA-PPy and PVA-CNTs groups showed a 9% and 19% increase of average fiber size area and a 5% and 10% increase of the "minimal Feret's diameter," respectively. No inflammation, degeneration, fibrosis or necrosis were detected in lung, liver, kidneys, spleen, and regional lymph nodes and absence of carbon deposits was confirmed with Von Kossa and Masson-Fontana stains. In conclusion, the membranes of PVA-CNTs and PVA-PPy are biocompatible and have electrical conductivity. The higher electrical conductivity measured in PVA-CNTs membrane might be responsible for the positive results on maturation of myelinated fibers. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1267-1280, 2017. © 2017 Wiley Periodicals, Inc.

  13. Increase in the number of distributed power generation installations in electricity distribution grids - Simulation in a 400 V low-voltage network; Zunahme der dezentralen Energieerzeugungsanlagen in elektrischen Verteilnetzen: Simulationen im 400 V Niederspannungsnetz des ewz

    Energy Technology Data Exchange (ETDEWEB)

    Hoeckel, M.; Luechinger, P.

    2003-07-01

    This is the sixth part of a ten-part final report for the Swiss Federal Office of Energy (SFOE) on a project that looked into potential problems relating to the Swiss electricity distribution grid with respect to the increasing number of distributed power generation facilities being put into service. The identification of special conditions for the grid's operation and future development that take increasing decentralised power production into account are discussed. The results of the project activities encompass the analysis and evaluation of various problem areas associated with planning and management of the grid during normal operation and periods of malfunction, as well as required modifications to safety systems and grid configurations. This fifth appendix to the main report presents and discusses the results of simulations made on the basis of the real-life 400 V low-voltage distribution network operated by the public utilities of the City of Zurich, Switzerland. This comprehensive appendix describes the simulation methods used and the basic characteristics of low-voltage networks and distributed generation facilities. The 6 simulation variants used are also described. The results of the simulations are presented in graphical form and provide profiles of voltage and current, active and reactive power and further mains characteristics for varying load conditions. Also, short-circuit simulations and harmonics analysis are discussed.

  14. Irreversibility in room temperature current–voltage characteristics of NiFe{sub 2}O{sub 4} nanoparticles: A signature of electrical memory effect

    Energy Technology Data Exchange (ETDEWEB)

    Dey, P., E-mail: pujaiitkgp2007@gmail.com [Department of Physics, Kazi Nazrul University, Asansol, W.B. 713340 (India); Debnath, Rajesh; Singh, Swati; Mandal, S.K. [Department of Physics, National Institute of Technology Agartala, Tripura 799046 (India); Roy, J.N. [Department of Physics, Kazi Nazrul University, Asansol, W.B. 713340 (India); Department of Physics, National Institute of Technology Agartala, Tripura 799046 (India)

    2017-01-01

    Room temperature I–V characteristics study, both in presence and absence of magnetic field (1800 Oe), has been performed on NiFe{sub 2}O{sub 4} nanoparticles, having different particle size (φ~14, 21 and 31 nm). Our experiments on these nanoparticles provide evidences for: (1) electrical irreversibility or hysteretic behaviour; (2) positive magnetoresistance and (3) magnetic field dependent electrical irreversibility or hysteresis in the sample. “Hysteretic” nature of I–V curve reveals the existence of electrical memory effect in the sample. Significantly, such hysteresis has been found to be tuned by magnetic field. In order to explain the observed electrical irreversibility, we have proposed a phenomenological model on the light of induced polarization in the sample. Both the positive magnetoresistance and the observed magnetic field dependence of electrical irreversibility have been explained through magnetostriction phenomenon. Interestingly, such effects are found to get reduced with increasing particle size. For NiFe{sub 2}O{sub 4} nanoparticles having φ=31 nm, we did not observe any irreversibility effect. This feature has been attributed to the enhanced grain surface effect that in turn gives rise to the residual polarization and hence electrical memory effect in NiFe{sub 2}O{sub 4} nanoparticles, having small nanoscopic particle size. - Highlights: • I-V characteristics study of NiFe{sub 2}O{sub 4} nanoparticles with varying particle sizes. • Experiments evident electrical hysteretic behaviour, i.e., electrical memory effect. • Magnetic field dependent electrical irreversibility is due to magnetostriction. • A phenomenological model has been proposed on the light of induced polarization. • Such electrical irreversibility decreases with increasing particle sizes.

  15. Hybrid functional electrical stimulation exercise training alters the relationship between spinal cord injury level and aerobic capacity.

    Science.gov (United States)

    Taylor, J Andrew; Picard, Glen; Porter, Aidan; Morse, Leslie R; Pronovost, Meghan F; Deley, Gaelle

    2014-11-01

    To test the hypothesis that hybrid functional electrical stimulation (FES) row training would improve aerobic capacity but that it would remain strongly linked to level of spinal cord lesion because of limited maximal ventilation. Longitudinal before-after trial of 6 months of FES row training. Exercise for persons with disabilities program in a hospitaL. Volunteers (N=14; age range, 21-63y) with complete spinal cord injury (SCI) (T3-11) who are >2 years postinjury. Six months of FES row training preceded by a variable period of FES strength training. Peak aerobic capacity and peak exercise ventilation before and after 6 months of FES row training. FES row training significantly increased peak aerobic capacity and peak minute ventilation (both Pinjury and peak minute ventilation was comparable before and after FES row training (adjusted R(2)=.38 vs .32, both Pinjury. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  16. The effects of functional electrical stimulation leg cycle ergometry training on arterial compliance in individuals with spinal cord injury.

    Science.gov (United States)

    Zbogar, D; Eng, J J; Krassioukov, A V; Scott, J M; Esch, B T A; Warburton, D E R

    2008-11-01

    A prospective intervention of functional electrical stimulation leg cycle ergometry (FES-LCE) of four women with spinal cord injury (SCI). To evaluate the effect of FES-LCE training on arterial compliance in individuals with chronic SCI of traumatic origin. Tertiary rehabilitation center in Canada. Large and small artery compliance were measured at the radial artery before and after a 3-month training program using FES-LCE. There was no significant change in large artery compliance after FES-LCE (16.0+/-4.2 to 16.8+/-6.1 ml mm Hg(-1) x 10, P=NS). There was a marked (63%) increase in small artery compliance after the FES training program (4.2+/-1.8 to 6.9+/-3.2 ml mm Hg(-1) x 100, P<0.05). It appears that FES-LCE is effective in improving small artery compliance in females with SCI.

  17. Brain-computer interface driven functional electrical stimulation system for overground walking in spinal cord injury participant.

    Science.gov (United States)

    King, Christine E; Wang, Po T; McCrimmon, Colin M; Chou, Cathy C Y; Do, An H; Nenadic, Zoran

    2014-01-01

    The current treatment for ambulation after spinal cord injury (SCI) is to substitute the lost behavior with a wheelchair; however, this can result in many co-morbidities. Thus, novel solutions for the restoration of walking, such as brain-computer interfaces (BCI) and functional electrical stimulation (FES) devices, have been sought. This study reports on the first electroencephalogram (EEG) based BCI-FES system for overground walking, and its performance assessment in an individual with paraplegia due to SCI. The results revealed that the participant was able to purposefully operate the system continuously in real time. If tested in a larger population of SCI individuals, this system may pave the way for the restoration of overground walking after SCI.

  18. A system to integrate electrical stimulation with robotically controlled treadmill training to rehabilitate stepping after spinal cord injury.

    Science.gov (United States)

    Chao, Tekang; Askari, Sina; De Leon, Ray; Won, Deborah

    2012-09-01

    A functional electrical stimulation (FES) system was engineered to integrate information from a robotically controlled position during stepping in order to time stimulation to continuous gait information in a rodent model of spinal cord injury (SCI). In contrast to conventional FES systems which have a fixed timing pattern relative to gait cycle onset (i.e., toe off/heel off or paw contact/heel strike), this system allows adaptation of stimulation to a robotically controlled position. Rationale for the system design is presented along with bench-test results verifying the timing of the stimulation with respect to hindlimb position. This robotically timed FES system will enable studies investigating the capability of this FES therapy to encourage rehabilitation by way of spinal plasticity.

  19. Endurance neuromuscular electrical stimulation training improves skeletal muscle oxidative capacity in individuals with motor-complete spinal cord injury.

    Science.gov (United States)

    Erickson, Melissa L; Ryan, Terence E; Backus, Deborah; McCully, Kevin K

    2017-05-01

    Spinal cord injury (SCI) results in skeletal muscle atrophy, increases in intramuscular fat, and reductions in skeletal muscle oxidative capacity. Endurance training elicited with neuromuscular electrical stimulation (NMES) may reverse these changes and lead to improvement in muscle metabolic health. Fourteen participants with complete SCI performed 16 weeks of home-based endurance NMES training of knee extensor muscles. Skeletal muscle oxidative capacity, muscle composition, and blood metabolic and lipid profiles were assessed pre- and post-training. There was an increase in number of contractions performed throughout the duration of training. The average improvement in skeletal muscle oxidative capacity was 119%, ranging from -14% to 387% (P = 0.019). There were no changes in muscle composition or blood metabolic and lipid profiles. Endurance training improved skeletal muscle oxidative capacity, but endurance NMES of knee extensor muscles did not change blood metabolic and lipid profiles. Muscle Nerve 55: 669-675, 2017. © 2016 Wiley Periodicals, Inc.

  20. Functional electrical stimulation-assisted walking for persons with incomplete spinal injuries

    DEFF Research Database (Denmark)

    Ladouceur, M.; Barbeau, H.

    2000-01-01

    This study investigated the changes in maximal overground walking speed (MOWS) that occurred during; walking training with a functional electrical stimulation (FES) orthosis by chronic spinal cord injured persons with incomplete motor function loss. The average walking: speed over a distance of 10...

  1. Modeling of skin cooling, blood flow, and optical properties in wounds created by electrical shock

    Science.gov (United States)

    Nguyen, Thu T. A.; Shupp, Jeffrey W.; Moffatt, Lauren T.; Jordan, Marion H.; Jeng, James C.; Ramella-Roman, Jessica C.

    2012-02-01

    High voltage electrical injuries may lead to irreversible tissue damage or even death. Research on tissue injury following high voltage shock is needed and may yield stage-appropriate therapy to reduce amputation rate. One of the mechanisms by which electricity damages tissue is through Joule heating, with subsequent protein denaturation. Previous studies have shown that blood flow had a significant effect on the cooling rate of heated subcutaneous tissue. To assess the thermal damage in tissue, this study focused on monitoring changes of temperature and optical properties of skin next to high voltage wounds. The burns were created between left fore limb and right hind limb extremities of adult male Sprague-Dawley rats by a 1000VDC delivery shock system. A thermal camera was utilized to record temperature variation during the exposure. The experimental results were then validated using a thermal-electric finite element model (FEM).

  2. Investigation of disorder and its effect on electrical transport in electrochemically doped polymer devices by current-voltage and impedance spectroscopy

    Science.gov (United States)

    Rahman Khan, Motiur; Anjaneyulu, P.; Koteswara Rao, K. S. R.; Menon, R.

    2017-03-01

    We report on the analysis of temperature-dependent current-voltage characteristics and impedance measurements of electrochemically doped poly(3-methylthiophene) devices at different doping levels. The extent of doping is carefully tailored such that only the bulk-limited transport mechanism prevails. A transition from exponentially distributed trap-limited transport to trap-free space-charge-limited current is observed in current-voltage conduction upon increasing the doping. The obtained trap densities (3.2  ×  1016 cm-3 and 8.6  ×  1015 cm-3) and trap energies (31.7 meV and 16.6 meV) for different devices signify the variation in disorder with doping, which is later supported by impedance measurements. Impedance-frequency data for various devices can not be explained using the parallel resistance-capacitance (RC) model in the equivalent circuit. However, this was established by incorporating a constant phase element Q (CPE) instead of the capacitance parameter. It should be emphasized that low doping devices in particular are best simulated with two CPE elements, while the data related to other devices are fitted well with a single CPE element. It is also observed from evaluated circuit parameters that the spatial inhomogeneity and disorder are the cause of variability in different samples, which has an excellent correlation with the temperature-dependent current-voltage characteristics.

  3. Electro-optical voltage transformer

    Science.gov (United States)

    Xu, Yan; Ye, Miaoyuan; Cui, Ying

    1999-02-01

    The work introduces an optical fiber voltage transformer based on the Pockels effect. The transformer is different from a conventional electric-magnetic voltage transformer. A crystal BGO is used as sensor that is sealed in SF6 gas container; the measured signal is transferred by optical fiber in the Electro-Optical Voltage Transformer (EOVT). The principles and composition of EOVT is described here. The system consists of three parts: capacitive divider, optical sensor and electronics module. According to the analysis of factors that influence on the accuracy of measurement, the main ones, temperature and pressure of SF6, are corrected by means of signal digital process. The performances of 110kV EOVT were tested. The results show that the accuracy of EOVT could achieve 0.5 percent. Compared to a conventional electric-magnetic voltage transformer, the advantages of 110kV EOVT are higher accuracy, low cost, small volume, excellent dynamic characteristics and immunity from electromagnetic interference. In particular the low voltage is effectively isolated from the high voltage by means of the optical fiber.

  4. Scaling law for voltage-current curve of a superconductor tape with a power-law dependence of electric field on a magnetic-field-dependent sheet current density

    Science.gov (United States)

    Li, Shuo; Chen, Du-Xing

    2017-07-01

    Systematic theoretical study on the voltage (V) vs. current (I) curves of high-Tc superconductor (HTS) thin tapes has not been done till now, although their measurements are frequently used for determining critical current Ic at electric field E ≡ V /lv =Ec =10-4 V/m, lv being the voltage tap distance. On the other hand, it is well recognized that such tapes obey a power-law dependence of local electric field on local sheet current density with a Kim-model critical sheet current density, from which the V vs. I curve may be calculated as a function of current ramp rate R. Such calculations are carried out in the present work with a scaling law deduced, which states that if E/Ec vs. I/Ic is a solution at given apparent power-law exponent na and R/Ec, then this R/Ec multiplied by a constant C leads to another solution with E/Ec and I/Ic multiplied by C and C1/na , respectively. In the help of the scaling law, condition-dependent V vs. I may be studied systematically and completely based on a limited amount of numerical computations and V - I curve measurements may be performed under properly controlled conditions to become a more powerful tool for HTS research.

  5. Changes in the expression of voltage-gated sodium channels Nav1.3, Nav1.7, Nav1.8, and Nav1.9 in rat trigeminal ganglia following chronic constriction injury.

    Science.gov (United States)

    Xu, Wenhua; Zhang, Jun; Wang, Yuanyin; Wang, Liecheng; Wang, Xuxia

    2016-08-17

    Voltage-gated sodium channels (VGSCs), especially the tetrodotoxin-sensitive Nav1.3 and Nav1.7, and the tetrodotoxin-resistant Nav1.8 and Nav1.9, have been implicated in acute and chronic neuropathic pain. The aim of this study was to investigate the expression of VGSC Nav1.3, Nav1.7, Nav1.8, and Nav1.9 after nerve injury and their roles in the development of trigeminal neuralgia (TN). We used the infraorbital nerve-chronic constriction injury model of TN in the rat. The time course of changes in the mechanical pain threshold was examined. In addition, real-time PCR and double immunofluorescence staining of VGSC α subunits were used to evaluate messenger RNA and protein expression, respectively, in the trigeminal ganglion. Behavioral tests showed that the mechanical pain threshold decreased significantly 4-42 days after surgery and reached the lowest observed value by day 12. Compared with sham-operated controls, we found that trigeminal ganglion in rats subjected to an infraorbital nerve-chronic constriction injury showed upregulation of Nav1.3 and downregulation of Nav1.7, Nav1.8, and Nav1.9 messenger RNA and protein levels. Our findings suggest that VGSC may participate in the regulation of TN.

  6. VOLTAGE REGULATORS OF SYNCHRONOUS GENERATORS

    OpenAIRE

    Grigorash O. V.; Korzenkov P. G.; Popuchieva M. A.

    2015-01-01

    Synchronous generators are the primary source of electrical power autonomous electrosupply systems, including backup systems. They are also used in a structure of rotating electricity converters and are widely used in renewable energy as part of wind power plants of small, mini and micro hydroelectric plants. Increasing the speed and the accuracy of the system of the voltage regulation of synchronous generators is possible due to the development of combined systems containing more stabilizers...

  7. Monitoring of spasticity and functional ability in individuals with incomplete spinal cord injury with a functional electrical stimulation cycling system.

    Science.gov (United States)

    Reichenfelser, Werner; Hackl, Harald; Hufgard, Josef; Kastner, Josef; Gstaltner, Karin; Gföhler, Margit

    2012-05-01

    The aim of this study was to investigate the integration of motor function and spasticity assessment of individuals with spinal cord injury into cycling therapy. Twenty-three participants with incomplete spinal cord injury performed 18 training sessions (standard deviation (SD) 14) on an instrumented tricycle combined with functional electrical stimulation. Each therapy session included a power output test to assess the participants' ability to pedal actively and a spasticity test routine that measures the legs' resistance to the pedalling motion. In addition, the required time for the therapy phases was monitored. The results of the power output test showed a monthly increase in power output of 4.4 W (SD 13.7) at 30 rpm and 18.2 W (SD 23.9) at 60 rpm. The results of the spasticity assessment indicate a 12.2 W (SD 9.7) reduction in resistance at 60 rpm after the FES training for the subject group with spasticity. In clinical use over a time-period of 2 years this combined form of therapy and motor function assessment was well accepted by participants. The active power output test and the spasticity test routine offered a proper tool to monitor participants' progress in functional rehabilitation and changes in spasticity.

  8. Functional electrical stimulation cycling improves body composition, metabolic and neural factors in persons with spinal cord injury.

    Science.gov (United States)

    Griffin, L; Decker, M J; Hwang, J Y; Wang, B; Kitchen, K; Ding, Z; Ivy, J L

    2009-08-01

    Persons with spinal cord injury (SCI) are at a heightened risk of developing type II diabetes and cardiovascular disease. The purpose of this investigation was to conduct an analysis of metabolic, body composition, and neurological factors before and after 10 weeks of functional electrical stimulation (FES) cycling in persons with SCI. Eighteen individuals with SCI received FES cycling 2-3 times per week for 10 weeks. Body composition was analyzed by dual X-ray absorptiometry. The American Spinal Injury Association (ASIA) neurological classification of SCI test battery was used to assess motor and sensory function. An oral glucose tolerance (OGTT) and insulin-response test was performed to assess blood glucose control. Additional metabolic variables including plasma cholesterol (total-C, HDL-C, LDL-C), triglyceride, and inflammatory markers (IL-6, TNF-alpha, and CRP) were also measured. Total FES cycling power and work done increased with training. Lean muscle mass also increased, whereas, bone and adipose mass did not change. The ASIA motor and sensory scores for the lower extremity significantly increased with training. Blood glucose and insulin levels were lower following the OGTT after 10 weeks of training. Triglyceride levels did not change following training. However, levels of IL-6, TNF-alpha, and CRP were all significantly reduced.

  9. Abdominal functional electrical stimulation to improve respiratory function after spinal cord injury: a systematic review and meta-analysis.

    Science.gov (United States)

    McCaughey, E J; Borotkanics, R J; Gollee, H; Folz, R J; McLachlan, A J

    2016-09-01

    Abdominal functional electrical stimulation (abdominal FES) is the application of a train of electrical pulses to the abdominal muscles, causing them to contract. Abdominal FES has been used as a neuroprosthesis to acutely augment respiratory function and as a rehabilitation tool to achieve a chronic increase in respiratory function after abdominal FES training, primarily focusing on patients with spinal cord injury (SCI). This study aimed to review the evidence surrounding the use of abdominal FES to improve respiratory function in both an acute and chronic manner after SCI. A systematic search was performed on PubMed, with studies included if they applied abdominal FES to improve respiratory function in patients with SCI. Fourteen studies met the inclusion criteria (10 acute and 4 chronic). Low participant numbers and heterogeneity across studies reduced the power of the meta-analysis. Despite this, abdominal FES was found to cause a significant acute improvement in cough peak flow, whereas forced exhaled volume in 1 s approached significance. A significant chronic increase in unassisted vital capacity, forced vital capacity and peak expiratory flow was found after abdominal FES training compared with baseline. This systematic review suggests that abdominal FES is an effective technique for improving respiratory function in both an acute and chronic manner after SCI. However, further randomised controlled trials, with larger participant numbers and standardised protocols, are needed to fully establish the clinical efficacy of this technique.

  10. Effect of applied voltage, duration and repetition frequency of RF pulses for pain relief on temperature spikes and electrical field: a computer modelling study.

    Science.gov (United States)

    Ewertowska, Elżbieta; Mercadal, Borja; Muñoz, Víctor; Ivorra, Antoni; Trujillo, Macarena; Berjano, Enrique

    2018-02-01

    The thermal and electrical effects of pulsed radiofrequency (PRF) for pain relief can be controlled by modifying the characteristics of the RF pulses applied. Our goal was to evaluate the influence of such modifications on the thermal and electric performance in tissue. A computational model was developed to compare the temperature and electric field time courses in tissue between a standard clinical protocol (45 V pulses, 20 ms duration, 2 Hz repetition frequency) and a new protocol (55 V pulses, 5 ms duration, 5 Hz repetition frequency) with a higher applied electric field but a smaller impact on temperature alterations in tissue. The effect of including a temperature controller was assessed. Complementarily, an agar-based experimental model was developed to validate the methodology employed in the computer modelling. The new protocol increased the electric field magnitude reached in the tissue by around +20%, without increasing the temperature. The temperature controller was found to be the fundamental factor in avoiding thermal damage to the tissue and reduced the total number of pulses delivered by around 67%. The experimental results matched moderately well with those obtained from a computer model built especially to mimic the experimental conditions. For the same delivered energy, the new protocol significantly increases the magnitude of the applied electric field, which may be the reason why it is clinically more effective in achieving pain relief.

  11. Altered contractile properties of the quadriceps muscle in people with spinal cord injury following functional electrical stimulated cycle training.

    Science.gov (United States)

    Gerrits, H L; de Haan, A; Sargeant, A J; Dallmeijer, A; Hopman, M T

    2000-04-01

    A longitudinal training study. To assess if contractile speed and fatigability of paralysed quadriceps muscles in individuals with spinal cord injury (SCI) can be altered by functional electrical stimulation leg cycle ergometry (FES-LCE) training. The Sint Maartenskliniek rehabilitation centre and the University of Nijmegen, Nijmegen, the Netherlands. Contractile properties of the quadriceps muscle were studied in seven people with motor-complete SCI who participated in a FES-LCE training program. Subjects trained for 30 min, three times per week for 6 weeks. Contractile speed and fatigue characteristics of electrically stimulated isometric contractions were compared before and after 6 weeks of FES-LCE. Fatigue resistance improved following FES-LCE training as indicated by the higher forces maintained in response to repetitive electrical stimulation. In contrast with an improved fatigue resistance, the maximal rate of force rise was unaffected, the speed of relaxation increased and the fusion of a 10 Hz force signal decreased. Furthermore, the force-frequency relationship shifted to the right at low stimulation frequencies, indicated by a decline in the ratio of 1 and 100 Hz force responses as well as the ratio of 10 and 100 Hz force responses. FES-LCE training can change the physiological properties of the quadriceps muscle in people with SCI. Even after a short period of training, the stimulated muscles become more resistant to fatigue. Furthermore, the increased speed of relaxation and associated decreased fusion and altered force-frequency relationship following training may be related to adaptations in the calcium handling processes, which reflect an early response of long-term disused muscles.

  12. Emergency Department Triage of Traumatic Head Injury Using a Brain Electrical Activity Biomarker: A Multisite Prospective Observational Validation Trial.

    Science.gov (United States)

    Hanley, Daniel; Prichep, Leslie S; Bazarian, Jeffrey; Huff, J Stephen; Naunheim, Rosanne; Garrett, John; Jones, Elizabeth B; Wright, David W; O'Neill, John; Badjatia, Neeraj; Gandhi, Dheeraj; Curley, Kenneth C; Chiacchierini, Richard; O'Neil, Brian; Hack, Dallas C

    2017-05-01

    A brain electrical activity biomarker for identifying traumatic brain injury (TBI) in emergency department (ED) patients presenting with high Glasgow Coma Scale (GCS) after sustaining a head injury has shown promise for objective, rapid triage. The main objective of this study was to prospectively evaluate the efficacy of an automated classification algorithm to determine the likelihood of being computed tomography (CT) positive, in high-functioning TBI patients in the acute state. Adult patients admitted to the ED for evaluation within 72 hours of sustaining a closed head injury with GCS 12 to 15 were candidates for study. A total of 720 patients (18-85 years) meeting inclusion/exclusion criteria were enrolled in this observational, prospective validation trial, at 11 U.S. EDs. GCS was 15 in 97%, with the first and third quartiles being 15 (interquartile range = 0) in the study population at the time of the evaluation. Standard clinical evaluations were conducted and 5 to 10 minutes of electroencephalogram (EEG) was acquired from frontal and frontal-temporal scalp locations. Using an a priori derived EEG-based classification algorithm developed on an independent population and applied to this validation population prospectively, the likelihood of each subject being CT+ was determined, and performance metrics were computed relative to adjudicated CT findings. Sensitivity of the binary classifier (likely CT+ or CT-) was 92.3% (95% confidence interval [CI] = 87.8%-95.5%) for detection of any intracranial injury visible on CT (CT+), with specificity of 51.6% (95% CI = 48.1%-55.1%) and negative predictive value (NPV) of 96.0% (95% CI = 93.2%-97.9%). Using ternary classification (likely CT+, equivocal, likely CT-) demonstrated enhanced sensitivity to traumatic hematomas (≥1 mL of blood), 98.6% (95% CI = 92.6%-100.0%), and NPV of 98.2% (95% CI = 95.5%-99.5%). Using an EEG-based biomarker high accuracy of predicting the likelihood of being CT+ was obtained, with

  13. Distribution of internal pressure around bony prominences: implications to deep tissue injury and effectiveness of intermittent electrical stimulation.

    Science.gov (United States)

    Solis, Leandro R; Liggins, Adrian; Uwiera, Richard R E; Poppe, Niek; Pehowich, Enid; Seres, Peter; Thompson, Richard B; Mushahwar, Vivian K

    2012-08-01

    The overall goal of this project is to develop interventions for the prevention of deep tissue injury (DTI), a form of pressure ulcers that originates in deep tissue around bony prominences. The present study focused on: (1) obtaining detailed measures of the distribution of pressure experienced by tissue around the ischial tuberosities, and (2) investigating the effectiveness of intermittent electrical stimulation (IES), a novel strategy for the prevention of DTI, in alleviating pressure in regions at risk of breakdown due to sustained loading. The experiments were conducted in adult pigs. Five animals had intact spinal cords and healthy muscles and one had a spinal cord injury that led to substantial muscle atrophy at the time of the experiment. A force-controlled servomotor was used to load the region of the buttocks to levels corresponding to 25%, 50% or 75% of each animal's body weight. A pressure transducer embedded in a catheter was advanced into the tissue to measure pressure along a three dimensional grid around the ischial tuberosity of one hind leg. For all levels of external loading in intact animals, average peak internal pressure was 2.01 ± 0.08 times larger than the maximal interfacial pressure measured at the level of the skin. In the animal with spinal cord injury, similar absolute values of internal pressure as that in intact animals were recorded, but the substantial muscle atrophy produced larger maximal interfacial pressures. Average peak internal pressure in this animal was 1.43 ± 0.055 times larger than the maximal interfacial pressure. Peak internal pressure was localized within a ±2 cm region medio-laterally and dorso-ventrally from the bone in intact animals and ±1 cm in the animal with spinal cord injury. IES significantly redistributed internal pressure, shifting the peak values away from the bone in spinally intact and injured animals. These findings provide critical information regarding the relationship between internal and

  14. [Cardiocirculatory arrest caused by electric shock: importance of semi-automatic defibrillator].

    Science.gov (United States)

    Siah, S; Fouadi, F E; Ababou, K; Ihrai, I; Drissi, N K

    2011-03-31

    Accidental electrical burn injuries are serious because they can cause death by cardiocirculatory arrest. Cardiocirculatory arrest induced by low-voltage current is generally due to ventricular fibrillation, and the prognosis is fairly good if the survival chain is efficient. It is necessary to give priority to early defibrillation using an automated external defibrillator. Early defibrillation can immediately restore spontaneous circulation.

  15. High-voltage engineering and testing

    CERN Document Server

    Ryan, Hugh M

    2013-01-01

    This 3rd edition of High Voltage Engineering Testing describes strategic developments in the field and reflects on how they can best be managed. All the key components of high voltage and distribution systems are covered including electric power networks, UHV and HV. Distribution systems including HVDC and power electronic systems are also considered.

  16. High Voltage Seismic Generator

    Science.gov (United States)

    Bogacz, Adrian; Pala, Damian; Knafel, Marcin

    2015-04-01

    This contribution describes the preliminary result of annual cooperation of three student research groups from AGH UST in Krakow, Poland. The aim of this cooperation was to develop and construct a high voltage seismic wave generator. Constructed device uses a high-energy electrical discharge to generate seismic wave in ground. This type of device can be applied in several different methods of seismic measurement, but because of its limited power it is mainly dedicated for engineering geophysics. The source operates on a basic physical principles. The energy is stored in capacitor bank, which is charged by two stage low to high voltage converter. Stored energy is then released in very short time through high voltage thyristor in spark gap. The whole appliance is powered from li-ion battery and controlled by ATmega microcontroller. It is possible to construct larger and more powerful device. In this contribution the structure of device with technical specifications is resented. As a part of the investigation the prototype was built and series of experiments conducted. System parameter was measured, on this basis specification of elements for the final device were chosen. First stage of the project was successful. It was possible to efficiently generate seismic waves with constructed device. Then the field test was conducted. Spark gap wasplaced in shallowborehole(0.5 m) filled with salt water. Geophones were placed on the ground in straight line. The comparison of signal registered with hammer source and sparker source was made. The results of the test measurements are presented and discussed. Analysis of the collected data shows that characteristic of generated seismic signal is very promising, thus confirms possibility of practical application of the new high voltage generator. The biggest advantage of presented device after signal characteristics is its size which is 0.5 x 0.25 x 0.2 m and weight approximately 7 kg. This features with small li-ion battery makes

  17. CLINICAL STUDY OF ELECTRICAL BURNS AMONG ALL BURNS CASES- 3 YEARS’ EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Nagabathula Durga Prasad

    2017-08-01

    Full Text Available BACKGROUND With the advances in technology, electrical injuries are becoming more common and are the leading cause of work-related traumatic death. One third of all electrical traumas and most high-voltage injuries are job related and more than 50% of these injuries result from power line contact. The management of the major burn injury represents a significant challenge to every member of the burns team. Most of electrical burns present with gangrene of toes and limbs with eschar over body parts. Their presentation is mostly due to contact with high-voltage electricity at their work places. MATERIALS AND METHODS A retrospective study was made to study the clinico-social profile of patients suffering electric burns admitted into Department of General Surgery. RESULTS 92 cases were evaluated and studied. Majority of patients developed gangrene of limbs and toes. Amputations and skin grafting was done. Most patients who suffered electric burns were males of age group 21 to 40 years. All cases are accidental and mostly occurred at work places. Most electric burns are high-voltage based and caused deep burns. Major complications like acute renal failure and septicaemia were encountered. Most of them suffered 16 to 30% burns. Most commonly isolated organism from wounds is pseudomonas. Most of them suffered a hospital stay of 1 to 2 months. CONCLUSION Electric burns are a burden to the society. Prevention is the best way to deal with them. Electricity-based employees have to be trained properly regarding safety measures to be taken. General education of public regarding safety measures can prevent electrical burn injuries.

  18. Power electronics as a suitable smart grid solution for electric-powered vehicles and low voltage grids; Leistungselektronik als serientaugliche SmartGrid Loesung fuer Elektrofahrzeuge und Niederspannungsnetze

    Energy Technology Data Exchange (ETDEWEB)

    Piepenbrink, Andreas [E3/DC GmbH, Osnabrueck (Germany); Vetter, Thomas; Speer, Rolf [Aradex AG, Lorch (Germany)

    2010-07-01

    This paper derives the basic model equations and economic functions for energy storage systems in a grid connected photovoltaic system. To maximize the self consumption of households, the charge and discharge strategy of the battery is tested as an optimal mix of net and photovoltaic power with respect to maximum financial output for the customer. A timer series comparison of electrical power for seasonal operation as well as the financial battery return of investment for the next years is derived. An electric car is considered in the simulation model as mobile and backup battery at home and the associated central power electronics architecture is derived. (orig.)

  19. Cooling of electrically insulated high voltage electrodes down to 30 mK Kühlung von elektrisch isolierten Hochspannungselektroden bis 30 mK

    CERN Document Server

    Eisel, Thomas; Bremer, J

    2011-01-01

    The Antimatter Experiment: Gravity, Interferometry, Spectroscopy (AEGIS) at the European Organization for Nuclear Research (CERN) is an experiment investigating the influence of earth’s gravitational force upon antimatter. To perform precise measurements the antimatter needs to be cooled to a temperature of 100 mK. This will be done in a Penning trap, formed by several electrodes, which are charged with several kV and have to be individually electrically insulated. The trap is thermally linked to a mixing chamber of a 3He-4He dilution refrigerator. Two link designs are examined, the Rod design and the Sandwich design. The Rod design electrically connects a single electrode with a heat exchanger, immersed in the helium of the mixing chamber, by a copper pin. An alumina ring and the helium electrically insulate the Rod design. The Sandwich uses an electrically insulating sapphire plate sandwiched between the electrode and the mixing chamber. Indium layers on the sapphire plate are applied to improve the ther...

  20. Study of protection devices against the effects of electric discharges inside a very high voltage generator: the Vivitron accelerator; Etude de dispositifs de protection contre les effets des decharges electriques au sein d`un generateur de tres haute tension: l`accelerateur Vivitron

    Energy Technology Data Exchange (ETDEWEB)

    Nolot, E.

    1996-10-31

    The Vivitron tandem is a large electrostatic accelerator comprising a Van de Graaff generator designed to reach terminal voltages of around 30 MV. The machine is limited at rather lower nominal voltages (about 20 MV) due to the sensitivity of the insulating column structure to transient overvoltages. These are induced by electrical discharges in compressed SF{sub 6}. This thesis first aims at analysing the fundamental reasons of electrical discharges in order to limit the probability of their occurrence. Then we simulate the transient overvoltages induced and present some improvements which may lead to a stable behaviour of the Vivitron at nominal voltages higher than 20 MV. Initially we deduce discharge onset voltages and actual breakdown field limitations in the different gap geometries from analysis of possible breakdown mechanisms in compressed SF{sub 6}. In a second part, some electrical characteristics of the insulating column structure are measured at high voltage. Fast rising oscillating waves induced by sparking in the Vivitron, along with the associated energies,are determined in the third part. The last part deals with new surge protections of the insulating column structure. Spark gaps with precise onset voltage and optimized shielding electrodes are discussed. ZnO-based varistors designed for operation at very high fields have also been developed in order to reduce transient overvoltage values. (author). 122 refs.

  1. A randomized trial of functional electrical stimulation for walking in incomplete spinal cord injury: Effects on walking competency.

    Science.gov (United States)

    Kapadia, Naaz; Masani, Kei; Catharine Craven, B; Giangregorio, Lora M; Hitzig, Sander L; Richards, Kieva; Popovic, Milos R

    2014-09-01

    Multi-channel surface functional electrical stimulation (FES) for walking has been used to improve voluntary walking and balance in individuals with spinal cord injury (SCI). To investigate short- and long-term benefits of 16 weeks of thrice-weekly FES-assisted walking program, while ambulating on a body weight support treadmill and harness system, versus a non-FES exercise program, on improvements in gait and balance in individuals with chronic incomplete traumatic SCI, in a randomized controlled trial design. Individuals with traumatic and chronic (≥18 months) motor incomplete SCI (level C2 to T12, American Spinal Cord Injury Association Impairment Scale C or D) were recruited from an outpatient SCI rehabilitation hospital, and randomized to FES-assisted walking therapy (intervention group) or aerobic and resistance training program (control group). Outcomes were assessed at baseline, and after 4, 6, and 12 months. Gait, balance, spasticity, and functional measures were collected. Spinal cord independence measure (SCIM) mobility sub-score improved over time in the intervention group compared with the control group (baseline/12 months: 17.27/21.33 vs. 19.09/17.36, respectively). On all other outcome measures the intervention and control groups had similar improvements. Irrespective of group allocation walking speed, endurance, and balance during ambulation all improved upon completion of therapy, and majority of participants retained these gains at long-term follow-ups. Task-oriented training improves walking ability in individuals with incomplete SCI, even in the chronic stage. Further randomized controlled trials, involving a large number of participants are needed, to verify if FES-assisted treadmill training is superior to aerobic and strength training.

  2. Simple flaps for reconstruction of pediatric scalp defects after electrical burn

    Directory of Open Access Journals (Sweden)

    Makboul Mohamed

    2013-08-01

    Full Text Available 【Abstract】 Objective: To analyze the management of high-voltage electrical burn injury of the scalp in our hospital. Methods: This study involved 10 patients who suf-fered from high-voltage electrical burn injury of the scalp. Scalp reconstruction was done by different modalities ac-cording to the size and location of the defect. Results: Complete flap viability was achieved in all the cases. We had one case of gapped wound which was managed only by dressing. Widening of the scar was found in 2 cases. Conclusion: Rotation, advancement and transposi-tion scalp flaps are used for reconstructing scalp defects caused by electrical burn. The choice of ideal flaps for re-construction depends upon the size and site of scalp defect. Key words: Burns, electric; Scalp; Reconstructive surgical procedures; Surgical flaps; Skull

  3. Alternative methodology for the margin determination of voltage stability in electrical power systems. Economical and technical impacts; Metodologia alternativa para a determinacao da margem de estabilidade de tensao em sistemas eletricos de potencia - impactos tecnicos e economicos

    Energy Technology Data Exchange (ETDEWEB)

    Cortez, Anderson Neves [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil)]. E-mail: anderson@cemig.com.br

    2001-07-01

    This article presents an alternative methodology of voltage stability determination of Electrical Power System (EPS), focusing technical and economical aspects. In this direction, it presents relative aspects to mathematical modelling to analyse the phenomenon and also the influence from the most important dynamics to be taken into consideration. It is inquired the participation of generators in the rearrangement of the adopted active power in the current criteria of margin determination. A real system is analyzed, under this aspect, indicating significant variations in the calculated values for the margins, resulting in improper investments of significant values. The proposed methodology by this article seeks to contribute to minimize such mistakes, this is done by means of focusing the long duration dynamics of generators, what constitutes an important progress in relation to the researches about them.

  4. The effects of electrical stimulation on body composition and metabolic profile after spinal cord injury--Part II.

    Science.gov (United States)

    Gorgey, Ashraf S; Dolbow, David R; Dolbow, James D; Khalil, Refka K; Gater, David R

    2015-01-01

    Diet and exercise are cornerstones in the management of obesity and associated metabolic complications, including insulin resistance, type 2 diabetes, and disturbances in the lipid profile. However, the role of exercise in managing body composition adaptations and metabolic disorders after spinal cord injury (SCI) is not well established. The current review summarizes evidence about the efficacy of using neuromuscular electrical stimulation or functional electrical stimulation in exercising the paralytic lower extremities to improve body composition and metabolic profile after SCI. There are a number of trials that investigated the effects on muscle cross-sectional area, fat-free mass, and glucose/lipid metabolism. The duration of the intervention in these trials varied from 6 weeks to 24 months. Training frequency ranged from 2 to 5 days/week. Most studies documented significant increases in muscle size but no noticeable changes in adipose tissue. While increases in skeletal muscle size after twice weekly training were greater than those trials that used 3 or 5 days/week, other factors such as differences in the training mode, i.e. resistance versus cycling exercise and pattern of muscle activation may be responsible for this observation. Loading to evoke muscle hypertrophy is a key component in neuromuscular training after SCI. The overall effects on lean mass were modest and did not exceed 10% and the effects of training on trunk or pelvic muscles remain unestablished. Most studies reported improvement in glucose metabolism with the enhancement of insulin sensitivity being the major factor following training. The effect on lipid profile is unclear and warrants further investigation.

  5. The effects of electrical stimulation on body composition and metabolic profile after spinal cord injury – Part II

    Science.gov (United States)

    Gorgey, Ashraf S.; Dolbow, David R.; Dolbow, James D.; Khalil, Refka K.; Gater, David R.

    2015-01-01

    Diet and exercise are cornerstones in the management of obesity and associated metabolic complications, including insulin resistance, type 2 diabetes, and disturbances in the lipid profile. However, the role of exercise in managing body composition adaptations and metabolic disorders after spinal cord injury (SCI) is not well established. The current review summarizes evidence about the efficacy of using neuromuscular electrical stimulation or functional electrical stimulation in exercising the paralytic lower extremities to improve body composition and metabolic profile after SCI. There are a number of trials that investigated the effects on muscle cross-sectional area, fat-free mass, and glucose/lipid metabolism. The duration of the intervention in these trials varied from 6 weeks to 24 months. Training frequency ranged from 2 to 5 days/week. Most studies documented significant increases in muscle size but no noticeable changes in adipose tissue. While increases in skeletal muscle size after twice weekly training were greater than those trials that used 3 or 5 days/week, other factors such as differences in the training mode, i.e. resistance versus cycling exercise and pattern of muscle activation may be responsible for this observation. Loading to evoke muscle hypertrophy is a key component in neuromuscular training after SCI. The overall effects on lean mass were modest and did not exceed 10% and the effects of training on trunk or pelvic muscles remain unestablished. Most studies reported improvement in glucose metabolism with the enhancement of insulin sensitivity being the major factor following training. The effect on lipid profile is unclear and warrants further investigation. PMID:25001669

  6. High voltage switches having one or more floating conductor layers

    Science.gov (United States)

    Werne, Roger W.; Sampayan, Stephen; Harris, John Richardson

    2015-11-24

    This patent document discloses high voltage switches that include one or more electrically floating conductor layers that are isolated from one another in the dielectric medium between the top and bottom switch electrodes. The presence of the one or more electrically floating conductor layers between the top and bottom switch electrodes allow the dielectric medium between the top and bottom switch electrodes to exhibit a higher breakdown voltage than the breakdown voltage when the one or more electrically floating conductor layers are not present between the top and bottom switch electrodes. This increased breakdown voltage in the presence of one or more electrically floating conductor layers in a dielectric medium enables the switch to supply a higher voltage for various high voltage circuits and electric systems.

  7. Effect of low voltage electrical stimulation on biochemical and quality characteristics of Longissimus thoracis muscle from one-humped Camel (Camelus dromedaries).

    Science.gov (United States)

    Kadim, I T; Al-Hosni, Y; Mahgoub, O; Al-Marzooqi, W; Khalaf, S K; Al-Maqbaly, R S; Al-Sinawi, S S H; Al-Amri, I S

    2009-05-01

    The effects of electrical stimulation (90V) 20min post mortem on meat quality and muscle fibre types of four age group camels (1-3, 4-6, 7-9, 10-12 years) camels were assessed. Quality of the Longissimus thoracis at 1 and 7 days post mortem ageing was evaluated using shear force, pH, sarcomere length, myofibrillar fragmentation index, expressed juice, cooking loss and L(∗), a(∗), b(∗) colour values. Age of camel and electrical stimulation had a significant effect on meat quality of L. thoracis. Electrical stimulation resulted in a significantly (Pmeat was significantly (Pcamels had a significantly (Pcamels. The proportions of Type I, Type IIA and Type IIB were 25.0, 41.1 and 33.6%, respectively were found in camel meat. Muscle samples from 1-3 year camels had significantly (Pcamel samples. These results indicated that age and ES had a significant effect on camel meat quality.

  8. Unexpected guest: Atrial fibrillation due to electrical shock

    Directory of Open Access Journals (Sweden)

    Mehmet Zihni Bilik

    2016-03-01

    Full Text Available Cardiac arrhythmias due to electrical injuries are rare among emergency service admittances. A 35 year-old female patient was admitted to emergency service with palpitation after electrical injury as a result of contact with a domestic low-voltage source. Electrocardiography (ECG showed atrial fibrillation with rapid ventricular response. Transthoracic echocardiography findings were normal. Atrial fibrillation spontaneously converted to normal sinus rhythm after rate limiting treatment with beta-blocker. The patient was discharged without any complication on the third day of hospitalization. Although cardiac arrhythmias rarely occur after electrical injury, cardiac monitoring is recommended for all patients with documented rhythm disorder, loss of consciousness, or abnormal ECG at admission.

  9. Developing a Model of Care for Healing Pressure Ulcers With Electrical Stimulation Therapy for Persons With Spinal Cord Injury

    Science.gov (United States)

    Lala, D.; Houghton, P.E.; Kras-Dupuis, A.

    2016-01-01

    Background: Electrical stimulation therapy (EST) has been shown to be an effective therapy for managing pressure ulcers in individuals with spinal cord injury (SCI). However, there is a lack of uptake of this therapy, and it is often not considered as a first-line treatment, particularly in the community. Objective: To develop a pressure ulcer model of care that is adapted to the local context by understanding the perceived barriers and facilitators to implementing EST, and to describe key initial phases of the implementation process. Method: Guided by the Knowledge-to-Action (KTA) and National Implementation Research Network (NIRN) frameworks, a community-based participatory research (CBPR) approach was used to complete key initial implementation processes including (a) defining the practice, (b) identifying the barriers and facilitators to EST implementation and organizing them into implementation drivers, and (c) developing a model of care that is adapted to the local environment. Results: A model of care for healing pressure ulcers with EST was developed for the local environment while taking into account key implementation barriers including lack of interdisciplinary collaboration and communication amongst providers between and across settings, inadequate training and education, and lack of resources, such as funding, time, and staff. Conclusions: Using established implementation science frameworks with structured planning and engaging local stakeholders are important exploratory steps to achieve a successful sustainable best practice implementation project.

  10. Functional electrical stimulation-supported interval training following sensorimotor-complete spinal cord injury: a case series.

    Science.gov (United States)

    Crosbie, Jack; Russold, Michael; Raymond, Jacqui; Middleton, James W; Davis, Glen M

    2009-07-01

    Objective. To investigate the effect of interval training supported by Functional Electrical Stimulation (FES) on ambulation ability in complete spinal cord injury (SCI). Methods. We trained four men with sensorimotor-complete (ASIA A) SCI, who achieved gait through FES of the quadriceps femoris, gluteus maximus, and common peroneal nerve on each side on a motorized treadmill. Training involved progressive interval walking exercise, consisting of periods of activity followed by equal periods of rest, repeated until muscle fatigue. We used time to muscle fatigue during continuous treadmill ambulation as the primary outcome measure. We also recorded the patterns of incremental stimulation for all training and testing sessions. Results. All subjects increased their ambulation capacity; however, the responses varied from subject to subject. Some subjects increased the total distance walked by as much as 300% with progressive improvement over the entire training period; however, others made more modest gains and appeared to reach a performance plateau within a few training sessions. Conclusions. FES-supported interval training offers a useful and effective strategy for strength-endurance improvement in the large muscle groups of the lower limb in motor-complete SCI. We believe that this training protocol offers a viable alternative to that of continuous walking training in people with SCI using FES to aid ambulation. © 2009 International Neuromodulation Society.

  11. Effects of electrical stimulation pattern on quadriceps isometric force and fatigue in individuals with spinal cord injury.

    Science.gov (United States)

    Deley, Gaelle; Denuziller, Jeremy; Babault, Nicolas; Taylor, John Andrew

    2015-08-01

    Variable frequency trains (VFT) or train combinations have been suggested as useful strategies to offset the rapid fatigue induced by constant frequency trains (CFT) during electrical stimulation. However, most studies have been of short duration with limited functional application in those with spinal cord injury (SCI). We therefore tested force and fatigue in response to VFT, CFT, and combined patterns in strength training-like conditions (6-s contractions). Ten SCI individuals underwent either CFT or VFT patterns until target torque was no longer produced and then switched immediately to the other pattern. Target torque was reached more times when VFT was used first (VFT: 6.7 ± 0.8 vs. CFT: 3.5 ± 0.2 contractions, P < 0.05) and when it was followed by the CFT pattern (VFT-CFT: 10.3 ± 1.2 vs. 6.9 ± 1.2 contractions, P < 0.05). These findings suggest that for the same initial forces the VFT pattern is less fatiguing than CFT and that when combining train types, VFT should be used first. © 2014 Wiley Periodicals, Inc.

  12. Alternating stimulation of synergistic muscles during functional electrical stimulation cycling improves endurance in persons with spinal cord injury.

    Science.gov (United States)

    Decker, M J; Griffin, L; Abraham, L D; Brandt, L

    2010-12-01

    Therapeutic effects of functional electrical stimulation (FES) cycling for persons with spinal cord injury (SCI) are limited by high rates of muscular fatigue. FES-cycling performance limits and surface mechanomyography (MMG) of 12 persons with SCI were compared under two different stimulation protocols of the quadriceps muscles. One strategy used the standard "co-activation" protocol from the manufacturer of the FES cycle which involved intermittent simultaneous activation of the entire quadriceps muscle group for 400 ms. The other strategy was an "alternation" stimulation protocol which involved alternately stimulating the rectus femoris (RF) muscle for 100 ms and the vastus medialis (VM) and vastus lateralis (VL) muscles for 100 ms, with two sets with a 400 ms burst. Thus, during the alternation protocol, each of the muscle groups rested for two 100 ms "off" periods in each 400 ms burst. There was no difference in average cycling cadence (28 RPM) between the two protocols. The alternation stimulation protocol produced longer ride times and longer virtual distances traveled and used lower stimulation intensity levels with no differences in average MMG amplitudes compared to the co-activation protocol. These results demonstrate that FES-cycling performance can be enhanced by a synergistic muscle alternation stimulation strategy. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Effect of adjusting pulse durations of functional electrical stimulation cycling on energy expenditure and fatigue after spinal cord injury.

    Science.gov (United States)

    Gorgey, Ashraf S; Poarch, Hunter J; Dolbow, David D; Castillo, Teodoro; Gater, David R

    2014-01-01

    The purpose of the current study was to determine the effects of three different pulse durations (200, 350, and 500 microseconds [P200, P350, and P500, respectively]) on oxygen uptake (VO2), cycling performance, and energy expenditure (EE) percentage of fatigue of the knee extensor muscle group immediately and 48 to 72 h after cycling in persons with spinal cord injury (SCI). A convenience sample of 10 individuals with motor complete SCI participated in a repeated-measures design using a functional electrical stimulation (FES) cycle ergometer over a 3 wk period. There was no difference among the three FES protocols on relative VO2 or cycling EE. Delta EE between exercise and rest was 42% greater in both P500 and P350 compared with P200 (p = 0.07), whereas recovery VO2 was 23% greater in P350 compared with P200 (p = 0.03). There was no difference in the outcomes of the three pulse durations on muscle fatigue. Knee extensor torque significantly decreased immediately after (p < 0.001) and 48 to 72 h after (p < 0.001) FES leg cycling. Lengthening pulse duration did not affect submaximal or relative VO2 or EE, total EE, and time to fatigue. Greater recovery VO2 and delta EE were noted in P350 and P500 compared with P200. An acute bout of FES leg cycling resulted in torque reduction that did not fully recover 48 to 72 h after cycling.

  14. The effect of functional electrical stimulation cycling on late functional improvement in patients with chronic incomplete spinal cord injury.

    Science.gov (United States)

    Yaşar, E; Yılmaz, B; Göktepe, S; Kesikburun, S

    2015-12-01

    Prospective single-arm study. To investigate the effect of functional electrical stimulation (FES) cycling on late functional recovery, spasticity, gait parameters and oxygen consumption during walking in patients with chronic incomplete spinal cord injury (SCI). Turkish Armed Forces Rehabilitation Center, Ankara, Turkey. Ten patients with chronic (duration of more than 2 years) incomplete SCI who could ambulate at least 10 m independently or with the assistance of a cane or walker, but no hip-knee-ankle-foot orthosis. The subjects underwent 1-h FES cycling sessions three times a week for 16 weeks. Outcome measures including the total motor score, the Functional Independence Measure (FIM) score, the Modified Ashworth Scale for knee spasticity, temporal spatial gait parameters and oxygen consumption rate during walking were assessed at baseline, 3 and 6 months after the baseline. There were statistically significant improvements in total motor scores, the FIM scores and spasticity level at the 6-month follow-up (P0.05). Oxygen consumption rate of the patients showed significant reduction at only 6 months compared with baseline (P<0.01). The results suggest that FES cycling may provide some functional improvements in the late period of SCI. The study was supported by The Scientific and Technological Research Council of Turkey (TUBITAK).

  15. Acute Responses of Functional Electrical Stimulation Cycling on the Ventilation-to-CO2 Production Ratio and Substrate Utilization After Spinal Cord Injury.

    Science.gov (United States)

    Gorgey, Ashraf S; Lawrence, Justin

    2016-03-01

    Ventilation-to-carbon dioxide ratio is comparable with peak oxygen uptake in the prognosis of cardiovascular disorders. Currently, there are no established indices to determine the submaximal effects of functional electrical stimulation on cardiovascular performance in persons with spinal cord injury. To determine the effects of an acute bout of functional electrical stimulation-lower extremity cycling on ventilation, carbon dioxide production, ventilation-to-carbon dioxide ratio, and substrate utilization in people with motor complete spinal cord injury. Observational cross-sectional design. Clinical laboratory setting. Ten individuals with motor complete spinal cord injury. Participants were allowed to cycle until fatigue. The effects of functional electrical stimulation on ventilation, carbon dioxide production, ventilation-to-carbon dioxide ratio, and substrate utilization were measured with a portable metabolic cart (COSMED K4b2). Body composition was determined with bioelectrical impedance. Resting and warm-up ventilation were 8.15 ± 3.5 L/min and 8.15 ± 2.8 L/min, respectively. Functional electrical stimulation increased ventilation significantly (14.5 ± 6.4 L/min), which remained significantly elevated (13.3 ± 4.3 L/min) during the recovery period. During resting and warm-up phases, the ventilation-to-carbon dioxide ratios were 41 ± 4.8 and 38 ± 5.4, respectively. Functional electrical stimulation decreased the ventilation-to-carbon dioxide ratio significantly to 31.5 ± 4, which remained significantly reduced during the recovery period (34.4 ± 3). Functional electrical stimulation relied primarily on carbohydrate utilization (188 ± 160 g/day to 574 ± 324 g/day; P = .001) with no changes in fat utilization (77.5 ± 28 g/day to 93.5 ± 133.6 g/day; P = .7) from resting to exercise periods. Significant relationships were noted between carbohydrate utilization during functional electrical stimulation and carbon dioxide (r = 0.98; P = .00010

  16. Hysteresis in voltage-gated channels.

    Science.gov (United States)

    Villalba-Galea, Carlos A

    2017-03-04

    Ion channels constitute a superfamily of membrane proteins found in all living creatures. Their activity allows fast translocation of ions across the plasma membrane down the ion's transmembrane electrochemical gradient, resulting in a difference in electrical potential across the plasma membrane, known as the membrane potential. A group within this superfamily, namely voltage-gated channels, displays activity that is sensitive to the membrane potential. The activity of voltage-gated channels is controlled by the membrane potential, while the membrane potential is changed by these channels' activity. This interplay produces variations in the membrane potential that have evolved into electrical signals in many organisms. These signals are essential for numerous biological processes, including neuronal activity, insulin release, muscle contraction, fertilization and many others. In recent years, the activity of the voltage-gated channels has been observed not to follow a simple relationship with the membrane potential. Instead, it has been shown that the activity of voltage-gated channel displays hysteresis. In fact, a growing number of evidence have demonstrated that the voltage dependence of channel activity is dynamically modulated by activity itself. In spite of the great impact that this property can have on electrical signaling, hysteresis in voltage-gated channels is often overlooked. Addressing this issue, this review provides examples of voltage-gated ion channels displaying hysteretic behavior. Further, this review will discuss how Dynamic Voltage Dependence in voltage-gated channels can have a physiological role in electrical signaling. Furthermore, this review will elaborate on the current thoughts on the mechanism underlying hysteresis in voltage-gated channels.

  17. An Approach of the Continuous Electrical State Monitoring by Using the Ground Wire of Neutral Point at Extra-high Voltage Substations : A Preliminary Report

    OpenAIRE

    井筒, 潤; 原田, 誠; 寺山, 武志; 植竹, 富一; 長尾, 年恭

    2009-01-01

    We propose a new monitoring system by using the neutral current of transformers at substations of an electric power company named “neutral current monitoring”. It means that we have been measuring the telluric field by using the power line system in order to monitor the electromagnetic state of the underground over an extended time period. The principle of this system is as follow: the neutral points of the transformers in the substations are grounded to the earth and power lines connect th...

  18. Voltage Control of Magnetic Anisotropy

    Science.gov (United States)

    Hao, Guanhua; Cao, Shi; Noviasky, Nick; Ilie, Carolina; Sokolov, Andre; Yin, Yuewei; Xu, Xiaoshan; Dowben, Peter

    Pd/Co/Gd2O3/Si heterostructures were fabricated via pulsed laser deposition and e-beam evaporation. Hysteresis loops, obtained by longitudinal magneto-optical Kerr-effect (MOKE) measurements, indicates an initial in-plane magnetic anisotropy. Applying a perpendicular voltage on the sample, the differences between the polar and longitudinal MOKE and anomalous Hall effect data indicates there is a reversible change in magnetic anisotropy, from in-plane to out-of-plane, with applied voltage. Prior work by others suggests that the change in magnetic anisotropy is due to redox reactions at the Co/Gd2O3 interference. Voltage controlled magnetism can result from changing interfacial chemistry and does not always require a magneto-electric coupling tensor.

  19. Standing with electrical stimulation and splinting is no better than standing alone for management of ankle plantarflexion contractures in people with traumatic brain injury: a randomised trial.

    Science.gov (United States)

    Leung, Joan; Harvey, Lisa A; Moseley, Anne M; Whiteside, Bhavini; Simpson, Melissa; Stroud, Katarina

    2014-12-01

    Is a combination of standing, electrical stimulation and splinting more effective than standing alone for the management of ankle contractures after severe brain injury? A multi-centre randomised trial with concealed allocation, assessor blinding and intention-to-treat analysis. Thirty-six adults with severe traumatic brain injury and ankle plantarflexion contractures. All participants underwent a 6-week program. The experimental group received tilt table standing, electrical stimulation and ankle splinting. The control group received tilt table standing alone. The primary outcome was passive ankle dorsiflexion with a 12Nm torque. Secondary outcomes included: passive dorsiflexion with lower torques (3, 5, 7 and 9Nm); spasticity; the walking item of the Functional Independence Measure; walking speed; global perceived effect of treatment; and perceived treatment credibility. OUTCOME MEASURES were taken at baseline (Week 0), end of intervention (Week 6), and follow-up (Week 10). The mean between-group differences (95% CI) for passive ankle dorsiflexion at Week 6 and Week 10 were -3 degrees (-8 to 2) and -1 degrees (-6 to 4), respectively, in favour of the control group. There was a small mean reduction of 1 point in spasticity at Week 6 (95% CI 0.1 to 1.8) in favour of the experimental group, but this effect disappeared at Week 10. There were no differences for other secondary outcome measures except the physiotherapists' perceived treatment credibility. Tilt table standing with electrical stimulation and splinting is not better than tilt table standing alone for the management of ankle contractures after severe brain injury. ACTRN12608000637347. [Leung J, Harvey LA, Moseley AM, Whiteside B, Simpson M, Stroud K (2014) Standing with electrical stimulation and splinting is no better than standing alone for management of ankle plantarflexion contractures in people with traumatic brain injury: a randomised trial.Journal of Physiotherapy60: 201-208]. Copyright © 2014

  20. Standing with electrical stimulation and splinting is no better than standing alone for management of ankle plantarflexion contractures in people with traumatic brain injury: a randomised trial

    Directory of Open Access Journals (Sweden)

    Joan Leung

    2014-12-01

    Full Text Available Question: Is a combination of standing, electrical stimulation and splinting more effective than standing alone for the management of ankle contractures after severe brain injury? Design: A multi-centre randomised trial with concealed allocation, assessor blinding and intention-to-treat analysis. Participants: Thirty-six adults with severe traumatic brain injury and ankle plantarflexion contractures. Intervention: All participants underwent a 6-week program. The experimental group received tilt table standing, electrical stimulation and ankle splinting. The control group received tilt table standing alone. Outcome measures: The primary outcome was passive ankle dorsiflexion with a 12 Nm torque. Secondary outcomes included: passive dorsiflexion with lower torques (3, 5, 7 and 9 Nm; spasticity; the walking item of the Functional Independence Measure; walking speed; global perceived effect of treatment; and perceived treatment credibility. Outcome measures were taken at baseline (Week 0, end of intervention (Week 6, and follow-up (Week 10. Results: The mean between-group differences (95% CI for passive ankle dorsiflexion at Week 6 and Week 10 were –3 degrees (–8 to 2 and –1 degrees (–6 to 4, respectively, in favour of the control group. There was a small mean reduction of 1 point in spasticity at Week 6 (95% CI 0.1 to 1.8 in favour of the experimental group, but this effect disappeared at Week 10. There were no differences for other secondary outcome measures except the physiotherapists’ perceived treatment credibility. Conclusion: Tilt table standing with electrical stimulation and splinting is not better than tilt table standing alone for the management of ankle contractures after severe brain injury. Trial registration: ACTRN12608000637347. [Leung J, Harvey LA, Moseley AM, Whiteside B, Simpson M, Stroud K (2014 Standing with electrical stimulation and splinting is no better than standing alone for management of ankle plantarflexion

  1. Design and control of single-phase dynamic voltage restorer

    Indian Academy of Sciences (India)

    Dynamic voltage restorer (DVR) is a custom power device used in electrical distribution system for power quality improvement. It ensures regulated voltage supply to the sensitive loads, even in case of voltage sag and swell disturbances in the distribution network. It is a series connected device and compensates voltagesag ...

  2. 46 CFR 183.324 - Dual voltage generators.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Dual voltage generators. 183.324 Section 183.324... TONS) ELECTRICAL INSTALLATION Power Sources and Distribution Systems § 183.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel shall be of the grounded type, where: (1) The...

  3. 46 CFR 111.01-17 - Voltage and frequency variations.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Voltage and frequency variations. 111.01-17 Section 111... ELECTRIC SYSTEMS-GENERAL REQUIREMENTS General § 111.01-17 Voltage and frequency variations. Unless... and +6 percent to −10 percent of rated voltage. This limitation does not address transient conditions. ...

  4. Long-term exposure to electric fields. A cross-sectional epidemiologic investigation of occupationally exposed workers in high-voltage substations.

    Science.gov (United States)

    Knave, B; Gamberale, F; Bergström, S; Birke, E; Iregren, A; Kolmodin-Hedman, B; Wennberg, A

    1979-06-01

    In the present epidemiologic study, 53 workers with a long-term (more than five years) exposure to the electric field of 400 kV substations were examined and compared with a matched reference group of 53 nonexposed workers from the same power companies. Matching variables included age, geographic location and employment time. The aim of the study was to investigate the possibility of persistent, chronic health effects in the exposed group as a consequence of exposure. The investigation indluded the nervous system (neurasthenic symptoms, psychological tests, electroencephalography), the cardiovascular system (symptoms, blood pressure, electrocardiography), and the blood (hemoglobin, red blood cells, reticulocytes, white blood cells including differential count, thrombocytes, sedimentation rate). Fertility was also assessed. The results showed no differences between the exposed and reference groups as a consequence of the long-term exposure to the electric fields. The groups differed, however, in that the exposed group had (a) consistently better results on the psychological performance tests, (b) a fewer number of children, especially boys, and (c) somewhat higher education. The differences in test results were due to the higher education among the exposed. The difference in number of children was also thought to be related to factors other than exposure since it was found to be present already 10--15 years before the work in 400 kV substations began.

  5. Effectiveness of bisphosphonate analogues and functional electrical stimulation on attenuating post-injury osteoporosis in spinal cord injury patients- a systematic review and meta-analysis.

    Science.gov (United States)

    Chang, Ke-Vin; Hung, Chen-Yu; Chen, Wen-Shiang; Lai, Mei-Shu; Chien, Kuo-Liong; Han, Der-Sheng

    2013-01-01

    Various pharmacologic and non-pharmacologic approaches have been applied to reduce sublesional bone loss after spinal cord injury (SCI), and the results are inconsistent across the studies. The objective of this meta-analysis was to investigate whether the two most-studied interventions, bisphosphonate analogues and functional electrical stimulation (FES), could effectively decrease bone mineral density (BMD) attenuation and/or restore lost BMD in the SCI population. Randomized controlled trials, quasi-experimental studies, and prospective follow-up studies employing bisphosphonates or FES to treat post-SCI osteoporosis were identified in PubMed and Scopus. The primary outcome was the percentage of BMD change from baseline measured by dual-energy X-ray absorptiometry (DEXA) or computed tomography (CT). Data were extracted from four points: the 3rd, 6th, 12th, and 18th month after intervention. A total of 19 studies were included in the analysis and involved 364 patients and 14 healthy individuals. Acute SCI participants treated with bisphosphonate therapy demonstrated a trend toward less bone loss than participants who received placebos or usual care. A significant difference in BMD decline was noted between both groups at the 3rd and 12th month post-medication. The subgroup analysis failed to show the superiority of intravenous bisphosphonate over oral administration. Regarding FES training, chronic SCI patients had 5.96% (95% CI, 2.08% to 9.84%), 7.21% (95%CI, 1.79% to 12.62%), and 9.56% (95% CI, 2.86% to 16.26%) increases in BMD at the 3rd, 6th, and 12th months post-treatment, respectively. The studies employing FES ≥ 5 days per week were likely to have better effectiveness than studies using FES ≤ 3 days per week. Our meta-analysis indicated bisphosphonate administration early following SCI effectively attenuated sublesional bone loss. FES intervention for chronic SCI patients could significantly increase sublesional BMD near the site of maximal mechanical

  6. [Effects of low molecular weight heparin on the inflammatory response and vascular injury in rat after electric burn].

    Science.gov (United States)

    Jiang, Nanhong; Xie, Weiguo; Wang, Hui; Jin, Dongmei; Tan, Hong; Zhao, Chaoli

    2014-04-01

    To observe the effects of low molecular weight heparin (LMWH) on the inflammatory response and vascular injury in rat after electric burn. A homemade regulator and transformer apparatus was used to reproduce the model of electric burn (0.5 cm×0.5 cm in size) with depth from full-thickness to full-thickness skin plus muscle and bone on the middle of the inside of right hind limb in 60 Wistar rats. The open wounds were covered with 20 g/L sulfadiazine silver paste immediately after injury. The wound condition was observed every day. The injured rats were divided into group LMWH and control group (C) according to the random number table, with 30 rats in each group. Rats in group LMWH were given subcutaneous injection of LMWH (1 U/g) in abdominal wall, 2 times a day. No other treatment was given in rats in group C. On post burn day (PBD) 3, 5, and 10, 10 rats respectively of two groups were sacrificed. The damaged tissue of wound and that around the wound (1.0 cm×0.5 cm in size) were excised, and heart blood was obtained. The pathological changes and thrombosis in damaged tissue were observed with HE, Masson, and aldehyde fuchsin staining, and the thrombosis rate was calculated. Serum contents of TNF-α and endothelin-1 were determined with ELISA. The mRNA expression of TNF-α in damaged tissue was detected with RT-PCR. Data were processed with Levene homogeneity test, analysis of variance of factorial design, LSD- t test, SNK- q test, and Friedman M nonparametric test. (1) The injured limb of rats was obviously swollen after electric burn, which reached deeply to the muscle and bone. Compared with those of group C, the swelling of rats subsided slightly faster and the inflammatory response was lighter in group LMWH at each time point. (2) The necrosis of damaged tissue and profuse infiltration of inflammatory cells were observed. Dilatation of blood vessels, congestion and thrombosis, and swelling, necrosis, and desquamation of vascular endothelial cells were

  7. Voltage control of ferromagnetic resonance

    Directory of Open Access Journals (Sweden)

    Ziyao Zhou

    2016-06-01

    Full Text Available Voltage control of magnetism in multiferroics, where the ferromagnetism and ferroelectricity are simultaneously exhibiting, is of great importance to achieve compact, fast and energy efficient voltage controllable magnetic/microwave devices. Particularly, these devices are widely used in radar, aircraft, cell phones and satellites, where volume, response time and energy consumption is critical. Researchers realized electric field tuning of magnetic properties like magnetization, magnetic anisotropy and permeability in varied multiferroic heterostructures such as bulk, thin films and nanostructure by different magnetoelectric (ME coupling mechanism: strain/stress, interfacial charge, spin–electromagnetic (EM coupling and exchange coupling, etc. In this review, we focus on voltage control of ferromagnetic resonance (FMR in multiferroics. ME coupling-induced FMR change is critical in microwave devices, where the electric field tuning of magnetic effective anisotropic field determines the tunability of the performance of microwave devices. Experimentally, FMR measurement technique is also an important method to determine the small effective magnetic field change in small amount of magnetic material precisely due to its high sensitivity and to reveal the deep science of multiferroics, especially, voltage control of magnetism in novel mechanisms like interfacial charge, spin–EM coupling and exchange coupling.

  8. Low-Voltage Consumption Coordination for Loss Minimization and Voltage Control

    DEFF Research Database (Denmark)

    Juelsgaard, Morten; Sloth, Christoffer; Wisniewski, Rafal

    2014-01-01

    This work presents a strategy for minimizing active power losses in low-voltage grids, by coordinating the consumption of electric vehicles and power generation from solar panels. We show that minimizing losses, also reduces voltage variations, and illustrate how this may be employed for increasing...

  9. Voltage resonance phenomenon and simulation of electrical properties of (FeCoZr)x(PbZrTiO3)(100-x) nanocomposite films

    Science.gov (United States)

    Boiko, Oleksandr

    2017-08-01

    In this paper, the frequency dependencies of phase angle, capacity in a parallel replacement system, conductivity and loss coefficient of ferromagnetic alloy - ferroelectric ceramics nanocomposite (FeCoZr)x(PbZrTiO3)(100-x) with x = 55.9 at.% were studied. Tested material was deposited by ion beam sputtering with use of mixed argon-oxygen atmosphere in a vacuum chamber and subdued by a 15-min annealing in air in the temperature of Ta =498 K. The type of electrical conduction in the material for frequencies f parallel connection of two branches with serial RLC elements were performed for the frequency range 50 Hz RLC circuits of electronic components and finding other applications of (FeCoZr)x(PbZrTiO3)(100-x) nanocomposites in electronics and engineering.

  10. Voltage stability in low voltage microgrids in aspects of active and reactive power demand

    Directory of Open Access Journals (Sweden)

    Parol Mirosław

    2016-03-01

    Full Text Available Low voltage microgrids are autonomous subsystems, in which generation, storage and power and electrical energy consumption appear. In the paper the main attention has been paid to the voltage stability issue in low voltage microgrid for different variants of its operation. In the introduction a notion of microgrid has been presented, and also the issue of influence of active and reactive power balance on node voltage level has been described. Then description of voltage stability issue has been presented. The conditions of voltage stability and indicators used to determine voltage stability margin in the microgrid have been described. Description of the low voltage test microgrid, as well as research methodology along with definition of considered variants of its operation have been presented further. The results of exemplary calculations carried out for the daily changes in node load of the active and reactive power, i.e. the voltage and the voltage stability margin indexes in nodes have been presented. Furthermore, the changes of voltage stability margin indexes depending on the variant of the microgrid operation have been presented. Summary and formulation of conclusions related to the issue of voltage stability in microgrids have been included at the end of the paper.

  11. Power amplifier circuits for functional electrical stimulation systems

    OpenAIRE

    Souza, Delmar Carvalho de; Gaiotto, Marcelo do Carmo; Nogueira Neto,Guilherme Nunes; Castro,Maria Claudia Ferrari de; Nohama, Percy

    2017-01-01

    Abstract Introduction: Functional electrical stimulation (FES) is a technique that has been successfully employed in rehabilitation treatment to mitigate problems after spinal cord injury (SCI). One of the most relevant modules in a typical FES system is the power or output amplifier stage, which is responsible for the application of voltage or current pulses of proper intensity to the biological tissue, applied noninvasively via electrodes, placed on the skin surface or inside the muscular ...

  12. Experimental investigation of SDBD plasma actuator driven by AC high voltage with a superimposed positive pulse bias voltage

    Science.gov (United States)

    Qi, Xiao-Hua; Yan, Hui-Jie; Yang, Liang; Hua, Yue; Ren, Chun-Sheng

    2017-08-01

    In this work, a driven voltage consisting of AC high voltage with a superimposed positive pulse bias voltage ("AC+ Positive pulse bias" voltage) is adopted to study the performance of a surface dielectric barrier discharge plasma actuator under atmospheric conditions. To compare the performance of the actuator driven by single-AC voltage and "AC+ Positive pulse bias" voltage, the actuator-induced thrust force and power consumption are measured as a function of the applied AC voltage, and the measured results indicate that the thrust force can be promoted significantly after superimposing the positive pulse bias voltage. The physical mechanism behind the thrust force changes is analyzed by measuring the optical properties, electrical characteristics, and surface potential distribution. Experimental results indicate that the glow-like discharge in the AC voltage half-cycle, next to the cycle where a bias voltage pulse has been applied, is enhanced after applying the positive pulse bias voltage, and this perhaps is the main reason for the thrust force increase. Moreover, surface potential measurement results reveal that the spatial electric field formed by the surface charge accumulation after positive pulse discharge can significantly affect the applied external electric field, and this perhaps can be responsible for the experimental phenomenon that the decrease of thrust force is delayed by pulse bias voltage action after the filament discharge occurs in the glow-like discharge region. The schlieren images further verify that the actuator-induced airflow velocity increases with the positive pulse voltage.

  13. A Quantification of the Energy Savings by Conservation Voltage Reduction

    NARCIS (Netherlands)

    Ellens, W.; Berry, A.; West, S.

    2013-01-01

    The introduction of `Smart grid' technologies in the electricity supply industry has attracted new attention to Conservation Voltage Reduction (CVR). CVR is a method that aims to save energy by reducing the voltage level of the electrical distribution network. However, not all devices consume less

  14. Fuel Cell/Electrochemical Cell Voltage Monitor

    Science.gov (United States)

    Vasquez, Arturo

    2012-01-01

    A concept has been developed for a new fuel cell individual-cell-voltage monitor that can be directly connected to a multi-cell fuel cell stack for direct substack power provisioning. It can also provide voltage isolation for applications in high-voltage fuel cell stacks. The technology consists of basic modules, each with an 8- to 16-cell input electrical measurement connection port. For each basic module, a power input connection would be provided for direct connection to a sub-stack of fuel cells in series within the larger stack. This power connection would allow for module power to be available in the range of 9-15 volts DC. The relatively low voltage differences that the module would encounter from the input electrical measurement connection port, coupled with the fact that the module's operating power is supplied by the same substack voltage input (and so will be at similar voltage), provides for elimination of high-commonmode voltage issues within each module. Within each module, there would be options for analog-to-digital conversion and data transfer schemes. Each module would also include a data-output/communication port. Each of these ports would be required to be either non-electrical (e.g., optically isolated) or electrically isolated. This is necessary to account for the fact that the plurality of modules attached to the stack will normally be at a range of voltages approaching the full range of the fuel cell stack operating voltages. A communications/ data bus could interface with the several basic modules. Options have been identified for command inputs from the spacecraft vehicle controller, and for output-status/data feeds to the vehicle.

  15. Changes in electrical perception threshold within the first 6 months after traumatic spinal cord injury: a multicenter responsiveness study.

    Science.gov (United States)

    van Hedel, Hubertus J A; Kumru, Hatice; Röhrich, Frank; Galen, Sujay

    2012-06-01

    To assess the reliability of the electrical perception threshold (EPT) in healthy participants and its responsiveness in patients for 6 months after traumatic spinal cord injury (SCI). The reliability of EPT measures was assessed in 15 healthy volunteers (from C3 to S2). EPT measures were assessed in 37 patients at 1, 3, and 6 months after SCI. EPT was determined in dermatomes at, above, and below the neurological level of lesion. Reliability was quantified with an intraclass correlation coefficient (ICC) and responsiveness with the standardized response mean (SRM). Dermatomes were classified as having normal or pathological sensory perception, based on both light touch (LT) and EPT testing. The percentage of agreement between LT and EPT classifications was determined. The ICCs varied considerably between dermatomes (0.00 ≤ ICC ≤ 0.86). Overall, EPTs changed little within the first 6 months after SCI, resulting in small SRM values. Agreement between classifications according to EPT or LT testing varied from 30% to 100%. The least agreement was observed in the first segment below the lesion. Future studies must note that the reliability of EPT differs between dermatomes in healthy participants. Furthermore, at and below the level of the lesion, spontaneous recovery of sensory perception is poor within the first 6 months after SCI. Based on subgroup analyses, if a translational trial aims to improve sensory perception around the level of the lesion, sensory-incomplete tetraplegic patients could be included. These patients show poor spontaneous recovery, and the EPT may detect subtle changes in perception.

  16. Electrical stimulation plus progressive resistance training for leg strength in spinal cord injury: a randomized controlled trial.

    Science.gov (United States)

    Harvey, L A; Fornusek, C; Bowden, J L; Pontifex, N; Glinsky, J; Middleton, J W; Gandevia, S C; Davis, G M

    2010-07-01

    A randomized controlled trial. To determine the effectiveness of electrical stimulation (ES)-evoked muscle contractions superimposed on progressive resistance training (PRT) for increasing voluntary strength in the quadriceps muscles of people with spinal cord injuries (SCI). Sydney, Australia. A total of 20 people with established SCI and neurologically induced weakness of the quadriceps muscles participated in the trial. Participants were randomized between experimental and control groups. Volunteers in the experimental group received ES superimposed on PRT to the quadriceps muscles of one leg thrice weekly for 8 weeks. Participants in the control group received no intervention. Assessments occurred at the beginning and at the end of the 8-week period. The four primary outcomes were voluntary strength (Nm) and endurance (fatigue ratio) as well as the performance and satisfaction items of the Canadian Occupational Performance Measure (COPM; points). The between-group mean differences (95% confidence interval (CI)) for voluntary strength and endurance were 14 Nm (1-27; P=0.034) and 0.1 (-0.1 to 0.3; P=0.221), respectively. The between-group median differences (95% CI) for the performance and satisfaction items of the COPM were 1.7 points (-0.2 to 3.2; P=0.103) and 1.4 points (-0.1 to 4.6; P=0.058), respectively. ES superimposed on PRT improves voluntary strength, although there is uncertainty about whether the size of the treatment effect is clinically important. The relative effectiveness of ES and PRT is yet to be determined.

  17. Stimulation of shank muscles during functional electrical stimulation cycling increases ankle excursion in individuals with spinal cord injury.

    Science.gov (United States)

    Fornusek, Ché; Davis, Glen M; Baek, Ilhun

    2012-11-01

    To investigate the effect of shank muscle stimulation on ankle joint excursion during passive and functional electrical stimulation (FES) leg cycling. Within-subject comparisons. Laboratory setting. Well-trained FES cyclists (N=7) with chronic spinal cord injuries. Two experimental sessions were performed on an isokinetic FES cycle ergometer with a pedal boot that allowed the ankle to plantarflex and dorsiflex during cycling. During the first session, the optimal stimulation timings to induce plantarflexion and dorsiflexion were investigated by systematically altering the stimulation angles of the shank muscles (tibialis anterior [TA] and triceps surae [TS]). During the second session, TA and TS stimulation was included with standard FES cycling (quadriceps, hamstrings, and gluteals) for 6 subjects. Ankle, knee, and hip movements were analyzed using 2-dimensional video. The ankle excursions during passive cycling were 19°±6°. TA and TS stimulation increased ankle joint excursion up to 33°±10° and 27°±7°, respectively. Compared with passive cycling, ankle joint excursion was not significantly increased during standard FES cycling (24°±7°). TA and TS stimulation significantly increased the ankle excursion when applied during standard FES cycling (41°±4°). Freeing the ankle joint to rotate during FES cycling was found to be safe. The combination of shank muscle stimulation and repetitive ankle joint movement may be beneficial for improving ankle flexibility and leg conditioning. Further research is required to test and design ankle supports that might maximize the benefits of shank muscle activation. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  18. Distribution System Voltage Regulation by Distributed Energy Resources

    Energy Technology Data Exchange (ETDEWEB)

    Ceylan, Oguzhan [ORNL; Liu, Guodong [ORNL; Xu, Yan [ORNL; Tomsovic, Kevin [University of Tennessee, Knoxville (UTK)

    2014-01-01

    This paper proposes a control method to regulate voltages in 3 phase unbalanced electrical distribution systems. A constrained optimization problem to minimize voltage deviations and maximize distributed energy resource (DER) active power output is solved by harmony search algorithm. IEEE 13 Bus Distribution Test System was modified to test three different cases: a) only voltage regulator controlled system b) only DER controlled system and c) both voltage regulator and DER controlled system. The simulation results show that systems with both voltage regulators and DER control provide better voltage profile.

  19. Loss minimization and voltage control in smart distribution grid

    DEFF Research Database (Denmark)

    Juelsgaard, Morten; Sloth, Christoffer; Wisniewski, Rafael

    2014-01-01

    This work presents a strategy for increasing the installation of electric vehicles and solar panels in low-voltage grids, while obeying voltage variation constraints. Our approach employs minimization of active power losses for coordinating consumption and generation of power, as well as reactive...... power control to maintain satisfactory grid operation. Numerical case studies illustrate how our approach can significantly increase installation of both electric vehicles and solar panels, while avoiding unsatisfactory over- and under-voltages throughout the grid....

  20. Loss Minimization and Voltage Control in Smart Distribution Grid

    DEFF Research Database (Denmark)

    Juelsgaard, Morten; Sloth, Christoffer; Wisniewski, Rafal

    2014-01-01

    This work presents a strategy for increasing the installation of electric vehicles and solar panels in low-voltage grids, while obeying voltage variation constraints. Our approach employs minimization of active power losses for coordinating consumption and generation of power, as well as reactive...... power control to maintain satisfactory grid operation. Numerical case studies illustrate how our approach can significantly increase installation of both electric vehicles and solar panels, while avoiding unsatisfactory over- and under-voltages throughout the grid....

  1. Control voltage of the generator of auto-excited induction for applications on micro/mini generation o electric power; Control de voltaje del generador de induccion auto-excitado para aplicaciones de micro/mini generacion de energia electrica

    Energy Technology Data Exchange (ETDEWEB)

    Torres Montalvo, Emmanuel

    2006-09-15

    Although only one part of the mini/micro hydraulic power has been exploited in our country, this type of electric energy generation can be considered as a visible way of electricity generation, mainly related to the ecological, economical and social aspects. The impact that these power plants can have in the regions in which they are installed is always positive: cost energy cost reduction, economical spills and mainly a social welfare. The electric energy is one of the pillars for the economical development of a country and provides a better life quality. Nowadays the research and the technology oriented to the operation and control of the micro/mini power plants has awaken the interest of many researchers in several countries of the world as China, India, Canada, and USA to mention some of them. The induction generator plays a crucial role in the uses of these technologies. The work of Basset and Potter in 1935 is the angular stone over the possibility of generating energy making use of the induction machine and a capacitors bank connected to the machine terminals. This configuration is known as induction auto-excited generator (GIAE). Several investigations have been realized that deal about the functioning principle and the dynamic behavior a GIAE, which can supply electric power in remote isolated regions. In the existing literature have been proposed control strategies to offer voltage regulations and/or frequency into the acceptable range. Some of these control strategies present problems such a demand of a reactive power, harmonics injections in the system, the control circuits are complicated, expensive and voluminous and prone to fail. This paper realizes an analysis of the necessary and sufficient conditions so that an induction machine can operate as GIAE. The corresponding curves are presented for each studied case. The dynamic behavior of the voltage and the frequency generated by the GIAE are studied in detail, which is a contribution to the existing

  2. DVR(Dynamic Voltage Restorer)

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. DVR(Dynamic Voltage Restorer). Supply voltage Sag compensation. Supply voltage Swell Compensation. Balancing the Load voltage. Compensation of Supply Voltage Harmonics.

  3. Bilateral Electrical Cataract: A Case Report

    Directory of Open Access Journals (Sweden)

    Selçuk Sızmaz

    2011-06-01

    Full Text Available To present a rare complication, such as bilateral cataracts, in a man who sustained a high-voltage electrical injury. A 35- year-old man was admitted with a complaint of decrease in visual acuity. He had a history of a contact with a power line carrying 30.000 volts of electricity while working at a construction site. Examination at a burn center revealed second-degree facial, neck and left foot burns. One month later, the patient underwent amputation of fourth and fifth toes of his left foot. During the next 6 months, he noted decreasing vision in both eyes. Ocular examination 1 year after the accident revealed that the patient’s visual acuity had deteriorated to 1/10 in both eyes. The cornea on the left eye showed superficial punctate opacities. The lenses in both eyes had anterior subcapsular cortical lens opacities and posterior subcapsular opacities. Uncomplicated bilateral phacoemulsification surgery with intraocular lens implantation was performed and the patient’s visual acuity returned to 10/10 in both eyes. We noted that the fundus remained normal in both eyes. Electrical cataracts are still a serious potential complication that may occur after electrical injury. Awareness of this by burn team members is important for providing optimal treatment to those who have suffered an electrical injury. (Turk J Ophthalmol 2011; 41: 197-9

  4. Whole-body magnetic resonance in localization of a compartment syndrome in a high-voltage injury – a case-report [Ganzkörper-MRT zur Lokalisation eines Kompartmentsyndroms beim Starkstromverletzten – ein Fallbericht

    Directory of Open Access Journals (Sweden)

    Reichert, Bert

    2011-12-01

    Full Text Available [english] An 18-year-old male is suffering from a high-voltage injury and within only few hours develops very high serum levels of creatine kinase as well as brown colored urine. This indicates a compartment syndrome, but it is not possible to find its exact location only by clinical means. Therefore we immediately performed a MRI of the whole body. The area damaged most intensely was found in the right thigh and therefore we performed limited fasciotomy there. The tissue recovered within a few minutes. 6 months later no functional impairments have remained.[german] Ein 18-jähriger Mann wird durch Einwirkung von Hochspannung schwer verletzt und entwickelt innerhalb weniger Stunden einen drastischen Anstieg der Creatrininkinase (CK sowie eine deutliche Verfärbung des Urins. Klinisch lässt sich das deswegen als sicher zu vermutende, aufgrund ödematöser Schwellung entstandene Kompartmentsyndrom allerdings nicht eindeutig lokalisieren, so dass eine notfallmäßige Ganzkörper-MRT erfolgt. Diese stellt als Zone der maximalen Muskelschädigung einen Abschnitt des rechten Oberschenkels hochsensitiv dar, so dass daraufhin eine Dekompression erfolgt, die auf diese Lokalisation beschränkt bleiben darf. Innerhalb weniger Minuten erholt sich das Muskelgewebe. Nach sechs Monaten sind keine funktionellen Residuen verblieben.

  5. Electrical stimulation and splinting were not clearly more effective than splinting alone for contracture management after acquired brain injury: a randomised trial.

    Science.gov (United States)

    Leung, Joan; Harvey, Lisa A; Moseley, Anne M; Tse, Charis; Bryant, Jane; Wyndham, Shirley; Barry, Siobhan

    2012-01-01

    Is electrical stimulation and splinting more effective than splinting alone for the management of wrist contracture following acquired brain injury? A multi-centre randomised trial with concealed allocation, assessor blinding, and intention-to-treat analysis. Thirty-six adults with first stroke or traumatic brain injury and mild to moderate wrist flexion contractures. The experimental group received electrical stimulation to the wrist and finger extensor muscles for 1 hour a day over 4 weeks while the control group did not. Both groups wore a splint for 12 hours a day during this 4-week period. The primary outcome was passive wrist extension measured with a 3Nm torque and with the fingers in extension. Secondary outcomes included passive wrist extension, wrist and finger extensor strength, wrist flexor spasticity, motor control of the hand, and Global Perceived Effect of Treatment, and perception of treatment credibility. Outcome measures were taken at baseline, at the end of the intervention period (4 weeks), and after a 2-week follow-up period (6 weeks). At 4 and 6 weeks, the mean between-group difference (95% CI) for passive wrist extension was 7 degrees (-2 to 15) and -3 degrees (-13 to 7), respectively. Secondary outcomes were statistically non-significant or were of borderline statistical significance. It is not clear whether electrical stimulation and splinting is more effective than splinting alone for the management of wrist contracture after acquired brain injury. Therapists' confidence in the efficacy of electrical stimulation for contracture management is not yet justified. Copyright © 2012 Australian Physiotherapy Association. Published by .. All rights reserved.

  6. Electrode voltage fall and total voltage of a transient arc

    Science.gov (United States)

    Valensi, F.; Ratovoson, L.; Razafinimanana, M.; Masquère, M.; Freton, P.; Gleizes, A.

    2016-06-01

    This paper deals with an experimental study of the components of a transient arc total voltage with duration of a few tens of ms and a current peak close to 1000 A. The cathode tip is made of graphite whereas the flat anode is made either of copper or of graphite; the electrodes gap is a few mm. The analysis of the electrical parameters is supported and validated by fast imaging and by two models: the first one is a 2D physical model of the arc allowing to calculate both the plasma temperature field and the arc voltage; the second model is able to estimate the transient heating of the graphite electrode. The main aim of the study was to detect the possible change of the cathode voltage fall (CVF) during the first instants of the arc. Indeed it is expected that during the first ms the graphite cathode is rather cool and the main mechanism of the electron emission should be the field effect emission, whereas after several tens of ms the cathode is strongly heated and thermionic emission should be predominant. We have observed some change in the apparent CVF but we have shown that this apparent change can be attributed to the variation of the solid cathode resistance. On the other hand, the possible change of CVF corresponding to the transition between a ‘cold’ and a ‘hot’ cathode should be weak and could not be characterized considering our measurement uncertainty of about 2 V. The arc column voltage (ACV) was estimated by subtracting the electrode voltage fall from the total arc voltage. The experimental transient evolution of the ACV is in very good agreement with the theoretical variation predicted by the model, showing the good ability of the model to study this kind of transient arc.

  7. Correlation of renal complications with extent and progression of tissue damage in electrical burns

    Directory of Open Access Journals (Sweden)

    Chauhan D

    2004-01-01

    Full Text Available Electrical injuries due to high-tension voltage (>1000 volts cause destruction at the point of contact with massive necrosis of deeper structures such as muscles, vessels and nerves. Rhabdomyolysis due to massive breakdown of skeletal muscles may lead to acute renal failure secondary to myoglobinuria. The study was undertaken to observe the correlation of renal complications with extent and progression of tissue damage in high-tension voltage electrical burns. Renal biochemical parameters as predictors of acute renal failure were also studied. Thirty two patients of high tension voltage electrical burn injuries presenting during one year period 1-1-2001 to 31-12-2001 were studied. Low-tension voltage electrical injuries (< 1000 volts mimic thermal burns were excluded from the study. The electrical wound assessment and the renal biochemical parameters were done daily for the first seven days and then on alternate days for another seven days. Assessment of progression of wounds and correlation with the renal biochemical parameters was done. Patients who died following electrical burns were subjected to autopsy and histopathological examination of both kidneys. Out of the thirty-two patients, six (18.75% went into acute renal failure. Five out of these six patients died because of renal failure (mortality rate 83.33%. There was definite progression of electric burn wounds. There was no correlation between progression of electrical burn wounds and acute renal failure. Serum creatinine was found to be the most important biochemical parameter as a prognostic indicator of acute renal failure.

  8. Pilot study of the effect of low-cadence functional electrical stimulation cycling after spinal cord injury on thigh girth and strength.

    Science.gov (United States)

    Fornusek, Ché; Davis, Glen Macartney; Russold, Michael Friedrich

    2013-05-01

    To investigate the long-term effects of functional electrical stimulation (FES)-evoked cycle training cadence on leg muscle hypertrophy and electrically evoked strength. Open intervention study. Laboratory setting. Untrained individuals with chronic spinal cord injury (N=8). Six weeks (3d/wk) of training on an isokinetic FES cycle ergometer. For each subject, 1 leg was randomly allocated to cycling at 10 revolutions per minute (rpm) (LOW) for 30min/d, and the other cycling at 50rpm (HIGH) for 30min/d. Pre- and posttraining measurements of lower limb circumference were performed at the distal and middle position of each thigh. Electrically evoked quadriceps muscle torque during an isometric contraction was also assessed. Six weeks of FES cycle training significantly increased thigh girth in both LOW and HIGH groups. At midthigh, girth increases induced by LOW (6.6%±1.2%) were significantly greater than those by HIGH (3.6%±0.8%). LOW also produced greater gains in electrically evoked isometric torque than HIGH after training. These results suggest that lower pedaling cadences evoke greater muscle hypertrophy and electrically stimulated muscle strength compared with higher cadences. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  9. Optimization of Bi2O3, TiO2, and Sb2O3 doped ZnO-based low-voltage varistor ceramic to maximize nonlinear electrical properties.

    Science.gov (United States)

    Dorraj, Masoumeh; Zakaria, Azmi; Abdollahi, Yadollah; Hashim, Mansor; Moosavi, Seyedehmaryam

    2014-01-01

    In ZnO-based low voltage varistor, the two essential features of microstructure determining its nonlinear response are the formation Bi-enriched active grain boundaries as well as a controlled ZnO grain size by secondary spinel-type phases. Besides, the microstructure and phase composition are strongly affected by the dopant concentration during sintering process. In this study, the optimal dopant levels of Bi2O3, TiO2, and Sb2O3 to achieve maximized nonlinear electrical property (alpha) were quantified by the response surface methodology (RSM). RSM was also used to understand the significance and interaction of the factors affecting the response. Variables were determined as the molar ratio of Bi2O3, TiO2, and Sb2O3. The alpha was chosen as response in the study. The 5-level-3-factor central composite design, with 20 runs, was used to conduct the experiments by ball milling method. A quadratic model was established as a functional relationship between three independent variables and alpha. According to the results, the optimum values of Bi2O3, TiO2, and Sb2O3 were obtained 0.52, 0.50, and 0.30, respectively. Under optimal conditions the predicted alpha (9.47) was calculated using optimal coded values from the model and the theoretical value is in good agreement with the value (9.43) obtained by confirmation experiment.

  10. Optimization of Bi2O3, TiO2, and Sb2O3 Doped ZnO-Based Low-Voltage Varistor Ceramic to Maximize Nonlinear Electrical Properties

    Directory of Open Access Journals (Sweden)

    Masoumeh Dorraj

    2014-01-01

    Full Text Available In ZnO-based low voltage varistor, the two essential features of microstructure determining its nonlinear response are the formation Bi-enriched active grain boundaries as well as a controlled ZnO grain size by secondary spinel-type phases. Besides, the microstructure and phase composition are strongly affected by the dopant concentration during sintering process. In this study, the optimal dopant levels of Bi2O3, TiO2, and Sb2O3 to achieve maximized nonlinear electrical property (alpha were quantified by the response surface methodology (RSM. RSM was also used to understand the significance and interaction of the factors affecting the response. Variables were determined as the molar ratio of Bi2O3, TiO2, and Sb2O3. The alpha was chosen as response in the study. The 5-level-3-factor central composite design, with 20 runs, was used to conduct the experiments by ball milling method. A quadratic model was established as a functional relationship between three independent variables and alpha. According to the results, the optimum values of Bi2O3, TiO2, and Sb2O3 were obtained 0.52, 0.50, and 0.30, respectively. Under optimal conditions the predicted alpha (9.47 was calculated using optimal coded values from the model and the theoretical value is in good agreement with the value (9.43 obtained by confirmation experiment.

  11. SIMULACIÓN DE MONTE CARLO APLICADA A LA ESTIMACIÓN DE DEPRESIONES RÁPIDAS DE LA TENSIÓN EN REDES ELÉCTRICAS MONTE CARLO SIMULATION APPLIED TO THE ESTIMATION OF VOLTAGE DIPS IN ELECTRIC NETWORKS

    Directory of Open Access Journals (Sweden)

    Miguel Arias Albornoz

    2008-09-01

    Full Text Available En este trabajo se aplica el método de simulación de Monte Carlo (MC para estimar el número de depresiones rápidas de tensión (dips esperados en barras de una red eléctrica. Las estimaciones obtenidas a través de MC se comparan con los resultados de otro método de cálculo conocido como Método de Posiciones de Falla (MPF. Entre los resultados se muestra tanto la convergencia del algoritmo MC a los valores de largo plazo del método MPF como la distribución completa de frecuencias para diferentes eventos, lo cual representa información valiosa para apoyar la toma de decisiones sobre el empleo de equipos sensibles a este tipo de perturbación.In this work, the Monte Carlo simulation method (MC is applied to estimate the number of expected voltage dips in the nodes of an electric network. The estimations obtained through MC are compared with the results of another method of calculation, known as Failure Position Method (MPF. In the results, both the convergence of the algorithm with the long-term values of the MPF method and the complete distribution of frequencies for different events are shown. This represents valuable information to support the decision-making process for equipment that is sensitive to this type of perturbation.

  12. APPLICATION OF HIGH VOLTAGE DIVIDERS FOR POWER QUALITY INDICES MEASUREMENT

    Directory of Open Access Journals (Sweden)

    Y. L. Anokhin

    2017-12-01

    Full Text Available Introduction. Determination of power quality indices in high-voltage power grids allows to find the reasons for the deterioration of the power quality. The relevant national and International Standards for power quality contain relevant norms of quality indices and requirements for their accuracy measurement. Problem. The most complicated part in the process of measuring the power quality indices at high voltage is the selection of the corresponding high-voltage scale voltage converters. Therefore, comparing the requirements of IEC 61000-4-30 to high voltage scale voltage converters is an important task. Goal. Analysis of the International Standard IEC 61000-4-30 requirements feasibility for measuring the indices of power quality in high-voltage electrical networks using different types of high-voltage scale voltage converters. Methodology. Comparison of the requirements of IEC 61000-4-30 Standard to high-voltage scale voltage converters, when measuring power quality indices, with the characteristics of high voltage electromagnetic transformers used in Ukraine, and with promising developments of high-voltage converters of other types. Results. It is shown in the study that in order to fulfill some of the requirements for class A of IEC 61000-4-30, the characteristics of electromagnetic voltage transformers should be determined in the substation conditions using mobile calibration high-voltage laboratories. To meet all the requirements for Class A IEC 61000-4-30, it is recommended to use broadband high-voltage dividers of resistive-capacitive type. Originality. In study it is shown firstly that all the requirements of the IEC 61000-4-30 Standard for high-voltage scale voltage converters can be performed on the basis of the use of broadband resistive-capacitive damped voltage dividers. Practical value. Expositions of specific types of resistive-capacitive high-voltage dividers are presented, their parameters are confirmed by the results of state

  13. Utility of intracerebral theta burst electrical stimulation to attenuate interhemispheric inhibition and to promote motor recovery after cortical injury in an animal model.

    Science.gov (United States)

    Barry, Melissa D; Boddington, Laura J; Igelström, Kajsa M; Gray, Jason P; Shemmell, Jon; Tseng, Kuei Y; Oorschot, Dorothy E; Reynolds, John N J

    2014-11-01

    Following a cerebral cortex injury such as stroke, excessive inhibition around the core of the injury is thought to reduce the potential for new motor learning. In part, this may be caused by an imbalance of interhemispheric inhibition (IHI); therefore, treatments that relieve the inhibitory drive from the healthy hemisphere to the peri-lesional area may enhance motor recovery. Theta burst stimulation delivered by transcranial magnetic stimulation has been tested as a means of normalizing IHI, but clinical results have been variable. Here we use a new rat model of synaptic IHI to demonstrate that electrical intracranial theta burst stimulation causes long-lasting changes in motor cortex excitability. Further, we show that contralateral intermittent theta burst stimulation (iTBS) blocks IHI via a mechanism involving cannabinoid receptors. Finally, we show that contralesional iTBS applied during recovery from cortical injury in rats improves the recovery of motor function. These findings suggest that theta burst stimulation delivered through implanted electrodes may be a promising avenue to explore for augmenting rehabilitation from brain injury. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. A randomized trial of functional electrical stimulation for walking in incomplete spinal cord injury: effects on body composition.

    Science.gov (United States)

    Giangregorio, Lora; Craven, Catharine; Richards, Kieva; Kapadia, Naaz; Hitzig, Sander L; Masani, Kei; Popovic, Milos R

    2012-09-01

    To evaluate the effects of functional electrical stimulation (FES)-assisted walking on body composition, compared to a non-FES exercise program in individuals with a spinal cord injury (SCI). Parallel-group randomized controlled trial. Individuals with chronic (≥ 18 months) incomplete SCI (level C2 to T12, AIS C or D) were recruited and randomized to FES-assisted walking (intervention), or aerobic and resistance training (control) sessions thrice-weekly for 16 weeks. Whole body and leg lean mass and whole body fat mass, measured with dual-energy X-ray absorptiometry, and lower-limb muscle cross-sectional area (CSA) and fat CSA, measured with peripheral computed tomography were assessed at baseline, 4 months, and 12 months. Intention-to-treat analyses using repeated measures general linear models were used to assess between-group differences. Thirty-four individuals were randomized (17 per group); 27 remained at 12 months. There were no significant main effects of FES-assisted walking on body composition variables in intention-to-treat analyses with group means. There was a significant group-by-time interaction for muscle area from baseline to 12 months (P = 0.04). Intention-to-treat analysis of muscle area change scores between baseline and 12 months revealed a significant difference between groups (mean (SD) muscle area change score 212 (517) mm(s) for FES, -136 (268) mm(s) for control, P = 0.026). There were 13 side effects or adverse events deemed related to study participation (7 intervention, 5 control); most were resolved with modifications to the protocol. One fainting episode resulted in a hospital visit and study withdrawal. Thrice-weekly FES-assisted walking exercise over 4 months did not result in a change in body composition in individuals with chronic, motor incomplete C2 to T12 SCI (AIS classification C and D). However, longer-term follow-up revealed that it might maintain muscle area.

  15. Targeted therapies using electrical and magnetic neural stimulation for the treatment of chronic pain in spinal cord injury.

    Science.gov (United States)

    Moreno-Duarte, Ingrid; Morse, Leslie R; Alam, Mahtab; Bikson, Marom; Zafonte, Ross; Fregni, Felipe

    2014-01-15

    Chronic neuropathic pain is one of the most common and disabling symptoms in individuals with spinal cord injury (SCI). Over two-thirds of subjects with SCI suffer from chronic pain influencing quality of life, rehabilitation, and recovery. Given the refractoriness of chronic pain to most pharmacological treatments, the majority of individuals with SCI report worsening of this condition over time. Moreover, only 4-6% of patients in this cohort report improvement. Novel treatments targeting mechanisms associated with pain-maladaptive plasticity, such as electromagnetic neural stimulation, may be desirable to improve outcomes. To date, few, small clinical trials have assessed the effects of invasive and noninvasive nervous system stimulation on pain after SCI. We aimed to review initial efficacy, safety and potential predictors of response by assessing the effects of neural stimulation techniques to treat SCI pain. A literature search was performed using the PubMed database including studies using the following targeted stimulation strategies: transcranial Direct Current Stimulation (tDCS), High Definition tDCS (HD-tDCS), repetitive Transcranial Magnetical Stimulation (rTMS), Cranial Electrotherapy Stimulation (CES), Transcutaneous Electrical Nerve Stimulation (TENS), Spinal Cord Stimulation (SCS) and Motor Cortex Stimulation (MCS), published prior to June of 2012. We included studies from 1998 to 2012. Eight clinical trials and one naturalistic observational study (nine studies in total) met the inclusion criteria. Among the clinical trials, three studies assessed the effects of tDCS, two of CES, two of rTMS and one of TENS. The naturalistic study investigated the analgesic effects of SCS. No clinical trials for epidural motor cortex stimulation (MCS) or HD-tDCS were found. Parameters of stimulation and also clinical characteristics varied significantly across studies. Three out of eight studies showed larger effects sizes (0.73, 0.88 and 1.86 respectively) for pain

  16. Electrical burns in sports fishing: a case report.

    Science.gov (United States)

    Valença-Filipe, R; Egipto, P; Horta, R; Braga, J M; Costa, J; Silva, A

    2014-11-01

    Electrical burns are among the most devastating types of burns, with wide-ranging injuries. They can sometimes occur in the context of fishing, usually involving high voltages. The authors present the case of a 59-year-old-man who suffered a sports accident during a fishing competition, with the formation of an electrical arc due to proximity of the fishing rod and high voltage cables. He presented burns affecting 3% of TBSA, third degree deep burns on trunk and left hand; no signs of cardiac injury. He was admitted to our Burn Unit for monitoring, care dressing and surgical treatment; complete wound healing was achieved after 24 days. Due to its relatively small share among burns, published data on electrical injuries and fishing remain scarce, and differ in patient collectives due to infrastructural or environmental differences. The authors are not aware of published specific reports on electrical burns in sports fishing practice, like the case here presented. The authors want to alert for potential medical, social and economic consequences of this type of sports accidents that could be entirely avoidable with some preventive measures. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  17. High-voltage test and measuring techniques

    CERN Document Server

    Hauschild, Wolfgang

    2014-01-01

    It is the intent of this book to combine high-voltage (HV) engineering with HV testing technique and HV measuring technique. Based on long-term experience gained by the authors as lecturer and researcher as well as member in international organizations, such as IEC and CIGRE, the book will reflect the state of the art as well as the future trends in testing and diagnostics of HV equipment to ensure a reliable generation, transmission and distribution of electrical energy. The book is intended not only for experts but also for students in electrical engineering and high-voltage engineering.

  18. Electrical Safety Program: Nonelectrical Crafts at LANL, Live #12175

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-12-22

    Los Alamos National Laboratory (LANL) and the federal government require those working with or near electrical equipment to be trained on electrical hazards and how to avoid them. Although you might not be trained to work on electrical systems, your understanding of electricity, how it can hurt you, and what precautions to take when working near electricity could save you or others from injury or death. This course, Electrical Safety Program: Nonelectrical Crafts at LANL (12175), provides knowledge of basic electrical concepts, such as current, voltage, and resistance, and their relationship to each other. You will learn how to apply these concepts to safe work practices while learning about the dangers of electricity—and associated hazards—that you may encounter on the job. The course also discusses what you can do to prevent electrical accidents and what you should do in the event of an electrical emergency. The LANL Electrical Safety Program is defined by LANL Procedure (P) 101-13. An electrical safety officer (ESO) is well versed in this document and should be consulted regarding electrical questions. Appointed by the responsible line manager (RLM), ESOs can tell you if a piece of equipment or an operation is safe or how to make it safe.

  19. Model for the ready definition and approximate comparison of alternative high voltage transmission systems. Phases II and III. Application to electric systems within the contiguous United States. [800 and 1200 kV; 400, 600, and 800 kV dc

    Energy Technology Data Exchange (ETDEWEB)

    1979-08-01

    Research on power delivery alternatives is reported. The first phase of this work was to develop a model of overhead transmission systems in the range of 362 to 1200 kV ac, and +-400 to +-800 kV dc. Such systems included transmission from generation to load and inter-connection of two large integrated systems, with and without the existence of an underlying lower voltage network in either case. This phase has been completed. The second and third phases involved application of the model to electric systems within selected regions of the US, and the entire US, respectively, dealing with real situations and including projected expansion to year 1987. The potential benefits and costs of using higher than existing transmission voltages were to be evaluated on this basis. Additionally, the most advantageous new voltage was to be determined taking into account direct and indirect benefits and costs. The results of the second and third phases are presented.

  20. INCREASING THE BREAKDOWN VOLTAGE OF BJT'S AS SWITCHING DEVICES

    Directory of Open Access Journals (Sweden)

    Mustafa SÖNMEZ

    1997-03-01

    Full Text Available The electrical parameters of the transistor must be taken into account in the designing of electronic circuit. One parameter, VCBO, is one of the most important parameter for the designer. Using transistor which has the breakdown voltage of 50 V, it is not possible to obtain 80 V pulse output since the output voltage can not exceed the supply voltage. In this work, a new method is presented to obtain output voltage bigger than supply voltage by using more than one transistor.

  1. Gaseous insulators for high voltage electrical equipment

    Science.gov (United States)

    Christophorou, Loucas G.; James, David R.; Pace, Marshall O.; Pai, Robert Y.

    1979-01-01

    Gaseous insulators comprise compounds having high attachment cross sections for electrons having energies in the 0-1.3 electron volt range. Multi-component gaseous insulators comprise compounds and mixtures having overall high electron attachment cross sections in the 0-1.3 electron volt range and moderating gases having high cross sections for inelastic interactions with electrons of energies 1-4 electron volts. Suitable electron attachment components include hexafluorobutyne, perfluorobutene-2, perfluorocyclobutane, perfluorodimethylcyclobutane, perfluorocyclohexene, perfluoromethylcyclohexane, hexafluorobutadiene, perfluoroheptene-1 and hexafluoroazomethane. Suitable moderating gases include N.sub.2, CO, CO.sub.2 and H.sub.2. The gaseous insulating mixture can also contain SF.sub.6, perfluoropropane and perfluorobenzene.

  2. Effect of high-voltage impulse current on the structure and function of rabbit heart

    Directory of Open Access Journals (Sweden)

    Xin-ping XU

    2011-06-01

    Full Text Available Objective To explore the effect of high-voltage impulse current(HVIC on the structure and function of rabbit heart.Methods Sixty healthy male rabbits were involved in present study and divided into 6 groups randomly(n=10.The rabbits were then shocked using a high-voltage pulse generator with current intensity of 0,50,100,150,250 and 500mA(pulse width 100μs,duration 5s respectively.The heart rate and electrocardiogram(ECG of rabbits were detected before and 0,1,3,7,14 and 28 days after the electric shock.Moreover,the myocardial tissue of rabbits was obtained immediately and 28 days after shock to observe the pathological changes.Results Immediately after electric shock of 50 to 500mA,the heart rate of rabbit increased by different degree,and the ECG showed arrhythmia,myocardial ischemia,atrial fibrillation and atrioventricular block,and the changes recovered gradually one day later.The pathological observation showed cell swelling,separation of myofibril and sarcoplasmic condensation of Purkinje fibers immediately after electric shock of 50 to 500mA,and the changes recovered 28 days after shock.The cardiac injuries aggravated with the increasing of current intensity,especially when it exceeded 150mA,and the recovery time prolonged.Conclusion High-voltage impulse current may induce recoverable injuries on heart structure and function,and the damage effect shows a correlation with the current intensity.

  3. Shaping the spectra of the line-to-line voltage using signal injection in the common mode voltage

    DEFF Research Database (Denmark)

    Mathe, Laszlo; Rasmussen, Peter Omand; Pedersen, John Kim

    2009-01-01

    A drawback of Pulse Width Modulation in electrical drives is the high harmonic content of the line to line voltages, which gives rise to Electro-Magnetic Interference and acoustic noise. By injection of a signal into the common mode voltage, the fundamental is not affected, but new frequency...... components are introduced in the line to line voltage spectrum. This paper introduces a new analytical method for estimation of the line to line voltage spectrum, where sinusoidal signal is injected into the common mode voltage. Based on the analytical calculations, also a new fixed carrier frequency quasi...

  4. Electric field analysis

    CERN Document Server

    Chakravorti, Sivaji

    2015-01-01

    This book prepares newcomers to dive into the realm of electric field analysis. The book details why one should perform electric field analysis and what are its practical implications. It emphasizes both the fundamentals and modern computational methods of electric machines. The book covers practical applications of the numerical methods in high voltage equipment, including transmission lines, power transformers, cables, and gas insulated systems.

  5. The effect of rehabilitation exercises combined with direct vagina low voltage low frequency electric stimulation on pelvic nerve electrophysiology and tissue function in primiparous women: A randomised controlled trial.

    Science.gov (United States)

    Yang, Sumian; Sang, Wenshu; Feng, Jing; Zhao, Haifeng; Li, Xian; Li, Ping; Fan, Hongfang; Tang, Zengjun; Gao, Lina

    2017-03-02

    To evaluate the effect of rehabilitation exercises combined with Direct Vagina Low Voltage Low Frequency Electric Stimulation (DES) on pelvic nerve electrophysiology and tissue function after delivery. Whether and how DES effects pelvic floor dysfunction (PFD) are not known clearly. This was a randomised, controlled clinical trial. The 189 primiparous women 20-35 years old and with an episiotomy or second degree episiotomy tear were divided into three groups: the control group (n = 60) received routine postpartum guidance 2 hr postpartum, the training group (n = 63) performed rehabilitation exercises (Kegel exercises and pelvic movements) from 2 days postpartum until 3 months postpartum, and the combination group (n = 66) received DES 15 times (3 times a week for 30 min at a time) beginning at the sixth week postpartum in addition to performing rehabilitation exercises. Adopt international standard scale and score method to inspect maternal life treatment, such as pelvic organ prolapse situation (POP-Q division), the degree of incontinence score and pelvic floor muscle intensity of muscular contraction. Data were collected during the third month after delivery. Three months postpartum, there were differences among the three groups in the POP-Q grade, the degree of incontinence score, the Oxford grade for pelvic floor muscle strength and the pelvic floor muscle electrophysiology condition. Additionally, there were significant differences regarding the pubic symphysis clearance. Rehabilitation exercises can promote healing of the maternal pubic symphysis and recovery of the pelvis. The total electrical value, type I muscle fibre strength and type II muscle fibre strength were significantly increased in the combination group after treatment than before treatment. Rehabilitation exercises combined with DES were beneficial to the recovery of postpartum pelvic nerve tissue function, and a synergistic effect was observed when the two methods were combined

  6. Modern concepts of treatment and prevention of lightning injuries.

    Science.gov (United States)

    Edlich, Richard F; Farinholt, Heidi-Marie A; Winters, Kathryne L; Britt, L D; Long, William B

    2005-01-01

    Lightning is the second most common cause of weather-related death in the United States. Lightning is a natural atmospheric discharge that occurs between regions of net positive and net negative electric charges. There are several types of lightning, including streak lightning, sheet lightning, ribbon lightning, bead lightning, and ball lightning. Lightning causes injury through five basic mechanisms: direct strike, flash discharge (splash), contact, ground current (step voltage), and blunt trauma. While persons struck by lightning show evidence of multisystem derangement, the most dramatic effects involve the cardiovascular and central nervous systems. Cardiopulmonary arrest is the most common cause of death in lightning victims. Immediate resuscitation of people struck by lightning greatly affects the prognosis. Electrocardiographic changes observed following lightning accidents are probably from primary electric injury or burns of the myocardium without coronary artery occlusion. Lightning induces vasomotor spasm from direct sympathetic stimulation resulting in severe loss of pulses in the extremities. This vasoconstriction may be associated with transient paralysis. Damage to the central nervous system accounts for the second most debilitating group of injuries. Central nervous system injuries from lightning include amnesia and confusion, immediate loss of consciousness, weakness, intracranial injuries, and even brief aphasia. Other organ systems injured by lightning include the eye, ear, gastrointestinal system, skin, and musculoskeletal system. The best treatment of lightning injuries is prevention. The Lightning Safety Guidelines devised by the Lightning Safety Group should be instituted in the United States and other nations to prevent these devastating injuries.

  7. Induced Voltage in an Open Wire

    Science.gov (United States)

    Morawetz, K.; Gilbert, M.; Trupp, A.

    2017-07-01

    A puzzle arising from Faraday's law has been considered and solved concerning the question which voltage will be induced in an open wire with a time-varying homogeneous magnetic field. In contrast to closed wires where the voltage is determined by the time variance of the magnetic field and the enclosed area, in an open wire we have to integrate the electric field along the wire. It is found that the longitudinal electric field with respect to the wave vector contributes with 1/3 and the transverse field with 2/3 to the induced voltage. In order to find the electric fields the sources of the magnetic fields are necessary to know. The representation of a spatially homogeneous and time-varying magnetic field implies unavoidably a certain symmetry point or symmetry line which depend on the geometry of the source. As a consequence the induced voltage of an open wire is found to be the area covered with respect to this symmetry line or point perpendicular to the magnetic field. This in turn allows to find the symmetry points of a magnetic field source by measuring the voltage of an open wire placed with different angles in the magnetic field. We present exactly solvable models of the Maxwell equations for a symmetry point and for a symmetry line, respectively. The results are applicable to open circuit problems like corrosion and for astrophysical applications.

  8. Voltage Control of Spin Waves in Nanostructures

    OpenAIRE

    Chen, Yu-Jin

    2017-01-01

    This dissertation describes the experiments that investigate new methods to control spin waves by electric field. In one experiment, we excite parametric resonance of magnetization in nanoscale magnetic tunnel junctions, which are multilayer thin film devices patterned into nanopillar shape. One of the layers possesses strong perpendicular magnetic anisotropy and exhibits strong voltage-controlled magnetic anisotropy. This magneto-electric effect allows one to modulate the perpendicular magne...

  9. Electric circuits and signals

    CERN Document Server

    Sabah, Nassir H

    2007-01-01

    Circuit Variables and Elements Overview Learning Objectives Electric Current Voltage Electric Power and Energy Assigned Positive Directions Active and Passive Circuit Elements Voltage and Current Sources The Resistor The Capacitor The Inductor Concluding Remarks Summary of Main Concepts and Results Learning Outcomes Supplementary Topics on CD Problems and Exercises Basic Circuit Connections and Laws Overview Learning Objectives Circuit Terminology Kirchhoff's Laws Voltage Division and Series Connection of Resistors Current Division and Parallel Connection of Resistors D-Y Transformation Source Equivalence and Transformation Reduced-Voltage Supply Summary of Main Concepts and Results Learning Outcomes Supplementary Topics and Examples on CD Problems and Exercises Basic Analysis of Resistive Circuits Overview Learning Objectives Number of Independent Circuit Equations Node-Voltage Analysis Special Considerations in Node-Voltage Analysis Mesh-Current Analysis Special Conside...

  10. Remote electrical arc suppression by laser filamentation

    CERN Document Server

    Schubert, Elise; Kasparian, Jérôme; Wolf, Jean-Pierre

    2015-01-01

    We investigate the interaction of narrow plasma channels formed in the filamentation of ultrashort laser pulses, with a DC high voltage. The laser filaments prevent electrical arcs by triggering corona that neutralize the high-voltage electrodes. This phenomenon, due to the electric field modulation and free electron release around the filament, opens new prospects to lightning and over-voltage mitigation.

  11. Electrical system architecture

    Science.gov (United States)

    Algrain, Marcelo C [Peoria, IL; Johnson, Kris W [Washington, IL; Akasam, Sivaprasad [Peoria, IL; Hoff, Brian D [East Peoria, IL

    2008-07-15

    An electrical system for a vehicle includes a first power source generating a first voltage level, the first power source being in electrical communication with a first bus. A second power source generates a second voltage level greater than the first voltage level, the second power source being in electrical communication with a second bus. A starter generator may be configured to provide power to at least one of the first bus and the second bus, and at least one additional power source may be configured to provide power to at least one of the first bus and the second bus. The electrical system also includes at least one power consumer in electrical communication with the first bus and at least one power consumer in electrical communication with the second bus.

  12. [Orthogonal design method to optimize rehabilitation prescription of pulsed electric field at Jiaji (EX-B 2) points for spinal cord injury].

    Science.gov (United States)

    Zhang, Lifeng; Zhang, Hui; Wang, Lin; Liu, Yanyan; Sun, Xianyue; Li, Lingyan; Hou, Jing

    2015-01-01

    By using orthogonal design method to optimnize prescription of pulsed electric field at Jiaji (EX- B 2) points for spinal cord injury (SCI). Fifty six patients of SCI were selected, in which 36 cases were divided into orthogonal design trial and 20 cases were into clinical verification. With 36 patients who received orthogonal design trial, Frankel grading scale was used as observation index to screen optimal prescription of pulsed electric field. Pulse frequency (factor A) included low frequency (factor A(I), 10(2) Hz). moderate frequency (factor A(II), 10(4) Hz) and high frequency (factor A(III), 10(3) Hz); pulse amplitude (factor B) included 0-30 V (factor B ), 0-60 V (factor B(II)) and 0-90 V (factor B(III)); pulse width (factor C) included 0.1 ms (factor C(I)). 0.6 ms (factor C(II)) and 0.9 ms (factor C(III)); acupuncture time (factor D) included one month (DI), three months (D(II)) and five months (D(III)). Twenty patients were used for clinical efficacy observation and the effects of screened optimal pre scription of pulsed electric field at Jiaji (EX-B 2) points combined with regular rehabilitation training on spasm se- verity, score of sensory and motor functions, Barthel index and Frankel score were observed. (1) As results of orthogonal design trial, the optimal prescription was A(III) B(III), C(I), D(III), which were high frequency (10(3) Hz), 0-90 V of pulse amplitude, 0.4 ms of pulse width and 5 months of treatment time. (2) As results of 20 patient clinical verification, Ashworth score, tendon reflex and clonus were all significantly improved (Ppulsed electric field at Jiaji (EX-B 2) points for spinal cord injury is high frequency (10& Hz), 0-90 V of pulse amplitude, 0.4 ms of pulse width and 5 months of treatment time. The optimal prescription of pulsed electric field at Jiaji (EX-B 2) points combined with regular rehabilitation could obviously improve spasm severity, enhance senso- ry and motor functions, and ameliorate activity of daily life and

  13. Low voltage electron beam accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Ochi, Masafumi [Iwasaki Electric Co., Ltd., Tokyo (Japan)

    2003-02-01

    Widely used electron accelerators in industries are the electron beams with acceleration voltage at 300 kV or less. The typical examples are shown on manufactures in Japan, equipment configuration, operation, determination of process parameters, and basic maintenance requirement of the electron beam processors. New electron beam processors with acceleration voltage around 100 kV were introduced maintaining the relatively high dose speed capability of around 10,000 kGy x mpm at production by ESI (Energy Science Inc. USA, Iwasaki Electric Group). The application field like printing and coating for packaging requires treating thickness of 30 micron or less. It does not require high voltage over 110 kV. Also recently developed is a miniature bulb type electron beam tube with energy less than 60 kV. The new application area for this new electron beam tube is being searched. The drive force of this technology to spread in the industries would be further development of new application, process and market as well as the price reduction of the equipment, upon which further acknowledgement and acceptance of the technology to societies and industries would entirely depend. (Y. Tanaka)

  14. Bidirectional current-voltage converters based on magnetostrictive/piezoelectric composites

    NARCIS (Netherlands)

    Jia, Y.; Or, S.W.; Chan, H.L.W.; Jiao, J.; Luo, H.; Van der Zwaag, S.

    2009-01-01

    We report a power supply-free, bidirectional electric current-voltage converter based on a coil-wound laminated composite of magnetostrictive alloy and piezoelectric crystal. An electric current applied to the coil induces a magnetic field, resulting in an electric voltage from the composite due to

  15. Functional electrical stimulation post-spinal cord injury improves locomotion and increases afferent input into the central nervous system in rats.

    Science.gov (United States)

    Beaumont, Eric; Guevara, Edgar; Dubeau, Simon; Lesage, Frederic; Nagai, Mary; Popovic, Milos

    2014-01-01

    Functional electrical stimulation (FES) has been found to be effective in restoring voluntary functions after spinal cord injury (SCI) and stroke. However, the central nervous system (CNS) changes that occur in as a result of this therapy are largely unknown. To examine the effects of FES on the restoration of voluntary locomotor function of the CNS in a SCI rat model. SCI rats were instrumented with chronic FES electrodes in the hindlimb muscles and were divided into two groups: (a) FES therapy and (b) sedentary. At day 7 post-SCI, the animals were assessed for locomotion performance by using a Basso, Beattie and Bresnahan (BBB) scale. They were then anesthetized for a terminal in vivo experiment. The lumbar spinal cord and somatosensory cortex were exposed and the instrumented muscles were stimulated electrically. Associated neurovascular responses in the CNS were recorded with an intrinsic optical imaging system. FES greatly improved locomotion recovery by day 7 post-SCI, as measured by BBB scores (P spinal cord and somatosensory cortex when the muscles were stimulated between 1 and 3 motor threshold (MT). Hind limb rehabilitation with FES is an effective strategy to improve locomotion during the acute phase post-SCI. The results of this study indicate that after FES, the CNS preserves/acquires the capacity to respond to peripheral electrical stimulation.

  16. Simple and compact capacitive voltage probe for measuring voltage impulses up to 0.5 MV.

    Science.gov (United States)

    Pecquois, R; Pecastaing, L; de Ferron, A; Rivaletto, M; Pignolet, P; Novac, B M; Smith, I R; Adler, R J

    2012-03-01

    The paper describes a simple and compact 0.5 MV high-voltage capacitive probe developed in common by Université de Pau (France) and Loughborough University (UK). Design details are provided, together with a simple and straightforward methodology developed to assess the characteristics of high-voltage probes. The technique uses a 4 kV pulsed arrangement combined with results from a 2D electric field solver and a thorough PSpice circuit analysis. Finally, a practical example of high-voltage measurement performed using such a probe during the development phase of a high power microwave generator is provided.

  17. Therapeutic effect of low-frequency pulsed electrical stimulation on melanoma in mice and its injurious effect on myocardium

    Directory of Open Access Journals (Sweden)

    Sha WU

    2015-01-01

    Full Text Available Objective To assess the inhibitory effects of pulsed electrical stimulation at different low frequencies on B16-F10 melanoma, and evaluate its influence on the structure and function of heart in mice. Methods BALB/C mice were inoculation with melanoma cell B16F10 to reproduce melanoma. These mice were randomly divided into four groups: rats in three treatment groups received of pulsed electrical stimulation of 10, 20Hz and 25Hz respectively, with a 1-ms pulse width, field strength of 20 V/cm, and duration of 30 min/d, and no electrical stimulation was given to the control group (10 each. ECG change in each group was recorded. Seven days later, tumor volume and survival rate were recorded. The changes in tumor and myocardial morphology were examined using HE staining. The expression of S-100B protein in tumor was assessed by immunohistochemical method. The serum levels of troponin T (cTnT and creatine kinase isoenzyme (CK-MB were determined by ELISA. Results After being treated with pulsed electrical stimulation for 15 days, tumor volume in 10, 20Hz and 25Hz group (463.0±33.0, 248.6±34.6, 29.9±15.9mm3, respectively, was significantly smaller than that in control group (2027.0±133.4mm3, P0.05. Conclusions Low-frequency pulsed electrical stimulation has a suppressive effect on the growth of B16F10 melanoma in mice, and the pulsed electric stimulation at 20 V/cm, 20 Hz and 1 ms are proved to be the most effective in suppressing the growth of tumor without affecting the normal electrical activity in mice or causing myocardial damage. DOI: 10.11855/j.issn.0577-7402.2014.12.05

  18. Effects of unsymmetrical voltage sags on industrial adjustable speed drives

    Directory of Open Access Journals (Sweden)

    Petronijević Milutin P.

    2009-01-01

    Full Text Available This paper researches unsymmetrical voltage sag influence on torque ripple in scalar controlled (V/Hz, rotor field oriented (RFO and direct torque controlled (DTC drives. Electric drives performance degradation during voltage sag mainly depends on the used control algorithm. Industrial drives with all three types control methods are experimentally tested. Experiments with digital observer's application confirm the proposed solution. .

  19. Comparison CCEM-K8 of DC voltage ratio: results

    CSIR Research Space (South Africa)

    Marullo-Reedtz, G

    2003-04-01

    Full Text Available , he has been with VNIIM where he has been involved in inves- tigation and development of electrical standards of dc voltage and dc current, using quantum effects in LT- and HT-superconductors and ratio voltage mea- surement up to 1000 V. Ronald...

  20. Design and Control of a Dynamic Voltage Restorer

    DEFF Research Database (Denmark)

    Nielsen, John Godsk

    of the described events can be a potential problem for sensitiv loads. During the thesis knowledge is gathered about power quality and power electronics for voltage quality impro